初始化

ReadMe.MD

@@ -0,0 +1,35 @@
+# 说明
+本工程主要是迁移[https://github.com/majbthrd/stm32ecm](https://github.com/majbthrd/stm32ecm)到STM32CubeIDE。
+
+## 迁移说明
+
+* 利用STM32CubeIDE生成工程文件时，需要启用USB并且Device FS应当选择CDC ACM。代码生成后，设置好src文件夹中的源代码，然后取消对工程文件的USB_DEVICE和Middlewares\ST\STM32_USB_Device_Library的编译（也可以直接删除其子文件夹）。
+
+* 根据src/src/ecm_main.h的内容将ecm_main.h中的初始化函数和处理函数放在main.c的合适位置。
+
+
+# 测试结果
+
+* 单片机: STM32F072C8T6
+
+## 测试的OS
+
+* Linux（lubuntu 19.04）
+
+## 测试结果
+
+* 网卡的枚举和识别正常
+
+![](doc/ecm_eth.png)
+
+* DHCP测试不正常，因此需要手动设置IP为192.168.7.2。
+
+* Ping 192.168.7.1正常（已启用lwip对ICMP协议的支持）
+
+![](doc/ecm_ping.png)
+
+* DNS测试正常。能正常解析run.stm和www.run.stm为192.168.7.1。
+
+![](doc/ecm_dns.png)
+
+* HTTP由于存储空间不足无法编译测试。

src/ReadMe.md

@@ -0,0 +1,58 @@
+# 源代码说明
+将此源代码添加到其它工程时，需要进行的工程设置。
+## 头文件目录(相对于当前目录)
+* src/
+* lwip-1.4.1/src/include
+* lwip-1.4.1/src/include/ipv4
+* dhcp-server
+* dns-server
+* lwip-1.4.1/apps/httpserver_raw(由于存储空间不足未启用)
+
+## 源代码文件（相对于当前目录）
+
+* src/ecm_main.c
+* src/time.c
+* src/usb_device.c
+* src/usbd_conf.c
+* src/usbd_core.c
+* src/usbd_ctlreq.c
+* src/usbd_desc.c
+* src/usbd_ecm.c
+* src/usbd_ioreq.c
+
+
+* lwip-1.4.1/src/core/def.c
+* lwip-1.4.1/src/core/dhcp.c
+* lwip-1.4.1/src/core/dns.c
+* lwip-1.4.1/src/core/init.c
+* lwip-1.4.1/src/core/mem.c
+* lwip-1.4.1/src/core/memp.c
+* lwip-1.4.1/src/core/netif.c
+* lwip-1.4.1/src/core/pbuf.c
+* lwip-1.4.1/src/core/raw.c
+* lwip-1.4.1/src/core/stats.c
+* lwip-1.4.1/src/core/sys.c
+* lwip-1.4.1/src/core/tcp.c
+* lwip-1.4.1/src/core/tcp_in.c
+* lwip-1.4.1/src/core/tcp_out.c
+* lwip-1.4.1/src/core/timers.c
+* lwip-1.4.1/src/core/udp.c
+* lwip-1.4.1/src/core/ipv4/autoip.c
+* lwip-1.4.1/src/core/ipv4/icmp.c
+* lwip-1.4.1/src/core/ipv4/igmp.c
+* lwip-1.4.1/src/core/ipv4/inet.c
+* lwip-1.4.1/src/core/ipv4/inet_chksum.c
+* lwip-1.4.1/src/core/ipv4/ip.c
+* lwip-1.4.1/src/core/ipv4/ip_addr.c
+* lwip-1.4.1/src/core/ipv4/ip_frag.c
+* lwip-1.4.1/src/netif/etharp.c
+* lwip-1.4.1/src/netif/ethernetif.c
+* lwip-1.4.1/src/netif/slipif.c
+
+*  dhcp-server/dhserver.c
+
+*  dns-server/dnserver.c
+
+*  lwip-1.4.1/apps/httpserver_raw/fs.c(由于存储空间不足未启用)
+*  lwip-1.4.1/apps/httpserver_raw/httpd.c(由于存储空间不足未启用)
+*  lwip-1.4.1/apps/httpserver_raw/fsdata.c(由于存储空间不足未启用)

src/dhcp-server/dhserver.c

@@ -0,0 +1,344 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 by Sergey Fetisov <fsenok@gmail.com>
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "dhserver.h"
+
+/* DHCP message type */
+#define DHCP_DISCOVER       1
+#define DHCP_OFFER          2
+#define DHCP_REQUEST        3
+#define DHCP_DECLINE        4
+#define DHCP_ACK            5
+#define DHCP_NAK            6
+#define DHCP_RELEASE        7
+#define DHCP_INFORM         8
+
+/* DHCP options */
+enum DHCP_OPTIONS
+{
+	DHCP_PAD                    = 0,
+	DHCP_SUBNETMASK             = 1,
+	DHCP_ROUTER                 = 3,
+	DHCP_DNSSERVER              = 6,
+	DHCP_HOSTNAME               = 12,
+	DHCP_DNSDOMAIN              = 15,
+	DHCP_MTU                    = 26,
+	DHCP_BROADCAST              = 28,
+	DHCP_PERFORMROUTERDISC      = 31,
+	DHCP_STATICROUTE            = 33,
+	DHCP_NISDOMAIN              = 40,
+	DHCP_NISSERVER              = 41,
+	DHCP_NTPSERVER              = 42,
+	DHCP_VENDOR                 = 43,
+	DHCP_IPADDRESS              = 50,
+	DHCP_LEASETIME              = 51,
+	DHCP_OPTIONSOVERLOADED      = 52,
+	DHCP_MESSAGETYPE            = 53,
+	DHCP_SERVERID               = 54,
+	DHCP_PARAMETERREQUESTLIST   = 55,
+	DHCP_MESSAGE                = 56,
+	DHCP_MAXMESSAGESIZE         = 57,
+	DHCP_RENEWALTIME            = 58,
+	DHCP_REBINDTIME             = 59,
+	DHCP_CLASSID                = 60,
+	DHCP_CLIENTID               = 61,
+	DHCP_USERCLASS              = 77,  /* RFC 3004 */
+	DHCP_FQDN                   = 81,
+	DHCP_DNSSEARCH              = 119, /* RFC 3397 */
+	DHCP_CSR                    = 121, /* RFC 3442 */
+	DHCP_MSCSR                  = 249, /* MS code for RFC 3442 */
+	DHCP_END                    = 255
+};
+
+typedef struct
+{
+    uint8_t  dp_op;           /* packet opcode type */
+    uint8_t  dp_htype;        /* hardware addr type */
+    uint8_t  dp_hlen;         /* hardware addr length */
+    uint8_t  dp_hops;         /* gateway hops */
+    uint32_t dp_xid;          /* transaction ID */
+    uint16_t dp_secs;         /* seconds since boot began */
+    uint16_t dp_flags;
+    uint8_t  dp_ciaddr[4];    /* client IP address */
+    uint8_t  dp_yiaddr[4];    /* 'your' IP address */
+    uint8_t  dp_siaddr[4];    /* server IP address */
+    uint8_t  dp_giaddr[4];    /* gateway IP address */
+    uint8_t  dp_chaddr[16];   /* client hardware address */
+    uint8_t  dp_legacy[192];
+    uint8_t  dp_magic[4];     
+    uint8_t  dp_options[275]; /* options area */
+} DHCP_TYPE;
+
+DHCP_TYPE dhcp_data;
+static struct udp_pcb *pcb = NULL;
+static dhcp_config_t *config = NULL;
+
+char magic_cookie[] = {0x63,0x82,0x53,0x63};
+
+static uint32_t get_ip(const uint8_t *pnt)
+{
+  uint32_t result;
+  memcpy(&result, pnt, sizeof(result));
+  return result;
+}
+
+static void set_ip(uint8_t *pnt, uint32_t value)
+{
+  memcpy(pnt, &value, sizeof(value));
+}
+
+static dhcp_entry_t *entry_by_ip(uint32_t ip)
+{
+	int i;
+	for (i = 0; i < config->num_entry; i++)
+		if (get_ip(config->entries[i].addr) == ip)
+			return &config->entries[i];
+	return NULL;
+}
+
+static dhcp_entry_t *entry_by_mac(uint8_t *mac)
+{
+	int i;
+	for (i = 0; i < config->num_entry; i++)
+		if (memcmp(config->entries[i].mac, mac, 6) == 0)
+			return &config->entries[i];
+	return NULL;
+}
+
+static __inline bool is_vacant(dhcp_entry_t *entry)
+{
+	return memcmp("\0\0\0\0\0", entry->mac, 6) == 0;
+}
+
+static dhcp_entry_t *vacant_address()
+{
+	int i;
+	for (i = 0; i < config->num_entry; i++)
+		if (is_vacant(config->entries + i))
+			return config->entries + i;
+	return NULL;
+}
+
+static __inline void free_entry(dhcp_entry_t *entry)
+{
+	memset(entry->mac, 0, 6);
+}
+
+uint8_t *find_dhcp_option(uint8_t *attrs, int size, uint8_t attr)
+{
+	int i = 0;
+	while ((i + 1) < size)
+	{
+		int next = i + attrs[i + 1] + 2;
+		if (next > size) return NULL;
+		if (attrs[i] == attr)
+			return attrs + i;
+		i = next;
+	}
+	return NULL;
+}
+
+int fill_options(void *dest,
+	uint8_t msg_type,
+	const char *domain,
+	uint32_t dns,
+	int lease_time,
+	uint32_t serverid,
+	uint32_t router,
+	uint32_t subnet)
+{
+	uint8_t *ptr = (uint8_t *)dest;
+	/* ACK message type */
+	*ptr++ = 53;
+	*ptr++ = 1;
+	*ptr++ = msg_type;
+
+	/* dhcp server identifier */
+	*ptr++ = DHCP_SERVERID;
+	*ptr++ = 4;
+	set_ip(ptr, serverid);
+	ptr += 4;
+
+	/* lease time */
+	*ptr++ = DHCP_LEASETIME;
+	*ptr++ = 4;
+	*ptr++ = (lease_time >> 24) & 0xFF;
+	*ptr++ = (lease_time >> 16) & 0xFF;
+	*ptr++ = (lease_time >> 8) & 0xFF;
+	*ptr++ = (lease_time >> 0) & 0xFF;
+
+	/* subnet mask */
+	*ptr++ = DHCP_SUBNETMASK;
+	*ptr++ = 4;
+	set_ip(ptr, subnet);
+	ptr += 4;
+
+	/* router */
+	if (router != 0)
+	{
+		*ptr++ = DHCP_ROUTER;
+		*ptr++ = 4;
+		set_ip(ptr, router);
+		ptr += 4;
+	}
+
+	/* domain name */
+	if (domain != NULL)
+	{
+		int len = strlen(domain);
+		*ptr++ = DHCP_DNSDOMAIN;
+		*ptr++ = len;
+		memcpy(ptr, domain, len);
+		ptr += len;
+	}
+
+	/* domain name server (DNS) */
+	if (dns != 0)
+	{
+		*ptr++ = DHCP_DNSSERVER;
+		*ptr++ = 4;
+		set_ip(ptr, dns);
+		ptr += 4;
+	}
+
+	/* end */
+	*ptr++ = DHCP_END;
+	return ptr - (uint8_t *)dest;
+}
+
+static void udp_recv_proc(void *arg, struct udp_pcb *upcb, struct pbuf *p, struct ip_addr *addr, u16_t port)
+{
+	uint8_t *ptr;
+	dhcp_entry_t *entry;
+	struct pbuf *pp;
+
+	int n = p->len;
+	if (n > sizeof(dhcp_data)) n = sizeof(dhcp_data);
+	memcpy(&dhcp_data, p->payload, n);
+	switch (dhcp_data.dp_options[2])
+	{
+		case DHCP_DISCOVER:
+			entry = entry_by_mac(dhcp_data.dp_chaddr);
+			if (entry == NULL) entry = vacant_address();
+			if (entry == NULL) break;
+
+			dhcp_data.dp_op = 2; /* reply */
+			dhcp_data.dp_secs = 0;
+			dhcp_data.dp_flags = 0;
+			set_ip(dhcp_data.dp_yiaddr, get_ip(entry->addr));
+			memcpy(dhcp_data.dp_magic, magic_cookie, 4);
+
+			memset(dhcp_data.dp_options, 0, sizeof(dhcp_data.dp_options));
+
+			fill_options(dhcp_data.dp_options,
+				DHCP_OFFER,
+				config->domain,
+				get_ip(config->dns),
+				entry->lease, 
+				get_ip(config->addr),
+				get_ip(config->addr), 
+				get_ip(entry->subnet));
+
+			pp = pbuf_alloc(PBUF_TRANSPORT, sizeof(dhcp_data), PBUF_POOL);
+			if (pp == NULL) break;
+			memcpy(pp->payload, &dhcp_data, sizeof(dhcp_data));
+			udp_sendto(upcb, pp, IP_ADDR_BROADCAST, port);
+			pbuf_free(pp);
+			break;
+
+		case DHCP_REQUEST:
+			/* 1. find requested ipaddr in option list */
+			ptr = find_dhcp_option(dhcp_data.dp_options, sizeof(dhcp_data.dp_options), DHCP_IPADDRESS);
+			if (ptr == NULL) break;
+			if (ptr[1] != 4) break;
+			ptr += 2;
+
+			/* 2. does hw-address registered? */
+			entry = entry_by_mac(dhcp_data.dp_chaddr);
+			if (entry != NULL) free_entry(entry);
+
+			/* 3. find requested ipaddr */
+			entry = entry_by_ip(get_ip(ptr));
+			if (entry == NULL) break;
+			if (!is_vacant(entry)) break;
+
+			/* 4. fill struct fields */
+			memcpy(dhcp_data.dp_yiaddr, ptr, 4);
+			dhcp_data.dp_op = 2; /* reply */
+			dhcp_data.dp_secs = 0;
+			dhcp_data.dp_flags = 0;
+			memcpy(dhcp_data.dp_magic, magic_cookie, 4);
+
+			/* 5. fill options */
+			memset(dhcp_data.dp_options, 0, sizeof(dhcp_data.dp_options));
+
+			fill_options(dhcp_data.dp_options,
+				DHCP_ACK,
+				config->domain,
+				get_ip(config->dns),
+				entry->lease, 
+				get_ip(config->addr),
+				get_ip(config->addr), 
+				get_ip(entry->subnet));
+
+			/* 6. send ACK */
+			pp = pbuf_alloc(PBUF_TRANSPORT, sizeof(dhcp_data), PBUF_POOL);
+			if (pp == NULL) break;
+			memcpy(entry->mac, dhcp_data.dp_chaddr, 6);
+			memcpy(pp->payload, &dhcp_data, sizeof(dhcp_data));
+			udp_sendto(upcb, pp, IP_ADDR_BROADCAST, port);
+			pbuf_free(pp);
+			break;
+
+		default:
+				break;
+	}
+	pbuf_free(p);
+}
+
+err_t dhserv_init(dhcp_config_t *c)
+{
+	err_t err;
+	udp_init();
+	dhserv_free();
+	pcb = udp_new();
+	if (pcb == NULL)
+		return ERR_MEM;
+	err = udp_bind(pcb, IP_ADDR_ANY, c->port);
+	if (err != ERR_OK)
+	{
+		dhserv_free();
+		return err;
+	}
+	udp_recv(pcb, udp_recv_proc, NULL);
+	config = c;
+	return ERR_OK;
+}
+
+void dhserv_free(void)
+{
+	if (pcb == NULL) return;
+	udp_remove(pcb);
+	pcb = NULL;
+}

src/dhcp-server/dhserver.h

@@ -0,0 +1,63 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 by Sergey Fetisov <fsenok@gmail.com>
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+/*
+ * version: 1.0 demo (7.02.2015)
+ * brief:   tiny dhcp ipv4 server using lwip (pcb)
+ * ref:     https://lists.gnu.org/archive/html/lwip-users/2012-12/msg00016.html
+ */
+
+#ifndef DHSERVER_H
+#define DHSERVER_H
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include "lwip/err.h"
+#include "lwip/udp.h"
+#include "netif/etharp.h"
+
+typedef struct dhcp_entry
+{
+	uint8_t  mac[6];
+	uint8_t  addr[4];
+	uint8_t  subnet[4];
+	uint32_t lease;
+} dhcp_entry_t;
+
+typedef struct dhcp_config
+{
+	uint8_t       addr[4];
+	uint16_t      port;
+	uint8_t       dns[4];
+	const char   *domain;
+	int           num_entry;
+	dhcp_entry_t *entries;
+} dhcp_config_t;
+
+err_t dhserv_init(dhcp_config_t *config);
+void dhserv_free(void);
+
+#endif /* DHSERVER_H */

src/dns-server/dnserver.c

@@ -0,0 +1,198 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 by Sergey Fetisov <fsenok@gmail.com>
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+/*
+ * version: 1.0 demo (7.02.2015)
+ * brief:   tiny dns ipv4 server using lwip (pcb)
+ */
+
+#include "dnserver.h"
+
+#define DNS_MAX_HOST_NAME_LEN 128
+
+static struct udp_pcb *pcb = NULL;
+dns_query_proc_t query_proc = NULL;
+
+#pragma pack(push, 1)
+typedef struct
+{
+#if BYTE_ORDER == LITTLE_ENDIAN
+	uint8_t rd: 1,     /* Recursion Desired */
+	        tc: 1,     /* Truncation Flag */
+	        aa: 1,     /* Authoritative Answer Flag */
+	        opcode: 4, /* Operation code */
+	        qr: 1;     /* Query/Response Flag */
+	uint8_t rcode: 4,  /* Response Code */
+	        z: 3,      /* Zero */
+	        ra: 1;     /* Recursion Available */
+#else
+	uint8_t qr: 1,     /* Query/Response Flag */
+	        opcode: 4, /* Operation code */
+	        aa: 1,     /* Authoritative Answer Flag */
+	        tc: 1,     /* Truncation Flag */
+	        rd: 1;     /* Recursion Desired */
+	uint8_t ra: 1,     /* Recursion Available */
+	        z: 3,      /* Zero */
+	        rcode: 4;  /* Response Code */
+#endif
+} dns_header_flags_t;
+
+typedef struct
+{
+	uint16_t id;
+	dns_header_flags_t flags;
+	uint16_t n_record[4];
+} dns_header_t;
+
+typedef struct dns_answer
+{
+	uint16_t name;
+	uint16_t type;
+	uint16_t Class;
+	uint32_t ttl;
+	uint16_t len;
+	uint32_t addr;
+} dns_answer_t;
+#pragma pack(pop)
+
+typedef struct dns_query
+{
+	char name[DNS_MAX_HOST_NAME_LEN];
+	uint16_t type;
+	uint16_t Class;
+} dns_query_t;
+
+static uint16_t get_uint16(const uint8_t *pnt)
+{
+  uint16_t result;
+  memcpy(&result, pnt, sizeof(result));
+  return result;
+}
+
+static int parse_next_query(void *data, int size, dns_query_t *query)
+{
+	int len;
+	int lables;
+	uint8_t *ptr;
+
+	len = 0;
+	lables = 0;
+	ptr = (uint8_t *)data;
+
+	while (true)
+	{
+		uint8_t lable_len;
+		if (size <= 0) return -1;
+		lable_len = *ptr++;
+		size--;
+		if (lable_len == 0) break;
+		if (lables > 0)
+		{
+			if (len == DNS_MAX_HOST_NAME_LEN) return -2;
+			query->name[len++] = '.';
+		}
+		if (lable_len > size) return -1;
+		if (len + lable_len >= DNS_MAX_HOST_NAME_LEN) return -2;
+		memcpy(&query->name[len], ptr, lable_len);
+		len += lable_len;
+		ptr += lable_len;
+		size -= lable_len;
+		lables++;
+	}
+
+	if (size < 4) return -1;
+	query->name[len] = 0;
+	query->type = get_uint16(ptr);
+	ptr += 2;
+	query->Class = get_uint16(ptr);
+	ptr += 2;
+	return ptr - (uint8_t *)data;
+}
+
+static void udp_recv_proc(void *arg, struct udp_pcb *upcb, struct pbuf *p, struct ip_addr *addr, u16_t port)
+{
+	int len;
+	dns_header_t *header;
+	static dns_query_t query;
+	struct pbuf *out;
+	ip_addr_t host_addr;
+	dns_answer_t *answer;
+
+	if (p->len <= sizeof(dns_header_t)) goto error;
+	header = (dns_header_t *)p->payload;
+	if (header->flags.qr != 0) goto error;
+	if (ntohs(header->n_record[0]) != 1) goto error;
+
+	len = parse_next_query(header + 1, p->len - sizeof(dns_header_t), &query);
+	if (len < 0) goto error;
+	if (!query_proc(query.name, &host_addr)) goto error;
+
+	len += sizeof(dns_header_t);
+	out = pbuf_alloc(PBUF_TRANSPORT, len + 16, PBUF_POOL);
+	if (out == NULL) goto error;
+
+	memcpy(out->payload, p->payload, len);
+	header = (dns_header_t *)out->payload;
+	header->flags.qr = 1;
+	header->n_record[1] = htons(1);
+	answer = (struct dns_answer *)((uint8_t *)out->payload + len);
+	answer->name = htons(0xC00C);
+	answer->type = htons(1);
+	answer->Class = htons(1);
+	answer->ttl = htonl(32);
+	answer->len = htons(4);
+	answer->addr = host_addr.addr;
+	
+	udp_sendto(upcb, out, addr, port);
+	pbuf_free(out);
+
+error:
+	pbuf_free(p);
+}
+
+err_t dnserv_init(ip_addr_t *bind, uint16_t port, dns_query_proc_t qp)
+{
+	err_t err;
+	udp_init();
+	dnserv_free();
+	pcb = udp_new();
+	if (pcb == NULL)
+		return ERR_MEM;
+	err = udp_bind(pcb, bind, port);
+	if (err != ERR_OK)
+	{
+		dnserv_free();
+		return err;
+	}
+	udp_recv(pcb, udp_recv_proc, NULL);
+	query_proc = qp;
+	return ERR_OK;
+}
+
+void dnserv_free()
+{
+	if (pcb == NULL) return;
+	udp_remove(pcb);
+	pcb = NULL;
+}

src/dns-server/dnserver.h

@@ -0,0 +1,47 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 by Sergey Fetisov <fsenok@gmail.com>
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+/*
+ * version: 1.0 demo (7.02.2015)
+ * brief:   tiny dns ipv4 server using lwip (pcb)
+ */
+
+#ifndef DNSERVER
+#define DNSERVER
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include "lwip/def.h"
+#include "lwip/err.h"
+#include "lwip/udp.h"
+#include "netif/etharp.h"
+
+typedef bool (*dns_query_proc_t)(const char *name, ip_addr_t *addr);
+
+err_t dnserv_init(ip_addr_t *bind, uint16_t port, dns_query_proc_t query_proc);
+void  dnserv_free(void);
+
+#endif

src/lwip-1.4.1/COPYING

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2001, 2002 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+

src/lwip-1.4.1/FILES

@@ -0,0 +1,4 @@
+src/      - The source code for the lwIP TCP/IP stack.
+doc/      - The documentation for lwIP.
+
+See also the FILES file in each subdirectory.

src/lwip-1.4.1/README

@@ -0,0 +1,89 @@
+INTRODUCTION
+
+lwIP is a small independent implementation of the TCP/IP protocol
+suite that has been developed by Adam Dunkels at the Computer and
+Networks Architectures (CNA) lab at the Swedish Institute of Computer
+Science (SICS).
+
+The focus of the lwIP TCP/IP implementation is to reduce the RAM usage
+while still having a full scale TCP. This making lwIP suitable for use
+in embedded systems with tens of kilobytes of free RAM and room for
+around 40 kilobytes of code ROM.
+
+FEATURES
+
+  * IP (Internet Protocol) including packet forwarding over multiple network
+    interfaces
+  * ICMP (Internet Control Message Protocol) for network maintenance and debugging
+  * IGMP (Internet Group Management Protocol) for multicast traffic management
+  * UDP (User Datagram Protocol) including experimental UDP-lite extensions
+  * TCP (Transmission Control Protocol) with congestion control, RTT estimation
+    and fast recovery/fast retransmit
+  * Specialized raw/native API for enhanced performance
+  * Optional Berkeley-like socket API
+  * DNS (Domain names resolver)
+  * SNMP (Simple Network Management Protocol)
+  * DHCP (Dynamic Host Configuration Protocol)
+  * AUTOIP (for IPv4, conform with RFC 3927)
+  * PPP (Point-to-Point Protocol)
+  * ARP (Address Resolution Protocol) for Ethernet
+
+LICENSE
+
+lwIP is freely available under a BSD license.
+
+DEVELOPMENT
+
+lwIP has grown into an excellent TCP/IP stack for embedded devices,
+and developers using the stack often submit bug fixes, improvements,
+and additions to the stack to further increase its usefulness.
+
+Development of lwIP is hosted on Savannah, a central point for
+software development, maintenance and distribution. Everyone can
+help improve lwIP by use of Savannah's interface, CVS and the
+mailing list. A core team of developers will commit changes to the
+CVS source tree.
+
+The lwIP TCP/IP stack is maintained in the 'lwip' CVS module and
+contributions (such as platform ports) are in the 'contrib' module.
+
+See doc/savannah.txt for details on CVS server access for users and
+developers.
+
+Last night's CVS tar ball can be downloaded from:
+  http://savannah.gnu.org/cvs.backups/lwip.tar.gz [CHANGED - NEEDS FIXING]
+
+The current CVS trees are web-browsable:
+  http://savannah.nongnu.org/cgi-bin/viewcvs/lwip/lwip/
+  http://savannah.nongnu.org/cgi-bin/viewcvs/lwip/contrib/
+
+Submit patches and bugs via the lwIP project page:
+  http://savannah.nongnu.org/projects/lwip/
+
+
+DOCUMENTATION
+
+The original out-dated homepage of lwIP and Adam Dunkels' papers on
+lwIP are at the official lwIP home page:
+  http://www.sics.se/~adam/lwip/
+
+Self documentation of the source code is regularly extracted from the
+current CVS sources and is available from this web page:
+  http://www.nongnu.org/lwip/
+
+There is now a constantly growin wiki about lwIP at
+  http://lwip.wikia.com/wiki/LwIP_Wiki
+
+Also, there are mailing lists you can subscribe at
+  http://savannah.nongnu.org/mail/?group=lwip
+plus searchable archives:
+  http://lists.nongnu.org/archive/html/lwip-users/
+  http://lists.nongnu.org/archive/html/lwip-devel/
+
+Reading Adam's papers, the files in docs/, browsing the source code
+documentation and browsing the mailing list archives is a good way to
+become familiar with the design of lwIP.
+
+Adam Dunkels <adam@sics.se>
+Leon Woestenberg <leon.woestenberg@gmx.net>
+

src/lwip-1.4.1/UPGRADING

@@ -0,0 +1,144 @@
+This file lists major changes between release versions that require
+ports or applications to be changed. Use it to update a port or an
+application written for an older version of lwIP to correctly work
+with newer versions.
+
+
+(CVS HEAD)
+
+  * [Enter new changes just after this line - do not remove this line]
+
+  ++ Application changes:
+
+  * Replaced struct ip_addr by typedef ip_addr_t (struct ip_addr is kept for
+    compatibility to old applications, but will be removed in the future).
+
+  * Renamed mem_realloc() to mem_trim() to prevent confusion with realloc()
+
+  +++ Raw API:
+    * Changed the semantics of tcp_close() (since it was rather a
+      shutdown before): Now the application does *NOT* get any calls to the recv
+      callback (aside from NULL/closed) after calling tcp_close()
+
+    * When calling tcp_abort() from a raw API TCP callback function,
+      make sure you return ERR_ABRT to prevent accessing unallocated memory.
+      (ERR_ABRT now means the applicaiton has called tcp_abort!)
+
+  +++ Netconn API:
+    * Changed netconn_receive() and netconn_accept() to return
+      err_t, not a pointer to new data/netconn.
+
+  +++ Socket API:
+    * LWIP_SO_RCVTIMEO: when accept() or recv() time out, they
+      now set errno to EWOULDBLOCK/EAGAIN, not ETIMEDOUT.
+
+    * Added a minimal version of posix fctl() to have a
+      standardised way to set O_NONBLOCK for nonblocking sockets.
+
+  +++ all APIs:
+    * correctly implemented SO(F)_REUSEADDR
+
+  ++ Port changes
+
+  +++ new files:
+
+    * Added 4 new files: def.c, timers.c, timers.h, tcp_impl.h:
+
+    * Moved stack-internal parts of tcp.h to tcp_impl.h, tcp.h now only contains
+      the actual application programmer's API
+  
+    * Separated timer implementation from sys.h/.c, moved to timers.h/.c;
+      Added timer implementation for NO_SYS==1, set NO_SYS_NO_TIMERS==1 if you
+      still want to use your own timer implementation for NO_SYS==0 (as before).
+
+  +++ sys layer:
+
+    * Converted mbox- and semaphore-functions to take pointers to sys_mbox_t/
+      sys_sem_t;
+
+    * Converted sys_mbox_new/sys_sem_new to take pointers and return err_t;
+
+    * Added Mutex concept in sys_arch (define LWIP_COMPAT_MUTEX to let sys.h use
+      binary semaphores instead of mutexes - as before)
+
+  +++ new options:
+
+     * Don't waste memory when chaining segments, added option TCP_OVERSIZE to
+       prevent creating many small pbufs when calling tcp_write with many small
+       blocks of data. Instead, pbufs are allocated larger than needed and the
+       space is used for later calls to tcp_write.
+
+     * Added LWIP_NETIF_TX_SINGLE_PBUF to always copy to try to create single pbufs
+       in tcp_write/udp_send.
+
+    * Added an additional option LWIP_ETHERNET to support ethernet without ARP
+      (necessary for pure PPPoE)
+
+    * Add MEMP_SEPARATE_POOLS to place memory pools in separate arrays. This may
+      be used to place these pools into user-defined memory by using external
+      declaration.
+
+    * Added TCP_SNDQUEUELOWAT corresponding to TCP_SNDLOWAT
+
+  +++ new pools:
+
+     * Netdb uses a memp pool for allocating memory when getaddrinfo() is called,
+       so MEMP_NUM_NETDB has to be set accordingly.
+
+     * DNS_LOCAL_HOSTLIST_IS_DYNAMIC uses a memp pool instead of the heap, so
+       MEMP_NUM_LOCALHOSTLIST has to be set accordingly.
+
+     * Snmp-agent uses a memp pools instead of the heap, so MEMP_NUM_SNMP_* have
+       to be set accordingly.
+
+     * PPPoE uses a MEMP pool instead of the heap, so MEMP_NUM_PPPOE_INTERFACES
+       has to be set accordingly
+
+  * Integrated loopif into netif.c - loopif does not have to be created by the
+    port any more, just define LWIP_HAVE_LOOPIF to 1.
+
+  * Added define LWIP_RAND() for lwip-wide randomization (needs to be defined
+    in cc.h, e.g. used by igmp)
+
+  * Added printf-formatter X8_F to printf u8_t as hex
+
+  * The heap now may be moved to user-defined memory by defining
+    LWIP_RAM_HEAP_POINTER as a void pointer to that memory's address
+
+  * added autoip_set_struct() and dhcp_set_struct() to let autoip and dhcp work
+    with user-allocated structs instead of calling mem_malloc
+
+  * Added const char* name to mem- and memp-stats for easier debugging.
+
+  * Calculate the TCP/UDP checksum while copying to only fetch data once:
+    Define LWIP_CHKSUM_COPY to a memcpy-like function that returns the checksum
+
+  * Added SO_REUSE_RXTOALL to pass received UDP broadcast/multicast packets to
+    more than one pcb.
+
+  * Changed the semantics of ARP_QUEUEING==0: ARP_QUEUEING now cannot be turned
+    off any more, if this is set to 0, only one packet (the most recent one) is
+    queued (like demanded by RFC 1122).
+
+  
+  ++ Major bugfixes/improvements
+
+  * Implemented tcp_shutdown() to only shut down one end of a connection
+  * Implemented shutdown() at socket- and netconn-level
+  * Added errorset support to select() + improved select speed overhead
+  * Merged pppd to v2.3.11 (including some backported bugfixes from 2.4.x)
+  * Added timer implementation for NO_SYS==1 (may be disabled with NO_SYS_NO_TIMERS==1
+  * Use macros defined in ip_addr.h to work with IP addresses
+  * Implemented many nonblocking socket/netconn functions
+  * Fixed ARP input processing: only add a new entry if a request was directed as us
+  * mem_realloc() to mem_trim() to prevent confusion with realloc()
+  * Some improvements for AutoIP (don't route/forward link-local addresses, don't break
+    existing connections when assigning a routable address)
+  * Correctly handle remote side overrunning our rcv_wnd in ooseq case
+  * Removed packing from ip_addr_t, the packed version is now only used in protocol headers
+  * Corrected PBUF_POOL_BUFSIZE for ports where ETH_PAD_SIZE > 0
+  * Added support for static ARP table entries
+
+(STABLE-1.3.2)
+
+  * initial version of this file

src/lwip-1.4.1/apps/chargen/README

@@ -0,0 +1,52 @@
+
+        CHARGEN
+        
+This file implements a nice example of handling multiple tcp sockets in a
+server environment. Just call chargen_init() from your application after
+you have initialized lwip and added your network interfaces. Change the
+MAX_SERV option to increase or decrease the number of sessions supported.
+
+chargen will jam as much data as possible into the output socket, so it
+will take up a lot of CPU time. Therefore it will be a good idea to run it
+as the lowest possible priority (just ahead of any idle task).
+ 
+This is also a good example of how to support multiple sessions in an
+embedded system where you might not have fork(). The multiple sessions are
+all handled by the same thread and select() is used for demultiplexing.
+ 
+No makefile is provided, just add chargen to the makefile for your
+application. It is OS and HW independent.
+
+Once the chargen server is running in your application, go to another system
+and open a telnet session to your lwip platform at port 19. You should see an
+ASCII pattern start to stream on you screen.
+
+As an example, lets say that your system running lwip is at IP address
+192.168.10.244 and you have a linux system connected to it at IP address
+192.168.10.59. Issue the following command at a terminal prompt on the linux system:
+
+telnet 192.168.10.244 19
+
+You will see a pattern similar to the following on streaming by on your
+screen:
+
+ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{
+BCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|
+CDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}
+DEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~
+EFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!
+FGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"
+GHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"#
+HIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"#$
+IJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"#$%
+JKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"#$%&
+KLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"#$%&'
+LMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~!"#$%&'(
+
+It even works from windows: At a dos prompt you can also issue the same
+telnet command and you will get a similar (but much slower, at least on W98)
+data stream.
+
+David Haas
+
+

src/lwip-1.4.1/apps/chargen/chargen.c

@@ -0,0 +1,269 @@
+/** @file
+ *
+ *  chargen server for lwip
+ */
+/*
+ * Copyright (c) 2003 NBS Card Technology, Paramus, NJ.
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: David Haas <dhaas@alum.rpi.edu>
+ *
+ * Purpose:   chargen server for testing and demonstration purposes
+ *
+ * This file implements a nice example of handling multiple tcp sockets in a
+ * server environment. Just call chargen_init() from your application after
+ * you have initialized lwip and added your network interfaces. Change the
+ * MAX_SERV option to increase or decrease the number of sessions supported.
+ *
+ * chargen will jam as much data as possible into the output socket, so it
+ * will take up a lot of CPU time. Therefore it will be a good idea to run it
+ * as the lowest possible priority (just ahead of any idle task).
+ *
+ * This is also a good example of how to support multiple sessions in an
+ * embedded system where you might not have fork().
+ */
+
+#include "lwip/opt.h"
+#include "lwip/sys.h"
+#include "lwip/sockets.h"
+#include "lwip/mem.h"
+
+#include <string.h>
+
+#include "chargen.h"
+
+#if LWIP_SOCKET
+
+#define MAX_SERV                 5         /* Maximum number of chargen services. Don't need too many */
+#define CHARGEN_THREAD_NAME      "chargen"
+#define CHARGEN_PRIORITY         254       /* Really low priority */
+#define CHARGEN_THREAD_STACKSIZE 0
+#define SEND_SIZE TCP_SNDLOWAT             /* If we only send this much, then when select
+                                              says we can send, we know we won't block */
+struct charcb 
+{
+    struct charcb *next;
+    int socket;
+    struct sockaddr_in cliaddr;
+    socklen_t clilen;
+    char nextchar;
+};
+
+static struct charcb *charcb_list = 0;
+static int do_read(struct charcb *p_charcb);
+static void close_chargen(struct charcb *p_charcb);
+
+/**************************************************************
+ * void chargen_thread(void *arg)
+ *
+ * chargen task. This server will wait for connections on well
+ * known TCP port number: 19. For every connection, the server will
+ * write as much data as possible to the tcp port.
+ **************************************************************/
+static void chargen_thread(void *arg)
+{
+    int listenfd;
+    struct sockaddr_in chargen_saddr;
+    fd_set readset;
+    fd_set writeset;
+    int i, maxfdp1;
+    struct charcb *p_charcb;
+    LWIP_UNUSED_ARG(arg);
+
+    /* First acquire our socket for listening for connections */
+    listenfd = socket(AF_INET, SOCK_STREAM, 0);
+
+    LWIP_ASSERT("chargen_thread(): Socket create failed.", listenfd >= 0);
+    memset(&chargen_saddr, 0, sizeof(chargen_saddr));
+    chargen_saddr.sin_family = AF_INET;
+    chargen_saddr.sin_addr.s_addr = PP_HTONL(INADDR_ANY);
+    chargen_saddr.sin_port = htons(19);     /* Chargen server port */
+
+    if (bind(listenfd, (struct sockaddr *) &chargen_saddr, sizeof(chargen_saddr)) == -1)
+        LWIP_ASSERT("chargen_thread(): Socket bind failed.", 0);
+
+    /* Put socket into listening mode */
+    if (listen(listenfd, MAX_SERV) == -1)
+        LWIP_ASSERT("chargen_thread(): Listen failed.", 0);
+
+    
+    /* Wait forever for network input: This could be connections or data */
+    for (;;)
+    {
+        maxfdp1 = listenfd+1;
+
+        /* Determine what sockets need to be in readset */
+        FD_ZERO(&readset);
+        FD_ZERO(&writeset);
+        FD_SET(listenfd, &readset);
+        for (p_charcb = charcb_list; p_charcb; p_charcb = p_charcb->next)
+        {
+                if (maxfdp1 < p_charcb->socket + 1)
+                    maxfdp1 = p_charcb->socket + 1;
+                FD_SET(p_charcb->socket, &readset);
+                FD_SET(p_charcb->socket, &writeset);
+        }
+
+        /* Wait for data or a new connection */
+        i = select(maxfdp1, &readset, &writeset, 0, 0);
+        
+        if (i == 0)
+            continue;
+        /* At least one descriptor is ready */
+        if (FD_ISSET(listenfd, &readset))
+        {
+            /* We have a new connection request!!! */
+            /* Lets create a new control block */
+            p_charcb = (struct charcb *)mem_malloc(sizeof(struct charcb));
+            if (p_charcb)
+            {
+                p_charcb->socket = accept(listenfd,
+                                        (struct sockaddr *) &p_charcb->cliaddr,
+                                        &p_charcb->clilen);
+                if (p_charcb->socket < 0)
+                    mem_free(p_charcb);
+                else
+                {
+                    /* Keep this tecb in our list */
+                    p_charcb->next = charcb_list;
+                    charcb_list = p_charcb;
+                    p_charcb->nextchar = 0x21;
+                }
+            } else {
+                /* No memory to accept connection. Just accept and then close */
+                int sock;
+                struct sockaddr cliaddr;
+                socklen_t clilen;
+
+                sock = accept(listenfd, &cliaddr, &clilen);
+                if (sock >= 0)
+                    close(sock);
+            }
+        }
+        /* Go through list of connected clients and process data */
+        for (p_charcb = charcb_list; p_charcb; p_charcb = p_charcb->next)
+        {
+            if (FD_ISSET(p_charcb->socket, &readset))
+            {
+                /* This socket is ready for reading. This could be because someone typed
+                 * some characters or it could be because the socket is now closed. Try reading
+                 * some data to see. */
+                if (do_read(p_charcb) < 0)
+                    break;
+            }
+            if (FD_ISSET(p_charcb->socket, &writeset))
+            {
+                char line[80];
+                char setchar = p_charcb->nextchar;
+
+                for( i = 0; i < 59; i++)
+                {
+                    line[i] = setchar;
+                    if (++setchar == 0x7f)
+                        setchar = 0x21;
+                }
+                line[i] = 0;
+                strcat(line, "\n\r");
+                if (write(p_charcb->socket, line, strlen(line)) < 0)
+                {
+                    close_chargen(p_charcb);
+                    break;
+                }
+                if (++p_charcb->nextchar == 0x7f)
+                    p_charcb->nextchar = 0x21;
+            }
+            
+        }
+    }
+    
+    
+}
+
+/**************************************************************
+ * void close_chargen(struct charcb *p_charcb)
+ *
+ * Close the socket and remove this charcb from the list.
+ **************************************************************/
+static void close_chargen(struct charcb *p_charcb)
+{
+    struct charcb *p_search_charcb;
+
+        /* Either an error or tcp connection closed on other
+         * end. Close here */
+        close(p_charcb->socket);
+        /* Free charcb */
+        if (charcb_list == p_charcb)
+            charcb_list = p_charcb->next;
+        else
+            for (p_search_charcb = charcb_list; p_search_charcb; p_search_charcb = p_search_charcb->next)
+            {
+                if (p_search_charcb->next == p_charcb)
+                {
+                    p_search_charcb->next = p_charcb->next;
+                    break;
+                }
+            }
+        mem_free(p_charcb);
+}
+
+
+/**************************************************************
+ * void do_read(struct charcb *p_charcb)
+ *
+ * Socket definitely is ready for reading. Read a buffer from the socket and
+ * discard the data.  If no data is read, then the socket is closed and the
+ * charcb is removed from the list and freed.
+ **************************************************************/
+static int do_read(struct charcb *p_charcb)
+{
+    char buffer[80];
+    int readcount;
+
+    /* Read some data */
+    readcount = read(p_charcb->socket, &buffer, 80);
+    if (readcount <= 0)
+    {
+        close_chargen(p_charcb);
+        return -1;
+    }
+    return 0;
+}
+
+
+/**************************************************************
+ * void chargen_init(void)
+ *
+ * This function initializes the chargen service. This function
+ * may only be called either before or after tasking has started.
+ **************************************************************/
+void chargen_init(void)
+{
+    sys_thread_new( CHARGEN_THREAD_NAME, chargen_thread, 0, CHARGEN_THREAD_STACKSIZE, CHARGEN_PRIORITY);
+    
+}
+
+#endif /* LWIP_SOCKET */

src/lwip-1.4.1/apps/chargen/chargen.h

@@ -0,0 +1,13 @@
+#ifndef __CHARGEN_H__
+#define __CHARGEN_H__
+
+#include "lwip/opt.h"
+
+#if LWIP_SOCKET
+
+void chargen_init(void);
+
+#endif /* LWIP_SOCKET */
+
+
+#endif /* __CHARGEN_H__ */

src/lwip-1.4.1/apps/httpserver/README

@@ -0,0 +1,12 @@
+HTTPSERVER
+
+This is a demonstration of how to make the most basic kind 
+of server using lWIP.
+
+* httpserver-raw.c - uses raw TCP calls (coming soon!)
+
+* httpserver-netconn.c - uses netconn and netbuf API
+
+This code updates the examples in Adam Dunkel's original
+lwIP documentation to match changes in the code since that
+PDF release. 

src/lwip-1.4.1/apps/httpserver/httpserver-netconn.c

@@ -0,0 +1,99 @@
+
+#include "lwip/opt.h"
+#include "lwip/arch.h"
+#include "lwip/api.h"
+
+#include "httpserver-netconn.h"
+
+#if LWIP_NETCONN
+
+#ifndef HTTPD_DEBUG
+#define HTTPD_DEBUG         LWIP_DBG_OFF
+#endif
+
+const static char http_html_hdr[] = "HTTP/1.1 200 OK\r\nContent-type: text/html\r\n\r\n";
+const static char http_index_html[] = "<html><head><title>Congrats!</title></head><body><h1>Welcome to our lwIP HTTP server!</h1><p>This is a small test page, served by httpserver-netconn.</body></html>";
+
+/** Serve one HTTP connection accepted in the http thread */
+static void
+http_server_netconn_serve(struct netconn *conn)
+{
+  struct netbuf *inbuf;
+  char *buf;
+  u16_t buflen;
+  err_t err;
+  
+  /* Read the data from the port, blocking if nothing yet there. 
+   We assume the request (the part we care about) is in one netbuf */
+  err = netconn_recv(conn, &inbuf);
+  
+  if (err == ERR_OK) {
+    netbuf_data(inbuf, (void**)&buf, &buflen);
+    
+    /* Is this an HTTP GET command? (only check the first 5 chars, since
+    there are other formats for GET, and we're keeping it very simple )*/
+    if (buflen>=5 &&
+        buf[0]=='G' &&
+        buf[1]=='E' &&
+        buf[2]=='T' &&
+        buf[3]==' ' &&
+        buf[4]=='/' ) {
+      
+      /* Send the HTML header 
+             * subtract 1 from the size, since we dont send the \0 in the string
+             * NETCONN_NOCOPY: our data is const static, so no need to copy it
+       */
+      netconn_write(conn, http_html_hdr, sizeof(http_html_hdr)-1, NETCONN_NOCOPY);
+      
+      /* Send our HTML page */
+      netconn_write(conn, http_index_html, sizeof(http_index_html)-1, NETCONN_NOCOPY);
+    }
+  }
+  /* Close the connection (server closes in HTTP) */
+  netconn_close(conn);
+  
+  /* Delete the buffer (netconn_recv gives us ownership,
+   so we have to make sure to deallocate the buffer) */
+  netbuf_delete(inbuf);
+}
+
+/** The main function, never returns! */
+static void
+http_server_netconn_thread(void *arg)
+{
+  struct netconn *conn, *newconn;
+  err_t err;
+  LWIP_UNUSED_ARG(arg);
+  
+  /* Create a new TCP connection handle */
+  conn = netconn_new(NETCONN_TCP);
+  LWIP_ERROR("http_server: invalid conn", (conn != NULL), return;);
+  
+  /* Bind to port 80 (HTTP) with default IP address */
+  netconn_bind(conn, NULL, 80);
+  
+  /* Put the connection into LISTEN state */
+  netconn_listen(conn);
+  
+  do {
+    err = netconn_accept(conn, &newconn);
+    if (err == ERR_OK) {
+      http_server_netconn_serve(newconn);
+      netconn_delete(newconn);
+    }
+  } while(err == ERR_OK);
+  LWIP_DEBUGF(HTTPD_DEBUG,
+    ("http_server_netconn_thread: netconn_accept received error %d, shutting down",
+    err));
+  netconn_close(conn);
+  netconn_delete(conn);
+}
+
+/** Initialize the HTTP server (start its thread) */
+void
+http_server_netconn_init()
+{
+  sys_thread_new("http_server_netconn", http_server_netconn_thread, NULL, DEFAULT_THREAD_STACKSIZE, DEFAULT_THREAD_PRIO);
+}
+
+#endif /* LWIP_NETCONN*/

src/lwip-1.4.1/apps/httpserver/httpserver-netconn.h

@@ -0,0 +1,6 @@
+#ifndef __HTTPSERVER_NETCONN_H__
+#define __HTTPSERVER_NETCONN_H__
+
+void http_server_netconn_init();
+
+#endif /* __HTTPSERVER_NETCONN_H__ */

src/lwip-1.4.1/apps/httpserver_raw/fs.c

@@ -0,0 +1,180 @@
+/*
+ * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#include "lwip/opt.h"
+#include "lwip/def.h"
+#include "fs.h"
+#include "fsdata.h"
+#include <string.h>
+
+/** Set this to 1 to include "fsdata_custom.c" instead of "fsdata.c" for the
+ * file system (to prevent changing the file included in CVS) */
+#ifndef HTTPD_USE_CUSTOM_FSDATA
+#define HTTPD_USE_CUSTOM_FSDATA 0
+#endif
+
+#if HTTPD_USE_CUSTOM_FSDATA
+#include "fsdata_custom.c"
+#else /* HTTPD_USE_CUSTOM_FSDATA */
+#include "fsdata.c"
+#endif /* HTTPD_USE_CUSTOM_FSDATA */
+
+/*-----------------------------------------------------------------------------------*/
+
+#if LWIP_HTTPD_CUSTOM_FILES
+int fs_open_custom(struct fs_file *file, const char *name);
+void fs_close_custom(struct fs_file *file);
+#if LWIP_HTTPD_FS_ASYNC_READ
+u8_t fs_canread_custom(struct fs_file *file);
+u8_t fs_wait_read_custom(struct fs_file *file, fs_wait_cb callback_fn, void *callback_arg);
+#endif /* LWIP_HTTPD_FS_ASYNC_READ */
+#endif /* LWIP_HTTPD_CUSTOM_FILES */
+
+/*-----------------------------------------------------------------------------------*/
+err_t
+fs_open(struct fs_file *file, const char *name)
+{
+  const struct fsdata_file *f;
+
+  if ((file == NULL) || (name == NULL)) {
+     return ERR_ARG;
+  }
+
+#if LWIP_HTTPD_CUSTOM_FILES
+  if (fs_open_custom(file, name)) {
+    file->is_custom_file = 1;
+    return ERR_OK;
+  }
+  file->is_custom_file = 0;
+#endif /* LWIP_HTTPD_CUSTOM_FILES */
+
+  for (f = FS_ROOT; f != NULL; f = f->next) {
+    if (!strcmp(name, (char *)f->name)) {
+      file->data = (const char *)f->data;
+      file->len = f->len;
+      file->index = f->len;
+      file->pextension = NULL;
+      file->http_header_included = f->http_header_included;
+#if HTTPD_PRECALCULATED_CHECKSUM
+      file->chksum_count = f->chksum_count;
+      file->chksum = f->chksum;
+#endif /* HTTPD_PRECALCULATED_CHECKSUM */
+#if LWIP_HTTPD_FILE_STATE
+      file->state = fs_state_init(file, name);
+#endif /* #if LWIP_HTTPD_FILE_STATE */
+      return ERR_OK;
+    }
+  }
+  /* file not found */
+  return ERR_VAL;
+}
+
+/*-----------------------------------------------------------------------------------*/
+void
+fs_close(struct fs_file *file)
+{
+#if LWIP_HTTPD_CUSTOM_FILES
+  if (file->is_custom_file) {
+    fs_close_custom(file);
+  }
+#endif /* LWIP_HTTPD_CUSTOM_FILES */
+#if LWIP_HTTPD_FILE_STATE
+  fs_state_free(file, file->state);
+#endif /* #if LWIP_HTTPD_FILE_STATE */
+  LWIP_UNUSED_ARG(file);
+}
+/*-----------------------------------------------------------------------------------*/
+#if LWIP_HTTPD_DYNAMIC_FILE_READ
+#if LWIP_HTTPD_FS_ASYNC_READ
+int
+fs_read_async(struct fs_file *file, char *buffer, int count, fs_wait_cb callback_fn, void *callback_arg)
+#else /* LWIP_HTTPD_FS_ASYNC_READ */
+int
+fs_read(struct fs_file *file, char *buffer, int count)
+#endif /* LWIP_HTTPD_FS_ASYNC_READ */
+{
+  int read;
+
+  if(file->index == file->len) {
+    return FS_READ_EOF;
+  }
+#if LWIP_HTTPD_FS_ASYNC_READ
+#if LWIP_HTTPD_CUSTOM_FILES
+  if (!fs_canread_custom(file)) {
+    if (fs_wait_read_custom(file, callback_fn, callback_arg)) {
+      return FS_READ_DELAYED;
+    }
+  }
+#else /* LWIP_HTTPD_CUSTOM_FILES */
+  LWIP_UNUSED_ARG(callback_fn);
+  LWIP_UNUSED_ARG(callback_arg);
+#endif /* LWIP_HTTPD_CUSTOM_FILES */
+#endif /* LWIP_HTTPD_FS_ASYNC_READ */
+
+  read = file->len - file->index;
+  if(read > count) {
+    read = count;
+  }
+
+  MEMCPY(buffer, (file->data + file->index), read);
+  file->index += read;
+
+  return(read);
+}
+#endif /* LWIP_HTTPD_DYNAMIC_FILE_READ */
+/*-----------------------------------------------------------------------------------*/
+#if LWIP_HTTPD_FS_ASYNC_READ
+int
+fs_is_file_ready(struct fs_file *file, fs_wait_cb callback_fn, void *callback_arg)
+{
+  if (file != NULL) {
+#if LWIP_HTTPD_FS_ASYNC_READ
+#if LWIP_HTTPD_CUSTOM_FILES
+    if (!fs_canread_custom(file)) {
+      if (fs_wait_read_custom(file, callback_fn, callback_arg)) {
+        return 0;
+      }
+    }
+#else /* LWIP_HTTPD_CUSTOM_FILES */
+    LWIP_UNUSED_ARG(callback_fn);
+    LWIP_UNUSED_ARG(callback_arg);
+#endif /* LWIP_HTTPD_CUSTOM_FILES */
+#endif /* LWIP_HTTPD_FS_ASYNC_READ */
+  }
+  return 1;
+}
+#endif /* LWIP_HTTPD_FS_ASYNC_READ */
+/*-----------------------------------------------------------------------------------*/
+int
+fs_bytes_left(struct fs_file *file)
+{
+  return file->len - file->index;
+}

src/lwip-1.4.1/apps/httpserver_raw/fs.h

@@ -0,0 +1,132 @@
+/*
+ * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __FS_H__
+#define __FS_H__
+
+#include "lwip/opt.h"
+#include "lwip/err.h"
+
+/** Set this to 1 and provide the functions:
+ * - "int fs_open_custom(struct fs_file *file, const char *name)"
+ *    Called first for every opened file to allow opening files
+ *    that are not included in fsdata(_custom).c
+ * - "void fs_close_custom(struct fs_file *file)"
+ *    Called to free resources allocated by fs_open_custom().
+ */
+#ifndef LWIP_HTTPD_CUSTOM_FILES
+#define LWIP_HTTPD_CUSTOM_FILES       0
+#endif
+
+/** Set this to 1 to support fs_read() to dynamically read file data.
+ * Without this (default=off), only one-block files are supported,
+ * and the contents must be ready after fs_open().
+ */
+#ifndef LWIP_HTTPD_DYNAMIC_FILE_READ
+#define LWIP_HTTPD_DYNAMIC_FILE_READ  0
+#endif
+
+/** Set this to 1 to include an application state argument per file
+ * that is opened. This allows to keep a state per connection/file.
+ */
+#ifndef LWIP_HTTPD_FILE_STATE
+#define LWIP_HTTPD_FILE_STATE         0
+#endif
+
+/** HTTPD_PRECALCULATED_CHECKSUM==1: include precompiled checksums for
+ * predefined (MSS-sized) chunks of the files to prevent having to calculate
+ * the checksums at runtime. */
+#ifndef HTTPD_PRECALCULATED_CHECKSUM
+#define HTTPD_PRECALCULATED_CHECKSUM  0
+#endif
+
+/** LWIP_HTTPD_FS_ASYNC_READ==1: support asynchronous read operations
+ * (fs_read_async returns FS_READ_DELAYED and calls a callback when finished).
+ */
+#ifndef LWIP_HTTPD_FS_ASYNC_READ
+#define LWIP_HTTPD_FS_ASYNC_READ      0
+#endif
+
+#define FS_READ_EOF     -1
+#define FS_READ_DELAYED -2
+
+#if HTTPD_PRECALCULATED_CHECKSUM
+struct fsdata_chksum {
+  u32_t offset;
+  u16_t chksum;
+  u16_t len;
+};
+#endif /* HTTPD_PRECALCULATED_CHECKSUM */
+
+struct fs_file {
+  const char *data;
+  int len;
+  int index;
+  void *pextension;
+#if HTTPD_PRECALCULATED_CHECKSUM
+  const struct fsdata_chksum *chksum;
+  u16_t chksum_count;
+#endif /* HTTPD_PRECALCULATED_CHECKSUM */
+  u8_t http_header_included;
+#if LWIP_HTTPD_CUSTOM_FILES
+  u8_t is_custom_file;
+#endif /* LWIP_HTTPD_CUSTOM_FILES */
+#if LWIP_HTTPD_FILE_STATE
+  void *state;
+#endif /* LWIP_HTTPD_FILE_STATE */
+};
+
+#if LWIP_HTTPD_FS_ASYNC_READ
+typedef void (*fs_wait_cb)(void *arg);
+#endif /* LWIP_HTTPD_FS_ASYNC_READ */
+
+err_t fs_open(struct fs_file *file, const char *name);
+void fs_close(struct fs_file *file);
+#if LWIP_HTTPD_DYNAMIC_FILE_READ
+#if LWIP_HTTPD_FS_ASYNC_READ
+int fs_read_async(struct fs_file *file, char *buffer, int count, fs_wait_cb callback_fn, void *callback_arg);
+#else /* LWIP_HTTPD_FS_ASYNC_READ */
+int fs_read(struct fs_file *file, char *buffer, int count);
+#endif /* LWIP_HTTPD_FS_ASYNC_READ */
+#endif /* LWIP_HTTPD_DYNAMIC_FILE_READ */
+#if LWIP_HTTPD_FS_ASYNC_READ
+int fs_is_file_ready(struct fs_file *file, fs_wait_cb callback_fn, void *callback_arg);
+#endif /* LWIP_HTTPD_FS_ASYNC_READ */
+int fs_bytes_left(struct fs_file *file);
+
+#if LWIP_HTTPD_FILE_STATE
+/** This user-defined function is called when a file is opened. */
+void *fs_state_init(struct fs_file *file, const char *name);
+/** This user-defined function is called when a file is closed. */
+void fs_state_free(struct fs_file *file, void *state);
+#endif /* #if LWIP_HTTPD_FILE_STATE */
+
+#endif /* __FS_H__ */

src/lwip-1.4.1/apps/httpserver_raw/fs/404.html

@@ -0,0 +1,21 @@
+<html>
+<head><title>lwIP - A Lightweight TCP/IP Stack</title></head>
+<body bgcolor="white" text="black">
+
+    <table width="100%">
+      <tr valign="top"><td width="80">	  
+	  <a href="http://www.sics.se/"><img src="/img/sics.gif"
+	  border="0" alt="SICS logo" title="SICS logo"></a>
+	</td><td width="500">	  
+	  <h1>lwIP - A Lightweight TCP/IP Stack</h1>
+	  <h2>404 - Page not found</h2>
+	  <p>
+	    Sorry, the page you are requesting was not found on this
+	    server. 
+	  </p>
+	</td><td>
+	  &nbsp;
+	</td></tr>
+      </table>
+</body>
+</html>

src/lwip-1.4.1/apps/httpserver_raw/fs/index.html

@@ -0,0 +1,47 @@
+<html>
+<head><title>lwIP - A Lightweight TCP/IP Stack</title></head>
+<body bgcolor="white" text="black">
+
+    <table width="100%">
+      <tr valign="top"><td width="80">	  
+	  <a href="http://www.sics.se/"><img src="/img/sics.gif"
+	  border="0" alt="SICS logo" title="SICS logo"></a>
+	</td><td width="500">	  
+	  <h1>lwIP - A Lightweight TCP/IP Stack</h1>
+	  <p>
+	    The web page you are watching was served by a simple web
+	    server running on top of the lightweight TCP/IP stack <a
+	    href="http://www.sics.se/~adam/lwip/">lwIP</a>.
+	  </p>
+	  <p>
+	    lwIP is an open source implementation of the TCP/IP
+	    protocol suite that was originally written by <a
+	    href="http://www.sics.se/~adam/lwip/">Adam Dunkels
+	    of the Swedish Institute of Computer Science</a> but now is
+	    being actively developed by a team of developers
+	    distributed world-wide. Since it's release, lwIP has
+	    spurred a lot of interest and has been ported to several
+	    platforms and operating systems. lwIP can be used either
+	    with or without an underlying OS.
+	  </p>
+	  <p>
+	    The focus of the lwIP TCP/IP implementation is to reduce
+	    the RAM usage while still having a full scale TCP. This
+	    makes lwIP suitable for use in embedded systems with tens
+	    of kilobytes of free RAM and room for around 40 kilobytes
+	    of code ROM.
+	  </p>
+	  <p>
+	    More information about lwIP can be found at the lwIP
+	    homepage at <a
+	    href="http://savannah.nongnu.org/projects/lwip/">http://savannah.nongnu.org/projects/lwip/</a>
+	    or at the lwIP wiki at <a
+	    href="http://lwip.wikia.com/">http://lwip.wikia.com/</a>.
+	  </p>
+	</td><td>
+	  &nbsp;
+	</td></tr>
+      </table>
+</body>
+</html>
+

src/lwip-1.4.1/apps/httpserver_raw/fsdata.h

@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __FSDATA_H__
+#define __FSDATA_H__
+
+#include "lwip/opt.h"
+#include "fs.h"
+
+struct fsdata_file {
+  const struct fsdata_file *next;
+  const unsigned char *name;
+  const unsigned char *data;
+  int len;
+  u8_t http_header_included;
+#if HTTPD_PRECALCULATED_CHECKSUM
+  u16_t chksum_count;
+  const struct fsdata_chksum *chksum;
+#endif /* HTTPD_PRECALCULATED_CHECKSUM */
+};
+
+#endif /* __FSDATA_H__ */

src/lwip-1.4.1/apps/httpserver_raw/httpd.h

@@ -0,0 +1,236 @@
+/*
+ * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ * This version of the file has been modified by Texas Instruments to offer
+ * simple server-side-include (SSI) and Common Gateway Interface (CGI)
+ * capability.
+ */
+
+#ifndef __HTTPD_H__
+#define __HTTPD_H__
+
+#include "lwip/opt.h"
+#include "lwip/err.h"
+#include "lwip/pbuf.h"
+
+
+/** Set this to 1 to support CGI */
+#ifndef LWIP_HTTPD_CGI
+#define LWIP_HTTPD_CGI            0
+#endif
+
+/** Set this to 1 to support SSI (Server-Side-Includes) */
+#ifndef LWIP_HTTPD_SSI
+#define LWIP_HTTPD_SSI            0
+#endif
+
+/** Set this to 1 to support HTTP POST */
+#ifndef LWIP_HTTPD_SUPPORT_POST
+#define LWIP_HTTPD_SUPPORT_POST   0
+#endif
+
+
+#if LWIP_HTTPD_CGI
+
+/*
+ * Function pointer for a CGI script handler.
+ *
+ * This function is called each time the HTTPD server is asked for a file
+ * whose name was previously registered as a CGI function using a call to
+ * http_set_cgi_handler. The iIndex parameter provides the index of the
+ * CGI within the ppcURLs array passed to http_set_cgi_handler. Parameters
+ * pcParam and pcValue provide access to the parameters provided along with
+ * the URI. iNumParams provides a count of the entries in the pcParam and
+ * pcValue arrays. Each entry in the pcParam array contains the name of a
+ * parameter with the corresponding entry in the pcValue array containing the
+ * value for that parameter. Note that pcParam may contain multiple elements
+ * with the same name if, for example, a multi-selection list control is used
+ * in the form generating the data.
+ *
+ * The function should return a pointer to a character string which is the
+ * path and filename of the response that is to be sent to the connected
+ * browser, for example "/thanks.htm" or "/response/error.ssi".
+ *
+ * The maximum number of parameters that will be passed to this function via
+ * iNumParams is defined by LWIP_HTTPD_MAX_CGI_PARAMETERS. Any parameters in the incoming
+ * HTTP request above this number will be discarded.
+ *
+ * Requests intended for use by this CGI mechanism must be sent using the GET
+ * method (which encodes all parameters within the URI rather than in a block
+ * later in the request). Attempts to use the POST method will result in the
+ * request being ignored.
+ *
+ */
+typedef const char *(*tCGIHandler)(int iIndex, int iNumParams, char *pcParam[],
+                             char *pcValue[]);
+
+/*
+ * Structure defining the base filename (URL) of a CGI and the associated
+ * function which is to be called when that URL is requested.
+ */
+typedef struct
+{
+    const char *pcCGIName;
+    tCGIHandler pfnCGIHandler;
+} tCGI;
+
+void http_set_cgi_handlers(const tCGI *pCGIs, int iNumHandlers);
+
+
+/* The maximum number of parameters that the CGI handler can be sent. */
+#ifndef LWIP_HTTPD_MAX_CGI_PARAMETERS
+#define LWIP_HTTPD_MAX_CGI_PARAMETERS 16
+#endif
+
+#endif /* LWIP_HTTPD_CGI */
+
+#if LWIP_HTTPD_SSI
+
+/** LWIP_HTTPD_SSI_MULTIPART==1: SSI handler function is called with 2 more
+ * arguments indicating a counter for insert string that are too long to be
+ * inserted at once: the SSI handler function must then set 'next_tag_part'
+ * which will be passed back to it in the next call. */
+#ifndef LWIP_HTTPD_SSI_MULTIPART
+#define LWIP_HTTPD_SSI_MULTIPART    0
+#endif
+
+/*
+ * Function pointer for the SSI tag handler callback.
+ *
+ * This function will be called each time the HTTPD server detects a tag of the
+ * form <!--#name--> in a .shtml, .ssi or .shtm file where "name" appears as
+ * one of the tags supplied to http_set_ssi_handler in the ppcTags array.  The
+ * returned insert string, which will be appended after the the string
+ * "<!--#name-->" in file sent back to the client,should be written to pointer
+ * pcInsert.  iInsertLen contains the size of the buffer pointed to by
+ * pcInsert.  The iIndex parameter provides the zero-based index of the tag as
+ * found in the ppcTags array and identifies the tag that is to be processed.
+ *
+ * The handler returns the number of characters written to pcInsert excluding
+ * any terminating NULL or a negative number to indicate a failure (tag not
+ * recognized, for example).
+ *
+ * Note that the behavior of this SSI mechanism is somewhat different from the
+ * "normal" SSI processing as found in, for example, the Apache web server.  In
+ * this case, the inserted text is appended following the SSI tag rather than
+ * replacing the tag entirely.  This allows for an implementation that does not
+ * require significant additional buffering of output data yet which will still
+ * offer usable SSI functionality.  One downside to this approach is when
+ * attempting to use SSI within JavaScript.  The SSI tag is structured to
+ * resemble an HTML comment but this syntax does not constitute a comment
+ * within JavaScript and, hence, leaving the tag in place will result in
+ * problems in these cases.  To work around this, any SSI tag which needs to
+ * output JavaScript code must do so in an encapsulated way, sending the whole
+ * HTML <script>...</script> section as a single include.
+ */
+typedef u16_t (*tSSIHandler)(int iIndex, char *pcInsert, int iInsertLen
+#if LWIP_HTTPD_SSI_MULTIPART
+                             , u16_t current_tag_part, u16_t *next_tag_part
+#endif /* LWIP_HTTPD_SSI_MULTIPART */
+#if LWIP_HTTPD_FILE_STATE
+                             , void *connection_state
+#endif /* LWIP_HTTPD_FILE_STATE */
+                             );
+
+void http_set_ssi_handler(tSSIHandler pfnSSIHandler,
+                          const char **ppcTags, int iNumTags);
+
+/* The maximum length of the string comprising the tag name */
+#ifndef LWIP_HTTPD_MAX_TAG_NAME_LEN
+#define LWIP_HTTPD_MAX_TAG_NAME_LEN 8
+#endif
+
+/* The maximum length of string that can be returned to replace any given tag */
+#ifndef LWIP_HTTPD_MAX_TAG_INSERT_LEN
+#define LWIP_HTTPD_MAX_TAG_INSERT_LEN 192
+#endif
+
+#endif /* LWIP_HTTPD_SSI */
+
+#if LWIP_HTTPD_SUPPORT_POST
+
+/* These functions must be implemented by the application */
+
+/** Called when a POST request has been received. The application can decide
+ * whether to accept it or not.
+ *
+ * @param connection Unique connection identifier, valid until httpd_post_end
+ *        is called.
+ * @param uri The HTTP header URI receiving the POST request.
+ * @param http_request The raw HTTP request (the first packet, normally).
+ * @param http_request_len Size of 'http_request'.
+ * @param content_len Content-Length from HTTP header.
+ * @param response_uri Filename of response file, to be filled when denying the
+ *        request
+ * @param response_uri_len Size of the 'response_uri' buffer.
+ * @param post_auto_wnd Set this to 0 to let the callback code handle window
+ *        updates by calling 'httpd_post_data_recved' (to throttle rx speed)
+ *        default is 1 (httpd handles window updates automatically)
+ * @return ERR_OK: Accept the POST request, data may be passed in
+ *         another err_t: Deny the POST request, send back 'bad request'.
+ */
+err_t httpd_post_begin(void *connection, const char *uri, const char *http_request,
+                       u16_t http_request_len, int content_len, char *response_uri,
+                       u16_t response_uri_len, u8_t *post_auto_wnd);
+
+/** Called for each pbuf of data that has been received for a POST.
+ * ATTENTION: The application is responsible for freeing the pbufs passed in!
+ *
+ * @param connection Unique connection identifier.
+ * @param p Received data.
+ * @return ERR_OK: Data accepted.
+ *         another err_t: Data denied, http_post_get_response_uri will be called.
+ */
+err_t httpd_post_receive_data(void *connection, struct pbuf *p);
+
+/** Called when all data is received or when the connection is closed.
+ * The application must return the filename/URI of a file to send in response
+ * to this POST request. If the response_uri buffer is untouched, a 404
+ * response is returned.
+ *
+ * @param connection Unique connection identifier.
+ * @param response_uri Filename of response file, to be filled when denying the request
+ * @param response_uri_len Size of the 'response_uri' buffer.
+ */
+void httpd_post_finished(void *connection, char *response_uri, u16_t response_uri_len);
+
+#ifndef LWIP_HTTPD_POST_MANUAL_WND
+#define LWIP_HTTPD_POST_MANUAL_WND  0
+#endif
+
+#if LWIP_HTTPD_POST_MANUAL_WND
+void httpd_post_data_recved(void *connection, u16_t recved_len);
+#endif /* LWIP_HTTPD_POST_MANUAL_WND */
+
+#endif /* LWIP_HTTPD_SUPPORT_POST */
+
+void httpd_init(void);
+
+#endif /* __HTTPD_H__ */

src/lwip-1.4.1/apps/httpserver_raw/httpd_structs.h

@@ -0,0 +1,132 @@
+#ifndef __HTTPD_STRUCTS_H__
+#define __HTTPD_STRUCTS_H__
+
+#include "httpd.h"
+
+/** This string is passed in the HTTP header as "Server: " */
+#ifndef HTTPD_SERVER_AGENT
+#define HTTPD_SERVER_AGENT "lwIP/1.3.1 (http://savannah.nongnu.org/projects/lwip)"
+#endif
+
+/** Set this to 1 if you want to include code that creates HTTP headers
+ * at runtime. Default is off: HTTP headers are then created statically
+ * by the makefsdata tool. Static headers mean smaller code size, but
+ * the (readonly) fsdata will grow a bit as every file includes the HTTP
+ * header. */
+#ifndef LWIP_HTTPD_DYNAMIC_HEADERS
+#define LWIP_HTTPD_DYNAMIC_HEADERS 0
+#endif
+
+
+#if LWIP_HTTPD_DYNAMIC_HEADERS
+/** This struct is used for a list of HTTP header strings for various
+ * filename extensions. */
+typedef struct
+{
+  const char *extension;
+  int headerIndex;
+} tHTTPHeader;
+
+/** A list of strings used in HTTP headers */
+static const char * const g_psHTTPHeaderStrings[] =
+{
+ "Content-type: text/html\r\n\r\n",
+ "Content-type: text/html\r\nExpires: Fri, 10 Apr 2008 14:00:00 GMT\r\nPragma: no-cache\r\n\r\n",
+ "Content-type: image/gif\r\n\r\n",
+ "Content-type: image/png\r\n\r\n",
+ "Content-type: image/jpeg\r\n\r\n",
+ "Content-type: image/bmp\r\n\r\n",
+ "Content-type: image/x-icon\r\n\r\n",
+ "Content-type: application/octet-stream\r\n\r\n",
+ "Content-type: application/x-javascript\r\n\r\n",
+ "Content-type: application/x-javascript\r\n\r\n",
+ "Content-type: text/css\r\n\r\n",
+ "Content-type: application/x-shockwave-flash\r\n\r\n",
+ "Content-type: text/xml\r\n\r\n",
+ "Content-type: text/plain\r\n\r\n",
+ "HTTP/1.0 200 OK\r\n",
+ "HTTP/1.0 404 File not found\r\n",
+ "HTTP/1.0 400 Bad Request\r\n",
+ "HTTP/1.0 501 Not Implemented\r\n",
+ "HTTP/1.1 200 OK\r\n",
+ "HTTP/1.1 404 File not found\r\n",
+ "HTTP/1.1 400 Bad Request\r\n",
+ "HTTP/1.1 501 Not Implemented\r\n",
+ "Content-Length: ",
+ "Connection: Close\r\n",
+ "Connection: keep-alive\r\n",
+ "Server: "HTTPD_SERVER_AGENT"\r\n",
+ "\r\n<html><body><h2>404: The requested file cannot be found.</h2></body></html>\r\n",
+
+ "Content-type: image/svg+xml\r\n\r\n"
+};
+
+/* Indexes into the g_psHTTPHeaderStrings array */
+#define HTTP_HDR_HTML           0  /* text/html */
+#define HTTP_HDR_SSI            1  /* text/html Expires... */
+#define HTTP_HDR_GIF            2  /* image/gif */
+#define HTTP_HDR_PNG            3  /* image/png */
+#define HTTP_HDR_JPG            4  /* image/jpeg */
+#define HTTP_HDR_BMP            5  /* image/bmp */
+#define HTTP_HDR_ICO            6  /* image/x-icon */
+#define HTTP_HDR_APP            7  /* application/octet-stream */
+#define HTTP_HDR_JS             8  /* application/x-javascript */
+#define HTTP_HDR_RA             9  /* application/x-javascript */
+#define HTTP_HDR_CSS            10 /* text/css */
+#define HTTP_HDR_SWF            11 /* application/x-shockwave-flash */
+#define HTTP_HDR_XML            12 /* text/xml */
+#define HTTP_HDR_DEFAULT_TYPE   13 /* text/plain */
+#define HTTP_HDR_OK             14 /* 200 OK */
+#define HTTP_HDR_NOT_FOUND      15 /* 404 File not found */
+#define HTTP_HDR_BAD_REQUEST    16 /* 400 Bad request */
+#define HTTP_HDR_NOT_IMPL       17 /* 501 Not Implemented */
+#define HTTP_HDR_OK_11          18 /* 200 OK */
+#define HTTP_HDR_NOT_FOUND_11   19 /* 404 File not found */
+#define HTTP_HDR_BAD_REQUEST_11 20 /* 400 Bad request */
+#define HTTP_HDR_NOT_IMPL_11    21 /* 501 Not Implemented */
+#define HTTP_HDR_CONTENT_LENGTH 22 /* Content-Length: (HTTP 1.1)*/
+#define HTTP_HDR_CONN_CLOSE     23 /* Connection: Close (HTTP 1.1) */
+#define HTTP_HDR_CONN_KEEPALIVE 24 /* Connection: keep-alive (HTTP 1.1) */
+#define HTTP_HDR_SERVER         25 /* Server: HTTPD_SERVER_AGENT */
+#define DEFAULT_404_HTML        26 /* default 404 body */
+
+/* added by FSE: */
+#define HTTP_HDR_SVG            27  /* image/svg+xml */
+
+
+/** A list of extension-to-HTTP header strings */
+const static tHTTPHeader g_psHTTPHeaders[] =
+{
+ { "html", HTTP_HDR_HTML},
+ { "htm",  HTTP_HDR_HTML},
+ { "shtml",HTTP_HDR_SSI},
+ { "shtm", HTTP_HDR_SSI},
+ { "ssi",  HTTP_HDR_SSI},
+ { "gif",  HTTP_HDR_GIF},
+ { "png",  HTTP_HDR_PNG},
+ { "jpg",  HTTP_HDR_JPG},
+ { "bmp",  HTTP_HDR_BMP},
+ { "ico",  HTTP_HDR_ICO},
+ { "class",HTTP_HDR_APP},
+ { "cls",  HTTP_HDR_APP},
+ { "js",   HTTP_HDR_JS},
+ { "ram",  HTTP_HDR_RA},
+ { "css",  HTTP_HDR_CSS},
+ { "swf",  HTTP_HDR_SWF},
+ { "xml",  HTTP_HDR_XML},
+ { "xsl",  HTTP_HDR_XML},
+ { "svg",  HTTP_HDR_SVG}
+};
+
+#define NUM_HTTP_HEADERS (sizeof(g_psHTTPHeaders) / sizeof(tHTTPHeader))
+
+#endif /* LWIP_HTTPD_DYNAMIC_HEADERS */
+
+#if LWIP_HTTPD_SSI
+static const char * const g_pcSSIExtensions[] = {
+  ".shtml", ".shtm", ".ssi", ".xml"
+};
+#define NUM_SHTML_EXTENSIONS (sizeof(g_pcSSIExtensions) / sizeof(const char *))
+#endif /* LWIP_HTTPD_SSI */
+
+#endif /* __HTTPD_STRUCTS_H__ */

src/lwip-1.4.1/apps/httpserver_raw/makefsdata/makefsdata

@@ -0,0 +1,97 @@
+#!/usr/bin/perl
+
+open(OUTPUT, "> fsdata.c");
+
+chdir("fs");
+open(FILES, "find . -type f |");
+
+while($file = <FILES>) {
+
+    # Do not include files in CVS directories nor backup files.
+    if($file =~ /(CVS|~)/) {
+    	next;
+    }
+    
+    chop($file);
+    
+    open(HEADER, "> /tmp/header") || die $!;
+    if($file =~ /404/) {
+	print(HEADER "HTTP/1.0 404 File not found\r\n");
+    } else {
+	print(HEADER "HTTP/1.0 200 OK\r\n");
+    }
+    print(HEADER "Server: lwIP/pre-0.6 (http://www.sics.se/~adam/lwip/)\r\n");
+    if($file =~ /\.html$/) {
+	print(HEADER "Content-type: text/html\r\n");
+    } elsif($file =~ /\.gif$/) {
+	print(HEADER "Content-type: image/gif\r\n");
+    } elsif($file =~ /\.png$/) {
+	print(HEADER "Content-type: image/png\r\n");
+    } elsif($file =~ /\.jpg$/) {
+	print(HEADER "Content-type: image/jpeg\r\n");
+    } elsif($file =~ /\.class$/) {
+	print(HEADER "Content-type: application/octet-stream\r\n");
+    } elsif($file =~ /\.ram$/) {
+	print(HEADER "Content-type: audio/x-pn-realaudio\r\n");    
+    } else {
+	print(HEADER "Content-type: text/plain\r\n");
+    }
+    print(HEADER "\r\n");
+    close(HEADER);
+
+    unless($file =~ /\.plain$/ || $file =~ /cgi/) {
+	system("cat /tmp/header $file > /tmp/file");
+    } else {
+	system("cp $file /tmp/file");
+    }
+    
+    open(FILE, "/tmp/file");
+    unlink("/tmp/file");
+    unlink("/tmp/header");
+
+    $file =~ s/\.//;
+    $fvar = $file;
+    $fvar =~ s-/-_-g;
+    $fvar =~ s-\.-_-g;
+    print(OUTPUT "static const unsigned char data".$fvar."[] = {\n");
+    print(OUTPUT "\t/* $file */\n\t");
+    for($j = 0; $j < length($file); $j++) {
+	printf(OUTPUT "%#02x, ", unpack("C", substr($file, $j, 1)));
+    }
+    printf(OUTPUT "0,\n");
+    
+    
+    $i = 0;
+    while(read(FILE, $data, 1)) {
+        if($i == 0) {
+            print(OUTPUT "\t");
+        }
+        printf(OUTPUT "%#02x, ", unpack("C", $data));
+        $i++;
+        if($i == 10) {
+            print(OUTPUT "\n");
+            $i = 0;
+        }
+    }
+    print(OUTPUT "};\n\n");
+    close(FILE);
+    push(@fvars, $fvar);
+    push(@files, $file);
+}
+
+for($i = 0; $i < @fvars; $i++) {
+    $file = $files[$i];
+    $fvar = $fvars[$i];
+
+    if($i == 0) {
+        $prevfile = "NULL";
+    } else {
+        $prevfile = "file" . $fvars[$i - 1];
+    }
+    print(OUTPUT "const struct fsdata_file file".$fvar."[] = {{$prevfile, data$fvar, ");
+    print(OUTPUT "data$fvar + ". (length($file) + 1) .", ");
+    print(OUTPUT "sizeof(data$fvar) - ". (length($file) + 1) ."}};\n\n");
+}
+
+print(OUTPUT "#define FS_ROOT file$fvars[$i - 1]\n\n");
+print(OUTPUT "#define FS_NUMFILES $i\n");

src/lwip-1.4.1/apps/httpserver_raw/makefsdata/makefsdata.c

@@ -0,0 +1,636 @@
+/**
+ * makefsdata: Converts a directory structure for use with the lwIP httpd.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Jim Pettinato
+ *         Simon Goldschmidt
+ *
+ * @todo:
+ * - take TCP_MSS, LWIP_TCP_TIMESTAMPS and
+ *   PAYLOAD_ALIGN_TYPE/PAYLOAD_ALIGNMENT as arguments
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef WIN32
+#define WIN32_LEAN_AND_MEAN
+#include "windows.h"
+#else
+#include <dir.h>
+#endif
+#include <dos.h>
+#include <string.h>
+
+/* Compatibility defines Win32 vs. DOS */
+#ifdef WIN32
+
+#define FIND_T                        WIN32_FIND_DATAA
+#define FIND_T_FILENAME(fInfo)        (fInfo.cFileName)
+#define FIND_T_IS_DIR(fInfo)          ((fInfo.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0)
+#define FIND_T_IS_FILE(fInfo)         ((fInfo.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) == 0)
+#define FIND_RET_T                    HANDLE
+#define FINDFIRST_FILE(path, result)  FindFirstFileA(path, result)
+#define FINDFIRST_DIR(path, result)   FindFirstFileA(path, result)
+#define FINDNEXT(ff_res, result)      FindNextFileA(ff_res, result)
+#define FINDFIRST_SUCCEEDED(ret)      (ret != INVALID_HANDLE_VALUE)
+#define FINDNEXT_SUCCEEDED(ret)       (ret == TRUE)
+
+#define GETCWD(path, len)             GetCurrentDirectoryA(len, path)
+#define CHDIR(path)                   SetCurrentDirectoryA(path)
+
+#define NEWLINE     "\r\n"
+#define NEWLINE_LEN 2
+
+#else
+
+#define FIND_T                        struct ffblk
+#define FIND_T_FILENAME(fInfo)        (fInfo.ff_name)
+#define FIND_T_IS_DIR(fInfo)          ((fInfo.ff_attrib & FA_DIREC) == FA_DIREC)
+#define FIND_T_IS_FILE(fInfo)         (1)
+#define FIND_RET_T                    int
+#define FINDFIRST_FILE(path, result)  findfirst(path, result, FA_ARCH)
+#define FINDFIRST_DIR(path, result)   findfirst(path, result, FA_DIREC)
+#define FINDNEXT(ff_res, result)      FindNextFileA(ff_res, result)
+#define FINDFIRST_SUCCEEDED(ret)      (ret == 0)
+#define FINDNEXT_SUCCEEDED(ret)       (ret == 0)
+
+#define GETCWD(path, len)             getcwd(path, len)
+#define CHDIR(path)                   chdir(path)
+
+#endif
+
+/* define this to get the header variables we use to build HTTP headers */
+#define LWIP_HTTPD_DYNAMIC_HEADERS 1
+#define LWIP_HTTPD_SSI             1
+#include "../httpd_structs.h"
+
+#include "../../../../lwip/src/core/ipv4/inet_chksum.c"
+#include "../../../../lwip/src/core/def.c"
+
+/** (Your server name here) */
+const char *serverID = "Server: "HTTPD_SERVER_AGENT"\r\n";
+
+/* change this to suit your MEM_ALIGNMENT */
+#define PAYLOAD_ALIGNMENT 4
+/* set this to 0 to prevent aligning payload */
+#define ALIGN_PAYLOAD 1
+/* define this to a type that has the required alignment */
+#define PAYLOAD_ALIGN_TYPE "unsigned int"
+static int payload_alingment_dummy_counter = 0;
+
+#define HEX_BYTES_PER_LINE 16
+
+#define MAX_PATH_LEN 256
+
+#define COPY_BUFSIZE 10240
+
+int process_sub(FILE *data_file, FILE *struct_file);
+int process_file(FILE *data_file, FILE *struct_file, const char *filename);
+int file_write_http_header(FILE *data_file, const char *filename, int file_size,
+                           u16_t *http_hdr_len, u16_t *http_hdr_chksum);
+int file_put_ascii(FILE *file, const char *ascii_string, int len, int *i);
+int s_put_ascii(char *buf, const char *ascii_string, int len, int *i);
+void concat_files(const char *file1, const char *file2, const char *targetfile);
+
+static unsigned char file_buffer_raw[COPY_BUFSIZE];
+/* 5 bytes per char + 3 bytes per line */
+static char file_buffer_c[COPY_BUFSIZE * 5 + ((COPY_BUFSIZE / HEX_BYTES_PER_LINE) * 3)];
+
+char curSubdir[MAX_PATH_LEN];
+char lastFileVar[MAX_PATH_LEN];
+char hdr_buf[4096];
+
+unsigned char processSubs = 1;
+unsigned char includeHttpHeader = 1;
+unsigned char useHttp11 = 0;
+unsigned char supportSsi = 1;
+unsigned char precalcChksum = 0;
+
+int main(int argc, char *argv[])
+{
+  FIND_T fInfo;
+  FIND_RET_T fret;
+  char path[MAX_PATH_LEN];
+  char appPath[MAX_PATH_LEN];
+  FILE *data_file;
+  FILE *struct_file;
+  int filesProcessed;
+  int i;
+  char targetfile[MAX_PATH_LEN];
+  strcpy(targetfile, "fsdata.c");
+
+  memset(path, 0, sizeof(path));
+  memset(appPath, 0, sizeof(appPath));
+
+  printf(NEWLINE " makefsdata - HTML to C source converter" NEWLINE);
+  printf("     by Jim Pettinato               - circa 2003 " NEWLINE);
+  printf("     extended by Simon Goldschmidt  - 2009 " NEWLINE NEWLINE);
+
+  strcpy(path, "fs");
+  for(i = 1; i < argc; i++) {
+    if (argv[i][0] == '-') {
+      if (strstr(argv[i], "-s")) {
+        processSubs = 0;
+      } else if (strstr(argv[i], "-e")) {
+        includeHttpHeader = 0;
+      } else if (strstr(argv[i], "-11")) {
+        useHttp11 = 1;
+      } else if (strstr(argv[i], "-nossi")) {
+        supportSsi = 0;
+      } else if (strstr(argv[i], "-c")) {
+        precalcChksum = 1;
+      } else if((argv[i][1] == 'f') && (argv[i][2] == ':')) {
+        strcpy(targetfile, &argv[i][3]);
+        printf("Writing to file \"%s\"\n", targetfile);
+      }
+    } else {
+      strcpy(path, argv[i]);
+    }
+  }
+
+  /* if command line param or subdir named 'fs' not found spout usage verbiage */
+  fret = FINDFIRST_DIR(path, &fInfo);
+  if (!FINDFIRST_SUCCEEDED(fret)) {
+    /* if no subdir named 'fs' (or the one which was given) exists, spout usage verbiage */
+    printf(" Failed to open directory \"%s\"." NEWLINE NEWLINE, path);
+    printf(" Usage: htmlgen [targetdir] [-s] [-i] [-f:<filename>]" NEWLINE NEWLINE);
+    printf("   targetdir: relative or absolute path to files to convert" NEWLINE);
+    printf("   switch -s: toggle processing of subdirectories (default is on)" NEWLINE);
+    printf("   switch -e: exclude HTTP header from file (header is created at runtime, default is off)" NEWLINE);
+    printf("   switch -11: include HTTP 1.1 header (1.0 is default)" NEWLINE);
+    printf("   switch -nossi: no support for SSI (cannot calculate Content-Length for SSI)" NEWLINE);
+    printf("   switch -c: precalculate checksums for all pages (default is off)" NEWLINE);
+    printf("   switch -f: target filename (default is \"fsdata.c\")" NEWLINE);
+    printf("   if targetdir not specified, htmlgen will attempt to" NEWLINE);
+    printf("   process files in subdirectory 'fs'" NEWLINE);
+    exit(-1);
+  }
+
+  printf("HTTP %sheader will %s statically included." NEWLINE,
+    (includeHttpHeader ? (useHttp11 ? "1.1 " : "1.0 ") : ""),
+    (includeHttpHeader ? "be" : "not be"));
+
+  sprintf(curSubdir, "");  /* start off in web page's root directory - relative paths */
+  printf("  Processing all files in directory %s", path);
+  if (processSubs) {
+    printf(" and subdirectories..." NEWLINE NEWLINE);
+  } else {
+    printf("..." NEWLINE NEWLINE);
+  }
+
+  GETCWD(appPath, MAX_PATH_LEN);
+  data_file = fopen("fsdata.tmp", "wb");
+  if (data_file == NULL) {
+    printf("Failed to create file \"fsdata.tmp\"\n");
+    exit(-1);
+  }
+  struct_file = fopen("fshdr.tmp", "wb");
+  if (struct_file == NULL) {
+    printf("Failed to create file \"fshdr.tmp\"\n");
+    exit(-1);
+  }
+
+  CHDIR(path);
+
+  fprintf(data_file, "#include \"fs.h\"" NEWLINE);
+  fprintf(data_file, "#include \"lwip/def.h\"" NEWLINE);
+  fprintf(data_file, "#include \"fsdata.h\"" NEWLINE NEWLINE NEWLINE);
+
+  fprintf(data_file, "#define file_NULL (struct fsdata_file *) NULL" NEWLINE NEWLINE NEWLINE);
+
+  sprintf(lastFileVar, "NULL");
+
+  filesProcessed = process_sub(data_file, struct_file);
+
+  /* data_file now contains all of the raw data.. now append linked list of
+   * file header structs to allow embedded app to search for a file name */
+  fprintf(data_file, NEWLINE NEWLINE);
+  fprintf(struct_file, "#define FS_ROOT file_%s" NEWLINE, lastFileVar);
+  fprintf(struct_file, "#define FS_NUMFILES %d" NEWLINE NEWLINE, filesProcessed);
+
+  fclose(data_file);
+  fclose(struct_file);
+
+  CHDIR(appPath);
+  /* append struct_file to data_file */
+  printf(NEWLINE "Creating target file..." NEWLINE NEWLINE);
+  concat_files("fsdata.tmp", "fshdr.tmp", targetfile);
+
+  /* if succeeded, delete the temporary files */
+  remove("fsdata.tmp");
+  remove("fshdr.tmp"); 
+
+  printf(NEWLINE "Processed %d files - done." NEWLINE NEWLINE, filesProcessed);
+
+  return 0;
+}
+
+static void copy_file(const char *filename_in, FILE *fout)
+{
+  FILE *fin;
+  size_t len;
+  fin = fopen(filename_in, "rb");
+  if (fin == NULL) {
+    printf("Failed to open file \"%s\"\n", filename_in);
+    exit(-1);
+  }
+
+  while((len = fread(file_buffer_raw, 1, COPY_BUFSIZE, fin)) > 0)
+  {
+    fwrite(file_buffer_raw, 1, len, fout);
+  }
+  fclose(fin);
+}
+
+void concat_files(const char *file1, const char *file2, const char *targetfile)
+{
+  FILE *fout;
+  fout = fopen(targetfile, "wb");
+  if (fout == NULL) {
+    printf("Failed to open file \"%s\"\n", targetfile);
+    exit(-1);
+  }
+  copy_file(file1, fout);
+  copy_file(file2, fout);
+  fclose(fout);
+}
+
+int process_sub(FILE *data_file, FILE *struct_file)
+{
+  FIND_T fInfo;
+  FIND_RET_T fret;
+  int filesProcessed = 0;
+  char oldSubdir[MAX_PATH_LEN];
+
+  if (processSubs) {
+    /* process subs recursively */
+    strcpy(oldSubdir, curSubdir);
+    fret = FINDFIRST_DIR("*", &fInfo);
+    if (FINDFIRST_SUCCEEDED(fret)) {
+      do {
+        const char *curName = FIND_T_FILENAME(fInfo);
+        if (curName == NULL) continue;
+        if (curName[0] == '.') continue;
+        if (strcmp(curName, "CVS") == 0) continue;
+        if (!FIND_T_IS_DIR(fInfo)) continue;
+        CHDIR(curName);
+        strcat(curSubdir, "/");
+        strcat(curSubdir, curName);
+        printf(NEWLINE "processing subdirectory %s/..." NEWLINE, curSubdir);
+        filesProcessed += process_sub(data_file, struct_file);
+        CHDIR("..");
+        strcpy(curSubdir, oldSubdir);
+      } while (FINDNEXT_SUCCEEDED(FINDNEXT(fret, &fInfo)));
+    }
+  }
+
+  fret = FINDFIRST_FILE("*.*", &fInfo);
+  if (FINDFIRST_SUCCEEDED(fret)) {
+    /* at least one file in directory */
+    do {
+      if (FIND_T_IS_FILE(fInfo)) {
+        const char *curName = FIND_T_FILENAME(fInfo);
+        printf("processing %s/%s..." NEWLINE, curSubdir, curName);
+        if (process_file(data_file, struct_file, curName) < 0) {
+          printf(NEWLINE "Error... aborting" NEWLINE);
+          return -1;
+        }
+        filesProcessed++;
+      }
+    } while (FINDNEXT_SUCCEEDED(FINDNEXT(fret, &fInfo)));
+  }
+  return filesProcessed;
+}
+
+int get_file_size(const char* filename)
+{
+  FILE *inFile;
+  int file_size = -1;
+  inFile = fopen(filename, "rb");
+  if (inFile == NULL) {
+    printf("Failed to open file \"%s\"\n", filename);
+    exit(-1);
+  }
+  fseek(inFile, 0, SEEK_END);
+  file_size = ftell(inFile);
+  fclose(inFile);
+  return file_size;
+}
+
+void process_file_data(const char *filename, FILE *data_file)
+{
+  FILE *source_file;
+  size_t len, written, i, src_off=0;
+
+  source_file = fopen(filename, "rb");
+
+  do {
+    size_t off = 0;
+    len = fread(file_buffer_raw, 1, COPY_BUFSIZE, source_file);
+    if (len > 0) {
+      for (i = 0; i < len; i++) {
+        sprintf(&file_buffer_c[off], "0x%02.2x,", file_buffer_raw[i]);
+        off += 5;
+        if ((++src_off % HEX_BYTES_PER_LINE) == 0) {
+          memcpy(&file_buffer_c[off], NEWLINE, NEWLINE_LEN);
+          off += NEWLINE_LEN;
+        }
+      }
+      written = fwrite(file_buffer_c, 1, off, data_file);
+    }
+  } while(len > 0);
+  fclose(source_file);
+}
+
+int write_checksums(FILE *struct_file, const char *filename, const char *varname,
+                    u16_t hdr_len, u16_t hdr_chksum)
+{
+  int chunk_size = TCP_MSS;
+  int offset;
+  size_t len;
+  int i = 0;
+  FILE *f;
+#if LWIP_TCP_TIMESTAMPS
+  /* when timestamps are used, usable space is 12 bytes less per segment */
+  chunk_size -= 12;
+#endif
+
+  fprintf(struct_file, "#if HTTPD_PRECALCULATED_CHECKSUM" NEWLINE);
+  fprintf(struct_file, "const struct fsdata_chksum chksums_%s[] = {" NEWLINE, varname);
+
+  memset(file_buffer_raw, 0xab, sizeof(file_buffer_raw));
+  f = fopen(filename, "rb");
+  if (f == INVALID_HANDLE_VALUE) {
+    printf("Failed to open file \"%s\"\n", filename);
+    exit(-1);
+  }
+  if (hdr_len > 0) {
+    /* add checksum for HTTP header */
+    fprintf(struct_file, "{%d, 0x%04x, %d}," NEWLINE, 0, hdr_chksum, hdr_len);
+    i++;
+  }
+  for (offset = hdr_len; ; offset += len) {
+    unsigned short chksum;
+    len = fread(file_buffer_raw, 1, chunk_size, f);
+    if (len == 0) {
+      break;
+    }
+    chksum = ~inet_chksum(file_buffer_raw, (u16_t)len);
+    /* add checksum for data */
+    fprintf(struct_file, "{%d, 0x%04x, %d}," NEWLINE, offset, chksum, len);
+    i++;
+  }
+  fclose(f);
+  fprintf(struct_file, "};" NEWLINE);
+  fprintf(struct_file, "#endif /* HTTPD_PRECALCULATED_CHECKSUM */" NEWLINE);
+  return i;
+}
+
+int process_file(FILE *data_file, FILE *struct_file, const char *filename)
+{
+  char *pch;
+  char varname[MAX_PATH_LEN];
+  int i = 0;
+  char qualifiedName[MAX_PATH_LEN];
+  int file_size;
+  u16_t http_hdr_chksum = 0;
+  u16_t http_hdr_len = 0;
+  int chksum_count = 0;
+
+  /* create qualified name (TODO: prepend slash or not?) */
+  sprintf(qualifiedName,"%s/%s", curSubdir, filename);
+  /* create C variable name */
+  strcpy(varname, qualifiedName);
+  /* convert slashes & dots to underscores */
+  while ((pch = strpbrk(varname, "./\\")) != NULL) {
+    *pch = '_';
+  }
+#if ALIGN_PAYLOAD
+  /* to force even alignment of array */
+  fprintf(data_file, "static const " PAYLOAD_ALIGN_TYPE " dummy_align_%s = %d;" NEWLINE, varname, payload_alingment_dummy_counter++);
+#endif /* ALIGN_PAYLOAD */
+  fprintf(data_file, "static const unsigned char data_%s[] = {" NEWLINE, varname);
+  /* encode source file name (used by file system, not returned to browser) */
+  fprintf(data_file, "/* %s (%d chars) */" NEWLINE, qualifiedName, strlen(qualifiedName)+1);
+  file_put_ascii(data_file, qualifiedName, strlen(qualifiedName)+1, &i);
+#if ALIGN_PAYLOAD
+  /* pad to even number of bytes to assure payload is on aligned boundary */
+  while(i % PAYLOAD_ALIGNMENT != 0) {
+    fprintf(data_file, "0x%02.2x,", 0);
+    i++;
+  }
+#endif /* ALIGN_PAYLOAD */
+  fprintf(data_file, NEWLINE);
+
+  file_size = get_file_size(filename);
+  if (includeHttpHeader) {
+    file_write_http_header(data_file, filename, file_size, &http_hdr_len, &http_hdr_chksum);
+  }
+  if (precalcChksum) {
+    chksum_count = write_checksums(struct_file, filename, varname, http_hdr_len, http_hdr_chksum);
+  }
+
+  /* build declaration of struct fsdata_file in temp file */
+  fprintf(struct_file, "const struct fsdata_file file_%s[] = { {" NEWLINE, varname);
+  fprintf(struct_file, "file_%s," NEWLINE, lastFileVar);
+  fprintf(struct_file, "data_%s," NEWLINE, varname);
+  fprintf(struct_file, "data_%s + %d," NEWLINE, varname, i);
+  fprintf(struct_file, "sizeof(data_%s) - %d," NEWLINE, varname, i);
+  fprintf(struct_file, "%d," NEWLINE, includeHttpHeader);
+  if (precalcChksum) {
+    fprintf(struct_file, "#if HTTPD_PRECALCULATED_CHECKSUM" NEWLINE);
+    fprintf(struct_file, "%d, chksums_%s," NEWLINE, chksum_count, varname);
+    fprintf(struct_file, "#endif /* HTTPD_PRECALCULATED_CHECKSUM */" NEWLINE);
+  }
+  fprintf(struct_file, "}};" NEWLINE NEWLINE);
+  strcpy(lastFileVar, varname);
+
+  /* write actual file contents */
+  i = 0;
+  fprintf(data_file, NEWLINE "/* raw file data (%d bytes) */" NEWLINE, file_size);
+  process_file_data(filename, data_file);
+  fprintf(data_file, "};" NEWLINE NEWLINE);
+
+  return 0;
+}
+
+int file_write_http_header(FILE *data_file, const char *filename, int file_size,
+                           u16_t *http_hdr_len, u16_t *http_hdr_chksum)
+{
+  int i = 0;
+  int response_type = HTTP_HDR_OK;
+  int file_type = HTTP_HDR_DEFAULT_TYPE;
+  const char *cur_string;
+  size_t cur_len;
+  int written = 0;
+  size_t hdr_len = 0;
+  u16_t acc;
+  const char *file_ext;
+  int j;
+  u8_t keepalive = useHttp11;
+
+  if (keepalive) {
+    size_t loop;
+    for (loop = 0; loop < NUM_SHTML_EXTENSIONS; loop++) {
+      if (strstr(filename, g_pcSSIExtensions[loop])) {
+        /* no keepalive connection for SSI files */
+        keepalive = 0;
+      }
+    }
+  }
+
+  memset(hdr_buf, 0, sizeof(hdr_buf));
+  
+  if (useHttp11) {
+    response_type = HTTP_HDR_OK_11;
+  }
+
+  fprintf(data_file, NEWLINE "/* HTTP header */");
+  if (strstr(filename, "404") == filename) {
+    response_type = HTTP_HDR_NOT_FOUND;
+    if (useHttp11) {
+      response_type = HTTP_HDR_NOT_FOUND_11;
+    }
+  } else if (strstr(filename, "400") == filename) {
+    response_type = HTTP_HDR_BAD_REQUEST;
+    if (useHttp11) {
+      response_type = HTTP_HDR_BAD_REQUEST_11;
+    }
+  } else if (strstr(filename, "501") == filename) {
+    response_type = HTTP_HDR_NOT_IMPL;
+    if (useHttp11) {
+      response_type = HTTP_HDR_NOT_IMPL_11;
+    }
+  }
+  cur_string = g_psHTTPHeaderStrings[response_type];
+  cur_len = strlen(cur_string);
+  fprintf(data_file, NEWLINE "/* \"%s\" (%d bytes) */" NEWLINE, cur_string, cur_len);
+  written += file_put_ascii(data_file, cur_string, cur_len, &i);
+  i = 0;
+  if (precalcChksum) {
+    memcpy(&hdr_buf[hdr_len], cur_string, cur_len);
+    hdr_len += cur_len;
+  }
+
+  cur_string = serverID;
+  cur_len = strlen(cur_string);
+  fprintf(data_file, NEWLINE "/* \"%s\" (%d bytes) */" NEWLINE, cur_string, cur_len);
+  written += file_put_ascii(data_file, cur_string, cur_len, &i);
+  i = 0;
+  if (precalcChksum) {
+    memcpy(&hdr_buf[hdr_len], cur_string, cur_len);
+    hdr_len += cur_len;
+  }
+
+  file_ext = filename;
+  while(strstr(file_ext, ".") != NULL) {
+    file_ext = strstr(file_ext, ".");
+    file_ext++;
+  }
+  if((file_ext == NULL) || (*file_ext == 0)) {
+    printf("failed to get extension for file \"%s\", using default.\n", filename);
+  } else {
+    for(j = 0; j < NUM_HTTP_HEADERS; j++) {
+      if(!strcmp(file_ext, g_psHTTPHeaders[j].extension)) {
+        file_type = g_psHTTPHeaders[j].headerIndex;
+        break;
+      }
+    }
+    if (j >= NUM_HTTP_HEADERS) {
+      printf("failed to get file type for extension \"%s\", using default.\n", file_ext);
+      file_type = HTTP_HDR_DEFAULT_TYPE;
+    }
+  }
+
+  if (useHttp11) {
+    char intbuf[MAX_PATH_LEN];
+    int content_len = file_size;
+    memset(intbuf, 0, sizeof(intbuf));
+
+    if (!keepalive) {
+      content_len *= 2;
+    }
+    {
+      cur_string = g_psHTTPHeaderStrings[HTTP_HDR_CONTENT_LENGTH];
+      cur_len = strlen(cur_string);
+      fprintf(data_file, NEWLINE "/* \"%s%d\r\n\" (%d+ bytes) */" NEWLINE, cur_string, content_len, cur_len+2);
+      written += file_put_ascii(data_file, cur_string, cur_len, &i);
+      if (precalcChksum) {
+        memcpy(&hdr_buf[hdr_len], cur_string, cur_len);
+        hdr_len += cur_len;
+      }
+
+      _itoa(content_len, intbuf, 10);
+      strcat(intbuf, "\r\n");
+      cur_len = strlen(intbuf);
+      written += file_put_ascii(data_file, intbuf, cur_len, &i);
+      i = 0;
+      if (precalcChksum) {
+        memcpy(&hdr_buf[hdr_len], intbuf, cur_len);
+        hdr_len += cur_len;
+      }
+    }
+
+    if (keepalive) {
+      cur_string = g_psHTTPHeaderStrings[HTTP_HDR_CONN_KEEPALIVE];
+    } else {
+      cur_string = g_psHTTPHeaderStrings[HTTP_HDR_CONN_CLOSE];
+    }
+    cur_len = strlen(cur_string);
+    fprintf(data_file, NEWLINE "/* \"%s\" (%d bytes) */" NEWLINE, cur_string, cur_len);
+    written += file_put_ascii(data_file, cur_string, cur_len, &i);
+    i = 0;
+    if (precalcChksum) {
+      memcpy(&hdr_buf[hdr_len], cur_string, cur_len);
+      hdr_len += cur_len;
+    }
+  }
+
+  cur_string = g_psHTTPHeaderStrings[file_type];
+  cur_len = strlen(cur_string);
+  fprintf(data_file, NEWLINE "/* \"%s\" (%d bytes) */" NEWLINE, cur_string, cur_len);
+  written += file_put_ascii(data_file, cur_string, cur_len, &i);
+  i = 0;
+  if (precalcChksum) {
+    memcpy(&hdr_buf[hdr_len], cur_string, cur_len);
+    hdr_len += cur_len;
+
+    LWIP_ASSERT("hdr_len <= 0xffff", hdr_len <= 0xffff);
+    LWIP_ASSERT("strlen(hdr_buf) == hdr_len", strlen(hdr_buf) == hdr_len);
+    acc = ~inet_chksum(hdr_buf, (u16_t)hdr_len);
+    *http_hdr_len = (u16_t)hdr_len;
+    *http_hdr_chksum = acc;
+  }
+
+  return written;
+}
+
+int file_put_ascii(FILE *file, const char* ascii_string, int len, int *i)
+{
+  int x;
+  for(x = 0; x < len; x++) {
+    unsigned char cur = ascii_string[x];
+    fprintf(file, "0x%02.2x,", cur);
+    if ((++(*i) % HEX_BYTES_PER_LINE) == 0) {
+      fprintf(file, NEWLINE);
+    }
+  }
+  return len;
+}
+
+int s_put_ascii(char *buf, const char *ascii_string, int len, int *i)
+{
+  int x;
+  int idx = 0;
+  for(x = 0; x < len; x++) {
+    unsigned char cur = ascii_string[x];
+    sprintf(&buf[idx], "0x%02.2x,", cur);
+    idx += 5;
+    if ((++(*i) % HEX_BYTES_PER_LINE) == 0) {
+      sprintf(&buf[idx], NEWLINE);
+      idx += NEWLINE_LEN;
+    }
+  }
+  return len;
+}

src/lwip-1.4.1/apps/httpserver_raw/makefsdata/readme.txt

@@ -0,0 +1,13 @@
+This directory contains a script ('makefsdata') to create C code suitable for
+httpd for given html pages (or other files) in a directory.
+
+There is also a plain C console application doing the same and extended a bit.
+
+Usage: htmlgen [targetdir] [-s] [-i]s
+   targetdir: relative or absolute path to files to convert
+   switch -s: toggle processing of subdirectories (default is on)
+   switch -e: exclude HTTP header from file (header is created at runtime, default is on)
+   switch -11: include HTTP 1.1 header (1.0 is default)
+
+  if targetdir not specified, makefsdata will attempt to
+  process files in subdirectory 'fs'.

src/lwip-1.4.1/apps/netbios/netbios.c

@@ -0,0 +1,337 @@
+/**
+ * @file
+ * NetBIOS name service sample
+ *
+ */
+
+/*
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_UDP  /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/udp.h"
+#include "lwip/netif.h"
+
+#include <string.h>
+
+/** This is an example implementation of a NetBIOS name server.
+ * It responds to name queries for a configurable name.
+ * Name resolving is not supported.
+ *
+ * Note that the device doesn't broadcast it's own name so can't
+ * detect duplicate names!
+ */
+
+/** NetBIOS name of LWIP device
+ * This must be uppercase until NETBIOS_STRCMP() is defined to a string
+ * comparision function that is case insensitive.
+ * If you want to use the netif's hostname, use this (with LWIP_NETIF_HOSTNAME):
+ * (ip_current_netif() != NULL ? ip_current_netif()->hostname != NULL ? ip_current_netif()->hostname : "" : "")
+ */
+#ifndef NETBIOS_LWIP_NAME
+#define NETBIOS_LWIP_NAME "NETBIOSLWIPDEV"
+#endif
+
+/** Since there's no standard function for case-insensitive string comparision,
+ * we need another define here:
+ * define this to stricmp() for windows or strcasecmp() for linux.
+ * If not defined, comparision is case sensitive and NETBIOS_LWIP_NAME must be
+ * uppercase
+ */
+#ifndef NETBIOS_STRCMP
+#define NETBIOS_STRCMP(str1, str2) strcmp(str1, str2)
+#endif
+
+/** default port number for "NetBIOS Name service */
+#define NETBIOS_PORT     137
+
+/** size of a NetBIOS name */
+#define NETBIOS_NAME_LEN 16
+
+/** The Time-To-Live for NetBIOS name responds (in seconds)
+ * Default is 300000 seconds (3 days, 11 hours, 20 minutes) */
+#define NETBIOS_NAME_TTL 300000
+
+/** NetBIOS header flags */
+#define NETB_HFLAG_RESPONSE           0x8000U
+#define NETB_HFLAG_OPCODE             0x7800U
+#define NETB_HFLAG_OPCODE_NAME_QUERY  0x0000U
+#define NETB_HFLAG_AUTHORATIVE        0x0400U
+#define NETB_HFLAG_TRUNCATED          0x0200U
+#define NETB_HFLAG_RECURS_DESIRED     0x0100U
+#define NETB_HFLAG_RECURS_AVAILABLE   0x0080U
+#define NETB_HFLAG_BROADCAST          0x0010U
+#define NETB_HFLAG_REPLYCODE          0x0008U
+#define NETB_HFLAG_REPLYCODE_NOERROR  0x0000U
+
+/** NetBIOS name flags */
+#define NETB_NFLAG_UNIQUE             0x8000U
+#define NETB_NFLAG_NODETYPE           0x6000U
+#define NETB_NFLAG_NODETYPE_HNODE     0x6000U
+#define NETB_NFLAG_NODETYPE_MNODE     0x4000U
+#define NETB_NFLAG_NODETYPE_PNODE     0x2000U
+#define NETB_NFLAG_NODETYPE_BNODE     0x0000U
+
+/** NetBIOS message header */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct netbios_hdr {
+  PACK_STRUCT_FIELD(u16_t trans_id);
+  PACK_STRUCT_FIELD(u16_t flags);
+  PACK_STRUCT_FIELD(u16_t questions);
+  PACK_STRUCT_FIELD(u16_t answerRRs);
+  PACK_STRUCT_FIELD(u16_t authorityRRs);
+  PACK_STRUCT_FIELD(u16_t additionalRRs);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+/** NetBIOS message name part */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct netbios_name_hdr {
+  PACK_STRUCT_FIELD(u8_t  nametype);
+  PACK_STRUCT_FIELD(u8_t  encname[(NETBIOS_NAME_LEN*2)+1]);
+  PACK_STRUCT_FIELD(u16_t type);
+  PACK_STRUCT_FIELD(u16_t cls);
+  PACK_STRUCT_FIELD(u32_t ttl);
+  PACK_STRUCT_FIELD(u16_t datalen);
+  PACK_STRUCT_FIELD(u16_t flags);
+  PACK_STRUCT_FIELD(ip_addr_p_t addr);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+/** NetBIOS message */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct netbios_resp
+{
+  struct netbios_hdr      resp_hdr;
+  struct netbios_name_hdr resp_name;
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+/** NetBIOS decoding name */
+static int
+netbios_name_decoding( char *name_enc, char *name_dec, int name_dec_len)
+{
+  char *pname;
+  char  cname;
+  char  cnbname;
+  int   index = 0;
+
+  LWIP_UNUSED_ARG(name_dec_len);
+
+  /* Start decoding netbios name. */
+  pname  = name_enc;
+  for (;;) {
+    /* Every two characters of the first level-encoded name
+     * turn into one character in the decoded name. */
+    cname = *pname;
+    if (cname == '\0')
+      break;    /* no more characters */
+    if (cname == '.')
+      break;    /* scope ID follows */
+    if (cname < 'A' || cname > 'Z') {
+      /* Not legal. */
+      return -1;
+    }
+    cname -= 'A';
+    cnbname = cname << 4;
+    pname++;
+
+    cname = *pname;
+    if (cname == '\0' || cname == '.') {
+      /* No more characters in the name - but we're in
+       * the middle of a pair.  Not legal. */
+      return -1;
+    }
+    if (cname < 'A' || cname > 'Z') {
+      /* Not legal. */
+      return -1;
+    }
+    cname -= 'A';
+    cnbname |= cname;
+    pname++;
+
+    /* Do we have room to store the character? */
+    if (index < NETBIOS_NAME_LEN) {
+      /* Yes - store the character. */
+      name_dec[index++] = (cnbname!=' '?cnbname:'\0');
+    }
+  }
+
+  return 0;
+}
+
+#if 0 /* function currently unused */
+/** NetBIOS encoding name */
+static int
+netbios_name_encoding(char *name_enc, char *name_dec, int name_dec_len)
+{
+  char         *pname;
+  char          cname;
+  unsigned char ucname;
+  int           index = 0;
+  
+  /* Start encoding netbios name. */
+  pname = name_enc;
+
+  for (;;) {
+    /* Every two characters of the first level-encoded name
+     * turn into one character in the decoded name. */
+    cname = *pname;
+    if (cname == '\0')
+      break;    /* no more characters */
+    if (cname == '.')
+      break;    /* scope ID follows */
+    if ((cname < 'A' || cname > 'Z') && (cname < '0' || cname > '9')) {
+      /* Not legal. */
+      return -1;
+    }
+
+    /* Do we have room to store the character? */
+    if (index >= name_dec_len) {
+      return -1;
+    }
+
+    /* Yes - store the character. */
+    ucname = cname;
+    name_dec[index++] = ('A'+((ucname>>4) & 0x0F));
+    name_dec[index++] = ('A'+( ucname     & 0x0F));
+    pname++;
+  }
+
+  /* Fill with "space" coding */
+  for (;index<name_dec_len-1;) {
+    name_dec[index++] = 'C';
+    name_dec[index++] = 'A';
+  }
+
+  /* Terminate string */
+  name_dec[index]='\0';
+
+  return 0;
+}
+#endif /* 0 */
+
+/** NetBIOS Name service recv callback */
+static void
+netbios_recv(void *arg, struct udp_pcb *upcb, struct pbuf *p, ip_addr_t *addr, u16_t port)
+{
+  LWIP_UNUSED_ARG(arg);
+
+  /* if packet is valid */
+  if (p != NULL) {
+    char   netbios_name[NETBIOS_NAME_LEN+1];
+    struct netbios_hdr*      netbios_hdr      = (struct netbios_hdr*)p->payload;
+    struct netbios_name_hdr* netbios_name_hdr = (struct netbios_name_hdr*)(netbios_hdr+1);
+    
+    /* we only answer if we got a default interface */
+    if (netif_default != NULL) {
+      /* @todo: do we need to check answerRRs/authorityRRs/additionalRRs? */
+      /* if the packet is a NetBIOS name query question */
+      if (((netbios_hdr->flags & PP_NTOHS(NETB_HFLAG_OPCODE)) == PP_NTOHS(NETB_HFLAG_OPCODE_NAME_QUERY)) &&
+          ((netbios_hdr->flags & PP_NTOHS(NETB_HFLAG_RESPONSE)) == 0) &&
+           (netbios_hdr->questions == PP_NTOHS(1))) {
+        /* decode the NetBIOS name */
+        netbios_name_decoding( (char*)(netbios_name_hdr->encname), netbios_name, sizeof(netbios_name));
+        /* if the packet is for us */
+        if (NETBIOS_STRCMP(netbios_name, NETBIOS_LWIP_NAME) == 0) {
+          struct pbuf *q;
+          struct netbios_resp *resp;
+
+          q = pbuf_alloc(PBUF_TRANSPORT, sizeof(struct netbios_resp), PBUF_RAM);
+          if (q != NULL) {
+            resp = (struct netbios_resp*)q->payload;
+
+            /* prepare NetBIOS header response */
+            resp->resp_hdr.trans_id      = netbios_hdr->trans_id;
+            resp->resp_hdr.flags         = PP_HTONS(NETB_HFLAG_RESPONSE |
+                                                 NETB_HFLAG_OPCODE_NAME_QUERY |
+                                                 NETB_HFLAG_AUTHORATIVE |
+                                                 NETB_HFLAG_RECURS_DESIRED);
+            resp->resp_hdr.questions     = 0;
+            resp->resp_hdr.answerRRs     = PP_HTONS(1);
+            resp->resp_hdr.authorityRRs  = 0;
+            resp->resp_hdr.additionalRRs = 0;
+
+            /* prepare NetBIOS header datas */
+            MEMCPY( resp->resp_name.encname, netbios_name_hdr->encname, sizeof(netbios_name_hdr->encname));
+            resp->resp_name.nametype     = netbios_name_hdr->nametype;
+            resp->resp_name.type         = netbios_name_hdr->type;
+            resp->resp_name.cls          = netbios_name_hdr->cls;
+            resp->resp_name.ttl          = PP_HTONL(NETBIOS_NAME_TTL);
+            resp->resp_name.datalen      = PP_HTONS(sizeof(resp->resp_name.flags)+sizeof(resp->resp_name.addr));
+            resp->resp_name.flags        = PP_HTONS(NETB_NFLAG_NODETYPE_BNODE);
+            ip_addr_copy(resp->resp_name.addr, netif_default->ip_addr);
+
+            /* send the NetBIOS response */
+            udp_sendto(upcb, q, addr, port);
+            
+            /* free the "reference" pbuf */
+            pbuf_free(q);
+          }
+        }
+      }
+    }
+    /* free the pbuf */
+    pbuf_free(p);
+  }
+}
+
+void netbios_init(void)
+{
+  struct udp_pcb *pcb;
+
+  LWIP_ASSERT("NetBIOS name is too long!", strlen(NETBIOS_LWIP_NAME) < NETBIOS_NAME_LEN);
+
+  pcb = udp_new();
+  if (pcb != NULL) {
+    /* we have to be allowed to send broadcast packets! */
+    pcb->so_options |= SOF_BROADCAST;
+    udp_bind(pcb, IP_ADDR_ANY, NETBIOS_PORT);
+    udp_recv(pcb, netbios_recv, pcb);
+  }
+}
+#endif /* LWIP_UDP */

src/lwip-1.4.1/apps/netbios/netbios.h

@@ -0,0 +1,6 @@
+#ifndef __NETBIOS_H__
+#define __NETBIOS_H__
+
+void netbios_init(void);
+
+#endif /* __NETBIOS_H__ */

src/lwip-1.4.1/apps/netio/netio.c

@@ -0,0 +1,51 @@
+#include "netio.h"
+
+#include "lwip/opt.h"
+#include "lwip/tcp.h"
+
+/* See http://www.nwlab.net/art/netio/netio.html to get the netio tool */
+
+#if LWIP_TCP
+static err_t netio_recv(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
+{
+
+  LWIP_UNUSED_ARG(arg);
+
+  if (err == ERR_OK && p != NULL) {
+    tcp_recved(pcb, p->tot_len);
+    pbuf_free(p);
+  } else {
+    pbuf_free(p);
+  }
+
+  if (err == ERR_OK && p == NULL) {
+    tcp_arg(pcb, NULL);
+    tcp_sent(pcb, NULL);
+    tcp_recv(pcb, NULL);
+    tcp_close(pcb);
+  }
+
+  return ERR_OK;
+}
+
+static err_t netio_accept(void *arg, struct tcp_pcb *pcb, err_t err)
+{
+  LWIP_UNUSED_ARG(arg);
+  LWIP_UNUSED_ARG(err);
+
+  tcp_arg(pcb, NULL);
+  tcp_sent(pcb, NULL);
+  tcp_recv(pcb, netio_recv);
+  return ERR_OK;
+}
+
+void netio_init(void)
+{
+  struct tcp_pcb *pcb;
+
+  pcb = tcp_new();
+  tcp_bind(pcb, IP_ADDR_ANY, 18767);
+  pcb = tcp_listen(pcb);
+  tcp_accept(pcb, netio_accept);
+}
+#endif /* LWIP_TCP */

src/lwip-1.4.1/apps/netio/netio.h

@@ -0,0 +1,6 @@
+#ifndef __NETIO_H__
+#define __NETIO_H__
+
+void netio_init(void);
+
+#endif /* __NETIO_H__ */

src/lwip-1.4.1/apps/ping/ping.c

@@ -0,0 +1,329 @@
+/**
+ * @file
+ * Ping sender module
+ *
+ */
+
+/*
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ */
+
+/** 
+ * This is an example of a "ping" sender (with raw API and socket API).
+ * It can be used as a start point to maintain opened a network connection, or
+ * like a network "watchdog" for your device.
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_RAW /* don't build if not configured for use in lwipopts.h */
+
+#include "ping.h"
+
+#include "lwip/mem.h"
+#include "lwip/raw.h"
+#include "lwip/icmp.h"
+#include "lwip/netif.h"
+#include "lwip/sys.h"
+#include "lwip/timers.h"
+#include "lwip/inet_chksum.h"
+
+#if PING_USE_SOCKETS
+#include "lwip/sockets.h"
+#include "lwip/inet.h"
+#endif /* PING_USE_SOCKETS */
+
+
+/**
+ * PING_DEBUG: Enable debugging for PING.
+ */
+#ifndef PING_DEBUG
+#define PING_DEBUG     LWIP_DBG_ON
+#endif
+
+/** ping target - should be a "ip_addr_t" */
+#ifndef PING_TARGET
+#define PING_TARGET   (netif_default?netif_default->gw:ip_addr_any)
+#endif
+
+/** ping receive timeout - in milliseconds */
+#ifndef PING_RCV_TIMEO
+#define PING_RCV_TIMEO 1000
+#endif
+
+/** ping delay - in milliseconds */
+#ifndef PING_DELAY
+#define PING_DELAY     1000
+#endif
+
+/** ping identifier - must fit on a u16_t */
+#ifndef PING_ID
+#define PING_ID        0xAFAF
+#endif
+
+/** ping additional data size to include in the packet */
+#ifndef PING_DATA_SIZE
+#define PING_DATA_SIZE 32
+#endif
+
+/** ping result action - no default action */
+#ifndef PING_RESULT
+#define PING_RESULT(ping_ok)
+#endif
+
+/* ping variables */
+static u16_t ping_seq_num;
+static u32_t ping_time;
+#if !PING_USE_SOCKETS
+static struct raw_pcb *ping_pcb;
+#endif /* PING_USE_SOCKETS */
+
+/** Prepare a echo ICMP request */
+static void
+ping_prepare_echo( struct icmp_echo_hdr *iecho, u16_t len)
+{
+  size_t i;
+  size_t data_len = len - sizeof(struct icmp_echo_hdr);
+
+  ICMPH_TYPE_SET(iecho, ICMP_ECHO);
+  ICMPH_CODE_SET(iecho, 0);
+  iecho->chksum = 0;
+  iecho->id     = PING_ID;
+  iecho->seqno  = htons(++ping_seq_num);
+
+  /* fill the additional data buffer with some data */
+  for(i = 0; i < data_len; i++) {
+    ((char*)iecho)[sizeof(struct icmp_echo_hdr) + i] = (char)i;
+  }
+
+  iecho->chksum = inet_chksum(iecho, len);
+}
+
+#if PING_USE_SOCKETS
+
+/* Ping using the socket ip */
+static err_t
+ping_send(int s, ip_addr_t *addr)
+{
+  int err;
+  struct icmp_echo_hdr *iecho;
+  struct sockaddr_in to;
+  size_t ping_size = sizeof(struct icmp_echo_hdr) + PING_DATA_SIZE;
+  LWIP_ASSERT("ping_size is too big", ping_size <= 0xffff);
+
+  iecho = (struct icmp_echo_hdr *)mem_malloc((mem_size_t)ping_size);
+  if (!iecho) {
+    return ERR_MEM;
+  }
+
+  ping_prepare_echo(iecho, (u16_t)ping_size);
+
+  to.sin_len = sizeof(to);
+  to.sin_family = AF_INET;
+  inet_addr_from_ipaddr(&to.sin_addr, addr);
+
+  err = lwip_sendto(s, iecho, ping_size, 0, (struct sockaddr*)&to, sizeof(to));
+
+  mem_free(iecho);
+
+  return (err ? ERR_OK : ERR_VAL);
+}
+
+static void
+ping_recv(int s)
+{
+  char buf[64];
+  int fromlen, len;
+  struct sockaddr_in from;
+  struct ip_hdr *iphdr;
+  struct icmp_echo_hdr *iecho;
+
+  while((len = lwip_recvfrom(s, buf, sizeof(buf), 0, (struct sockaddr*)&from, (socklen_t*)&fromlen)) > 0) {
+    if (len >= (int)(sizeof(struct ip_hdr)+sizeof(struct icmp_echo_hdr))) {
+      ip_addr_t fromaddr;
+      inet_addr_to_ipaddr(&fromaddr, &from.sin_addr);
+      LWIP_DEBUGF( PING_DEBUG, ("ping: recv "));
+      ip_addr_debug_print(PING_DEBUG, &fromaddr);
+      LWIP_DEBUGF( PING_DEBUG, (" %"U32_F" ms\n", (sys_now() - ping_time)));
+
+      iphdr = (struct ip_hdr *)buf;
+      iecho = (struct icmp_echo_hdr *)(buf + (IPH_HL(iphdr) * 4));
+      if ((iecho->id == PING_ID) && (iecho->seqno == htons(ping_seq_num))) {
+        /* do some ping result processing */
+        PING_RESULT((ICMPH_TYPE(iecho) == ICMP_ER));
+        return;
+      } else {
+        LWIP_DEBUGF( PING_DEBUG, ("ping: drop\n"));
+      }
+    }
+  }
+
+  if (len == 0) {
+    LWIP_DEBUGF( PING_DEBUG, ("ping: recv - %"U32_F" ms - timeout\n", (sys_now()-ping_time)));
+  }
+
+  /* do some ping result processing */
+  PING_RESULT(0);
+}
+
+static void
+ping_thread(void *arg)
+{
+  int s;
+  int timeout = PING_RCV_TIMEO;
+  ip_addr_t ping_target;
+
+  LWIP_UNUSED_ARG(arg);
+
+  if ((s = lwip_socket(AF_INET, SOCK_RAW, IP_PROTO_ICMP)) < 0) {
+    return;
+  }
+
+  lwip_setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, &timeout, sizeof(timeout));
+
+  while (1) {
+    ping_target = PING_TARGET;
+
+    if (ping_send(s, &ping_target) == ERR_OK) {
+      LWIP_DEBUGF( PING_DEBUG, ("ping: send "));
+      ip_addr_debug_print(PING_DEBUG, &ping_target);
+      LWIP_DEBUGF( PING_DEBUG, ("\n"));
+
+      ping_time = sys_now();
+      ping_recv(s);
+    } else {
+      LWIP_DEBUGF( PING_DEBUG, ("ping: send "));
+      ip_addr_debug_print(PING_DEBUG, &ping_target);
+      LWIP_DEBUGF( PING_DEBUG, (" - error\n"));
+    }
+    sys_msleep(PING_DELAY);
+  }
+}
+
+#else /* PING_USE_SOCKETS */
+
+/* Ping using the raw ip */
+static u8_t
+ping_recv(void *arg, struct raw_pcb *pcb, struct pbuf *p, ip_addr_t *addr)
+{
+  struct icmp_echo_hdr *iecho;
+  LWIP_UNUSED_ARG(arg);
+  LWIP_UNUSED_ARG(pcb);
+  LWIP_UNUSED_ARG(addr);
+  LWIP_ASSERT("p != NULL", p != NULL);
+
+  if ((p->tot_len >= (PBUF_IP_HLEN + sizeof(struct icmp_echo_hdr))) &&
+      pbuf_header( p, -PBUF_IP_HLEN) == 0) {
+    iecho = (struct icmp_echo_hdr *)p->payload;
+
+    if ((iecho->id == PING_ID) && (iecho->seqno == htons(ping_seq_num))) {
+      LWIP_DEBUGF( PING_DEBUG, ("ping: recv "));
+      ip_addr_debug_print(PING_DEBUG, addr);
+      LWIP_DEBUGF( PING_DEBUG, (" %"U32_F" ms\n", (sys_now()-ping_time)));
+
+      /* do some ping result processing */
+      PING_RESULT(1);
+      pbuf_free(p);
+      return 1; /* eat the packet */
+    }
+  }
+
+  return 0; /* don't eat the packet */
+}
+
+static void
+ping_send(struct raw_pcb *raw, ip_addr_t *addr)
+{
+  struct pbuf *p;
+  struct icmp_echo_hdr *iecho;
+  size_t ping_size = sizeof(struct icmp_echo_hdr) + PING_DATA_SIZE;
+
+  LWIP_DEBUGF( PING_DEBUG, ("ping: send "));
+  ip_addr_debug_print(PING_DEBUG, addr);
+  LWIP_DEBUGF( PING_DEBUG, ("\n"));
+  LWIP_ASSERT("ping_size <= 0xffff", ping_size <= 0xffff);
+
+  p = pbuf_alloc(PBUF_IP, (u16_t)ping_size, PBUF_RAM);
+  if (!p) {
+    return;
+  }
+  if ((p->len == p->tot_len) && (p->next == NULL)) {
+    iecho = (struct icmp_echo_hdr *)p->payload;
+
+    ping_prepare_echo(iecho, (u16_t)ping_size);
+
+    raw_sendto(raw, p, addr);
+    ping_time = sys_now();
+  }
+  pbuf_free(p);
+}
+
+static void
+ping_timeout(void *arg)
+{
+  struct raw_pcb *pcb = (struct raw_pcb*)arg;
+  ip_addr_t ping_target = PING_TARGET;
+  
+  LWIP_ASSERT("ping_timeout: no pcb given!", pcb != NULL);
+
+  ping_send(pcb, &ping_target);
+
+  sys_timeout(PING_DELAY, ping_timeout, pcb);
+}
+
+static void
+ping_raw_init(void)
+{
+  ping_pcb = raw_new(IP_PROTO_ICMP);
+  LWIP_ASSERT("ping_pcb != NULL", ping_pcb != NULL);
+
+  raw_recv(ping_pcb, ping_recv, NULL);
+  raw_bind(ping_pcb, IP_ADDR_ANY);
+  sys_timeout(PING_DELAY, ping_timeout, ping_pcb);
+}
+
+void
+ping_send_now()
+{
+  ip_addr_t ping_target = PING_TARGET;
+  LWIP_ASSERT("ping_pcb != NULL", ping_pcb != NULL);
+  ping_send(ping_pcb, &ping_target);
+}
+
+#endif /* PING_USE_SOCKETS */
+
+void
+ping_init(void)
+{
+#if PING_USE_SOCKETS
+  sys_thread_new("ping_thread", ping_thread, NULL, DEFAULT_THREAD_STACKSIZE, DEFAULT_THREAD_PRIO);
+#else /* PING_USE_SOCKETS */
+  ping_raw_init();
+#endif /* PING_USE_SOCKETS */
+}
+
+#endif /* LWIP_RAW */

src/lwip-1.4.1/apps/ping/ping.h

@@ -0,0 +1,18 @@
+#ifndef __PING_H__
+#define __PING_H__
+
+/**
+ * PING_USE_SOCKETS: Set to 1 to use sockets, otherwise the raw api is used
+ */
+#ifndef PING_USE_SOCKETS
+#define PING_USE_SOCKETS    LWIP_SOCKET
+#endif
+
+
+void ping_init(void);
+
+#if !PING_USE_SOCKETS
+void ping_send_now(void);
+#endif /* !PING_USE_SOCKETS */
+
+#endif /* __PING_H__ */

src/lwip-1.4.1/apps/rtp/rtp.c

@@ -0,0 +1,294 @@
+/**
+ * @file
+ * RTP client/server module
+ *
+ */
+
+/*
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_SOCKET && LWIP_IGMP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/sys.h"
+#include "lwip/sockets.h"
+
+#include "rtpdata.h"
+
+#include <string.h>
+
+/** This is an example of a "RTP" client/server based on a MPEG4 bitstream (with socket API).
+ */
+
+/**
+ * RTP_DEBUG: Enable debugging for RTP.
+ */
+#ifndef RTP_DEBUG
+#define RTP_DEBUG                   LWIP_DBG_ON
+#endif
+
+/** RTP stream port */
+#ifndef RTP_STREAM_PORT
+#define RTP_STREAM_PORT             4000
+#endif
+
+/** RTP stream multicast address as IPv4 address in "u32_t" format */
+#ifndef RTP_STREAM_ADDRESS
+#define RTP_STREAM_ADDRESS          inet_addr("232.0.0.0")
+#endif
+
+/** RTP send delay - in milliseconds */
+#ifndef RTP_SEND_DELAY
+#define RTP_SEND_DELAY              40
+#endif
+
+/** RTP receive timeout - in milliseconds */
+#ifndef RTP_RECV_TIMEOUT
+#define RTP_RECV_TIMEOUT            2000
+#endif
+
+/** RTP stats display period - in received packets */
+#ifndef RTP_RECV_STATS
+#define RTP_RECV_STATS              50
+#endif
+
+/** RTP macro to let the application process the data */
+#ifndef RTP_RECV_PROCESSING
+#define RTP_RECV_PROCESSING(p,s)
+#endif
+
+/** RTP packet/payload size */
+#define RTP_PACKET_SIZE             1500
+#define RTP_PAYLOAD_SIZE            1024
+
+/** RTP header constants */
+#define RTP_VERSION                 0x80
+#define RTP_TIMESTAMP_INCREMENT     3600
+#define RTP_SSRC                    0
+#define RTP_PAYLOADTYPE             96
+#define RTP_MARKER_MASK             0x80
+
+/** RTP message header */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct rtp_hdr {
+  PACK_STRUCT_FIELD(u8_t  version);
+  PACK_STRUCT_FIELD(u8_t  payloadtype);
+  PACK_STRUCT_FIELD(u16_t seqNum);
+  PACK_STRUCT_FIELD(u32_t timestamp);
+  PACK_STRUCT_FIELD(u32_t ssrc);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+/** RTP packets */
+static u8_t rtp_send_packet[RTP_PACKET_SIZE];
+static u8_t rtp_recv_packet[RTP_PACKET_SIZE];
+
+/**
+ * RTP send packets
+ */
+static void
+rtp_send_packets( int sock, struct sockaddr_in* to)
+{
+  struct rtp_hdr* rtphdr;
+  u8_t*           rtp_payload;
+  int             rtp_payload_size;
+  int             rtp_data_index;
+
+  /* prepare RTP packet */
+  rtphdr = (struct rtp_hdr*)rtp_send_packet;
+  rtphdr->version     = RTP_VERSION;
+  rtphdr->payloadtype = 0;
+  rtphdr->ssrc        = PP_HTONL(RTP_SSRC);
+  rtphdr->timestamp   = htonl(ntohl(rtphdr->timestamp) + RTP_TIMESTAMP_INCREMENT);
+
+  /* send RTP stream packets */
+  rtp_data_index = 0;
+  do {
+    rtp_payload      = rtp_send_packet+sizeof(struct rtp_hdr);
+    rtp_payload_size = min(RTP_PAYLOAD_SIZE, (sizeof(rtp_data) - rtp_data_index));
+
+    memcpy(rtp_payload, rtp_data + rtp_data_index, rtp_payload_size);
+
+    /* set MARKER bit in RTP header on the last packet of an image */
+    rtphdr->payloadtype = RTP_PAYLOADTYPE | (((rtp_data_index + rtp_payload_size)
+      >= sizeof(rtp_data)) ? RTP_MARKER_MASK : 0);
+
+    /* send RTP stream packet */
+    if (sendto(sock, rtp_send_packet, sizeof(struct rtp_hdr) + rtp_payload_size,
+        0, (struct sockaddr *)to, sizeof(struct sockaddr)) >= 0) {
+      rtphdr->seqNum  = htons(ntohs(rtphdr->seqNum) + 1);
+      rtp_data_index += rtp_payload_size;
+    } else {
+      LWIP_DEBUGF(RTP_DEBUG, ("rtp_sender: not sendto==%i\n", errno));
+    }
+  }while (rtp_data_index < sizeof(rtp_data));
+}
+
+/**
+ * RTP send thread
+ */
+static void
+rtp_send_thread(void *arg)
+{
+  int                sock;
+  struct sockaddr_in local;
+  struct sockaddr_in to;
+  u32_t              rtp_stream_address;
+
+  LWIP_UNUSED_ARG(arg);
+
+  /* initialize RTP stream address */
+  rtp_stream_address = RTP_STREAM_ADDRESS;
+
+  /* if we got a valid RTP stream address... */
+  if (rtp_stream_address != 0) {
+    /* create new socket */
+    sock = socket(AF_INET, SOCK_DGRAM, 0);
+    if (sock >= 0) {
+      /* prepare local address */
+      memset(&local, 0, sizeof(local));
+      local.sin_family      = AF_INET;
+      local.sin_port        = PP_HTONS(INADDR_ANY);
+      local.sin_addr.s_addr = PP_HTONL(INADDR_ANY);
+
+      /* bind to local address */
+      if (bind(sock, (struct sockaddr *)&local, sizeof(local)) == 0) {
+        /* prepare RTP stream address */
+        memset(&to, 0, sizeof(to));
+        to.sin_family      = AF_INET;
+        to.sin_port        = PP_HTONS(RTP_STREAM_PORT);
+        to.sin_addr.s_addr = rtp_stream_address;
+
+        /* send RTP packets */
+        memset(rtp_send_packet, 0, sizeof(rtp_send_packet));
+        while (1) {
+          rtp_send_packets( sock, &to);
+          sys_msleep(RTP_SEND_DELAY);
+        }
+      }
+
+      /* close the socket */
+      closesocket(sock);
+    }
+  }
+}
+
+/**
+ * RTP recv thread
+ */
+static void
+rtp_recv_thread(void *arg)
+{
+  int                sock;
+  struct sockaddr_in local;
+  struct sockaddr_in from;
+  int                fromlen;
+  struct ip_mreq     ipmreq;
+  struct rtp_hdr*    rtphdr;
+  u32_t              rtp_stream_address;
+  int                timeout;
+  int                result;
+  int                recvrtppackets  = 0;
+  int                lostrtppackets  = 0;
+  u16_t              lastrtpseq = 0;
+
+  LWIP_UNUSED_ARG(arg);
+
+  /* initialize RTP stream address */
+  rtp_stream_address = RTP_STREAM_ADDRESS;
+
+  /* if we got a valid RTP stream address... */
+  if (rtp_stream_address != 0) {
+    /* create new socket */
+    sock = socket(AF_INET, SOCK_DGRAM, 0);
+    if (sock >= 0) {
+      /* prepare local address */
+      memset(&local, 0, sizeof(local));
+      local.sin_family      = AF_INET;
+      local.sin_port        = PP_HTONS(RTP_STREAM_PORT);
+      local.sin_addr.s_addr = PP_HTONL(INADDR_ANY);
+
+      /* bind to local address */
+      if (bind(sock, (struct sockaddr *)&local, sizeof(local)) == 0) {
+        /* set recv timeout */
+        timeout = RTP_RECV_TIMEOUT;
+        setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout, sizeof(timeout));
+
+        /* prepare multicast "ip_mreq" struct */
+        ipmreq.imr_multiaddr.s_addr = rtp_stream_address;
+        ipmreq.imr_interface.s_addr = PP_HTONL(INADDR_ANY);
+
+        /* join multicast group */
+        if (setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP, &ipmreq, sizeof(ipmreq)) == 0) {
+          /* receive RTP packets */
+          while(1) {
+            fromlen = sizeof(from);
+            result  = recvfrom(sock, rtp_recv_packet, sizeof(rtp_recv_packet), 0,
+              (struct sockaddr *)&from, (socklen_t *)&fromlen);
+            if (result >= sizeof(struct rtp_hdr)) {
+              rtphdr = (struct rtp_hdr *)rtp_recv_packet;
+              recvrtppackets++;
+              if ((lastrtpseq == 0) || ((lastrtpseq + 1) == ntohs(rtphdr->seqNum))) {
+                RTP_RECV_PROCESSING((rtp_recv_packet + sizeof(rtp_hdr)),(result-sizeof(rtp_hdr)));
+              } else {
+                lostrtppackets++;
+              }
+              lastrtpseq = ntohs(rtphdr->seqNum);
+              if ((recvrtppackets % RTP_RECV_STATS) == 0) {
+                LWIP_DEBUGF(RTP_DEBUG, ("rtp_recv_thread: recv %6i packet(s) / lost %4i packet(s) (%.4f%%)...\n", recvrtppackets, lostrtppackets, (lostrtppackets*100.0)/recvrtppackets));
+              }
+            } else {
+              LWIP_DEBUGF(RTP_DEBUG, ("rtp_recv_thread: recv timeout...\n"));
+            }
+          }
+
+          /* leave multicast group */
+          setsockopt(sock, IPPROTO_IP, IP_DROP_MEMBERSHIP, &ipmreq, sizeof(ipmreq));
+        }
+      }
+
+      /* close the socket */
+      closesocket(sock);
+    }
+  }
+}
+
+void
+rtp_init(void)
+{
+  sys_thread_new("rtp_send_thread", rtp_send_thread, NULL, DEFAULT_THREAD_STACKSIZE, DEFAULT_THREAD_PRIO);
+  sys_thread_new("rtp_recv_thread", rtp_recv_thread, NULL, DEFAULT_THREAD_STACKSIZE, DEFAULT_THREAD_PRIO);
+}
+
+#endif /* LWIP_SOCKET && LWIP_IGMP */

src/lwip-1.4.1/apps/rtp/rtp.h

@@ -0,0 +1,8 @@
+#ifndef __RTP_H__
+#define __RTP_H__
+
+#if LWIP_SOCKET && LWIP_IGMP
+void rtp_init(void);
+#endif /* LWIP_SOCKET && LWIP_IGMP */
+
+#endif /* __RTP_H__ */

src/lwip-1.4.1/apps/shell/shell.h

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __SHELL_H__
+#define __SHELL_H__
+
+void shell_init(void);
+
+#endif /* __SHELL_H__ */

src/lwip-1.4.1/apps/smtp/smtp.h

@@ -0,0 +1,67 @@
+#ifndef __SMTP_H__
+#define __SMTP_H__
+
+#include "lwip/err.h"
+
+/** The default TCP port used for SMTP */
+#define SMTP_DEFAULT_PORT  25
+
+/** Email successfully sent */
+#define SMTP_RESULT_OK            0
+/** Unknown error */
+#define SMTP_RESULT_ERR_UNKNOWN   1
+/** Connection to server failed */
+#define SMTP_RESULT_ERR_CONNECT   2
+/** Failed to resolve server hostname */
+#define SMTP_RESULT_ERR_HOSTNAME  3
+/** Connection unexpectedly closed by remote server */
+#define SMTP_RESULT_ERR_CLOSED    4
+/** Connection timed out (server didn't respond in time) */
+#define SMTP_RESULT_ERR_TIMEOUT   5
+/** Server responded with an unknown response code */
+#define SMTP_RESULT_ERR_SVR_RESP  6
+
+/** Prototype of an smtp callback function
+ *
+ * @param arg argument specified when initiating the email
+ * @param smtp_result result of the mail transfer (see defines SMTP_RESULT_*)
+ * @param srv_err if aborted by the server, this contains the error code received
+ * @param err an error returned by internal lwip functions, can help to specify
+ *            the source of the error but must not necessarily be != ERR_OK
+ */
+typedef void (*smtp_result_fn)(void *arg, u8_t smtp_result, u16_t srv_err, err_t err);
+
+/** This structure is used as argument for smtp_send_mail_int(),
+ * which in turn can be used with tcpip_callback() to send mail
+ * from interrupt context.
+ * For member description, see parameter description of smtp_send_mail().
+ * When using with tcpip_callback, this structure has to stay allocated
+ * (e.g. using mem_malloc/mem_free) until its 'callback_fn' is called.
+ */
+struct smtp_send_request {
+  const char *from;
+  const char* to;
+  const char* subject;
+  const char* body;
+  smtp_result_fn callback_fn;
+  void* callback_arg;
+  /** If this is != 0, data is *not* copied into an extra buffer
+   * but used from the pointers supplied in this struct.
+   * This means less memory usage, but data must stay untouched until
+   * the callback function is called. */
+  u8_t static_data;
+};
+
+void smtp_set_server_addr(const char* server);
+void smtp_set_server_port(u16_t port);
+err_t smtp_set_auth(const char* username, const char* pass);
+err_t smtp_send_mail(const char *from, const char* to, const char* subject, const char* body,
+                     smtp_result_fn callback_fn, void* callback_arg);
+err_t smtp_send_mail_static(const char *from, const char* to, const char* subject, const char* body,
+                     smtp_result_fn callback_fn, void* callback_arg);
+void smtp_send_mail_int(void *arg);
+#if LWIP_DEBUG
+const char* smtp_result_str(u8_t smtp_result);
+#endif
+
+#endif /* __SMTP_H__ */

src/lwip-1.4.1/apps/snmp_private_mib/lwip_prvmib.c

@@ -0,0 +1,604 @@
+/**
+ * @file
+ * lwip Private MIB 
+ *
+ * @todo create MIB file for this example
+ * @note the lwip enterprise tree root (26381) is owned by the lwIP project.
+ * It is NOT allowed to allocate new objects under this ID (26381) without our,
+ * the lwip developers, permission!
+ *
+ * Please apply for your own ID with IANA: http://www.iana.org/numbers.html
+ *  
+ * lwip        OBJECT IDENTIFIER ::= { enterprises 26381 }
+ * example     OBJECT IDENTIFIER ::= { lwip 1 }
+ */
+ 
+/*
+ * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * Author: Christiaan Simons <christiaan.simons@axon.tv>
+ */
+
+#include "private_mib.h"
+
+#if LWIP_SNMP
+
+/** Directory where the sensor files are */
+#define SENSORS_DIR           "w:\\sensors"
+/** Set to 1 to read sensor values from files (in directory defined by SENSORS_DIR) */
+#define SENSORS_USE_FILES     0
+/** Set to 1 to search sensor files at startup (in directory defined by SENSORS_DIR) */
+#define SENSORS_SEARCH_FILES  0
+
+#if SENSORS_SEARCH_FILES
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <dirent.h>
+#endif /* SENSORS_SEARCH_FILES */
+
+#include <string.h>
+#include <stdio.h>
+
+#include "lwip/snmp_msg.h"
+#include "lwip/snmp_asn1.h"
+
+#if !SENSORS_USE_FILES || !SENSORS_SEARCH_FILES
+/** When not using & searching files, defines the number of sensors */
+#define SENSOR_COUNT 2
+#endif /* !SENSORS_USE_FILES || !SENSORS_SEARCH_FILES */
+#if !SENSORS_USE_FILES
+/** When not using files, contains the values of the sensors */
+s32_t sensor_values[SENSOR_COUNT];
+#endif /* !SENSORS_USE_FILES */
+
+/*
+  This example presents a table for a few (at most 10) sensors.
+  Sensor detection takes place at initialization (once only).
+  Sensors may and can not be added or removed after agent
+  has started. Note this is only a limitation of this crude example,
+  the agent does support dynamic object insertions and removals.
+   
+  You'll need to manually create a directory called "sensors" and
+  a few single line text files with an integer temperature value.
+  The files must be called [0..9].txt. 
+   
+  ./sensors/0.txt [content: 20]
+  ./sensors/3.txt [content: 75]
+    
+  The sensor values may be changed in runtime by editing the 
+  text files in the "sensors" directory.
+*/
+
+
+#define SENSOR_MAX 10
+#define SENSOR_NAME_LEN 20
+
+struct sensor_inf
+{
+  char sensor_files[SENSOR_MAX][SENSOR_NAME_LEN + 1];
+  /* (Sparse) list of sensors (table index),
+   the actual "hot insertion" is done in lwip_privmib_init() */
+  struct mib_list_rootnode sensor_list_rn;
+};
+
+struct sensor_inf sensor_addr_inf =
+{
+  {{0}},
+  {
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    MIB_NODE_LR,
+    0,
+    NULL,
+    NULL,
+    0
+  }
+};
+
+
+static u16_t sensorentry_length(void* addr_inf, u8_t level);
+static s32_t sensorentry_idcmp(void* addr_inf, u8_t level, u16_t idx, s32_t sub_id);
+static void sensorentry_get_subid(void* addr_inf, u8_t level, u16_t idx, s32_t *sub_id);
+
+static void sensorentry_get_object_def_q(void* addr_inf, u8_t rid, u8_t ident_len, s32_t *ident);
+static void sensorentry_get_object_def_a(u8_t rid, u8_t ident_len, s32_t *ident, struct obj_def *od);
+static void sensorentry_get_object_def_pc(u8_t rid, u8_t ident_len, s32_t *ident);
+static void sensorentry_get_value_q(u8_t rid, struct obj_def *od);
+static void sensorentry_get_value_a(u8_t rid, struct obj_def *od, u16_t len, void *value);
+static void sensorentry_get_value_pc(u8_t rid, struct obj_def *od);
+static void sensorentry_set_test_q(u8_t rid, struct obj_def *od);
+static u8_t sensorentry_set_test_a(u8_t rid, struct obj_def *od, u16_t len, void *value);
+static void sensorentry_set_test_pc(u8_t rid, struct obj_def *od);
+static void sensorentry_set_value_q(u8_t rid, struct obj_def *od, u16_t len, void *value);
+static void sensorentry_set_value_a(u8_t rid, struct obj_def *od, u16_t len, void *value);
+static void sensorentry_set_value_pc(u8_t rid, struct obj_def *od);
+
+/* sensorentry .1.3.6.1.4.1.26381.1.1.1 (.level0.level1)
+   where level 0 is the object identifier (temperature) and level 1 the index */
+static struct mib_external_node sensorentry = {
+  &noleafs_get_object_def,
+  &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
+  MIB_NODE_EX,
+  0,
+  &sensor_addr_inf,
+  /* 0 tree_levels (empty table) at power-up,
+     2 when one or more sensors are detected */
+  0,
+  &sensorentry_length,
+  &sensorentry_idcmp,
+  &sensorentry_get_subid,
+  
+  &sensorentry_get_object_def_q,
+  &sensorentry_get_value_q,
+  &sensorentry_set_test_q,
+  &sensorentry_set_value_q,
+
+  &sensorentry_get_object_def_a,
+  &sensorentry_get_value_a,
+  &sensorentry_set_test_a,
+  &sensorentry_set_value_a,
+
+  &sensorentry_get_object_def_pc,
+  &sensorentry_get_value_pc,
+  &sensorentry_set_test_pc,
+  &sensorentry_set_value_pc
+};
+
+/* sensortable .1.3.6.1.4.1.26381.1.1 */
+static const s32_t sensortable_ids[1] = { 1 };
+static struct mib_node* const sensortable_nodes[1] = {
+ (struct mib_node* const)&sensorentry
+};
+static const struct mib_array_node sensortable = {
+  &noleafs_get_object_def,
+  &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
+  MIB_NODE_AR,
+  1,
+  sensortable_ids,
+  sensortable_nodes
+};
+
+/* example .1.3.6.1.4.1.26381.1 */
+static const s32_t example_ids[1] = { 1 };
+static struct mib_node* const example_nodes[1] = {
+  (struct mib_node* const)&sensortable
+};
+static const struct mib_array_node example = {
+  &noleafs_get_object_def,
+  &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
+  MIB_NODE_AR,
+  1,
+  example_ids,
+  example_nodes
+};
+
+/* lwip .1.3.6.1.4.1.26381 */
+static const s32_t lwip_ids[1] = { 1 };
+static struct mib_node* const lwip_nodes[1] = { (struct mib_node* const)&example };
+static const struct mib_array_node lwip = {
+  &noleafs_get_object_def,
+  &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
+  MIB_NODE_AR,
+  1,
+  lwip_ids,
+  lwip_nodes
+};
+
+/* enterprises .1.3.6.1.4.1 */
+static const s32_t enterprises_ids[1] = { 26381 };
+static struct mib_node* const enterprises_nodes[1] = { (struct mib_node* const)&lwip };
+static const struct mib_array_node enterprises = {
+  &noleafs_get_object_def,
+  &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
+  MIB_NODE_AR,
+  1,
+  enterprises_ids,
+  enterprises_nodes
+};
+
+/* private .1.3.6.1.4 */
+static const s32_t private_ids[1] = { 1 };
+static struct mib_node* const private_nodes[1] = { (struct mib_node* const)&enterprises };
+const struct mib_array_node mib_private = {
+  &noleafs_get_object_def,
+  &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
+  MIB_NODE_AR,
+  1,
+  private_ids,
+  private_nodes
+};
+
+
+/**
+ * Initialises this private MIB before use.
+ * @see main.c
+ */
+void
+lwip_privmib_init(void)
+{
+#if SENSORS_USE_FILES && SENSORS_SEARCH_FILES
+  char *buf, *ebuf, *cp;
+  size_t bufsize;
+  int nbytes;
+  struct stat sb;
+  struct dirent *dp;
+  int fd;
+#else /* SENSORS_USE_FILES && SENSORS_SEARCH_FILES */
+  int i;
+#endif /* SENSORS_USE_FILES && SENSORS_SEARCH_FILES */
+
+  printf("SNMP private MIB start, detecting sensors.\n");
+
+#if SENSORS_USE_FILES && SENSORS_SEARCH_FILES
+  /* look for sensors in sensors directory */
+  fd = open(SENSORS_DIR, O_RDONLY);
+  if (fd > -1)
+  {
+    fstat(fd, &sb);
+    bufsize = sb.st_size;
+    if (bufsize < sb.st_blksize)
+    {
+      bufsize = sb.st_blksize;
+    }
+    buf = malloc(bufsize);
+    if (buf != NULL)
+    {
+      do
+      {
+        long base;
+        
+        nbytes = getdirentries(fd, buf, bufsize, &base);
+        if (nbytes > 0)
+        {
+          ebuf = buf + nbytes;
+          cp = buf;
+          while (cp < ebuf)
+          {
+            dp = (struct dirent *)cp;
+            if (isdigit(dp->d_name[0]))
+            {
+              struct mib_list_node *dummy;
+              unsigned char index;
+              
+              index = dp->d_name[0] - '0';
+              snmp_mib_node_insert(&sensor_addr_inf.sensor_list_rn,index,&dummy);
+
+              strncpy(&sensor_addr_inf.sensor_files[index][0],dp->d_name,SENSOR_NAME_LEN);
+              printf("%s\n", sensor_addr_inf.sensor_files[index]);
+            }
+            cp += dp->d_reclen;
+          }
+        } 
+      }
+      while (nbytes > 0);
+    
+      free(buf);
+    }
+    close(fd);
+  }
+#else /* SENSORS_USE_FILES && SENSORS_SEARCH_FILES */
+  for (i = 0; i < SENSOR_COUNT; i++) {
+    struct mib_list_node *dummy;
+    s32_t index = i;
+    char name[256];
+    sprintf(name, "%d.txt", i);
+
+    snmp_mib_node_insert(&sensor_addr_inf.sensor_list_rn, index, &dummy);
+
+    strncpy(&sensor_addr_inf.sensor_files[index][0], name, SENSOR_NAME_LEN);
+    printf("%s\n", sensor_addr_inf.sensor_files[index]);
+#if !SENSORS_USE_FILES
+    /* initialize sensor value to != zero */
+    sensor_values[i] = 11 * (i+1);
+#endif /* !SENSORS_USE_FILES */
+  }
+#endif /* SENSORS_USE_FILE && SENSORS_SEARCH_FILES */
+  if (sensor_addr_inf.sensor_list_rn.count != 0)
+  {
+    /* enable sensor table, 2 tree_levels under this node
+       one for the registers and one for the index */
+    sensorentry.tree_levels = 2;
+  }
+}
+
+
+static u16_t
+sensorentry_length(void* addr_inf, u8_t level)
+{
+  struct sensor_inf *sensors = (struct sensor_inf *)addr_inf;
+
+  if (level == 0)
+  {
+    /* one object (temperature) */
+    return 1;
+  }
+  else if (level == 1)
+  {
+    /* number of sensor indexes */
+    return sensors->sensor_list_rn.count;
+  }
+  else
+  {
+    return 0;
+  }
+}
+
+static s32_t
+sensorentry_idcmp(void* addr_inf, u8_t level, u16_t idx, s32_t sub_id)
+{
+  struct sensor_inf *sensors = (struct sensor_inf *)addr_inf;
+  
+  if (level == 0)
+  {
+    return ((s32_t)(idx + 1) - sub_id);
+  }
+  else if (level == 1)
+  {
+    struct mib_list_node *ln;
+    u16_t i;
+  
+    i = 0;
+    ln = sensors->sensor_list_rn.head;
+    while (i < idx)
+    {
+      i++;
+      ln = ln->next;
+    }
+    LWIP_ASSERT("ln != NULL", ln != NULL);
+    return (ln->objid - sub_id);
+  }
+  else
+  {
+    return -1;
+  }
+}
+
+static void
+sensorentry_get_subid(void* addr_inf, u8_t level, u16_t idx, s32_t *sub_id)
+{
+  struct sensor_inf *sensors = (struct sensor_inf *)addr_inf;
+
+  if (level == 0)
+  {
+    *sub_id = idx + 1;
+  }
+  else if (level == 1)
+  {
+    struct mib_list_node *ln;
+    u16_t i;
+
+    i = 0;
+    ln = sensors->sensor_list_rn.head;
+    while (i < idx)
+    {
+      i++;
+      ln = ln->next;
+    }
+    LWIP_ASSERT("ln != NULL", ln != NULL);
+    *sub_id = ln->objid;
+  }
+}
+
+/**
+ * Async question for object definition
+ */
+static void
+sensorentry_get_object_def_q(void* addr_inf, u8_t rid, u8_t ident_len, s32_t *ident)
+{
+  s32_t sensor_register, sensor_address;
+
+  LWIP_UNUSED_ARG(addr_inf);
+  LWIP_UNUSED_ARG(rid);
+
+  ident_len += 1;
+  ident -= 1;
+
+  /* send request */
+  sensor_register = ident[0];
+  sensor_address = ident[1];
+  LWIP_DEBUGF(SNMP_MIB_DEBUG,("sensor_request reg=%"S32_F" addr=%"S32_F"\n",
+                              sensor_register, sensor_address));
+  /* fake async quesion/answer */
+  snmp_msg_event(rid);
+}
+
+static void
+sensorentry_get_object_def_a(u8_t rid, u8_t ident_len, s32_t *ident, struct obj_def *od)
+{
+  LWIP_UNUSED_ARG(rid);
+
+  /* return to object name, adding index depth (1) */
+  ident_len += 1;
+  ident -= 1;
+  if (ident_len == 2)
+  { 
+    od->id_inst_len = ident_len;
+    od->id_inst_ptr = ident;
+
+    od->instance = MIB_OBJECT_TAB;
+    od->access = MIB_OBJECT_READ_WRITE;
+    od->asn_type = (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_INTEG);
+    od->v_len = sizeof(s32_t);
+  }
+  else
+  {
+    LWIP_DEBUGF(SNMP_MIB_DEBUG,("sensorentry_get_object_def_a: no scalar\n"));
+    od->instance = MIB_OBJECT_NONE;
+  }
+}
+
+static void
+sensorentry_get_object_def_pc(u8_t rid, u8_t ident_len, s32_t *ident)
+{
+  LWIP_UNUSED_ARG(rid);
+  LWIP_UNUSED_ARG(ident_len);
+  LWIP_UNUSED_ARG(ident);
+  /* nop */
+}
+
+static void
+sensorentry_get_value_q(u8_t rid, struct obj_def *od)
+{
+  LWIP_UNUSED_ARG(od);
+
+  /* fake async quesion/answer */
+  snmp_msg_event(rid);
+}
+
+static void
+sensorentry_get_value_a(u8_t rid, struct obj_def *od, u16_t len, void *value)
+{
+  s32_t i;
+  s32_t *temperature = (s32_t *)value;
+#if SENSORS_USE_FILES
+  FILE* sensf;
+  char senspath[sizeof(SENSORS_DIR)+1+SENSOR_NAME_LEN+1] = SENSORS_DIR"/";
+#endif /* SENSORS_USE_FILES */
+
+  LWIP_UNUSED_ARG(rid);
+  LWIP_UNUSED_ARG(len);
+
+  i = od->id_inst_ptr[1];
+#if SENSORS_USE_FILES
+  strncpy(&senspath[sizeof(SENSORS_DIR)],
+          sensor_addr_inf.sensor_files[i],
+          SENSOR_NAME_LEN);
+  sensf = fopen(senspath,"r");
+  if (sensf != NULL)
+  {
+    fscanf(sensf,"%"S32_F,temperature);
+    fclose(sensf);
+  }
+#else /* SENSORS_USE_FILES */
+  if (i <= SENSOR_COUNT) {
+    *temperature = sensor_values[i];
+  }
+#endif /* SENSORS_USE_FILES */
+}
+
+static void
+sensorentry_get_value_pc(u8_t rid, struct obj_def *od)
+{
+  LWIP_UNUSED_ARG(rid);
+  LWIP_UNUSED_ARG(od);
+  /* nop */
+}
+
+static void
+sensorentry_set_test_q(u8_t rid, struct obj_def *od)
+{
+  LWIP_UNUSED_ARG(od);
+  /* fake async quesion/answer */
+  snmp_msg_event(rid);
+}
+
+static u8_t
+sensorentry_set_test_a(u8_t rid, struct obj_def *od, u16_t len, void *value)
+{
+  LWIP_UNUSED_ARG(rid);
+  LWIP_UNUSED_ARG(od);
+  LWIP_UNUSED_ARG(len);
+  LWIP_UNUSED_ARG(value);
+  /* sensors are read-only */
+  return 1; /* 0 -> read only, != 0 -> read/write */
+}
+
+static void
+sensorentry_set_test_pc(u8_t rid, struct obj_def *od)
+{
+  LWIP_UNUSED_ARG(rid);
+  LWIP_UNUSED_ARG(od);
+  /* nop */
+}
+
+static void
+sensorentry_set_value_q(u8_t rid, struct obj_def *od, u16_t len, void *value)
+{
+  LWIP_UNUSED_ARG(rid);
+  LWIP_UNUSED_ARG(od);
+  LWIP_UNUSED_ARG(len);
+  LWIP_UNUSED_ARG(value);
+  /* fake async quesion/answer */
+  snmp_msg_event(rid);
+}
+
+static void
+sensorentry_set_value_a(u8_t rid, struct obj_def *od, u16_t len, void *value)
+{
+  s32_t i;
+  s32_t *temperature = (s32_t *)value;
+#if SENSORS_USE_FILES
+  FILE* sensf;
+  char senspath[sizeof(SENSORS_DIR)+1+SENSOR_NAME_LEN+1] = SENSORS_DIR"/";
+#endif /* SENSORS_USE_FILES */
+
+  LWIP_UNUSED_ARG(rid);
+  LWIP_UNUSED_ARG(len);
+
+  i = od->id_inst_ptr[1];
+#if SENSORS_USE_FILES
+  strncpy(&senspath[sizeof(SENSORS_DIR)],
+          sensor_addr_inf.sensor_files[i],
+          SENSOR_NAME_LEN);
+  sensf = fopen(senspath, "w");
+  if (sensf != NULL)
+  {
+    fprintf(sensf, "%"S32_F, temperature);
+    fclose(sensf);
+  }
+#else /* SENSORS_USE_FILES */
+  if (i <= SENSOR_COUNT) {
+    sensor_values[i] = *temperature;
+  }
+#endif /* SENSORS_USE_FILES */
+}
+
+static void
+sensorentry_set_value_pc(u8_t rid, struct obj_def *od)
+{
+  LWIP_UNUSED_ARG(rid);
+  LWIP_UNUSED_ARG(od);
+  /* nop */
+}
+
+#endif /* LWIP_SNMP */

src/lwip-1.4.1/apps/snmp_private_mib/private_mib.h

@@ -0,0 +1,28 @@
+/**
+ * @file
+ * Exports Private lwIP MIB 
+ */
+
+#ifndef __LWIP_PRIVATE_MIB_H__
+#define __LWIP_PRIVATE_MIB_H__
+
+#include "arch/cc.h"
+#include "lwip/opt.h"
+
+#if LWIP_SNMP
+#include "lwip/snmp_structs.h"
+extern const struct mib_array_node mib_private;
+
+/** @todo remove this?? */
+struct private_msg
+{
+  u8_t dummy;
+};
+
+void lwip_privmib_init(void);
+
+#define SNMP_PRIVATE_MIB_INIT() lwip_privmib_init()
+
+#endif
+
+#endif

src/lwip-1.4.1/apps/sntp/sntp.c

@@ -0,0 +1,606 @@
+/**
+ * @file
+ * SNTP client module
+ *
+ * This is simple "SNTP" client for the lwIP raw API.
+ * It is a minimal implementation of SNTPv4 as specified in RFC 4330.
+ * 
+ * For a list of some public NTP servers, see this link :
+ * http://support.ntp.org/bin/view/Servers/NTPPoolServers
+ *
+ * @todo:
+ * - set/change servers at runtime
+ * - complete SNTP_CHECK_RESPONSE checks 3 and 4
+ * - support broadcast/multicast mode?
+ */
+
+/*
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Simon Goldschmidt (lwIP raw API part)
+ */
+
+#include "lwip/opt.h"
+
+#include "sntp.h"
+
+#include "lwip/timers.h"
+#include "lwip/udp.h"
+#include "lwip/dns.h"
+#include "lwip/ip_addr.h"
+#include "lwip/pbuf.h"
+
+#include <string.h>
+#include <time.h>
+
+#if LWIP_UDP
+
+/**
+ * SNTP_DEBUG: Enable debugging for SNTP.
+ */
+#ifndef SNTP_DEBUG
+#define SNTP_DEBUG                  LWIP_DBG_OFF
+#endif
+
+/** SNTP server port */
+#ifndef SNTP_PORT
+#define SNTP_PORT                   123
+#endif
+
+/** Set this to 1 to allow SNTP_SERVER_ADDRESS to be a DNS name */
+#ifndef SNTP_SERVER_DNS
+#define SNTP_SERVER_DNS             0
+#endif
+
+/** Set this to 1 to support more than one server */
+#ifndef SNTP_SUPPORT_MULTIPLE_SERVERS
+#define SNTP_SUPPORT_MULTIPLE_SERVERS 0
+#endif
+
+/** \def SNTP_SERVER_ADDRESS
+ * \brief SNTP server address:
+ * - as IPv4 address in "u32_t" format
+ * - as a DNS name if SNTP_SERVER_DNS is set to 1
+ * May contain multiple server names (e.g. "pool.ntp.org","second.time.server")
+ */
+#ifndef SNTP_SERVER_ADDRESS
+#if SNTP_SERVER_DNS
+#define SNTP_SERVER_ADDRESS         "pool.ntp.org"
+#else
+#define SNTP_SERVER_ADDRESS         "213.161.194.93" /* pool.ntp.org */
+#endif
+#endif
+
+/** Sanity check:
+ * Define this to
+ * - 0 to turn off sanity checks (default; smaller code)
+ * - >= 1 to check address and port of the response packet to ensure the
+ *        response comes from the server we sent the request to.
+ * - >= 2 to check returned Originate Timestamp against Transmit Timestamp
+ *        sent to the server (to ensure response to older request).
+ * - >= 3 @todo: discard reply if any of the LI, Stratum, or Transmit Timestamp
+ *        fields is 0 or the Mode field is not 4 (unicast) or 5 (broadcast).
+ * - >= 4 @todo: to check that the Root Delay and Root Dispersion fields are each
+ *        greater than or equal to 0 and less than infinity, where infinity is
+ *        currently a cozy number like one second. This check avoids using a
+ *        server whose synchronization source has expired for a very long time.
+ */
+#ifndef SNTP_CHECK_RESPONSE
+#define SNTP_CHECK_RESPONSE         0
+#endif
+
+/** According to the RFC, this shall be a random delay
+ * between 1 and 5 minutes (in milliseconds) to prevent load peaks.
+ * This can be defined to a random generation function,
+ * which must return the delay in milliseconds as u32_t.
+ * Turned off by default.
+ */
+#ifndef SNTP_STARTUP_DELAY
+#define SNTP_STARTUP_DELAY          0
+#endif
+
+/** SNTP receive timeout - in milliseconds
+ * Also used as retry timeout - this shouldn't be too low.
+ * Default is 3 seconds.
+ */
+#ifndef SNTP_RECV_TIMEOUT
+#define SNTP_RECV_TIMEOUT           3000
+#endif
+
+/** SNTP update delay - in milliseconds
+ * Default is 1 hour.
+ */
+#ifndef SNTP_UPDATE_DELAY
+#define SNTP_UPDATE_DELAY           3600000
+#endif
+#if (SNTP_UPDATE_DELAY < 15000) && !SNTP_SUPPRESS_DELAY_CHECK
+#error "SNTPv4 RFC 4330 enforces a minimum update time of 15 seconds!"
+#endif
+
+/** SNTP macro to change system time and/or the update the RTC clock */
+#ifndef SNTP_SET_SYSTEM_TIME
+#define SNTP_SET_SYSTEM_TIME(sec) ((void)sec)
+#endif
+
+/** SNTP macro to change system time including microseconds */
+#ifdef SNTP_SET_SYSTEM_TIME_US
+#define SNTP_CALC_TIME_US           1
+#define SNTP_RECEIVE_TIME_SIZE      2
+#else
+#define SNTP_SET_SYSTEM_TIME_US(sec, us)
+#define SNTP_CALC_TIME_US           0
+#define SNTP_RECEIVE_TIME_SIZE      1
+#endif
+
+/** SNTP macro to get system time, used with SNTP_CHECK_RESPONSE >= 2
+ * to send in request and compare in response.
+ */
+#ifndef SNTP_GET_SYSTEM_TIME
+#define SNTP_GET_SYSTEM_TIME(sec, us)     do { (sec) = 0; (us) = 0; } while(0)
+#endif
+
+/** Default retry timeout (in milliseconds) if the response
+ * received is invalid.
+ * This is doubled with each retry until SNTP_RETRY_TIMEOUT_MAX is reached.
+ */
+#ifndef SNTP_RETRY_TIMEOUT
+#define SNTP_RETRY_TIMEOUT          SNTP_RECV_TIMEOUT
+#endif
+
+/** Maximum retry timeout (in milliseconds). */
+#ifndef SNTP_RETRY_TIMEOUT_MAX
+#define SNTP_RETRY_TIMEOUT_MAX      (SNTP_RETRY_TIMEOUT * 10)
+#endif
+
+/** Increase retry timeout with every retry sent
+ * Default is on to conform to RFC.
+ */
+#ifndef SNTP_RETRY_TIMEOUT_EXP
+#define SNTP_RETRY_TIMEOUT_EXP      1
+#endif
+
+/* the various debug levels for this file */
+#define SNTP_DEBUG_TRACE        (SNTP_DEBUG | LWIP_DBG_TRACE)
+#define SNTP_DEBUG_STATE        (SNTP_DEBUG | LWIP_DBG_STATE)
+#define SNTP_DEBUG_WARN         (SNTP_DEBUG | LWIP_DBG_LEVEL_WARNING)
+#define SNTP_DEBUG_WARN_STATE   (SNTP_DEBUG | LWIP_DBG_LEVEL_WARNING | LWIP_DBG_STATE)
+#define SNTP_DEBUG_SERIOUS      (SNTP_DEBUG | LWIP_DBG_LEVEL_SERIOUS)
+
+#define SNTP_ERR_KOD                1
+
+/* SNTP protocol defines */
+#define SNTP_MSG_LEN                48
+
+#define SNTP_OFFSET_LI_VN_MODE      0
+#define SNTP_LI_MASK                0xC0
+#define SNTP_LI_NO_WARNING          0x00
+#define SNTP_LI_LAST_MINUTE_61_SEC  0x01
+#define SNTP_LI_LAST_MINUTE_59_SEC  0x02
+#define SNTP_LI_ALARM_CONDITION     0x03 /* (clock not synchronized) */
+
+#define SNTP_VERSION_MASK           0x38
+#define SNTP_VERSION                (4/* NTP Version 4*/<<3) 
+
+#define SNTP_MODE_MASK              0x07
+#define SNTP_MODE_CLIENT            0x03
+#define SNTP_MODE_SERVER            0x04
+#define SNTP_MODE_BROADCAST         0x05
+
+#define SNTP_OFFSET_STRATUM         1
+#define SNTP_STRATUM_KOD            0x00
+
+#define SNTP_OFFSET_ORIGINATE_TIME  24
+#define SNTP_OFFSET_RECEIVE_TIME    32
+#define SNTP_OFFSET_TRANSMIT_TIME   40
+
+/* number of seconds between 1900 and 1970 */
+#define DIFF_SEC_1900_1970         (2208988800UL)
+
+/**
+ * SNTP packet format (without optional fields)
+ * Timestamps are coded as 64 bits:
+ * - 32 bits seconds since Jan 01, 1970, 00:00
+ * - 32 bits seconds fraction (0-padded)
+ * For future use, if the MSB in the seconds part is set, seconds are based
+ * on Feb 07, 2036, 06:28:16.
+ */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct sntp_msg {
+ PACK_STRUCT_FIELD(u8_t           li_vn_mode);
+ PACK_STRUCT_FIELD(u8_t           stratum);
+ PACK_STRUCT_FIELD(u8_t           poll);
+ PACK_STRUCT_FIELD(u8_t           precision);
+ PACK_STRUCT_FIELD(u32_t          root_delay);
+ PACK_STRUCT_FIELD(u32_t          root_dispersion);
+ PACK_STRUCT_FIELD(u32_t          reference_identifier);
+ PACK_STRUCT_FIELD(u32_t          reference_timestamp[2]);
+ PACK_STRUCT_FIELD(u32_t          originate_timestamp[2]);
+ PACK_STRUCT_FIELD(u32_t          receive_timestamp[2]);
+ PACK_STRUCT_FIELD(u32_t          transmit_timestamp[2]);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+/* function prototypes */
+static void sntp_request(void *arg);
+
+/** The UDP pcb used by the SNTP client */
+static struct udp_pcb* sntp_pcb;
+/** Addresses of servers */
+static char* sntp_server_addresses[] = {SNTP_SERVER_ADDRESS};
+#if SNTP_SUPPORT_MULTIPLE_SERVERS
+/** The currently used server (initialized to 0) */
+static u8_t sntp_current_server;
+static u8_t sntp_num_servers = sizeof(sntp_server_addresses)/sizeof(char*);
+#else /* SNTP_SUPPORT_MULTIPLE_SERVERS */
+#define sntp_current_server 0
+#endif /* SNTP_SUPPORT_MULTIPLE_SERVERS */
+
+#if SNTP_RETRY_TIMEOUT_EXP
+#define SNTP_RESET_RETRY_TIMEOUT() sntp_retry_timeout = SNTP_RETRY_TIMEOUT
+/** Retry time, initialized with SNTP_RETRY_TIMEOUT and doubled with each retry. */
+static u32_t sntp_retry_timeout;
+#else /* SNTP_RETRY_TIMEOUT_EXP */
+#define SNTP_RESET_RETRY_TIMEOUT()
+#define sntp_retry_timeout SNTP_RETRY_TIMEOUT
+#endif /* SNTP_RETRY_TIMEOUT_EXP */
+
+#if SNTP_CHECK_RESPONSE >= 1
+/** Saves the last server address to compare with response */
+static ip_addr_t sntp_last_server_address;
+#endif /* SNTP_CHECK_RESPONSE >= 1 */
+
+#if SNTP_CHECK_RESPONSE >= 2
+/** Saves the last timestamp sent (which is sent back by the server)
+ * to compare against in response */
+static u32_t sntp_last_timestamp_sent[2];
+#endif /* SNTP_CHECK_RESPONSE >= 2 */
+
+/**
+ * SNTP processing of received timestamp
+ */
+static void
+sntp_process(u32_t *receive_timestamp)
+{
+  /* convert SNTP time (1900-based) to unix GMT time (1970-based)
+   * @todo: if MSB is 1, SNTP time is 2036-based!
+   */
+  time_t t = (ntohl(receive_timestamp[0]) - DIFF_SEC_1900_1970);
+
+#if SNTP_CALC_TIME_US
+  u32_t us = ntohl(receive_timestamp[1]) / 4295;
+  SNTP_SET_SYSTEM_TIME_US(t, us);
+  /* display local time from GMT time */
+  LWIP_DEBUGF(SNTP_DEBUG_TRACE, ("sntp_process: %s, %"U32_F" us", ctime(&t), us));
+
+#else /* SNTP_CALC_TIME_US */
+
+  /* change system time and/or the update the RTC clock */
+  SNTP_SET_SYSTEM_TIME(t);
+  /* display local time from GMT time */
+  LWIP_DEBUGF(SNTP_DEBUG_TRACE, ("sntp_process: %s", ctime(&t)));
+#endif /* SNTP_CALC_TIME_US */
+}
+
+/**
+ * Initialize request struct to be sent to server.
+ */
+static void
+sntp_initialize_request(struct sntp_msg *req)
+{
+  memset(req, 0, SNTP_MSG_LEN);
+  req->li_vn_mode = SNTP_LI_NO_WARNING | SNTP_VERSION | SNTP_MODE_CLIENT;
+
+#if SNTP_CHECK_RESPONSE >= 2
+  {
+    u32_t sntp_time_sec, sntp_time_us;
+    /* fill in transmit timestamp and save it in 'sntp_last_timestamp_sent' */
+    SNTP_GET_SYSTEM_TIME(sntp_time_sec, sntp_time_us);
+    sntp_last_timestamp_sent[0] = htonl(sntp_time_sec + DIFF_SEC_1900_1970);
+    req->transmit_timestamp[0] = sntp_last_timestamp_sent[0];
+    /* we send/save us instead of fraction to be faster... */
+    sntp_last_timestamp_sent[1] = htonl(sntp_time_us);
+    req->transmit_timestamp[1] = sntp_last_timestamp_sent[1];
+  }
+#endif /* SNTP_CHECK_RESPONSE >= 2 */
+}
+
+/**
+ * Retry: send a new request (and increase retry timeout).
+ *
+ * @param arg is unused (only necessary to conform to sys_timeout)
+ */
+static void
+sntp_retry(void* arg)
+{
+  LWIP_UNUSED_ARG(arg);
+
+  LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_retry: Next request will be sent in %"U32_F" ms\n",
+    sntp_retry_timeout));
+
+  /* set up a timer to send a retry and increase the retry delay */
+  sys_timeout(sntp_retry_timeout, sntp_request, NULL);
+
+#if SNTP_RETRY_TIMEOUT_EXP
+  {
+    u32_t new_retry_timeout;
+    /* increase the timeout for next retry */
+    new_retry_timeout = sntp_retry_timeout << 1;
+    /* limit to maximum timeout and prevent overflow */
+    if ((new_retry_timeout <= SNTP_RETRY_TIMEOUT_MAX) &&
+        (new_retry_timeout > sntp_retry_timeout)) {
+      sntp_retry_timeout = new_retry_timeout;
+    }
+  }
+#endif /* SNTP_RETRY_TIMEOUT_EXP */
+}
+
+#if SNTP_SUPPORT_MULTIPLE_SERVERS
+/**
+ * If Kiss-of-Death is received (or another packet parsing error),
+ * try the next server or retry the current server and increase the retry
+ * timeout if only one server is available.
+ *
+ * @param arg is unused (only necessary to conform to sys_timeout)
+ */
+static void
+sntp_try_next_server(void* arg)
+{
+  LWIP_UNUSED_ARG(arg);
+
+  if (sntp_num_servers > 1) {
+    /* new server: reset retry timeout */
+    SNTP_RESET_RETRY_TIMEOUT();
+    sntp_current_server++;
+    if (sntp_current_server >= sntp_num_servers) {
+      sntp_current_server = 0;
+    }
+    LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_try_next_server: Sending request to server %"U16_F"\n",
+      (u16_t)sntp_current_server));
+    /* instantly send a request to the next server */
+    sntp_request(NULL);
+  } else {
+    sntp_retry(NULL);
+  }
+}
+#else /* SNTP_SUPPORT_MULTIPLE_SERVERS */
+/* Always retry on error if only one server is supported */
+#define sntp_try_next_server    sntp_retry
+#endif /* SNTP_SUPPORT_MULTIPLE_SERVERS */
+
+/** UDP recv callback for the sntp pcb */
+static void
+sntp_recv(void *arg, struct udp_pcb* pcb, struct pbuf *p, ip_addr_t *addr, u16_t port)
+{
+  u8_t mode;
+  u8_t stratum;
+  u32_t receive_timestamp[SNTP_RECEIVE_TIME_SIZE];
+  err_t err;
+
+  LWIP_UNUSED_ARG(arg);
+  LWIP_UNUSED_ARG(pcb);
+
+  /* packet received: stop retry timeout  */
+  sys_untimeout(sntp_try_next_server, NULL);
+  sys_untimeout(sntp_request, NULL);
+
+  err = ERR_ARG;
+#if SNTP_CHECK_RESPONSE >= 1
+  /* check server address and port */
+  if (ip_addr_cmp(addr, &sntp_last_server_address) &&
+    (port == SNTP_PORT))
+#else /* SNTP_CHECK_RESPONSE >= 1 */
+  LWIP_UNUSED_ARG(addr);
+  LWIP_UNUSED_ARG(port);
+#endif /* SNTP_CHECK_RESPONSE >= 1 */
+  {
+    /* process the response */
+    if (p->tot_len == SNTP_MSG_LEN) {
+      pbuf_copy_partial(p, &mode, 1, SNTP_OFFSET_LI_VN_MODE);
+      mode &= SNTP_MODE_MASK;
+      /* if this is a SNTP response... */
+      if ((mode == SNTP_MODE_SERVER) ||
+          (mode == SNTP_MODE_BROADCAST)) {
+        pbuf_copy_partial(p, &stratum, 1, SNTP_OFFSET_STRATUM);
+        if (stratum == SNTP_STRATUM_KOD) {
+          /* Kiss-of-death packet. Use another server or increase UPDATE_DELAY. */
+          err = SNTP_ERR_KOD;
+          LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_recv: Received Kiss-of-Death\n"));
+        } else {
+#if SNTP_CHECK_RESPONSE >= 2
+          /* check originate_timetamp against sntp_last_timestamp_sent */
+          u32_t originate_timestamp[2];
+          pbuf_copy_partial(p, &originate_timestamp, 8, SNTP_OFFSET_ORIGINATE_TIME);
+          if ((originate_timestamp[0] != sntp_last_timestamp_sent[0]) ||
+              (originate_timestamp[1] != sntp_last_timestamp_sent[1]))
+          {
+            LWIP_DEBUGF(SNTP_DEBUG_WARN, ("sntp_recv: Invalid originate timestamp in response\n"));
+          } else
+#endif /* SNTP_CHECK_RESPONSE >= 2 */
+          /* @todo: add code for SNTP_CHECK_RESPONSE >= 3 and >= 4 here */
+          {
+            /* correct answer */
+            err = ERR_OK;
+            pbuf_copy_partial(p, &receive_timestamp, SNTP_RECEIVE_TIME_SIZE * 4, SNTP_OFFSET_RECEIVE_TIME);
+          }
+        }
+      } else {
+        LWIP_DEBUGF(SNTP_DEBUG_WARN, ("sntp_recv: Invalid mode in response: %"U16_F"\n", (u16_t)mode));
+      }
+    } else {
+      LWIP_DEBUGF(SNTP_DEBUG_WARN, ("sntp_recv: Invalid packet length: %"U16_F"\n", p->tot_len));
+    }
+  }
+  pbuf_free(p);
+  if (err == ERR_OK) {
+    /* Correct response, reset retry timeout */
+    SNTP_RESET_RETRY_TIMEOUT();
+
+    sntp_process(receive_timestamp);
+
+    /* Set up timeout for next request */
+    sys_timeout((u32_t)SNTP_UPDATE_DELAY, sntp_request, NULL);
+    LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_recv: Scheduled next time request: %"U32_F" ms\n",
+      (u32_t)SNTP_UPDATE_DELAY));
+  } else if (err == SNTP_ERR_KOD) {
+    /* Kiss-of-death packet. Use another server or increase UPDATE_DELAY. */
+    sntp_try_next_server(NULL);
+  } else {
+    /* another error, try the same server again */
+    sntp_retry(NULL);
+  }
+}
+
+/** Actually send an sntp request to a server.
+ *
+ * @param server_addr resolved IP address of the SNTP server
+ */
+static void
+sntp_send_request(ip_addr_t *server_addr)
+{
+  struct pbuf* p;
+  p = pbuf_alloc(PBUF_TRANSPORT, SNTP_MSG_LEN, PBUF_RAM);
+  if (p != NULL) {
+    struct sntp_msg *sntpmsg = (struct sntp_msg *)p->payload;
+    LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_send_request: Sending request to server\n"));
+    /* initialize request message */
+    sntp_initialize_request(sntpmsg);
+    /* send request */
+    udp_sendto(sntp_pcb, p, server_addr, SNTP_PORT);
+    /* free the pbuf after sending it */
+    pbuf_free(p);
+    /* set up receive timeout: try next server or retry on timeout */
+    sys_timeout((u32_t)SNTP_RECV_TIMEOUT, sntp_try_next_server, NULL);
+#if SNTP_CHECK_RESPONSE >= 1
+    /* save server address to verify it in sntp_recv */ 
+    ip_addr_set(&sntp_last_server_address, server_addr);
+#endif /* SNTP_CHECK_RESPONSE >= 1 */
+  } else {
+    LWIP_DEBUGF(SNTP_DEBUG_SERIOUS, ("sntp_send_request: Out of memory, trying again in %"U32_F" ms\n",
+      (u32_t)SNTP_RETRY_TIMEOUT));
+    /* out of memory: set up a timer to send a retry */
+    sys_timeout((u32_t)SNTP_RETRY_TIMEOUT, sntp_request, NULL);
+  }
+}
+
+#if SNTP_SERVER_DNS
+/**
+ * DNS found callback when using DNS names as server address.
+ */
+static void
+sntp_dns_found(const char* hostname, ip_addr_t *ipaddr, void *arg)
+{
+  LWIP_UNUSED_ARG(hostname);
+  LWIP_UNUSED_ARG(arg);
+
+  if (ipaddr != NULL) {
+    /* Address resolved, send request */
+    LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_dns_found: Server address resolved, sending request\n"));
+    sntp_send_request(ipaddr);
+  } else {
+    /* DNS resolving failed -> try another server */
+    LWIP_DEBUGF(SNTP_DEBUG_WARN_STATE, ("sntp_dns_found: Failed to resolve server address resolved, trying next server\n"));
+    sntp_try_next_server(NULL);
+  }
+}
+#endif /* SNTP_SERVER_DNS */
+
+/**
+ * Send out an sntp request.
+ *
+ * @param arg is unused (only necessary to conform to sys_timeout)
+ */
+static void
+sntp_request(void *arg)
+{
+  ip_addr_t sntp_server_address;
+  err_t err;
+
+  LWIP_UNUSED_ARG(arg);
+
+  /* initialize SNTP server address */
+#if SNTP_SERVER_DNS
+  err = dns_gethostbyname(sntp_server_addresses[sntp_current_server], &sntp_server_address,
+    sntp_dns_found, NULL);
+  if (err == ERR_INPROGRESS) {
+    /* DNS request sent, wait for sntp_dns_found being called */
+    LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_request: Waiting for server address to be resolved.\n"));
+    return;
+  }
+#else /* SNTP_SERVER_DNS */
+  err = ipaddr_aton(sntp_server_addresses[sntp_current_server], &sntp_server_address)
+    ? ERR_OK : ERR_ARG;
+
+#endif /* SNTP_SERVER_DNS */
+
+  if (err == ERR_OK) {
+    sntp_send_request(&sntp_server_address);
+  } else {
+    /* address conversion failed, try another server */
+    LWIP_DEBUGF(SNTP_DEBUG_WARN_STATE, ("sntp_request: Invalid server address, trying next server.\n"));
+    sys_timeout((u32_t)SNTP_RETRY_TIMEOUT, sntp_try_next_server, NULL);
+  }
+}
+
+/**
+ * Initialize this module.
+ * Send out request instantly or after SNTP_STARTUP_DELAY.
+ */
+void
+sntp_init(void)
+{
+  if (sntp_pcb == NULL) {
+    SNTP_RESET_RETRY_TIMEOUT();
+    sntp_pcb = udp_new();
+    LWIP_ASSERT("Failed to allocate udp pcb for sntp client", sntp_pcb != NULL);
+    if (sntp_pcb != NULL) {
+      udp_recv(sntp_pcb, sntp_recv, NULL);
+#if SNTP_STARTUP_DELAY
+      sys_timeout((u32_t)SNTP_STARTUP_DELAY, sntp_request, NULL);
+#else
+      sntp_request(NULL);
+#endif
+    }
+  }
+}
+
+/**
+ * Stop this module.
+ */
+void
+sntp_stop(void)
+{
+  if (sntp_pcb != NULL) {
+    sys_untimeout(sntp_request, NULL);
+    udp_remove(sntp_pcb);
+    sntp_pcb = NULL;
+  }
+}
+#endif /* LWIP_UDP */

src/lwip-1.4.1/apps/sntp/sntp.h

@@ -0,0 +1,15 @@
+#ifndef __SNTP_H__
+#define __SNTP_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void sntp_init(void);
+void sntp_stop(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __SNTP_H__ */

src/lwip-1.4.1/apps/socket_examples/socket_examples.c

@@ -0,0 +1,480 @@
+
+#include "socket_examples.h"
+
+#include "lwip/opt.h"
+
+#if LWIP_SOCKET
+
+#include "lwip/sockets.h"
+#include "lwip/sys.h"
+
+#include <string.h>
+#include <stdio.h>
+
+#ifndef SOCK_TARGET_HOST
+#define SOCK_TARGET_HOST  "192.168.1.1"
+#endif
+
+#ifndef SOCK_TARGET_PORT
+#define SOCK_TARGET_PORT  80
+#endif
+
+/** This is an example function that tests
+    blocking- and nonblocking connect. */
+static void
+sockex_nonblocking_connect(void *arg)
+{
+  int s;
+  int ret;
+  u32_t opt;
+  struct sockaddr_in addr;
+  fd_set readset;
+  fd_set writeset;
+  fd_set errset;
+  struct timeval tv;
+  u32_t ticks_a, ticks_b;
+  int err;
+
+  LWIP_UNUSED_ARG(arg);
+  /* set up address to connect to */
+  memset(&addr, 0, sizeof(addr));
+  addr.sin_len = sizeof(addr);
+  addr.sin_family = AF_INET;
+  addr.sin_port = PP_HTONS(SOCK_TARGET_PORT);
+  addr.sin_addr.s_addr = inet_addr(SOCK_TARGET_HOST);
+
+  /* first try blocking: */
+
+  /* create the socket */
+  s = lwip_socket(AF_INET, SOCK_STREAM, 0);
+  LWIP_ASSERT("s >= 0", s >= 0);
+
+  /* connect */
+  ret = lwip_connect(s, (struct sockaddr*)&addr, sizeof(addr));
+  /* should succeed */
+  LWIP_ASSERT("ret == 0", ret == 0);
+
+  /* write something */
+  ret = lwip_write(s, "test", 4);
+  LWIP_ASSERT("ret == 4", ret == 4);
+
+  /* close */
+  ret = lwip_close(s);
+  LWIP_ASSERT("ret == 0", ret == 0);
+
+  /* now try nonblocking and close before being connected */
+
+  /* create the socket */
+  s = lwip_socket(AF_INET, SOCK_STREAM, 0);
+  LWIP_ASSERT("s >= 0", s >= 0);
+  /* nonblocking */
+  opt = lwip_fcntl(s, F_GETFL, 0);
+  LWIP_ASSERT("ret != -1", ret != -1);
+  opt |= O_NONBLOCK;
+  ret = lwip_fcntl(s, F_SETFL, opt);
+  LWIP_ASSERT("ret != -1", ret != -1);
+  /* connect */
+  ret = lwip_connect(s, (struct sockaddr*)&addr, sizeof(addr));
+  /* should have an error: "inprogress" */
+  LWIP_ASSERT("ret == -1", ret == -1);
+  err = errno;
+  LWIP_ASSERT("errno == EINPROGRESS", err == EINPROGRESS);
+  /* close */
+  ret = lwip_close(s);
+  LWIP_ASSERT("ret == 0", ret == 0);
+  /* try to close again, should fail with EBADF */
+  ret = lwip_close(s);
+  LWIP_ASSERT("ret == -1", ret == -1);
+  err = errno;
+  LWIP_ASSERT("errno == EBADF", err == EBADF);
+  printf("closing socket in nonblocking connect succeeded\n");
+
+  /* now try nonblocking, connect should succeed:
+     this test only works if it is fast enough, i.e. no breakpoints, please! */
+
+  /* create the socket */
+  s = lwip_socket(AF_INET, SOCK_STREAM, 0);
+  LWIP_ASSERT("s >= 0", s >= 0);
+
+  /* nonblocking */
+  opt = 1;
+  ret = lwip_ioctl(s, FIONBIO, &opt);
+  LWIP_ASSERT("ret == 0", ret == 0);
+
+  /* connect */
+  ret = lwip_connect(s, (struct sockaddr*)&addr, sizeof(addr));
+  /* should have an error: "inprogress" */
+  LWIP_ASSERT("ret == -1", ret == -1);
+  err = errno;
+  LWIP_ASSERT("errno == EINPROGRESS", err == EINPROGRESS);
+
+  /* write should fail, too */
+  ret = lwip_write(s, "test", 4);
+  LWIP_ASSERT("ret == -1", ret == -1);
+  err = errno;
+  LWIP_ASSERT("errno == EINPROGRESS", err == EINPROGRESS);
+
+  FD_ZERO(&readset);
+  FD_SET(s, &readset);
+  FD_ZERO(&writeset);
+  FD_SET(s, &writeset);
+  FD_ZERO(&errset);
+  FD_SET(s, &errset);
+  tv.tv_sec = 0;
+  tv.tv_usec = 0;
+  /* select without waiting should fail */
+  ret = lwip_select(s + 1, &readset, &writeset, &errset, &tv);
+  LWIP_ASSERT("ret == 0", ret == 0);
+  LWIP_ASSERT("!FD_ISSET(s, &writeset)", !FD_ISSET(s, &writeset));
+  LWIP_ASSERT("!FD_ISSET(s, &readset)", !FD_ISSET(s, &readset));
+  LWIP_ASSERT("!FD_ISSET(s, &errset)", !FD_ISSET(s, &errset));
+
+  FD_ZERO(&readset);
+  FD_SET(s, &readset);
+  FD_ZERO(&writeset);
+  FD_SET(s, &writeset);
+  FD_ZERO(&errset);
+  FD_SET(s, &errset);
+  ticks_a = sys_now();
+  /* select with waiting should succeed */
+  ret = lwip_select(s + 1, &readset, &writeset, &errset, NULL);
+  ticks_b = sys_now();
+  LWIP_ASSERT("ret == 1", ret == 1);
+  LWIP_ASSERT("FD_ISSET(s, &writeset)", FD_ISSET(s, &writeset));
+  LWIP_ASSERT("!FD_ISSET(s, &readset)", !FD_ISSET(s, &readset));
+  LWIP_ASSERT("!FD_ISSET(s, &errset)", !FD_ISSET(s, &errset));
+
+  /* now write should succeed */
+  ret = lwip_write(s, "test", 4);
+  LWIP_ASSERT("ret == 4", ret == 4);
+
+  /* close */
+  ret = lwip_close(s);
+  LWIP_ASSERT("ret == 0", ret == 0);
+
+  printf("select() needed %d ticks to return writable\n", ticks_b - ticks_a);
+
+
+  /* now try nonblocking to invalid address:
+     this test only works if it is fast enough, i.e. no breakpoints, please! */
+
+  /* create the socket */
+  s = lwip_socket(AF_INET, SOCK_STREAM, 0);
+  LWIP_ASSERT("s >= 0", s >= 0);
+
+  /* nonblocking */
+  opt = 1;
+  ret = lwip_ioctl(s, FIONBIO, &opt);
+  LWIP_ASSERT("ret == 0", ret == 0);
+
+  addr.sin_addr.s_addr++;
+
+  /* connect */
+  ret = lwip_connect(s, (struct sockaddr*)&addr, sizeof(addr));
+  /* should have an error: "inprogress" */
+  LWIP_ASSERT("ret == -1", ret == -1);
+  err = errno;
+  LWIP_ASSERT("errno == EINPROGRESS", err == EINPROGRESS);
+
+  /* write should fail, too */
+  ret = lwip_write(s, "test", 4);
+  LWIP_ASSERT("ret == -1", ret == -1);
+  err = errno;
+  LWIP_ASSERT("errno == EINPROGRESS", err == EINPROGRESS);
+
+  FD_ZERO(&readset);
+  FD_SET(s, &readset);
+  FD_ZERO(&writeset);
+  FD_SET(s, &writeset);
+  FD_ZERO(&errset);
+  FD_SET(s, &errset);
+  tv.tv_sec = 0;
+  tv.tv_usec = 0;
+  /* select without waiting should fail */
+  ret = lwip_select(s + 1, &readset, &writeset, &errset, &tv);
+  LWIP_ASSERT("ret == 0", ret == 0);
+
+  FD_ZERO(&readset);
+  FD_SET(s, &readset);
+  FD_ZERO(&writeset);
+  FD_SET(s, &writeset);
+  FD_ZERO(&errset);
+  FD_SET(s, &errset);
+  ticks_a = sys_now();
+  /* select with waiting should eventually succeed and return errset! */
+  ret = lwip_select(s + 1, &readset, &writeset, &errset, NULL);
+  ticks_b = sys_now();
+  LWIP_ASSERT("ret > 0", ret > 0);
+  LWIP_ASSERT("FD_ISSET(s, &errset)", FD_ISSET(s, &errset));
+  LWIP_ASSERT("!FD_ISSET(s, &readset)", !FD_ISSET(s, &readset));
+  LWIP_ASSERT("!FD_ISSET(s, &writeset)", !FD_ISSET(s, &writeset));
+
+  /* close */
+  ret = lwip_close(s);
+  LWIP_ASSERT("ret == 0", ret == 0);
+
+  printf("select() needed %d ticks to return error\n", ticks_b - ticks_a);
+  printf("all tests done, thread ending\n");
+}
+
+/** This is an example function that tests
+    the recv function (timeout etc.). */
+static void
+sockex_testrecv(void *arg)
+{
+  int s;
+  int ret;
+  int err;
+  int opt;
+  struct sockaddr_in addr;
+  size_t len;
+  char rxbuf[1024];
+  fd_set readset;
+  fd_set errset;
+  struct timeval tv;
+
+  LWIP_UNUSED_ARG(arg);
+  /* set up address to connect to */
+  memset(&addr, 0, sizeof(addr));
+  addr.sin_len = sizeof(addr);
+  addr.sin_family = AF_INET;
+  addr.sin_port = PP_HTONS(SOCK_TARGET_PORT);
+  addr.sin_addr.s_addr = inet_addr(SOCK_TARGET_HOST);
+
+  /* first try blocking: */
+
+  /* create the socket */
+  s = lwip_socket(AF_INET, SOCK_STREAM, 0);
+  LWIP_ASSERT("s >= 0", s >= 0);
+
+  /* connect */
+  ret = lwip_connect(s, (struct sockaddr*)&addr, sizeof(addr));
+  /* should succeed */
+  LWIP_ASSERT("ret == 0", ret == 0);
+
+  /* set recv timeout (100 ms) */
+  opt = 100;
+  ret = lwip_setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, &opt, sizeof(int));
+  LWIP_ASSERT("ret == 0", ret == 0);
+
+  /* write the start of a GET request */
+#define SNDSTR1 "G"
+  len = strlen(SNDSTR1);
+  ret = lwip_write(s, SNDSTR1, len);
+  LWIP_ASSERT("ret == len", ret == (int)len);
+
+  /* should time out if the other side is a good HTTP server */
+  ret = lwip_read(s, rxbuf, 1);
+  LWIP_ASSERT("ret == -1", ret == -1);
+  err = errno;
+  LWIP_ASSERT("errno == EAGAIN", err == EAGAIN);
+
+  /* write the rest of a GET request */
+#define SNDSTR2 "ET / HTTP_1.1\r\n\r\n"
+  len = strlen(SNDSTR2);
+  ret = lwip_write(s, SNDSTR2, len);
+  LWIP_ASSERT("ret == len", ret == (int)len);
+
+  /* wait a while: should be enough for the server to send a response */
+  sys_msleep(1000);
+
+  /* should not time out but receive a response */
+  ret = lwip_read(s, rxbuf, 1024);
+  LWIP_ASSERT("ret > 0", ret > 0);
+
+  /* now select should directly return because the socket is readable */
+  FD_ZERO(&readset);
+  FD_ZERO(&errset);
+  FD_SET(s, &readset);
+  FD_SET(s, &errset);
+  tv.tv_sec = 10;
+  tv.tv_usec = 0;
+  ret = lwip_select(s + 1, &readset, NULL, &errset, &tv);
+  LWIP_ASSERT("ret == 1", ret == 1);
+  LWIP_ASSERT("!FD_ISSET(s, &errset)", !FD_ISSET(s, &errset));
+  LWIP_ASSERT("FD_ISSET(s, &readset)", FD_ISSET(s, &readset));
+
+  /* should not time out but receive a response */
+  ret = lwip_read(s, rxbuf, 1024);
+  /* might receive a second packet for HTTP/1.1 servers */
+  if (ret > 0) {
+    /* should return 0: closed */
+    ret = lwip_read(s, rxbuf, 1024);
+    LWIP_ASSERT("ret == 0", ret == 0);
+  }
+
+  /* close */
+  ret = lwip_close(s);
+  LWIP_ASSERT("ret == 0", ret == 0);
+
+  printf("sockex_testrecv finished successfully\n");
+}
+
+/** helper struct for the 2 functions below (multithreaded: thread-argument) */
+struct sockex_select_helper {
+  int socket;
+  int wait_read;
+  int expect_read;
+  int wait_write;
+  int expect_write;
+  int wait_err;
+  int expect_err;
+  int wait_ms;
+  sys_sem_t sem;
+};
+
+/** helper thread to wait for socket events using select */
+static void
+sockex_select_waiter(void *arg)
+{
+  struct sockex_select_helper *helper = (struct sockex_select_helper *)arg;
+  int ret;
+  fd_set readset;
+  fd_set writeset;
+  fd_set errset;
+  struct timeval tv;
+
+  LWIP_ASSERT("helper != NULL", helper != NULL);
+
+  FD_ZERO(&readset);
+  FD_ZERO(&writeset);
+  FD_ZERO(&errset);
+  if (helper->wait_read) {
+    FD_SET(helper->socket, &readset);
+  }
+  if (helper->wait_write) {
+    FD_SET(helper->socket, &writeset);
+  }
+  if (helper->wait_err) {
+    FD_SET(helper->socket, &errset);
+  }
+
+  tv.tv_sec = helper->wait_ms / 1000;
+  tv.tv_usec = (helper->wait_ms % 1000) * 1000;
+
+  ret = lwip_select(helper->socket, &readset, &writeset, &errset, &tv);
+  if (helper->expect_read || helper->expect_write || helper->expect_err) {
+    LWIP_ASSERT("ret > 0", ret > 0);
+  } else {
+    LWIP_ASSERT("ret == 0", ret == 0);
+  }
+  if (helper->expect_read) {
+    LWIP_ASSERT("FD_ISSET(helper->socket, &readset)", FD_ISSET(helper->socket, &readset));
+  } else {
+    LWIP_ASSERT("!FD_ISSET(helper->socket, &readset)", !FD_ISSET(helper->socket, &readset));
+  }
+  if (helper->expect_write) {
+    LWIP_ASSERT("FD_ISSET(helper->socket, &writeset)", FD_ISSET(helper->socket, &writeset));
+  } else {
+    LWIP_ASSERT("!FD_ISSET(helper->socket, &writeset)", !FD_ISSET(helper->socket, &writeset));
+  }
+  if (helper->expect_err) {
+    LWIP_ASSERT("FD_ISSET(helper->socket, &errset)", FD_ISSET(helper->socket, &errset));
+  } else {
+    LWIP_ASSERT("!FD_ISSET(helper->socket, &errset)", !FD_ISSET(helper->socket, &errset));
+  }
+  sys_sem_signal(&helper->sem);
+}
+
+/** This is an example function that tests
+    more than one thread being active in select. */
+static void
+sockex_testtwoselects(void *arg)
+{
+  int s1;
+  int s2;
+  int ret;
+  struct sockaddr_in addr;
+  size_t len;
+  err_t lwiperr;
+  struct sockex_select_helper h1, h2, h3, h4;
+
+  LWIP_UNUSED_ARG(arg);
+  /* set up address to connect to */
+  memset(&addr, 0, sizeof(addr));
+  addr.sin_len = sizeof(addr);
+  addr.sin_family = AF_INET;
+  addr.sin_port = PP_HTONS(SOCK_TARGET_PORT);
+  addr.sin_addr.s_addr = inet_addr(SOCK_TARGET_HOST);
+
+  /* create the sockets */
+  s1 = lwip_socket(AF_INET, SOCK_STREAM, 0);
+  LWIP_ASSERT("s1 >= 0", s1 >= 0);
+  s2 = lwip_socket(AF_INET, SOCK_STREAM, 0);
+  LWIP_ASSERT("s2 >= 0", s2 >= 0);
+
+  /* connect, should succeed */
+  ret = lwip_connect(s1, (struct sockaddr*)&addr, sizeof(addr));
+  LWIP_ASSERT("ret == 0", ret == 0);
+  ret = lwip_connect(s2, (struct sockaddr*)&addr, sizeof(addr));
+  LWIP_ASSERT("ret == 0", ret == 0);
+
+  /* write the start of a GET request */
+#define SNDSTR1 "G"
+  len = strlen(SNDSTR1);
+  ret = lwip_write(s1, SNDSTR1, len);
+  LWIP_ASSERT("ret == len", ret == (int)len);
+  ret = lwip_write(s2, SNDSTR1, len);
+  LWIP_ASSERT("ret == len", ret == (int)len);
+
+  h1.wait_read  = 1;
+  h1.wait_write = 1;
+  h1.wait_err   = 1;
+  h1.expect_read  = 0;
+  h1.expect_write = 0;
+  h1.expect_err   = 0;
+  lwiperr = sys_sem_new(&h1.sem, 0);
+  LWIP_ASSERT("lwiperr == ERR_OK", lwiperr == ERR_OK);
+  h1.socket = s1;
+  h1.wait_ms = 500;
+
+  h2 = h1;
+  lwiperr = sys_sem_new(&h2.sem, 0);
+  LWIP_ASSERT("lwiperr == ERR_OK", lwiperr == ERR_OK);
+  h2.socket = s2;
+  h2.wait_ms = 1000;
+
+  h3 = h1;
+  lwiperr = sys_sem_new(&h3.sem, 0);
+  LWIP_ASSERT("lwiperr == ERR_OK", lwiperr == ERR_OK);
+  h3.socket = s2;
+  h3.wait_ms = 1500;
+
+  h4 = h1;
+  lwiperr = sys_sem_new(&h4.sem, 0);
+  LWIP_ASSERT("lwiperr == ERR_OK", lwiperr == ERR_OK);
+  h4.socket = s2;
+  h4.wait_ms = 2000;
+
+  /* select: all sockets should time out if the other side is a good HTTP server */
+
+  sys_thread_new("sockex_select_waiter1", sockex_select_waiter, &h2, 0, 0);
+  sys_msleep(100);
+  sys_thread_new("sockex_select_waiter2", sockex_select_waiter, &h1, 0, 0);
+  sys_msleep(100);
+  sys_thread_new("sockex_select_waiter2", sockex_select_waiter, &h4, 0, 0);
+  sys_msleep(100);
+  sys_thread_new("sockex_select_waiter2", sockex_select_waiter, &h3, 0, 0);
+
+  sys_sem_wait(&h1.sem);
+  sys_sem_wait(&h2.sem);
+  sys_sem_wait(&h3.sem);
+  sys_sem_wait(&h4.sem);
+
+  /* close */
+  ret = lwip_close(s1);
+  LWIP_ASSERT("ret == 0", ret == 0);
+  ret = lwip_close(s2);
+  LWIP_ASSERT("ret == 0", ret == 0);
+
+  printf("sockex_testtwoselects finished successfully\n");
+}
+
+void socket_examples_init(void)
+{
+  sys_thread_new("sockex_nonblocking_connect", sockex_nonblocking_connect, NULL, 0, 0);
+  sys_thread_new("sockex_testrecv", sockex_testrecv, NULL, 0, 0);
+  /*sys_thread_new("sockex_testtwoselects", sockex_testtwoselects, NULL, 0, 0);*/
+}
+
+#endif /* LWIP_SOCKETS */

src/lwip-1.4.1/apps/socket_examples/socket_examples.h

@@ -0,0 +1,6 @@
+#ifndef __SOCKET_EXAMPLES_H__
+#define __SOCKET_EXAMPLES_H__
+
+void socket_examples_init(void);
+
+#endif /* __SOCKET_EXAMPLES_H__ */

src/lwip-1.4.1/apps/tcpecho/tcpecho.c

@@ -0,0 +1,96 @@
+/*
+ * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#include "tcpecho.h"
+
+#include "lwip/opt.h"
+
+#if LWIP_NETCONN
+
+#include "lwip/sys.h"
+#include "lwip/api.h"
+/*-----------------------------------------------------------------------------------*/
+static void 
+tcpecho_thread(void *arg)
+{
+  struct netconn *conn, *newconn;
+  err_t err;
+  LWIP_UNUSED_ARG(arg);
+
+  /* Create a new connection identifier. */
+  conn = netconn_new(NETCONN_TCP);
+
+  /* Bind connection to well known port number 7. */
+  netconn_bind(conn, NULL, 7);
+
+  /* Tell connection to go into listening mode. */
+  netconn_listen(conn);
+
+  while (1) {
+
+    /* Grab new connection. */
+    err = netconn_accept(conn, &newconn);
+    /*printf("accepted new connection %p\n", newconn);*/
+    /* Process the new connection. */
+    if (err == ERR_OK) {
+      struct netbuf *buf;
+      void *data;
+      u16_t len;
+      
+      while ((err = netconn_recv(newconn, &buf)) == ERR_OK) {
+        /*printf("Recved\n");*/
+        do {
+             netbuf_data(buf, &data, &len);
+             err = netconn_write(newconn, data, len, NETCONN_COPY);
+#if 0
+            if (err != ERR_OK) {
+              printf("tcpecho: netconn_write: error \"%s\"\n", lwip_strerr(err));
+            }
+#endif
+        } while (netbuf_next(buf) >= 0);
+        netbuf_delete(buf);
+      }
+      /*printf("Got EOF, looping\n");*/ 
+      /* Close connection and discard connection identifier. */
+      netconn_close(newconn);
+      netconn_delete(newconn);
+    }
+  }
+}
+/*-----------------------------------------------------------------------------------*/
+void
+tcpecho_init(void)
+{
+  sys_thread_new("tcpecho_thread", tcpecho_thread, NULL, DEFAULT_THREAD_STACKSIZE, DEFAULT_THREAD_PRIO);
+}
+/*-----------------------------------------------------------------------------------*/
+
+#endif /* LWIP_NETCONN */

src/lwip-1.4.1/apps/tcpecho/tcpecho.h

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#ifndef __TCPECHO_H__
+#define __TCPECHO_H__
+
+void tcpecho_init(void);
+
+#endif /* __TCPECHO_H__ */

src/lwip-1.4.1/apps/tcpecho_raw/echo.c

@@ -0,0 +1,363 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of and a contribution to the lwIP TCP/IP stack.
+ *
+ * Credits go to Adam Dunkels (and the current maintainers) of this software.
+ *
+ * Christiaan Simons rewrote this file to get a more stable echo example.
+ */
+
+/**
+ * @file
+ * TCP echo server example using raw API.
+ *
+ * Echos all bytes sent by connecting client,
+ * and passively closes when client is done.
+ *
+ */
+
+
+#include "lwip/opt.h"
+#include "lwip/debug.h"
+#include "lwip/stats.h"
+#include "lwip/tcp.h"
+
+#if LWIP_TCP
+
+static struct tcp_pcb *echo_pcb;
+
+enum echo_states
+{
+  ES_NONE = 0,
+  ES_ACCEPTED,
+  ES_RECEIVED,
+  ES_CLOSING
+};
+
+struct echo_state
+{
+  u8_t state;
+  u8_t retries;
+  struct tcp_pcb *pcb;
+  /* pbuf (chain) to recycle */
+  struct pbuf *p;
+};
+
+err_t echo_accept(void *arg, struct tcp_pcb *newpcb, err_t err);
+err_t echo_recv(void *arg, struct tcp_pcb *tpcb, struct pbuf *p, err_t err);
+void echo_error(void *arg, err_t err);
+err_t echo_poll(void *arg, struct tcp_pcb *tpcb);
+err_t echo_sent(void *arg, struct tcp_pcb *tpcb, u16_t len);
+void echo_send(struct tcp_pcb *tpcb, struct echo_state *es);
+void echo_close(struct tcp_pcb *tpcb, struct echo_state *es);
+
+void
+echo_init(void)
+{
+  echo_pcb = tcp_new();
+  if (echo_pcb != NULL)
+  {
+    err_t err;
+
+    err = tcp_bind(echo_pcb, IP_ADDR_ANY, 7);
+    if (err == ERR_OK)
+    {
+      echo_pcb = tcp_listen(echo_pcb);
+      tcp_accept(echo_pcb, echo_accept);
+    }
+    else 
+    {
+      /* abort? output diagnostic? */
+    }
+  }
+  else
+  {
+    /* abort? output diagnostic? */
+  }
+}
+
+
+err_t
+echo_accept(void *arg, struct tcp_pcb *newpcb, err_t err)
+{
+  err_t ret_err;
+  struct echo_state *es;
+
+  LWIP_UNUSED_ARG(arg);
+  LWIP_UNUSED_ARG(err);
+
+  /* Unless this pcb should have NORMAL priority, set its priority now.
+     When running out of pcbs, low priority pcbs can be aborted to create
+     new pcbs of higher priority. */
+  tcp_setprio(newpcb, TCP_PRIO_MIN);
+
+  es = (struct echo_state *)mem_malloc(sizeof(struct echo_state));
+  if (es != NULL)
+  {
+    es->state = ES_ACCEPTED;
+    es->pcb = newpcb;
+    es->retries = 0;
+    es->p = NULL;
+    /* pass newly allocated es to our callbacks */
+    tcp_arg(newpcb, es);
+    tcp_recv(newpcb, echo_recv);
+    tcp_err(newpcb, echo_error);
+    tcp_poll(newpcb, echo_poll, 0);
+    ret_err = ERR_OK;
+  }
+  else
+  {
+    ret_err = ERR_MEM;
+  }
+  return ret_err;  
+}
+
+err_t
+echo_recv(void *arg, struct tcp_pcb *tpcb, struct pbuf *p, err_t err)
+{
+  struct echo_state *es;
+  err_t ret_err;
+
+  LWIP_ASSERT("arg != NULL",arg != NULL);
+  es = (struct echo_state *)arg;
+  if (p == NULL)
+  {
+    /* remote host closed connection */
+    es->state = ES_CLOSING;
+    if(es->p == NULL)
+    {
+       /* we're done sending, close it */
+       echo_close(tpcb, es);
+    }
+    else
+    {
+      /* we're not done yet */
+      tcp_sent(tpcb, echo_sent);
+      echo_send(tpcb, es);
+    }
+    ret_err = ERR_OK;
+  }
+  else if(err != ERR_OK)
+  {
+    /* cleanup, for unkown reason */
+    if (p != NULL)
+    {
+      es->p = NULL;
+      pbuf_free(p);
+    }
+    ret_err = err;
+  }
+  else if(es->state == ES_ACCEPTED)
+  {
+    /* first data chunk in p->payload */
+    es->state = ES_RECEIVED;
+    /* store reference to incoming pbuf (chain) */
+    es->p = p;
+    /* install send completion notifier */
+    tcp_sent(tpcb, echo_sent);
+    echo_send(tpcb, es);
+    ret_err = ERR_OK;
+  }
+  else if (es->state == ES_RECEIVED)
+  {
+    /* read some more data */
+    if(es->p == NULL)
+    {
+      es->p = p;
+      tcp_sent(tpcb, echo_sent);
+      echo_send(tpcb, es);
+    }
+    else
+    {
+      struct pbuf *ptr;
+
+      /* chain pbufs to the end of what we recv'ed previously  */
+      ptr = es->p;
+      pbuf_chain(ptr,p);
+    }
+    ret_err = ERR_OK;
+  }
+  else if(es->state == ES_CLOSING)
+  {
+    /* odd case, remote side closing twice, trash data */
+    tcp_recved(tpcb, p->tot_len);
+    es->p = NULL;
+    pbuf_free(p);
+    ret_err = ERR_OK;
+  }
+  else
+  {
+    /* unkown es->state, trash data  */
+    tcp_recved(tpcb, p->tot_len);
+    es->p = NULL;
+    pbuf_free(p);
+    ret_err = ERR_OK;
+  }
+  return ret_err;
+}
+
+void
+echo_error(void *arg, err_t err)
+{
+  struct echo_state *es;
+
+  LWIP_UNUSED_ARG(err);
+
+  es = (struct echo_state *)arg;
+  if (es != NULL)
+  {
+    mem_free(es);
+  }
+}
+
+err_t
+echo_poll(void *arg, struct tcp_pcb *tpcb)
+{
+  err_t ret_err;
+  struct echo_state *es;
+
+  es = (struct echo_state *)arg;
+  if (es != NULL)
+  {
+    if (es->p != NULL)
+    {
+      /* there is a remaining pbuf (chain)  */
+      tcp_sent(tpcb, echo_sent);
+      echo_send(tpcb, es);
+    }
+    else
+    {
+      /* no remaining pbuf (chain)  */
+      if(es->state == ES_CLOSING)
+      {
+        echo_close(tpcb, es);
+      }
+    }
+    ret_err = ERR_OK;
+  }
+  else
+  {
+    /* nothing to be done */
+    tcp_abort(tpcb);
+    ret_err = ERR_ABRT;
+  }
+  return ret_err;
+}
+
+err_t
+echo_sent(void *arg, struct tcp_pcb *tpcb, u16_t len)
+{
+  struct echo_state *es;
+
+  LWIP_UNUSED_ARG(len);
+
+  es = (struct echo_state *)arg;
+  es->retries = 0;
+  
+  if(es->p != NULL)
+  {
+    /* still got pbufs to send */
+    tcp_sent(tpcb, echo_sent);
+    echo_send(tpcb, es);
+  }
+  else
+  {
+    /* no more pbufs to send */
+    if(es->state == ES_CLOSING)
+    {
+      echo_close(tpcb, es);
+    }
+  }
+  return ERR_OK;
+}
+
+void
+echo_send(struct tcp_pcb *tpcb, struct echo_state *es)
+{
+  struct pbuf *ptr;
+  err_t wr_err = ERR_OK;
+ 
+  while ((wr_err == ERR_OK) &&
+         (es->p != NULL) && 
+         (es->p->len <= tcp_sndbuf(tpcb)))
+  {
+  ptr = es->p;
+
+  /* enqueue data for transmission */
+  wr_err = tcp_write(tpcb, ptr->payload, ptr->len, 1);
+  if (wr_err == ERR_OK)
+  {
+     u16_t plen;
+      u8_t freed;
+
+     plen = ptr->len;
+     /* continue with next pbuf in chain (if any) */
+     es->p = ptr->next;
+     if(es->p != NULL)
+     {
+       /* new reference! */
+       pbuf_ref(es->p);
+     }
+     /* chop first pbuf from chain */
+      do
+      {
+        /* try hard to free pbuf */
+        freed = pbuf_free(ptr);
+      }
+      while(freed == 0);
+     /* we can read more data now */
+     tcp_recved(tpcb, plen);
+   }
+   else if(wr_err == ERR_MEM)
+   {
+      /* we are low on memory, try later / harder, defer to poll */
+     es->p = ptr;
+   }
+   else
+   {
+     /* other problem ?? */
+   }
+  }
+}
+
+void
+echo_close(struct tcp_pcb *tpcb, struct echo_state *es)
+{
+  tcp_arg(tpcb, NULL);
+  tcp_sent(tpcb, NULL);
+  tcp_recv(tpcb, NULL);
+  tcp_err(tpcb, NULL);
+  tcp_poll(tpcb, NULL, 0);
+  
+  if (es != NULL)
+  {
+    mem_free(es);
+  }  
+  tcp_close(tpcb);
+}
+
+#endif /* LWIP_TCP */

src/lwip-1.4.1/apps/tcpecho_raw/echo.h

@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ */
+#ifndef __ECHO_H__
+#define __ECHO_H__
+
+void echo_init(void);
+
+#endif /* __MINIMAL_ECHO_H */

src/lwip-1.4.1/apps/udpecho/udpecho.c

@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "udpecho.h"
+
+#include "lwip/opt.h"
+
+#if LWIP_NETCONN
+
+#include "lwip/api.h"
+#include "lwip/sys.h"
+
+/*-----------------------------------------------------------------------------------*/
+static void
+udpecho_thread(void *arg)
+{
+  static struct netconn *conn;
+  static struct netbuf *buf;
+  static ip_addr_t *addr;
+  static unsigned short port;
+  char buffer[4096];
+  err_t err;
+  LWIP_UNUSED_ARG(arg);
+
+  conn = netconn_new(NETCONN_UDP);
+  LWIP_ASSERT("con != NULL", conn != NULL);
+  netconn_bind(conn, NULL, 7);
+
+  while (1) {
+    err = netconn_recv(conn, &buf);
+    if (err == ERR_OK) {
+      addr = netbuf_fromaddr(buf);
+      port = netbuf_fromport(buf);
+      /*  no need netconn_connect here, since the netbuf contains the address */
+      if(netbuf_copy(buf, buffer, buf->p->tot_len) != buf->p->tot_len) {
+        LWIP_DEBUGF(LWIP_DBG_ON, ("netbuf_copy failed\n"));
+      } else {
+        buffer[buf->p->tot_len] = '\0';
+        err = netconn_send(conn, buf);
+        if(err != ERR_OK) {
+          LWIP_DEBUGF(LWIP_DBG_ON, ("netconn_send failed: %d\n", (int)err));
+        } else {
+          LWIP_DEBUGF(LWIP_DBG_ON, ("got %s\n", buffer));
+        }
+      }
+      netbuf_delete(buf);
+    }
+  }
+}
+/*-----------------------------------------------------------------------------------*/
+void
+udpecho_init(void)
+{
+  sys_thread_new("udpecho_thread", udpecho_thread, NULL, DEFAULT_THREAD_STACKSIZE, DEFAULT_THREAD_PRIO);
+}
+
+#endif /* LWIP_NETCONN */

src/lwip-1.4.1/apps/udpecho/udpecho.h

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __UDPECHO_H__
+#define __UDPECHO_H__
+
+void udpecho_init(void);
+
+#endif /* __UDPECHO_H__ */

src/lwip-1.4.1/doc/FILES

@@ -0,0 +1,6 @@
+savannah.txt   - How to obtain the current development source code.
+contrib.txt    - How to contribute to lwIP as a developer.
+rawapi.txt     - The documentation for the core API of lwIP.
+                 Also provides an overview about the other APIs and multithreading.
+snmp_agent.txt - The documentation for the lwIP SNMP agent.
+sys_arch.txt   - The documentation for a system abstraction layer of lwIP.

src/lwip-1.4.1/doc/contrib.txt

@@ -0,0 +1,63 @@
+1 Introduction
+
+This document describes some guidelines for people participating
+in lwIP development.
+
+2 How to contribute to lwIP
+
+Here is a short list of suggestions to anybody working with lwIP and 
+trying to contribute bug reports, fixes, enhancements, platform ports etc.
+First of all as you may already know lwIP is a volunteer project so feedback
+to fixes or questions might often come late. Hopefully the bug and patch tracking 
+features of Savannah help us not lose users' input.
+
+2.1 Source code style:
+
+1. do not use tabs.
+2. indentation is two spaces per level (i.e. per tab).
+3. end debug messages with a trailing newline (\n).
+4. one space between keyword and opening bracket.
+5. no space between function and opening bracket.
+6. one space and no newline before opening curly braces of a block.
+7. closing curly brace on a single line.
+8. spaces surrounding assignment and comparisons.
+9. don't initialize static and/or global variables to zero, the compiler takes care of that.
+10. use current source code style as further reference.
+
+2.2 Source code documentation style:
+
+1. JavaDoc compliant and Doxygen compatible.
+2. Function documentation above functions in .c files, not .h files.
+   (This forces you to synchronize documentation and implementation.)
+3. Use current documentation style as further reference.
+ 
+2.3 Bug reports and patches:
+
+1. Make sure you are reporting bugs or send patches against the latest
+   sources. (From the latest release and/or the current CVS sources.)
+2. If you think you found a bug make sure it's not already filed in the
+   bugtracker at Savannah.
+3. If you have a fix put the patch on Savannah. If it is a patch that affects
+   both core and arch specific stuff please separate them so that the core can
+   be applied separately while leaving the other patch 'open'. The prefered way
+   is to NOT touch archs you can't test and let maintainers take care of them.
+   This is a good way to see if they are used at all - the same goes for unix
+   netifs except tapif.
+4. Do not file a bug and post a fix to it to the patch area. Either a bug report
+   or a patch will be enough.
+   If you correct an existing bug then attach the patch to the bug rather than creating a new entry in the patch area.
+5. Trivial patches (compiler warning, indentation and spelling fixes or anything obvious which takes a line or two)
+   can go to the lwip-users list. This is still the fastest way of interaction and the list is not so crowded
+   as to allow for loss of fixes. Putting bugs on Savannah and subsequently closing them is too much an overhead
+   for reporting a compiler warning fix.
+6. Patches should be specific to a single change or to related changes.Do not mix bugfixes with spelling and other
+   trivial fixes unless the bugfix is trivial too.Do not reorganize code and rename identifiers in the same patch you
+   change behaviour if not necessary.A patch is easier to read and understand if it's to the point and short than
+   if it's not to the point and long :) so the chances for it to be applied are greater. 
+
+2.4 Platform porters:
+
+1. If you have ported lwIP to a platform (an OS, a uC/processor or a combination of these) and
+   you think it could benefit others[1] you might want discuss this on the mailing list. You
+   can also ask for CVS access to submit and maintain your port in the contrib CVS module.
+   

src/lwip-1.4.1/doc/rawapi.txt

@@ -0,0 +1,511 @@
+Raw TCP/IP interface for lwIP
+
+Authors: Adam Dunkels, Leon Woestenberg, Christiaan Simons
+
+lwIP provides three Application Program's Interfaces (APIs) for programs
+to use for communication with the TCP/IP code:
+* low-level "core" / "callback" or "raw" API.
+* higher-level "sequential" API.
+* BSD-style socket API.
+
+The sequential API provides a way for ordinary, sequential, programs
+to use the lwIP stack. It is quite similar to the BSD socket API. The
+model of execution is based on the blocking open-read-write-close
+paradigm. Since the TCP/IP stack is event based by nature, the TCP/IP
+code and the application program must reside in different execution
+contexts (threads).
+
+The socket API is a compatibility API for existing applications,
+currently it is built on top of the sequential API. It is meant to
+provide all functions needed to run socket API applications running
+on other platforms (e.g. unix / windows etc.). However, due to limitations
+in the specification of this API, there might be incompatibilities
+that require small modifications of existing programs.
+
+** Threading
+
+lwIP started targeting single-threaded environments. When adding multi-
+threading support, instead of making the core thread-safe, another
+approach was chosen: there is one main thread running the lwIP core
+(also known as the "tcpip_thread"). The raw API may only be used from
+this thread! Application threads using the sequential- or socket API
+communicate with this main thread through message passing.
+
+      As such, the list of functions that may be called from
+      other threads or an ISR is very limited! Only functions
+      from these API header files are thread-safe:
+      - api.h
+      - netbuf.h
+      - netdb.h
+      - netifapi.h
+      - sockets.h
+      - sys.h
+
+      Additionaly, memory (de-)allocation functions may be
+      called from multiple threads (not ISR!) with NO_SYS=0
+      since they are protected by SYS_LIGHTWEIGHT_PROT and/or
+      semaphores.
+
+      Only since 1.3.0, if SYS_LIGHTWEIGHT_PROT is set to 1
+      and LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT is set to 1,
+      pbuf_free() may also be called from another thread or
+      an ISR (since only then, mem_free - for PBUF_RAM - may
+      be called from an ISR: otherwise, the HEAP is only
+      protected by semaphores).
+      
+
+** The remainder of this document discusses the "raw" API. **
+
+The raw TCP/IP interface allows the application program to integrate
+better with the TCP/IP code. Program execution is event based by
+having callback functions being called from within the TCP/IP
+code. The TCP/IP code and the application program both run in the same
+thread. The sequential API has a much higher overhead and is not very
+well suited for small systems since it forces a multithreaded paradigm
+on the application.
+
+The raw TCP/IP interface is not only faster in terms of code execution
+time but is also less memory intensive. The drawback is that program
+development is somewhat harder and application programs written for
+the raw TCP/IP interface are more difficult to understand. Still, this
+is the preferred way of writing applications that should be small in
+code size and memory usage.
+
+Both APIs can be used simultaneously by different application
+programs. In fact, the sequential API is implemented as an application
+program using the raw TCP/IP interface.
+
+--- Callbacks
+
+Program execution is driven by callbacks. Each callback is an ordinary
+C function that is called from within the TCP/IP code. Every callback
+function is passed the current TCP or UDP connection state as an
+argument. Also, in order to be able to keep program specific state,
+the callback functions are called with a program specified argument
+that is independent of the TCP/IP state.
+
+The function for setting the application connection state is:
+
+- void tcp_arg(struct tcp_pcb *pcb, void *arg)
+
+  Specifies the program specific state that should be passed to all
+  other callback functions. The "pcb" argument is the current TCP
+  connection control block, and the "arg" argument is the argument
+  that will be passed to the callbacks.
+
+  
+--- TCP connection setup
+
+The functions used for setting up connections is similar to that of
+the sequential API and of the BSD socket API. A new TCP connection
+identifier (i.e., a protocol control block - PCB) is created with the
+tcp_new() function. This PCB can then be either set to listen for new
+incoming connections or be explicitly connected to another host.
+
+- struct tcp_pcb *tcp_new(void)
+
+  Creates a new connection identifier (PCB). If memory is not
+  available for creating the new pcb, NULL is returned.
+
+- err_t tcp_bind(struct tcp_pcb *pcb, ip_addr_t *ipaddr,
+                 u16_t port)
+
+  Binds the pcb to a local IP address and port number. The IP address
+  can be specified as IP_ADDR_ANY in order to bind the connection to
+  all local IP addresses.
+
+  If another connection is bound to the same port, the function will
+  return ERR_USE, otherwise ERR_OK is returned.
+
+- struct tcp_pcb *tcp_listen(struct tcp_pcb *pcb)
+
+  Commands a pcb to start listening for incoming connections. When an
+  incoming connection is accepted, the function specified with the
+  tcp_accept() function will be called. The pcb will have to be bound
+  to a local port with the tcp_bind() function.
+
+  The tcp_listen() function returns a new connection identifier, and
+  the one passed as an argument to the function will be
+  deallocated. The reason for this behavior is that less memory is
+  needed for a connection that is listening, so tcp_listen() will
+  reclaim the memory needed for the original connection and allocate a
+  new smaller memory block for the listening connection.
+
+  tcp_listen() may return NULL if no memory was available for the
+  listening connection. If so, the memory associated with the pcb
+  passed as an argument to tcp_listen() will not be deallocated.
+
+- struct tcp_pcb *tcp_listen_with_backlog(struct tcp_pcb *pcb, u8_t backlog)
+
+  Same as tcp_listen, but limits the number of outstanding connections
+  in the listen queue to the value specified by the backlog argument.
+  To use it, your need to set TCP_LISTEN_BACKLOG=1 in your lwipopts.h.
+
+- void tcp_accepted(struct tcp_pcb *pcb)
+
+  Inform lwIP that an incoming connection has been accepted. This would
+  usually be called from the accept callback. This allows lwIP to perform
+  housekeeping tasks, such as allowing further incoming connections to be
+  queued in the listen backlog.
+  ATTENTION: the PCB passed in must be the listening pcb, not the pcb passed
+  into the accept callback!
+
+- void tcp_accept(struct tcp_pcb *pcb,
+                  err_t (* accept)(void *arg, struct tcp_pcb *newpcb,
+                                   err_t err))
+
+  Specified the callback function that should be called when a new
+  connection arrives on a listening connection.
+
+- err_t tcp_connect(struct tcp_pcb *pcb, ip_addr_t *ipaddr,
+                    u16_t port, err_t (* connected)(void *arg,
+                                                    struct tcp_pcb *tpcb,
+                                                    err_t err));
+
+  Sets up the pcb to connect to the remote host and sends the
+  initial SYN segment which opens the connection. 
+
+  The tcp_connect() function returns immediately; it does not wait for
+  the connection to be properly setup. Instead, it will call the
+  function specified as the fourth argument (the "connected" argument)
+  when the connection is established. If the connection could not be
+  properly established, either because the other host refused the
+  connection or because the other host didn't answer, the "err"
+  callback function of this pcb (registered with tcp_err, see below)
+  will be called.
+
+  The tcp_connect() function can return ERR_MEM if no memory is
+  available for enqueueing the SYN segment. If the SYN indeed was
+  enqueued successfully, the tcp_connect() function returns ERR_OK.
+
+
+--- Sending TCP data
+
+TCP data is sent by enqueueing the data with a call to
+tcp_write(). When the data is successfully transmitted to the remote
+host, the application will be notified with a call to a specified
+callback function.
+
+- err_t tcp_write(struct tcp_pcb *pcb, const void *dataptr, u16_t len,
+                  u8_t apiflags)
+
+  Enqueues the data pointed to by the argument dataptr. The length of
+  the data is passed as the len parameter. The apiflags can be one or more of:
+  - TCP_WRITE_FLAG_COPY: indicates whether the new memory should be allocated
+    for the data to be copied into. If this flag is not given, no new memory
+    should be allocated and the data should only be referenced by pointer. This
+    also means that the memory behind dataptr must not change until the data is
+    ACKed by the remote host
+  - TCP_WRITE_FLAG_MORE: indicates that more data follows. If this is given,
+    the PSH flag is set in the last segment created by this call to tcp_write.
+    If this flag is given, the PSH flag is not set.
+
+  The tcp_write() function will fail and return ERR_MEM if the length
+  of the data exceeds the current send buffer size or if the length of
+  the queue of outgoing segment is larger than the upper limit defined
+  in lwipopts.h. The number of bytes available in the output queue can
+  be retrieved with the tcp_sndbuf() function.
+
+  The proper way to use this function is to call the function with at
+  most tcp_sndbuf() bytes of data. If the function returns ERR_MEM,
+  the application should wait until some of the currently enqueued
+  data has been successfully received by the other host and try again.
+
+- void tcp_sent(struct tcp_pcb *pcb,
+                err_t (* sent)(void *arg, struct tcp_pcb *tpcb,
+                u16_t len))
+
+  Specifies the callback function that should be called when data has
+  successfully been received (i.e., acknowledged) by the remote
+  host. The len argument passed to the callback function gives the
+  amount bytes that was acknowledged by the last acknowledgment.
+
+  
+--- Receiving TCP data
+
+TCP data reception is callback based - an application specified
+callback function is called when new data arrives. When the
+application has taken the data, it has to call the tcp_recved()
+function to indicate that TCP can advertise increase the receive
+window.
+
+- void tcp_recv(struct tcp_pcb *pcb,
+                err_t (* recv)(void *arg, struct tcp_pcb *tpcb,
+                               struct pbuf *p, err_t err))
+
+  Sets the callback function that will be called when new data
+  arrives. The callback function will be passed a NULL pbuf to
+  indicate that the remote host has closed the connection. If
+  there are no errors and the callback function is to return
+  ERR_OK, then it must free the pbuf. Otherwise, it must not
+  free the pbuf so that lwIP core code can store it.
+
+- void tcp_recved(struct tcp_pcb *pcb, u16_t len)
+
+  Must be called when the application has received the data. The len
+  argument indicates the length of the received data.
+
+
+--- Application polling
+
+When a connection is idle (i.e., no data is either transmitted or
+received), lwIP will repeatedly poll the application by calling a
+specified callback function. This can be used either as a watchdog
+timer for killing connections that have stayed idle for too long, or
+as a method of waiting for memory to become available. For instance,
+if a call to tcp_write() has failed because memory wasn't available,
+the application may use the polling functionality to call tcp_write()
+again when the connection has been idle for a while.
+
+- void tcp_poll(struct tcp_pcb *pcb, 
+                err_t (* poll)(void *arg, struct tcp_pcb *tpcb),
+                u8_t interval)
+
+  Specifies the polling interval and the callback function that should
+  be called to poll the application. The interval is specified in
+  number of TCP coarse grained timer shots, which typically occurs
+  twice a second. An interval of 10 means that the application would
+  be polled every 5 seconds.
+
+
+--- Closing and aborting connections
+
+- err_t tcp_close(struct tcp_pcb *pcb)
+
+  Closes the connection. The function may return ERR_MEM if no memory
+  was available for closing the connection. If so, the application
+  should wait and try again either by using the acknowledgment
+  callback or the polling functionality. If the close succeeds, the
+  function returns ERR_OK.
+
+  The pcb is deallocated by the TCP code after a call to tcp_close(). 
+
+- void tcp_abort(struct tcp_pcb *pcb)
+
+  Aborts the connection by sending a RST (reset) segment to the remote
+  host. The pcb is deallocated. This function never fails.
+
+  ATTENTION: When calling this from one of the TCP callbacks, make
+  sure you always return ERR_ABRT (and never return ERR_ABRT otherwise
+  or you will risk accessing deallocated memory or memory leaks!
+
+
+If a connection is aborted because of an error, the application is
+alerted of this event by the err callback. Errors that might abort a
+connection are when there is a shortage of memory. The callback
+function to be called is set using the tcp_err() function.
+
+- void tcp_err(struct tcp_pcb *pcb, void (* err)(void *arg,
+       err_t err))
+
+  The error callback function does not get the pcb passed to it as a
+  parameter since the pcb may already have been deallocated.
+
+
+--- Lower layer TCP interface
+
+TCP provides a simple interface to the lower layers of the
+system. During system initialization, the function tcp_init() has
+to be called before any other TCP function is called. When the system
+is running, the two timer functions tcp_fasttmr() and tcp_slowtmr()
+must be called with regular intervals. The tcp_fasttmr() should be
+called every TCP_FAST_INTERVAL milliseconds (defined in tcp.h) and
+tcp_slowtmr() should be called every TCP_SLOW_INTERVAL milliseconds. 
+
+
+--- UDP interface
+
+The UDP interface is similar to that of TCP, but due to the lower
+level of complexity of UDP, the interface is significantly simpler.
+
+- struct udp_pcb *udp_new(void)
+
+  Creates a new UDP pcb which can be used for UDP communication. The
+  pcb is not active until it has either been bound to a local address
+  or connected to a remote address.
+
+- void udp_remove(struct udp_pcb *pcb)
+
+  Removes and deallocates the pcb.  
+  
+- err_t udp_bind(struct udp_pcb *pcb, ip_addr_t *ipaddr,
+                 u16_t port)
+
+  Binds the pcb to a local address. The IP-address argument "ipaddr"
+  can be IP_ADDR_ANY to indicate that it should listen to any local IP
+  address. The function currently always return ERR_OK.
+
+- err_t udp_connect(struct udp_pcb *pcb, ip_addr_t *ipaddr,
+                    u16_t port)
+
+  Sets the remote end of the pcb. This function does not generate any
+  network traffic, but only set the remote address of the pcb.
+
+- err_t udp_disconnect(struct udp_pcb *pcb)
+
+  Remove the remote end of the pcb. This function does not generate
+  any network traffic, but only removes the remote address of the pcb.
+
+- err_t udp_send(struct udp_pcb *pcb, struct pbuf *p)
+
+  Sends the pbuf p. The pbuf is not deallocated.
+
+- void udp_recv(struct udp_pcb *pcb,
+                void (* recv)(void *arg, struct udp_pcb *upcb,
+                                         struct pbuf *p,
+                                         ip_addr_t *addr,
+                                         u16_t port),
+                              void *recv_arg)
+
+  Specifies a callback function that should be called when a UDP
+  datagram is received.
+  
+
+--- System initalization
+
+A truly complete and generic sequence for initializing the lwip stack
+cannot be given because it depends on the build configuration (lwipopts.h)
+and additional initializations for your runtime environment (e.g. timers).
+
+We can give you some idea on how to proceed when using the raw API.
+We assume a configuration using a single Ethernet netif and the
+UDP and TCP transport layers, IPv4 and the DHCP client.
+
+Call these functions in the order of appearance:
+
+- stats_init()
+
+  Clears the structure where runtime statistics are gathered.
+
+- sys_init()
+  
+  Not of much use since we set the NO_SYS 1 option in lwipopts.h,
+  to be called for easy configuration changes.
+
+- mem_init()
+
+  Initializes the dynamic memory heap defined by MEM_SIZE.
+
+- memp_init()
+
+  Initializes the memory pools defined by MEMP_NUM_x.
+
+- pbuf_init()
+
+  Initializes the pbuf memory pool defined by PBUF_POOL_SIZE.
+  
+- etharp_init()
+
+  Initializes the ARP table and queue.
+  Note: you must call etharp_tmr at a ARP_TMR_INTERVAL (5 seconds) regular interval
+  after this initialization.
+
+- ip_init()
+
+  Doesn't do much, it should be called to handle future changes.
+
+- udp_init()
+
+  Clears the UDP PCB list.
+
+- tcp_init()
+
+  Clears the TCP PCB list and clears some internal TCP timers.
+  Note: you must call tcp_fasttmr() and tcp_slowtmr() at the
+  predefined regular intervals after this initialization. 
+  
+- netif_add(struct netif *netif, ip_addr_t *ipaddr,
+            ip_addr_t *netmask, ip_addr_t *gw,
+            void *state, err_t (* init)(struct netif *netif),
+            err_t (* input)(struct pbuf *p, struct netif *netif))
+
+  Adds your network interface to the netif_list. Allocate a struct
+  netif and pass a pointer to this structure as the first argument.
+  Give pointers to cleared ip_addr structures when using DHCP,
+  or fill them with sane numbers otherwise. The state pointer may be NULL.
+
+  The init function pointer must point to a initialization function for
+  your ethernet netif interface. The following code illustrates it's use.
+  
+  err_t netif_if_init(struct netif *netif)
+  {
+    u8_t i;
+    
+    for(i = 0; i < ETHARP_HWADDR_LEN; i++) netif->hwaddr[i] = some_eth_addr[i];
+    init_my_eth_device();
+    return ERR_OK;
+  }
+  
+  For ethernet drivers, the input function pointer must point to the lwip
+  function ethernet_input() declared in "netif/etharp.h". Other drivers
+  must use ip_input() declared in "lwip/ip.h".
+  
+- netif_set_default(struct netif *netif)
+
+  Registers the default network interface.
+
+- netif_set_up(struct netif *netif)
+
+  When the netif is fully configured this function must be called.
+
+- dhcp_start(struct netif *netif)
+
+  Creates a new DHCP client for this interface on the first call.
+  Note: you must call dhcp_fine_tmr() and dhcp_coarse_tmr() at
+  the predefined regular intervals after starting the client.
+  
+  You can peek in the netif->dhcp struct for the actual DHCP status.
+
+
+--- Optimalization hints
+
+The first thing you want to optimize is the lwip_standard_checksum()
+routine from src/core/inet.c. You can override this standard
+function with the #define LWIP_CHKSUM <your_checksum_routine>.
+
+There are C examples given in inet.c or you might want to
+craft an assembly function for this. RFC1071 is a good
+introduction to this subject.
+
+Other significant improvements can be made by supplying
+assembly or inline replacements for htons() and htonl()
+if you're using a little-endian architecture.
+#define LWIP_PLATFORM_BYTESWAP 1
+#define LWIP_PLATFORM_HTONS(x) <your_htons>
+#define LWIP_PLATFORM_HTONL(x) <your_htonl>
+
+Check your network interface driver if it reads at
+a higher speed than the maximum wire-speed. If the
+hardware isn't serviced frequently and fast enough
+buffer overflows are likely to occur.
+
+E.g. when using the cs8900 driver, call cs8900if_service(ethif)
+as frequently as possible. When using an RTOS let the cs8900 interrupt
+wake a high priority task that services your driver using a binary
+semaphore or event flag. Some drivers might allow additional tuning
+to match your application and network.
+
+For a production release it is recommended to set LWIP_STATS to 0.
+Note that speed performance isn't influenced much by simply setting
+high values to the memory options.
+
+For more optimization hints take a look at the lwIP wiki.
+
+--- Zero-copy MACs
+
+To achieve zero-copy on transmit, the data passed to the raw API must
+remain unchanged until sent. Because the send- (or write-)functions return
+when the packets have been enqueued for sending, data must be kept stable
+after that, too.
+
+This implies that PBUF_RAM/PBUF_POOL pbufs passed to raw-API send functions
+must *not* be reused by the application unless their ref-count is 1.
+
+For no-copy pbufs (PBUF_ROM/PBUF_REF), data must be kept unchanged, too,
+but the stack/driver will/must copy PBUF_REF'ed data when enqueueing, while
+PBUF_ROM-pbufs are just enqueued (as ROM-data is expected to never change).
+
+Also, data passed to tcp_write without the copy-flag must not be changed!
+
+Therefore, be careful which type of PBUF you use and if you copy TCP data
+or not!

src/lwip-1.4.1/doc/savannah.txt

@@ -0,0 +1,135 @@
+Daily Use Guide for using Savannah for lwIP
+
+Table of Contents:
+
+1 - Obtaining lwIP from the CVS repository
+2 - Committers/developers CVS access using SSH (to be written)
+3 - Merging from DEVEL branch to main trunk (stable branch)
+4 - How to release lwIP
+
+
+
+1 Obtaining lwIP from the CVS repository
+----------------------------------------
+
+To perform an anonymous CVS checkout of the main trunk (this is where
+bug fixes and incremental enhancements occur), do this:
+
+cvs -z3 -d:pserver:anonymous@cvs.sv.gnu.org:/sources/lwip checkout lwip
+ 
+Or, obtain a stable branch (updated with bug fixes only) as follows:
+cvs -z3 -d:pserver:anonymous@cvs.sv.gnu.org:/sources/lwip checkout \
+  -r STABLE-0_7 -d lwip-0.7 lwip
+
+Or, obtain a specific (fixed) release as follows:
+cvs -z3 -d:pserver:anonymous@cvs.sv.gnu.org:/sources/lwip checkout \
+  -r STABLE-0_7_0 -d lwip-0.7.0 lwip
+
+3 Committers/developers CVS access using SSH
+--------------------------------------------
+
+The Savannah server uses SSH (Secure Shell) protocol 2 authentication and encryption.
+As such, CVS commits to the server occur through a SSH tunnel for project members.
+To create a SSH2 key pair in UNIX-like environments, do this:
+
+ssh-keygen -t dsa
+
+Under Windows, a recommended SSH client is "PuTTY", freely available with good
+documentation and a graphic user interface. Use its key generator.
+
+Now paste the id_dsa.pub contents into your Savannah account public key list. Wait
+a while so that Savannah can update its configuration (This can take minutes).
+
+Try to login using SSH:
+
+ssh -v your_login@cvs.sv.gnu.org
+
+If it tells you:
+
+Authenticating with public key "your_key_name"...
+Server refused to allocate pty
+
+then you could login; Savannah refuses to give you a shell - which is OK, as we
+are allowed to use SSH for CVS only. Now, you should be able to do this:
+
+export CVS_RSH=ssh
+cvs -z3 -d:ext:your_login@cvs.sv.gnu.org:/sources/lwip co lwip
+ 
+after which you can edit your local files with bug fixes or new features and
+commit them. Make sure you know what you are doing when using CVS to make
+changes on the repository. If in doubt, ask on the lwip-members mailing list.
+
+(If SSH asks about authenticity of the host, you can check the key
+ fingerprint against http://savannah.nongnu.org/cvs/?group=lwip)
+
+
+3 Merging from DEVEL branch to main trunk (stable)
+--------------------------------------------------
+
+Merging is a delicate process in CVS and requires the
+following disciplined steps in order to prevent conflicts
+in the future. Conflicts can be hard to solve!
+
+Merging from branch A to branch B requires that the A branch
+has a tag indicating the previous merger. This tag is called
+'merged_from_A_to_B'. After merging, the tag is moved in the
+A branch to remember this merger for future merge actions.
+
+IMPORTANT: AFTER COMMITTING A SUCCESFUL MERGE IN THE
+REPOSITORY, THE TAG MUST BE SET ON THE SOURCE BRANCH OF THE
+MERGE ACTION (REPLACING EXISTING TAGS WITH THE SAME NAME).
+
+Merge all changes in DEVEL since our last merge to main:
+
+In the working copy of the main trunk:
+cvs update -P -jmerged_from_DEVEL_to_main -jDEVEL 
+
+(This will apply the changes between 'merged_from_DEVEL_to_main'
+and 'DEVEL' to your work set of files)
+
+We can now commit the merge result.
+cvs commit -R -m "Merged from DEVEL to main." 
+
+If this worked out OK, we now move the tag in the DEVEL branch
+to this merge point, so we can use this point for future merges:
+
+cvs rtag -F -r DEVEL merged_from_DEVEL_to_main lwip 
+
+4 How to release lwIP
+---------------------
+
+First, checkout a clean copy of the branch to be released. Tag this set with
+tag name "STABLE-0_6_3". (I use release number 0.6.3 throughout this example).
+
+Login CVS using pserver authentication, then export a clean copy of the
+tagged tree. Export is similar to a checkout, except that the CVS metadata
+is not created locally. 
+
+export CVS_RSH=ssh
+cvs -z3 -d:pserver:anonymous@cvs.sv.gnu.org:/sources/lwip checkout \
+  -r STABLE-0_6_3 -d lwip-0.6.3 lwip
+
+Archive this directory using tar, gzip'd, bzip2'd and zip'd.
+
+tar czvf lwip-0.6.3.tar.gz lwip-0.6.3
+tar cjvf lwip-0.6.3.tar.bz2 lwip-0.6.3
+zip -r lwip-0.6.3.zip lwip-0.6.3
+
+Now, sign the archives with a detached GPG binary signature as follows:
+
+gpg -b lwip-0.6.3.tar.gz
+gpg -b lwip-0.6.3.tar.bz2
+gpg -b lwip-0.6.3.zip
+
+Upload these files using anonymous FTP:
+ncftp ftp://savannah.gnu.org/incoming/savannah/lwip
+
+ncftp>mput *0.6.3.*
+
+Additionally, you may post a news item on Savannah, like this:
+
+A new 0.6.3 release is now available here:
+http://savannah.nongnu.org/files/?group=lwip&highlight=0.6.3
+
+You will have to submit this via the user News interface, then approve
+this via the Administrator News interface.

src/lwip-1.4.1/doc/snmp_agent.txt

@@ -0,0 +1,181 @@
+SNMPv1 agent for lwIP
+
+Author: Christiaan Simons
+
+This is a brief introduction how to use and configure the SNMP agent.
+Note the agent uses the raw-API UDP interface so you may also want to
+read rawapi.txt to gain a better understanding of the SNMP message handling.
+
+0 Agent Capabilities
+====================
+
+SNMPv1 per RFC1157
+  This is an old(er) standard but is still widely supported.
+  For SNMPv2c and v3 have a greater complexity and need many
+  more lines of code. IMHO this breaks the idea of "lightweight IP".
+
+  Note the S in SNMP stands for "Simple". Note that "Simple" is
+  relative. SNMP is simple compared to the complex ISO network
+  management protocols CMIP (Common Management Information Protocol)
+  and CMOT (CMip Over Tcp).
+
+MIB II per RFC1213
+  The standard lwIP stack management information base.
+  This is a required MIB, so this is always enabled.
+  When builing lwIP without TCP, the mib-2.tcp group is omitted.
+  The groups EGP, CMOT and transmission are disabled by default.
+  
+  Most mib-2 objects are not writable except:
+  sysName, sysLocation, sysContact, snmpEnableAuthenTraps.
+  Writing to or changing the ARP and IP address and route
+  tables is not possible.
+ 
+  Note lwIP has a very limited notion of IP routing. It currently
+  doen't have a route table and doesn't have a notion of the U,G,H flags.
+  Instead lwIP uses the interface list with only one default interface
+  acting as a single gateway interface (G) for the default route.
+
+  The agent returns a "virtual table" with the default route 0.0.0.0
+  for the default interface and network routes (no H) for each
+  network interface in the netif_list.
+  All routes are considered to be up (U).
+
+Loading additional MIBs
+  MIBs can only be added in compile-time, not in run-time.
+  There is no MIB compiler thus additional MIBs must be hand coded.
+
+Large SNMP message support
+  The packet decoding and encoding routines are designed
+  to use pbuf-chains. Larger payloads than the minimum
+  SNMP requirement of 484 octets are supported if the 
+  PBUF_POOL_SIZE and IP_REASS_BUFSIZE are set to match your
+  local requirement.
+
+1 Building the Agent
+====================
+
+First of all you'll need to add the following define
+to your local lwipopts.h:
+
+#define LWIP_SNMP               1
+
+and add the source files in lwip/src/core/snmp
+and some snmp headers in lwip/src/include/lwip to your makefile.
+
+Note you'll might need to adapt you network driver to update
+the mib2 variables for your interface.
+
+2 Running the Agent
+===================
+
+The following function calls must be made in your program to
+actually get the SNMP agent running.
+
+Before starting the agent you should supply pointers
+to non-volatile memory for sysContact, sysLocation,
+and snmpEnableAuthenTraps. You can do this by calling
+
+snmp_set_syscontact()
+snmp_set_syslocation()
+snmp_set_snmpenableauthentraps()
+
+Additionally you may want to set
+
+snmp_set_sysdescr()
+snmp_set_sysobjid() (if you have a private MIB)
+snmp_set_sysname()
+
+Also before starting the agent you need to setup
+one or more trap destinations using these calls:
+
+snmp_trap_dst_enable();
+snmp_trap_dst_ip_set();
+
+In the lwIP initialisation sequence call snmp_init() just after
+the call to udp_init().
+
+Exactly every 10 msec the SNMP uptime timestamp must be updated with
+snmp_inc_sysuptime(). You should call this from a timer interrupt
+or a timer signal handler depending on your runtime environment.
+
+An alternative way to update the SNMP uptime timestamp is to do a call like
+snmp_add_sysuptime(100) each 1000ms (which is bigger "step", but call to
+a lower frequency). Another one is to not call snmp_inc_sysuptime() or
+snmp_add_sysuptime(), and to define the SNMP_GET_SYSUPTIME(sysuptime) macro.
+This one is undefined by default in mib2.c. SNMP_GET_SYSUPTIME is called inside
+snmp_get_sysuptime(u32_t *value), and enable to change "sysuptime" value only
+when it's queried (any function which need "sysuptime" have to call
+snmp_get_sysuptime).
+
+
+3 Private MIBs
+==============
+
+If want to extend the agent with your own private MIB you'll need to
+add the following define to your local lwipopts.h:
+
+#define SNMP_PRIVATE_MIB        1
+
+You must provide the private_mib.h and associated files yourself.
+Note we don't have a "MIB compiler" that generates C source from a MIB,
+so you're required to do some serious coding if you enable this!
+
+Note the lwIP enterprise ID (26381) is assigned to the lwIP project,
+ALL OBJECT IDENTIFIERS LIVING UNDER THIS ID ARE ASSIGNED BY THE lwIP
+MAINTAINERS!
+
+If you need to create your own private MIB you'll need
+to apply for your own enterprise ID with IANA: http://www.iana.org/numbers.html 
+
+You can set it by passing a struct snmp_obj_id to the agent
+using snmp_set_sysobjid(&my_object_id), just before snmp_init().
+
+Note the object identifiers for thes MIB-2 and your private MIB
+tree must be kept in sorted ascending (lexicographical) order.
+This to ensure correct getnext operation.
+
+An example for a private MIB is part of the "minimal Unix" project:
+contrib/ports/unix/proj/minimal/lwip_prvmib.c
+
+The next chapter gives a more detailed description of the
+MIB-2 tree and the optional private MIB.
+
+4 The Gory Details
+==================
+
+4.0 Object identifiers and the MIB tree.
+
+We have three distinct parts for all object identifiers:
+
+The prefix
+  .iso.org.dod.internet
+
+the middle part 
+  .mgmt.mib-2.ip.ipNetToMediaTable.ipNetToMediaEntry.ipNetToMediaPhysAddress
+
+and the index part
+  .1.192.168.0.1
+
+Objects located above the .internet hierarchy aren't supported.
+Currently only the .mgmt sub-tree is available and
+when the SNMP_PRIVATE_MIB is enabled the .private tree
+becomes available too.
+
+Object identifiers from incoming requests are checked
+for a matching prefix, middle part and index part
+or are expanded(*) for GetNext requests with short
+or inexisting names in the request.
+(* we call this "expansion" but this also
+resembles the "auto-completion" operation)
+
+The middle part is usually located in ROM (const)
+to preserve precious RAM on small microcontrollers.
+However RAM location is possible for a dynamically
+changing private tree.
+
+The index part is handled by functions which in
+turn use dynamically allocated index trees from RAM.
+These trees are updated by e.g. the etharp code
+when new entries are made or removed form the ARP cache.
+
+/** @todo more gory details */

src/lwip-1.4.1/doc/sys_arch.txt

@@ -0,0 +1,267 @@
+sys_arch interface for lwIP 0.6++
+
+Author: Adam Dunkels
+
+The operating system emulation layer provides a common interface
+between the lwIP code and the underlying operating system kernel. The
+general idea is that porting lwIP to new architectures requires only
+small changes to a few header files and a new sys_arch
+implementation. It is also possible to do a sys_arch implementation
+that does not rely on any underlying operating system.
+
+The sys_arch provides semaphores and mailboxes to lwIP. For the full
+lwIP functionality, multiple threads support can be implemented in the
+sys_arch, but this is not required for the basic lwIP
+functionality. Previous versions of lwIP required the sys_arch to
+implement timer scheduling as well but as of lwIP 0.5 this is
+implemented in a higher layer.
+
+In addition to the source file providing the functionality of sys_arch,
+the OS emulation layer must provide several header files defining
+macros used throughout lwip.  The files required and the macros they
+must define are listed below the sys_arch description.
+
+Semaphores can be either counting or binary - lwIP works with both
+kinds. Mailboxes are used for message passing and can be implemented
+either as a queue which allows multiple messages to be posted to a
+mailbox, or as a rendez-vous point where only one message can be
+posted at a time. lwIP works with both kinds, but the former type will
+be more efficient. A message in a mailbox is just a pointer, nothing
+more. 
+
+Semaphores are represented by the type "sys_sem_t" which is typedef'd
+in the sys_arch.h file. Mailboxes are equivalently represented by the
+type "sys_mbox_t". lwIP does not place any restrictions on how
+sys_sem_t or sys_mbox_t are represented internally.
+
+Since lwIP 1.4.0, semaphore and mailbox functions are prototyped in a way that
+allows both using pointers or actual OS structures to be used. This way, memory
+required for such types can be either allocated in place (globally or on the
+stack) or on the heap (allocated internally in the "*_new()" functions).
+
+The following functions must be implemented by the sys_arch:
+
+- void sys_init(void)
+
+  Is called to initialize the sys_arch layer.
+
+- err_t sys_sem_new(sys_sem_t *sem, u8_t count)
+
+  Creates a new semaphore. The semaphore is allocated to the memory that 'sem'
+  points to (which can be both a pointer or the actual OS structure).
+  The "count" argument specifies the initial state of the semaphore (which is
+  either 0 or 1).
+  If the semaphore has been created, ERR_OK should be returned. Returning any
+  other error will provide a hint what went wrong, but except for assertions,
+  no real error handling is implemented.
+
+- void sys_sem_free(sys_sem_t *sem)
+
+  Deallocates a semaphore.
+
+- void sys_sem_signal(sys_sem_t *sem)
+
+  Signals a semaphore.
+
+- u32_t sys_arch_sem_wait(sys_sem_t *sem, u32_t timeout)
+
+  Blocks the thread while waiting for the semaphore to be
+  signaled. If the "timeout" argument is non-zero, the thread should
+  only be blocked for the specified time (measured in
+  milliseconds). If the "timeout" argument is zero, the thread should be
+  blocked until the semaphore is signalled.
+
+  If the timeout argument is non-zero, the return value is the number of
+  milliseconds spent waiting for the semaphore to be signaled. If the
+  semaphore wasn't signaled within the specified time, the return value is
+  SYS_ARCH_TIMEOUT. If the thread didn't have to wait for the semaphore
+  (i.e., it was already signaled), the function may return zero.
+
+  Notice that lwIP implements a function with a similar name,
+  sys_sem_wait(), that uses the sys_arch_sem_wait() function.
+
+- int sys_sem_valid(sys_sem_t *sem)
+
+  Returns 1 if the semaphore is valid, 0 if it is not valid.
+  When using pointers, a simple way is to check the pointer for != NULL.
+  When directly using OS structures, implementing this may be more complex.
+  This may also be a define, in which case the function is not prototyped.
+
+- void sys_sem_set_invalid(sys_sem_t *sem)
+
+  Invalidate a semaphore so that sys_sem_valid() returns 0.
+  ATTENTION: This does NOT mean that the semaphore shall be deallocated:
+  sys_sem_free() is always called before calling this function!
+  This may also be a define, in which case the function is not prototyped.
+
+- err_t sys_mbox_new(sys_mbox_t *mbox, int size)
+
+  Creates an empty mailbox for maximum "size" elements. Elements stored
+  in mailboxes are pointers. You have to define macros "_MBOX_SIZE"
+  in your lwipopts.h, or ignore this parameter in your implementation
+  and use a default size.
+  If the mailbox has been created, ERR_OK should be returned. Returning any
+  other error will provide a hint what went wrong, but except for assertions,
+  no real error handling is implemented.
+
+- void sys_mbox_free(sys_mbox_t *mbox)
+
+  Deallocates a mailbox. If there are messages still present in the
+  mailbox when the mailbox is deallocated, it is an indication of a
+  programming error in lwIP and the developer should be notified.
+
+- void sys_mbox_post(sys_mbox_t *mbox, void *msg)
+
+  Posts the "msg" to the mailbox. This function have to block until
+  the "msg" is really posted.
+
+- err_t sys_mbox_trypost(sys_mbox_t *mbox, void *msg)
+
+  Try to post the "msg" to the mailbox. Returns ERR_MEM if this one
+  is full, else, ERR_OK if the "msg" is posted.
+
+- u32_t sys_arch_mbox_fetch(sys_mbox_t *mbox, void **msg, u32_t timeout)
+
+  Blocks the thread until a message arrives in the mailbox, but does
+  not block the thread longer than "timeout" milliseconds (similar to
+  the sys_arch_sem_wait() function). If "timeout" is 0, the thread should
+  be blocked until a message arrives. The "msg" argument is a result
+  parameter that is set by the function (i.e., by doing "*msg =
+  ptr"). The "msg" parameter maybe NULL to indicate that the message
+  should be dropped.
+
+  The return values are the same as for the sys_arch_sem_wait() function:
+  Number of milliseconds spent waiting or SYS_ARCH_TIMEOUT if there was a
+  timeout.
+
+  Note that a function with a similar name, sys_mbox_fetch(), is
+  implemented by lwIP. 
+
+- u32_t sys_arch_mbox_tryfetch(sys_mbox_t *mbox, void **msg)
+
+  This is similar to sys_arch_mbox_fetch, however if a message is not
+  present in the mailbox, it immediately returns with the code
+  SYS_MBOX_EMPTY. On success 0 is returned.
+
+  To allow for efficient implementations, this can be defined as a
+  function-like macro in sys_arch.h instead of a normal function. For
+  example, a naive implementation could be:
+    #define sys_arch_mbox_tryfetch(mbox,msg) \
+      sys_arch_mbox_fetch(mbox,msg,1)
+  although this would introduce unnecessary delays.
+
+- int sys_mbox_valid(sys_mbox_t *mbox)
+
+  Returns 1 if the mailbox is valid, 0 if it is not valid.
+  When using pointers, a simple way is to check the pointer for != NULL.
+  When directly using OS structures, implementing this may be more complex.
+  This may also be a define, in which case the function is not prototyped.
+
+- void sys_mbox_set_invalid(sys_mbox_t *mbox)
+
+  Invalidate a mailbox so that sys_mbox_valid() returns 0.
+  ATTENTION: This does NOT mean that the mailbox shall be deallocated:
+  sys_mbox_free() is always called before calling this function!
+  This may also be a define, in which case the function is not prototyped.
+
+If threads are supported by the underlying operating system and if
+such functionality is needed in lwIP, the following function will have
+to be implemented as well:
+
+- sys_thread_t sys_thread_new(char *name, void (* thread)(void *arg), void *arg, int stacksize, int prio)
+
+  Starts a new thread named "name" with priority "prio" that will begin its
+  execution in the function "thread()". The "arg" argument will be passed as an
+  argument to the thread() function. The stack size to used for this thread is
+  the "stacksize" parameter. The id of the new thread is returned. Both the id
+  and the priority are system dependent.
+
+- sys_prot_t sys_arch_protect(void)
+
+  This optional function does a "fast" critical region protection and returns
+  the previous protection level. This function is only called during very short
+  critical regions. An embedded system which supports ISR-based drivers might
+  want to implement this function by disabling interrupts. Task-based systems
+  might want to implement this by using a mutex or disabling tasking. This
+  function should support recursive calls from the same task or interrupt. In
+  other words, sys_arch_protect() could be called while already protected. In
+  that case the return value indicates that it is already protected.
+
+  sys_arch_protect() is only required if your port is supporting an operating
+  system.
+
+- void sys_arch_unprotect(sys_prot_t pval)
+
+  This optional function does a "fast" set of critical region protection to the
+  value specified by pval. See the documentation for sys_arch_protect() for
+  more information. This function is only required if your port is supporting
+  an operating system.
+
+For some configurations, you also need:
+
+- u32_t sys_now(void)
+
+  This optional function returns the current time in milliseconds (don't care
+  for wraparound, this is only used for time diffs).
+  Not implementing this function means you cannot use some modules (e.g. TCP
+  timestamps, internal timeouts for NO_SYS==1).
+
+
+Note:
+
+Be carefull with using mem_malloc() in sys_arch. When malloc() refers to
+mem_malloc() you can run into a circular function call problem. In mem.c
+mem_init() tries to allcate a semaphore using mem_malloc, which of course
+can't be performed when sys_arch uses mem_malloc.
+
+-------------------------------------------------------------------------------
+Additional files required for the "OS support" emulation layer:
+-------------------------------------------------------------------------------
+
+cc.h       - Architecture environment, some compiler specific, some
+             environment specific (probably should move env stuff 
+             to sys_arch.h.)
+
+  Typedefs for the types used by lwip -
+    u8_t, s8_t, u16_t, s16_t, u32_t, s32_t, mem_ptr_t
+
+  Compiler hints for packing lwip's structures -
+    PACK_STRUCT_FIELD(x)
+    PACK_STRUCT_STRUCT
+    PACK_STRUCT_BEGIN
+    PACK_STRUCT_END
+
+  Platform specific diagnostic output -
+    LWIP_PLATFORM_DIAG(x)    - non-fatal, print a message.
+    LWIP_PLATFORM_ASSERT(x)  - fatal, print message and abandon execution.
+    Portability defines for printf formatters:
+    U16_F, S16_F, X16_F, U32_F, S32_F, X32_F, SZT_F
+
+  "lightweight" synchronization mechanisms -
+    SYS_ARCH_DECL_PROTECT(x) - declare a protection state variable.
+    SYS_ARCH_PROTECT(x)      - enter protection mode.
+    SYS_ARCH_UNPROTECT(x)    - leave protection mode.
+
+  If the compiler does not provide memset() this file must include a
+  definition of it, or include a file which defines it.
+
+  This file must either include a system-local <errno.h> which defines
+  the standard *nix error codes, or it should #define LWIP_PROVIDE_ERRNO
+  to make lwip/arch.h define the codes which are used throughout.
+
+
+perf.h     - Architecture specific performance measurement.
+  Measurement calls made throughout lwip, these can be defined to nothing.
+    PERF_START               - start measuring something.
+    PERF_STOP(x)             - stop measuring something, and record the result.
+
+sys_arch.h - Tied to sys_arch.c
+
+  Arch dependent types for the following objects:
+    sys_sem_t, sys_mbox_t, sys_thread_t,
+  And, optionally:
+    sys_prot_t
+
+  Defines to set vars of sys_mbox_t and sys_sem_t to NULL.
+    SYS_MBOX_NULL NULL
+    SYS_SEM_NULL NULL

src/lwip-1.4.1/src/FILES

@@ -0,0 +1,13 @@
+api/      - The code for the high-level wrapper API. Not needed if
+            you use the lowel-level call-back/raw API.
+
+core/     - The core of the TPC/IP stack; protocol implementations,
+            memory and buffer management, and the low-level raw API.
+
+include/  - lwIP include files.
+
+netif/    - Generic network interface device drivers are kept here,
+            as well as the ARP module.
+
+For more information on the various subdirectories, check the FILES
+file in each directory.

src/lwip-1.4.1/src/api/api_lib.c

@@ -0,0 +1,780 @@
+/**
+ * @file
+ * Sequential API External module
+ *
+ */
+ 
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+/* This is the part of the API that is linked with
+   the application */
+
+#include "lwip/opt.h"
+
+#if LWIP_NETCONN /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/api.h"
+#include "lwip/tcpip.h"
+#include "lwip/memp.h"
+
+#include "lwip/ip.h"
+#include "lwip/raw.h"
+#include "lwip/udp.h"
+#include "lwip/tcp.h"
+
+#include <string.h>
+
+/**
+ * Create a new netconn (of a specific type) that has a callback function.
+ * The corresponding pcb is also created.
+ *
+ * @param t the type of 'connection' to create (@see enum netconn_type)
+ * @param proto the IP protocol for RAW IP pcbs
+ * @param callback a function to call on status changes (RX available, TX'ed)
+ * @return a newly allocated struct netconn or
+ *         NULL on memory error
+ */
+struct netconn*
+netconn_new_with_proto_and_callback(enum netconn_type t, u8_t proto, netconn_callback callback)
+{
+  struct netconn *conn;
+  struct api_msg msg;
+
+  conn = netconn_alloc(t, callback);
+  if (conn != NULL) {
+    msg.function = do_newconn;
+    msg.msg.msg.n.proto = proto;
+    msg.msg.conn = conn;
+    if (TCPIP_APIMSG(&msg) != ERR_OK) {
+      LWIP_ASSERT("freeing conn without freeing pcb", conn->pcb.tcp == NULL);
+      LWIP_ASSERT("conn has no op_completed", sys_sem_valid(&conn->op_completed));
+      LWIP_ASSERT("conn has no recvmbox", sys_mbox_valid(&conn->recvmbox));
+#if LWIP_TCP
+      LWIP_ASSERT("conn->acceptmbox shouldn't exist", !sys_mbox_valid(&conn->acceptmbox));
+#endif /* LWIP_TCP */
+      sys_sem_free(&conn->op_completed);
+      sys_mbox_free(&conn->recvmbox);
+      memp_free(MEMP_NETCONN, conn);
+      return NULL;
+    }
+  }
+  return conn;
+}
+
+/**
+ * Close a netconn 'connection' and free its resources.
+ * UDP and RAW connection are completely closed, TCP pcbs might still be in a waitstate
+ * after this returns.
+ *
+ * @param conn the netconn to delete
+ * @return ERR_OK if the connection was deleted
+ */
+err_t
+netconn_delete(struct netconn *conn)
+{
+  struct api_msg msg;
+
+  /* No ASSERT here because possible to get a (conn == NULL) if we got an accept error */
+  if (conn == NULL) {
+    return ERR_OK;
+  }
+
+  msg.function = do_delconn;
+  msg.msg.conn = conn;
+  tcpip_apimsg(&msg);
+
+  netconn_free(conn);
+
+  /* don't care for return value of do_delconn since it only calls void functions */
+
+  return ERR_OK;
+}
+
+/**
+ * Get the local or remote IP address and port of a netconn.
+ * For RAW netconns, this returns the protocol instead of a port!
+ *
+ * @param conn the netconn to query
+ * @param addr a pointer to which to save the IP address
+ * @param port a pointer to which to save the port (or protocol for RAW)
+ * @param local 1 to get the local IP address, 0 to get the remote one
+ * @return ERR_CONN for invalid connections
+ *         ERR_OK if the information was retrieved
+ */
+err_t
+netconn_getaddr(struct netconn *conn, ip_addr_t *addr, u16_t *port, u8_t local)
+{
+  struct api_msg msg;
+  err_t err;
+
+  LWIP_ERROR("netconn_getaddr: invalid conn", (conn != NULL), return ERR_ARG;);
+  LWIP_ERROR("netconn_getaddr: invalid addr", (addr != NULL), return ERR_ARG;);
+  LWIP_ERROR("netconn_getaddr: invalid port", (port != NULL), return ERR_ARG;);
+
+  msg.function = do_getaddr;
+  msg.msg.conn = conn;
+  msg.msg.msg.ad.ipaddr = addr;
+  msg.msg.msg.ad.port = port;
+  msg.msg.msg.ad.local = local;
+  err = TCPIP_APIMSG(&msg);
+
+  NETCONN_SET_SAFE_ERR(conn, err);
+  return err;
+}
+
+/**
+ * Bind a netconn to a specific local IP address and port.
+ * Binding one netconn twice might not always be checked correctly!
+ *
+ * @param conn the netconn to bind
+ * @param addr the local IP address to bind the netconn to (use IP_ADDR_ANY
+ *             to bind to all addresses)
+ * @param port the local port to bind the netconn to (not used for RAW)
+ * @return ERR_OK if bound, any other err_t on failure
+ */
+err_t
+netconn_bind(struct netconn *conn, ip_addr_t *addr, u16_t port)
+{
+  struct api_msg msg;
+  err_t err;
+
+  LWIP_ERROR("netconn_bind: invalid conn", (conn != NULL), return ERR_ARG;);
+
+  msg.function = do_bind;
+  msg.msg.conn = conn;
+  msg.msg.msg.bc.ipaddr = addr;
+  msg.msg.msg.bc.port = port;
+  err = TCPIP_APIMSG(&msg);
+
+  NETCONN_SET_SAFE_ERR(conn, err);
+  return err;
+}
+
+/**
+ * Connect a netconn to a specific remote IP address and port.
+ *
+ * @param conn the netconn to connect
+ * @param addr the remote IP address to connect to
+ * @param port the remote port to connect to (no used for RAW)
+ * @return ERR_OK if connected, return value of tcp_/udp_/raw_connect otherwise
+ */
+err_t
+netconn_connect(struct netconn *conn, ip_addr_t *addr, u16_t port)
+{
+  struct api_msg msg;
+  err_t err;
+
+  LWIP_ERROR("netconn_connect: invalid conn", (conn != NULL), return ERR_ARG;);
+
+  msg.function = do_connect;
+  msg.msg.conn = conn;
+  msg.msg.msg.bc.ipaddr = addr;
+  msg.msg.msg.bc.port = port;
+  /* This is the only function which need to not block tcpip_thread */
+  err = tcpip_apimsg(&msg);
+
+  NETCONN_SET_SAFE_ERR(conn, err);
+  return err;
+}
+
+/**
+ * Disconnect a netconn from its current peer (only valid for UDP netconns).
+ *
+ * @param conn the netconn to disconnect
+ * @return TODO: return value is not set here...
+ */
+err_t
+netconn_disconnect(struct netconn *conn)
+{
+  struct api_msg msg;
+  err_t err;
+
+  LWIP_ERROR("netconn_disconnect: invalid conn", (conn != NULL), return ERR_ARG;);
+
+  msg.function = do_disconnect;
+  msg.msg.conn = conn;
+  err = TCPIP_APIMSG(&msg);
+
+  NETCONN_SET_SAFE_ERR(conn, err);
+  return err;
+}
+
+/**
+ * Set a TCP netconn into listen mode
+ *
+ * @param conn the tcp netconn to set to listen mode
+ * @param backlog the listen backlog, only used if TCP_LISTEN_BACKLOG==1
+ * @return ERR_OK if the netconn was set to listen (UDP and RAW netconns
+ *         don't return any error (yet?))
+ */
+err_t
+netconn_listen_with_backlog(struct netconn *conn, u8_t backlog)
+{
+#if LWIP_TCP
+  struct api_msg msg;
+  err_t err;
+
+  /* This does no harm. If TCP_LISTEN_BACKLOG is off, backlog is unused. */
+  LWIP_UNUSED_ARG(backlog);
+
+  LWIP_ERROR("netconn_listen: invalid conn", (conn != NULL), return ERR_ARG;);
+
+  msg.function = do_listen;
+  msg.msg.conn = conn;
+#if TCP_LISTEN_BACKLOG
+  msg.msg.msg.lb.backlog = backlog;
+#endif /* TCP_LISTEN_BACKLOG */
+  err = TCPIP_APIMSG(&msg);
+
+  NETCONN_SET_SAFE_ERR(conn, err);
+  return err;
+#else /* LWIP_TCP */
+  LWIP_UNUSED_ARG(conn);
+  LWIP_UNUSED_ARG(backlog);
+  return ERR_ARG;
+#endif /* LWIP_TCP */
+}
+
+/**
+ * Accept a new connection on a TCP listening netconn.
+ *
+ * @param conn the TCP listen netconn
+ * @param new_conn pointer where the new connection is stored
+ * @return ERR_OK if a new connection has been received or an error
+ *                code otherwise
+ */
+err_t
+netconn_accept(struct netconn *conn, struct netconn **new_conn)
+{
+#if LWIP_TCP
+  struct netconn *newconn;
+  err_t err;
+#if TCP_LISTEN_BACKLOG
+  struct api_msg msg;
+#endif /* TCP_LISTEN_BACKLOG */
+
+  LWIP_ERROR("netconn_accept: invalid pointer",    (new_conn != NULL),                  return ERR_ARG;);
+  *new_conn = NULL;
+  LWIP_ERROR("netconn_accept: invalid conn",       (conn != NULL),                      return ERR_ARG;);
+  LWIP_ERROR("netconn_accept: invalid acceptmbox", sys_mbox_valid(&conn->acceptmbox),   return ERR_ARG;);
+
+  err = conn->last_err;
+  if (ERR_IS_FATAL(err)) {
+    /* don't recv on fatal errors: this might block the application task
+       waiting on acceptmbox forever! */
+    return err;
+  }
+
+#if LWIP_SO_RCVTIMEO
+  if (sys_arch_mbox_fetch(&conn->acceptmbox, (void **)&newconn, conn->recv_timeout) == SYS_ARCH_TIMEOUT) {
+    NETCONN_SET_SAFE_ERR(conn, ERR_TIMEOUT);
+    return ERR_TIMEOUT;
+  }
+#else
+  sys_arch_mbox_fetch(&conn->acceptmbox, (void **)&newconn, 0);
+#endif /* LWIP_SO_RCVTIMEO*/
+  /* Register event with callback */
+  API_EVENT(conn, NETCONN_EVT_RCVMINUS, 0);
+
+  if (newconn == NULL) {
+    /* connection has been aborted */
+    NETCONN_SET_SAFE_ERR(conn, ERR_ABRT);
+    return ERR_ABRT;
+  }
+#if TCP_LISTEN_BACKLOG
+  /* Let the stack know that we have accepted the connection. */
+  msg.function = do_recv;
+  msg.msg.conn = conn;
+  /* don't care for the return value of do_recv */
+  TCPIP_APIMSG(&msg);
+#endif /* TCP_LISTEN_BACKLOG */
+
+  *new_conn = newconn;
+  /* don't set conn->last_err: it's only ERR_OK, anyway */
+  return ERR_OK;
+#else /* LWIP_TCP */
+  LWIP_UNUSED_ARG(conn);
+  LWIP_UNUSED_ARG(new_conn);
+  return ERR_ARG;
+#endif /* LWIP_TCP */
+}
+
+/**
+ * Receive data: actual implementation that doesn't care whether pbuf or netbuf
+ * is received
+ *
+ * @param conn the netconn from which to receive data
+ * @param new_buf pointer where a new pbuf/netbuf is stored when received data
+ * @return ERR_OK if data has been received, an error code otherwise (timeout,
+ *                memory error or another error)
+ */
+static err_t
+netconn_recv_data(struct netconn *conn, void **new_buf)
+{
+  void *buf = NULL;
+  u16_t len;
+  err_t err;
+#if LWIP_TCP
+  struct api_msg msg;
+#endif /* LWIP_TCP */
+
+  LWIP_ERROR("netconn_recv: invalid pointer", (new_buf != NULL), return ERR_ARG;);
+  *new_buf = NULL;
+  LWIP_ERROR("netconn_recv: invalid conn",    (conn != NULL),    return ERR_ARG;);
+  LWIP_ERROR("netconn_accept: invalid recvmbox", sys_mbox_valid(&conn->recvmbox), return ERR_CONN;);
+
+  err = conn->last_err;
+  if (ERR_IS_FATAL(err)) {
+    /* don't recv on fatal errors: this might block the application task
+       waiting on recvmbox forever! */
+    /* @todo: this does not allow us to fetch data that has been put into recvmbox
+       before the fatal error occurred - is that a problem? */
+    return err;
+  }
+
+#if LWIP_SO_RCVTIMEO
+  if (sys_arch_mbox_fetch(&conn->recvmbox, &buf, conn->recv_timeout) == SYS_ARCH_TIMEOUT) {
+    NETCONN_SET_SAFE_ERR(conn, ERR_TIMEOUT);
+    return ERR_TIMEOUT;
+  }
+#else
+  sys_arch_mbox_fetch(&conn->recvmbox, &buf, 0);
+#endif /* LWIP_SO_RCVTIMEO*/
+
+#if LWIP_TCP
+#if (LWIP_UDP || LWIP_RAW)
+  if (conn->type == NETCONN_TCP)
+#endif /* (LWIP_UDP || LWIP_RAW) */
+  {
+    if (!netconn_get_noautorecved(conn) || (buf == NULL)) {
+      /* Let the stack know that we have taken the data. */
+      /* TODO: Speedup: Don't block and wait for the answer here
+         (to prevent multiple thread-switches). */
+      msg.function = do_recv;
+      msg.msg.conn = conn;
+      if (buf != NULL) {
+        msg.msg.msg.r.len = ((struct pbuf *)buf)->tot_len;
+      } else {
+        msg.msg.msg.r.len = 1;
+      }
+      /* don't care for the return value of do_recv */
+      TCPIP_APIMSG(&msg);
+    }
+
+    /* If we are closed, we indicate that we no longer wish to use the socket */
+    if (buf == NULL) {
+      API_EVENT(conn, NETCONN_EVT_RCVMINUS, 0);
+      /* Avoid to lose any previous error code */
+      NETCONN_SET_SAFE_ERR(conn, ERR_CLSD);
+      return ERR_CLSD;
+    }
+    len = ((struct pbuf *)buf)->tot_len;
+  }
+#endif /* LWIP_TCP */
+#if LWIP_TCP && (LWIP_UDP || LWIP_RAW)
+  else
+#endif /* LWIP_TCP && (LWIP_UDP || LWIP_RAW) */
+#if (LWIP_UDP || LWIP_RAW)
+  {
+    LWIP_ASSERT("buf != NULL", buf != NULL);
+    len = netbuf_len((struct netbuf *)buf);
+  }
+#endif /* (LWIP_UDP || LWIP_RAW) */
+
+#if LWIP_SO_RCVBUF
+  SYS_ARCH_DEC(conn->recv_avail, len);
+#endif /* LWIP_SO_RCVBUF */
+  /* Register event with callback */
+  API_EVENT(conn, NETCONN_EVT_RCVMINUS, len);
+
+  LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_recv_data: received %p, len=%"U16_F"\n", buf, len));
+
+  *new_buf = buf;
+  /* don't set conn->last_err: it's only ERR_OK, anyway */
+  return ERR_OK;
+}
+
+/**
+ * Receive data (in form of a pbuf) from a TCP netconn
+ *
+ * @param conn the netconn from which to receive data
+ * @param new_buf pointer where a new pbuf is stored when received data
+ * @return ERR_OK if data has been received, an error code otherwise (timeout,
+ *                memory error or another error)
+ *         ERR_ARG if conn is not a TCP netconn
+ */
+err_t
+netconn_recv_tcp_pbuf(struct netconn *conn, struct pbuf **new_buf)
+{
+  LWIP_ERROR("netconn_recv: invalid conn", (conn != NULL) &&
+             netconn_type(conn) == NETCONN_TCP, return ERR_ARG;);
+
+  return netconn_recv_data(conn, (void **)new_buf);
+}
+
+/**
+ * Receive data (in form of a netbuf containing a packet buffer) from a netconn
+ *
+ * @param conn the netconn from which to receive data
+ * @param new_buf pointer where a new netbuf is stored when received data
+ * @return ERR_OK if data has been received, an error code otherwise (timeout,
+ *                memory error or another error)
+ */
+err_t
+netconn_recv(struct netconn *conn, struct netbuf **new_buf)
+{
+#if LWIP_TCP
+  struct netbuf *buf = NULL;
+  err_t err;
+#endif /* LWIP_TCP */
+
+  LWIP_ERROR("netconn_recv: invalid pointer", (new_buf != NULL), return ERR_ARG;);
+  *new_buf = NULL;
+  LWIP_ERROR("netconn_recv: invalid conn",    (conn != NULL),    return ERR_ARG;);
+  LWIP_ERROR("netconn_accept: invalid recvmbox", sys_mbox_valid(&conn->recvmbox), return ERR_CONN;);
+
+#if LWIP_TCP
+#if (LWIP_UDP || LWIP_RAW)
+  if (conn->type == NETCONN_TCP)
+#endif /* (LWIP_UDP || LWIP_RAW) */
+  {
+    struct pbuf *p = NULL;
+    /* This is not a listening netconn, since recvmbox is set */
+
+    buf = (struct netbuf *)memp_malloc(MEMP_NETBUF);
+    if (buf == NULL) {
+      NETCONN_SET_SAFE_ERR(conn, ERR_MEM);
+      return ERR_MEM;
+    }
+
+    err = netconn_recv_data(conn, (void **)&p);
+    if (err != ERR_OK) {
+      memp_free(MEMP_NETBUF, buf);
+      return err;
+    }
+    LWIP_ASSERT("p != NULL", p != NULL);
+
+    buf->p = p;
+    buf->ptr = p;
+    buf->port = 0;
+    ip_addr_set_any(&buf->addr);
+    *new_buf = buf;
+    /* don't set conn->last_err: it's only ERR_OK, anyway */
+    return ERR_OK;
+  }
+#endif /* LWIP_TCP */
+#if LWIP_TCP && (LWIP_UDP || LWIP_RAW)
+  else
+#endif /* LWIP_TCP && (LWIP_UDP || LWIP_RAW) */
+  {
+#if (LWIP_UDP || LWIP_RAW)
+    return netconn_recv_data(conn, (void **)new_buf);
+#endif /* (LWIP_UDP || LWIP_RAW) */
+  }
+}
+
+/**
+ * TCP: update the receive window: by calling this, the application
+ * tells the stack that it has processed data and is able to accept
+ * new data.
+ * ATTENTION: use with care, this is mainly used for sockets!
+ * Can only be used when calling netconn_set_noautorecved(conn, 1) before.
+ *
+ * @param conn the netconn for which to update the receive window
+ * @param length amount of data processed (ATTENTION: this must be accurate!)
+ */
+void
+netconn_recved(struct netconn *conn, u32_t length)
+{
+#if LWIP_TCP
+  if ((conn != NULL) && (conn->type == NETCONN_TCP) &&
+      (netconn_get_noautorecved(conn))) {
+    struct api_msg msg;
+    /* Let the stack know that we have taken the data. */
+    /* TODO: Speedup: Don't block and wait for the answer here
+       (to prevent multiple thread-switches). */
+    msg.function = do_recv;
+    msg.msg.conn = conn;
+    msg.msg.msg.r.len = length;
+    /* don't care for the return value of do_recv */
+    TCPIP_APIMSG(&msg);
+  }
+#else /* LWIP_TCP */
+  LWIP_UNUSED_ARG(conn);
+  LWIP_UNUSED_ARG(length);
+#endif /* LWIP_TCP */
+}
+
+/**
+ * Send data (in form of a netbuf) to a specific remote IP address and port.
+ * Only to be used for UDP and RAW netconns (not TCP).
+ *
+ * @param conn the netconn over which to send data
+ * @param buf a netbuf containing the data to send
+ * @param addr the remote IP address to which to send the data
+ * @param port the remote port to which to send the data
+ * @return ERR_OK if data was sent, any other err_t on error
+ */
+err_t
+netconn_sendto(struct netconn *conn, struct netbuf *buf, ip_addr_t *addr, u16_t port)
+{
+  if (buf != NULL) {
+    ip_addr_set(&buf->addr, addr);
+    buf->port = port;
+    return netconn_send(conn, buf);
+  }
+  return ERR_VAL;
+}
+
+/**
+ * Send data over a UDP or RAW netconn (that is already connected).
+ *
+ * @param conn the UDP or RAW netconn over which to send data
+ * @param buf a netbuf containing the data to send
+ * @return ERR_OK if data was sent, any other err_t on error
+ */
+err_t
+netconn_send(struct netconn *conn, struct netbuf *buf)
+{
+  struct api_msg msg;
+  err_t err;
+
+  LWIP_ERROR("netconn_send: invalid conn",  (conn != NULL), return ERR_ARG;);
+
+  LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_send: sending %"U16_F" bytes\n", buf->p->tot_len));
+  msg.function = do_send;
+  msg.msg.conn = conn;
+  msg.msg.msg.b = buf;
+  err = TCPIP_APIMSG(&msg);
+
+  NETCONN_SET_SAFE_ERR(conn, err);
+  return err;
+}
+
+/**
+ * Send data over a TCP netconn.
+ *
+ * @param conn the TCP netconn over which to send data
+ * @param dataptr pointer to the application buffer that contains the data to send
+ * @param size size of the application data to send
+ * @param apiflags combination of following flags :
+ * - NETCONN_COPY: data will be copied into memory belonging to the stack
+ * - NETCONN_MORE: for TCP connection, PSH flag will be set on last segment sent
+ * - NETCONN_DONTBLOCK: only write the data if all dat can be written at once
+ * @param bytes_written pointer to a location that receives the number of written bytes
+ * @return ERR_OK if data was sent, any other err_t on error
+ */
+err_t
+netconn_write_partly(struct netconn *conn, const void *dataptr, size_t size,
+                     u8_t apiflags, size_t *bytes_written)
+{
+  struct api_msg msg;
+  err_t err;
+  u8_t dontblock;
+
+  LWIP_ERROR("netconn_write: invalid conn",  (conn != NULL), return ERR_ARG;);
+  LWIP_ERROR("netconn_write: invalid conn->type",  (conn->type == NETCONN_TCP), return ERR_VAL;);
+  if (size == 0) {
+    return ERR_OK;
+  }
+  dontblock = netconn_is_nonblocking(conn) || (apiflags & NETCONN_DONTBLOCK);
+  if (dontblock && !bytes_written) {
+    /* This implies netconn_write() cannot be used for non-blocking send, since
+       it has no way to return the number of bytes written. */
+    return ERR_VAL;
+  }
+
+  /* non-blocking write sends as much  */
+  msg.function = do_write;
+  msg.msg.conn = conn;
+  msg.msg.msg.w.dataptr = dataptr;
+  msg.msg.msg.w.apiflags = apiflags;
+  msg.msg.msg.w.len = size;
+#if LWIP_SO_SNDTIMEO
+  if (conn->send_timeout != 0) {
+    /* get the time we started, which is later compared to
+        sys_now() + conn->send_timeout */
+    msg.msg.msg.w.time_started = sys_now();
+  } else {
+    msg.msg.msg.w.time_started = 0;
+  }
+#endif /* LWIP_SO_SNDTIMEO */
+
+  /* For locking the core: this _can_ be delayed on low memory/low send buffer,
+     but if it is, this is done inside api_msg.c:do_write(), so we can use the
+     non-blocking version here. */
+  err = TCPIP_APIMSG(&msg);
+  if ((err == ERR_OK) && (bytes_written != NULL)) {
+    if (dontblock
+#if LWIP_SO_SNDTIMEO
+        || (conn->send_timeout != 0)
+#endif /* LWIP_SO_SNDTIMEO */
+       ) {
+      /* nonblocking write: maybe the data has been sent partly */
+      *bytes_written = msg.msg.msg.w.len;
+    } else {
+      /* blocking call succeeded: all data has been sent if it */
+      *bytes_written = size;
+    }
+  }
+
+  NETCONN_SET_SAFE_ERR(conn, err);
+  return err;
+}
+
+/**
+ * Close ot shutdown a TCP netconn (doesn't delete it).
+ *
+ * @param conn the TCP netconn to close or shutdown
+ * @param how fully close or only shutdown one side?
+ * @return ERR_OK if the netconn was closed, any other err_t on error
+ */
+static err_t
+netconn_close_shutdown(struct netconn *conn, u8_t how)
+{
+  struct api_msg msg;
+  err_t err;
+
+  LWIP_ERROR("netconn_close: invalid conn",  (conn != NULL), return ERR_ARG;);
+
+  msg.function = do_close;
+  msg.msg.conn = conn;
+  /* shutting down both ends is the same as closing */
+  msg.msg.msg.sd.shut = how;
+  /* because of the LWIP_TCPIP_CORE_LOCKING implementation of do_close,
+     don't use TCPIP_APIMSG here */
+  err = tcpip_apimsg(&msg);
+
+  NETCONN_SET_SAFE_ERR(conn, err);
+  return err;
+}
+
+/**
+ * Close a TCP netconn (doesn't delete it).
+ *
+ * @param conn the TCP netconn to close
+ * @return ERR_OK if the netconn was closed, any other err_t on error
+ */
+err_t
+netconn_close(struct netconn *conn)
+{
+  /* shutting down both ends is the same as closing */
+  return netconn_close_shutdown(conn, NETCONN_SHUT_RDWR);
+}
+
+/**
+ * Shut down one or both sides of a TCP netconn (doesn't delete it).
+ *
+ * @param conn the TCP netconn to shut down
+ * @return ERR_OK if the netconn was closed, any other err_t on error
+ */
+err_t
+netconn_shutdown(struct netconn *conn, u8_t shut_rx, u8_t shut_tx)
+{
+  return netconn_close_shutdown(conn, (shut_rx ? NETCONN_SHUT_RD : 0) | (shut_tx ? NETCONN_SHUT_WR : 0));
+}
+
+#if LWIP_IGMP
+/**
+ * Join multicast groups for UDP netconns.
+ *
+ * @param conn the UDP netconn for which to change multicast addresses
+ * @param multiaddr IP address of the multicast group to join or leave
+ * @param netif_addr the IP address of the network interface on which to send
+ *                  the igmp message
+ * @param join_or_leave flag whether to send a join- or leave-message
+ * @return ERR_OK if the action was taken, any err_t on error
+ */
+err_t
+netconn_join_leave_group(struct netconn *conn,
+                         ip_addr_t *multiaddr,
+                         ip_addr_t *netif_addr,
+                         enum netconn_igmp join_or_leave)
+{
+  struct api_msg msg;
+  err_t err;
+
+  LWIP_ERROR("netconn_join_leave_group: invalid conn",  (conn != NULL), return ERR_ARG;);
+
+  msg.function = do_join_leave_group;
+  msg.msg.conn = conn;
+  msg.msg.msg.jl.multiaddr = multiaddr;
+  msg.msg.msg.jl.netif_addr = netif_addr;
+  msg.msg.msg.jl.join_or_leave = join_or_leave;
+  err = TCPIP_APIMSG(&msg);
+
+  NETCONN_SET_SAFE_ERR(conn, err);
+  return err;
+}
+#endif /* LWIP_IGMP */
+
+#if LWIP_DNS
+/**
+ * Execute a DNS query, only one IP address is returned
+ *
+ * @param name a string representation of the DNS host name to query
+ * @param addr a preallocated ip_addr_t where to store the resolved IP address
+ * @return ERR_OK: resolving succeeded
+ *         ERR_MEM: memory error, try again later
+ *         ERR_ARG: dns client not initialized or invalid hostname
+ *         ERR_VAL: dns server response was invalid
+ */
+err_t
+netconn_gethostbyname(const char *name, ip_addr_t *addr)
+{
+  struct dns_api_msg msg;
+  err_t err;
+  sys_sem_t sem;
+
+  LWIP_ERROR("netconn_gethostbyname: invalid name", (name != NULL), return ERR_ARG;);
+  LWIP_ERROR("netconn_gethostbyname: invalid addr", (addr != NULL), return ERR_ARG;);
+
+  err = sys_sem_new(&sem, 0);
+  if (err != ERR_OK) {
+    return err;
+  }
+
+  msg.name = name;
+  msg.addr = addr;
+  msg.err = &err;
+  msg.sem = &sem;
+
+  tcpip_callback(do_gethostbyname, &msg);
+  sys_sem_wait(&sem);
+  sys_sem_free(&sem);
+
+  return err;
+}
+#endif /* LWIP_DNS*/
+
+#endif /* LWIP_NETCONN */

src/lwip-1.4.1/src/api/err.c

@@ -0,0 +1,75 @@
+/**
+ * @file
+ * Error Management module
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/err.h"
+
+#ifdef LWIP_DEBUG
+
+static const char *err_strerr[] = {
+           "Ok.",                    /* ERR_OK          0  */
+           "Out of memory error.",   /* ERR_MEM        -1  */
+           "Buffer error.",          /* ERR_BUF        -2  */
+           "Timeout.",               /* ERR_TIMEOUT    -3  */
+           "Routing problem.",       /* ERR_RTE        -4  */
+           "Operation in progress.", /* ERR_INPROGRESS -5  */
+           "Illegal value.",         /* ERR_VAL        -6  */
+           "Operation would block.", /* ERR_WOULDBLOCK -7  */
+           "Address in use.",        /* ERR_USE        -8  */
+           "Already connected.",     /* ERR_ISCONN     -9  */
+           "Connection aborted.",    /* ERR_ABRT       -10 */
+           "Connection reset.",      /* ERR_RST        -11 */
+           "Connection closed.",     /* ERR_CLSD       -12 */
+           "Not connected.",         /* ERR_CONN       -13 */
+           "Illegal argument.",      /* ERR_ARG        -14 */
+           "Low-level netif error.", /* ERR_IF         -15 */
+};
+
+/**
+ * Convert an lwip internal error to a string representation.
+ *
+ * @param err an lwip internal err_t
+ * @return a string representation for err
+ */
+const char *
+lwip_strerr(err_t err)
+{
+  return err_strerr[-err];
+
+}
+
+#endif /* LWIP_DEBUG */

src/lwip-1.4.1/src/api/netbuf.c

@@ -0,0 +1,245 @@
+/**
+ * @file
+ * Network buffer management
+ *
+ */
+ 
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_NETCONN /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/netbuf.h"
+#include "lwip/memp.h"
+
+#include <string.h>
+
+/**
+ * Create (allocate) and initialize a new netbuf.
+ * The netbuf doesn't yet contain a packet buffer!
+ *
+ * @return a pointer to a new netbuf
+ *         NULL on lack of memory
+ */
+struct
+netbuf *netbuf_new(void)
+{
+  struct netbuf *buf;
+
+  buf = (struct netbuf *)memp_malloc(MEMP_NETBUF);
+  if (buf != NULL) {
+    buf->p = NULL;
+    buf->ptr = NULL;
+    ip_addr_set_any(&buf->addr);
+    buf->port = 0;
+#if LWIP_NETBUF_RECVINFO || LWIP_CHECKSUM_ON_COPY
+#if LWIP_CHECKSUM_ON_COPY
+    buf->flags = 0;
+#endif /* LWIP_CHECKSUM_ON_COPY */
+    buf->toport_chksum = 0;
+#if LWIP_NETBUF_RECVINFO
+    ip_addr_set_any(&buf->toaddr);
+#endif /* LWIP_NETBUF_RECVINFO */
+#endif /* LWIP_NETBUF_RECVINFO || LWIP_CHECKSUM_ON_COPY */
+    return buf;
+  } else {
+    return NULL;
+  }
+}
+
+/**
+ * Deallocate a netbuf allocated by netbuf_new().
+ *
+ * @param buf pointer to a netbuf allocated by netbuf_new()
+ */
+void
+netbuf_delete(struct netbuf *buf)
+{
+  if (buf != NULL) {
+    if (buf->p != NULL) {
+      pbuf_free(buf->p);
+      buf->p = buf->ptr = NULL;
+    }
+    memp_free(MEMP_NETBUF, buf);
+  }
+}
+
+/**
+ * Allocate memory for a packet buffer for a given netbuf.
+ *
+ * @param buf the netbuf for which to allocate a packet buffer
+ * @param size the size of the packet buffer to allocate
+ * @return pointer to the allocated memory
+ *         NULL if no memory could be allocated
+ */
+void *
+netbuf_alloc(struct netbuf *buf, u16_t size)
+{
+  LWIP_ERROR("netbuf_alloc: invalid buf", (buf != NULL), return NULL;);
+
+  /* Deallocate any previously allocated memory. */
+  if (buf->p != NULL) {
+    pbuf_free(buf->p);
+  }
+  buf->p = pbuf_alloc(PBUF_TRANSPORT, size, PBUF_RAM);
+  if (buf->p == NULL) {
+     return NULL;
+  }
+  LWIP_ASSERT("check that first pbuf can hold size",
+             (buf->p->len >= size));
+  buf->ptr = buf->p;
+  return buf->p->payload;
+}
+
+/**
+ * Free the packet buffer included in a netbuf
+ *
+ * @param buf pointer to the netbuf which contains the packet buffer to free
+ */
+void
+netbuf_free(struct netbuf *buf)
+{
+  LWIP_ERROR("netbuf_free: invalid buf", (buf != NULL), return;);
+  if (buf->p != NULL) {
+    pbuf_free(buf->p);
+  }
+  buf->p = buf->ptr = NULL;
+}
+
+/**
+ * Let a netbuf reference existing (non-volatile) data.
+ *
+ * @param buf netbuf which should reference the data
+ * @param dataptr pointer to the data to reference
+ * @param size size of the data
+ * @return ERR_OK if data is referenced
+ *         ERR_MEM if data couldn't be referenced due to lack of memory
+ */
+err_t
+netbuf_ref(struct netbuf *buf, const void *dataptr, u16_t size)
+{
+  LWIP_ERROR("netbuf_ref: invalid buf", (buf != NULL), return ERR_ARG;);
+  if (buf->p != NULL) {
+    pbuf_free(buf->p);
+  }
+  buf->p = pbuf_alloc(PBUF_TRANSPORT, 0, PBUF_REF);
+  if (buf->p == NULL) {
+    buf->ptr = NULL;
+    return ERR_MEM;
+  }
+  buf->p->payload = (void*)dataptr;
+  buf->p->len = buf->p->tot_len = size;
+  buf->ptr = buf->p;
+  return ERR_OK;
+}
+
+/**
+ * Chain one netbuf to another (@see pbuf_chain)
+ *
+ * @param head the first netbuf
+ * @param tail netbuf to chain after head, freed by this function, may not be reference after returning
+ */
+void
+netbuf_chain(struct netbuf *head, struct netbuf *tail)
+{
+  LWIP_ERROR("netbuf_ref: invalid head", (head != NULL), return;);
+  LWIP_ERROR("netbuf_chain: invalid tail", (tail != NULL), return;);
+  pbuf_cat(head->p, tail->p);
+  head->ptr = head->p;
+  memp_free(MEMP_NETBUF, tail);
+}
+
+/**
+ * Get the data pointer and length of the data inside a netbuf.
+ *
+ * @param buf netbuf to get the data from
+ * @param dataptr pointer to a void pointer where to store the data pointer
+ * @param len pointer to an u16_t where the length of the data is stored
+ * @return ERR_OK if the information was retreived,
+ *         ERR_BUF on error.
+ */
+err_t
+netbuf_data(struct netbuf *buf, void **dataptr, u16_t *len)
+{
+  LWIP_ERROR("netbuf_data: invalid buf", (buf != NULL), return ERR_ARG;);
+  LWIP_ERROR("netbuf_data: invalid dataptr", (dataptr != NULL), return ERR_ARG;);
+  LWIP_ERROR("netbuf_data: invalid len", (len != NULL), return ERR_ARG;);
+
+  if (buf->ptr == NULL) {
+    return ERR_BUF;
+  }
+  *dataptr = buf->ptr->payload;
+  *len = buf->ptr->len;
+  return ERR_OK;
+}
+
+/**
+ * Move the current data pointer of a packet buffer contained in a netbuf
+ * to the next part.
+ * The packet buffer itself is not modified.
+ *
+ * @param buf the netbuf to modify
+ * @return -1 if there is no next part
+ *         1  if moved to the next part but now there is no next part
+ *         0  if moved to the next part and there are still more parts
+ */
+s8_t
+netbuf_next(struct netbuf *buf)
+{
+  LWIP_ERROR("netbuf_free: invalid buf", (buf != NULL), return -1;);
+  if (buf->ptr->next == NULL) {
+    return -1;
+  }
+  buf->ptr = buf->ptr->next;
+  if (buf->ptr->next == NULL) {
+    return 1;
+  }
+  return 0;
+}
+
+/**
+ * Move the current data pointer of a packet buffer contained in a netbuf
+ * to the beginning of the packet.
+ * The packet buffer itself is not modified.
+ *
+ * @param buf the netbuf to modify
+ */
+void
+netbuf_first(struct netbuf *buf)
+{
+  LWIP_ERROR("netbuf_free: invalid buf", (buf != NULL), return;);
+  buf->ptr = buf->p;
+}
+
+#endif /* LWIP_NETCONN */

src/lwip-1.4.1/src/api/netdb.c

@@ -0,0 +1,353 @@
+/**
+ * @file
+ * API functions for name resolving
+ *
+ */
+
+/*
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Simon Goldschmidt
+ *
+ */
+
+#include "lwip/netdb.h"
+
+#if LWIP_DNS && LWIP_SOCKET
+
+#include "lwip/err.h"
+#include "lwip/mem.h"
+#include "lwip/memp.h"
+#include "lwip/ip_addr.h"
+#include "lwip/api.h"
+#include "lwip/dns.h"
+
+#include <string.h>
+#include <stdlib.h>
+
+/** helper struct for gethostbyname_r to access the char* buffer */
+struct gethostbyname_r_helper {
+  ip_addr_t *addr_list[2];
+  ip_addr_t addr;
+  char *aliases;
+};
+
+/** h_errno is exported in netdb.h for access by applications. */
+#if LWIP_DNS_API_DECLARE_H_ERRNO
+int h_errno;
+#endif /* LWIP_DNS_API_DECLARE_H_ERRNO */
+
+/** define "hostent" variables storage: 0 if we use a static (but unprotected)
+ * set of variables for lwip_gethostbyname, 1 if we use a local storage */
+#ifndef LWIP_DNS_API_HOSTENT_STORAGE
+#define LWIP_DNS_API_HOSTENT_STORAGE 0
+#endif
+
+/** define "hostent" variables storage */
+#if LWIP_DNS_API_HOSTENT_STORAGE
+#define HOSTENT_STORAGE
+#else
+#define HOSTENT_STORAGE static
+#endif /* LWIP_DNS_API_STATIC_HOSTENT */
+
+/**
+ * Returns an entry containing addresses of address family AF_INET
+ * for the host with name name.
+ * Due to dns_gethostbyname limitations, only one address is returned.
+ *
+ * @param name the hostname to resolve
+ * @return an entry containing addresses of address family AF_INET
+ *         for the host with name name
+ */
+struct hostent*
+lwip_gethostbyname(const char *name)
+{
+  err_t err;
+  ip_addr_t addr;
+
+  /* buffer variables for lwip_gethostbyname() */
+  HOSTENT_STORAGE struct hostent s_hostent;
+  HOSTENT_STORAGE char *s_aliases;
+  HOSTENT_STORAGE ip_addr_t s_hostent_addr;
+  HOSTENT_STORAGE ip_addr_t *s_phostent_addr[2];
+
+  /* query host IP address */
+  err = netconn_gethostbyname(name, &addr);
+  if (err != ERR_OK) {
+    LWIP_DEBUGF(DNS_DEBUG, ("lwip_gethostbyname(%s) failed, err=%d\n", name, err));
+    h_errno = HOST_NOT_FOUND;
+    return NULL;
+  }
+
+  /* fill hostent */
+  s_hostent_addr = addr;
+  s_phostent_addr[0] = &s_hostent_addr;
+  s_phostent_addr[1] = NULL;
+  s_hostent.h_name = (char*)name;
+  s_hostent.h_aliases = &s_aliases;
+  s_hostent.h_addrtype = AF_INET;
+  s_hostent.h_length = sizeof(ip_addr_t);
+  s_hostent.h_addr_list = (char**)&s_phostent_addr;
+
+#if DNS_DEBUG
+  /* dump hostent */
+  LWIP_DEBUGF(DNS_DEBUG, ("hostent.h_name           == %s\n", s_hostent.h_name));
+  LWIP_DEBUGF(DNS_DEBUG, ("hostent.h_aliases        == %p\n", s_hostent.h_aliases));
+  if (s_hostent.h_aliases != NULL) {
+    u8_t idx;
+    for ( idx=0; s_hostent.h_aliases[idx]; idx++) {
+      LWIP_DEBUGF(DNS_DEBUG, ("hostent.h_aliases[%i]->   == %p\n", idx, s_hostent.h_aliases[idx]));
+      LWIP_DEBUGF(DNS_DEBUG, ("hostent.h_aliases[%i]->   == %s\n", idx, s_hostent.h_aliases[idx]));
+    }
+  }
+  LWIP_DEBUGF(DNS_DEBUG, ("hostent.h_addrtype       == %d\n", s_hostent.h_addrtype));
+  LWIP_DEBUGF(DNS_DEBUG, ("hostent.h_length         == %d\n", s_hostent.h_length));
+  LWIP_DEBUGF(DNS_DEBUG, ("hostent.h_addr_list      == %p\n", s_hostent.h_addr_list));
+  if (s_hostent.h_addr_list != NULL) {
+    u8_t idx;
+    for ( idx=0; s_hostent.h_addr_list[idx]; idx++) {
+      LWIP_DEBUGF(DNS_DEBUG, ("hostent.h_addr_list[%i]   == %p\n", idx, s_hostent.h_addr_list[idx]));
+      LWIP_DEBUGF(DNS_DEBUG, ("hostent.h_addr_list[%i]-> == %s\n", idx, ip_ntoa((ip_addr_t*)s_hostent.h_addr_list[idx])));
+    }
+  }
+#endif /* DNS_DEBUG */
+
+#if LWIP_DNS_API_HOSTENT_STORAGE
+  /* this function should return the "per-thread" hostent after copy from s_hostent */
+  return sys_thread_hostent(&s_hostent);
+#else
+  return &s_hostent;
+#endif /* LWIP_DNS_API_HOSTENT_STORAGE */
+}
+
+/**
+ * Thread-safe variant of lwip_gethostbyname: instead of using a static
+ * buffer, this function takes buffer and errno pointers as arguments
+ * and uses these for the result.
+ *
+ * @param name the hostname to resolve
+ * @param ret pre-allocated struct where to store the result
+ * @param buf pre-allocated buffer where to store additional data
+ * @param buflen the size of buf
+ * @param result pointer to a hostent pointer that is set to ret on success
+ *               and set to zero on error
+ * @param h_errnop pointer to an int where to store errors (instead of modifying
+ *                 the global h_errno)
+ * @return 0 on success, non-zero on error, additional error information
+ *         is stored in *h_errnop instead of h_errno to be thread-safe
+ */
+int
+lwip_gethostbyname_r(const char *name, struct hostent *ret, char *buf,
+                size_t buflen, struct hostent **result, int *h_errnop)
+{
+  err_t err;
+  struct gethostbyname_r_helper *h;
+  char *hostname;
+  size_t namelen;
+  int lh_errno;
+
+  if (h_errnop == NULL) {
+    /* ensure h_errnop is never NULL */
+    h_errnop = &lh_errno;
+  }
+
+  if (result == NULL) {
+    /* not all arguments given */
+    *h_errnop = EINVAL;
+    return -1;
+  }
+  /* first thing to do: set *result to nothing */
+  *result = NULL;
+  if ((name == NULL) || (ret == NULL) || (buf == NULL)) {
+    /* not all arguments given */
+    *h_errnop = EINVAL;
+    return -1;
+  }
+
+  namelen = strlen(name);
+  if (buflen < (sizeof(struct gethostbyname_r_helper) + namelen + 1 + (MEM_ALIGNMENT - 1))) {
+    /* buf can't hold the data needed + a copy of name */
+    *h_errnop = ERANGE;
+    return -1;
+  }
+
+  h = (struct gethostbyname_r_helper*)LWIP_MEM_ALIGN(buf);
+  hostname = ((char*)h) + sizeof(struct gethostbyname_r_helper);
+
+  /* query host IP address */
+  err = netconn_gethostbyname(name, &h->addr);
+  if (err != ERR_OK) {
+    LWIP_DEBUGF(DNS_DEBUG, ("lwip_gethostbyname(%s) failed, err=%d\n", name, err));
+    *h_errnop = HOST_NOT_FOUND;
+    return -1;
+  }
+
+  /* copy the hostname into buf */
+  MEMCPY(hostname, name, namelen);
+  hostname[namelen] = 0;
+
+  /* fill hostent */
+  h->addr_list[0] = &h->addr;
+  h->addr_list[1] = NULL;
+  h->aliases = NULL;
+  ret->h_name = hostname;
+  ret->h_aliases = &h->aliases;
+  ret->h_addrtype = AF_INET;
+  ret->h_length = sizeof(ip_addr_t);
+  ret->h_addr_list = (char**)&h->addr_list;
+
+  /* set result != NULL */
+  *result = ret;
+
+  /* return success */
+  return 0;
+}
+
+/**
+ * Frees one or more addrinfo structures returned by getaddrinfo(), along with
+ * any additional storage associated with those structures. If the ai_next field
+ * of the structure is not null, the entire list of structures is freed.
+ *
+ * @param ai struct addrinfo to free
+ */
+void
+lwip_freeaddrinfo(struct addrinfo *ai)
+{
+  struct addrinfo *next;
+
+  while (ai != NULL) {
+    next = ai->ai_next;
+    memp_free(MEMP_NETDB, ai);
+    ai = next;
+  }
+}
+
+/**
+ * Translates the name of a service location (for example, a host name) and/or
+ * a service name and returns a set of socket addresses and associated
+ * information to be used in creating a socket with which to address the
+ * specified service.
+ * Memory for the result is allocated internally and must be freed by calling
+ * lwip_freeaddrinfo()!
+ *
+ * Due to a limitation in dns_gethostbyname, only the first address of a
+ * host is returned.
+ * Also, service names are not supported (only port numbers)!
+ *
+ * @param nodename descriptive name or address string of the host
+ *                 (may be NULL -> local address)
+ * @param servname port number as string of NULL 
+ * @param hints structure containing input values that set socktype and protocol
+ * @param res pointer to a pointer where to store the result (set to NULL on failure)
+ * @return 0 on success, non-zero on failure
+ */
+int
+lwip_getaddrinfo(const char *nodename, const char *servname,
+       const struct addrinfo *hints, struct addrinfo **res)
+{
+  err_t err;
+  ip_addr_t addr;
+  struct addrinfo *ai;
+  struct sockaddr_in *sa = NULL;
+  int port_nr = 0;
+  size_t total_size;
+  size_t namelen = 0;
+
+  if (res == NULL) {
+    return EAI_FAIL;
+  }
+  *res = NULL;
+  if ((nodename == NULL) && (servname == NULL)) {
+    return EAI_NONAME;
+  }
+
+  if (servname != NULL) {
+    /* service name specified: convert to port number
+     * @todo?: currently, only ASCII integers (port numbers) are supported! */
+    port_nr = atoi(servname);
+    if ((port_nr <= 0) || (port_nr > 0xffff)) {
+      return EAI_SERVICE;
+    }
+  }
+
+  if (nodename != NULL) {
+    /* service location specified, try to resolve */
+    err = netconn_gethostbyname(nodename, &addr);
+    if (err != ERR_OK) {
+      return EAI_FAIL;
+    }
+  } else {
+    /* service location specified, use loopback address */
+    ip_addr_set_loopback(&addr);
+  }
+
+  total_size = sizeof(struct addrinfo) + sizeof(struct sockaddr_in);
+  if (nodename != NULL) {
+    namelen = strlen(nodename);
+    LWIP_ASSERT("namelen is too long", (namelen + 1) <= (mem_size_t)-1);
+    total_size += namelen + 1;
+  }
+  /* If this fails, please report to lwip-devel! :-) */
+  LWIP_ASSERT("total_size <= NETDB_ELEM_SIZE: please report this!",
+    total_size <= NETDB_ELEM_SIZE);
+  ai = (struct addrinfo *)memp_malloc(MEMP_NETDB);
+  if (ai == NULL) {
+    goto memerr;
+  }
+  memset(ai, 0, total_size);
+  sa = (struct sockaddr_in*)((u8_t*)ai + sizeof(struct addrinfo));
+  /* set up sockaddr */
+  inet_addr_from_ipaddr(&sa->sin_addr, &addr);
+  sa->sin_family = AF_INET;
+  sa->sin_len = sizeof(struct sockaddr_in);
+  sa->sin_port = htons((u16_t)port_nr);
+
+  /* set up addrinfo */
+  ai->ai_family = AF_INET;
+  if (hints != NULL) {
+    /* copy socktype & protocol from hints if specified */
+    ai->ai_socktype = hints->ai_socktype;
+    ai->ai_protocol = hints->ai_protocol;
+  }
+  if (nodename != NULL) {
+    /* copy nodename to canonname if specified */
+    ai->ai_canonname = ((char*)ai + sizeof(struct addrinfo) + sizeof(struct sockaddr_in));
+    MEMCPY(ai->ai_canonname, nodename, namelen);
+    ai->ai_canonname[namelen] = 0;
+  }
+  ai->ai_addrlen = sizeof(struct sockaddr_in);
+  ai->ai_addr = (struct sockaddr*)sa;
+
+  *res = ai;
+
+  return 0;
+memerr:
+  if (ai != NULL) {
+    memp_free(MEMP_NETDB, ai);
+  }
+  return EAI_MEMORY;
+}
+
+#endif /* LWIP_DNS && LWIP_SOCKET */

src/lwip-1.4.1/src/api/netifapi.c

@@ -0,0 +1,160 @@
+/**
+ * @file
+ * Network Interface Sequential API module
+ *
+ */
+
+/*
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_NETIF_API /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/netifapi.h"
+#include "lwip/tcpip.h"
+
+/**
+ * Call netif_add() inside the tcpip_thread context.
+ */
+void
+do_netifapi_netif_add(struct netifapi_msg_msg *msg)
+{
+  if (!netif_add( msg->netif,
+                  msg->msg.add.ipaddr,
+                  msg->msg.add.netmask,
+                  msg->msg.add.gw,
+                  msg->msg.add.state,
+                  msg->msg.add.init,
+                  msg->msg.add.input)) {
+    msg->err = ERR_IF;
+  } else {
+    msg->err = ERR_OK;
+  }
+  TCPIP_NETIFAPI_ACK(msg);
+}
+
+/**
+ * Call netif_set_addr() inside the tcpip_thread context.
+ */
+void
+do_netifapi_netif_set_addr(struct netifapi_msg_msg *msg)
+{
+  netif_set_addr( msg->netif,
+                  msg->msg.add.ipaddr,
+                  msg->msg.add.netmask,
+                  msg->msg.add.gw);
+  msg->err = ERR_OK;
+  TCPIP_NETIFAPI_ACK(msg);
+}
+
+/**
+ * Call the "errtfunc" (or the "voidfunc" if "errtfunc" is NULL) inside the
+ * tcpip_thread context.
+ */
+void
+do_netifapi_netif_common(struct netifapi_msg_msg *msg)
+{
+  if (msg->msg.common.errtfunc != NULL) {
+    msg->err = msg->msg.common.errtfunc(msg->netif);
+  } else {
+    msg->err = ERR_OK;
+    msg->msg.common.voidfunc(msg->netif);
+  }
+  TCPIP_NETIFAPI_ACK(msg);
+}
+
+/**
+ * Call netif_add() in a thread-safe way by running that function inside the
+ * tcpip_thread context.
+ *
+ * @note for params @see netif_add()
+ */
+err_t
+netifapi_netif_add(struct netif *netif,
+                   ip_addr_t *ipaddr,
+                   ip_addr_t *netmask,
+                   ip_addr_t *gw,
+                   void *state,
+                   netif_init_fn init,
+                   netif_input_fn input)
+{
+  struct netifapi_msg msg;
+  msg.function = do_netifapi_netif_add;
+  msg.msg.netif = netif;
+  msg.msg.msg.add.ipaddr  = ipaddr;
+  msg.msg.msg.add.netmask = netmask;
+  msg.msg.msg.add.gw      = gw;
+  msg.msg.msg.add.state   = state;
+  msg.msg.msg.add.init    = init;
+  msg.msg.msg.add.input   = input;
+  TCPIP_NETIFAPI(&msg);
+  return msg.msg.err;
+}
+
+/**
+ * Call netif_set_addr() in a thread-safe way by running that function inside the
+ * tcpip_thread context.
+ *
+ * @note for params @see netif_set_addr()
+ */
+err_t
+netifapi_netif_set_addr(struct netif *netif,
+                        ip_addr_t *ipaddr,
+                        ip_addr_t *netmask,
+                        ip_addr_t *gw)
+{
+  struct netifapi_msg msg;
+  msg.function = do_netifapi_netif_set_addr;
+  msg.msg.netif = netif;
+  msg.msg.msg.add.ipaddr  = ipaddr;
+  msg.msg.msg.add.netmask = netmask;
+  msg.msg.msg.add.gw      = gw;
+  TCPIP_NETIFAPI(&msg);
+  return msg.msg.err;
+}
+
+/**
+ * call the "errtfunc" (or the "voidfunc" if "errtfunc" is NULL) in a thread-safe
+ * way by running that function inside the tcpip_thread context.
+ *
+ * @note use only for functions where there is only "netif" parameter.
+ */
+err_t
+netifapi_netif_common(struct netif *netif, netifapi_void_fn voidfunc,
+                       netifapi_errt_fn errtfunc)
+{
+  struct netifapi_msg msg;
+  msg.function = do_netifapi_netif_common;
+  msg.msg.netif = netif;
+  msg.msg.msg.common.voidfunc = voidfunc;
+  msg.msg.msg.common.errtfunc = errtfunc;
+  TCPIP_NETIFAPI(&msg);
+  return msg.msg.err;
+}
+
+#endif /* LWIP_NETIF_API */

src/lwip-1.4.1/src/api/tcpip.c

@@ -0,0 +1,511 @@
+/**
+ * @file
+ * Sequential API Main thread module
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if !NO_SYS /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/sys.h"
+#include "lwip/memp.h"
+#include "lwip/mem.h"
+#include "lwip/pbuf.h"
+#include "lwip/tcpip.h"
+#include "lwip/init.h"
+#include "netif/etharp.h"
+#include "netif/ppp_oe.h"
+
+/* global variables */
+static tcpip_init_done_fn tcpip_init_done;
+static void *tcpip_init_done_arg;
+static sys_mbox_t mbox;
+
+#if LWIP_TCPIP_CORE_LOCKING
+/** The global semaphore to lock the stack. */
+sys_mutex_t lock_tcpip_core;
+#endif /* LWIP_TCPIP_CORE_LOCKING */
+
+
+/**
+ * The main lwIP thread. This thread has exclusive access to lwIP core functions
+ * (unless access to them is not locked). Other threads communicate with this
+ * thread using message boxes.
+ *
+ * It also starts all the timers to make sure they are running in the right
+ * thread context.
+ *
+ * @param arg unused argument
+ */
+static void
+tcpip_thread(void *arg)
+{
+  struct tcpip_msg *msg;
+  LWIP_UNUSED_ARG(arg);
+
+  if (tcpip_init_done != NULL) {
+    tcpip_init_done(tcpip_init_done_arg);
+  }
+
+  LOCK_TCPIP_CORE();
+  while (1) {                          /* MAIN Loop */
+    UNLOCK_TCPIP_CORE();
+    LWIP_TCPIP_THREAD_ALIVE();
+    /* wait for a message, timeouts are processed while waiting */
+    sys_timeouts_mbox_fetch(&mbox, (void **)&msg);
+    LOCK_TCPIP_CORE();
+    switch (msg->type) {
+#if LWIP_NETCONN
+    case TCPIP_MSG_API:
+      LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: API message %p\n", (void *)msg));
+      msg->msg.apimsg->function(&(msg->msg.apimsg->msg));
+      break;
+#endif /* LWIP_NETCONN */
+
+#if !LWIP_TCPIP_CORE_LOCKING_INPUT
+    case TCPIP_MSG_INPKT:
+      LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: PACKET %p\n", (void *)msg));
+#if LWIP_ETHERNET
+      if (msg->msg.inp.netif->flags & (NETIF_FLAG_ETHARP | NETIF_FLAG_ETHERNET)) {
+        ethernet_input(msg->msg.inp.p, msg->msg.inp.netif);
+      } else
+#endif /* LWIP_ETHERNET */
+      {
+        ip_input(msg->msg.inp.p, msg->msg.inp.netif);
+      }
+      memp_free(MEMP_TCPIP_MSG_INPKT, msg);
+      break;
+#endif /* LWIP_TCPIP_CORE_LOCKING_INPUT */
+
+#if LWIP_NETIF_API
+    case TCPIP_MSG_NETIFAPI:
+      LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: Netif API message %p\n", (void *)msg));
+      msg->msg.netifapimsg->function(&(msg->msg.netifapimsg->msg));
+      break;
+#endif /* LWIP_NETIF_API */
+
+#if LWIP_TCPIP_TIMEOUT
+    case TCPIP_MSG_TIMEOUT:
+      LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: TIMEOUT %p\n", (void *)msg));
+      sys_timeout(msg->msg.tmo.msecs, msg->msg.tmo.h, msg->msg.tmo.arg);
+      memp_free(MEMP_TCPIP_MSG_API, msg);
+      break;
+    case TCPIP_MSG_UNTIMEOUT:
+      LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: UNTIMEOUT %p\n", (void *)msg));
+      sys_untimeout(msg->msg.tmo.h, msg->msg.tmo.arg);
+      memp_free(MEMP_TCPIP_MSG_API, msg);
+      break;
+#endif /* LWIP_TCPIP_TIMEOUT */
+
+    case TCPIP_MSG_CALLBACK:
+      LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: CALLBACK %p\n", (void *)msg));
+      msg->msg.cb.function(msg->msg.cb.ctx);
+      memp_free(MEMP_TCPIP_MSG_API, msg);
+      break;
+
+    case TCPIP_MSG_CALLBACK_STATIC:
+      LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: CALLBACK_STATIC %p\n", (void *)msg));
+      msg->msg.cb.function(msg->msg.cb.ctx);
+      break;
+
+    default:
+      LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: invalid message: %d\n", msg->type));
+      LWIP_ASSERT("tcpip_thread: invalid message", 0);
+      break;
+    }
+  }
+}
+
+/**
+ * Pass a received packet to tcpip_thread for input processing
+ *
+ * @param p the received packet, p->payload pointing to the Ethernet header or
+ *          to an IP header (if inp doesn't have NETIF_FLAG_ETHARP or
+ *          NETIF_FLAG_ETHERNET flags)
+ * @param inp the network interface on which the packet was received
+ */
+err_t
+tcpip_input(struct pbuf *p, struct netif *inp)
+{
+#if LWIP_TCPIP_CORE_LOCKING_INPUT
+  err_t ret;
+  LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_input: PACKET %p/%p\n", (void *)p, (void *)inp));
+  LOCK_TCPIP_CORE();
+#if LWIP_ETHERNET
+  if (inp->flags & (NETIF_FLAG_ETHARP | NETIF_FLAG_ETHERNET)) {
+    ret = ethernet_input(p, inp);
+  } else
+#endif /* LWIP_ETHERNET */
+  {
+    ret = ip_input(p, inp);
+  }
+  UNLOCK_TCPIP_CORE();
+  return ret;
+#else /* LWIP_TCPIP_CORE_LOCKING_INPUT */
+  struct tcpip_msg *msg;
+
+  if (!sys_mbox_valid(&mbox)) {
+    return ERR_VAL;
+  }
+  msg = (struct tcpip_msg *)memp_malloc(MEMP_TCPIP_MSG_INPKT);
+  if (msg == NULL) {
+    return ERR_MEM;
+  }
+
+  msg->type = TCPIP_MSG_INPKT;
+  msg->msg.inp.p = p;
+  msg->msg.inp.netif = inp;
+  if (sys_mbox_trypost(&mbox, msg) != ERR_OK) {
+    memp_free(MEMP_TCPIP_MSG_INPKT, msg);
+    return ERR_MEM;
+  }
+  return ERR_OK;
+#endif /* LWIP_TCPIP_CORE_LOCKING_INPUT */
+}
+
+/**
+ * Call a specific function in the thread context of
+ * tcpip_thread for easy access synchronization.
+ * A function called in that way may access lwIP core code
+ * without fearing concurrent access.
+ *
+ * @param f the function to call
+ * @param ctx parameter passed to f
+ * @param block 1 to block until the request is posted, 0 to non-blocking mode
+ * @return ERR_OK if the function was called, another err_t if not
+ */
+err_t
+tcpip_callback_with_block(tcpip_callback_fn function, void *ctx, u8_t block)
+{
+  struct tcpip_msg *msg;
+
+  if (sys_mbox_valid(&mbox)) {
+    msg = (struct tcpip_msg *)memp_malloc(MEMP_TCPIP_MSG_API);
+    if (msg == NULL) {
+      return ERR_MEM;
+    }
+
+    msg->type = TCPIP_MSG_CALLBACK;
+    msg->msg.cb.function = function;
+    msg->msg.cb.ctx = ctx;
+    if (block) {
+      sys_mbox_post(&mbox, msg);
+    } else {
+      if (sys_mbox_trypost(&mbox, msg) != ERR_OK) {
+        memp_free(MEMP_TCPIP_MSG_API, msg);
+        return ERR_MEM;
+      }
+    }
+    return ERR_OK;
+  }
+  return ERR_VAL;
+}
+
+#if LWIP_TCPIP_TIMEOUT
+/**
+ * call sys_timeout in tcpip_thread
+ *
+ * @param msec time in milliseconds for timeout
+ * @param h function to be called on timeout
+ * @param arg argument to pass to timeout function h
+ * @return ERR_MEM on memory error, ERR_OK otherwise
+ */
+err_t
+tcpip_timeout(u32_t msecs, sys_timeout_handler h, void *arg)
+{
+  struct tcpip_msg *msg;
+
+  if (sys_mbox_valid(&mbox)) {
+    msg = (struct tcpip_msg *)memp_malloc(MEMP_TCPIP_MSG_API);
+    if (msg == NULL) {
+      return ERR_MEM;
+    }
+
+    msg->type = TCPIP_MSG_TIMEOUT;
+    msg->msg.tmo.msecs = msecs;
+    msg->msg.tmo.h = h;
+    msg->msg.tmo.arg = arg;
+    sys_mbox_post(&mbox, msg);
+    return ERR_OK;
+  }
+  return ERR_VAL;
+}
+
+/**
+ * call sys_untimeout in tcpip_thread
+ *
+ * @param msec time in milliseconds for timeout
+ * @param h function to be called on timeout
+ * @param arg argument to pass to timeout function h
+ * @return ERR_MEM on memory error, ERR_OK otherwise
+ */
+err_t
+tcpip_untimeout(sys_timeout_handler h, void *arg)
+{
+  struct tcpip_msg *msg;
+
+  if (sys_mbox_valid(&mbox)) {
+    msg = (struct tcpip_msg *)memp_malloc(MEMP_TCPIP_MSG_API);
+    if (msg == NULL) {
+      return ERR_MEM;
+    }
+
+    msg->type = TCPIP_MSG_UNTIMEOUT;
+    msg->msg.tmo.h = h;
+    msg->msg.tmo.arg = arg;
+    sys_mbox_post(&mbox, msg);
+    return ERR_OK;
+  }
+  return ERR_VAL;
+}
+#endif /* LWIP_TCPIP_TIMEOUT */
+
+#if LWIP_NETCONN
+/**
+ * Call the lower part of a netconn_* function
+ * This function is then running in the thread context
+ * of tcpip_thread and has exclusive access to lwIP core code.
+ *
+ * @param apimsg a struct containing the function to call and its parameters
+ * @return ERR_OK if the function was called, another err_t if not
+ */
+err_t
+tcpip_apimsg(struct api_msg *apimsg)
+{
+  struct tcpip_msg msg;
+#ifdef LWIP_DEBUG
+  /* catch functions that don't set err */
+  apimsg->msg.err = ERR_VAL;
+#endif
+  
+  if (sys_mbox_valid(&mbox)) {
+    msg.type = TCPIP_MSG_API;
+    msg.msg.apimsg = apimsg;
+    sys_mbox_post(&mbox, &msg);
+    sys_arch_sem_wait(&apimsg->msg.conn->op_completed, 0);
+    return apimsg->msg.err;
+  }
+  return ERR_VAL;
+}
+
+#if LWIP_TCPIP_CORE_LOCKING
+/**
+ * Call the lower part of a netconn_* function
+ * This function has exclusive access to lwIP core code by locking it
+ * before the function is called.
+ *
+ * @param apimsg a struct containing the function to call and its parameters
+ * @return ERR_OK (only for compatibility fo tcpip_apimsg())
+ */
+err_t
+tcpip_apimsg_lock(struct api_msg *apimsg)
+{
+#ifdef LWIP_DEBUG
+  /* catch functions that don't set err */
+  apimsg->msg.err = ERR_VAL;
+#endif
+
+  LOCK_TCPIP_CORE();
+  apimsg->function(&(apimsg->msg));
+  UNLOCK_TCPIP_CORE();
+  return apimsg->msg.err;
+
+}
+#endif /* LWIP_TCPIP_CORE_LOCKING */
+#endif /* LWIP_NETCONN */
+
+#if LWIP_NETIF_API
+#if !LWIP_TCPIP_CORE_LOCKING
+/**
+ * Much like tcpip_apimsg, but calls the lower part of a netifapi_*
+ * function.
+ *
+ * @param netifapimsg a struct containing the function to call and its parameters
+ * @return error code given back by the function that was called
+ */
+err_t
+tcpip_netifapi(struct netifapi_msg* netifapimsg)
+{
+  struct tcpip_msg msg;
+  
+  if (sys_mbox_valid(&mbox)) {
+    err_t err = sys_sem_new(&netifapimsg->msg.sem, 0);
+    if (err != ERR_OK) {
+      netifapimsg->msg.err = err;
+      return err;
+    }
+    
+    msg.type = TCPIP_MSG_NETIFAPI;
+    msg.msg.netifapimsg = netifapimsg;
+    sys_mbox_post(&mbox, &msg);
+    sys_sem_wait(&netifapimsg->msg.sem);
+    sys_sem_free(&netifapimsg->msg.sem);
+    return netifapimsg->msg.err;
+  }
+  return ERR_VAL;
+}
+#else /* !LWIP_TCPIP_CORE_LOCKING */
+/**
+ * Call the lower part of a netifapi_* function
+ * This function has exclusive access to lwIP core code by locking it
+ * before the function is called.
+ *
+ * @param netifapimsg a struct containing the function to call and its parameters
+ * @return ERR_OK (only for compatibility fo tcpip_netifapi())
+ */
+err_t
+tcpip_netifapi_lock(struct netifapi_msg* netifapimsg)
+{
+  LOCK_TCPIP_CORE();  
+  netifapimsg->function(&(netifapimsg->msg));
+  UNLOCK_TCPIP_CORE();
+  return netifapimsg->msg.err;
+}
+#endif /* !LWIP_TCPIP_CORE_LOCKING */
+#endif /* LWIP_NETIF_API */
+
+/**
+ * Allocate a structure for a static callback message and initialize it.
+ * This is intended to be used to send "static" messages from interrupt context.
+ *
+ * @param function the function to call
+ * @param ctx parameter passed to function
+ * @return a struct pointer to pass to tcpip_trycallback().
+ */
+struct tcpip_callback_msg* tcpip_callbackmsg_new(tcpip_callback_fn function, void *ctx)
+{
+  struct tcpip_msg *msg = (struct tcpip_msg *)memp_malloc(MEMP_TCPIP_MSG_API);
+  if (msg == NULL) {
+    return NULL;
+  }
+  msg->type = TCPIP_MSG_CALLBACK_STATIC;
+  msg->msg.cb.function = function;
+  msg->msg.cb.ctx = ctx;
+  return (struct tcpip_callback_msg*)msg;
+}
+
+/**
+ * Free a callback message allocated by tcpip_callbackmsg_new().
+ *
+ * @param msg the message to free
+ */
+void tcpip_callbackmsg_delete(struct tcpip_callback_msg* msg)
+{
+  memp_free(MEMP_TCPIP_MSG_API, msg);
+}
+
+/**
+ * Try to post a callback-message to the tcpip_thread mbox
+ * This is intended to be used to send "static" messages from interrupt context.
+ *
+ * @param msg pointer to the message to post
+ * @return sys_mbox_trypost() return code
+ */
+err_t
+tcpip_trycallback(struct tcpip_callback_msg* msg)
+{
+  if (!sys_mbox_valid(&mbox)) {
+    return ERR_VAL;
+  }
+  return sys_mbox_trypost(&mbox, msg);
+}
+
+/**
+ * Initialize this module:
+ * - initialize all sub modules
+ * - start the tcpip_thread
+ *
+ * @param initfunc a function to call when tcpip_thread is running and finished initializing
+ * @param arg argument to pass to initfunc
+ */
+void
+tcpip_init(tcpip_init_done_fn initfunc, void *arg)
+{
+  lwip_init();
+
+  tcpip_init_done = initfunc;
+  tcpip_init_done_arg = arg;
+  if(sys_mbox_new(&mbox, TCPIP_MBOX_SIZE) != ERR_OK) {
+    LWIP_ASSERT("failed to create tcpip_thread mbox", 0);
+  }
+#if LWIP_TCPIP_CORE_LOCKING
+  if(sys_mutex_new(&lock_tcpip_core) != ERR_OK) {
+    LWIP_ASSERT("failed to create lock_tcpip_core", 0);
+  }
+#endif /* LWIP_TCPIP_CORE_LOCKING */
+
+  sys_thread_new(TCPIP_THREAD_NAME, tcpip_thread, NULL, TCPIP_THREAD_STACKSIZE, TCPIP_THREAD_PRIO);
+}
+
+/**
+ * Simple callback function used with tcpip_callback to free a pbuf
+ * (pbuf_free has a wrong signature for tcpip_callback)
+ *
+ * @param p The pbuf (chain) to be dereferenced.
+ */
+static void
+pbuf_free_int(void *p)
+{
+  struct pbuf *q = (struct pbuf *)p;
+  pbuf_free(q);
+}
+
+/**
+ * A simple wrapper function that allows you to free a pbuf from interrupt context.
+ *
+ * @param p The pbuf (chain) to be dereferenced.
+ * @return ERR_OK if callback could be enqueued, an err_t if not
+ */
+err_t
+pbuf_free_callback(struct pbuf *p)
+{
+  return tcpip_callback_with_block(pbuf_free_int, p, 0);
+}
+
+/**
+ * A simple wrapper function that allows you to free heap memory from
+ * interrupt context.
+ *
+ * @param m the heap memory to free
+ * @return ERR_OK if callback could be enqueued, an err_t if not
+ */
+err_t
+mem_free_callback(void *m)
+{
+  return tcpip_callback_with_block(mem_free, m, 0);
+}
+
+#endif /* !NO_SYS */

src/lwip-1.4.1/src/core/def.c

@@ -0,0 +1,108 @@
+/**
+ * @file
+ * Common functions used throughout the stack.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Simon Goldschmidt
+ *
+ */
+
+#include "lwip/opt.h"
+#include "lwip/def.h"
+
+/**
+ * These are reference implementations of the byte swapping functions.
+ * Again with the aim of being simple, correct and fully portable.
+ * Byte swapping is the second thing you would want to optimize. You will
+ * need to port it to your architecture and in your cc.h:
+ * 
+ * #define LWIP_PLATFORM_BYTESWAP 1
+ * #define LWIP_PLATFORM_HTONS(x) <your_htons>
+ * #define LWIP_PLATFORM_HTONL(x) <your_htonl>
+ *
+ * Note ntohs() and ntohl() are merely references to the htonx counterparts.
+ */
+
+#if (LWIP_PLATFORM_BYTESWAP == 0) && (BYTE_ORDER == LITTLE_ENDIAN)
+
+/**
+ * Convert an u16_t from host- to network byte order.
+ *
+ * @param n u16_t in host byte order
+ * @return n in network byte order
+ */
+u16_t
+lwip_htons(u16_t n)
+{
+  return ((n & 0xff) << 8) | ((n & 0xff00) >> 8);
+}
+
+/**
+ * Convert an u16_t from network- to host byte order.
+ *
+ * @param n u16_t in network byte order
+ * @return n in host byte order
+ */
+u16_t
+lwip_ntohs(u16_t n)
+{
+  return lwip_htons(n);
+}
+
+/**
+ * Convert an u32_t from host- to network byte order.
+ *
+ * @param n u32_t in host byte order
+ * @return n in network byte order
+ */
+u32_t
+lwip_htonl(u32_t n)
+{
+  return ((n & 0xff) << 24) |
+    ((n & 0xff00) << 8) |
+    ((n & 0xff0000UL) >> 8) |
+    ((n & 0xff000000UL) >> 24);
+}
+
+/**
+ * Convert an u32_t from network- to host byte order.
+ *
+ * @param n u32_t in network byte order
+ * @return n in host byte order
+ */
+u32_t
+lwip_ntohl(u32_t n)
+{
+  return lwip_htonl(n);
+}
+
+#endif /* (LWIP_PLATFORM_BYTESWAP == 0) && (BYTE_ORDER == LITTLE_ENDIAN) */

src/lwip-1.4.1/src/core/dns.c

@@ -0,0 +1,970 @@
+/**
+ * @file
+ * DNS - host name to IP address resolver.
+ *
+ */
+
+/**
+
+ * This file implements a DNS host name to IP address resolver.
+
+ * Port to lwIP from uIP
+ * by Jim Pettinato April 2007
+
+ * uIP version Copyright (c) 2002-2003, Adam Dunkels.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ *    products derived from this software without specific prior
+ *    written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
+ * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
+ * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *
+ * DNS.C
+ *
+ * The lwIP DNS resolver functions are used to lookup a host name and
+ * map it to a numerical IP address. It maintains a list of resolved
+ * hostnames that can be queried with the dns_lookup() function.
+ * New hostnames can be resolved using the dns_query() function.
+ *
+ * The lwIP version of the resolver also adds a non-blocking version of
+ * gethostbyname() that will work with a raw API application. This function
+ * checks for an IP address string first and converts it if it is valid.
+ * gethostbyname() then does a dns_lookup() to see if the name is 
+ * already in the table. If so, the IP is returned. If not, a query is 
+ * issued and the function returns with a ERR_INPROGRESS status. The app
+ * using the dns client must then go into a waiting state.
+ *
+ * Once a hostname has been resolved (or found to be non-existent),
+ * the resolver code calls a specified callback function (which 
+ * must be implemented by the module that uses the resolver).
+ */
+
+/*-----------------------------------------------------------------------------
+ * RFC 1035 - Domain names - implementation and specification
+ * RFC 2181 - Clarifications to the DNS Specification
+ *----------------------------------------------------------------------------*/
+
+/** @todo: define good default values (rfc compliance) */
+/** @todo: improve answer parsing, more checkings... */
+/** @todo: check RFC1035 - 7.3. Processing responses */
+
+/*-----------------------------------------------------------------------------
+ * Includes
+ *----------------------------------------------------------------------------*/
+
+#include "lwip/opt.h"
+
+#if LWIP_DNS /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/udp.h"
+#include "lwip/mem.h"
+#include "lwip/memp.h"
+#include "lwip/dns.h"
+
+#include <string.h>
+
+/** DNS server IP address */
+#ifndef DNS_SERVER_ADDRESS
+#define DNS_SERVER_ADDRESS(ipaddr)        (ip4_addr_set_u32(ipaddr, ipaddr_addr("208.67.222.222"))) /* resolver1.opendns.com */
+#endif
+
+/** DNS server port address */
+#ifndef DNS_SERVER_PORT
+#define DNS_SERVER_PORT           53
+#endif
+
+/** DNS maximum number of retries when asking for a name, before "timeout". */
+#ifndef DNS_MAX_RETRIES
+#define DNS_MAX_RETRIES           4
+#endif
+
+/** DNS resource record max. TTL (one week as default) */
+#ifndef DNS_MAX_TTL
+#define DNS_MAX_TTL               604800
+#endif
+
+/* DNS protocol flags */
+#define DNS_FLAG1_RESPONSE        0x80
+#define DNS_FLAG1_OPCODE_STATUS   0x10
+#define DNS_FLAG1_OPCODE_INVERSE  0x08
+#define DNS_FLAG1_OPCODE_STANDARD 0x00
+#define DNS_FLAG1_AUTHORATIVE     0x04
+#define DNS_FLAG1_TRUNC           0x02
+#define DNS_FLAG1_RD              0x01
+#define DNS_FLAG2_RA              0x80
+#define DNS_FLAG2_ERR_MASK        0x0f
+#define DNS_FLAG2_ERR_NONE        0x00
+#define DNS_FLAG2_ERR_NAME        0x03
+
+/* DNS protocol states */
+#define DNS_STATE_UNUSED          0
+#define DNS_STATE_NEW             1
+#define DNS_STATE_ASKING          2
+#define DNS_STATE_DONE            3
+
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+/** DNS message header */
+struct dns_hdr {
+  PACK_STRUCT_FIELD(u16_t id);
+  PACK_STRUCT_FIELD(u8_t flags1);
+  PACK_STRUCT_FIELD(u8_t flags2);
+  PACK_STRUCT_FIELD(u16_t numquestions);
+  PACK_STRUCT_FIELD(u16_t numanswers);
+  PACK_STRUCT_FIELD(u16_t numauthrr);
+  PACK_STRUCT_FIELD(u16_t numextrarr);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+#define SIZEOF_DNS_HDR 12
+
+/** DNS query message structure.
+    No packing needed: only used locally on the stack. */
+struct dns_query {
+  /* DNS query record starts with either a domain name or a pointer
+     to a name already present somewhere in the packet. */
+  u16_t type;
+  u16_t cls;
+};
+#define SIZEOF_DNS_QUERY 4
+
+/** DNS answer message structure.
+    No packing needed: only used locally on the stack. */
+struct dns_answer {
+  /* DNS answer record starts with either a domain name or a pointer
+     to a name already present somewhere in the packet. */
+  u16_t type;
+  u16_t cls;
+  u32_t ttl;
+  u16_t len;
+};
+#define SIZEOF_DNS_ANSWER 10
+
+/** DNS table entry */
+struct dns_table_entry {
+  u8_t  state;
+  u8_t  numdns;
+  u8_t  tmr;
+  u8_t  retries;
+  u8_t  seqno;
+  u8_t  err;
+  u32_t ttl;
+  char name[DNS_MAX_NAME_LENGTH];
+  ip_addr_t ipaddr;
+  /* pointer to callback on DNS query done */
+  dns_found_callback found;
+  void *arg;
+};
+
+#if DNS_LOCAL_HOSTLIST
+
+#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC
+/** Local host-list. For hostnames in this list, no
+ *  external name resolution is performed */
+static struct local_hostlist_entry *local_hostlist_dynamic;
+#else /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+
+/** Defining this allows the local_hostlist_static to be placed in a different
+ * linker section (e.g. FLASH) */
+#ifndef DNS_LOCAL_HOSTLIST_STORAGE_PRE
+#define DNS_LOCAL_HOSTLIST_STORAGE_PRE static
+#endif /* DNS_LOCAL_HOSTLIST_STORAGE_PRE */
+/** Defining this allows the local_hostlist_static to be placed in a different
+ * linker section (e.g. FLASH) */
+#ifndef DNS_LOCAL_HOSTLIST_STORAGE_POST
+#define DNS_LOCAL_HOSTLIST_STORAGE_POST
+#endif /* DNS_LOCAL_HOSTLIST_STORAGE_POST */
+DNS_LOCAL_HOSTLIST_STORAGE_PRE struct local_hostlist_entry local_hostlist_static[]
+  DNS_LOCAL_HOSTLIST_STORAGE_POST = DNS_LOCAL_HOSTLIST_INIT;
+
+#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+
+static void dns_init_local();
+#endif /* DNS_LOCAL_HOSTLIST */
+
+
+/* forward declarations */
+static void dns_recv(void *s, struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *addr, u16_t port);
+static void dns_check_entries(void);
+
+/*-----------------------------------------------------------------------------
+ * Globales
+ *----------------------------------------------------------------------------*/
+
+/* DNS variables */
+static struct udp_pcb        *dns_pcb;
+static u8_t                   dns_seqno;
+static struct dns_table_entry dns_table[DNS_TABLE_SIZE];
+static ip_addr_t              dns_servers[DNS_MAX_SERVERS];
+/** Contiguous buffer for processing responses */
+static u8_t                   dns_payload_buffer[LWIP_MEM_ALIGN_BUFFER(DNS_MSG_SIZE)];
+static u8_t*                  dns_payload;
+
+/**
+ * Initialize the resolver: set up the UDP pcb and configure the default server
+ * (DNS_SERVER_ADDRESS).
+ */
+void
+dns_init()
+{
+  ip_addr_t dnsserver;
+
+  dns_payload = (u8_t *)LWIP_MEM_ALIGN(dns_payload_buffer);
+  
+  /* initialize default DNS server address */
+  DNS_SERVER_ADDRESS(&dnsserver);
+
+  LWIP_DEBUGF(DNS_DEBUG, ("dns_init: initializing\n"));
+
+  /* if dns client not yet initialized... */
+  if (dns_pcb == NULL) {
+    dns_pcb = udp_new();
+
+    if (dns_pcb != NULL) {
+      /* initialize DNS table not needed (initialized to zero since it is a
+       * global variable) */
+      LWIP_ASSERT("For implicit initialization to work, DNS_STATE_UNUSED needs to be 0",
+        DNS_STATE_UNUSED == 0);
+
+      /* initialize DNS client */
+      udp_bind(dns_pcb, IP_ADDR_ANY, 0);
+      udp_recv(dns_pcb, dns_recv, NULL);
+
+      /* initialize default DNS primary server */
+      dns_setserver(0, &dnsserver);
+    }
+  }
+#if DNS_LOCAL_HOSTLIST
+  dns_init_local();
+#endif
+}
+
+/**
+ * Initialize one of the DNS servers.
+ *
+ * @param numdns the index of the DNS server to set must be < DNS_MAX_SERVERS
+ * @param dnsserver IP address of the DNS server to set
+ */
+void
+dns_setserver(u8_t numdns, ip_addr_t *dnsserver)
+{
+  if ((numdns < DNS_MAX_SERVERS) && (dns_pcb != NULL) &&
+      (dnsserver != NULL) && !ip_addr_isany(dnsserver)) {
+    dns_servers[numdns] = (*dnsserver);
+  }
+}
+
+/**
+ * Obtain one of the currently configured DNS server.
+ *
+ * @param numdns the index of the DNS server
+ * @return IP address of the indexed DNS server or "ip_addr_any" if the DNS
+ *         server has not been configured.
+ */
+ip_addr_t
+dns_getserver(u8_t numdns)
+{
+  if (numdns < DNS_MAX_SERVERS) {
+    return dns_servers[numdns];
+  } else {
+    return *IP_ADDR_ANY;
+  }
+}
+
+/**
+ * The DNS resolver client timer - handle retries and timeouts and should
+ * be called every DNS_TMR_INTERVAL milliseconds (every second by default).
+ */
+void
+dns_tmr(void)
+{
+  if (dns_pcb != NULL) {
+    LWIP_DEBUGF(DNS_DEBUG, ("dns_tmr: dns_check_entries\n"));
+    dns_check_entries();
+  }
+}
+
+#if DNS_LOCAL_HOSTLIST
+static void
+dns_init_local()
+{
+#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC && defined(DNS_LOCAL_HOSTLIST_INIT)
+  int i;
+  struct local_hostlist_entry *entry;
+  /* Dynamic: copy entries from DNS_LOCAL_HOSTLIST_INIT to list */
+  struct local_hostlist_entry local_hostlist_init[] = DNS_LOCAL_HOSTLIST_INIT;
+  size_t namelen;
+  for (i = 0; i < sizeof(local_hostlist_init) / sizeof(struct local_hostlist_entry); i++) {
+    struct local_hostlist_entry *init_entry = &local_hostlist_init[i];
+    LWIP_ASSERT("invalid host name (NULL)", init_entry->name != NULL);
+    namelen = strlen(init_entry->name);
+    LWIP_ASSERT("namelen <= DNS_LOCAL_HOSTLIST_MAX_NAMELEN", namelen <= DNS_LOCAL_HOSTLIST_MAX_NAMELEN);
+    entry = (struct local_hostlist_entry *)memp_malloc(MEMP_LOCALHOSTLIST);
+    LWIP_ASSERT("mem-error in dns_init_local", entry != NULL);
+    if (entry != NULL) {
+      entry->name = (char*)entry + sizeof(struct local_hostlist_entry);
+      MEMCPY((char*)entry->name, init_entry->name, namelen);
+      ((char*)entry->name)[namelen] = 0;
+      entry->addr = init_entry->addr;
+      entry->next = local_hostlist_dynamic;
+      local_hostlist_dynamic = entry;
+    }
+  }
+#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC && defined(DNS_LOCAL_HOSTLIST_INIT) */
+}
+
+/**
+ * Scans the local host-list for a hostname.
+ *
+ * @param hostname Hostname to look for in the local host-list
+ * @return The first IP address for the hostname in the local host-list or
+ *         IPADDR_NONE if not found.
+ */
+static u32_t
+dns_lookup_local(const char *hostname)
+{
+#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC
+  struct local_hostlist_entry *entry = local_hostlist_dynamic;
+  while(entry != NULL) {
+    if(strcmp(entry->name, hostname) == 0) {
+      return ip4_addr_get_u32(&entry->addr);
+    }
+    entry = entry->next;
+  }
+#else /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+  int i;
+  for (i = 0; i < sizeof(local_hostlist_static) / sizeof(struct local_hostlist_entry); i++) {
+    if(strcmp(local_hostlist_static[i].name, hostname) == 0) {
+      return ip4_addr_get_u32(&local_hostlist_static[i].addr);
+    }
+  }
+#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+  return IPADDR_NONE;
+}
+
+#if DNS_LOCAL_HOSTLIST_IS_DYNAMIC
+/** Remove all entries from the local host-list for a specific hostname
+ * and/or IP addess
+ *
+ * @param hostname hostname for which entries shall be removed from the local
+ *                 host-list
+ * @param addr address for which entries shall be removed from the local host-list
+ * @return the number of removed entries
+ */
+int
+dns_local_removehost(const char *hostname, const ip_addr_t *addr)
+{
+  int removed = 0;
+  struct local_hostlist_entry *entry = local_hostlist_dynamic;
+  struct local_hostlist_entry *last_entry = NULL;
+  while (entry != NULL) {
+    if (((hostname == NULL) || !strcmp(entry->name, hostname)) &&
+        ((addr == NULL) || ip_addr_cmp(&entry->addr, addr))) {
+      struct local_hostlist_entry *free_entry;
+      if (last_entry != NULL) {
+        last_entry->next = entry->next;
+      } else {
+        local_hostlist_dynamic = entry->next;
+      }
+      free_entry = entry;
+      entry = entry->next;
+      memp_free(MEMP_LOCALHOSTLIST, free_entry);
+      removed++;
+    } else {
+      last_entry = entry;
+      entry = entry->next;
+    }
+  }
+  return removed;
+}
+
+/**
+ * Add a hostname/IP address pair to the local host-list.
+ * Duplicates are not checked.
+ *
+ * @param hostname hostname of the new entry
+ * @param addr IP address of the new entry
+ * @return ERR_OK if succeeded or ERR_MEM on memory error
+ */
+err_t
+dns_local_addhost(const char *hostname, const ip_addr_t *addr)
+{
+  struct local_hostlist_entry *entry;
+  size_t namelen;
+  LWIP_ASSERT("invalid host name (NULL)", hostname != NULL);
+  namelen = strlen(hostname);
+  LWIP_ASSERT("namelen <= DNS_LOCAL_HOSTLIST_MAX_NAMELEN", namelen <= DNS_LOCAL_HOSTLIST_MAX_NAMELEN);
+  entry = (struct local_hostlist_entry *)memp_malloc(MEMP_LOCALHOSTLIST);
+  if (entry == NULL) {
+    return ERR_MEM;
+  }
+  entry->name = (char*)entry + sizeof(struct local_hostlist_entry);
+  MEMCPY((char*)entry->name, hostname, namelen);
+  ((char*)entry->name)[namelen] = 0;
+  ip_addr_copy(entry->addr, *addr);
+  entry->next = local_hostlist_dynamic;
+  local_hostlist_dynamic = entry;
+  return ERR_OK;
+}
+#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC*/
+#endif /* DNS_LOCAL_HOSTLIST */
+
+/**
+ * Look up a hostname in the array of known hostnames.
+ *
+ * @note This function only looks in the internal array of known
+ * hostnames, it does not send out a query for the hostname if none
+ * was found. The function dns_enqueue() can be used to send a query
+ * for a hostname.
+ *
+ * @param name the hostname to look up
+ * @return the hostname's IP address, as u32_t (instead of ip_addr_t to
+ *         better check for failure: != IPADDR_NONE) or IPADDR_NONE if the hostname
+ *         was not found in the cached dns_table.
+ */
+static u32_t
+dns_lookup(const char *name)
+{
+  u8_t i;
+#if DNS_LOCAL_HOSTLIST || defined(DNS_LOOKUP_LOCAL_EXTERN)
+  u32_t addr;
+#endif /* DNS_LOCAL_HOSTLIST || defined(DNS_LOOKUP_LOCAL_EXTERN) */
+#if DNS_LOCAL_HOSTLIST
+  if ((addr = dns_lookup_local(name)) != IPADDR_NONE) {
+    return addr;
+  }
+#endif /* DNS_LOCAL_HOSTLIST */
+#ifdef DNS_LOOKUP_LOCAL_EXTERN
+  if((addr = DNS_LOOKUP_LOCAL_EXTERN(name)) != IPADDR_NONE) {
+    return addr;
+  }
+#endif /* DNS_LOOKUP_LOCAL_EXTERN */
+
+  /* Walk through name list, return entry if found. If not, return NULL. */
+  for (i = 0; i < DNS_TABLE_SIZE; ++i) {
+    if ((dns_table[i].state == DNS_STATE_DONE) &&
+        (strcmp(name, dns_table[i].name) == 0)) {
+      LWIP_DEBUGF(DNS_DEBUG, ("dns_lookup: \"%s\": found = ", name));
+      ip_addr_debug_print(DNS_DEBUG, &(dns_table[i].ipaddr));
+      LWIP_DEBUGF(DNS_DEBUG, ("\n"));
+      return ip4_addr_get_u32(&dns_table[i].ipaddr);
+    }
+  }
+
+  return IPADDR_NONE;
+}
+
+#if DNS_DOES_NAME_CHECK
+/**
+ * Compare the "dotted" name "query" with the encoded name "response"
+ * to make sure an answer from the DNS server matches the current dns_table
+ * entry (otherwise, answers might arrive late for hostname not on the list
+ * any more).
+ *
+ * @param query hostname (not encoded) from the dns_table
+ * @param response encoded hostname in the DNS response
+ * @return 0: names equal; 1: names differ
+ */
+static u8_t
+dns_compare_name(unsigned char *query, unsigned char *response)
+{
+  unsigned char n;
+
+  do {
+    n = *response++;
+    /** @see RFC 1035 - 4.1.4. Message compression */
+    if ((n & 0xc0) == 0xc0) {
+      /* Compressed name */
+      break;
+    } else {
+      /* Not compressed name */
+      while (n > 0) {
+        if ((*query) != (*response)) {
+          return 1;
+        }
+        ++response;
+        ++query;
+        --n;
+      };
+      ++query;
+    }
+  } while (*response != 0);
+
+  return 0;
+}
+#endif /* DNS_DOES_NAME_CHECK */
+
+/**
+ * Walk through a compact encoded DNS name and return the end of the name.
+ *
+ * @param query encoded DNS name in the DNS server response
+ * @return end of the name
+ */
+static unsigned char *
+dns_parse_name(unsigned char *query)
+{
+  unsigned char n;
+
+  do {
+    n = *query++;
+    /** @see RFC 1035 - 4.1.4. Message compression */
+    if ((n & 0xc0) == 0xc0) {
+      /* Compressed name */
+      break;
+    } else {
+      /* Not compressed name */
+      while (n > 0) {
+        ++query;
+        --n;
+      };
+    }
+  } while (*query != 0);
+
+  return query + 1;
+}
+
+/**
+ * Send a DNS query packet.
+ *
+ * @param numdns index of the DNS server in the dns_servers table
+ * @param name hostname to query
+ * @param id index of the hostname in dns_table, used as transaction ID in the
+ *        DNS query packet
+ * @return ERR_OK if packet is sent; an err_t indicating the problem otherwise
+ */
+static err_t
+dns_send(u8_t numdns, const char* name, u8_t id)
+{
+  err_t err;
+  struct dns_hdr *hdr;
+  struct dns_query qry;
+  struct pbuf *p;
+  char *query, *nptr;
+  const char *pHostname;
+  u8_t n;
+
+  LWIP_DEBUGF(DNS_DEBUG, ("dns_send: dns_servers[%"U16_F"] \"%s\": request\n",
+              (u16_t)(numdns), name));
+  LWIP_ASSERT("dns server out of array", numdns < DNS_MAX_SERVERS);
+  LWIP_ASSERT("dns server has no IP address set", !ip_addr_isany(&dns_servers[numdns]));
+
+  /* if here, we have either a new query or a retry on a previous query to process */
+  p = pbuf_alloc(PBUF_TRANSPORT, SIZEOF_DNS_HDR + DNS_MAX_NAME_LENGTH +
+                 SIZEOF_DNS_QUERY, PBUF_RAM);
+  if (p != NULL) {
+    LWIP_ASSERT("pbuf must be in one piece", p->next == NULL);
+    /* fill dns header */
+    hdr = (struct dns_hdr*)p->payload;
+    memset(hdr, 0, SIZEOF_DNS_HDR);
+    hdr->id = htons(id);
+    hdr->flags1 = DNS_FLAG1_RD;
+    hdr->numquestions = PP_HTONS(1);
+    query = (char*)hdr + SIZEOF_DNS_HDR;
+    pHostname = name;
+    --pHostname;
+
+    /* convert hostname into suitable query format. */
+    do {
+      ++pHostname;
+      nptr = query;
+      ++query;
+      for(n = 0; *pHostname != '.' && *pHostname != 0; ++pHostname) {
+        *query = *pHostname;
+        ++query;
+        ++n;
+      }
+      *nptr = n;
+    } while(*pHostname != 0);
+    *query++='\0';
+
+    /* fill dns query */
+    qry.type = PP_HTONS(DNS_RRTYPE_A);
+    qry.cls = PP_HTONS(DNS_RRCLASS_IN);
+    SMEMCPY(query, &qry, SIZEOF_DNS_QUERY);
+
+    /* resize pbuf to the exact dns query */
+    pbuf_realloc(p, (u16_t)((query + SIZEOF_DNS_QUERY) - ((char*)(p->payload))));
+
+    /* connect to the server for faster receiving */
+    udp_connect(dns_pcb, &dns_servers[numdns], DNS_SERVER_PORT);
+    /* send dns packet */
+    err = udp_sendto(dns_pcb, p, &dns_servers[numdns], DNS_SERVER_PORT);
+
+    /* free pbuf */
+    pbuf_free(p);
+  } else {
+    err = ERR_MEM;
+  }
+
+  return err;
+}
+
+/**
+ * dns_check_entry() - see if pEntry has not yet been queried and, if so, sends out a query.
+ * Check an entry in the dns_table:
+ * - send out query for new entries
+ * - retry old pending entries on timeout (also with different servers)
+ * - remove completed entries from the table if their TTL has expired
+ *
+ * @param i index of the dns_table entry to check
+ */
+static void
+dns_check_entry(u8_t i)
+{
+  err_t err;
+  struct dns_table_entry *pEntry = &dns_table[i];
+
+  LWIP_ASSERT("array index out of bounds", i < DNS_TABLE_SIZE);
+
+  switch(pEntry->state) {
+
+    case DNS_STATE_NEW: {
+      /* initialize new entry */
+      pEntry->state   = DNS_STATE_ASKING;
+      pEntry->numdns  = 0;
+      pEntry->tmr     = 1;
+      pEntry->retries = 0;
+      
+      /* send DNS packet for this entry */
+      err = dns_send(pEntry->numdns, pEntry->name, i);
+      if (err != ERR_OK) {
+        LWIP_DEBUGF(DNS_DEBUG | LWIP_DBG_LEVEL_WARNING,
+                    ("dns_send returned error: %s\n", lwip_strerr(err)));
+      }
+      break;
+    }
+
+    case DNS_STATE_ASKING: {
+      if (--pEntry->tmr == 0) {
+        if (++pEntry->retries == DNS_MAX_RETRIES) {
+          if ((pEntry->numdns+1<DNS_MAX_SERVERS) && !ip_addr_isany(&dns_servers[pEntry->numdns+1])) {
+            /* change of server */
+            pEntry->numdns++;
+            pEntry->tmr     = 1;
+            pEntry->retries = 0;
+            break;
+          } else {
+            LWIP_DEBUGF(DNS_DEBUG, ("dns_check_entry: \"%s\": timeout\n", pEntry->name));
+            /* call specified callback function if provided */
+            if (pEntry->found)
+              (*pEntry->found)(pEntry->name, NULL, pEntry->arg);
+            /* flush this entry */
+            pEntry->state   = DNS_STATE_UNUSED;
+            pEntry->found   = NULL;
+            break;
+          }
+        }
+
+        /* wait longer for the next retry */
+        pEntry->tmr = pEntry->retries;
+
+        /* send DNS packet for this entry */
+        err = dns_send(pEntry->numdns, pEntry->name, i);
+        if (err != ERR_OK) {
+          LWIP_DEBUGF(DNS_DEBUG | LWIP_DBG_LEVEL_WARNING,
+                      ("dns_send returned error: %s\n", lwip_strerr(err)));
+        }
+      }
+      break;
+    }
+
+    case DNS_STATE_DONE: {
+      /* if the time to live is nul */
+      if (--pEntry->ttl == 0) {
+        LWIP_DEBUGF(DNS_DEBUG, ("dns_check_entry: \"%s\": flush\n", pEntry->name));
+        /* flush this entry */
+        pEntry->state = DNS_STATE_UNUSED;
+        pEntry->found = NULL;
+      }
+      break;
+    }
+    case DNS_STATE_UNUSED:
+      /* nothing to do */
+      break;
+    default:
+      LWIP_ASSERT("unknown dns_table entry state:", 0);
+      break;
+  }
+}
+
+/**
+ * Call dns_check_entry for each entry in dns_table - check all entries.
+ */
+static void
+dns_check_entries(void)
+{
+  u8_t i;
+
+  for (i = 0; i < DNS_TABLE_SIZE; ++i) {
+    dns_check_entry(i);
+  }
+}
+
+/**
+ * Receive input function for DNS response packets arriving for the dns UDP pcb.
+ *
+ * @params see udp.h
+ */
+static void
+dns_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *addr, u16_t port)
+{
+  u16_t i;
+  char *pHostname;
+  struct dns_hdr *hdr;
+  struct dns_answer ans;
+  struct dns_table_entry *pEntry;
+  u16_t nquestions, nanswers;
+
+  LWIP_UNUSED_ARG(arg);
+  LWIP_UNUSED_ARG(pcb);
+  LWIP_UNUSED_ARG(addr);
+  LWIP_UNUSED_ARG(port);
+
+  /* is the dns message too big ? */
+  if (p->tot_len > DNS_MSG_SIZE) {
+    LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: pbuf too big\n"));
+    /* free pbuf and return */
+    goto memerr;
+  }
+
+  /* is the dns message big enough ? */
+  if (p->tot_len < (SIZEOF_DNS_HDR + SIZEOF_DNS_QUERY + SIZEOF_DNS_ANSWER)) {
+    LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: pbuf too small\n"));
+    /* free pbuf and return */
+    goto memerr;
+  }
+
+  /* copy dns payload inside static buffer for processing */ 
+  if (pbuf_copy_partial(p, dns_payload, p->tot_len, 0) == p->tot_len) {
+    /* The ID in the DNS header should be our entry into the name table. */
+    hdr = (struct dns_hdr*)dns_payload;
+    i = htons(hdr->id);
+    if (i < DNS_TABLE_SIZE) {
+      pEntry = &dns_table[i];
+      if(pEntry->state == DNS_STATE_ASKING) {
+        /* This entry is now completed. */
+        pEntry->state = DNS_STATE_DONE;
+        pEntry->err   = hdr->flags2 & DNS_FLAG2_ERR_MASK;
+
+        /* We only care about the question(s) and the answers. The authrr
+           and the extrarr are simply discarded. */
+        nquestions = htons(hdr->numquestions);
+        nanswers   = htons(hdr->numanswers);
+
+        /* Check for error. If so, call callback to inform. */
+        if (((hdr->flags1 & DNS_FLAG1_RESPONSE) == 0) || (pEntry->err != 0) || (nquestions != 1)) {
+          LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": error in flags\n", pEntry->name));
+          /* call callback to indicate error, clean up memory and return */
+          goto responseerr;
+        }
+
+#if DNS_DOES_NAME_CHECK
+        /* Check if the name in the "question" part match with the name in the entry. */
+        if (dns_compare_name((unsigned char *)(pEntry->name), (unsigned char *)dns_payload + SIZEOF_DNS_HDR) != 0) {
+          LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": response not match to query\n", pEntry->name));
+          /* call callback to indicate error, clean up memory and return */
+          goto responseerr;
+        }
+#endif /* DNS_DOES_NAME_CHECK */
+
+        /* Skip the name in the "question" part */
+        pHostname = (char *) dns_parse_name((unsigned char *)dns_payload + SIZEOF_DNS_HDR) + SIZEOF_DNS_QUERY;
+
+        while (nanswers > 0) {
+          /* skip answer resource record's host name */
+          pHostname = (char *) dns_parse_name((unsigned char *)pHostname);
+
+          /* Check for IP address type and Internet class. Others are discarded. */
+          SMEMCPY(&ans, pHostname, SIZEOF_DNS_ANSWER);
+          if((ans.type == PP_HTONS(DNS_RRTYPE_A)) && (ans.cls == PP_HTONS(DNS_RRCLASS_IN)) &&
+             (ans.len == PP_HTONS(sizeof(ip_addr_t))) ) {
+            /* read the answer resource record's TTL, and maximize it if needed */
+            pEntry->ttl = ntohl(ans.ttl);
+            if (pEntry->ttl > DNS_MAX_TTL) {
+              pEntry->ttl = DNS_MAX_TTL;
+            }
+            /* read the IP address after answer resource record's header */
+            SMEMCPY(&(pEntry->ipaddr), (pHostname+SIZEOF_DNS_ANSWER), sizeof(ip_addr_t));
+            LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": response = ", pEntry->name));
+            ip_addr_debug_print(DNS_DEBUG, (&(pEntry->ipaddr)));
+            LWIP_DEBUGF(DNS_DEBUG, ("\n"));
+            /* call specified callback function if provided */
+            if (pEntry->found) {
+              (*pEntry->found)(pEntry->name, &pEntry->ipaddr, pEntry->arg);
+            }
+            /* deallocate memory and return */
+            goto memerr;
+          } else {
+            pHostname = pHostname + SIZEOF_DNS_ANSWER + htons(ans.len);
+          }
+          --nanswers;
+        }
+        LWIP_DEBUGF(DNS_DEBUG, ("dns_recv: \"%s\": error in response\n", pEntry->name));
+        /* call callback to indicate error, clean up memory and return */
+        goto responseerr;
+      }
+    }
+  }
+
+  /* deallocate memory and return */
+  goto memerr;
+
+responseerr:
+  /* ERROR: call specified callback function with NULL as name to indicate an error */
+  if (pEntry->found) {
+    (*pEntry->found)(pEntry->name, NULL, pEntry->arg);
+  }
+  /* flush this entry */
+  pEntry->state = DNS_STATE_UNUSED;
+  pEntry->found = NULL;
+
+memerr:
+  /* free pbuf */
+  pbuf_free(p);
+  return;
+}
+
+/**
+ * Queues a new hostname to resolve and sends out a DNS query for that hostname
+ *
+ * @param name the hostname that is to be queried
+ * @param found a callback founction to be called on success, failure or timeout
+ * @param callback_arg argument to pass to the callback function
+ * @return @return a err_t return code.
+ */
+static err_t
+dns_enqueue(const char *name, dns_found_callback found, void *callback_arg)
+{
+  u8_t i;
+  u8_t lseq, lseqi;
+  struct dns_table_entry *pEntry = NULL;
+  size_t namelen;
+
+  /* search an unused entry, or the oldest one */
+  lseq = lseqi = 0;
+  for (i = 0; i < DNS_TABLE_SIZE; ++i) {
+    pEntry = &dns_table[i];
+    /* is it an unused entry ? */
+    if (pEntry->state == DNS_STATE_UNUSED)
+      break;
+
+    /* check if this is the oldest completed entry */
+    if (pEntry->state == DNS_STATE_DONE) {
+      if ((dns_seqno - pEntry->seqno) > lseq) {
+        lseq = dns_seqno - pEntry->seqno;
+        lseqi = i;
+      }
+    }
+  }
+
+  /* if we don't have found an unused entry, use the oldest completed one */
+  if (i == DNS_TABLE_SIZE) {
+    if ((lseqi >= DNS_TABLE_SIZE) || (dns_table[lseqi].state != DNS_STATE_DONE)) {
+      /* no entry can't be used now, table is full */
+      LWIP_DEBUGF(DNS_DEBUG, ("dns_enqueue: \"%s\": DNS entries table is full\n", name));
+      return ERR_MEM;
+    } else {
+      /* use the oldest completed one */
+      i = lseqi;
+      pEntry = &dns_table[i];
+    }
+  }
+
+  /* use this entry */
+  LWIP_DEBUGF(DNS_DEBUG, ("dns_enqueue: \"%s\": use DNS entry %"U16_F"\n", name, (u16_t)(i)));
+
+  /* fill the entry */
+  pEntry->state = DNS_STATE_NEW;
+  pEntry->seqno = dns_seqno++;
+  pEntry->found = found;
+  pEntry->arg   = callback_arg;
+  namelen = LWIP_MIN(strlen(name), DNS_MAX_NAME_LENGTH-1);
+  MEMCPY(pEntry->name, name, namelen);
+  pEntry->name[namelen] = 0;
+
+  /* force to send query without waiting timer */
+  dns_check_entry(i);
+
+  /* dns query is enqueued */
+  return ERR_INPROGRESS;
+}
+
+/**
+ * Resolve a hostname (string) into an IP address.
+ * NON-BLOCKING callback version for use with raw API!!!
+ *
+ * Returns immediately with one of err_t return codes:
+ * - ERR_OK if hostname is a valid IP address string or the host
+ *   name is already in the local names table.
+ * - ERR_INPROGRESS enqueue a request to be sent to the DNS server
+ *   for resolution if no errors are present.
+ * - ERR_ARG: dns client not initialized or invalid hostname
+ *
+ * @param hostname the hostname that is to be queried
+ * @param addr pointer to a ip_addr_t where to store the address if it is already
+ *             cached in the dns_table (only valid if ERR_OK is returned!)
+ * @param found a callback function to be called on success, failure or timeout (only if
+ *              ERR_INPROGRESS is returned!)
+ * @param callback_arg argument to pass to the callback function
+ * @return a err_t return code.
+ */
+err_t
+dns_gethostbyname(const char *hostname, ip_addr_t *addr, dns_found_callback found,
+                  void *callback_arg)
+{
+  u32_t ipaddr;
+  /* not initialized or no valid server yet, or invalid addr pointer
+   * or invalid hostname or invalid hostname length */
+  if ((dns_pcb == NULL) || (addr == NULL) ||
+      (!hostname) || (!hostname[0]) ||
+      (strlen(hostname) >= DNS_MAX_NAME_LENGTH)) {
+    return ERR_ARG;
+  }
+
+#if LWIP_HAVE_LOOPIF
+  if (strcmp(hostname, "localhost")==0) {
+    ip_addr_set_loopback(addr);
+    return ERR_OK;
+  }
+#endif /* LWIP_HAVE_LOOPIF */
+
+  /* host name already in octet notation? set ip addr and return ERR_OK */
+  ipaddr = ipaddr_addr(hostname);
+  if (ipaddr == IPADDR_NONE) {
+    /* already have this address cached? */
+    ipaddr = dns_lookup(hostname);
+  }
+  if (ipaddr != IPADDR_NONE) {
+    ip4_addr_set_u32(addr, ipaddr);
+    return ERR_OK;
+  }
+
+  /* queue query with specified callback */
+  return dns_enqueue(hostname, found, callback_arg);
+}
+
+#endif /* LWIP_DNS */

src/lwip-1.4.1/src/core/init.c

@@ -0,0 +1,332 @@
+/**
+ * @file
+ * Modules initialization
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/init.h"
+#include "lwip/stats.h"
+#include "lwip/sys.h"
+#include "lwip/mem.h"
+#include "lwip/memp.h"
+#include "lwip/pbuf.h"
+#include "lwip/netif.h"
+#include "lwip/sockets.h"
+#include "lwip/ip.h"
+#include "lwip/raw.h"
+#include "lwip/udp.h"
+#include "lwip/tcp_impl.h"
+#include "lwip/snmp_msg.h"
+#include "lwip/autoip.h"
+#include "lwip/igmp.h"
+#include "lwip/dns.h"
+#include "lwip/timers.h"
+#include "netif/etharp.h"
+#include "lwip/api.h"
+
+/* Compile-time sanity checks for configuration errors.
+ * These can be done independently of LWIP_DEBUG, without penalty.
+ */
+#ifndef BYTE_ORDER
+  #error "BYTE_ORDER is not defined, you have to define it in your cc.h"
+#endif
+#if (!IP_SOF_BROADCAST && IP_SOF_BROADCAST_RECV)
+  #error "If you want to use broadcast filter per pcb on recv operations, you have to define IP_SOF_BROADCAST=1 in your lwipopts.h"
+#endif
+#if (!LWIP_UDP && LWIP_UDPLITE)
+  #error "If you want to use UDP Lite, you have to define LWIP_UDP=1 in your lwipopts.h"
+#endif
+#if (!LWIP_UDP && LWIP_SNMP)
+  #error "If you want to use SNMP, you have to define LWIP_UDP=1 in your lwipopts.h"
+#endif
+#if (!LWIP_UDP && LWIP_DHCP)
+  #error "If you want to use DHCP, you have to define LWIP_UDP=1 in your lwipopts.h"
+#endif
+#if (!LWIP_UDP && LWIP_IGMP)
+  #error "If you want to use IGMP, you have to define LWIP_UDP=1 in your lwipopts.h"
+#endif
+#if (!LWIP_UDP && LWIP_SNMP)
+  #error "If you want to use SNMP, you have to define LWIP_UDP=1 in your lwipopts.h"
+#endif
+#if (!LWIP_UDP && LWIP_DNS)
+  #error "If you want to use DNS, you have to define LWIP_UDP=1 in your lwipopts.h"
+#endif
+#if !MEMP_MEM_MALLOC /* MEMP_NUM_* checks are disabled when not using the pool allocator */
+#if (LWIP_ARP && ARP_QUEUEING && (MEMP_NUM_ARP_QUEUE<=0))
+  #error "If you want to use ARP Queueing, you have to define MEMP_NUM_ARP_QUEUE>=1 in your lwipopts.h"
+#endif
+#if (LWIP_RAW && (MEMP_NUM_RAW_PCB<=0))
+  #error "If you want to use RAW, you have to define MEMP_NUM_RAW_PCB>=1 in your lwipopts.h"
+#endif
+#if (LWIP_UDP && (MEMP_NUM_UDP_PCB<=0))
+  #error "If you want to use UDP, you have to define MEMP_NUM_UDP_PCB>=1 in your lwipopts.h"
+#endif
+#if (LWIP_TCP && (MEMP_NUM_TCP_PCB<=0))
+  #error "If you want to use TCP, you have to define MEMP_NUM_TCP_PCB>=1 in your lwipopts.h"
+#endif
+#if (LWIP_IGMP && (MEMP_NUM_IGMP_GROUP<=1))
+  #error "If you want to use IGMP, you have to define MEMP_NUM_IGMP_GROUP>1 in your lwipopts.h"
+#endif
+#if ((LWIP_NETCONN || LWIP_SOCKET) && (MEMP_NUM_TCPIP_MSG_API<=0))
+  #error "If you want to use Sequential API, you have to define MEMP_NUM_TCPIP_MSG_API>=1 in your lwipopts.h"
+#endif
+/* There must be sufficient timeouts, taking into account requirements of the subsystems. */
+#if LWIP_TIMERS && (MEMP_NUM_SYS_TIMEOUT < (LWIP_TCP + IP_REASSEMBLY + LWIP_ARP + (2*LWIP_DHCP) + LWIP_AUTOIP + LWIP_IGMP + LWIP_DNS + PPP_SUPPORT))
+  #error "MEMP_NUM_SYS_TIMEOUT is too low to accomodate all required timeouts"
+#endif
+#if (IP_REASSEMBLY && (MEMP_NUM_REASSDATA > IP_REASS_MAX_PBUFS))
+  #error "MEMP_NUM_REASSDATA > IP_REASS_MAX_PBUFS doesn't make sense since each struct ip_reassdata must hold 2 pbufs at least!"
+#endif
+#endif /* !MEMP_MEM_MALLOC */
+#if (LWIP_TCP && (TCP_WND > 0xffff))
+  #error "If you want to use TCP, TCP_WND must fit in an u16_t, so, you have to reduce it in your lwipopts.h"
+#endif
+#if (LWIP_TCP && (TCP_SND_QUEUELEN > 0xffff))
+  #error "If you want to use TCP, TCP_SND_QUEUELEN must fit in an u16_t, so, you have to reduce it in your lwipopts.h"
+#endif
+#if (LWIP_TCP && (TCP_SND_QUEUELEN < 2))
+  #error "TCP_SND_QUEUELEN must be at least 2 for no-copy TCP writes to work"
+#endif
+#if (LWIP_TCP && ((TCP_MAXRTX > 12) || (TCP_SYNMAXRTX > 12)))
+  #error "If you want to use TCP, TCP_MAXRTX and TCP_SYNMAXRTX must less or equal to 12 (due to tcp_backoff table), so, you have to reduce them in your lwipopts.h"
+#endif
+#if (LWIP_TCP && TCP_LISTEN_BACKLOG && (TCP_DEFAULT_LISTEN_BACKLOG < 0) || (TCP_DEFAULT_LISTEN_BACKLOG > 0xff))
+  #error "If you want to use TCP backlog, TCP_DEFAULT_LISTEN_BACKLOG must fit into an u8_t"
+#endif
+#if (LWIP_NETIF_API && (NO_SYS==1))
+  #error "If you want to use NETIF API, you have to define NO_SYS=0 in your lwipopts.h"
+#endif
+#if ((LWIP_SOCKET || LWIP_NETCONN) && (NO_SYS==1))
+  #error "If you want to use Sequential API, you have to define NO_SYS=0 in your lwipopts.h"
+#endif
+#if (!LWIP_NETCONN && LWIP_SOCKET)
+  #error "If you want to use Socket API, you have to define LWIP_NETCONN=1 in your lwipopts.h"
+#endif
+#if (((!LWIP_DHCP) || (!LWIP_AUTOIP)) && LWIP_DHCP_AUTOIP_COOP)
+  #error "If you want to use DHCP/AUTOIP cooperation mode, you have to define LWIP_DHCP=1 and LWIP_AUTOIP=1 in your lwipopts.h"
+#endif
+#if (((!LWIP_DHCP) || (!LWIP_ARP)) && DHCP_DOES_ARP_CHECK)
+  #error "If you want to use DHCP ARP checking, you have to define LWIP_DHCP=1 and LWIP_ARP=1 in your lwipopts.h"
+#endif
+#if (!LWIP_ARP && LWIP_AUTOIP)
+  #error "If you want to use AUTOIP, you have to define LWIP_ARP=1 in your lwipopts.h"
+#endif
+#if (LWIP_SNMP && (SNMP_CONCURRENT_REQUESTS<=0))
+  #error "If you want to use SNMP, you have to define SNMP_CONCURRENT_REQUESTS>=1 in your lwipopts.h"
+#endif
+#if (LWIP_SNMP && (SNMP_TRAP_DESTINATIONS<=0))
+  #error "If you want to use SNMP, you have to define SNMP_TRAP_DESTINATIONS>=1 in your lwipopts.h"
+#endif
+#if (LWIP_TCP && ((LWIP_EVENT_API && LWIP_CALLBACK_API) || (!LWIP_EVENT_API && !LWIP_CALLBACK_API)))
+  #error "One and exactly one of LWIP_EVENT_API and LWIP_CALLBACK_API has to be enabled in your lwipopts.h"
+#endif
+#if (MEM_LIBC_MALLOC && MEM_USE_POOLS)
+  #error "MEM_LIBC_MALLOC and MEM_USE_POOLS may not both be simultaneously enabled in your lwipopts.h"
+#endif
+#if (MEM_USE_POOLS && !MEMP_USE_CUSTOM_POOLS)
+  #error "MEM_USE_POOLS requires custom pools (MEMP_USE_CUSTOM_POOLS) to be enabled in your lwipopts.h"
+#endif
+#if (PBUF_POOL_BUFSIZE <= MEM_ALIGNMENT)
+  #error "PBUF_POOL_BUFSIZE must be greater than MEM_ALIGNMENT or the offset may take the full first pbuf"
+#endif
+#if (DNS_LOCAL_HOSTLIST && !DNS_LOCAL_HOSTLIST_IS_DYNAMIC && !(defined(DNS_LOCAL_HOSTLIST_INIT)))
+  #error "you have to define define DNS_LOCAL_HOSTLIST_INIT {{'host1', 0x123}, {'host2', 0x234}} to initialize DNS_LOCAL_HOSTLIST"
+#endif
+#if PPP_SUPPORT && !PPPOS_SUPPORT & !PPPOE_SUPPORT
+  #error "PPP_SUPPORT needs either PPPOS_SUPPORT or PPPOE_SUPPORT turned on"
+#endif
+#if !LWIP_ETHERNET && (LWIP_ARP || PPPOE_SUPPORT)
+  #error "LWIP_ETHERNET needs to be turned on for LWIP_ARP or PPPOE_SUPPORT"
+#endif
+#if LWIP_IGMP && !defined(LWIP_RAND)
+  #error "When using IGMP, LWIP_RAND() needs to be defined to a random-function returning an u32_t random value"
+#endif
+#if LWIP_TCPIP_CORE_LOCKING_INPUT && !LWIP_TCPIP_CORE_LOCKING
+  #error "When using LWIP_TCPIP_CORE_LOCKING_INPUT, LWIP_TCPIP_CORE_LOCKING must be enabled, too"
+#endif
+#if LWIP_TCP && LWIP_NETIF_TX_SINGLE_PBUF && !TCP_OVERSIZE
+  #error "LWIP_NETIF_TX_SINGLE_PBUF needs TCP_OVERSIZE enabled to create single-pbuf TCP packets"
+#endif
+#if IP_FRAG && IP_FRAG_USES_STATIC_BUF && LWIP_NETIF_TX_SINGLE_PBUF
+  #error "LWIP_NETIF_TX_SINGLE_PBUF does not work with IP_FRAG_USES_STATIC_BUF==1 as that creates pbuf queues"
+#endif
+#if LWIP_NETCONN && LWIP_TCP
+#if NETCONN_COPY != TCP_WRITE_FLAG_COPY
+  #error "NETCONN_COPY != TCP_WRITE_FLAG_COPY"
+#endif
+#if NETCONN_MORE != TCP_WRITE_FLAG_MORE
+  #error "NETCONN_MORE != TCP_WRITE_FLAG_MORE"
+#endif
+#endif /* LWIP_NETCONN && LWIP_TCP */ 
+#if LWIP_SOCKET
+/* Check that the SO_* socket options and SOF_* lwIP-internal flags match */
+#if SO_ACCEPTCONN != SOF_ACCEPTCONN
+  #error "SO_ACCEPTCONN != SOF_ACCEPTCONN"
+#endif
+#if SO_REUSEADDR != SOF_REUSEADDR
+  #error "WARNING: SO_REUSEADDR != SOF_REUSEADDR"
+#endif
+#if SO_KEEPALIVE != SOF_KEEPALIVE
+  #error "WARNING: SO_KEEPALIVE != SOF_KEEPALIVE"
+#endif
+#if SO_BROADCAST != SOF_BROADCAST
+  #error "WARNING: SO_BROADCAST != SOF_BROADCAST"
+#endif
+#if SO_LINGER != SOF_LINGER
+  #error "WARNING: SO_LINGER != SOF_LINGER"
+#endif
+#endif /* LWIP_SOCKET */
+
+
+/* Compile-time checks for deprecated options.
+ */
+#ifdef MEMP_NUM_TCPIP_MSG
+  #error "MEMP_NUM_TCPIP_MSG option is deprecated. Remove it from your lwipopts.h."
+#endif
+#ifdef MEMP_NUM_API_MSG
+  #error "MEMP_NUM_API_MSG option is deprecated. Remove it from your lwipopts.h."
+#endif
+#ifdef TCP_REXMIT_DEBUG
+  #error "TCP_REXMIT_DEBUG option is deprecated. Remove it from your lwipopts.h."
+#endif
+#ifdef RAW_STATS
+  #error "RAW_STATS option is deprecated. Remove it from your lwipopts.h."
+#endif
+#ifdef ETHARP_QUEUE_FIRST
+  #error "ETHARP_QUEUE_FIRST option is deprecated. Remove it from your lwipopts.h."
+#endif
+#ifdef ETHARP_ALWAYS_INSERT
+  #error "ETHARP_ALWAYS_INSERT option is deprecated. Remove it from your lwipopts.h."
+#endif
+
+#ifndef LWIP_DISABLE_TCP_SANITY_CHECKS
+#define LWIP_DISABLE_TCP_SANITY_CHECKS  0
+#endif
+#ifndef LWIP_DISABLE_MEMP_SANITY_CHECKS
+#define LWIP_DISABLE_MEMP_SANITY_CHECKS 0
+#endif
+
+/* MEMP sanity checks */
+#if !LWIP_DISABLE_MEMP_SANITY_CHECKS
+#if LWIP_NETCONN
+#if MEMP_MEM_MALLOC
+#if !MEMP_NUM_NETCONN && LWIP_SOCKET
+#error "lwip_sanity_check: WARNING: MEMP_NUM_NETCONN cannot be 0 when using sockets!"
+#endif
+#else /* MEMP_MEM_MALLOC */
+#if MEMP_NUM_NETCONN > (MEMP_NUM_TCP_PCB+MEMP_NUM_TCP_PCB_LISTEN+MEMP_NUM_UDP_PCB+MEMP_NUM_RAW_PCB)
+#error "lwip_sanity_check: WARNING: MEMP_NUM_NETCONN should be less than the sum of MEMP_NUM_{TCP,RAW,UDP}_PCB+MEMP_NUM_TCP_PCB_LISTEN. If you know what you are doing, define LWIP_DISABLE_MEMP_SANITY_CHECKS to 1 to disable this error."
+#endif
+#endif /* MEMP_MEM_MALLOC */
+#endif /* LWIP_NETCONN */
+#endif /* !LWIP_DISABLE_MEMP_SANITY_CHECKS */
+
+/* TCP sanity checks */
+#if !LWIP_DISABLE_TCP_SANITY_CHECKS
+#if LWIP_TCP
+#if !MEMP_MEM_MALLOC && (MEMP_NUM_TCP_SEG < TCP_SND_QUEUELEN)
+  #error "lwip_sanity_check: WARNING: MEMP_NUM_TCP_SEG should be at least as big as TCP_SND_QUEUELEN. If you know what you are doing, define LWIP_DISABLE_TCP_SANITY_CHECKS to 1 to disable this error."
+#endif
+#if TCP_SND_BUF < (2 * TCP_MSS)
+  #error "lwip_sanity_check: WARNING: TCP_SND_BUF must be at least as much as (2 * TCP_MSS) for things to work smoothly. If you know what you are doing, define LWIP_DISABLE_TCP_SANITY_CHECKS to 1 to disable this error."
+#endif
+#if TCP_SND_QUEUELEN < (2 * (TCP_SND_BUF / TCP_MSS))
+  #error "lwip_sanity_check: WARNING: TCP_SND_QUEUELEN must be at least as much as (2 * TCP_SND_BUF/TCP_MSS) for things to work. If you know what you are doing, define LWIP_DISABLE_TCP_SANITY_CHECKS to 1 to disable this error."
+#endif
+#if TCP_SNDLOWAT >= TCP_SND_BUF
+  #error "lwip_sanity_check: WARNING: TCP_SNDLOWAT must be less than TCP_SND_BUF. If you know what you are doing, define LWIP_DISABLE_TCP_SANITY_CHECKS to 1 to disable this error."
+#endif
+#if TCP_SNDQUEUELOWAT >= TCP_SND_QUEUELEN
+  #error "lwip_sanity_check: WARNING: TCP_SNDQUEUELOWAT must be less than TCP_SND_QUEUELEN. If you know what you are doing, define LWIP_DISABLE_TCP_SANITY_CHECKS to 1 to disable this error."
+#endif
+#if !MEMP_MEM_MALLOC && (TCP_WND > (PBUF_POOL_SIZE * (PBUF_POOL_BUFSIZE - (PBUF_LINK_HLEN + PBUF_IP_HLEN + PBUF_TRANSPORT_HLEN))))
+  #error "lwip_sanity_check: WARNING: TCP_WND is larger than space provided by PBUF_POOL_SIZE * (PBUF_POOL_BUFSIZE - protocol headers). If you know what you are doing, define LWIP_DISABLE_TCP_SANITY_CHECKS to 1 to disable this error."
+#endif
+#if TCP_WND < TCP_MSS
+  #error "lwip_sanity_check: WARNING: TCP_WND is smaller than MSS. If you know what you are doing, define LWIP_DISABLE_TCP_SANITY_CHECKS to 1 to disable this error."
+#endif
+#endif /* LWIP_TCP */
+#endif /* !LWIP_DISABLE_TCP_SANITY_CHECKS */
+
+/**
+ * Perform Sanity check of user-configurable values, and initialize all modules.
+ */
+void
+lwip_init(void)
+{
+  /* Modules initialization */
+  stats_init();
+#if !NO_SYS
+  sys_init();
+#endif /* !NO_SYS */
+  mem_init();
+  memp_init();
+  pbuf_init();
+  netif_init();
+#if LWIP_SOCKET
+  lwip_socket_init();
+#endif /* LWIP_SOCKET */
+  ip_init();
+#if LWIP_ARP
+  etharp_init();
+#endif /* LWIP_ARP */
+#if LWIP_RAW
+  raw_init();
+#endif /* LWIP_RAW */
+#if LWIP_UDP
+  udp_init();
+#endif /* LWIP_UDP */
+#if LWIP_TCP
+  tcp_init();
+#endif /* LWIP_TCP */
+#if LWIP_SNMP
+  snmp_init();
+#endif /* LWIP_SNMP */
+#if LWIP_AUTOIP
+  autoip_init();
+#endif /* LWIP_AUTOIP */
+#if LWIP_IGMP
+  igmp_init();
+#endif /* LWIP_IGMP */
+#if LWIP_DNS
+  dns_init();
+#endif /* LWIP_DNS */
+
+#if LWIP_TIMERS
+  sys_timeouts_init();
+#endif /* LWIP_TIMERS */
+}

src/lwip-1.4.1/src/core/ipv4/autoip.c

@@ -0,0 +1,528 @@
+/**
+ * @file
+ * AutoIP Automatic LinkLocal IP Configuration
+ *
+ */
+
+/*
+ *
+ * Copyright (c) 2007 Dominik Spies <kontakt@dspies.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * Author: Dominik Spies <kontakt@dspies.de>
+ *
+ * This is a AutoIP implementation for the lwIP TCP/IP stack. It aims to conform
+ * with RFC 3927.
+ *
+ *
+ * Please coordinate changes and requests with Dominik Spies
+ * <kontakt@dspies.de>
+ */
+
+/*******************************************************************************
+ * USAGE:
+ * 
+ * define LWIP_AUTOIP 1  in your lwipopts.h
+ * 
+ * If you don't use tcpip.c (so, don't call, you don't call tcpip_init):
+ * - First, call autoip_init().
+ * - call autoip_tmr() all AUTOIP_TMR_INTERVAL msces,
+ *   that should be defined in autoip.h.
+ *   I recommend a value of 100. The value must divide 1000 with a remainder almost 0.
+ *   Possible values are 1000, 500, 333, 250, 200, 166, 142, 125, 111, 100 ....
+ *
+ * Without DHCP:
+ * - Call autoip_start() after netif_add().
+ * 
+ * With DHCP:
+ * - define LWIP_DHCP_AUTOIP_COOP 1 in your lwipopts.h.
+ * - Configure your DHCP Client.
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_AUTOIP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/mem.h"
+#include "lwip/udp.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+#include "lwip/autoip.h"
+#include "netif/etharp.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+/* 169.254.0.0 */
+#define AUTOIP_NET         0xA9FE0000
+/* 169.254.1.0 */
+#define AUTOIP_RANGE_START (AUTOIP_NET | 0x0100)
+/* 169.254.254.255 */
+#define AUTOIP_RANGE_END   (AUTOIP_NET | 0xFEFF)
+
+
+/** Pseudo random macro based on netif informations.
+ * You could use "rand()" from the C Library if you define LWIP_AUTOIP_RAND in lwipopts.h */
+#ifndef LWIP_AUTOIP_RAND
+#define LWIP_AUTOIP_RAND(netif) ( (((u32_t)((netif->hwaddr[5]) & 0xff) << 24) | \
+                                   ((u32_t)((netif->hwaddr[3]) & 0xff) << 16) | \
+                                   ((u32_t)((netif->hwaddr[2]) & 0xff) << 8) | \
+                                   ((u32_t)((netif->hwaddr[4]) & 0xff))) + \
+                                   (netif->autoip?netif->autoip->tried_llipaddr:0))
+#endif /* LWIP_AUTOIP_RAND */
+
+/**
+ * Macro that generates the initial IP address to be tried by AUTOIP.
+ * If you want to override this, define it to something else in lwipopts.h.
+ */
+#ifndef LWIP_AUTOIP_CREATE_SEED_ADDR
+#define LWIP_AUTOIP_CREATE_SEED_ADDR(netif) \
+  htonl(AUTOIP_RANGE_START + ((u32_t)(((u8_t)(netif->hwaddr[4])) | \
+                 ((u32_t)((u8_t)(netif->hwaddr[5]))) << 8)))
+#endif /* LWIP_AUTOIP_CREATE_SEED_ADDR */
+
+/* static functions */
+static void autoip_handle_arp_conflict(struct netif *netif);
+
+/* creates a pseudo random LL IP-Address for a network interface */
+static void autoip_create_addr(struct netif *netif, ip_addr_t *ipaddr);
+
+/* sends an ARP probe */
+static err_t autoip_arp_probe(struct netif *netif);
+
+/* sends an ARP announce */
+static err_t autoip_arp_announce(struct netif *netif);
+
+/* configure interface for use with current LL IP-Address */
+static err_t autoip_bind(struct netif *netif);
+
+/* start sending probes for llipaddr */
+static void autoip_start_probing(struct netif *netif);
+
+
+/** Set a statically allocated struct autoip to work with.
+ * Using this prevents autoip_start to allocate it using mem_malloc.
+ *
+ * @param netif the netif for which to set the struct autoip
+ * @param dhcp (uninitialised) dhcp struct allocated by the application
+ */
+void
+autoip_set_struct(struct netif *netif, struct autoip *autoip)
+{
+  LWIP_ASSERT("netif != NULL", netif != NULL);
+  LWIP_ASSERT("autoip != NULL", autoip != NULL);
+  LWIP_ASSERT("netif already has a struct autoip set", netif->autoip == NULL);
+
+  /* clear data structure */
+  memset(autoip, 0, sizeof(struct autoip));
+  /* autoip->state = AUTOIP_STATE_OFF; */
+  netif->autoip = autoip;
+}
+
+/** Restart AutoIP client and check the next address (conflict detected)
+ *
+ * @param netif The netif under AutoIP control
+ */
+static void
+autoip_restart(struct netif *netif)
+{
+  netif->autoip->tried_llipaddr++;
+  autoip_start(netif);
+}
+
+/**
+ * Handle a IP address conflict after an ARP conflict detection
+ */
+static void
+autoip_handle_arp_conflict(struct netif *netif)
+{
+  /* Somehow detect if we are defending or retreating */
+  unsigned char defend = 1; /* tbd */
+
+  if (defend) {
+    if (netif->autoip->lastconflict > 0) {
+      /* retreat, there was a conflicting ARP in the last
+       * DEFEND_INTERVAL seconds
+       */
+      LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
+        ("autoip_handle_arp_conflict(): we are defending, but in DEFEND_INTERVAL, retreating\n"));
+
+      /* TODO: close all TCP sessions */
+      autoip_restart(netif);
+    } else {
+      LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
+        ("autoip_handle_arp_conflict(): we are defend, send ARP Announce\n"));
+      autoip_arp_announce(netif);
+      netif->autoip->lastconflict = DEFEND_INTERVAL * AUTOIP_TICKS_PER_SECOND;
+    }
+  } else {
+    LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
+      ("autoip_handle_arp_conflict(): we do not defend, retreating\n"));
+    /* TODO: close all TCP sessions */
+    autoip_restart(netif);
+  }
+}
+
+/**
+ * Create an IP-Address out of range 169.254.1.0 to 169.254.254.255
+ *
+ * @param netif network interface on which create the IP-Address
+ * @param ipaddr ip address to initialize
+ */
+static void
+autoip_create_addr(struct netif *netif, ip_addr_t *ipaddr)
+{
+  /* Here we create an IP-Address out of range 169.254.1.0 to 169.254.254.255
+   * compliant to RFC 3927 Section 2.1
+   * We have 254 * 256 possibilities */
+
+  u32_t addr = ntohl(LWIP_AUTOIP_CREATE_SEED_ADDR(netif));
+  addr += netif->autoip->tried_llipaddr;
+  addr = AUTOIP_NET | (addr & 0xffff);
+  /* Now, 169.254.0.0 <= addr <= 169.254.255.255 */ 
+
+  if (addr < AUTOIP_RANGE_START) {
+    addr += AUTOIP_RANGE_END - AUTOIP_RANGE_START + 1;
+  }
+  if (addr > AUTOIP_RANGE_END) {
+    addr -= AUTOIP_RANGE_END - AUTOIP_RANGE_START + 1;
+  }
+  LWIP_ASSERT("AUTOIP address not in range", (addr >= AUTOIP_RANGE_START) &&
+    (addr <= AUTOIP_RANGE_END));
+  ip4_addr_set_u32(ipaddr, htonl(addr));
+  
+  LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
+    ("autoip_create_addr(): tried_llipaddr=%"U16_F", %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+    (u16_t)(netif->autoip->tried_llipaddr), ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr),
+    ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr)));
+}
+
+/**
+ * Sends an ARP probe from a network interface
+ *
+ * @param netif network interface used to send the probe
+ */
+static err_t
+autoip_arp_probe(struct netif *netif)
+{
+  return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, &ethbroadcast,
+    (struct eth_addr *)netif->hwaddr, IP_ADDR_ANY, &ethzero,
+    &netif->autoip->llipaddr, ARP_REQUEST);
+}
+
+/**
+ * Sends an ARP announce from a network interface
+ *
+ * @param netif network interface used to send the announce
+ */
+static err_t
+autoip_arp_announce(struct netif *netif)
+{
+  return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, &ethbroadcast,
+    (struct eth_addr *)netif->hwaddr, &netif->autoip->llipaddr, &ethzero,
+    &netif->autoip->llipaddr, ARP_REQUEST);
+}
+
+/**
+ * Configure interface for use with current LL IP-Address
+ *
+ * @param netif network interface to configure with current LL IP-Address
+ */
+static err_t
+autoip_bind(struct netif *netif)
+{
+  struct autoip *autoip = netif->autoip;
+  ip_addr_t sn_mask, gw_addr;
+
+  LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE,
+    ("autoip_bind(netif=%p) %c%c%"U16_F" %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+    (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num,
+    ip4_addr1_16(&autoip->llipaddr), ip4_addr2_16(&autoip->llipaddr),
+    ip4_addr3_16(&autoip->llipaddr), ip4_addr4_16(&autoip->llipaddr)));
+
+  IP4_ADDR(&sn_mask, 255, 255, 0, 0);
+  IP4_ADDR(&gw_addr, 0, 0, 0, 0);
+
+  netif_set_ipaddr(netif, &autoip->llipaddr);
+  netif_set_netmask(netif, &sn_mask);
+  netif_set_gw(netif, &gw_addr);  
+
+  /* bring the interface up */
+  netif_set_up(netif);
+
+  return ERR_OK;
+}
+
+/**
+ * Start AutoIP client
+ *
+ * @param netif network interface on which start the AutoIP client
+ */
+err_t
+autoip_start(struct netif *netif)
+{
+  struct autoip *autoip = netif->autoip;
+  err_t result = ERR_OK;
+
+  if (netif_is_up(netif)) {
+    netif_set_down(netif);
+  }
+
+  /* Set IP-Address, Netmask and Gateway to 0 to make sure that
+   * ARP Packets are formed correctly
+   */
+  ip_addr_set_zero(&netif->ip_addr);
+  ip_addr_set_zero(&netif->netmask);
+  ip_addr_set_zero(&netif->gw);
+
+  LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
+    ("autoip_start(netif=%p) %c%c%"U16_F"\n", (void*)netif, netif->name[0],
+    netif->name[1], (u16_t)netif->num));
+  if (autoip == NULL) {
+    /* no AutoIP client attached yet? */
+    LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE,
+      ("autoip_start(): starting new AUTOIP client\n"));
+    autoip = (struct autoip *)mem_malloc(sizeof(struct autoip));
+    if (autoip == NULL) {
+      LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE,
+        ("autoip_start(): could not allocate autoip\n"));
+      return ERR_MEM;
+    }
+    memset(autoip, 0, sizeof(struct autoip));
+    /* store this AutoIP client in the netif */
+    netif->autoip = autoip;
+    LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, ("autoip_start(): allocated autoip"));
+  } else {
+    autoip->state = AUTOIP_STATE_OFF;
+    autoip->ttw = 0;
+    autoip->sent_num = 0;
+    ip_addr_set_zero(&autoip->llipaddr);
+    autoip->lastconflict = 0;
+  }
+
+  autoip_create_addr(netif, &(autoip->llipaddr));
+  autoip_start_probing(netif);
+
+  return result;
+}
+
+static void
+autoip_start_probing(struct netif *netif)
+{
+  struct autoip *autoip = netif->autoip;
+
+  autoip->state = AUTOIP_STATE_PROBING;
+  autoip->sent_num = 0;
+  LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
+     ("autoip_start_probing(): changing state to PROBING: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+      ip4_addr1_16(&netif->autoip->llipaddr), ip4_addr2_16(&netif->autoip->llipaddr),
+      ip4_addr3_16(&netif->autoip->llipaddr), ip4_addr4_16(&netif->autoip->llipaddr)));
+
+  /* time to wait to first probe, this is randomly
+   * choosen out of 0 to PROBE_WAIT seconds.
+   * compliant to RFC 3927 Section 2.2.1
+   */
+  autoip->ttw = (u16_t)(LWIP_AUTOIP_RAND(netif) % (PROBE_WAIT * AUTOIP_TICKS_PER_SECOND));
+
+  /*
+   * if we tried more then MAX_CONFLICTS we must limit our rate for
+   * accquiring and probing address
+   * compliant to RFC 3927 Section 2.2.1
+   */
+  if (autoip->tried_llipaddr > MAX_CONFLICTS) {
+    autoip->ttw = RATE_LIMIT_INTERVAL * AUTOIP_TICKS_PER_SECOND;
+  }
+}
+
+/**
+ * Handle a possible change in the network configuration.
+ *
+ * If there is an AutoIP address configured, take the interface down
+ * and begin probing with the same address.
+ */
+void
+autoip_network_changed(struct netif *netif)
+{
+  if (netif->autoip && netif->autoip->state != AUTOIP_STATE_OFF) {
+    netif_set_down(netif);
+    autoip_start_probing(netif);
+  }
+}
+
+/**
+ * Stop AutoIP client
+ *
+ * @param netif network interface on which stop the AutoIP client
+ */
+err_t
+autoip_stop(struct netif *netif)
+{
+  netif->autoip->state = AUTOIP_STATE_OFF;
+  netif_set_down(netif);
+  return ERR_OK;
+}
+
+/**
+ * Has to be called in loop every AUTOIP_TMR_INTERVAL milliseconds
+ */
+void
+autoip_tmr()
+{
+  struct netif *netif = netif_list;
+  /* loop through netif's */
+  while (netif != NULL) {
+    /* only act on AutoIP configured interfaces */
+    if (netif->autoip != NULL) {
+      if (netif->autoip->lastconflict > 0) {
+        netif->autoip->lastconflict--;
+      }
+
+      LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE,
+        ("autoip_tmr() AutoIP-State: %"U16_F", ttw=%"U16_F"\n",
+        (u16_t)(netif->autoip->state), netif->autoip->ttw));
+
+      switch(netif->autoip->state) {
+        case AUTOIP_STATE_PROBING:
+          if (netif->autoip->ttw > 0) {
+            netif->autoip->ttw--;
+          } else {
+            if (netif->autoip->sent_num >= PROBE_NUM) {
+              netif->autoip->state = AUTOIP_STATE_ANNOUNCING;
+              netif->autoip->sent_num = 0;
+              netif->autoip->ttw = ANNOUNCE_WAIT * AUTOIP_TICKS_PER_SECOND;
+              LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
+                 ("autoip_tmr(): changing state to ANNOUNCING: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+                  ip4_addr1_16(&netif->autoip->llipaddr), ip4_addr2_16(&netif->autoip->llipaddr),
+                  ip4_addr3_16(&netif->autoip->llipaddr), ip4_addr4_16(&netif->autoip->llipaddr)));
+            } else {
+              autoip_arp_probe(netif);
+              LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE,
+                ("autoip_tmr() PROBING Sent Probe\n"));
+              netif->autoip->sent_num++;
+              /* calculate time to wait to next probe */
+              netif->autoip->ttw = (u16_t)((LWIP_AUTOIP_RAND(netif) %
+                ((PROBE_MAX - PROBE_MIN) * AUTOIP_TICKS_PER_SECOND) ) +
+                PROBE_MIN * AUTOIP_TICKS_PER_SECOND);
+            }
+          }
+          break;
+
+        case AUTOIP_STATE_ANNOUNCING:
+          if (netif->autoip->ttw > 0) {
+            netif->autoip->ttw--;
+          } else {
+            if (netif->autoip->sent_num == 0) {
+             /* We are here the first time, so we waited ANNOUNCE_WAIT seconds
+              * Now we can bind to an IP address and use it.
+              *
+              * autoip_bind calls netif_set_up. This triggers a gratuitous ARP
+              * which counts as an announcement.
+              */
+              autoip_bind(netif);
+            } else {
+              autoip_arp_announce(netif);
+              LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE,
+                ("autoip_tmr() ANNOUNCING Sent Announce\n"));
+            }
+            netif->autoip->ttw = ANNOUNCE_INTERVAL * AUTOIP_TICKS_PER_SECOND;
+            netif->autoip->sent_num++;
+
+            if (netif->autoip->sent_num >= ANNOUNCE_NUM) {
+                netif->autoip->state = AUTOIP_STATE_BOUND;
+                netif->autoip->sent_num = 0;
+                netif->autoip->ttw = 0;
+                 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
+                    ("autoip_tmr(): changing state to BOUND: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+                     ip4_addr1_16(&netif->autoip->llipaddr), ip4_addr2_16(&netif->autoip->llipaddr),
+                     ip4_addr3_16(&netif->autoip->llipaddr), ip4_addr4_16(&netif->autoip->llipaddr)));
+            }
+          }
+          break;
+      }
+    }
+    /* proceed to next network interface */
+    netif = netif->next;
+  }
+}
+
+/**
+ * Handles every incoming ARP Packet, called by etharp_arp_input.
+ *
+ * @param netif network interface to use for autoip processing
+ * @param hdr Incoming ARP packet
+ */
+void
+autoip_arp_reply(struct netif *netif, struct etharp_hdr *hdr)
+{
+  LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, ("autoip_arp_reply()\n"));
+  if ((netif->autoip != NULL) && (netif->autoip->state != AUTOIP_STATE_OFF)) {
+   /* when ip.src == llipaddr && hw.src != netif->hwaddr
+    *
+    * when probing  ip.dst == llipaddr && hw.src != netif->hwaddr
+    * we have a conflict and must solve it
+    */
+    ip_addr_t sipaddr, dipaddr;
+    struct eth_addr netifaddr;
+    ETHADDR16_COPY(netifaddr.addr, netif->hwaddr);
+
+    /* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
+     * structure packing (not using structure copy which breaks strict-aliasing rules).
+     */
+    IPADDR2_COPY(&sipaddr, &hdr->sipaddr);
+    IPADDR2_COPY(&dipaddr, &hdr->dipaddr);
+      
+    if ((netif->autoip->state == AUTOIP_STATE_PROBING) ||
+        ((netif->autoip->state == AUTOIP_STATE_ANNOUNCING) &&
+         (netif->autoip->sent_num == 0))) {
+     /* RFC 3927 Section 2.2.1:
+      * from beginning to after ANNOUNCE_WAIT
+      * seconds we have a conflict if
+      * ip.src == llipaddr OR
+      * ip.dst == llipaddr && hw.src != own hwaddr
+      */
+      if ((ip_addr_cmp(&sipaddr, &netif->autoip->llipaddr)) ||
+          (ip_addr_cmp(&dipaddr, &netif->autoip->llipaddr) &&
+           !eth_addr_cmp(&netifaddr, &hdr->shwaddr))) {
+        LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | LWIP_DBG_LEVEL_WARNING,
+          ("autoip_arp_reply(): Probe Conflict detected\n"));
+        autoip_restart(netif);
+      }
+    } else {
+     /* RFC 3927 Section 2.5:
+      * in any state we have a conflict if
+      * ip.src == llipaddr && hw.src != own hwaddr
+      */
+      if (ip_addr_cmp(&sipaddr, &netif->autoip->llipaddr) &&
+          !eth_addr_cmp(&netifaddr, &hdr->shwaddr)) {
+        LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | LWIP_DBG_LEVEL_WARNING,
+          ("autoip_arp_reply(): Conflicting ARP-Packet detected\n"));
+        autoip_handle_arp_conflict(netif);
+      }
+    }
+  }
+}
+
+#endif /* LWIP_AUTOIP */

src/lwip-1.4.1/src/core/ipv4/icmp.c

@@ -0,0 +1,339 @@
+/**
+ * @file
+ * ICMP - Internet Control Message Protocol
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+/* Some ICMP messages should be passed to the transport protocols. This
+   is not implemented. */
+
+#include "lwip/opt.h"
+
+#if LWIP_ICMP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/icmp.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/ip.h"
+#include "lwip/def.h"
+#include "lwip/stats.h"
+#include "lwip/snmp.h"
+
+#include <string.h>
+
+/** Small optimization: set to 0 if incoming PBUF_POOL pbuf always can be
+ * used to modify and send a response packet (and to 1 if this is not the case,
+ * e.g. when link header is stripped of when receiving) */
+#ifndef LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN
+#define LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN 1
+#endif /* LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN */
+
+/* The amount of data from the original packet to return in a dest-unreachable */
+#define ICMP_DEST_UNREACH_DATASIZE 8
+
+static void icmp_send_response(struct pbuf *p, u8_t type, u8_t code);
+
+/**
+ * Processes ICMP input packets, called from ip_input().
+ *
+ * Currently only processes icmp echo requests and sends
+ * out the echo response.
+ *
+ * @param p the icmp echo request packet, p->payload pointing to the ip header
+ * @param inp the netif on which this packet was received
+ */
+void
+icmp_input(struct pbuf *p, struct netif *inp)
+{
+  u8_t type;
+#ifdef LWIP_DEBUG
+  u8_t code;
+#endif /* LWIP_DEBUG */
+  struct icmp_echo_hdr *iecho;
+  struct ip_hdr *iphdr;
+  s16_t hlen;
+
+  ICMP_STATS_INC(icmp.recv);
+  snmp_inc_icmpinmsgs();
+
+
+  iphdr = (struct ip_hdr *)p->payload;
+  hlen = IPH_HL(iphdr) * 4;
+  if (pbuf_header(p, -hlen) || (p->tot_len < sizeof(u16_t)*2)) {
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: short ICMP (%"U16_F" bytes) received\n", p->tot_len));
+    goto lenerr;
+  }
+
+  type = *((u8_t *)p->payload);
+#ifdef LWIP_DEBUG
+  code = *(((u8_t *)p->payload)+1);
+#endif /* LWIP_DEBUG */
+  switch (type) {
+  case ICMP_ER:
+    /* This is OK, echo reply might have been parsed by a raw PCB
+       (as obviously, an echo request has been sent, too). */
+    break; 
+  case ICMP_ECHO:
+#if !LWIP_MULTICAST_PING || !LWIP_BROADCAST_PING
+    {
+      int accepted = 1;
+#if !LWIP_MULTICAST_PING
+      /* multicast destination address? */
+      if (ip_addr_ismulticast(&current_iphdr_dest)) {
+        accepted = 0;
+      }
+#endif /* LWIP_MULTICAST_PING */
+#if !LWIP_BROADCAST_PING
+      /* broadcast destination address? */
+      if (ip_addr_isbroadcast(&current_iphdr_dest, inp)) {
+        accepted = 0;
+      }
+#endif /* LWIP_BROADCAST_PING */
+      /* broadcast or multicast destination address not acceptd? */
+      if (!accepted) {
+        LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: Not echoing to multicast or broadcast pings\n"));
+        ICMP_STATS_INC(icmp.err);
+        pbuf_free(p);
+        return;
+      }
+    }
+#endif /* !LWIP_MULTICAST_PING || !LWIP_BROADCAST_PING */
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: ping\n"));
+    if (p->tot_len < sizeof(struct icmp_echo_hdr)) {
+      LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: bad ICMP echo received\n"));
+      goto lenerr;
+    }
+    if (inet_chksum_pbuf(p) != 0) {
+      LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: checksum failed for received ICMP echo\n"));
+      pbuf_free(p);
+      ICMP_STATS_INC(icmp.chkerr);
+      snmp_inc_icmpinerrors();
+      return;
+    }
+#if LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN
+    if (pbuf_header(p, (PBUF_IP_HLEN + PBUF_LINK_HLEN))) {
+      /* p is not big enough to contain link headers
+       * allocate a new one and copy p into it
+       */
+      struct pbuf *r;
+      /* switch p->payload to ip header */
+      if (pbuf_header(p, hlen)) {
+        LWIP_ASSERT("icmp_input: moving p->payload to ip header failed\n", 0);
+        goto memerr;
+      }
+      /* allocate new packet buffer with space for link headers */
+      r = pbuf_alloc(PBUF_LINK, p->tot_len, PBUF_RAM);
+      if (r == NULL) {
+        LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: allocating new pbuf failed\n"));
+        goto memerr;
+      }
+      LWIP_ASSERT("check that first pbuf can hold struct the ICMP header",
+                  (r->len >= hlen + sizeof(struct icmp_echo_hdr)));
+      /* copy the whole packet including ip header */
+      if (pbuf_copy(r, p) != ERR_OK) {
+        LWIP_ASSERT("icmp_input: copying to new pbuf failed\n", 0);
+        goto memerr;
+      }
+      iphdr = (struct ip_hdr *)r->payload;
+      /* switch r->payload back to icmp header */
+      if (pbuf_header(r, -hlen)) {
+        LWIP_ASSERT("icmp_input: restoring original p->payload failed\n", 0);
+        goto memerr;
+      }
+      /* free the original p */
+      pbuf_free(p);
+      /* we now have an identical copy of p that has room for link headers */
+      p = r;
+    } else {
+      /* restore p->payload to point to icmp header */
+      if (pbuf_header(p, -(s16_t)(PBUF_IP_HLEN + PBUF_LINK_HLEN))) {
+        LWIP_ASSERT("icmp_input: restoring original p->payload failed\n", 0);
+        goto memerr;
+      }
+    }
+#endif /* LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN */
+    /* At this point, all checks are OK. */
+    /* We generate an answer by switching the dest and src ip addresses,
+     * setting the icmp type to ECHO_RESPONSE and updating the checksum. */
+    iecho = (struct icmp_echo_hdr *)p->payload;
+    ip_addr_copy(iphdr->src, *ip_current_dest_addr());
+    ip_addr_copy(iphdr->dest, *ip_current_src_addr());
+    ICMPH_TYPE_SET(iecho, ICMP_ER);
+#if CHECKSUM_GEN_ICMP
+    /* adjust the checksum */
+    if (iecho->chksum >= PP_HTONS(0xffffU - (ICMP_ECHO << 8))) {
+      iecho->chksum += PP_HTONS(ICMP_ECHO << 8) + 1;
+    } else {
+      iecho->chksum += PP_HTONS(ICMP_ECHO << 8);
+    }
+#else /* CHECKSUM_GEN_ICMP */
+    iecho->chksum = 0;
+#endif /* CHECKSUM_GEN_ICMP */
+
+    /* Set the correct TTL and recalculate the header checksum. */
+    IPH_TTL_SET(iphdr, ICMP_TTL);
+    IPH_CHKSUM_SET(iphdr, 0);
+#if CHECKSUM_GEN_IP
+    IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, IP_HLEN));
+#endif /* CHECKSUM_GEN_IP */
+
+    ICMP_STATS_INC(icmp.xmit);
+    /* increase number of messages attempted to send */
+    snmp_inc_icmpoutmsgs();
+    /* increase number of echo replies attempted to send */
+    snmp_inc_icmpoutechoreps();
+
+    if(pbuf_header(p, hlen)) {
+      LWIP_ASSERT("Can't move over header in packet", 0);
+    } else {
+      err_t ret;
+      /* send an ICMP packet, src addr is the dest addr of the curren packet */
+      ret = ip_output_if(p, ip_current_dest_addr(), IP_HDRINCL,
+                   ICMP_TTL, 0, IP_PROTO_ICMP, inp);
+      if (ret != ERR_OK) {
+        LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: ip_output_if returned an error: %c.\n", ret));
+      }
+    }
+    break;
+  default:
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: ICMP type %"S16_F" code %"S16_F" not supported.\n", 
+                (s16_t)type, (s16_t)code));
+    ICMP_STATS_INC(icmp.proterr);
+    ICMP_STATS_INC(icmp.drop);
+  }
+  pbuf_free(p);
+  return;
+lenerr:
+  pbuf_free(p);
+  ICMP_STATS_INC(icmp.lenerr);
+  snmp_inc_icmpinerrors();
+  return;
+#if LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN
+memerr:
+  pbuf_free(p);
+  ICMP_STATS_INC(icmp.err);
+  snmp_inc_icmpinerrors();
+  return;
+#endif /* LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN */
+}
+
+/**
+ * Send an icmp 'destination unreachable' packet, called from ip_input() if
+ * the transport layer protocol is unknown and from udp_input() if the local
+ * port is not bound.
+ *
+ * @param p the input packet for which the 'unreachable' should be sent,
+ *          p->payload pointing to the IP header
+ * @param t type of the 'unreachable' packet
+ */
+void
+icmp_dest_unreach(struct pbuf *p, enum icmp_dur_type t)
+{
+  icmp_send_response(p, ICMP_DUR, t);
+}
+
+#if IP_FORWARD || IP_REASSEMBLY
+/**
+ * Send a 'time exceeded' packet, called from ip_forward() if TTL is 0.
+ *
+ * @param p the input packet for which the 'time exceeded' should be sent,
+ *          p->payload pointing to the IP header
+ * @param t type of the 'time exceeded' packet
+ */
+void
+icmp_time_exceeded(struct pbuf *p, enum icmp_te_type t)
+{
+  icmp_send_response(p, ICMP_TE, t);
+}
+
+#endif /* IP_FORWARD || IP_REASSEMBLY */
+
+/**
+ * Send an icmp packet in response to an incoming packet.
+ *
+ * @param p the input packet for which the 'unreachable' should be sent,
+ *          p->payload pointing to the IP header
+ * @param type Type of the ICMP header
+ * @param code Code of the ICMP header
+ */
+static void
+icmp_send_response(struct pbuf *p, u8_t type, u8_t code)
+{
+  struct pbuf *q;
+  struct ip_hdr *iphdr;
+  /* we can use the echo header here */
+  struct icmp_echo_hdr *icmphdr;
+  ip_addr_t iphdr_src;
+
+  /* ICMP header + IP header + 8 bytes of data */
+  q = pbuf_alloc(PBUF_IP, sizeof(struct icmp_echo_hdr) + IP_HLEN + ICMP_DEST_UNREACH_DATASIZE,
+                 PBUF_RAM);
+  if (q == NULL) {
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp_time_exceeded: failed to allocate pbuf for ICMP packet.\n"));
+    return;
+  }
+  LWIP_ASSERT("check that first pbuf can hold icmp message",
+             (q->len >= (sizeof(struct icmp_echo_hdr) + IP_HLEN + ICMP_DEST_UNREACH_DATASIZE)));
+
+  iphdr = (struct ip_hdr *)p->payload;
+  LWIP_DEBUGF(ICMP_DEBUG, ("icmp_time_exceeded from "));
+  ip_addr_debug_print(ICMP_DEBUG, &(iphdr->src));
+  LWIP_DEBUGF(ICMP_DEBUG, (" to "));
+  ip_addr_debug_print(ICMP_DEBUG, &(iphdr->dest));
+  LWIP_DEBUGF(ICMP_DEBUG, ("\n"));
+
+  icmphdr = (struct icmp_echo_hdr *)q->payload;
+  icmphdr->type = type;
+  icmphdr->code = code;
+  icmphdr->id = 0;
+  icmphdr->seqno = 0;
+
+  /* copy fields from original packet */
+  SMEMCPY((u8_t *)q->payload + sizeof(struct icmp_echo_hdr), (u8_t *)p->payload,
+          IP_HLEN + ICMP_DEST_UNREACH_DATASIZE);
+
+  /* calculate checksum */
+  icmphdr->chksum = 0;
+  icmphdr->chksum = inet_chksum(icmphdr, q->len);
+  ICMP_STATS_INC(icmp.xmit);
+  /* increase number of messages attempted to send */
+  snmp_inc_icmpoutmsgs();
+  /* increase number of destination unreachable messages attempted to send */
+  snmp_inc_icmpouttimeexcds();
+  ip_addr_copy(iphdr_src, iphdr->src);
+  ip_output(q, NULL, &iphdr_src, ICMP_TTL, 0, IP_PROTO_ICMP);
+  pbuf_free(q);
+}
+
+#endif /* LWIP_ICMP */

src/lwip-1.4.1/src/core/ipv4/igmp.c

@@ -0,0 +1,805 @@
+/**
+ * @file
+ * IGMP - Internet Group Management Protocol
+ *
+ */
+
+/*
+ * Copyright (c) 2002 CITEL Technologies Ltd.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions 
+ * are met: 
+ * 1. Redistributions of source code must retain the above copyright 
+ *    notice, this list of conditions and the following disclaimer. 
+ * 2. Redistributions in binary form must reproduce the above copyright 
+ *    notice, this list of conditions and the following disclaimer in the 
+ *    documentation and/or other materials provided with the distribution. 
+ * 3. Neither the name of CITEL Technologies Ltd nor the names of its contributors 
+ *    may be used to endorse or promote products derived from this software 
+ *    without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY CITEL TECHNOLOGIES AND CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+ * ARE DISCLAIMED.  IN NO EVENT SHALL CITEL TECHNOLOGIES OR CONTRIBUTORS BE LIABLE 
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
+ * SUCH DAMAGE. 
+ *
+ * This file is a contribution to the lwIP TCP/IP stack.
+ * The Swedish Institute of Computer Science and Adam Dunkels
+ * are specifically granted permission to redistribute this
+ * source code.
+*/
+
+/*-------------------------------------------------------------
+Note 1)
+Although the rfc requires V1 AND V2 capability
+we will only support v2 since now V1 is very old (August 1989)
+V1 can be added if required
+
+a debug print and statistic have been implemented to
+show this up.
+-------------------------------------------------------------
+-------------------------------------------------------------
+Note 2)
+A query for a specific group address (as opposed to ALLHOSTS)
+has now been implemented as I am unsure if it is required
+
+a debug print and statistic have been implemented to
+show this up.
+-------------------------------------------------------------
+-------------------------------------------------------------
+Note 3)
+The router alert rfc 2113 is implemented in outgoing packets
+but not checked rigorously incoming
+-------------------------------------------------------------
+Steve Reynolds
+------------------------------------------------------------*/
+
+/*-----------------------------------------------------------------------------
+ * RFC 988  - Host extensions for IP multicasting                         - V0
+ * RFC 1054 - Host extensions for IP multicasting                         -
+ * RFC 1112 - Host extensions for IP multicasting                         - V1
+ * RFC 2236 - Internet Group Management Protocol, Version 2               - V2  <- this code is based on this RFC (it's the "de facto" standard)
+ * RFC 3376 - Internet Group Management Protocol, Version 3               - V3
+ * RFC 4604 - Using Internet Group Management Protocol Version 3...       - V3+
+ * RFC 2113 - IP Router Alert Option                                      - 
+ *----------------------------------------------------------------------------*/
+
+/*-----------------------------------------------------------------------------
+ * Includes
+ *----------------------------------------------------------------------------*/
+
+#include "lwip/opt.h"
+
+#if LWIP_IGMP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/igmp.h"
+#include "lwip/debug.h"
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/ip.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/netif.h"
+#include "lwip/icmp.h"
+#include "lwip/udp.h"
+#include "lwip/tcp.h"
+#include "lwip/stats.h"
+
+#include "string.h"
+
+/* 
+ * IGMP constants
+ */
+#define IGMP_TTL                       1
+#define IGMP_MINLEN                    8
+#define ROUTER_ALERT                   0x9404U
+#define ROUTER_ALERTLEN                4
+
+/*
+ * IGMP message types, including version number.
+ */
+#define IGMP_MEMB_QUERY                0x11 /* Membership query         */
+#define IGMP_V1_MEMB_REPORT            0x12 /* Ver. 1 membership report */
+#define IGMP_V2_MEMB_REPORT            0x16 /* Ver. 2 membership report */
+#define IGMP_LEAVE_GROUP               0x17 /* Leave-group message      */
+
+/* Group  membership states */
+#define IGMP_GROUP_NON_MEMBER          0
+#define IGMP_GROUP_DELAYING_MEMBER     1
+#define IGMP_GROUP_IDLE_MEMBER         2
+
+/**
+ * IGMP packet format.
+ */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct igmp_msg {
+ PACK_STRUCT_FIELD(u8_t           igmp_msgtype);
+ PACK_STRUCT_FIELD(u8_t           igmp_maxresp);
+ PACK_STRUCT_FIELD(u16_t          igmp_checksum);
+ PACK_STRUCT_FIELD(ip_addr_p_t    igmp_group_address);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+
+static struct igmp_group *igmp_lookup_group(struct netif *ifp, ip_addr_t *addr);
+static err_t  igmp_remove_group(struct igmp_group *group);
+static void   igmp_timeout( struct igmp_group *group);
+static void   igmp_start_timer(struct igmp_group *group, u8_t max_time);
+static void   igmp_delaying_member(struct igmp_group *group, u8_t maxresp);
+static err_t  igmp_ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, struct netif *netif);
+static void   igmp_send(struct igmp_group *group, u8_t type);
+
+
+static struct igmp_group* igmp_group_list;
+static ip_addr_t     allsystems;
+static ip_addr_t     allrouters;
+
+
+/**
+ * Initialize the IGMP module
+ */
+void
+igmp_init(void)
+{
+  LWIP_DEBUGF(IGMP_DEBUG, ("igmp_init: initializing\n"));
+
+  IP4_ADDR(&allsystems, 224, 0, 0, 1);
+  IP4_ADDR(&allrouters, 224, 0, 0, 2);
+}
+
+#ifdef LWIP_DEBUG
+/**
+ * Dump global IGMP groups list
+ */
+void
+igmp_dump_group_list()
+{ 
+  struct igmp_group *group = igmp_group_list;
+
+  while (group != NULL) {
+    LWIP_DEBUGF(IGMP_DEBUG, ("igmp_dump_group_list: [%"U32_F"] ", (u32_t)(group->group_state)));
+    ip_addr_debug_print(IGMP_DEBUG, &group->group_address);
+    LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", group->netif));
+    group = group->next;
+  }
+  LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
+}
+#else
+#define igmp_dump_group_list()
+#endif /* LWIP_DEBUG */
+
+/**
+ * Start IGMP processing on interface
+ *
+ * @param netif network interface on which start IGMP processing
+ */
+err_t
+igmp_start(struct netif *netif)
+{
+  struct igmp_group* group;
+
+  LWIP_DEBUGF(IGMP_DEBUG, ("igmp_start: starting IGMP processing on if %p\n", netif));
+
+  group = igmp_lookup_group(netif, &allsystems);
+
+  if (group != NULL) {
+    group->group_state = IGMP_GROUP_IDLE_MEMBER;
+    group->use++;
+
+    /* Allow the igmp messages at the MAC level */
+    if (netif->igmp_mac_filter != NULL) {
+      LWIP_DEBUGF(IGMP_DEBUG, ("igmp_start: igmp_mac_filter(ADD "));
+      ip_addr_debug_print(IGMP_DEBUG, &allsystems);
+      LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", netif));
+      netif->igmp_mac_filter(netif, &allsystems, IGMP_ADD_MAC_FILTER);
+    }
+
+    return ERR_OK;
+  }
+
+  return ERR_MEM;
+}
+
+/**
+ * Stop IGMP processing on interface
+ *
+ * @param netif network interface on which stop IGMP processing
+ */
+err_t
+igmp_stop(struct netif *netif)
+{
+  struct igmp_group *group = igmp_group_list;
+  struct igmp_group *prev  = NULL;
+  struct igmp_group *next;
+
+  /* look for groups joined on this interface further down the list */
+  while (group != NULL) {
+    next = group->next;
+    /* is it a group joined on this interface? */
+    if (group->netif == netif) {
+      /* is it the first group of the list? */
+      if (group == igmp_group_list) {
+        igmp_group_list = next;
+      }
+      /* is there a "previous" group defined? */
+      if (prev != NULL) {
+        prev->next = next;
+      }
+      /* disable the group at the MAC level */
+      if (netif->igmp_mac_filter != NULL) {
+        LWIP_DEBUGF(IGMP_DEBUG, ("igmp_stop: igmp_mac_filter(DEL "));
+        ip_addr_debug_print(IGMP_DEBUG, &group->group_address);
+        LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", netif));
+        netif->igmp_mac_filter(netif, &(group->group_address), IGMP_DEL_MAC_FILTER);
+      }
+      /* free group */
+      memp_free(MEMP_IGMP_GROUP, group);
+    } else {
+      /* change the "previous" */
+      prev = group;
+    }
+    /* move to "next" */
+    group = next;
+  }
+  return ERR_OK;
+}
+
+/**
+ * Report IGMP memberships for this interface
+ *
+ * @param netif network interface on which report IGMP memberships
+ */
+void
+igmp_report_groups(struct netif *netif)
+{
+  struct igmp_group *group = igmp_group_list;
+
+  LWIP_DEBUGF(IGMP_DEBUG, ("igmp_report_groups: sending IGMP reports on if %p\n", netif));
+
+  while (group != NULL) {
+    if (group->netif == netif) {
+      igmp_delaying_member(group, IGMP_JOIN_DELAYING_MEMBER_TMR);
+    }
+    group = group->next;
+  }
+}
+
+/**
+ * Search for a group in the global igmp_group_list
+ *
+ * @param ifp the network interface for which to look
+ * @param addr the group ip address to search for
+ * @return a struct igmp_group* if the group has been found,
+ *         NULL if the group wasn't found.
+ */
+struct igmp_group *
+igmp_lookfor_group(struct netif *ifp, ip_addr_t *addr)
+{
+  struct igmp_group *group = igmp_group_list;
+
+  while (group != NULL) {
+    if ((group->netif == ifp) && (ip_addr_cmp(&(group->group_address), addr))) {
+      return group;
+    }
+    group = group->next;
+  }
+
+  /* to be clearer, we return NULL here instead of
+   * 'group' (which is also NULL at this point).
+   */
+  return NULL;
+}
+
+/**
+ * Search for a specific igmp group and create a new one if not found-
+ *
+ * @param ifp the network interface for which to look
+ * @param addr the group ip address to search
+ * @return a struct igmp_group*,
+ *         NULL on memory error.
+ */
+struct igmp_group *
+igmp_lookup_group(struct netif *ifp, ip_addr_t *addr)
+{
+  struct igmp_group *group = igmp_group_list;
+  
+  /* Search if the group already exists */
+  group = igmp_lookfor_group(ifp, addr);
+  if (group != NULL) {
+    /* Group already exists. */
+    return group;
+  }
+
+  /* Group doesn't exist yet, create a new one */
+  group = (struct igmp_group *)memp_malloc(MEMP_IGMP_GROUP);
+  if (group != NULL) {
+    group->netif              = ifp;
+    ip_addr_set(&(group->group_address), addr);
+    group->timer              = 0; /* Not running */
+    group->group_state        = IGMP_GROUP_NON_MEMBER;
+    group->last_reporter_flag = 0;
+    group->use                = 0;
+    group->next               = igmp_group_list;
+    
+    igmp_group_list = group;
+  }
+
+  LWIP_DEBUGF(IGMP_DEBUG, ("igmp_lookup_group: %sallocated a new group with address ", (group?"":"impossible to ")));
+  ip_addr_debug_print(IGMP_DEBUG, addr);
+  LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", ifp));
+
+  return group;
+}
+
+/**
+ * Remove a group in the global igmp_group_list
+ *
+ * @param group the group to remove from the global igmp_group_list
+ * @return ERR_OK if group was removed from the list, an err_t otherwise
+ */
+static err_t
+igmp_remove_group(struct igmp_group *group)
+{
+  err_t err = ERR_OK;
+
+  /* Is it the first group? */
+  if (igmp_group_list == group) {
+    igmp_group_list = group->next;
+  } else {
+    /* look for group further down the list */
+    struct igmp_group *tmpGroup;
+    for (tmpGroup = igmp_group_list; tmpGroup != NULL; tmpGroup = tmpGroup->next) {
+      if (tmpGroup->next == group) {
+        tmpGroup->next = group->next;
+        break;
+      }
+    }
+    /* Group not found in the global igmp_group_list */
+    if (tmpGroup == NULL)
+      err = ERR_ARG;
+  }
+  /* free group */
+  memp_free(MEMP_IGMP_GROUP, group);
+
+  return err;
+}
+
+/**
+ * Called from ip_input() if a new IGMP packet is received.
+ *
+ * @param p received igmp packet, p->payload pointing to the ip header
+ * @param inp network interface on which the packet was received
+ * @param dest destination ip address of the igmp packet
+ */
+void
+igmp_input(struct pbuf *p, struct netif *inp, ip_addr_t *dest)
+{
+  struct ip_hdr *    iphdr;
+  struct igmp_msg*   igmp;
+  struct igmp_group* group;
+  struct igmp_group* groupref;
+
+  IGMP_STATS_INC(igmp.recv);
+
+  /* Note that the length CAN be greater than 8 but only 8 are used - All are included in the checksum */    
+  iphdr = (struct ip_hdr *)p->payload;
+  if (pbuf_header(p, -(s16_t)(IPH_HL(iphdr) * 4)) || (p->len < IGMP_MINLEN)) {
+    pbuf_free(p);
+    IGMP_STATS_INC(igmp.lenerr);
+    LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: length error\n"));
+    return;
+  }
+
+  LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: message from "));
+  ip_addr_debug_print(IGMP_DEBUG, &(iphdr->src));
+  LWIP_DEBUGF(IGMP_DEBUG, (" to address "));
+  ip_addr_debug_print(IGMP_DEBUG, &(iphdr->dest));
+  LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", inp));
+
+  /* Now calculate and check the checksum */
+  igmp = (struct igmp_msg *)p->payload;
+  if (inet_chksum(igmp, p->len)) {
+    pbuf_free(p);
+    IGMP_STATS_INC(igmp.chkerr);
+    LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: checksum error\n"));
+    return;
+  }
+
+  /* Packet is ok so find an existing group */
+  group = igmp_lookfor_group(inp, dest); /* use the destination IP address of incoming packet */
+  
+  /* If group can be found or create... */
+  if (!group) {
+    pbuf_free(p);
+    IGMP_STATS_INC(igmp.drop);
+    LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP frame not for us\n"));
+    return;
+  }
+
+  /* NOW ACT ON THE INCOMING MESSAGE TYPE... */
+  switch (igmp->igmp_msgtype) {
+   case IGMP_MEMB_QUERY: {
+     /* IGMP_MEMB_QUERY to the "all systems" address ? */
+     if ((ip_addr_cmp(dest, &allsystems)) && ip_addr_isany(&igmp->igmp_group_address)) {
+       /* THIS IS THE GENERAL QUERY */
+       LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: General IGMP_MEMB_QUERY on \"ALL SYSTEMS\" address (224.0.0.1) [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
+
+       if (igmp->igmp_maxresp == 0) {
+         IGMP_STATS_INC(igmp.rx_v1);
+         LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: got an all hosts query with time== 0 - this is V1 and not implemented - treat as v2\n"));
+         igmp->igmp_maxresp = IGMP_V1_DELAYING_MEMBER_TMR;
+       } else {
+         IGMP_STATS_INC(igmp.rx_general);
+       }
+
+       groupref = igmp_group_list;
+       while (groupref) {
+         /* Do not send messages on the all systems group address! */
+         if ((groupref->netif == inp) && (!(ip_addr_cmp(&(groupref->group_address), &allsystems)))) {
+           igmp_delaying_member(groupref, igmp->igmp_maxresp);
+         }
+         groupref = groupref->next;
+       }
+     } else {
+       /* IGMP_MEMB_QUERY to a specific group ? */
+       if (!ip_addr_isany(&igmp->igmp_group_address)) {
+         LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP_MEMB_QUERY to a specific group "));
+         ip_addr_debug_print(IGMP_DEBUG, &igmp->igmp_group_address);
+         if (ip_addr_cmp(dest, &allsystems)) {
+           ip_addr_t groupaddr;
+           LWIP_DEBUGF(IGMP_DEBUG, (" using \"ALL SYSTEMS\" address (224.0.0.1) [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
+           /* we first need to re-look for the group since we used dest last time */
+           ip_addr_copy(groupaddr, igmp->igmp_group_address);
+           group = igmp_lookfor_group(inp, &groupaddr);
+         } else {
+           LWIP_DEBUGF(IGMP_DEBUG, (" with the group address as destination [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
+         }
+
+         if (group != NULL) {
+           IGMP_STATS_INC(igmp.rx_group);
+           igmp_delaying_member(group, igmp->igmp_maxresp);
+         } else {
+           IGMP_STATS_INC(igmp.drop);
+         }
+       } else {
+         IGMP_STATS_INC(igmp.proterr);
+       }
+     }
+     break;
+   }
+   case IGMP_V2_MEMB_REPORT: {
+     LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP_V2_MEMB_REPORT\n"));
+     IGMP_STATS_INC(igmp.rx_report);
+     if (group->group_state == IGMP_GROUP_DELAYING_MEMBER) {
+       /* This is on a specific group we have already looked up */
+       group->timer = 0; /* stopped */
+       group->group_state = IGMP_GROUP_IDLE_MEMBER;
+       group->last_reporter_flag = 0;
+     }
+     break;
+   }
+   default: {
+     LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: unexpected msg %d in state %d on group %p on if %p\n",
+       igmp->igmp_msgtype, group->group_state, &group, group->netif));
+     IGMP_STATS_INC(igmp.proterr);
+     break;
+   }
+  }
+
+  pbuf_free(p);
+  return;
+}
+
+/**
+ * Join a group on one network interface.
+ *
+ * @param ifaddr ip address of the network interface which should join a new group
+ * @param groupaddr the ip address of the group which to join
+ * @return ERR_OK if group was joined on the netif(s), an err_t otherwise
+ */
+err_t
+igmp_joingroup(ip_addr_t *ifaddr, ip_addr_t *groupaddr)
+{
+  err_t              err = ERR_VAL; /* no matching interface */
+  struct igmp_group *group;
+  struct netif      *netif;
+
+  /* make sure it is multicast address */
+  LWIP_ERROR("igmp_joingroup: attempt to join non-multicast address", ip_addr_ismulticast(groupaddr), return ERR_VAL;);
+  LWIP_ERROR("igmp_joingroup: attempt to join allsystems address", (!ip_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
+
+  /* loop through netif's */
+  netif = netif_list;
+  while (netif != NULL) {
+    /* Should we join this interface ? */
+    if ((netif->flags & NETIF_FLAG_IGMP) && ((ip_addr_isany(ifaddr) || ip_addr_cmp(&(netif->ip_addr), ifaddr)))) {
+      /* find group or create a new one if not found */
+      group = igmp_lookup_group(netif, groupaddr);
+
+      if (group != NULL) {
+        /* This should create a new group, check the state to make sure */
+        if (group->group_state != IGMP_GROUP_NON_MEMBER) {
+          LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: join to group not in state IGMP_GROUP_NON_MEMBER\n"));
+        } else {
+          /* OK - it was new group */
+          LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: join to new group: "));
+          ip_addr_debug_print(IGMP_DEBUG, groupaddr);
+          LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
+
+          /* If first use of the group, allow the group at the MAC level */
+          if ((group->use==0) && (netif->igmp_mac_filter != NULL)) {
+            LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: igmp_mac_filter(ADD "));
+            ip_addr_debug_print(IGMP_DEBUG, groupaddr);
+            LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", netif));
+            netif->igmp_mac_filter(netif, groupaddr, IGMP_ADD_MAC_FILTER);
+          }
+
+          IGMP_STATS_INC(igmp.tx_join);
+          igmp_send(group, IGMP_V2_MEMB_REPORT);
+
+          igmp_start_timer(group, IGMP_JOIN_DELAYING_MEMBER_TMR);
+
+          /* Need to work out where this timer comes from */
+          group->group_state = IGMP_GROUP_DELAYING_MEMBER;
+        }
+        /* Increment group use */
+        group->use++;
+        /* Join on this interface */
+        err = ERR_OK;
+      } else {
+        /* Return an error even if some network interfaces are joined */
+        /** @todo undo any other netif already joined */
+        LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: Not enought memory to join to group\n"));
+        return ERR_MEM;
+      }
+    }
+    /* proceed to next network interface */
+    netif = netif->next;
+  }
+
+  return err;
+}
+
+/**
+ * Leave a group on one network interface.
+ *
+ * @param ifaddr ip address of the network interface which should leave a group
+ * @param groupaddr the ip address of the group which to leave
+ * @return ERR_OK if group was left on the netif(s), an err_t otherwise
+ */
+err_t
+igmp_leavegroup(ip_addr_t *ifaddr, ip_addr_t *groupaddr)
+{
+  err_t              err = ERR_VAL; /* no matching interface */
+  struct igmp_group *group;
+  struct netif      *netif;
+
+  /* make sure it is multicast address */
+  LWIP_ERROR("igmp_leavegroup: attempt to leave non-multicast address", ip_addr_ismulticast(groupaddr), return ERR_VAL;);
+  LWIP_ERROR("igmp_leavegroup: attempt to leave allsystems address", (!ip_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
+
+  /* loop through netif's */
+  netif = netif_list;
+  while (netif != NULL) {
+    /* Should we leave this interface ? */
+    if ((netif->flags & NETIF_FLAG_IGMP) && ((ip_addr_isany(ifaddr) || ip_addr_cmp(&(netif->ip_addr), ifaddr)))) {
+      /* find group */
+      group = igmp_lookfor_group(netif, groupaddr);
+
+      if (group != NULL) {
+        /* Only send a leave if the flag is set according to the state diagram */
+        LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: Leaving group: "));
+        ip_addr_debug_print(IGMP_DEBUG, groupaddr);
+        LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
+
+        /* If there is no other use of the group */
+        if (group->use <= 1) {
+          /* If we are the last reporter for this group */
+          if (group->last_reporter_flag) {
+            LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: sending leaving group\n"));
+            IGMP_STATS_INC(igmp.tx_leave);
+            igmp_send(group, IGMP_LEAVE_GROUP);
+          }
+          
+          /* Disable the group at the MAC level */
+          if (netif->igmp_mac_filter != NULL) {
+            LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: igmp_mac_filter(DEL "));
+            ip_addr_debug_print(IGMP_DEBUG, groupaddr);
+            LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", netif));
+            netif->igmp_mac_filter(netif, groupaddr, IGMP_DEL_MAC_FILTER);
+          }
+          
+          LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: remove group: "));
+          ip_addr_debug_print(IGMP_DEBUG, groupaddr);
+          LWIP_DEBUGF(IGMP_DEBUG, ("\n"));          
+          
+          /* Free the group */
+          igmp_remove_group(group);
+        } else {
+          /* Decrement group use */
+          group->use--;
+        }
+        /* Leave on this interface */
+        err = ERR_OK;
+      } else {
+        /* It's not a fatal error on "leavegroup" */
+        LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: not member of group\n"));
+      }
+    }
+    /* proceed to next network interface */
+    netif = netif->next;
+  }
+
+  return err;
+}
+
+/**
+ * The igmp timer function (both for NO_SYS=1 and =0)
+ * Should be called every IGMP_TMR_INTERVAL milliseconds (100 ms is default).
+ */
+void
+igmp_tmr(void)
+{
+  struct igmp_group *group = igmp_group_list;
+
+  while (group != NULL) {
+    if (group->timer > 0) {
+      group->timer--;
+      if (group->timer == 0) {
+        igmp_timeout(group);
+      }
+    }
+    group = group->next;
+  }
+}
+
+/**
+ * Called if a timeout for one group is reached.
+ * Sends a report for this group.
+ *
+ * @param group an igmp_group for which a timeout is reached
+ */
+static void
+igmp_timeout(struct igmp_group *group)
+{
+  /* If the state is IGMP_GROUP_DELAYING_MEMBER then we send a report for this group */
+  if (group->group_state == IGMP_GROUP_DELAYING_MEMBER) {
+    LWIP_DEBUGF(IGMP_DEBUG, ("igmp_timeout: report membership for group with address "));
+    ip_addr_debug_print(IGMP_DEBUG, &(group->group_address));
+    LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", group->netif));
+
+    IGMP_STATS_INC(igmp.tx_report);
+    igmp_send(group, IGMP_V2_MEMB_REPORT);
+  }
+}
+
+/**
+ * Start a timer for an igmp group
+ *
+ * @param group the igmp_group for which to start a timer
+ * @param max_time the time in multiples of IGMP_TMR_INTERVAL (decrease with
+ *        every call to igmp_tmr())
+ */
+static void
+igmp_start_timer(struct igmp_group *group, u8_t max_time)
+{
+  /* ensure the input value is > 0 */
+  if (max_time == 0) {
+    max_time = 1;
+  }
+  /* ensure the random value is > 0 */
+  group->timer = (LWIP_RAND() % (max_time - 1)) + 1;
+}
+
+/**
+ * Delaying membership report for a group if necessary
+ *
+ * @param group the igmp_group for which "delaying" membership report
+ * @param maxresp query delay
+ */
+static void
+igmp_delaying_member(struct igmp_group *group, u8_t maxresp)
+{
+  if ((group->group_state == IGMP_GROUP_IDLE_MEMBER) ||
+     ((group->group_state == IGMP_GROUP_DELAYING_MEMBER) &&
+      ((group->timer == 0) || (maxresp < group->timer)))) {
+    igmp_start_timer(group, maxresp);
+    group->group_state = IGMP_GROUP_DELAYING_MEMBER;
+  }
+}
+
+
+/**
+ * Sends an IP packet on a network interface. This function constructs the IP header
+ * and calculates the IP header checksum. If the source IP address is NULL,
+ * the IP address of the outgoing network interface is filled in as source address.
+ *
+ * @param p the packet to send (p->payload points to the data, e.g. next
+            protocol header; if dest == IP_HDRINCL, p already includes an IP
+            header and p->payload points to that IP header)
+ * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
+ *         IP  address of the netif used to send is used as source address)
+ * @param dest the destination IP address to send the packet to
+ * @param ttl the TTL value to be set in the IP header
+ * @param proto the PROTOCOL to be set in the IP header
+ * @param netif the netif on which to send this packet
+ * @return ERR_OK if the packet was sent OK
+ *         ERR_BUF if p doesn't have enough space for IP/LINK headers
+ *         returns errors returned by netif->output
+ */
+static err_t
+igmp_ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, struct netif *netif)
+{
+  /* This is the "router alert" option */
+  u16_t ra[2];
+  ra[0] = PP_HTONS(ROUTER_ALERT);
+  ra[1] = 0x0000; /* Router shall examine packet */
+  IGMP_STATS_INC(igmp.xmit);
+  return ip_output_if_opt(p, src, dest, IGMP_TTL, 0, IP_PROTO_IGMP, netif, ra, ROUTER_ALERTLEN);
+}
+
+/**
+ * Send an igmp packet to a specific group.
+ *
+ * @param group the group to which to send the packet
+ * @param type the type of igmp packet to send
+ */
+static void
+igmp_send(struct igmp_group *group, u8_t type)
+{
+  struct pbuf*     p    = NULL;
+  struct igmp_msg* igmp = NULL;
+  ip_addr_t   src  = *IP_ADDR_ANY;
+  ip_addr_t*  dest = NULL;
+
+  /* IP header + "router alert" option + IGMP header */
+  p = pbuf_alloc(PBUF_TRANSPORT, IGMP_MINLEN, PBUF_RAM);
+  
+  if (p) {
+    igmp = (struct igmp_msg *)p->payload;
+    LWIP_ASSERT("igmp_send: check that first pbuf can hold struct igmp_msg",
+               (p->len >= sizeof(struct igmp_msg)));
+    ip_addr_copy(src, group->netif->ip_addr);
+     
+    if (type == IGMP_V2_MEMB_REPORT) {
+      dest = &(group->group_address);
+      ip_addr_copy(igmp->igmp_group_address, group->group_address);
+      group->last_reporter_flag = 1; /* Remember we were the last to report */
+    } else {
+      if (type == IGMP_LEAVE_GROUP) {
+        dest = &allrouters;
+        ip_addr_copy(igmp->igmp_group_address, group->group_address);
+      }
+    }
+
+    if ((type == IGMP_V2_MEMB_REPORT) || (type == IGMP_LEAVE_GROUP)) {
+      igmp->igmp_msgtype  = type;
+      igmp->igmp_maxresp  = 0;
+      igmp->igmp_checksum = 0;
+      igmp->igmp_checksum = inet_chksum(igmp, IGMP_MINLEN);
+
+      igmp_ip_output_if(p, &src, dest, group->netif);
+    }
+
+    pbuf_free(p);
+  } else {
+    LWIP_DEBUGF(IGMP_DEBUG, ("igmp_send: not enough memory for igmp_send\n"));
+    IGMP_STATS_INC(igmp.memerr);
+  }
+}
+
+#endif /* LWIP_IGMP */

src/lwip-1.4.1/src/core/ipv4/inet.c

@@ -0,0 +1,42 @@
+/**
+ * @file
+ * Functions common to all TCP/IPv4 modules, such as the byte order functions.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/inet.h"
+

src/lwip-1.4.1/src/core/ipv4/inet_chksum.c

@@ -0,0 +1,450 @@
+/**
+ * @file
+ * Incluse internet checksum functions.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/inet_chksum.h"
+#include "lwip/def.h"
+
+#include <stddef.h>
+#include <string.h>
+
+/* These are some reference implementations of the checksum algorithm, with the
+ * aim of being simple, correct and fully portable. Checksumming is the
+ * first thing you would want to optimize for your platform. If you create
+ * your own version, link it in and in your cc.h put:
+ * 
+ * #define LWIP_CHKSUM <your_checksum_routine> 
+ *
+ * Or you can select from the implementations below by defining
+ * LWIP_CHKSUM_ALGORITHM to 1, 2 or 3.
+ */
+
+#ifndef LWIP_CHKSUM
+# define LWIP_CHKSUM lwip_standard_chksum
+# ifndef LWIP_CHKSUM_ALGORITHM
+#  define LWIP_CHKSUM_ALGORITHM 2
+# endif
+#endif
+/* If none set: */
+#ifndef LWIP_CHKSUM_ALGORITHM
+# define LWIP_CHKSUM_ALGORITHM 0
+#endif
+
+#if (LWIP_CHKSUM_ALGORITHM == 1) /* Version #1 */
+/**
+ * lwip checksum
+ *
+ * @param dataptr points to start of data to be summed at any boundary
+ * @param len length of data to be summed
+ * @return host order (!) lwip checksum (non-inverted Internet sum) 
+ *
+ * @note accumulator size limits summable length to 64k
+ * @note host endianess is irrelevant (p3 RFC1071)
+ */
+static u16_t
+lwip_standard_chksum(void *dataptr, u16_t len)
+{
+  u32_t acc;
+  u16_t src;
+  u8_t *octetptr;
+
+  acc = 0;
+  /* dataptr may be at odd or even addresses */
+  octetptr = (u8_t*)dataptr;
+  while (len > 1) {
+    /* declare first octet as most significant
+       thus assume network order, ignoring host order */
+    src = (*octetptr) << 8;
+    octetptr++;
+    /* declare second octet as least significant */
+    src |= (*octetptr);
+    octetptr++;
+    acc += src;
+    len -= 2;
+  }
+  if (len > 0) {
+    /* accumulate remaining octet */
+    src = (*octetptr) << 8;
+    acc += src;
+  }
+  /* add deferred carry bits */
+  acc = (acc >> 16) + (acc & 0x0000ffffUL);
+  if ((acc & 0xffff0000UL) != 0) {
+    acc = (acc >> 16) + (acc & 0x0000ffffUL);
+  }
+  /* This maybe a little confusing: reorder sum using htons()
+     instead of ntohs() since it has a little less call overhead.
+     The caller must invert bits for Internet sum ! */
+  return htons((u16_t)acc);
+}
+#endif
+
+#if (LWIP_CHKSUM_ALGORITHM == 2) /* Alternative version #2 */
+/*
+ * Curt McDowell
+ * Broadcom Corp.
+ * csm@broadcom.com
+ *
+ * IP checksum two bytes at a time with support for
+ * unaligned buffer.
+ * Works for len up to and including 0x20000.
+ * by Curt McDowell, Broadcom Corp. 12/08/2005
+ *
+ * @param dataptr points to start of data to be summed at any boundary
+ * @param len length of data to be summed
+ * @return host order (!) lwip checksum (non-inverted Internet sum) 
+ */
+
+static u16_t
+lwip_standard_chksum(void *dataptr, int len)
+{
+  u8_t *pb = (u8_t *)dataptr;
+  u16_t *ps, t = 0;
+  u32_t sum = 0;
+  int odd = ((mem_ptr_t)pb & 1);
+
+  /* Get aligned to u16_t */
+  if (odd && len > 0) {
+    ((u8_t *)&t)[1] = *pb++;
+    len--;
+  }
+
+  /* Add the bulk of the data */
+  ps = (u16_t *)(void *)pb;
+  while (len > 1) {
+    sum += *ps++;
+    len -= 2;
+  }
+
+  /* Consume left-over byte, if any */
+  if (len > 0) {
+    ((u8_t *)&t)[0] = *(u8_t *)ps;
+  }
+
+  /* Add end bytes */
+  sum += t;
+
+  /* Fold 32-bit sum to 16 bits
+     calling this twice is propably faster than if statements... */
+  sum = FOLD_U32T(sum);
+  sum = FOLD_U32T(sum);
+
+  /* Swap if alignment was odd */
+  if (odd) {
+    sum = SWAP_BYTES_IN_WORD(sum);
+  }
+
+  return (u16_t)sum;
+}
+#endif
+
+#if (LWIP_CHKSUM_ALGORITHM == 3) /* Alternative version #3 */
+/**
+ * An optimized checksum routine. Basically, it uses loop-unrolling on
+ * the checksum loop, treating the head and tail bytes specially, whereas
+ * the inner loop acts on 8 bytes at a time. 
+ *
+ * @arg start of buffer to be checksummed. May be an odd byte address.
+ * @len number of bytes in the buffer to be checksummed.
+ * @return host order (!) lwip checksum (non-inverted Internet sum) 
+ * 
+ * by Curt McDowell, Broadcom Corp. December 8th, 2005
+ */
+
+static u16_t
+lwip_standard_chksum(void *dataptr, int len)
+{
+  u8_t *pb = (u8_t *)dataptr;
+  u16_t *ps, t = 0;
+  u32_t *pl;
+  u32_t sum = 0, tmp;
+  /* starts at odd byte address? */
+  int odd = ((mem_ptr_t)pb & 1);
+
+  if (odd && len > 0) {
+    ((u8_t *)&t)[1] = *pb++;
+    len--;
+  }
+
+  ps = (u16_t *)pb;
+
+  if (((mem_ptr_t)ps & 3) && len > 1) {
+    sum += *ps++;
+    len -= 2;
+  }
+
+  pl = (u32_t *)ps;
+
+  while (len > 7)  {
+    tmp = sum + *pl++;          /* ping */
+    if (tmp < sum) {
+      tmp++;                    /* add back carry */
+    }
+
+    sum = tmp + *pl++;          /* pong */
+    if (sum < tmp) {
+      sum++;                    /* add back carry */
+    }
+
+    len -= 8;
+  }
+
+  /* make room in upper bits */
+  sum = FOLD_U32T(sum);
+
+  ps = (u16_t *)pl;
+
+  /* 16-bit aligned word remaining? */
+  while (len > 1) {
+    sum += *ps++;
+    len -= 2;
+  }
+
+  /* dangling tail byte remaining? */
+  if (len > 0) {                /* include odd byte */
+    ((u8_t *)&t)[0] = *(u8_t *)ps;
+  }
+
+  sum += t;                     /* add end bytes */
+
+  /* Fold 32-bit sum to 16 bits
+     calling this twice is propably faster than if statements... */
+  sum = FOLD_U32T(sum);
+  sum = FOLD_U32T(sum);
+
+  if (odd) {
+    sum = SWAP_BYTES_IN_WORD(sum);
+  }
+
+  return (u16_t)sum;
+}
+#endif
+
+/* inet_chksum_pseudo:
+ *
+ * Calculates the pseudo Internet checksum used by TCP and UDP for a pbuf chain.
+ * IP addresses are expected to be in network byte order.
+ *
+ * @param p chain of pbufs over that a checksum should be calculated (ip data part)
+ * @param src source ip address (used for checksum of pseudo header)
+ * @param dst destination ip address (used for checksum of pseudo header)
+ * @param proto ip protocol (used for checksum of pseudo header)
+ * @param proto_len length of the ip data part (used for checksum of pseudo header)
+ * @return checksum (as u16_t) to be saved directly in the protocol header
+ */
+u16_t
+inet_chksum_pseudo(struct pbuf *p,
+       ip_addr_t *src, ip_addr_t *dest,
+       u8_t proto, u16_t proto_len)
+{
+  u32_t acc;
+  u32_t addr;
+  struct pbuf *q;
+  u8_t swapped;
+
+  acc = 0;
+  swapped = 0;
+  /* iterate through all pbuf in chain */
+  for(q = p; q != NULL; q = q->next) {
+    LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): checksumming pbuf %p (has next %p) \n",
+      (void *)q, (void *)q->next));
+    acc += LWIP_CHKSUM(q->payload, q->len);
+    /*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): unwrapped lwip_chksum()=%"X32_F" \n", acc));*/
+    /* just executing this next line is probably faster that the if statement needed
+       to check whether we really need to execute it, and does no harm */
+    acc = FOLD_U32T(acc);
+    if (q->len % 2 != 0) {
+      swapped = 1 - swapped;
+      acc = SWAP_BYTES_IN_WORD(acc);
+    }
+    /*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): wrapped lwip_chksum()=%"X32_F" \n", acc));*/
+  }
+
+  if (swapped) {
+    acc = SWAP_BYTES_IN_WORD(acc);
+  }
+  addr = ip4_addr_get_u32(src);
+  acc += (addr & 0xffffUL);
+  acc += ((addr >> 16) & 0xffffUL);
+  addr = ip4_addr_get_u32(dest);
+  acc += (addr & 0xffffUL);
+  acc += ((addr >> 16) & 0xffffUL);
+  acc += (u32_t)htons((u16_t)proto);
+  acc += (u32_t)htons(proto_len);
+
+  /* Fold 32-bit sum to 16 bits
+     calling this twice is propably faster than if statements... */
+  acc = FOLD_U32T(acc);
+  acc = FOLD_U32T(acc);
+  LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): pbuf chain lwip_chksum()=%"X32_F"\n", acc));
+  return (u16_t)~(acc & 0xffffUL);
+}
+
+/* inet_chksum_pseudo:
+ *
+ * Calculates the pseudo Internet checksum used by TCP and UDP for a pbuf chain.
+ * IP addresses are expected to be in network byte order.
+ *
+ * @param p chain of pbufs over that a checksum should be calculated (ip data part)
+ * @param src source ip address (used for checksum of pseudo header)
+ * @param dst destination ip address (used for checksum of pseudo header)
+ * @param proto ip protocol (used for checksum of pseudo header)
+ * @param proto_len length of the ip data part (used for checksum of pseudo header)
+ * @return checksum (as u16_t) to be saved directly in the protocol header
+ */
+u16_t
+inet_chksum_pseudo_partial(struct pbuf *p,
+       ip_addr_t *src, ip_addr_t *dest,
+       u8_t proto, u16_t proto_len, u16_t chksum_len)
+{
+  u32_t acc;
+  u32_t addr;
+  struct pbuf *q;
+  u8_t swapped;
+  u16_t chklen;
+
+  acc = 0;
+  swapped = 0;
+  /* iterate through all pbuf in chain */
+  for(q = p; (q != NULL) && (chksum_len > 0); q = q->next) {
+    LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): checksumming pbuf %p (has next %p) \n",
+      (void *)q, (void *)q->next));
+    chklen = q->len;
+    if (chklen > chksum_len) {
+      chklen = chksum_len;
+    }
+    acc += LWIP_CHKSUM(q->payload, chklen);
+    chksum_len -= chklen;
+    LWIP_ASSERT("delete me", chksum_len < 0x7fff);
+    /*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): unwrapped lwip_chksum()=%"X32_F" \n", acc));*/
+    /* fold the upper bit down */
+    acc = FOLD_U32T(acc);
+    if (q->len % 2 != 0) {
+      swapped = 1 - swapped;
+      acc = SWAP_BYTES_IN_WORD(acc);
+    }
+    /*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): wrapped lwip_chksum()=%"X32_F" \n", acc));*/
+  }
+
+  if (swapped) {
+    acc = SWAP_BYTES_IN_WORD(acc);
+  }
+  addr = ip4_addr_get_u32(src);
+  acc += (addr & 0xffffUL);
+  acc += ((addr >> 16) & 0xffffUL);
+  addr = ip4_addr_get_u32(dest);
+  acc += (addr & 0xffffUL);
+  acc += ((addr >> 16) & 0xffffUL);
+  acc += (u32_t)htons((u16_t)proto);
+  acc += (u32_t)htons(proto_len);
+
+  /* Fold 32-bit sum to 16 bits
+     calling this twice is propably faster than if statements... */
+  acc = FOLD_U32T(acc);
+  acc = FOLD_U32T(acc);
+  LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): pbuf chain lwip_chksum()=%"X32_F"\n", acc));
+  return (u16_t)~(acc & 0xffffUL);
+}
+
+/* inet_chksum:
+ *
+ * Calculates the Internet checksum over a portion of memory. Used primarily for IP
+ * and ICMP.
+ *
+ * @param dataptr start of the buffer to calculate the checksum (no alignment needed)
+ * @param len length of the buffer to calculate the checksum
+ * @return checksum (as u16_t) to be saved directly in the protocol header
+ */
+
+u16_t
+inet_chksum(void *dataptr, u16_t len)
+{
+  return ~LWIP_CHKSUM(dataptr, len);
+}
+
+/**
+ * Calculate a checksum over a chain of pbufs (without pseudo-header, much like
+ * inet_chksum only pbufs are used).
+ *
+ * @param p pbuf chain over that the checksum should be calculated
+ * @return checksum (as u16_t) to be saved directly in the protocol header
+ */
+u16_t
+inet_chksum_pbuf(struct pbuf *p)
+{
+  u32_t acc;
+  struct pbuf *q;
+  u8_t swapped;
+
+  acc = 0;
+  swapped = 0;
+  for(q = p; q != NULL; q = q->next) {
+    acc += LWIP_CHKSUM(q->payload, q->len);
+    acc = FOLD_U32T(acc);
+    if (q->len % 2 != 0) {
+      swapped = 1 - swapped;
+      acc = SWAP_BYTES_IN_WORD(acc);
+    }
+  }
+
+  if (swapped) {
+    acc = SWAP_BYTES_IN_WORD(acc);
+  }
+  return (u16_t)~(acc & 0xffffUL);
+}
+
+/* These are some implementations for LWIP_CHKSUM_COPY, which copies data
+ * like MEMCPY but generates a checksum at the same time. Since this is a
+ * performance-sensitive function, you might want to create your own version
+ * in assembly targeted at your hardware by defining it in lwipopts.h:
+ *   #define LWIP_CHKSUM_COPY(dst, src, len) your_chksum_copy(dst, src, len)
+ */
+
+#if (LWIP_CHKSUM_COPY_ALGORITHM == 1) /* Version #1 */
+/** Safe but slow: first call MEMCPY, then call LWIP_CHKSUM.
+ * For architectures with big caches, data might still be in cache when
+ * generating the checksum after copying.
+ */
+u16_t
+lwip_chksum_copy(void *dst, const void *src, u16_t len)
+{
+  MEMCPY(dst, src, len);
+  return LWIP_CHKSUM(dst, len);
+}
+#endif /* (LWIP_CHKSUM_COPY_ALGORITHM == 1) */

src/lwip-1.4.1/src/core/ipv4/ip.c

@@ -0,0 +1,924 @@
+/**
+ * @file
+ * This is the IPv4 layer implementation for incoming and outgoing IP traffic.
+ * 
+ * @see ip_frag.c
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+#include "lwip/ip.h"
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/ip_frag.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/netif.h"
+#include "lwip/icmp.h"
+#include "lwip/igmp.h"
+#include "lwip/raw.h"
+#include "lwip/udp.h"
+#include "lwip/tcp_impl.h"
+#include "lwip/snmp.h"
+#include "lwip/dhcp.h"
+#include "lwip/autoip.h"
+#include "lwip/stats.h"
+#include "arch/perf.h"
+
+#include <string.h>
+
+/** Set this to 0 in the rare case of wanting to call an extra function to
+ * generate the IP checksum (in contrast to calculating it on-the-fly). */
+#ifndef LWIP_INLINE_IP_CHKSUM
+#define LWIP_INLINE_IP_CHKSUM   1
+#endif
+#if LWIP_INLINE_IP_CHKSUM && CHECKSUM_GEN_IP
+#define CHECKSUM_GEN_IP_INLINE  1
+#else
+#define CHECKSUM_GEN_IP_INLINE  0
+#endif
+
+#if LWIP_DHCP || defined(LWIP_IP_ACCEPT_UDP_PORT)
+#define IP_ACCEPT_LINK_LAYER_ADDRESSING 1
+
+/** Some defines for DHCP to let link-layer-addressed packets through while the
+ * netif is down.
+ * To use this in your own application/protocol, define LWIP_IP_ACCEPT_UDP_PORT
+ * to return 1 if the port is accepted and 0 if the port is not accepted.
+ */
+#if LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT)
+/* accept DHCP client port and custom port */
+#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) (((port) == PP_NTOHS(DHCP_CLIENT_PORT)) \
+         || (LWIP_IP_ACCEPT_UDP_PORT(port)))
+#elif defined(LWIP_IP_ACCEPT_UDP_PORT) /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
+/* accept custom port only */
+#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) (LWIP_IP_ACCEPT_UDP_PORT(port))
+#else /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
+/* accept DHCP client port only */
+#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) ((port) == PP_NTOHS(DHCP_CLIENT_PORT))
+#endif /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
+
+#else /* LWIP_DHCP */
+#define IP_ACCEPT_LINK_LAYER_ADDRESSING 0
+#endif /* LWIP_DHCP */
+
+/**
+ * The interface that provided the packet for the current callback
+ * invocation.
+ */
+struct netif *current_netif;
+
+/**
+ * Header of the input packet currently being processed.
+ */
+const struct ip_hdr *current_header;
+/** Source IP address of current_header */
+ip_addr_t current_iphdr_src;
+/** Destination IP address of current_header */
+ip_addr_t current_iphdr_dest;
+
+/** The IP header ID of the next outgoing IP packet */
+static u16_t ip_id;
+
+/**
+ * Finds the appropriate network interface for a given IP address. It
+ * searches the list of network interfaces linearly. A match is found
+ * if the masked IP address of the network interface equals the masked
+ * IP address given to the function.
+ *
+ * @param dest the destination IP address for which to find the route
+ * @return the netif on which to send to reach dest
+ */
+struct netif *
+ip_route(ip_addr_t *dest)
+{
+  struct netif *netif;
+
+#ifdef LWIP_HOOK_IP4_ROUTE
+  netif = LWIP_HOOK_IP4_ROUTE(dest);
+  if (netif != NULL) {
+    return netif;
+  }
+#endif
+
+  /* iterate through netifs */
+  for (netif = netif_list; netif != NULL; netif = netif->next) {
+    /* network mask matches? */
+    if (netif_is_up(netif)) {
+      if (ip_addr_netcmp(dest, &(netif->ip_addr), &(netif->netmask))) {
+        /* return netif on which to forward IP packet */
+        return netif;
+      }
+    }
+  }
+  if ((netif_default == NULL) || (!netif_is_up(netif_default))) {
+    LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_route: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+      ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
+    IP_STATS_INC(ip.rterr);
+    snmp_inc_ipoutnoroutes();
+    return NULL;
+  }
+  /* no matching netif found, use default netif */
+  return netif_default;
+}
+
+#if IP_FORWARD
+/**
+ * Determine whether an IP address is in a reserved set of addresses
+ * that may not be forwarded, or whether datagrams to that destination
+ * may be forwarded.
+ * @param p the packet to forward
+ * @param dest the destination IP address
+ * @return 1: can forward 0: discard
+ */
+static int
+ip_canforward(struct pbuf *p)
+{
+  u32_t addr = ip4_addr_get_u32(ip_current_dest_addr());
+
+  if (p->flags & PBUF_FLAG_LLBCAST) {
+    /* don't route link-layer broadcasts */
+    return 0;
+  }
+  if ((p->flags & PBUF_FLAG_LLMCAST) && !IP_MULTICAST(addr)) {
+    /* don't route link-layer multicasts unless the destination address is an IP
+       multicast address */
+    return 0;
+  }
+  if (IP_EXPERIMENTAL(addr)) {
+    return 0;
+  }
+  if (IP_CLASSA(addr)) {
+    u32_t net = addr & IP_CLASSA_NET;
+    if ((net == 0) || (net == (IP_LOOPBACKNET << IP_CLASSA_NSHIFT))) {
+      /* don't route loopback packets */
+      return 0;
+    }
+  }
+  return 1;
+}
+
+/**
+ * Forwards an IP packet. It finds an appropriate route for the
+ * packet, decrements the TTL value of the packet, adjusts the
+ * checksum and outputs the packet on the appropriate interface.
+ *
+ * @param p the packet to forward (p->payload points to IP header)
+ * @param iphdr the IP header of the input packet
+ * @param inp the netif on which this packet was received
+ */
+static void
+ip_forward(struct pbuf *p, struct ip_hdr *iphdr, struct netif *inp)
+{
+  struct netif *netif;
+
+  PERF_START;
+
+  if (!ip_canforward(p)) {
+    goto return_noroute;
+  }
+
+  /* RFC3927 2.7: do not forward link-local addresses */
+  if (ip_addr_islinklocal(&current_iphdr_dest)) {
+    LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not forwarding LLA %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+      ip4_addr1_16(&current_iphdr_dest), ip4_addr2_16(&current_iphdr_dest),
+      ip4_addr3_16(&current_iphdr_dest), ip4_addr4_16(&current_iphdr_dest)));
+    goto return_noroute;
+  }
+
+  /* Find network interface where to forward this IP packet to. */
+  netif = ip_route(&current_iphdr_dest);
+  if (netif == NULL) {
+    LWIP_DEBUGF(IP_DEBUG, ("ip_forward: no forwarding route for %"U16_F".%"U16_F".%"U16_F".%"U16_F" found\n",
+      ip4_addr1_16(&current_iphdr_dest), ip4_addr2_16(&current_iphdr_dest),
+      ip4_addr3_16(&current_iphdr_dest), ip4_addr4_16(&current_iphdr_dest)));
+    /* @todo: send ICMP_DUR_NET? */
+    goto return_noroute;
+  }
+#if !IP_FORWARD_ALLOW_TX_ON_RX_NETIF
+  /* Do not forward packets onto the same network interface on which
+   * they arrived. */
+  if (netif == inp) {
+    LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not bouncing packets back on incoming interface.\n"));
+    goto return_noroute;
+  }
+#endif /* IP_FORWARD_ALLOW_TX_ON_RX_NETIF */
+
+  /* decrement TTL */
+  IPH_TTL_SET(iphdr, IPH_TTL(iphdr) - 1);
+  /* send ICMP if TTL == 0 */
+  if (IPH_TTL(iphdr) == 0) {
+    snmp_inc_ipinhdrerrors();
+#if LWIP_ICMP
+    /* Don't send ICMP messages in response to ICMP messages */
+    if (IPH_PROTO(iphdr) != IP_PROTO_ICMP) {
+      icmp_time_exceeded(p, ICMP_TE_TTL);
+    }
+#endif /* LWIP_ICMP */
+    return;
+  }
+
+  /* Incrementally update the IP checksum. */
+  if (IPH_CHKSUM(iphdr) >= PP_HTONS(0xffffU - 0x100)) {
+    IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + PP_HTONS(0x100) + 1);
+  } else {
+    IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + PP_HTONS(0x100));
+  }
+
+  LWIP_DEBUGF(IP_DEBUG, ("ip_forward: forwarding packet to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+    ip4_addr1_16(&current_iphdr_dest), ip4_addr2_16(&current_iphdr_dest),
+    ip4_addr3_16(&current_iphdr_dest), ip4_addr4_16(&current_iphdr_dest)));
+
+  IP_STATS_INC(ip.fw);
+  IP_STATS_INC(ip.xmit);
+  snmp_inc_ipforwdatagrams();
+
+  PERF_STOP("ip_forward");
+  /* don't fragment if interface has mtu set to 0 [loopif] */
+  if (netif->mtu && (p->tot_len > netif->mtu)) {
+    if ((IPH_OFFSET(iphdr) & PP_NTOHS(IP_DF)) == 0) {
+#if IP_FRAG
+      ip_frag(p, netif, ip_current_dest_addr());
+#else /* IP_FRAG */
+      /* @todo: send ICMP Destination Unreacheable code 13 "Communication administratively prohibited"? */
+#endif /* IP_FRAG */
+    } else {
+      /* send ICMP Destination Unreacheable code 4: "Fragmentation Needed and DF Set" */
+      icmp_dest_unreach(p, ICMP_DUR_FRAG);
+    }
+    return;
+  }
+  /* transmit pbuf on chosen interface */
+  netif->output(netif, p, &current_iphdr_dest);
+  return;
+return_noroute:
+  snmp_inc_ipoutnoroutes();
+}
+#endif /* IP_FORWARD */
+
+/**
+ * This function is called by the network interface device driver when
+ * an IP packet is received. The function does the basic checks of the
+ * IP header such as packet size being at least larger than the header
+ * size etc. If the packet was not destined for us, the packet is
+ * forwarded (using ip_forward). The IP checksum is always checked.
+ *
+ * Finally, the packet is sent to the upper layer protocol input function.
+ * 
+ * @param p the received IP packet (p->payload points to IP header)
+ * @param inp the netif on which this packet was received
+ * @return ERR_OK if the packet was processed (could return ERR_* if it wasn't
+ *         processed, but currently always returns ERR_OK)
+ */
+err_t
+ip_input(struct pbuf *p, struct netif *inp)
+{
+  struct ip_hdr *iphdr;
+  struct netif *netif;
+  u16_t iphdr_hlen;
+  u16_t iphdr_len;
+#if IP_ACCEPT_LINK_LAYER_ADDRESSING
+  int check_ip_src=1;
+#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
+
+  IP_STATS_INC(ip.recv);
+  snmp_inc_ipinreceives();
+
+  /* identify the IP header */
+  iphdr = (struct ip_hdr *)p->payload;
+  if (IPH_V(iphdr) != 4) {
+    LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_WARNING, ("IP packet dropped due to bad version number %"U16_F"\n", IPH_V(iphdr)));
+    ip_debug_print(p);
+    pbuf_free(p);
+    IP_STATS_INC(ip.err);
+    IP_STATS_INC(ip.drop);
+    snmp_inc_ipinhdrerrors();
+    return ERR_OK;
+  }
+
+#ifdef LWIP_HOOK_IP4_INPUT
+  if (LWIP_HOOK_IP4_INPUT(p, inp)) {
+    /* the packet has been eaten */
+    return ERR_OK;
+  }
+#endif
+
+  /* obtain IP header length in number of 32-bit words */
+  iphdr_hlen = IPH_HL(iphdr);
+  /* calculate IP header length in bytes */
+  iphdr_hlen *= 4;
+  /* obtain ip length in bytes */
+  iphdr_len = ntohs(IPH_LEN(iphdr));
+
+  /* header length exceeds first pbuf length, or ip length exceeds total pbuf length? */
+  if ((iphdr_hlen > p->len) || (iphdr_len > p->tot_len)) {
+    if (iphdr_hlen > p->len) {
+      LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+        ("IP header (len %"U16_F") does not fit in first pbuf (len %"U16_F"), IP packet dropped.\n",
+        iphdr_hlen, p->len));
+    }
+    if (iphdr_len > p->tot_len) {
+      LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+        ("IP (len %"U16_F") is longer than pbuf (len %"U16_F"), IP packet dropped.\n",
+        iphdr_len, p->tot_len));
+    }
+    /* free (drop) packet pbufs */
+    pbuf_free(p);
+    IP_STATS_INC(ip.lenerr);
+    IP_STATS_INC(ip.drop);
+    snmp_inc_ipindiscards();
+    return ERR_OK;
+  }
+
+  /* verify checksum */
+#if CHECKSUM_CHECK_IP
+  if (inet_chksum(iphdr, iphdr_hlen) != 0) {
+
+    LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+      ("Checksum (0x%"X16_F") failed, IP packet dropped.\n", inet_chksum(iphdr, iphdr_hlen)));
+    ip_debug_print(p);
+    pbuf_free(p);
+    IP_STATS_INC(ip.chkerr);
+    IP_STATS_INC(ip.drop);
+    snmp_inc_ipinhdrerrors();
+    return ERR_OK;
+  }
+#endif
+
+  /* Trim pbuf. This should have been done at the netif layer,
+   * but we'll do it anyway just to be sure that its done. */
+  pbuf_realloc(p, iphdr_len);
+
+  /* copy IP addresses to aligned ip_addr_t */
+  ip_addr_copy(current_iphdr_dest, iphdr->dest);
+  ip_addr_copy(current_iphdr_src, iphdr->src);
+
+  /* match packet against an interface, i.e. is this packet for us? */
+#if LWIP_IGMP
+  if (ip_addr_ismulticast(&current_iphdr_dest)) {
+    if ((inp->flags & NETIF_FLAG_IGMP) && (igmp_lookfor_group(inp, &current_iphdr_dest))) {
+      netif = inp;
+    } else {
+      netif = NULL;
+    }
+  } else
+#endif /* LWIP_IGMP */
+  {
+    /* start trying with inp. if that's not acceptable, start walking the
+       list of configured netifs.
+       'first' is used as a boolean to mark whether we started walking the list */
+    int first = 1;
+    netif = inp;
+    do {
+      LWIP_DEBUGF(IP_DEBUG, ("ip_input: iphdr->dest 0x%"X32_F" netif->ip_addr 0x%"X32_F" (0x%"X32_F", 0x%"X32_F", 0x%"X32_F")\n",
+          ip4_addr_get_u32(&iphdr->dest), ip4_addr_get_u32(&netif->ip_addr),
+          ip4_addr_get_u32(&iphdr->dest) & ip4_addr_get_u32(&netif->netmask),
+          ip4_addr_get_u32(&netif->ip_addr) & ip4_addr_get_u32(&netif->netmask),
+          ip4_addr_get_u32(&iphdr->dest) & ~ip4_addr_get_u32(&netif->netmask)));
+
+      /* interface is up and configured? */
+      if ((netif_is_up(netif)) && (!ip_addr_isany(&(netif->ip_addr)))) {
+        /* unicast to this interface address? */
+        if (ip_addr_cmp(&current_iphdr_dest, &(netif->ip_addr)) ||
+            /* or broadcast on this interface network address? */
+            ip_addr_isbroadcast(&current_iphdr_dest, netif)) {
+          LWIP_DEBUGF(IP_DEBUG, ("ip_input: packet accepted on interface %c%c\n",
+              netif->name[0], netif->name[1]));
+          /* break out of for loop */
+          break;
+        }
+#if LWIP_AUTOIP
+        /* connections to link-local addresses must persist after changing
+           the netif's address (RFC3927 ch. 1.9) */
+        if ((netif->autoip != NULL) &&
+            ip_addr_cmp(&current_iphdr_dest, &(netif->autoip->llipaddr))) {
+          LWIP_DEBUGF(IP_DEBUG, ("ip_input: LLA packet accepted on interface %c%c\n",
+              netif->name[0], netif->name[1]));
+          /* break out of for loop */
+          break;
+        }
+#endif /* LWIP_AUTOIP */
+      }
+      if (first) {
+        first = 0;
+        netif = netif_list;
+      } else {
+        netif = netif->next;
+      }
+      if (netif == inp) {
+        netif = netif->next;
+      }
+    } while(netif != NULL);
+  }
+
+#if IP_ACCEPT_LINK_LAYER_ADDRESSING
+  /* Pass DHCP messages regardless of destination address. DHCP traffic is addressed
+   * using link layer addressing (such as Ethernet MAC) so we must not filter on IP.
+   * According to RFC 1542 section 3.1.1, referred by RFC 2131).
+   *
+   * If you want to accept private broadcast communication while a netif is down,
+   * define LWIP_IP_ACCEPT_UDP_PORT(dst_port), e.g.:
+   *
+   * #define LWIP_IP_ACCEPT_UDP_PORT(dst_port) ((dst_port) == PP_NTOHS(12345))
+   */
+  if (netif == NULL) {
+    /* remote port is DHCP server? */
+    if (IPH_PROTO(iphdr) == IP_PROTO_UDP) {
+      struct udp_hdr *udphdr = (struct udp_hdr *)((u8_t *)iphdr + iphdr_hlen);
+      LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: UDP packet to DHCP client port %"U16_F"\n",
+        ntohs(udphdr->dest)));
+      if (IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(udphdr->dest)) {
+        LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: DHCP packet accepted.\n"));
+        netif = inp;
+        check_ip_src = 0;
+      }
+    }
+  }
+#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
+
+  /* broadcast or multicast packet source address? Compliant with RFC 1122: 3.2.1.3 */
+#if IP_ACCEPT_LINK_LAYER_ADDRESSING
+  /* DHCP servers need 0.0.0.0 to be allowed as source address (RFC 1.1.2.2: 3.2.1.3/a) */
+  if (check_ip_src && !ip_addr_isany(&current_iphdr_src))
+#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
+  {  if ((ip_addr_isbroadcast(&current_iphdr_src, inp)) ||
+         (ip_addr_ismulticast(&current_iphdr_src))) {
+      /* packet source is not valid */
+      LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, ("ip_input: packet source is not valid.\n"));
+      /* free (drop) packet pbufs */
+      pbuf_free(p);
+      IP_STATS_INC(ip.drop);
+      snmp_inc_ipinaddrerrors();
+      snmp_inc_ipindiscards();
+      return ERR_OK;
+    }
+  }
+
+  /* packet not for us? */
+  if (netif == NULL) {
+    /* packet not for us, route or discard */
+    LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: packet not for us.\n"));
+#if IP_FORWARD
+    /* non-broadcast packet? */
+    if (!ip_addr_isbroadcast(&current_iphdr_dest, inp)) {
+      /* try to forward IP packet on (other) interfaces */
+      ip_forward(p, iphdr, inp);
+    } else
+#endif /* IP_FORWARD */
+    {
+      snmp_inc_ipinaddrerrors();
+      snmp_inc_ipindiscards();
+    }
+    pbuf_free(p);
+    return ERR_OK;
+  }
+  /* packet consists of multiple fragments? */
+  if ((IPH_OFFSET(iphdr) & PP_HTONS(IP_OFFMASK | IP_MF)) != 0) {
+#if IP_REASSEMBLY /* packet fragment reassembly code present? */
+    LWIP_DEBUGF(IP_DEBUG, ("IP packet is a fragment (id=0x%04"X16_F" tot_len=%"U16_F" len=%"U16_F" MF=%"U16_F" offset=%"U16_F"), calling ip_reass()\n",
+      ntohs(IPH_ID(iphdr)), p->tot_len, ntohs(IPH_LEN(iphdr)), !!(IPH_OFFSET(iphdr) & PP_HTONS(IP_MF)), (ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK)*8));
+    /* reassemble the packet*/
+    p = ip_reass(p);
+    /* packet not fully reassembled yet? */
+    if (p == NULL) {
+      return ERR_OK;
+    }
+    iphdr = (struct ip_hdr *)p->payload;
+#else /* IP_REASSEMBLY == 0, no packet fragment reassembly code present */
+    pbuf_free(p);
+    LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since it was fragmented (0x%"X16_F") (while IP_REASSEMBLY == 0).\n",
+      ntohs(IPH_OFFSET(iphdr))));
+    IP_STATS_INC(ip.opterr);
+    IP_STATS_INC(ip.drop);
+    /* unsupported protocol feature */
+    snmp_inc_ipinunknownprotos();
+    return ERR_OK;
+#endif /* IP_REASSEMBLY */
+  }
+
+#if IP_OPTIONS_ALLOWED == 0 /* no support for IP options in the IP header? */
+
+#if LWIP_IGMP
+  /* there is an extra "router alert" option in IGMP messages which we allow for but do not police */
+  if((iphdr_hlen > IP_HLEN) &&  (IPH_PROTO(iphdr) != IP_PROTO_IGMP)) {
+#else
+  if (iphdr_hlen > IP_HLEN) {
+#endif /* LWIP_IGMP */
+    LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since there were IP options (while IP_OPTIONS_ALLOWED == 0).\n"));
+    pbuf_free(p);
+    IP_STATS_INC(ip.opterr);
+    IP_STATS_INC(ip.drop);
+    /* unsupported protocol feature */
+    snmp_inc_ipinunknownprotos();
+    return ERR_OK;
+  }
+#endif /* IP_OPTIONS_ALLOWED == 0 */
+
+  /* send to upper layers */
+  LWIP_DEBUGF(IP_DEBUG, ("ip_input: \n"));
+  ip_debug_print(p);
+  LWIP_DEBUGF(IP_DEBUG, ("ip_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len));
+
+  current_netif = inp;
+  current_header = iphdr;
+
+#if LWIP_RAW
+  /* raw input did not eat the packet? */
+  if (raw_input(p, inp) == 0)
+#endif /* LWIP_RAW */
+  {
+    switch (IPH_PROTO(iphdr)) {
+#if LWIP_UDP
+    case IP_PROTO_UDP:
+#if LWIP_UDPLITE
+    case IP_PROTO_UDPLITE:
+#endif /* LWIP_UDPLITE */
+      snmp_inc_ipindelivers();
+      udp_input(p, inp);
+      break;
+#endif /* LWIP_UDP */
+#if LWIP_TCP
+    case IP_PROTO_TCP:
+      snmp_inc_ipindelivers();
+      tcp_input(p, inp);
+      break;
+#endif /* LWIP_TCP */
+#if LWIP_ICMP
+    case IP_PROTO_ICMP:
+      snmp_inc_ipindelivers();
+      icmp_input(p, inp);
+      break;
+#endif /* LWIP_ICMP */
+#if LWIP_IGMP
+    case IP_PROTO_IGMP:
+      igmp_input(p, inp, &current_iphdr_dest);
+      break;
+#endif /* LWIP_IGMP */
+    default:
+#if LWIP_ICMP
+      /* send ICMP destination protocol unreachable unless is was a broadcast */
+      if (!ip_addr_isbroadcast(&current_iphdr_dest, inp) &&
+          !ip_addr_ismulticast(&current_iphdr_dest)) {
+        p->payload = iphdr;
+        icmp_dest_unreach(p, ICMP_DUR_PROTO);
+      }
+#endif /* LWIP_ICMP */
+      pbuf_free(p);
+
+      LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("Unsupported transport protocol %"U16_F"\n", IPH_PROTO(iphdr)));
+
+      IP_STATS_INC(ip.proterr);
+      IP_STATS_INC(ip.drop);
+      snmp_inc_ipinunknownprotos();
+    }
+  }
+
+  current_netif = NULL;
+  current_header = NULL;
+  ip_addr_set_any(&current_iphdr_src);
+  ip_addr_set_any(&current_iphdr_dest);
+
+  return ERR_OK;
+}
+
+/**
+ * Sends an IP packet on a network interface. This function constructs
+ * the IP header and calculates the IP header checksum. If the source
+ * IP address is NULL, the IP address of the outgoing network
+ * interface is filled in as source address.
+ * If the destination IP address is IP_HDRINCL, p is assumed to already
+ * include an IP header and p->payload points to it instead of the data.
+ *
+ * @param p the packet to send (p->payload points to the data, e.g. next
+            protocol header; if dest == IP_HDRINCL, p already includes an IP
+            header and p->payload points to that IP header)
+ * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
+ *         IP  address of the netif used to send is used as source address)
+ * @param dest the destination IP address to send the packet to
+ * @param ttl the TTL value to be set in the IP header
+ * @param tos the TOS value to be set in the IP header
+ * @param proto the PROTOCOL to be set in the IP header
+ * @param netif the netif on which to send this packet
+ * @return ERR_OK if the packet was sent OK
+ *         ERR_BUF if p doesn't have enough space for IP/LINK headers
+ *         returns errors returned by netif->output
+ *
+ * @note ip_id: RFC791 "some host may be able to simply use
+ *  unique identifiers independent of destination"
+ */
+err_t
+ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+             u8_t ttl, u8_t tos,
+             u8_t proto, struct netif *netif)
+{
+#if IP_OPTIONS_SEND
+  return ip_output_if_opt(p, src, dest, ttl, tos, proto, netif, NULL, 0);
+}
+
+/**
+ * Same as ip_output_if() but with the possibility to include IP options:
+ *
+ * @ param ip_options pointer to the IP options, copied into the IP header
+ * @ param optlen length of ip_options
+ */
+err_t ip_output_if_opt(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+       u8_t ttl, u8_t tos, u8_t proto, struct netif *netif, void *ip_options,
+       u16_t optlen)
+{
+#endif /* IP_OPTIONS_SEND */
+  struct ip_hdr *iphdr;
+  ip_addr_t dest_addr;
+#if CHECKSUM_GEN_IP_INLINE
+  u32_t chk_sum = 0;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+
+  /* pbufs passed to IP must have a ref-count of 1 as their payload pointer
+     gets altered as the packet is passed down the stack */
+  LWIP_ASSERT("p->ref == 1", p->ref == 1);
+
+  snmp_inc_ipoutrequests();
+
+  /* Should the IP header be generated or is it already included in p? */
+  if (dest != IP_HDRINCL) {
+    u16_t ip_hlen = IP_HLEN;
+#if IP_OPTIONS_SEND
+    u16_t optlen_aligned = 0;
+    if (optlen != 0) {
+#if CHECKSUM_GEN_IP_INLINE
+      int i;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+      /* round up to a multiple of 4 */
+      optlen_aligned = ((optlen + 3) & ~3);
+      ip_hlen += optlen_aligned;
+      /* First write in the IP options */
+      if (pbuf_header(p, optlen_aligned)) {
+        LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output_if_opt: not enough room for IP options in pbuf\n"));
+        IP_STATS_INC(ip.err);
+        snmp_inc_ipoutdiscards();
+        return ERR_BUF;
+      }
+      MEMCPY(p->payload, ip_options, optlen);
+      if (optlen < optlen_aligned) {
+        /* zero the remaining bytes */
+        memset(((char*)p->payload) + optlen, 0, optlen_aligned - optlen);
+      }
+#if CHECKSUM_GEN_IP_INLINE
+      for (i = 0; i < optlen_aligned/2; i++) {
+        chk_sum += ((u16_t*)p->payload)[i];
+      }
+#endif /* CHECKSUM_GEN_IP_INLINE */
+    }
+#endif /* IP_OPTIONS_SEND */
+    /* generate IP header */
+    if (pbuf_header(p, IP_HLEN)) {
+      LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output: not enough room for IP header in pbuf\n"));
+
+      IP_STATS_INC(ip.err);
+      snmp_inc_ipoutdiscards();
+      return ERR_BUF;
+    }
+
+    iphdr = (struct ip_hdr *)p->payload;
+    LWIP_ASSERT("check that first pbuf can hold struct ip_hdr",
+               (p->len >= sizeof(struct ip_hdr)));
+
+    IPH_TTL_SET(iphdr, ttl);
+    IPH_PROTO_SET(iphdr, proto);
+#if CHECKSUM_GEN_IP_INLINE
+    chk_sum += LWIP_MAKE_U16(proto, ttl);
+#endif /* CHECKSUM_GEN_IP_INLINE */
+
+    /* dest cannot be NULL here */
+    ip_addr_copy(iphdr->dest, *dest);
+#if CHECKSUM_GEN_IP_INLINE
+    chk_sum += ip4_addr_get_u32(&iphdr->dest) & 0xFFFF;
+    chk_sum += ip4_addr_get_u32(&iphdr->dest) >> 16;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+
+    IPH_VHL_SET(iphdr, 4, ip_hlen / 4);
+    IPH_TOS_SET(iphdr, tos);
+#if CHECKSUM_GEN_IP_INLINE
+    chk_sum += LWIP_MAKE_U16(tos, iphdr->_v_hl);
+#endif /* CHECKSUM_GEN_IP_INLINE */
+    IPH_LEN_SET(iphdr, htons(p->tot_len));
+#if CHECKSUM_GEN_IP_INLINE
+    chk_sum += iphdr->_len;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+    IPH_OFFSET_SET(iphdr, 0);
+    IPH_ID_SET(iphdr, htons(ip_id));
+#if CHECKSUM_GEN_IP_INLINE
+    chk_sum += iphdr->_id;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+    ++ip_id;
+
+    if (ip_addr_isany(src)) {
+      ip_addr_copy(iphdr->src, netif->ip_addr);
+    } else {
+      /* src cannot be NULL here */
+      ip_addr_copy(iphdr->src, *src);
+    }
+
+#if CHECKSUM_GEN_IP_INLINE
+    chk_sum += ip4_addr_get_u32(&iphdr->src) & 0xFFFF;
+    chk_sum += ip4_addr_get_u32(&iphdr->src) >> 16;
+    chk_sum = (chk_sum >> 16) + (chk_sum & 0xFFFF);
+    chk_sum = (chk_sum >> 16) + chk_sum;
+    chk_sum = ~chk_sum;
+    iphdr->_chksum = chk_sum; /* network order */
+#else /* CHECKSUM_GEN_IP_INLINE */
+    IPH_CHKSUM_SET(iphdr, 0);
+#if CHECKSUM_GEN_IP
+    IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, ip_hlen));
+#endif
+#endif /* CHECKSUM_GEN_IP_INLINE */
+  } else {
+    /* IP header already included in p */
+    iphdr = (struct ip_hdr *)p->payload;
+    ip_addr_copy(dest_addr, iphdr->dest);
+    dest = &dest_addr;
+  }
+
+  IP_STATS_INC(ip.xmit);
+
+  LWIP_DEBUGF(IP_DEBUG, ("ip_output_if: %c%c%"U16_F"\n", netif->name[0], netif->name[1], netif->num));
+  ip_debug_print(p);
+
+#if ENABLE_LOOPBACK
+  if (ip_addr_cmp(dest, &netif->ip_addr)) {
+    /* Packet to self, enqueue it for loopback */
+    LWIP_DEBUGF(IP_DEBUG, ("netif_loop_output()"));
+    return netif_loop_output(netif, p, dest);
+  }
+#if LWIP_IGMP
+  if ((p->flags & PBUF_FLAG_MCASTLOOP) != 0) {
+    netif_loop_output(netif, p, dest);
+  }
+#endif /* LWIP_IGMP */
+#endif /* ENABLE_LOOPBACK */
+#if IP_FRAG
+  /* don't fragment if interface has mtu set to 0 [loopif] */
+  if (netif->mtu && (p->tot_len > netif->mtu)) {
+    return ip_frag(p, netif, dest);
+  }
+#endif /* IP_FRAG */
+
+  LWIP_DEBUGF(IP_DEBUG, ("netif->output()"));
+  return netif->output(netif, p, dest);
+}
+
+/**
+ * Simple interface to ip_output_if. It finds the outgoing network
+ * interface and calls upon ip_output_if to do the actual work.
+ *
+ * @param p the packet to send (p->payload points to the data, e.g. next
+            protocol header; if dest == IP_HDRINCL, p already includes an IP
+            header and p->payload points to that IP header)
+ * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
+ *         IP  address of the netif used to send is used as source address)
+ * @param dest the destination IP address to send the packet to
+ * @param ttl the TTL value to be set in the IP header
+ * @param tos the TOS value to be set in the IP header
+ * @param proto the PROTOCOL to be set in the IP header
+ *
+ * @return ERR_RTE if no route is found
+ *         see ip_output_if() for more return values
+ */
+err_t
+ip_output(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+          u8_t ttl, u8_t tos, u8_t proto)
+{
+  struct netif *netif;
+
+  /* pbufs passed to IP must have a ref-count of 1 as their payload pointer
+     gets altered as the packet is passed down the stack */
+  LWIP_ASSERT("p->ref == 1", p->ref == 1);
+
+  if ((netif = ip_route(dest)) == NULL) {
+    LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+      ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
+    IP_STATS_INC(ip.rterr);
+    return ERR_RTE;
+  }
+
+  return ip_output_if(p, src, dest, ttl, tos, proto, netif);
+}
+
+#if LWIP_NETIF_HWADDRHINT
+/** Like ip_output, but takes and addr_hint pointer that is passed on to netif->addr_hint
+ *  before calling ip_output_if.
+ *
+ * @param p the packet to send (p->payload points to the data, e.g. next
+            protocol header; if dest == IP_HDRINCL, p already includes an IP
+            header and p->payload points to that IP header)
+ * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
+ *         IP  address of the netif used to send is used as source address)
+ * @param dest the destination IP address to send the packet to
+ * @param ttl the TTL value to be set in the IP header
+ * @param tos the TOS value to be set in the IP header
+ * @param proto the PROTOCOL to be set in the IP header
+ * @param addr_hint address hint pointer set to netif->addr_hint before
+ *        calling ip_output_if()
+ *
+ * @return ERR_RTE if no route is found
+ *         see ip_output_if() for more return values
+ */
+err_t
+ip_output_hinted(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+          u8_t ttl, u8_t tos, u8_t proto, u8_t *addr_hint)
+{
+  struct netif *netif;
+  err_t err;
+
+  /* pbufs passed to IP must have a ref-count of 1 as their payload pointer
+     gets altered as the packet is passed down the stack */
+  LWIP_ASSERT("p->ref == 1", p->ref == 1);
+
+  if ((netif = ip_route(dest)) == NULL) {
+    LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+      ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
+    IP_STATS_INC(ip.rterr);
+    return ERR_RTE;
+  }
+
+  NETIF_SET_HWADDRHINT(netif, addr_hint);
+  err = ip_output_if(p, src, dest, ttl, tos, proto, netif);
+  NETIF_SET_HWADDRHINT(netif, NULL);
+
+  return err;
+}
+#endif /* LWIP_NETIF_HWADDRHINT*/
+
+#if IP_DEBUG
+/* Print an IP header by using LWIP_DEBUGF
+ * @param p an IP packet, p->payload pointing to the IP header
+ */
+void
+ip_debug_print(struct pbuf *p)
+{
+  struct ip_hdr *iphdr = (struct ip_hdr *)p->payload;
+
+  LWIP_DEBUGF(IP_DEBUG, ("IP header:\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|%2"S16_F" |%2"S16_F" |  0x%02"X16_F" |     %5"U16_F"     | (v, hl, tos, len)\n",
+                    IPH_V(iphdr),
+                    IPH_HL(iphdr),
+                    IPH_TOS(iphdr),
+                    ntohs(IPH_LEN(iphdr))));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|    %5"U16_F"      |%"U16_F"%"U16_F"%"U16_F"|    %4"U16_F"   | (id, flags, offset)\n",
+                    ntohs(IPH_ID(iphdr)),
+                    ntohs(IPH_OFFSET(iphdr)) >> 15 & 1,
+                    ntohs(IPH_OFFSET(iphdr)) >> 14 & 1,
+                    ntohs(IPH_OFFSET(iphdr)) >> 13 & 1,
+                    ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|  %3"U16_F"  |  %3"U16_F"  |    0x%04"X16_F"     | (ttl, proto, chksum)\n",
+                    IPH_TTL(iphdr),
+                    IPH_PROTO(iphdr),
+                    ntohs(IPH_CHKSUM(iphdr))));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|  %3"U16_F"  |  %3"U16_F"  |  %3"U16_F"  |  %3"U16_F"  | (src)\n",
+                    ip4_addr1_16(&iphdr->src),
+                    ip4_addr2_16(&iphdr->src),
+                    ip4_addr3_16(&iphdr->src),
+                    ip4_addr4_16(&iphdr->src)));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|  %3"U16_F"  |  %3"U16_F"  |  %3"U16_F"  |  %3"U16_F"  | (dest)\n",
+                    ip4_addr1_16(&iphdr->dest),
+                    ip4_addr2_16(&iphdr->dest),
+                    ip4_addr3_16(&iphdr->dest),
+                    ip4_addr4_16(&iphdr->dest)));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+}
+#endif /* IP_DEBUG */

src/lwip-1.4.1/src/core/ipv4/ip_addr.c

@@ -0,0 +1,312 @@
+/**
+ * @file
+ * This is the IPv4 address tools implementation.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+
+/* used by IP_ADDR_ANY and IP_ADDR_BROADCAST in ip_addr.h */
+const ip_addr_t ip_addr_any = { IPADDR_ANY };
+const ip_addr_t ip_addr_broadcast = { IPADDR_BROADCAST };
+
+/**
+ * Determine if an address is a broadcast address on a network interface 
+ * 
+ * @param addr address to be checked
+ * @param netif the network interface against which the address is checked
+ * @return returns non-zero if the address is a broadcast address
+ */
+u8_t
+ip4_addr_isbroadcast(u32_t addr, const struct netif *netif)
+{
+  ip_addr_t ipaddr;
+  ip4_addr_set_u32(&ipaddr, addr);
+
+  /* all ones (broadcast) or all zeroes (old skool broadcast) */
+  if ((~addr == IPADDR_ANY) ||
+      (addr == IPADDR_ANY)) {
+    return 1;
+  /* no broadcast support on this network interface? */
+  } else if ((netif->flags & NETIF_FLAG_BROADCAST) == 0) {
+    /* the given address cannot be a broadcast address
+     * nor can we check against any broadcast addresses */
+    return 0;
+  /* address matches network interface address exactly? => no broadcast */
+  } else if (addr == ip4_addr_get_u32(&netif->ip_addr)) {
+    return 0;
+  /*  on the same (sub) network... */
+  } else if (ip_addr_netcmp(&ipaddr, &(netif->ip_addr), &(netif->netmask))
+         /* ...and host identifier bits are all ones? =>... */
+          && ((addr & ~ip4_addr_get_u32(&netif->netmask)) ==
+           (IPADDR_BROADCAST & ~ip4_addr_get_u32(&netif->netmask)))) {
+    /* => network broadcast address */
+    return 1;
+  } else {
+    return 0;
+  }
+}
+
+/** Checks if a netmask is valid (starting with ones, then only zeros)
+ *
+ * @param netmask the IPv4 netmask to check (in network byte order!)
+ * @return 1 if the netmask is valid, 0 if it is not
+ */
+u8_t
+ip4_addr_netmask_valid(u32_t netmask)
+{
+  u32_t mask;
+  u32_t nm_hostorder = lwip_htonl(netmask);
+
+  /* first, check for the first zero */
+  for (mask = 1UL << 31 ; mask != 0; mask >>= 1) {
+    if ((nm_hostorder & mask) == 0) {
+      break;
+    }
+  }
+  /* then check that there is no one */
+  for (; mask != 0; mask >>= 1) {
+    if ((nm_hostorder & mask) != 0) {
+      /* there is a one after the first zero -> invalid */
+      return 0;
+    }
+  }
+  /* no one after the first zero -> valid */
+  return 1;
+}
+
+/* Here for now until needed in other places in lwIP */
+#ifndef isprint
+#define in_range(c, lo, up)  ((u8_t)c >= lo && (u8_t)c <= up)
+#define isprint(c)           in_range(c, 0x20, 0x7f)
+#define isdigit(c)           in_range(c, '0', '9')
+#define isxdigit(c)          (isdigit(c) || in_range(c, 'a', 'f') || in_range(c, 'A', 'F'))
+#define islower(c)           in_range(c, 'a', 'z')
+#define isspace(c)           (c == ' ' || c == '\f' || c == '\n' || c == '\r' || c == '\t' || c == '\v')
+#endif
+
+/**
+ * Ascii internet address interpretation routine.
+ * The value returned is in network order.
+ *
+ * @param cp IP address in ascii represenation (e.g. "127.0.0.1")
+ * @return ip address in network order
+ */
+u32_t
+ipaddr_addr(const char *cp)
+{
+  ip_addr_t val;
+
+  if (ipaddr_aton(cp, &val)) {
+    return ip4_addr_get_u32(&val);
+  }
+  return (IPADDR_NONE);
+}
+
+/**
+ * Check whether "cp" is a valid ascii representation
+ * of an Internet address and convert to a binary address.
+ * Returns 1 if the address is valid, 0 if not.
+ * This replaces inet_addr, the return value from which
+ * cannot distinguish between failure and a local broadcast address.
+ *
+ * @param cp IP address in ascii represenation (e.g. "127.0.0.1")
+ * @param addr pointer to which to save the ip address in network order
+ * @return 1 if cp could be converted to addr, 0 on failure
+ */
+int
+ipaddr_aton(const char *cp, ip_addr_t *addr)
+{
+  u32_t val;
+  u8_t base;
+  char c;
+  u32_t parts[4];
+  u32_t *pp = parts;
+
+  c = *cp;
+  for (;;) {
+    /*
+     * Collect number up to ``.''.
+     * Values are specified as for C:
+     * 0x=hex, 0=octal, 1-9=decimal.
+     */
+    if (!isdigit(c))
+      return (0);
+    val = 0;
+    base = 10;
+    if (c == '0') {
+      c = *++cp;
+      if (c == 'x' || c == 'X') {
+        base = 16;
+        c = *++cp;
+      } else
+        base = 8;
+    }
+    for (;;) {
+      if (isdigit(c)) {
+        val = (val * base) + (int)(c - '0');
+        c = *++cp;
+      } else if (base == 16 && isxdigit(c)) {
+        val = (val << 4) | (int)(c + 10 - (islower(c) ? 'a' : 'A'));
+        c = *++cp;
+      } else
+        break;
+    }
+    if (c == '.') {
+      /*
+       * Internet format:
+       *  a.b.c.d
+       *  a.b.c   (with c treated as 16 bits)
+       *  a.b (with b treated as 24 bits)
+       */
+      if (pp >= parts + 3) {
+        return (0);
+      }
+      *pp++ = val;
+      c = *++cp;
+    } else
+      break;
+  }
+  /*
+   * Check for trailing characters.
+   */
+  if (c != '\0' && !isspace(c)) {
+    return (0);
+  }
+  /*
+   * Concoct the address according to
+   * the number of parts specified.
+   */
+  switch (pp - parts + 1) {
+
+  case 0:
+    return (0);       /* initial nondigit */
+
+  case 1:             /* a -- 32 bits */
+    break;
+
+  case 2:             /* a.b -- 8.24 bits */
+    if (val > 0xffffffUL) {
+      return (0);
+    }
+    val |= parts[0] << 24;
+    break;
+
+  case 3:             /* a.b.c -- 8.8.16 bits */
+    if (val > 0xffff) {
+      return (0);
+    }
+    val |= (parts[0] << 24) | (parts[1] << 16);
+    break;
+
+  case 4:             /* a.b.c.d -- 8.8.8.8 bits */
+    if (val > 0xff) {
+      return (0);
+    }
+    val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
+    break;
+  default:
+    LWIP_ASSERT("unhandled", 0);
+    break;
+  }
+  if (addr) {
+    ip4_addr_set_u32(addr, htonl(val));
+  }
+  return (1);
+}
+
+/**
+ * Convert numeric IP address into decimal dotted ASCII representation.
+ * returns ptr to static buffer; not reentrant!
+ *
+ * @param addr ip address in network order to convert
+ * @return pointer to a global static (!) buffer that holds the ASCII
+ *         represenation of addr
+ */
+char *
+ipaddr_ntoa(const ip_addr_t *addr)
+{
+  static char str[16];
+  return ipaddr_ntoa_r(addr, str, 16);
+}
+
+/**
+ * Same as ipaddr_ntoa, but reentrant since a user-supplied buffer is used.
+ *
+ * @param addr ip address in network order to convert
+ * @param buf target buffer where the string is stored
+ * @param buflen length of buf
+ * @return either pointer to buf which now holds the ASCII
+ *         representation of addr or NULL if buf was too small
+ */
+char *ipaddr_ntoa_r(const ip_addr_t *addr, char *buf, int buflen)
+{
+  u32_t s_addr;
+  char inv[3];
+  char *rp;
+  u8_t *ap;
+  u8_t rem;
+  u8_t n;
+  u8_t i;
+  int len = 0;
+
+  s_addr = ip4_addr_get_u32(addr);
+
+  rp = buf;
+  ap = (u8_t *)&s_addr;
+  for(n = 0; n < 4; n++) {
+    i = 0;
+    do {
+      rem = *ap % (u8_t)10;
+      *ap /= (u8_t)10;
+      inv[i++] = '0' + rem;
+    } while(*ap);
+    while(i--) {
+      if (len++ >= buflen) {
+        return NULL;
+      }
+      *rp++ = inv[i];
+    }
+    if (len++ >= buflen) {
+      return NULL;
+    }
+    *rp++ = '.';
+    ap++;
+  }
+  *--rp = 0;
+  return buf;
+}

src/lwip-1.4.1/src/core/ipv4/ip_frag.c

@@ -0,0 +1,863 @@
+/**
+ * @file
+ * This is the IPv4 packet segmentation and reassembly implementation.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Jani Monoses <jani@iv.ro> 
+ *         Simon Goldschmidt
+ * original reassembly code by Adam Dunkels <adam@sics.se>
+ * 
+ */
+
+#include "lwip/opt.h"
+#include "lwip/ip_frag.h"
+#include "lwip/def.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/netif.h"
+#include "lwip/snmp.h"
+#include "lwip/stats.h"
+#include "lwip/icmp.h"
+
+#include <string.h>
+
+#if IP_REASSEMBLY
+/**
+ * The IP reassembly code currently has the following limitations:
+ * - IP header options are not supported
+ * - fragments must not overlap (e.g. due to different routes),
+ *   currently, overlapping or duplicate fragments are thrown away
+ *   if IP_REASS_CHECK_OVERLAP=1 (the default)!
+ *
+ * @todo: work with IP header options
+ */
+
+/** Setting this to 0, you can turn off checking the fragments for overlapping
+ * regions. The code gets a little smaller. Only use this if you know that
+ * overlapping won't occur on your network! */
+#ifndef IP_REASS_CHECK_OVERLAP
+#define IP_REASS_CHECK_OVERLAP 1
+#endif /* IP_REASS_CHECK_OVERLAP */
+
+/** Set to 0 to prevent freeing the oldest datagram when the reassembly buffer is
+ * full (IP_REASS_MAX_PBUFS pbufs are enqueued). The code gets a little smaller.
+ * Datagrams will be freed by timeout only. Especially useful when MEMP_NUM_REASSDATA
+ * is set to 1, so one datagram can be reassembled at a time, only. */
+#ifndef IP_REASS_FREE_OLDEST
+#define IP_REASS_FREE_OLDEST 1
+#endif /* IP_REASS_FREE_OLDEST */
+
+#define IP_REASS_FLAG_LASTFRAG 0x01
+
+/** This is a helper struct which holds the starting
+ * offset and the ending offset of this fragment to
+ * easily chain the fragments.
+ * It has the same packing requirements as the IP header, since it replaces
+ * the IP header in memory in incoming fragments (after copying it) to keep
+ * track of the various fragments. (-> If the IP header doesn't need packing,
+ * this struct doesn't need packing, too.)
+ */
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/bpstruct.h"
+#endif
+PACK_STRUCT_BEGIN
+struct ip_reass_helper {
+  PACK_STRUCT_FIELD(struct pbuf *next_pbuf);
+  PACK_STRUCT_FIELD(u16_t start);
+  PACK_STRUCT_FIELD(u16_t end);
+} PACK_STRUCT_STRUCT;
+PACK_STRUCT_END
+#ifdef PACK_STRUCT_USE_INCLUDES
+#  include "arch/epstruct.h"
+#endif
+
+#define IP_ADDRESSES_AND_ID_MATCH(iphdrA, iphdrB)  \
+  (ip_addr_cmp(&(iphdrA)->src, &(iphdrB)->src) && \
+   ip_addr_cmp(&(iphdrA)->dest, &(iphdrB)->dest) && \
+   IPH_ID(iphdrA) == IPH_ID(iphdrB)) ? 1 : 0
+
+/* global variables */
+static struct ip_reassdata *reassdatagrams;
+static u16_t ip_reass_pbufcount;
+
+/* function prototypes */
+static void ip_reass_dequeue_datagram(struct ip_reassdata *ipr, struct ip_reassdata *prev);
+static int ip_reass_free_complete_datagram(struct ip_reassdata *ipr, struct ip_reassdata *prev);
+
+/**
+ * Reassembly timer base function
+ * for both NO_SYS == 0 and 1 (!).
+ *
+ * Should be called every 1000 msec (defined by IP_TMR_INTERVAL).
+ */
+void
+ip_reass_tmr(void)
+{
+  struct ip_reassdata *r, *prev = NULL;
+
+  r = reassdatagrams;
+  while (r != NULL) {
+    /* Decrement the timer. Once it reaches 0,
+     * clean up the incomplete fragment assembly */
+    if (r->timer > 0) {
+      r->timer--;
+      LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_reass_tmr: timer dec %"U16_F"\n",(u16_t)r->timer));
+      prev = r;
+      r = r->next;
+    } else {
+      /* reassembly timed out */
+      struct ip_reassdata *tmp;
+      LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_reass_tmr: timer timed out\n"));
+      tmp = r;
+      /* get the next pointer before freeing */
+      r = r->next;
+      /* free the helper struct and all enqueued pbufs */
+      ip_reass_free_complete_datagram(tmp, prev);
+     }
+   }
+}
+
+/**
+ * Free a datagram (struct ip_reassdata) and all its pbufs.
+ * Updates the total count of enqueued pbufs (ip_reass_pbufcount),
+ * SNMP counters and sends an ICMP time exceeded packet.
+ *
+ * @param ipr datagram to free
+ * @param prev the previous datagram in the linked list
+ * @return the number of pbufs freed
+ */
+static int
+ip_reass_free_complete_datagram(struct ip_reassdata *ipr, struct ip_reassdata *prev)
+{
+  u16_t pbufs_freed = 0;
+  u8_t clen;
+  struct pbuf *p;
+  struct ip_reass_helper *iprh;
+
+  LWIP_ASSERT("prev != ipr", prev != ipr);
+  if (prev != NULL) {
+    LWIP_ASSERT("prev->next == ipr", prev->next == ipr);
+  }
+
+  snmp_inc_ipreasmfails();
+#if LWIP_ICMP
+  iprh = (struct ip_reass_helper *)ipr->p->payload;
+  if (iprh->start == 0) {
+    /* The first fragment was received, send ICMP time exceeded. */
+    /* First, de-queue the first pbuf from r->p. */
+    p = ipr->p;
+    ipr->p = iprh->next_pbuf;
+    /* Then, copy the original header into it. */
+    SMEMCPY(p->payload, &ipr->iphdr, IP_HLEN);
+    icmp_time_exceeded(p, ICMP_TE_FRAG);
+    clen = pbuf_clen(p);
+    LWIP_ASSERT("pbufs_freed + clen <= 0xffff", pbufs_freed + clen <= 0xffff);
+    pbufs_freed += clen;
+    pbuf_free(p);
+  }
+#endif /* LWIP_ICMP */
+
+  /* First, free all received pbufs.  The individual pbufs need to be released 
+     separately as they have not yet been chained */
+  p = ipr->p;
+  while (p != NULL) {
+    struct pbuf *pcur;
+    iprh = (struct ip_reass_helper *)p->payload;
+    pcur = p;
+    /* get the next pointer before freeing */
+    p = iprh->next_pbuf;
+    clen = pbuf_clen(pcur);
+    LWIP_ASSERT("pbufs_freed + clen <= 0xffff", pbufs_freed + clen <= 0xffff);
+    pbufs_freed += clen;
+    pbuf_free(pcur);
+  }
+  /* Then, unchain the struct ip_reassdata from the list and free it. */
+  ip_reass_dequeue_datagram(ipr, prev);
+  LWIP_ASSERT("ip_reass_pbufcount >= clen", ip_reass_pbufcount >= pbufs_freed);
+  ip_reass_pbufcount -= pbufs_freed;
+
+  return pbufs_freed;
+}
+
+#if IP_REASS_FREE_OLDEST
+/**
+ * Free the oldest datagram to make room for enqueueing new fragments.
+ * The datagram 'fraghdr' belongs to is not freed!
+ *
+ * @param fraghdr IP header of the current fragment
+ * @param pbufs_needed number of pbufs needed to enqueue
+ *        (used for freeing other datagrams if not enough space)
+ * @return the number of pbufs freed
+ */
+static int
+ip_reass_remove_oldest_datagram(struct ip_hdr *fraghdr, int pbufs_needed)
+{
+  /* @todo Can't we simply remove the last datagram in the
+   *       linked list behind reassdatagrams?
+   */
+  struct ip_reassdata *r, *oldest, *prev;
+  int pbufs_freed = 0, pbufs_freed_current;
+  int other_datagrams;
+
+  /* Free datagrams until being allowed to enqueue 'pbufs_needed' pbufs,
+   * but don't free the datagram that 'fraghdr' belongs to! */
+  do {
+    oldest = NULL;
+    prev = NULL;
+    other_datagrams = 0;
+    r = reassdatagrams;
+    while (r != NULL) {
+      if (!IP_ADDRESSES_AND_ID_MATCH(&r->iphdr, fraghdr)) {
+        /* Not the same datagram as fraghdr */
+        other_datagrams++;
+        if (oldest == NULL) {
+          oldest = r;
+        } else if (r->timer <= oldest->timer) {
+          /* older than the previous oldest */
+          oldest = r;
+        }
+      }
+      if (r->next != NULL) {
+        prev = r;
+      }
+      r = r->next;
+    }
+    if (oldest != NULL) {
+      pbufs_freed_current = ip_reass_free_complete_datagram(oldest, prev);
+      pbufs_freed += pbufs_freed_current;
+    }
+  } while ((pbufs_freed < pbufs_needed) && (other_datagrams > 1));
+  return pbufs_freed;
+}
+#endif /* IP_REASS_FREE_OLDEST */
+
+/**
+ * Enqueues a new fragment into the fragment queue
+ * @param fraghdr points to the new fragments IP hdr
+ * @param clen number of pbufs needed to enqueue (used for freeing other datagrams if not enough space)
+ * @return A pointer to the queue location into which the fragment was enqueued
+ */
+static struct ip_reassdata*
+ip_reass_enqueue_new_datagram(struct ip_hdr *fraghdr, int clen)
+{
+  struct ip_reassdata* ipr;
+  /* No matching previous fragment found, allocate a new reassdata struct */
+  ipr = (struct ip_reassdata *)memp_malloc(MEMP_REASSDATA);
+  if (ipr == NULL) {
+#if IP_REASS_FREE_OLDEST
+    if (ip_reass_remove_oldest_datagram(fraghdr, clen) >= clen) {
+      ipr = (struct ip_reassdata *)memp_malloc(MEMP_REASSDATA);
+    }
+    if (ipr == NULL)
+#endif /* IP_REASS_FREE_OLDEST */
+    {
+      IPFRAG_STATS_INC(ip_frag.memerr);
+      LWIP_DEBUGF(IP_REASS_DEBUG,("Failed to alloc reassdata struct\n"));
+      return NULL;
+    }
+  }
+  memset(ipr, 0, sizeof(struct ip_reassdata));
+  ipr->timer = IP_REASS_MAXAGE;
+
+  /* enqueue the new structure to the front of the list */
+  ipr->next = reassdatagrams;
+  reassdatagrams = ipr;
+  /* copy the ip header for later tests and input */
+  /* @todo: no ip options supported? */
+  SMEMCPY(&(ipr->iphdr), fraghdr, IP_HLEN);
+  return ipr;
+}
+
+/**
+ * Dequeues a datagram from the datagram queue. Doesn't deallocate the pbufs.
+ * @param ipr points to the queue entry to dequeue
+ */
+static void
+ip_reass_dequeue_datagram(struct ip_reassdata *ipr, struct ip_reassdata *prev)
+{
+  
+  /* dequeue the reass struct  */
+  if (reassdatagrams == ipr) {
+    /* it was the first in the list */
+    reassdatagrams = ipr->next;
+  } else {
+    /* it wasn't the first, so it must have a valid 'prev' */
+    LWIP_ASSERT("sanity check linked list", prev != NULL);
+    prev->next = ipr->next;
+  }
+
+  /* now we can free the ip_reass struct */
+  memp_free(MEMP_REASSDATA, ipr);
+}
+
+/**
+ * Chain a new pbuf into the pbuf list that composes the datagram.  The pbuf list
+ * will grow over time as  new pbufs are rx.
+ * Also checks that the datagram passes basic continuity checks (if the last
+ * fragment was received at least once).
+ * @param root_p points to the 'root' pbuf for the current datagram being assembled.
+ * @param new_p points to the pbuf for the current fragment
+ * @return 0 if invalid, >0 otherwise
+ */
+static int
+ip_reass_chain_frag_into_datagram_and_validate(struct ip_reassdata *ipr, struct pbuf *new_p)
+{
+  struct ip_reass_helper *iprh, *iprh_tmp, *iprh_prev=NULL;
+  struct pbuf *q;
+  u16_t offset,len;
+  struct ip_hdr *fraghdr;
+  int valid = 1;
+
+  /* Extract length and fragment offset from current fragment */
+  fraghdr = (struct ip_hdr*)new_p->payload; 
+  len = ntohs(IPH_LEN(fraghdr)) - IPH_HL(fraghdr) * 4;
+  offset = (ntohs(IPH_OFFSET(fraghdr)) & IP_OFFMASK) * 8;
+
+  /* overwrite the fragment's ip header from the pbuf with our helper struct,
+   * and setup the embedded helper structure. */
+  /* make sure the struct ip_reass_helper fits into the IP header */
+  LWIP_ASSERT("sizeof(struct ip_reass_helper) <= IP_HLEN",
+              sizeof(struct ip_reass_helper) <= IP_HLEN);
+  iprh = (struct ip_reass_helper*)new_p->payload;
+  iprh->next_pbuf = NULL;
+  iprh->start = offset;
+  iprh->end = offset + len;
+
+  /* Iterate through until we either get to the end of the list (append),
+   * or we find on with a larger offset (insert). */
+  for (q = ipr->p; q != NULL;) {
+    iprh_tmp = (struct ip_reass_helper*)q->payload;
+    if (iprh->start < iprh_tmp->start) {
+      /* the new pbuf should be inserted before this */
+      iprh->next_pbuf = q;
+      if (iprh_prev != NULL) {
+        /* not the fragment with the lowest offset */
+#if IP_REASS_CHECK_OVERLAP
+        if ((iprh->start < iprh_prev->end) || (iprh->end > iprh_tmp->start)) {
+          /* fragment overlaps with previous or following, throw away */
+          goto freepbuf;
+        }
+#endif /* IP_REASS_CHECK_OVERLAP */
+        iprh_prev->next_pbuf = new_p;
+      } else {
+        /* fragment with the lowest offset */
+        ipr->p = new_p;
+      }
+      break;
+    } else if(iprh->start == iprh_tmp->start) {
+      /* received the same datagram twice: no need to keep the datagram */
+      goto freepbuf;
+#if IP_REASS_CHECK_OVERLAP
+    } else if(iprh->start < iprh_tmp->end) {
+      /* overlap: no need to keep the new datagram */
+      goto freepbuf;
+#endif /* IP_REASS_CHECK_OVERLAP */
+    } else {
+      /* Check if the fragments received so far have no wholes. */
+      if (iprh_prev != NULL) {
+        if (iprh_prev->end != iprh_tmp->start) {
+          /* There is a fragment missing between the current
+           * and the previous fragment */
+          valid = 0;
+        }
+      }
+    }
+    q = iprh_tmp->next_pbuf;
+    iprh_prev = iprh_tmp;
+  }
+
+  /* If q is NULL, then we made it to the end of the list. Determine what to do now */
+  if (q == NULL) {
+    if (iprh_prev != NULL) {
+      /* this is (for now), the fragment with the highest offset:
+       * chain it to the last fragment */
+#if IP_REASS_CHECK_OVERLAP
+      LWIP_ASSERT("check fragments don't overlap", iprh_prev->end <= iprh->start);
+#endif /* IP_REASS_CHECK_OVERLAP */
+      iprh_prev->next_pbuf = new_p;
+      if (iprh_prev->end != iprh->start) {
+        valid = 0;
+      }
+    } else {
+#if IP_REASS_CHECK_OVERLAP
+      LWIP_ASSERT("no previous fragment, this must be the first fragment!",
+        ipr->p == NULL);
+#endif /* IP_REASS_CHECK_OVERLAP */
+      /* this is the first fragment we ever received for this ip datagram */
+      ipr->p = new_p;
+    }
+  }
+
+  /* At this point, the validation part begins: */
+  /* If we already received the last fragment */
+  if ((ipr->flags & IP_REASS_FLAG_LASTFRAG) != 0) {
+    /* and had no wholes so far */
+    if (valid) {
+      /* then check if the rest of the fragments is here */
+      /* Check if the queue starts with the first datagram */
+      if (((struct ip_reass_helper*)ipr->p->payload)->start != 0) {
+        valid = 0;
+      } else {
+        /* and check that there are no wholes after this datagram */
+        iprh_prev = iprh;
+        q = iprh->next_pbuf;
+        while (q != NULL) {
+          iprh = (struct ip_reass_helper*)q->payload;
+          if (iprh_prev->end != iprh->start) {
+            valid = 0;
+            break;
+          }
+          iprh_prev = iprh;
+          q = iprh->next_pbuf;
+        }
+        /* if still valid, all fragments are received
+         * (because to the MF==0 already arrived */
+        if (valid) {
+          LWIP_ASSERT("sanity check", ipr->p != NULL);
+          LWIP_ASSERT("sanity check",
+            ((struct ip_reass_helper*)ipr->p->payload) != iprh);
+          LWIP_ASSERT("validate_datagram:next_pbuf!=NULL",
+            iprh->next_pbuf == NULL);
+          LWIP_ASSERT("validate_datagram:datagram end!=datagram len",
+            iprh->end == ipr->datagram_len);
+        }
+      }
+    }
+    /* If valid is 0 here, there are some fragments missing in the middle
+     * (since MF == 0 has already arrived). Such datagrams simply time out if
+     * no more fragments are received... */
+    return valid;
+  }
+  /* If we come here, not all fragments were received, yet! */
+  return 0; /* not yet valid! */
+#if IP_REASS_CHECK_OVERLAP
+freepbuf:
+  ip_reass_pbufcount -= pbuf_clen(new_p);
+  pbuf_free(new_p);
+  return 0;
+#endif /* IP_REASS_CHECK_OVERLAP */
+}
+
+/**
+ * Reassembles incoming IP fragments into an IP datagram.
+ *
+ * @param p points to a pbuf chain of the fragment
+ * @return NULL if reassembly is incomplete, ? otherwise
+ */
+struct pbuf *
+ip_reass(struct pbuf *p)
+{
+  struct pbuf *r;
+  struct ip_hdr *fraghdr;
+  struct ip_reassdata *ipr;
+  struct ip_reass_helper *iprh;
+  u16_t offset, len;
+  u8_t clen;
+  struct ip_reassdata *ipr_prev = NULL;
+
+  IPFRAG_STATS_INC(ip_frag.recv);
+  snmp_inc_ipreasmreqds();
+
+  fraghdr = (struct ip_hdr*)p->payload;
+
+  if ((IPH_HL(fraghdr) * 4) != IP_HLEN) {
+    LWIP_DEBUGF(IP_REASS_DEBUG,("ip_reass: IP options currently not supported!\n"));
+    IPFRAG_STATS_INC(ip_frag.err);
+    goto nullreturn;
+  }
+
+  offset = (ntohs(IPH_OFFSET(fraghdr)) & IP_OFFMASK) * 8;
+  len = ntohs(IPH_LEN(fraghdr)) - IPH_HL(fraghdr) * 4;
+
+  /* Check if we are allowed to enqueue more datagrams. */
+  clen = pbuf_clen(p);
+  if ((ip_reass_pbufcount + clen) > IP_REASS_MAX_PBUFS) {
+#if IP_REASS_FREE_OLDEST
+    if (!ip_reass_remove_oldest_datagram(fraghdr, clen) ||
+        ((ip_reass_pbufcount + clen) > IP_REASS_MAX_PBUFS))
+#endif /* IP_REASS_FREE_OLDEST */
+    {
+      /* No datagram could be freed and still too many pbufs enqueued */
+      LWIP_DEBUGF(IP_REASS_DEBUG,("ip_reass: Overflow condition: pbufct=%d, clen=%d, MAX=%d\n",
+        ip_reass_pbufcount, clen, IP_REASS_MAX_PBUFS));
+      IPFRAG_STATS_INC(ip_frag.memerr);
+      /* @todo: send ICMP time exceeded here? */
+      /* drop this pbuf */
+      goto nullreturn;
+    }
+  }
+
+  /* Look for the datagram the fragment belongs to in the current datagram queue,
+   * remembering the previous in the queue for later dequeueing. */
+  for (ipr = reassdatagrams; ipr != NULL; ipr = ipr->next) {
+    /* Check if the incoming fragment matches the one currently present
+       in the reassembly buffer. If so, we proceed with copying the
+       fragment into the buffer. */
+    if (IP_ADDRESSES_AND_ID_MATCH(&ipr->iphdr, fraghdr)) {
+      LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_reass: matching previous fragment ID=%"X16_F"\n",
+        ntohs(IPH_ID(fraghdr))));
+      IPFRAG_STATS_INC(ip_frag.cachehit);
+      break;
+    }
+    ipr_prev = ipr;
+  }
+
+  if (ipr == NULL) {
+  /* Enqueue a new datagram into the datagram queue */
+    ipr = ip_reass_enqueue_new_datagram(fraghdr, clen);
+    /* Bail if unable to enqueue */
+    if(ipr == NULL) {
+      goto nullreturn;
+    }
+  } else {
+    if (((ntohs(IPH_OFFSET(fraghdr)) & IP_OFFMASK) == 0) && 
+      ((ntohs(IPH_OFFSET(&ipr->iphdr)) & IP_OFFMASK) != 0)) {
+      /* ipr->iphdr is not the header from the first fragment, but fraghdr is
+       * -> copy fraghdr into ipr->iphdr since we want to have the header
+       * of the first fragment (for ICMP time exceeded and later, for copying
+       * all options, if supported)*/
+      SMEMCPY(&ipr->iphdr, fraghdr, IP_HLEN);
+    }
+  }
+  /* Track the current number of pbufs current 'in-flight', in order to limit 
+  the number of fragments that may be enqueued at any one time */
+  ip_reass_pbufcount += clen;
+
+  /* At this point, we have either created a new entry or pointing 
+   * to an existing one */
+
+  /* check for 'no more fragments', and update queue entry*/
+  if ((IPH_OFFSET(fraghdr) & PP_NTOHS(IP_MF)) == 0) {
+    ipr->flags |= IP_REASS_FLAG_LASTFRAG;
+    ipr->datagram_len = offset + len;
+    LWIP_DEBUGF(IP_REASS_DEBUG,
+     ("ip_reass: last fragment seen, total len %"S16_F"\n",
+      ipr->datagram_len));
+  }
+  /* find the right place to insert this pbuf */
+  /* @todo: trim pbufs if fragments are overlapping */
+  if (ip_reass_chain_frag_into_datagram_and_validate(ipr, p)) {
+    /* the totally last fragment (flag more fragments = 0) was received at least
+     * once AND all fragments are received */
+    ipr->datagram_len += IP_HLEN;
+
+    /* save the second pbuf before copying the header over the pointer */
+    r = ((struct ip_reass_helper*)ipr->p->payload)->next_pbuf;
+
+    /* copy the original ip header back to the first pbuf */
+    fraghdr = (struct ip_hdr*)(ipr->p->payload);
+    SMEMCPY(fraghdr, &ipr->iphdr, IP_HLEN);
+    IPH_LEN_SET(fraghdr, htons(ipr->datagram_len));
+    IPH_OFFSET_SET(fraghdr, 0);
+    IPH_CHKSUM_SET(fraghdr, 0);
+    /* @todo: do we need to set calculate the correct checksum? */
+    IPH_CHKSUM_SET(fraghdr, inet_chksum(fraghdr, IP_HLEN));
+
+    p = ipr->p;
+
+    /* chain together the pbufs contained within the reass_data list. */
+    while(r != NULL) {
+      iprh = (struct ip_reass_helper*)r->payload;
+
+      /* hide the ip header for every succeding fragment */
+      pbuf_header(r, -IP_HLEN);
+      pbuf_cat(p, r);
+      r = iprh->next_pbuf;
+    }
+    /* release the sources allocate for the fragment queue entry */
+    ip_reass_dequeue_datagram(ipr, ipr_prev);
+
+    /* and adjust the number of pbufs currently queued for reassembly. */
+    ip_reass_pbufcount -= pbuf_clen(p);
+
+    /* Return the pbuf chain */
+    return p;
+  }
+  /* the datagram is not (yet?) reassembled completely */
+  LWIP_DEBUGF(IP_REASS_DEBUG,("ip_reass_pbufcount: %d out\n", ip_reass_pbufcount));
+  return NULL;
+
+nullreturn:
+  LWIP_DEBUGF(IP_REASS_DEBUG,("ip_reass: nullreturn\n"));
+  IPFRAG_STATS_INC(ip_frag.drop);
+  pbuf_free(p);
+  return NULL;
+}
+#endif /* IP_REASSEMBLY */
+
+#if IP_FRAG
+#if IP_FRAG_USES_STATIC_BUF
+static u8_t buf[LWIP_MEM_ALIGN_SIZE(IP_FRAG_MAX_MTU + MEM_ALIGNMENT - 1)];
+#else /* IP_FRAG_USES_STATIC_BUF */
+
+#if !LWIP_NETIF_TX_SINGLE_PBUF
+/** Allocate a new struct pbuf_custom_ref */
+static struct pbuf_custom_ref*
+ip_frag_alloc_pbuf_custom_ref(void)
+{
+  return (struct pbuf_custom_ref*)memp_malloc(MEMP_FRAG_PBUF);
+}
+
+/** Free a struct pbuf_custom_ref */
+static void
+ip_frag_free_pbuf_custom_ref(struct pbuf_custom_ref* p)
+{
+  LWIP_ASSERT("p != NULL", p != NULL);
+  memp_free(MEMP_FRAG_PBUF, p);
+}
+
+/** Free-callback function to free a 'struct pbuf_custom_ref', called by
+ * pbuf_free. */
+static void
+ipfrag_free_pbuf_custom(struct pbuf *p)
+{
+  struct pbuf_custom_ref *pcr = (struct pbuf_custom_ref*)p;
+  LWIP_ASSERT("pcr != NULL", pcr != NULL);
+  LWIP_ASSERT("pcr == p", (void*)pcr == (void*)p);
+  if (pcr->original != NULL) {
+    pbuf_free(pcr->original);
+  }
+  ip_frag_free_pbuf_custom_ref(pcr);
+}
+#endif /* !LWIP_NETIF_TX_SINGLE_PBUF */
+#endif /* IP_FRAG_USES_STATIC_BUF */
+
+/**
+ * Fragment an IP datagram if too large for the netif.
+ *
+ * Chop the datagram in MTU sized chunks and send them in order
+ * by using a fixed size static memory buffer (PBUF_REF) or
+ * point PBUF_REFs into p (depending on IP_FRAG_USES_STATIC_BUF).
+ *
+ * @param p ip packet to send
+ * @param netif the netif on which to send
+ * @param dest destination ip address to which to send
+ *
+ * @return ERR_OK if sent successfully, err_t otherwise
+ */
+err_t 
+ip_frag(struct pbuf *p, struct netif *netif, ip_addr_t *dest)
+{
+  struct pbuf *rambuf;
+#if IP_FRAG_USES_STATIC_BUF
+  struct pbuf *header;
+#else
+#if !LWIP_NETIF_TX_SINGLE_PBUF
+  struct pbuf *newpbuf;
+#endif
+  struct ip_hdr *original_iphdr;
+#endif
+  struct ip_hdr *iphdr;
+  u16_t nfb;
+  u16_t left, cop;
+  u16_t mtu = netif->mtu;
+  u16_t ofo, omf;
+  u16_t last;
+  u16_t poff = IP_HLEN;
+  u16_t tmp;
+#if !IP_FRAG_USES_STATIC_BUF && !LWIP_NETIF_TX_SINGLE_PBUF
+  u16_t newpbuflen = 0;
+  u16_t left_to_copy;
+#endif
+
+  /* Get a RAM based MTU sized pbuf */
+#if IP_FRAG_USES_STATIC_BUF
+  /* When using a static buffer, we use a PBUF_REF, which we will
+   * use to reference the packet (without link header).
+   * Layer and length is irrelevant.
+   */
+  rambuf = pbuf_alloc(PBUF_LINK, 0, PBUF_REF);
+  if (rambuf == NULL) {
+    LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_frag: pbuf_alloc(PBUF_LINK, 0, PBUF_REF) failed\n"));
+    return ERR_MEM;
+  }
+  rambuf->tot_len = rambuf->len = mtu;
+  rambuf->payload = LWIP_MEM_ALIGN((void *)buf);
+
+  /* Copy the IP header in it */
+  iphdr = (struct ip_hdr *)rambuf->payload;
+  SMEMCPY(iphdr, p->payload, IP_HLEN);
+#else /* IP_FRAG_USES_STATIC_BUF */
+  original_iphdr = (struct ip_hdr *)p->payload;
+  iphdr = original_iphdr;
+#endif /* IP_FRAG_USES_STATIC_BUF */
+
+  /* Save original offset */
+  tmp = ntohs(IPH_OFFSET(iphdr));
+  ofo = tmp & IP_OFFMASK;
+  omf = tmp & IP_MF;
+
+  left = p->tot_len - IP_HLEN;
+
+  nfb = (mtu - IP_HLEN) / 8;
+
+  while (left) {
+    last = (left <= mtu - IP_HLEN);
+
+    /* Set new offset and MF flag */
+    tmp = omf | (IP_OFFMASK & (ofo));
+    if (!last) {
+      tmp = tmp | IP_MF;
+    }
+
+    /* Fill this fragment */
+    cop = last ? left : nfb * 8;
+
+#if IP_FRAG_USES_STATIC_BUF
+    poff += pbuf_copy_partial(p, (u8_t*)iphdr + IP_HLEN, cop, poff);
+#else /* IP_FRAG_USES_STATIC_BUF */
+#if LWIP_NETIF_TX_SINGLE_PBUF
+    rambuf = pbuf_alloc(PBUF_IP, cop, PBUF_RAM);
+    if (rambuf == NULL) {
+      return ERR_MEM;
+    }
+    LWIP_ASSERT("this needs a pbuf in one piece!",
+      (rambuf->len == rambuf->tot_len) && (rambuf->next == NULL));
+    poff += pbuf_copy_partial(p, rambuf->payload, cop, poff);
+    /* make room for the IP header */
+    if(pbuf_header(rambuf, IP_HLEN)) {
+      pbuf_free(rambuf);
+      return ERR_MEM;
+    }
+    /* fill in the IP header */
+    SMEMCPY(rambuf->payload, original_iphdr, IP_HLEN);
+    iphdr = rambuf->payload;
+#else /* LWIP_NETIF_TX_SINGLE_PBUF */
+    /* When not using a static buffer, create a chain of pbufs.
+     * The first will be a PBUF_RAM holding the link and IP header.
+     * The rest will be PBUF_REFs mirroring the pbuf chain to be fragged,
+     * but limited to the size of an mtu.
+     */
+    rambuf = pbuf_alloc(PBUF_LINK, IP_HLEN, PBUF_RAM);
+    if (rambuf == NULL) {
+      return ERR_MEM;
+    }
+    LWIP_ASSERT("this needs a pbuf in one piece!",
+                (p->len >= (IP_HLEN)));
+    SMEMCPY(rambuf->payload, original_iphdr, IP_HLEN);
+    iphdr = (struct ip_hdr *)rambuf->payload;
+
+    /* Can just adjust p directly for needed offset. */
+    p->payload = (u8_t *)p->payload + poff;
+    p->len -= poff;
+
+    left_to_copy = cop;
+    while (left_to_copy) {
+      struct pbuf_custom_ref *pcr;
+      newpbuflen = (left_to_copy < p->len) ? left_to_copy : p->len;
+      /* Is this pbuf already empty? */
+      if (!newpbuflen) {
+        p = p->next;
+        continue;
+      }
+      pcr = ip_frag_alloc_pbuf_custom_ref();
+      if (pcr == NULL) {
+        pbuf_free(rambuf);
+        return ERR_MEM;
+      }
+      /* Mirror this pbuf, although we might not need all of it. */
+      newpbuf = pbuf_alloced_custom(PBUF_RAW, newpbuflen, PBUF_REF, &pcr->pc, p->payload, newpbuflen);
+      if (newpbuf == NULL) {
+        ip_frag_free_pbuf_custom_ref(pcr);
+        pbuf_free(rambuf);
+        return ERR_MEM;
+      }
+      pbuf_ref(p);
+      pcr->original = p;
+      pcr->pc.custom_free_function = ipfrag_free_pbuf_custom;
+
+      /* Add it to end of rambuf's chain, but using pbuf_cat, not pbuf_chain
+       * so that it is removed when pbuf_dechain is later called on rambuf.
+       */
+      pbuf_cat(rambuf, newpbuf);
+      left_to_copy -= newpbuflen;
+      if (left_to_copy) {
+        p = p->next;
+      }
+    }
+    poff = newpbuflen;
+#endif /* LWIP_NETIF_TX_SINGLE_PBUF */
+#endif /* IP_FRAG_USES_STATIC_BUF */
+
+    /* Correct header */
+    IPH_OFFSET_SET(iphdr, htons(tmp));
+    IPH_LEN_SET(iphdr, htons(cop + IP_HLEN));
+    IPH_CHKSUM_SET(iphdr, 0);
+    IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, IP_HLEN));
+
+#if IP_FRAG_USES_STATIC_BUF
+    if (last) {
+      pbuf_realloc(rambuf, left + IP_HLEN);
+    }
+
+    /* This part is ugly: we alloc a RAM based pbuf for 
+     * the link level header for each chunk and then 
+     * free it.A PBUF_ROM style pbuf for which pbuf_header
+     * worked would make things simpler.
+     */
+    header = pbuf_alloc(PBUF_LINK, 0, PBUF_RAM);
+    if (header != NULL) {
+      pbuf_chain(header, rambuf);
+      netif->output(netif, header, dest);
+      IPFRAG_STATS_INC(ip_frag.xmit);
+      snmp_inc_ipfragcreates();
+      pbuf_free(header);
+    } else {
+      LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_frag: pbuf_alloc() for header failed\n"));
+      pbuf_free(rambuf);
+      return ERR_MEM;
+    }
+#else /* IP_FRAG_USES_STATIC_BUF */
+    /* No need for separate header pbuf - we allowed room for it in rambuf
+     * when allocated.
+     */
+    netif->output(netif, rambuf, dest);
+    IPFRAG_STATS_INC(ip_frag.xmit);
+
+    /* Unfortunately we can't reuse rambuf - the hardware may still be
+     * using the buffer. Instead we free it (and the ensuing chain) and
+     * recreate it next time round the loop. If we're lucky the hardware
+     * will have already sent the packet, the free will really free, and
+     * there will be zero memory penalty.
+     */
+    
+    pbuf_free(rambuf);
+#endif /* IP_FRAG_USES_STATIC_BUF */
+    left -= cop;
+    ofo += nfb;
+  }
+#if IP_FRAG_USES_STATIC_BUF
+  pbuf_free(rambuf);
+#endif /* IP_FRAG_USES_STATIC_BUF */
+  snmp_inc_ipfragoks();
+  return ERR_OK;
+}
+#endif /* IP_FRAG */

src/lwip-1.4.1/src/core/ipv6/README

@@ -0,0 +1 @@
+IPv6 support in lwIP is very experimental.

src/lwip-1.4.1/src/core/ipv6/icmp6.c

@@ -0,0 +1,179 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+/* Some ICMP messages should be passed to the transport protocols. This
+   is not implemented. */
+
+#include "lwip/opt.h"
+
+#if LWIP_ICMP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/icmp.h"
+#include "lwip/inet.h"
+#include "lwip/ip.h"
+#include "lwip/def.h"
+#include "lwip/stats.h"
+
+void
+icmp_input(struct pbuf *p, struct netif *inp)
+{
+  u8_t type;
+  struct icmp_echo_hdr *iecho;
+  struct ip_hdr *iphdr;
+  struct ip_addr tmpaddr;
+
+  ICMP_STATS_INC(icmp.recv);
+
+  /* TODO: check length before accessing payload! */
+
+  type = ((u8_t *)p->payload)[0];
+
+  switch (type) {
+  case ICMP6_ECHO:
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: ping\n"));
+
+    if (p->tot_len < sizeof(struct icmp_echo_hdr)) {
+      LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: bad ICMP echo received\n"));
+
+      pbuf_free(p);
+      ICMP_STATS_INC(icmp.lenerr);
+      return;
+    }
+    iecho = p->payload;
+    iphdr = (struct ip_hdr *)((u8_t *)p->payload - IP_HLEN);
+    if (inet_chksum_pbuf(p) != 0) {
+      LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: checksum failed for received ICMP echo (%"X16_F")\n", inet_chksum_pseudo(p, &(iphdr->src), &(iphdr->dest), IP_PROTO_ICMP, p->tot_len)));
+      ICMP_STATS_INC(icmp.chkerr);
+    /*      return;*/
+    }
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp: p->len %"S16_F" p->tot_len %"S16_F"\n", p->len, p->tot_len));
+    ip_addr_set(&tmpaddr, &(iphdr->src));
+    ip_addr_set(&(iphdr->src), &(iphdr->dest));
+    ip_addr_set(&(iphdr->dest), &tmpaddr);
+    iecho->type = ICMP6_ER;
+    /* adjust the checksum */
+    if (iecho->chksum >= htons(0xffff - (ICMP6_ECHO << 8))) {
+      iecho->chksum += htons(ICMP6_ECHO << 8) + 1;
+    } else {
+      iecho->chksum += htons(ICMP6_ECHO << 8);
+    }
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: checksum failed for received ICMP echo (%"X16_F")\n", inet_chksum_pseudo(p, &(iphdr->src), &(iphdr->dest), IP_PROTO_ICMP, p->tot_len)));
+    ICMP_STATS_INC(icmp.xmit);
+
+    /*    LWIP_DEBUGF("icmp: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len);*/
+    ip_output_if (p, &(iphdr->src), IP_HDRINCL,
+     iphdr->hoplim, IP_PROTO_ICMP, inp);
+    break;
+  default:
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: ICMP type %"S16_F" not supported.\n", (s16_t)type));
+    ICMP_STATS_INC(icmp.proterr);
+    ICMP_STATS_INC(icmp.drop);
+  }
+
+  pbuf_free(p);
+}
+
+void
+icmp_dest_unreach(struct pbuf *p, enum icmp_dur_type t)
+{
+  struct pbuf *q;
+  struct ip_hdr *iphdr;
+  struct icmp_dur_hdr *idur;
+
+  /* @todo: can this be PBUF_LINK instead of PBUF_IP? */
+  q = pbuf_alloc(PBUF_IP, 8 + IP_HLEN + 8, PBUF_RAM);
+  /* ICMP header + IP header + 8 bytes of data */
+  if (q == NULL) {
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp_dest_unreach: failed to allocate pbuf for ICMP packet.\n"));
+    pbuf_free(p);
+    return;
+  }
+  LWIP_ASSERT("check that first pbuf can hold icmp message",
+             (q->len >= (8 + IP_HLEN + 8)));
+
+  iphdr = p->payload;
+
+  idur = q->payload;
+  idur->type = (u8_t)ICMP6_DUR;
+  idur->icode = (u8_t)t;
+
+  SMEMCPY((u8_t *)q->payload + 8, p->payload, IP_HLEN + 8);
+
+  /* calculate checksum */
+  idur->chksum = 0;
+  idur->chksum = inet_chksum(idur, q->len);
+  ICMP_STATS_INC(icmp.xmit);
+
+  ip_output(q, NULL,
+      (struct ip_addr *)&(iphdr->src), ICMP_TTL, IP_PROTO_ICMP);
+  pbuf_free(q);
+}
+
+void
+icmp_time_exceeded(struct pbuf *p, enum icmp_te_type t)
+{
+  struct pbuf *q;
+  struct ip_hdr *iphdr;
+  struct icmp_te_hdr *tehdr;
+
+  LWIP_DEBUGF(ICMP_DEBUG, ("icmp_time_exceeded\n"));
+
+  /* @todo: can this be PBUF_LINK instead of PBUF_IP? */
+  q = pbuf_alloc(PBUF_IP, 8 + IP_HLEN + 8, PBUF_RAM);
+  /* ICMP header + IP header + 8 bytes of data */
+  if (q == NULL) {
+    LWIP_DEBUGF(ICMP_DEBUG, ("icmp_dest_unreach: failed to allocate pbuf for ICMP packet.\n"));
+    pbuf_free(p);
+    return;
+  }
+  LWIP_ASSERT("check that first pbuf can hold icmp message",
+             (q->len >= (8 + IP_HLEN + 8)));
+
+  iphdr = p->payload;
+
+  tehdr = q->payload;
+  tehdr->type = (u8_t)ICMP6_TE;
+  tehdr->icode = (u8_t)t;
+
+  /* copy fields from original packet */
+  SMEMCPY((u8_t *)q->payload + 8, (u8_t *)p->payload, IP_HLEN + 8);
+
+  /* calculate checksum */
+  tehdr->chksum = 0;
+  tehdr->chksum = inet_chksum(tehdr, q->len);
+  ICMP_STATS_INC(icmp.xmit);
+  ip_output(q, NULL,
+      (struct ip_addr *)&(iphdr->src), ICMP_TTL, IP_PROTO_ICMP);
+  pbuf_free(q);
+}
+
+#endif /* LWIP_ICMP */

src/lwip-1.4.1/src/core/ipv6/inet6.c

@@ -0,0 +1,163 @@
+/**
+ * @file
+ * Functions common to all TCP/IPv6 modules, such as the Internet checksum and the
+ * byte order functions.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/def.h"
+#include "lwip/inet.h"
+
+/* chksum:
+ *
+ * Sums up all 16 bit words in a memory portion. Also includes any odd byte.
+ * This function is used by the other checksum functions.
+ *
+ * For now, this is not optimized. Must be optimized for the particular processor
+ * arcitecture on which it is to run. Preferebly coded in assembler.
+ */
+
+static u32_t
+chksum(void *dataptr, u16_t len)
+{
+  u16_t *sdataptr = dataptr;
+  u32_t acc;
+  
+  
+  for(acc = 0; len > 1; len -= 2) {
+    acc += *sdataptr++;
+  }
+
+  /* add up any odd byte */
+  if (len == 1) {
+    acc += htons((u16_t)(*(u8_t *)dataptr) << 8);
+  }
+
+  return acc;
+
+}
+
+/* inet_chksum_pseudo:
+ *
+ * Calculates the pseudo Internet checksum used by TCP and UDP for a pbuf chain.
+ */
+
+u16_t
+inet_chksum_pseudo(struct pbuf *p,
+       struct ip_addr *src, struct ip_addr *dest,
+       u8_t proto, u32_t proto_len)
+{
+  u32_t acc;
+  struct pbuf *q;
+  u8_t swapped, i;
+
+  acc = 0;
+  swapped = 0;
+  for(q = p; q != NULL; q = q->next) {    
+    acc += chksum(q->payload, q->len);
+    while (acc >> 16) {
+      acc = (acc & 0xffff) + (acc >> 16);
+    }
+    if (q->len % 2 != 0) {
+      swapped = 1 - swapped;
+      acc = ((acc & 0xff) << 8) | ((acc & 0xff00) >> 8);
+    }
+  }
+
+  if (swapped) {
+    acc = ((acc & 0xff) << 8) | ((acc & 0xff00) >> 8);
+  }
+  
+  for(i = 0; i < 8; i++) {
+    acc += ((u16_t *)src->addr)[i] & 0xffff;
+    acc += ((u16_t *)dest->addr)[i] & 0xffff;
+    while (acc >> 16) {
+      acc = (acc & 0xffff) + (acc >> 16);
+    }
+  }
+  acc += (u16_t)htons((u16_t)proto);
+  acc += ((u16_t *)&proto_len)[0] & 0xffff;
+  acc += ((u16_t *)&proto_len)[1] & 0xffff;
+
+  while (acc >> 16) {
+    acc = (acc & 0xffff) + (acc >> 16);
+  }
+  return ~(acc & 0xffff);
+}
+
+/* inet_chksum:
+ *
+ * Calculates the Internet checksum over a portion of memory. Used primarely for IP
+ * and ICMP.
+ */
+
+u16_t
+inet_chksum(void *dataptr, u16_t len)
+{
+  u32_t acc, sum;
+
+  acc = chksum(dataptr, len);
+  sum = (acc & 0xffff) + (acc >> 16);
+  sum += (sum >> 16);
+  return ~(sum & 0xffff);
+}
+
+u16_t
+inet_chksum_pbuf(struct pbuf *p)
+{
+  u32_t acc;
+  struct pbuf *q;
+  u8_t swapped;
+  
+  acc = 0;
+  swapped = 0;
+  for(q = p; q != NULL; q = q->next) {
+    acc += chksum(q->payload, q->len);
+    while (acc >> 16) {
+      acc = (acc & 0xffff) + (acc >> 16);
+    }    
+    if (q->len % 2 != 0) {
+      swapped = 1 - swapped;
+      acc = (acc & 0xff << 8) | (acc & 0xff00 >> 8);
+    }
+  }
+ 
+  if (swapped) {
+    acc = ((acc & 0xff) << 8) | ((acc & 0xff00) >> 8);
+  }
+  return ~(acc & 0xffff);
+}

src/lwip-1.4.1/src/core/ipv6/ip6.c

@@ -0,0 +1,397 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+
+
+/* ip.c
+ *
+ * This is the code for the IP layer for IPv6.
+ *
+ */
+
+
+#include "lwip/opt.h"
+
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/ip.h"
+#include "lwip/inet.h"
+#include "lwip/netif.h"
+#include "lwip/icmp.h"
+#include "lwip/udp.h"
+#include "lwip/tcp_impl.h"
+
+#include "lwip/stats.h"
+
+#include "arch/perf.h"
+
+/* ip_init:
+ *
+ * Initializes the IP layer.
+ */
+
+void
+ip_init(void)
+{
+}
+
+/* ip_route:
+ *
+ * Finds the appropriate network interface for a given IP address. It searches the
+ * list of network interfaces linearly. A match is found if the masked IP address of
+ * the network interface equals the masked IP address given to the function.
+ */
+
+struct netif *
+ip_route(struct ip_addr *dest)
+{
+  struct netif *netif;
+
+  for(netif = netif_list; netif != NULL; netif = netif->next) {
+    if (ip_addr_netcmp(dest, &(netif->ip_addr), &(netif->netmask))) {
+      return netif;
+    }
+  }
+
+  return netif_default;
+}
+
+/* ip_forward:
+ *
+ * Forwards an IP packet. It finds an appropriate route for the packet, decrements
+ * the TTL value of the packet, adjusts the checksum and outputs the packet on the
+ * appropriate interface.
+ */
+
+static void
+ip_forward(struct pbuf *p, struct ip_hdr *iphdr)
+{
+  struct netif *netif;
+
+  PERF_START;
+
+  if ((netif = ip_route((struct ip_addr *)&(iphdr->dest))) == NULL) {
+
+    LWIP_DEBUGF(IP_DEBUG, ("ip_input: no forwarding route found for "));
+#if IP_DEBUG
+    ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest)));
+#endif /* IP_DEBUG */
+    LWIP_DEBUGF(IP_DEBUG, ("\n"));
+    pbuf_free(p);
+    return;
+  }
+  /* Decrement TTL and send ICMP if ttl == 0. */
+  if (--iphdr->hoplim == 0) {
+#if LWIP_ICMP
+    /* Don't send ICMP messages in response to ICMP messages */
+    if (iphdr->nexthdr != IP_PROTO_ICMP) {
+      icmp_time_exceeded(p, ICMP_TE_TTL);
+    }
+#endif /* LWIP_ICMP */
+    pbuf_free(p);
+    return;
+  }
+
+  /* Incremental update of the IP checksum. */
+  /*  if (iphdr->chksum >= htons(0xffff - 0x100)) {
+    iphdr->chksum += htons(0x100) + 1;
+  } else {
+    iphdr->chksum += htons(0x100);
+    }*/
+
+
+  LWIP_DEBUGF(IP_DEBUG, ("ip_forward: forwarding packet to "));
+#if IP_DEBUG
+  ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest)));
+#endif /* IP_DEBUG */
+  LWIP_DEBUGF(IP_DEBUG, ("\n"));
+
+  IP_STATS_INC(ip.fw);
+  IP_STATS_INC(ip.xmit);
+
+  PERF_STOP("ip_forward");
+
+  netif->output(netif, p, (struct ip_addr *)&(iphdr->dest));
+}
+
+/* ip_input:
+ *
+ * This function is called by the network interface device driver when an IP packet is
+ * received. The function does the basic checks of the IP header such as packet size
+ * being at least larger than the header size etc. If the packet was not destined for
+ * us, the packet is forwarded (using ip_forward). The IP checksum is always checked.
+ *
+ * Finally, the packet is sent to the upper layer protocol input function.
+ */
+
+void
+ip_input(struct pbuf *p, struct netif *inp) {
+  struct ip_hdr *iphdr;
+  struct netif *netif;
+
+
+  PERF_START;
+
+#if IP_DEBUG
+  ip_debug_print(p);
+#endif /* IP_DEBUG */
+
+
+  IP_STATS_INC(ip.recv);
+
+  /* identify the IP header */
+  iphdr = p->payload;
+
+
+  if (iphdr->v != 6) {
+    LWIP_DEBUGF(IP_DEBUG, ("IP packet dropped due to bad version number\n"));
+#if IP_DEBUG
+    ip_debug_print(p);
+#endif /* IP_DEBUG */
+    pbuf_free(p);
+    IP_STATS_INC(ip.err);
+    IP_STATS_INC(ip.drop);
+    return;
+  }
+
+  /* is this packet for us? */
+  for(netif = netif_list; netif != NULL; netif = netif->next) {
+#if IP_DEBUG
+    LWIP_DEBUGF(IP_DEBUG, ("ip_input: iphdr->dest "));
+    ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest)));
+    LWIP_DEBUGF(IP_DEBUG, ("netif->ip_addr "));
+    ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest)));
+    LWIP_DEBUGF(IP_DEBUG, ("\n"));
+#endif /* IP_DEBUG */
+    if (ip_addr_cmp(&(iphdr->dest), &(netif->ip_addr))) {
+      break;
+    }
+  }
+
+
+  if (netif == NULL) {
+    /* packet not for us, route or discard */
+#if IP_FORWARD
+    ip_forward(p, iphdr);
+#endif
+    pbuf_free(p);
+    return;
+  }
+
+  pbuf_realloc(p, IP_HLEN + ntohs(iphdr->len));
+
+  /* send to upper layers */
+#if IP_DEBUG
+  /*  LWIP_DEBUGF("ip_input: \n");
+  ip_debug_print(p);
+  LWIP_DEBUGF("ip_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len);*/
+#endif /* IP_DEBUG */
+
+  if(pbuf_header(p, -IP_HLEN)) {
+    LWIP_ASSERT("Can't move over header in packet", 0);
+    return;
+  }
+
+  switch (iphdr->nexthdr) {
+  case IP_PROTO_UDP:
+    udp_input(p, inp);
+    break;
+  case IP_PROTO_TCP:
+    tcp_input(p, inp);
+    break;
+#if LWIP_ICMP
+  case IP_PROTO_ICMP:
+    icmp_input(p, inp);
+    break;
+#endif /* LWIP_ICMP */
+  default:
+#if LWIP_ICMP
+    /* send ICMP destination protocol unreachable */
+    icmp_dest_unreach(p, ICMP_DUR_PROTO);
+#endif /* LWIP_ICMP */
+    pbuf_free(p);
+    LWIP_DEBUGF(IP_DEBUG, ("Unsupported transport protocol %"U16_F"\n",
+          iphdr->nexthdr));
+
+    IP_STATS_INC(ip.proterr);
+    IP_STATS_INC(ip.drop);
+  }
+  PERF_STOP("ip_input");
+}
+
+
+/* ip_output_if:
+ *
+ * Sends an IP packet on a network interface. This function constructs the IP header
+ * and calculates the IP header checksum. If the source IP address is NULL,
+ * the IP address of the outgoing network interface is filled in as source address.
+ */
+
+err_t
+ip_output_if (struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
+       u8_t ttl,
+       u8_t proto, struct netif *netif)
+{
+  struct ip_hdr *iphdr;
+
+  PERF_START;
+
+  LWIP_DEBUGF(IP_DEBUG, ("len %"U16_F" tot_len %"U16_F"\n", p->len, p->tot_len));
+  if (pbuf_header(p, IP_HLEN)) {
+    LWIP_DEBUGF(IP_DEBUG, ("ip_output: not enough room for IP header in pbuf\n"));
+    IP_STATS_INC(ip.err);
+
+    return ERR_BUF;
+  }
+  LWIP_DEBUGF(IP_DEBUG, ("len %"U16_F" tot_len %"U16_F"\n", p->len, p->tot_len));
+
+  iphdr = p->payload;
+
+
+  if (dest != IP_HDRINCL) {
+    LWIP_DEBUGF(IP_DEBUG, ("!IP_HDRLINCL\n"));
+    iphdr->hoplim = ttl;
+    iphdr->nexthdr = proto;
+    iphdr->len = htons(p->tot_len - IP_HLEN);
+    ip_addr_set(&(iphdr->dest), dest);
+
+    iphdr->v = 6;
+
+    if (ip_addr_isany(src)) {
+      ip_addr_set(&(iphdr->src), &(netif->ip_addr));
+    } else {
+      ip_addr_set(&(iphdr->src), src);
+    }
+
+  } else {
+    dest = &(iphdr->dest);
+  }
+
+  IP_STATS_INC(ip.xmit);
+
+  LWIP_DEBUGF(IP_DEBUG, ("ip_output_if: %c%c (len %"U16_F")\n", netif->name[0], netif->name[1], p->tot_len));
+#if IP_DEBUG
+  ip_debug_print(p);
+#endif /* IP_DEBUG */
+
+  PERF_STOP("ip_output_if");
+  return netif->output(netif, p, dest);
+}
+
+/* ip_output:
+ *
+ * Simple interface to ip_output_if. It finds the outgoing network interface and
+ * calls upon ip_output_if to do the actual work.
+ */
+
+err_t
+ip_output(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
+    u8_t ttl, u8_t proto)
+{
+  struct netif *netif;
+  if ((netif = ip_route(dest)) == NULL) {
+    LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to 0x%"X32_F"\n", dest->addr));
+    IP_STATS_INC(ip.rterr);
+    return ERR_RTE;
+  }
+
+  return ip_output_if (p, src, dest, ttl, proto, netif);
+}
+
+#if LWIP_NETIF_HWADDRHINT
+err_t
+ip_output_hinted(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
+          u8_t ttl, u8_t tos, u8_t proto, u8_t *addr_hint)
+{
+  struct netif *netif;
+  err_t err;
+
+  if ((netif = ip_route(dest)) == NULL) {
+    LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to 0x%"X32_F"\n", dest->addr));
+    IP_STATS_INC(ip.rterr);
+    return ERR_RTE;
+  }
+
+  LWIP_NETIF_HWADDRHINT(netif, addr_hint);
+  err = ip_output_if(p, src, dest, ttl, tos, proto, netif);
+  LWIP_NETIF_HWADDRHINT(netif, NULL);
+
+  return err;
+}
+#endif /* LWIP_NETIF_HWADDRHINT*/
+
+#if IP_DEBUG
+void
+ip_debug_print(struct pbuf *p)
+{
+  struct ip_hdr *iphdr = p->payload;
+
+  LWIP_DEBUGF(IP_DEBUG, ("IP header:\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|%2"S16_F" |  %"X16_F"%"X16_F"  |      %"X16_F"%"X16_F"           | (v, traffic class, flow label)\n",
+        iphdr->v,
+        iphdr->tclass1, iphdr->tclass2,
+        iphdr->flow1, iphdr->flow2));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|    %5"U16_F"      | %2"U16_F"  |  %2"U16_F"   | (len, nexthdr, hoplim)\n",
+        ntohs(iphdr->len),
+        iphdr->nexthdr,
+        iphdr->hoplim));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|       %4"X32_F"      |       %4"X32_F"     | (src)\n",
+        (ntohl(iphdr->src.addr[0]) >> 16) & 0xffff,
+        ntohl(iphdr->src.addr[0]) & 0xffff));
+  LWIP_DEBUGF(IP_DEBUG, ("|       %4"X32_F"      |       %4"X32_F"     | (src)\n",
+        (ntohl(iphdr->src.addr[1]) >> 16) & 0xffff,
+        ntohl(iphdr->src.addr[1]) & 0xffff));
+  LWIP_DEBUGF(IP_DEBUG, ("|       %4"X32_F"      |       %4"X32_F"     | (src)\n",
+        (ntohl(iphdr->src.addr[2]) >> 16) & 0xffff,
+        ntohl(iphdr->src.addr[2]) & 0xffff));
+  LWIP_DEBUGF(IP_DEBUG, ("|       %4"X32_F"      |       %4"X32_F"     | (src)\n",
+        (ntohl(iphdr->src.addr[3]) >> 16) & 0xffff,
+        ntohl(iphdr->src.addr[3]) & 0xffff));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+  LWIP_DEBUGF(IP_DEBUG, ("|       %4"X32_F"      |       %4"X32_F"     | (dest)\n",
+        (ntohl(iphdr->dest.addr[0]) >> 16) & 0xffff,
+        ntohl(iphdr->dest.addr[0]) & 0xffff));
+  LWIP_DEBUGF(IP_DEBUG, ("|       %4"X32_F"      |       %4"X32_F"     | (dest)\n",
+        (ntohl(iphdr->dest.addr[1]) >> 16) & 0xffff,
+        ntohl(iphdr->dest.addr[1]) & 0xffff));
+  LWIP_DEBUGF(IP_DEBUG, ("|       %4"X32_F"      |       %4"X32_F"     | (dest)\n",
+        (ntohl(iphdr->dest.addr[2]) >> 16) & 0xffff,
+        ntohl(iphdr->dest.addr[2]) & 0xffff));
+  LWIP_DEBUGF(IP_DEBUG, ("|       %4"X32_F"      |       %4"X32_F"     | (dest)\n",
+        (ntohl(iphdr->dest.addr[3]) >> 16) & 0xffff,
+        ntohl(iphdr->dest.addr[3]) & 0xffff));
+  LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+}
+#endif /* IP_DEBUG */

src/lwip-1.4.1/src/core/ipv6/ip6_addr.c

@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+#include "lwip/ip_addr.h"
+#include "lwip/inet.h"
+
+u8_t
+ip_addr_netcmp(struct ip_addr *addr1, struct ip_addr *addr2,
+                struct ip_addr *mask)
+{
+  return((addr1->addr[0] & mask->addr[0]) == (addr2->addr[0] & mask->addr[0]) &&
+         (addr1->addr[1] & mask->addr[1]) == (addr2->addr[1] & mask->addr[1]) &&
+         (addr1->addr[2] & mask->addr[2]) == (addr2->addr[2] & mask->addr[2]) &&
+         (addr1->addr[3] & mask->addr[3]) == (addr2->addr[3] & mask->addr[3]));
+        
+}
+
+u8_t
+ip_addr_cmp(struct ip_addr *addr1, struct ip_addr *addr2)
+{
+  return(addr1->addr[0] == addr2->addr[0] &&
+         addr1->addr[1] == addr2->addr[1] &&
+         addr1->addr[2] == addr2->addr[2] &&
+         addr1->addr[3] == addr2->addr[3]);
+}
+
+void
+ip_addr_set(struct ip_addr *dest, struct ip_addr *src)
+{
+  SMEMCPY(dest, src, sizeof(struct ip_addr));
+  /*  dest->addr[0] = src->addr[0];
+  dest->addr[1] = src->addr[1];
+  dest->addr[2] = src->addr[2];
+  dest->addr[3] = src->addr[3];*/
+}
+
+u8_t
+ip_addr_isany(struct ip_addr *addr)
+{
+  if (addr == NULL) return 1;
+  return((addr->addr[0] | addr->addr[1] | addr->addr[2] | addr->addr[3]) == 0);
+}

src/lwip-1.4.1/src/core/mem.c

@@ -0,0 +1,659 @@
+/**
+ * @file
+ * Dynamic memory manager
+ *
+ * This is a lightweight replacement for the standard C library malloc().
+ *
+ * If you want to use the standard C library malloc() instead, define
+ * MEM_LIBC_MALLOC to 1 in your lwipopts.h
+ *
+ * To let mem_malloc() use pools (prevents fragmentation and is much faster than
+ * a heap but might waste some memory), define MEM_USE_POOLS to 1, define
+ * MEM_USE_CUSTOM_POOLS to 1 and create a file "lwippools.h" that includes a list
+ * of pools like this (more pools can be added between _START and _END):
+ *
+ * Define three pools with sizes 256, 512, and 1512 bytes
+ * LWIP_MALLOC_MEMPOOL_START
+ * LWIP_MALLOC_MEMPOOL(20, 256)
+ * LWIP_MALLOC_MEMPOOL(10, 512)
+ * LWIP_MALLOC_MEMPOOL(5, 1512)
+ * LWIP_MALLOC_MEMPOOL_END
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *         Simon Goldschmidt
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if !MEM_LIBC_MALLOC /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/sys.h"
+#include "lwip/stats.h"
+#include "lwip/err.h"
+
+#include <string.h>
+
+#if MEM_USE_POOLS
+/* lwIP head implemented with different sized pools */
+
+/**
+ * Allocate memory: determine the smallest pool that is big enough
+ * to contain an element of 'size' and get an element from that pool.
+ *
+ * @param size the size in bytes of the memory needed
+ * @return a pointer to the allocated memory or NULL if the pool is empty
+ */
+void *
+mem_malloc(mem_size_t size)
+{
+  void *ret;
+  struct memp_malloc_helper *element;
+  memp_t poolnr;
+  mem_size_t required_size = size + LWIP_MEM_ALIGN_SIZE(sizeof(struct memp_malloc_helper));
+
+  for (poolnr = MEMP_POOL_FIRST; poolnr <= MEMP_POOL_LAST; poolnr = (memp_t)(poolnr + 1)) {
+#if MEM_USE_POOLS_TRY_BIGGER_POOL
+again:
+#endif /* MEM_USE_POOLS_TRY_BIGGER_POOL */
+    /* is this pool big enough to hold an element of the required size
+       plus a struct memp_malloc_helper that saves the pool this element came from? */
+    if (required_size <= memp_sizes[poolnr]) {
+      break;
+    }
+  }
+  if (poolnr > MEMP_POOL_LAST) {
+    LWIP_ASSERT("mem_malloc(): no pool is that big!", 0);
+    return NULL;
+  }
+  element = (struct memp_malloc_helper*)memp_malloc(poolnr);
+  if (element == NULL) {
+    /* No need to DEBUGF or ASSERT: This error is already
+       taken care of in memp.c */
+#if MEM_USE_POOLS_TRY_BIGGER_POOL
+    /** Try a bigger pool if this one is empty! */
+    if (poolnr < MEMP_POOL_LAST) {
+      poolnr++;
+      goto again;
+    }
+#endif /* MEM_USE_POOLS_TRY_BIGGER_POOL */
+    return NULL;
+  }
+
+  /* save the pool number this element came from */
+  element->poolnr = poolnr;
+  /* and return a pointer to the memory directly after the struct memp_malloc_helper */
+  ret = (u8_t*)element + LWIP_MEM_ALIGN_SIZE(sizeof(struct memp_malloc_helper));
+
+  return ret;
+}
+
+/**
+ * Free memory previously allocated by mem_malloc. Loads the pool number
+ * and calls memp_free with that pool number to put the element back into
+ * its pool
+ *
+ * @param rmem the memory element to free
+ */
+void
+mem_free(void *rmem)
+{
+  struct memp_malloc_helper *hmem;
+
+  LWIP_ASSERT("rmem != NULL", (rmem != NULL));
+  LWIP_ASSERT("rmem == MEM_ALIGN(rmem)", (rmem == LWIP_MEM_ALIGN(rmem)));
+
+  /* get the original struct memp_malloc_helper */
+  hmem = (struct memp_malloc_helper*)(void*)((u8_t*)rmem - LWIP_MEM_ALIGN_SIZE(sizeof(struct memp_malloc_helper)));
+
+  LWIP_ASSERT("hmem != NULL", (hmem != NULL));
+  LWIP_ASSERT("hmem == MEM_ALIGN(hmem)", (hmem == LWIP_MEM_ALIGN(hmem)));
+  LWIP_ASSERT("hmem->poolnr < MEMP_MAX", (hmem->poolnr < MEMP_MAX));
+
+  /* and put it in the pool we saved earlier */
+  memp_free(hmem->poolnr, hmem);
+}
+
+#else /* MEM_USE_POOLS */
+/* lwIP replacement for your libc malloc() */
+
+/**
+ * The heap is made up as a list of structs of this type.
+ * This does not have to be aligned since for getting its size,
+ * we only use the macro SIZEOF_STRUCT_MEM, which automatically alignes.
+ */
+struct mem {
+  /** index (-> ram[next]) of the next struct */
+  mem_size_t next;
+  /** index (-> ram[prev]) of the previous struct */
+  mem_size_t prev;
+  /** 1: this area is used; 0: this area is unused */
+  u8_t used;
+};
+
+/** All allocated blocks will be MIN_SIZE bytes big, at least!
+ * MIN_SIZE can be overridden to suit your needs. Smaller values save space,
+ * larger values could prevent too small blocks to fragment the RAM too much. */
+#ifndef MIN_SIZE
+#define MIN_SIZE             12
+#endif /* MIN_SIZE */
+/* some alignment macros: we define them here for better source code layout */
+#define MIN_SIZE_ALIGNED     LWIP_MEM_ALIGN_SIZE(MIN_SIZE)
+#define SIZEOF_STRUCT_MEM    LWIP_MEM_ALIGN_SIZE(sizeof(struct mem))
+#define MEM_SIZE_ALIGNED     LWIP_MEM_ALIGN_SIZE(MEM_SIZE)
+
+/** If you want to relocate the heap to external memory, simply define
+ * LWIP_RAM_HEAP_POINTER as a void-pointer to that location.
+ * If so, make sure the memory at that location is big enough (see below on
+ * how that space is calculated). */
+#ifndef LWIP_RAM_HEAP_POINTER
+/** the heap. we need one struct mem at the end and some room for alignment */
+u8_t ram_heap[MEM_SIZE_ALIGNED + (2*SIZEOF_STRUCT_MEM) + MEM_ALIGNMENT];
+#define LWIP_RAM_HEAP_POINTER ram_heap
+#endif /* LWIP_RAM_HEAP_POINTER */
+
+/** pointer to the heap (ram_heap): for alignment, ram is now a pointer instead of an array */
+static u8_t *ram;
+/** the last entry, always unused! */
+static struct mem *ram_end;
+/** pointer to the lowest free block, this is used for faster search */
+static struct mem *lfree;
+
+/** concurrent access protection */
+#if !NO_SYS
+static sys_mutex_t mem_mutex;
+#endif
+
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+
+static volatile u8_t mem_free_count;
+
+/* Allow mem_free from other (e.g. interrupt) context */
+#define LWIP_MEM_FREE_DECL_PROTECT()  SYS_ARCH_DECL_PROTECT(lev_free)
+#define LWIP_MEM_FREE_PROTECT()       SYS_ARCH_PROTECT(lev_free)
+#define LWIP_MEM_FREE_UNPROTECT()     SYS_ARCH_UNPROTECT(lev_free)
+#define LWIP_MEM_ALLOC_DECL_PROTECT() SYS_ARCH_DECL_PROTECT(lev_alloc)
+#define LWIP_MEM_ALLOC_PROTECT()      SYS_ARCH_PROTECT(lev_alloc)
+#define LWIP_MEM_ALLOC_UNPROTECT()    SYS_ARCH_UNPROTECT(lev_alloc)
+
+#else /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+
+/* Protect the heap only by using a semaphore */
+#define LWIP_MEM_FREE_DECL_PROTECT()
+#define LWIP_MEM_FREE_PROTECT()    sys_mutex_lock(&mem_mutex)
+#define LWIP_MEM_FREE_UNPROTECT()  sys_mutex_unlock(&mem_mutex)
+/* mem_malloc is protected using semaphore AND LWIP_MEM_ALLOC_PROTECT */
+#define LWIP_MEM_ALLOC_DECL_PROTECT()
+#define LWIP_MEM_ALLOC_PROTECT()
+#define LWIP_MEM_ALLOC_UNPROTECT()
+
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+
+
+/**
+ * "Plug holes" by combining adjacent empty struct mems.
+ * After this function is through, there should not exist
+ * one empty struct mem pointing to another empty struct mem.
+ *
+ * @param mem this points to a struct mem which just has been freed
+ * @internal this function is only called by mem_free() and mem_trim()
+ *
+ * This assumes access to the heap is protected by the calling function
+ * already.
+ */
+static void
+plug_holes(struct mem *mem)
+{
+  struct mem *nmem;
+  struct mem *pmem;
+
+  LWIP_ASSERT("plug_holes: mem >= ram", (u8_t *)mem >= ram);
+  LWIP_ASSERT("plug_holes: mem < ram_end", (u8_t *)mem < (u8_t *)ram_end);
+  LWIP_ASSERT("plug_holes: mem->used == 0", mem->used == 0);
+
+  /* plug hole forward */
+  LWIP_ASSERT("plug_holes: mem->next <= MEM_SIZE_ALIGNED", mem->next <= MEM_SIZE_ALIGNED);
+
+  nmem = (struct mem *)(void *)&ram[mem->next];
+  if (mem != nmem && nmem->used == 0 && (u8_t *)nmem != (u8_t *)ram_end) {
+    /* if mem->next is unused and not end of ram, combine mem and mem->next */
+    if (lfree == nmem) {
+      lfree = mem;
+    }
+    mem->next = nmem->next;
+    ((struct mem *)(void *)&ram[nmem->next])->prev = (mem_size_t)((u8_t *)mem - ram);
+  }
+
+  /* plug hole backward */
+  pmem = (struct mem *)(void *)&ram[mem->prev];
+  if (pmem != mem && pmem->used == 0) {
+    /* if mem->prev is unused, combine mem and mem->prev */
+    if (lfree == mem) {
+      lfree = pmem;
+    }
+    pmem->next = mem->next;
+    ((struct mem *)(void *)&ram[mem->next])->prev = (mem_size_t)((u8_t *)pmem - ram);
+  }
+}
+
+/**
+ * Zero the heap and initialize start, end and lowest-free
+ */
+void
+mem_init(void)
+{
+  struct mem *mem;
+
+  LWIP_ASSERT("Sanity check alignment",
+    (SIZEOF_STRUCT_MEM & (MEM_ALIGNMENT-1)) == 0);
+
+  /* align the heap */
+  ram = (u8_t *)LWIP_MEM_ALIGN(LWIP_RAM_HEAP_POINTER);
+  /* initialize the start of the heap */
+  mem = (struct mem *)(void *)ram;
+  mem->next = MEM_SIZE_ALIGNED;
+  mem->prev = 0;
+  mem->used = 0;
+  /* initialize the end of the heap */
+  ram_end = (struct mem *)(void *)&ram[MEM_SIZE_ALIGNED];
+  ram_end->used = 1;
+  ram_end->next = MEM_SIZE_ALIGNED;
+  ram_end->prev = MEM_SIZE_ALIGNED;
+
+  /* initialize the lowest-free pointer to the start of the heap */
+  lfree = (struct mem *)(void *)ram;
+
+  MEM_STATS_AVAIL(avail, MEM_SIZE_ALIGNED);
+
+  if(sys_mutex_new(&mem_mutex) != ERR_OK) {
+    LWIP_ASSERT("failed to create mem_mutex", 0);
+  }
+}
+
+/**
+ * Put a struct mem back on the heap
+ *
+ * @param rmem is the data portion of a struct mem as returned by a previous
+ *             call to mem_malloc()
+ */
+void
+mem_free(void *rmem)
+{
+  struct mem *mem;
+  LWIP_MEM_FREE_DECL_PROTECT();
+
+  if (rmem == NULL) {
+    LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("mem_free(p == NULL) was called.\n"));
+    return;
+  }
+  LWIP_ASSERT("mem_free: sanity check alignment", (((mem_ptr_t)rmem) & (MEM_ALIGNMENT-1)) == 0);
+
+  LWIP_ASSERT("mem_free: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
+    (u8_t *)rmem < (u8_t *)ram_end);
+
+  if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
+    SYS_ARCH_DECL_PROTECT(lev);
+    LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SEVERE, ("mem_free: illegal memory\n"));
+    /* protect mem stats from concurrent access */
+    SYS_ARCH_PROTECT(lev);
+    MEM_STATS_INC(illegal);
+    SYS_ARCH_UNPROTECT(lev);
+    return;
+  }
+  /* protect the heap from concurrent access */
+  LWIP_MEM_FREE_PROTECT();
+  /* Get the corresponding struct mem ... */
+  mem = (struct mem *)(void *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
+  /* ... which has to be in a used state ... */
+  LWIP_ASSERT("mem_free: mem->used", mem->used);
+  /* ... and is now unused. */
+  mem->used = 0;
+
+  if (mem < lfree) {
+    /* the newly freed struct is now the lowest */
+    lfree = mem;
+  }
+
+  MEM_STATS_DEC_USED(used, mem->next - (mem_size_t)(((u8_t *)mem - ram)));
+
+  /* finally, see if prev or next are free also */
+  plug_holes(mem);
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+  mem_free_count = 1;
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+  LWIP_MEM_FREE_UNPROTECT();
+}
+
+/**
+ * Shrink memory returned by mem_malloc().
+ *
+ * @param rmem pointer to memory allocated by mem_malloc the is to be shrinked
+ * @param newsize required size after shrinking (needs to be smaller than or
+ *                equal to the previous size)
+ * @return for compatibility reasons: is always == rmem, at the moment
+ *         or NULL if newsize is > old size, in which case rmem is NOT touched
+ *         or freed!
+ */
+void *
+mem_trim(void *rmem, mem_size_t newsize)
+{
+  mem_size_t size;
+  mem_size_t ptr, ptr2;
+  struct mem *mem, *mem2;
+  /* use the FREE_PROTECT here: it protects with sem OR SYS_ARCH_PROTECT */
+  LWIP_MEM_FREE_DECL_PROTECT();
+
+  /* Expand the size of the allocated memory region so that we can
+     adjust for alignment. */
+  newsize = LWIP_MEM_ALIGN_SIZE(newsize);
+
+  if(newsize < MIN_SIZE_ALIGNED) {
+    /* every data block must be at least MIN_SIZE_ALIGNED long */
+    newsize = MIN_SIZE_ALIGNED;
+  }
+
+  if (newsize > MEM_SIZE_ALIGNED) {
+    return NULL;
+  }
+
+  LWIP_ASSERT("mem_trim: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
+   (u8_t *)rmem < (u8_t *)ram_end);
+
+  if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
+    SYS_ARCH_DECL_PROTECT(lev);
+    LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SEVERE, ("mem_trim: illegal memory\n"));
+    /* protect mem stats from concurrent access */
+    SYS_ARCH_PROTECT(lev);
+    MEM_STATS_INC(illegal);
+    SYS_ARCH_UNPROTECT(lev);
+    return rmem;
+  }
+  /* Get the corresponding struct mem ... */
+  mem = (struct mem *)(void *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
+  /* ... and its offset pointer */
+  ptr = (mem_size_t)((u8_t *)mem - ram);
+
+  size = mem->next - ptr - SIZEOF_STRUCT_MEM;
+  LWIP_ASSERT("mem_trim can only shrink memory", newsize <= size);
+  if (newsize > size) {
+    /* not supported */
+    return NULL;
+  }
+  if (newsize == size) {
+    /* No change in size, simply return */
+    return rmem;
+  }
+
+  /* protect the heap from concurrent access */
+  LWIP_MEM_FREE_PROTECT();
+
+  mem2 = (struct mem *)(void *)&ram[mem->next];
+  if(mem2->used == 0) {
+    /* The next struct is unused, we can simply move it at little */
+    mem_size_t next;
+    /* remember the old next pointer */
+    next = mem2->next;
+    /* create new struct mem which is moved directly after the shrinked mem */
+    ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
+    if (lfree == mem2) {
+      lfree = (struct mem *)(void *)&ram[ptr2];
+    }
+    mem2 = (struct mem *)(void *)&ram[ptr2];
+    mem2->used = 0;
+    /* restore the next pointer */
+    mem2->next = next;
+    /* link it back to mem */
+    mem2->prev = ptr;
+    /* link mem to it */
+    mem->next = ptr2;
+    /* last thing to restore linked list: as we have moved mem2,
+     * let 'mem2->next->prev' point to mem2 again. but only if mem2->next is not
+     * the end of the heap */
+    if (mem2->next != MEM_SIZE_ALIGNED) {
+      ((struct mem *)(void *)&ram[mem2->next])->prev = ptr2;
+    }
+    MEM_STATS_DEC_USED(used, (size - newsize));
+    /* no need to plug holes, we've already done that */
+  } else if (newsize + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED <= size) {
+    /* Next struct is used but there's room for another struct mem with
+     * at least MIN_SIZE_ALIGNED of data.
+     * Old size ('size') must be big enough to contain at least 'newsize' plus a struct mem
+     * ('SIZEOF_STRUCT_MEM') with some data ('MIN_SIZE_ALIGNED').
+     * @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
+     *       region that couldn't hold data, but when mem->next gets freed,
+     *       the 2 regions would be combined, resulting in more free memory */
+    ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
+    mem2 = (struct mem *)(void *)&ram[ptr2];
+    if (mem2 < lfree) {
+      lfree = mem2;
+    }
+    mem2->used = 0;
+    mem2->next = mem->next;
+    mem2->prev = ptr;
+    mem->next = ptr2;
+    if (mem2->next != MEM_SIZE_ALIGNED) {
+      ((struct mem *)(void *)&ram[mem2->next])->prev = ptr2;
+    }
+    MEM_STATS_DEC_USED(used, (size - newsize));
+    /* the original mem->next is used, so no need to plug holes! */
+  }
+  /* else {
+    next struct mem is used but size between mem and mem2 is not big enough
+    to create another struct mem
+    -> don't do anyhting. 
+    -> the remaining space stays unused since it is too small
+  } */
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+  mem_free_count = 1;
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+  LWIP_MEM_FREE_UNPROTECT();
+  return rmem;
+}
+
+/**
+ * Adam's mem_malloc() plus solution for bug #17922
+ * Allocate a block of memory with a minimum of 'size' bytes.
+ *
+ * @param size is the minimum size of the requested block in bytes.
+ * @return pointer to allocated memory or NULL if no free memory was found.
+ *
+ * Note that the returned value will always be aligned (as defined by MEM_ALIGNMENT).
+ */
+void *
+mem_malloc(mem_size_t size)
+{
+  mem_size_t ptr, ptr2;
+  struct mem *mem, *mem2;
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+  u8_t local_mem_free_count = 0;
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+  LWIP_MEM_ALLOC_DECL_PROTECT();
+
+  if (size == 0) {
+    return NULL;
+  }
+
+  /* Expand the size of the allocated memory region so that we can
+     adjust for alignment. */
+  size = LWIP_MEM_ALIGN_SIZE(size);
+
+  if(size < MIN_SIZE_ALIGNED) {
+    /* every data block must be at least MIN_SIZE_ALIGNED long */
+    size = MIN_SIZE_ALIGNED;
+  }
+
+  if (size > MEM_SIZE_ALIGNED) {
+    return NULL;
+  }
+
+  /* protect the heap from concurrent access */
+  sys_mutex_lock(&mem_mutex);
+  LWIP_MEM_ALLOC_PROTECT();
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+  /* run as long as a mem_free disturbed mem_malloc or mem_trim */
+  do {
+    local_mem_free_count = 0;
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+
+    /* Scan through the heap searching for a free block that is big enough,
+     * beginning with the lowest free block.
+     */
+    for (ptr = (mem_size_t)((u8_t *)lfree - ram); ptr < MEM_SIZE_ALIGNED - size;
+         ptr = ((struct mem *)(void *)&ram[ptr])->next) {
+      mem = (struct mem *)(void *)&ram[ptr];
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+      mem_free_count = 0;
+      LWIP_MEM_ALLOC_UNPROTECT();
+      /* allow mem_free or mem_trim to run */
+      LWIP_MEM_ALLOC_PROTECT();
+      if (mem_free_count != 0) {
+        /* If mem_free or mem_trim have run, we have to restart since they
+           could have altered our current struct mem. */
+        local_mem_free_count = 1;
+        break;
+      }
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+
+      if ((!mem->used) &&
+          (mem->next - (ptr + SIZEOF_STRUCT_MEM)) >= size) {
+        /* mem is not used and at least perfect fit is possible:
+         * mem->next - (ptr + SIZEOF_STRUCT_MEM) gives us the 'user data size' of mem */
+
+        if (mem->next - (ptr + SIZEOF_STRUCT_MEM) >= (size + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED)) {
+          /* (in addition to the above, we test if another struct mem (SIZEOF_STRUCT_MEM) containing
+           * at least MIN_SIZE_ALIGNED of data also fits in the 'user data space' of 'mem')
+           * -> split large block, create empty remainder,
+           * remainder must be large enough to contain MIN_SIZE_ALIGNED data: if
+           * mem->next - (ptr + (2*SIZEOF_STRUCT_MEM)) == size,
+           * struct mem would fit in but no data between mem2 and mem2->next
+           * @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
+           *       region that couldn't hold data, but when mem->next gets freed,
+           *       the 2 regions would be combined, resulting in more free memory
+           */
+          ptr2 = ptr + SIZEOF_STRUCT_MEM + size;
+          /* create mem2 struct */
+          mem2 = (struct mem *)(void *)&ram[ptr2];
+          mem2->used = 0;
+          mem2->next = mem->next;
+          mem2->prev = ptr;
+          /* and insert it between mem and mem->next */
+          mem->next = ptr2;
+          mem->used = 1;
+
+          if (mem2->next != MEM_SIZE_ALIGNED) {
+            ((struct mem *)(void *)&ram[mem2->next])->prev = ptr2;
+          }
+          MEM_STATS_INC_USED(used, (size + SIZEOF_STRUCT_MEM));
+        } else {
+          /* (a mem2 struct does no fit into the user data space of mem and mem->next will always
+           * be used at this point: if not we have 2 unused structs in a row, plug_holes should have
+           * take care of this).
+           * -> near fit or excact fit: do not split, no mem2 creation
+           * also can't move mem->next directly behind mem, since mem->next
+           * will always be used at this point!
+           */
+          mem->used = 1;
+          MEM_STATS_INC_USED(used, mem->next - (mem_size_t)((u8_t *)mem - ram));
+        }
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+mem_malloc_adjust_lfree:
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+        if (mem == lfree) {
+          struct mem *cur = lfree;
+          /* Find next free block after mem and update lowest free pointer */
+          while (cur->used && cur != ram_end) {
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+            mem_free_count = 0;
+            LWIP_MEM_ALLOC_UNPROTECT();
+            /* prevent high interrupt latency... */
+            LWIP_MEM_ALLOC_PROTECT();
+            if (mem_free_count != 0) {
+              /* If mem_free or mem_trim have run, we have to restart since they
+                 could have altered our current struct mem or lfree. */
+              goto mem_malloc_adjust_lfree;
+            }
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+            cur = (struct mem *)(void *)&ram[cur->next];
+          }
+          lfree = cur;
+          LWIP_ASSERT("mem_malloc: !lfree->used", ((lfree == ram_end) || (!lfree->used)));
+        }
+        LWIP_MEM_ALLOC_UNPROTECT();
+        sys_mutex_unlock(&mem_mutex);
+        LWIP_ASSERT("mem_malloc: allocated memory not above ram_end.",
+         (mem_ptr_t)mem + SIZEOF_STRUCT_MEM + size <= (mem_ptr_t)ram_end);
+        LWIP_ASSERT("mem_malloc: allocated memory properly aligned.",
+         ((mem_ptr_t)mem + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT == 0);
+        LWIP_ASSERT("mem_malloc: sanity check alignment",
+          (((mem_ptr_t)mem) & (MEM_ALIGNMENT-1)) == 0);
+
+        return (u8_t *)mem + SIZEOF_STRUCT_MEM;
+      }
+    }
+#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+    /* if we got interrupted by a mem_free, try again */
+  } while(local_mem_free_count != 0);
+#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
+  LWIP_DEBUGF(MEM_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("mem_malloc: could not allocate %"S16_F" bytes\n", (s16_t)size));
+  MEM_STATS_INC(err);
+  LWIP_MEM_ALLOC_UNPROTECT();
+  sys_mutex_unlock(&mem_mutex);
+  return NULL;
+}
+
+#endif /* MEM_USE_POOLS */
+/**
+ * Contiguously allocates enough space for count objects that are size bytes
+ * of memory each and returns a pointer to the allocated memory.
+ *
+ * The allocated memory is filled with bytes of value zero.
+ *
+ * @param count number of objects to allocate
+ * @param size size of the objects to allocate
+ * @return pointer to allocated memory / NULL pointer if there is an error
+ */
+void *mem_calloc(mem_size_t count, mem_size_t size)
+{
+  void *p;
+
+  /* allocate 'count' objects of size 'size' */
+  p = mem_malloc(count * size);
+  if (p) {
+    /* zero the memory */
+    memset(p, 0, count * size);
+  }
+  return p;
+}
+
+#endif /* !MEM_LIBC_MALLOC */

src/lwip-1.4.1/src/core/memp.c

@@ -0,0 +1,470 @@
+/**
+ * @file
+ * Dynamic pool memory manager
+ *
+ * lwIP has dedicated pools for many structures (netconn, protocol control blocks,
+ * packet buffers, ...). All these pools are managed here.
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved. 
+ * 
+ * Redistribution and use in source and binary forms, with or without modification, 
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ * 
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/memp.h"
+#include "lwip/pbuf.h"
+#include "lwip/udp.h"
+#include "lwip/raw.h"
+#include "lwip/tcp_impl.h"
+#include "lwip/igmp.h"
+#include "lwip/api.h"
+#include "lwip/api_msg.h"
+#include "lwip/tcpip.h"
+#include "lwip/sys.h"
+#include "lwip/timers.h"
+#include "lwip/stats.h"
+#include "netif/etharp.h"
+#include "lwip/ip_frag.h"
+#include "lwip/snmp_structs.h"
+#include "lwip/snmp_msg.h"
+#include "lwip/dns.h"
+#include "netif/ppp_oe.h"
+
+#include <string.h>
+
+#if !MEMP_MEM_MALLOC /* don't build if not configured for use in lwipopts.h */
+
+struct memp {
+  struct memp *next;
+#if MEMP_OVERFLOW_CHECK
+  const char *file;
+  int line;
+#endif /* MEMP_OVERFLOW_CHECK */
+};
+
+#if MEMP_OVERFLOW_CHECK
+/* if MEMP_OVERFLOW_CHECK is turned on, we reserve some bytes at the beginning
+ * and at the end of each element, initialize them as 0xcd and check
+ * them later. */
+/* If MEMP_OVERFLOW_CHECK is >= 2, on every call to memp_malloc or memp_free,
+ * every single element in each pool is checked!
+ * This is VERY SLOW but also very helpful. */
+/* MEMP_SANITY_REGION_BEFORE and MEMP_SANITY_REGION_AFTER can be overridden in
+ * lwipopts.h to change the amount reserved for checking. */
+#ifndef MEMP_SANITY_REGION_BEFORE
+#define MEMP_SANITY_REGION_BEFORE  16
+#endif /* MEMP_SANITY_REGION_BEFORE*/
+#if MEMP_SANITY_REGION_BEFORE > 0
+#define MEMP_SANITY_REGION_BEFORE_ALIGNED    LWIP_MEM_ALIGN_SIZE(MEMP_SANITY_REGION_BEFORE)
+#else
+#define MEMP_SANITY_REGION_BEFORE_ALIGNED    0
+#endif /* MEMP_SANITY_REGION_BEFORE*/
+#ifndef MEMP_SANITY_REGION_AFTER
+#define MEMP_SANITY_REGION_AFTER   16
+#endif /* MEMP_SANITY_REGION_AFTER*/
+#if MEMP_SANITY_REGION_AFTER > 0
+#define MEMP_SANITY_REGION_AFTER_ALIGNED     LWIP_MEM_ALIGN_SIZE(MEMP_SANITY_REGION_AFTER)
+#else
+#define MEMP_SANITY_REGION_AFTER_ALIGNED     0
+#endif /* MEMP_SANITY_REGION_AFTER*/
+
+/* MEMP_SIZE: save space for struct memp and for sanity check */
+#define MEMP_SIZE          (LWIP_MEM_ALIGN_SIZE(sizeof(struct memp)) + MEMP_SANITY_REGION_BEFORE_ALIGNED)
+#define MEMP_ALIGN_SIZE(x) (LWIP_MEM_ALIGN_SIZE(x) + MEMP_SANITY_REGION_AFTER_ALIGNED)
+
+#else /* MEMP_OVERFLOW_CHECK */
+
+/* No sanity checks
+ * We don't need to preserve the struct memp while not allocated, so we
+ * can save a little space and set MEMP_SIZE to 0.
+ */
+#define MEMP_SIZE           0
+#define MEMP_ALIGN_SIZE(x) (LWIP_MEM_ALIGN_SIZE(x))
+
+#endif /* MEMP_OVERFLOW_CHECK */
+
+/** This array holds the first free element of each pool.
+ *  Elements form a linked list. */
+static struct memp *memp_tab[MEMP_MAX];
+
+#else /* MEMP_MEM_MALLOC */
+
+#define MEMP_ALIGN_SIZE(x) (LWIP_MEM_ALIGN_SIZE(x))
+
+#endif /* MEMP_MEM_MALLOC */
+
+/** This array holds the element sizes of each pool. */
+#if !MEM_USE_POOLS && !MEMP_MEM_MALLOC
+static
+#endif
+const u16_t memp_sizes[MEMP_MAX] = {
+#define LWIP_MEMPOOL(name,num,size,desc)  LWIP_MEM_ALIGN_SIZE(size),
+#include "lwip/memp_std.h"
+};
+
+#if !MEMP_MEM_MALLOC /* don't build if not configured for use in lwipopts.h */
+
+/** This array holds the number of elements in each pool. */
+static const u16_t memp_num[MEMP_MAX] = {
+#define LWIP_MEMPOOL(name,num,size,desc)  (num),
+#include "lwip/memp_std.h"
+};
+
+/** This array holds a textual description of each pool. */
+#ifdef LWIP_DEBUG
+static const char *memp_desc[MEMP_MAX] = {
+#define LWIP_MEMPOOL(name,num,size,desc)  (desc),
+#include "lwip/memp_std.h"
+};
+#endif /* LWIP_DEBUG */
+
+#if MEMP_SEPARATE_POOLS
+
+/** This creates each memory pool. These are named memp_memory_XXX_base (where
+ * XXX is the name of the pool defined in memp_std.h).
+ * To relocate a pool, declare it as extern in cc.h. Example for GCC:
+ *   extern u8_t __attribute__((section(".onchip_mem"))) memp_memory_UDP_PCB_base[];
+ */
+#define LWIP_MEMPOOL(name,num,size,desc) u8_t memp_memory_ ## name ## _base \
+  [((num) * (MEMP_SIZE + MEMP_ALIGN_SIZE(size)))];   
+#include "lwip/memp_std.h"
+
+/** This array holds the base of each memory pool. */
+static u8_t *const memp_bases[] = { 
+#define LWIP_MEMPOOL(name,num,size,desc) memp_memory_ ## name ## _base,   
+#include "lwip/memp_std.h"
+};
+
+#else /* MEMP_SEPARATE_POOLS */
+
+/** This is the actual memory used by the pools (all pools in one big block). */
+static u8_t memp_memory[MEM_ALIGNMENT - 1 
+#define LWIP_MEMPOOL(name,num,size,desc) + ( (num) * (MEMP_SIZE + MEMP_ALIGN_SIZE(size) ) )
+#include "lwip/memp_std.h"
+];
+
+#endif /* MEMP_SEPARATE_POOLS */
+
+#if MEMP_SANITY_CHECK
+/**
+ * Check that memp-lists don't form a circle, using "Floyd's cycle-finding algorithm".
+ */
+static int
+memp_sanity(void)
+{
+  s16_t i;
+  struct memp *t, *h;
+
+  for (i = 0; i < MEMP_MAX; i++) {
+    t = memp_tab[i];
+    if(t != NULL) {
+      for (h = t->next; (t != NULL) && (h != NULL); t = t->next,
+        h = (((h->next != NULL) && (h->next->next != NULL)) ? h->next->next : NULL)) {
+        if (t == h) {
+          return 0;
+        }
+      }
+    }
+  }
+  return 1;
+}
+#endif /* MEMP_SANITY_CHECK*/
+#if MEMP_OVERFLOW_CHECK
+#if defined(LWIP_DEBUG) && MEMP_STATS
+static const char * memp_overflow_names[] = {
+#define LWIP_MEMPOOL(name,num,size,desc) "/"desc,
+#include "lwip/memp_std.h"
+  };
+#endif
+
+/**
+ * Check if a memp element was victim of an overflow
+ * (e.g. the restricted area after it has been altered)
+ *
+ * @param p the memp element to check
+ * @param memp_type the pool p comes from
+ */
+static void
+memp_overflow_check_element_overflow(struct memp *p, u16_t memp_type)
+{
+  u16_t k;
+  u8_t *m;
+#if MEMP_SANITY_REGION_AFTER_ALIGNED > 0
+  m = (u8_t*)p + MEMP_SIZE + memp_sizes[memp_type];
+  for (k = 0; k < MEMP_SANITY_REGION_AFTER_ALIGNED; k++) {
+    if (m[k] != 0xcd) {
+      char errstr[128] = "detected memp overflow in pool ";
+      char digit[] = "0";
+      if(memp_type >= 10) {
+        digit[0] = '0' + (memp_type/10);
+        strcat(errstr, digit);
+      }
+      digit[0] = '0' + (memp_type%10);
+      strcat(errstr, digit);
+#if defined(LWIP_DEBUG) && MEMP_STATS
+      strcat(errstr, memp_overflow_names[memp_type]);
+#endif
+      LWIP_ASSERT(errstr, 0);
+    }
+  }
+#endif
+}
+
+/**
+ * Check if a memp element was victim of an underflow
+ * (e.g. the restricted area before it has been altered)
+ *
+ * @param p the memp element to check
+ * @param memp_type the pool p comes from
+ */
+static void
+memp_overflow_check_element_underflow(struct memp *p, u16_t memp_type)
+{
+  u16_t k;
+  u8_t *m;
+#if MEMP_SANITY_REGION_BEFORE_ALIGNED > 0
+  m = (u8_t*)p + MEMP_SIZE - MEMP_SANITY_REGION_BEFORE_ALIGNED;
+  for (k = 0; k < MEMP_SANITY_REGION_BEFORE_ALIGNED; k++) {
+    if (m[k] != 0xcd) {
+      char errstr[128] = "detected memp underflow in pool ";
+      char digit[] = "0";
+      if(memp_type >= 10) {
+        digit[0] = '0' + (memp_type/10);
+        strcat(errstr, digit);
+      }
+      digit[0] = '0' + (memp_type%10);
+      strcat(errstr, digit);
+#if defined(LWIP_DEBUG) && MEMP_STATS
+      strcat(errstr, memp_overflow_names[memp_type]);
+#endif
+      LWIP_ASSERT(errstr, 0);
+    }
+  }
+#endif
+}
+
+/**
+ * Do an overflow check for all elements in every pool.
+ *
+ * @see memp_overflow_check_element for a description of the check
+ */
+static void
+memp_overflow_check_all(void)
+{
+  u16_t i, j;
+  struct memp *p;
+
+  p = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
+  for (i = 0; i < MEMP_MAX; ++i) {
+    p = p;
+    for (j = 0; j < memp_num[i]; ++j) {
+      memp_overflow_check_element_overflow(p, i);
+      p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i] + MEMP_SANITY_REGION_AFTER_ALIGNED);
+    }
+  }
+  p = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
+  for (i = 0; i < MEMP_MAX; ++i) {
+    p = p;
+    for (j = 0; j < memp_num[i]; ++j) {
+      memp_overflow_check_element_underflow(p, i);
+      p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i] + MEMP_SANITY_REGION_AFTER_ALIGNED);
+    }
+  }
+}
+
+/**
+ * Initialize the restricted areas of all memp elements in every pool.
+ */
+static void
+memp_overflow_init(void)
+{
+  u16_t i, j;
+  struct memp *p;
+  u8_t *m;
+
+  p = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
+  for (i = 0; i < MEMP_MAX; ++i) {
+    p = p;
+    for (j = 0; j < memp_num[i]; ++j) {
+#if MEMP_SANITY_REGION_BEFORE_ALIGNED > 0
+      m = (u8_t*)p + MEMP_SIZE - MEMP_SANITY_REGION_BEFORE_ALIGNED;
+      memset(m, 0xcd, MEMP_SANITY_REGION_BEFORE_ALIGNED);
+#endif
+#if MEMP_SANITY_REGION_AFTER_ALIGNED > 0
+      m = (u8_t*)p + MEMP_SIZE + memp_sizes[i];
+      memset(m, 0xcd, MEMP_SANITY_REGION_AFTER_ALIGNED);
+#endif
+      p = (struct memp*)((u8_t*)p + MEMP_SIZE + memp_sizes[i] + MEMP_SANITY_REGION_AFTER_ALIGNED);
+    }
+  }
+}
+#endif /* MEMP_OVERFLOW_CHECK */
+
+/**
+ * Initialize this module.
+ * 
+ * Carves out memp_memory into linked lists for each pool-type.
+ */
+void
+memp_init(void)
+{
+  struct memp *memp;
+  u16_t i, j;
+
+  for (i = 0; i < MEMP_MAX; ++i) {
+    MEMP_STATS_AVAIL(used, i, 0);
+    MEMP_STATS_AVAIL(max, i, 0);
+    MEMP_STATS_AVAIL(err, i, 0);
+    MEMP_STATS_AVAIL(avail, i, memp_num[i]);
+  }
+
+#if !MEMP_SEPARATE_POOLS
+  memp = (struct memp *)LWIP_MEM_ALIGN(memp_memory);
+#endif /* !MEMP_SEPARATE_POOLS */
+  /* for every pool: */
+  for (i = 0; i < MEMP_MAX; ++i) {
+    memp_tab[i] = NULL;
+#if MEMP_SEPARATE_POOLS
+    memp = (struct memp*)memp_bases[i];
+#endif /* MEMP_SEPARATE_POOLS */
+    /* create a linked list of memp elements */
+    for (j = 0; j < memp_num[i]; ++j) {
+      memp->next = memp_tab[i];
+      memp_tab[i] = memp;
+      memp = (struct memp *)(void *)((u8_t *)memp + MEMP_SIZE + memp_sizes[i]
+#if MEMP_OVERFLOW_CHECK
+        + MEMP_SANITY_REGION_AFTER_ALIGNED
+#endif
+      );
+    }
+  }
+#if MEMP_OVERFLOW_CHECK
+  memp_overflow_init();
+  /* check everything a first time to see if it worked */
+  memp_overflow_check_all();
+#endif /* MEMP_OVERFLOW_CHECK */
+}
+
+/**
+ * Get an element from a specific pool.
+ *
+ * @param type the pool to get an element from
+ *
+ * the debug version has two more parameters:
+ * @param file file name calling this function
+ * @param line number of line where this function is called
+ *
+ * @return a pointer to the allocated memory or a NULL pointer on error
+ */
+void *
+#if !MEMP_OVERFLOW_CHECK
+memp_malloc(memp_t type)
+#else
+memp_malloc_fn(memp_t type, const char* file, const int line)
+#endif
+{
+  struct memp *memp;
+  SYS_ARCH_DECL_PROTECT(old_level);
+ 
+  LWIP_ERROR("memp_malloc: type < MEMP_MAX", (type < MEMP_MAX), return NULL;);
+
+  SYS_ARCH_PROTECT(old_level);
+#if MEMP_OVERFLOW_CHECK >= 2
+  memp_overflow_check_all();
+#endif /* MEMP_OVERFLOW_CHECK >= 2 */
+
+  memp = memp_tab[type];
+  
+  if (memp != NULL) {
+    memp_tab[type] = memp->next;
+#if MEMP_OVERFLOW_CHECK
+    memp->next = NULL;
+    memp->file = file;
+    memp->line = line;
+#endif /* MEMP_OVERFLOW_CHECK */
+    MEMP_STATS_INC_USED(used, type);
+    LWIP_ASSERT("memp_malloc: memp properly aligned",
+                ((mem_ptr_t)memp % MEM_ALIGNMENT) == 0);
+    memp = (struct memp*)(void *)((u8_t*)memp + MEMP_SIZE);
+  } else {
+    LWIP_DEBUGF(MEMP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("memp_malloc: out of memory in pool %s\n", memp_desc[type]));
+    MEMP_STATS_INC(err, type);
+  }
+
+  SYS_ARCH_UNPROTECT(old_level);
+
+  return memp;
+}
+
+/**
+ * Put an element back into its pool.
+ *
+ * @param type the pool where to put mem
+ * @param mem the memp element to free
+ */
+void
+memp_free(memp_t type, void *mem)
+{
+  struct memp *memp;
+  SYS_ARCH_DECL_PROTECT(old_level);
+
+  if (mem == NULL) {
+    return;
+  }
+  LWIP_ASSERT("memp_free: mem properly aligned",
+                ((mem_ptr_t)mem % MEM_ALIGNMENT) == 0);
+
+  memp = (struct memp *)(void *)((u8_t*)mem - MEMP_SIZE);
+
+  SYS_ARCH_PROTECT(old_level);
+#if MEMP_OVERFLOW_CHECK
+#if MEMP_OVERFLOW_CHECK >= 2
+  memp_overflow_check_all();
+#else
+  memp_overflow_check_element_overflow(memp, type);
+  memp_overflow_check_element_underflow(memp, type);
+#endif /* MEMP_OVERFLOW_CHECK >= 2 */
+#endif /* MEMP_OVERFLOW_CHECK */
+
+  MEMP_STATS_DEC(used, type); 
+  
+  memp->next = memp_tab[type]; 
+  memp_tab[type] = memp;
+
+#if MEMP_SANITY_CHECK
+  LWIP_ASSERT("memp sanity", memp_sanity());
+#endif /* MEMP_SANITY_CHECK */
+
+  SYS_ARCH_UNPROTECT(old_level);
+}
+
+#endif /* MEMP_MEM_MALLOC */

src/lwip-1.4.1/src/core/netif.c

@@ -0,0 +1,774 @@
+/**
+ * @file
+ * lwIP network interface abstraction
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#include "lwip/def.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+#include "lwip/tcp_impl.h"
+#include "lwip/snmp.h"
+#include "lwip/igmp.h"
+#include "netif/etharp.h"
+#include "lwip/stats.h"
+#if ENABLE_LOOPBACK
+#include "lwip/sys.h"
+#if LWIP_NETIF_LOOPBACK_MULTITHREADING
+#include "lwip/tcpip.h"
+#endif /* LWIP_NETIF_LOOPBACK_MULTITHREADING */
+#endif /* ENABLE_LOOPBACK */
+
+#if LWIP_AUTOIP
+#include "lwip/autoip.h"
+#endif /* LWIP_AUTOIP */
+#if LWIP_DHCP
+#include "lwip/dhcp.h"
+#endif /* LWIP_DHCP */
+
+#if LWIP_NETIF_STATUS_CALLBACK
+#define NETIF_STATUS_CALLBACK(n) do{ if (n->status_callback) { (n->status_callback)(n); }}while(0)
+#else
+#define NETIF_STATUS_CALLBACK(n)
+#endif /* LWIP_NETIF_STATUS_CALLBACK */ 
+
+#if LWIP_NETIF_LINK_CALLBACK
+#define NETIF_LINK_CALLBACK(n) do{ if (n->link_callback) { (n->link_callback)(n); }}while(0)
+#else
+#define NETIF_LINK_CALLBACK(n)
+#endif /* LWIP_NETIF_LINK_CALLBACK */ 
+
+struct netif *netif_list;
+struct netif *netif_default;
+
+static u8_t netif_num;
+
+#if LWIP_HAVE_LOOPIF
+static struct netif loop_netif;
+
+/**
+ * Initialize a lwip network interface structure for a loopback interface
+ *
+ * @param netif the lwip network interface structure for this loopif
+ * @return ERR_OK if the loopif is initialized
+ *         ERR_MEM if private data couldn't be allocated
+ */
+static err_t
+netif_loopif_init(struct netif *netif)
+{
+  /* initialize the snmp variables and counters inside the struct netif
+   * ifSpeed: no assumption can be made!
+   */
+  NETIF_INIT_SNMP(netif, snmp_ifType_softwareLoopback, 0);
+
+  netif->name[0] = 'l';
+  netif->name[1] = 'o';
+  netif->output = netif_loop_output;
+  return ERR_OK;
+}
+#endif /* LWIP_HAVE_LOOPIF */
+
+void
+netif_init(void)
+{
+#if LWIP_HAVE_LOOPIF
+  ip_addr_t loop_ipaddr, loop_netmask, loop_gw;
+  IP4_ADDR(&loop_gw, 127,0,0,1);
+  IP4_ADDR(&loop_ipaddr, 127,0,0,1);
+  IP4_ADDR(&loop_netmask, 255,0,0,0);
+
+#if NO_SYS
+  netif_add(&loop_netif, &loop_ipaddr, &loop_netmask, &loop_gw, NULL, netif_loopif_init, ip_input);
+#else  /* NO_SYS */
+  netif_add(&loop_netif, &loop_ipaddr, &loop_netmask, &loop_gw, NULL, netif_loopif_init, tcpip_input);
+#endif /* NO_SYS */
+  netif_set_up(&loop_netif);
+
+#endif /* LWIP_HAVE_LOOPIF */
+}
+
+/**
+ * Add a network interface to the list of lwIP netifs.
+ *
+ * @param netif a pre-allocated netif structure
+ * @param ipaddr IP address for the new netif
+ * @param netmask network mask for the new netif
+ * @param gw default gateway IP address for the new netif
+ * @param state opaque data passed to the new netif
+ * @param init callback function that initializes the interface
+ * @param input callback function that is called to pass
+ * ingress packets up in the protocol layer stack.
+ *
+ * @return netif, or NULL if failed.
+ */
+struct netif *
+netif_add(struct netif *netif, ip_addr_t *ipaddr, ip_addr_t *netmask,
+  ip_addr_t *gw, void *state, netif_init_fn init, netif_input_fn input)
+{
+
+  LWIP_ASSERT("No init function given", init != NULL);
+
+  /* reset new interface configuration state */
+  ip_addr_set_zero(&netif->ip_addr);
+  ip_addr_set_zero(&netif->netmask);
+  ip_addr_set_zero(&netif->gw);
+  netif->flags = 0;
+#if LWIP_DHCP
+  /* netif not under DHCP control by default */
+  netif->dhcp = NULL;
+#endif /* LWIP_DHCP */
+#if LWIP_AUTOIP
+  /* netif not under AutoIP control by default */
+  netif->autoip = NULL;
+#endif /* LWIP_AUTOIP */
+#if LWIP_NETIF_STATUS_CALLBACK
+  netif->status_callback = NULL;
+#endif /* LWIP_NETIF_STATUS_CALLBACK */
+#if LWIP_NETIF_LINK_CALLBACK
+  netif->link_callback = NULL;
+#endif /* LWIP_NETIF_LINK_CALLBACK */
+#if LWIP_IGMP
+  netif->igmp_mac_filter = NULL;
+#endif /* LWIP_IGMP */
+#if ENABLE_LOOPBACK
+  netif->loop_first = NULL;
+  netif->loop_last = NULL;
+#endif /* ENABLE_LOOPBACK */
+
+  /* remember netif specific state information data */
+  netif->state = state;
+  netif->num = netif_num++;
+  netif->input = input;
+  NETIF_SET_HWADDRHINT(netif, NULL);
+#if ENABLE_LOOPBACK && LWIP_LOOPBACK_MAX_PBUFS
+  netif->loop_cnt_current = 0;
+#endif /* ENABLE_LOOPBACK && LWIP_LOOPBACK_MAX_PBUFS */
+
+  netif_set_addr(netif, ipaddr, netmask, gw);
+
+  /* call user specified initialization function for netif */
+  if (init(netif) != ERR_OK) {
+    return NULL;
+  }
+
+  /* add this netif to the list */
+  netif->next = netif_list;
+  netif_list = netif;
+  snmp_inc_iflist();
+
+#if LWIP_IGMP
+  /* start IGMP processing */
+  if (netif->flags & NETIF_FLAG_IGMP) {
+    igmp_start(netif);
+  }
+#endif /* LWIP_IGMP */
+
+  LWIP_DEBUGF(NETIF_DEBUG, ("netif: added interface %c%c IP addr ",
+    netif->name[0], netif->name[1]));
+  ip_addr_debug_print(NETIF_DEBUG, ipaddr);
+  LWIP_DEBUGF(NETIF_DEBUG, (" netmask "));
+  ip_addr_debug_print(NETIF_DEBUG, netmask);
+  LWIP_DEBUGF(NETIF_DEBUG, (" gw "));
+  ip_addr_debug_print(NETIF_DEBUG, gw);
+  LWIP_DEBUGF(NETIF_DEBUG, ("\n"));
+  return netif;
+}
+
+/**
+ * Change IP address configuration for a network interface (including netmask
+ * and default gateway).
+ *
+ * @param netif the network interface to change
+ * @param ipaddr the new IP address
+ * @param netmask the new netmask
+ * @param gw the new default gateway
+ */
+void
+netif_set_addr(struct netif *netif, ip_addr_t *ipaddr, ip_addr_t *netmask,
+    ip_addr_t *gw)
+{
+  netif_set_ipaddr(netif, ipaddr);
+  netif_set_netmask(netif, netmask);
+  netif_set_gw(netif, gw);
+}
+
+/**
+ * Remove a network interface from the list of lwIP netifs.
+ *
+ * @param netif the network interface to remove
+ */
+void
+netif_remove(struct netif *netif)
+{
+  if (netif == NULL) {
+    return;
+  }
+
+#if LWIP_IGMP
+  /* stop IGMP processing */
+  if (netif->flags & NETIF_FLAG_IGMP) {
+    igmp_stop(netif);
+  }
+#endif /* LWIP_IGMP */
+  if (netif_is_up(netif)) {
+    /* set netif down before removing (call callback function) */
+    netif_set_down(netif);
+  }
+
+  snmp_delete_ipaddridx_tree(netif);
+
+  /*  is it the first netif? */
+  if (netif_list == netif) {
+    netif_list = netif->next;
+  } else {
+    /*  look for netif further down the list */
+    struct netif * tmpNetif;
+    for (tmpNetif = netif_list; tmpNetif != NULL; tmpNetif = tmpNetif->next) {
+      if (tmpNetif->next == netif) {
+        tmpNetif->next = netif->next;
+        break;
+      }
+    }
+    if (tmpNetif == NULL)
+      return; /*  we didn't find any netif today */
+  }
+  snmp_dec_iflist();
+  /* this netif is default? */
+  if (netif_default == netif) {
+    /* reset default netif */
+    netif_set_default(NULL);
+  }
+#if LWIP_NETIF_REMOVE_CALLBACK
+  if (netif->remove_callback) {
+    netif->remove_callback(netif);
+  }
+#endif /* LWIP_NETIF_REMOVE_CALLBACK */
+  LWIP_DEBUGF( NETIF_DEBUG, ("netif_remove: removed netif\n") );
+}
+
+/**
+ * Find a network interface by searching for its name
+ *
+ * @param name the name of the netif (like netif->name) plus concatenated number
+ * in ascii representation (e.g. 'en0')
+ */
+struct netif *
+netif_find(char *name)
+{
+  struct netif *netif;
+  u8_t num;
+
+  if (name == NULL) {
+    return NULL;
+  }
+
+  num = name[2] - '0';
+
+  for(netif = netif_list; netif != NULL; netif = netif->next) {
+    if (num == netif->num &&
+       name[0] == netif->name[0] &&
+       name[1] == netif->name[1]) {
+      LWIP_DEBUGF(NETIF_DEBUG, ("netif_find: found %c%c\n", name[0], name[1]));
+      return netif;
+    }
+  }
+  LWIP_DEBUGF(NETIF_DEBUG, ("netif_find: didn't find %c%c\n", name[0], name[1]));
+  return NULL;
+}
+
+/**
+ * Change the IP address of a network interface
+ *
+ * @param netif the network interface to change
+ * @param ipaddr the new IP address
+ *
+ * @note call netif_set_addr() if you also want to change netmask and
+ * default gateway
+ */
+void
+netif_set_ipaddr(struct netif *netif, ip_addr_t *ipaddr)
+{
+  /* TODO: Handling of obsolete pcbs */
+  /* See:  http://mail.gnu.org/archive/html/lwip-users/2003-03/msg00118.html */
+#if LWIP_TCP
+  struct tcp_pcb *pcb;
+  struct tcp_pcb_listen *lpcb;
+
+  /* address is actually being changed? */
+  if (ipaddr && (ip_addr_cmp(ipaddr, &(netif->ip_addr))) == 0) {
+    /* extern struct tcp_pcb *tcp_active_pcbs; defined by tcp.h */
+    LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_STATE, ("netif_set_ipaddr: netif address being changed\n"));
+    pcb = tcp_active_pcbs;
+    while (pcb != NULL) {
+      /* PCB bound to current local interface address? */
+      if (ip_addr_cmp(&(pcb->local_ip), &(netif->ip_addr))
+#if LWIP_AUTOIP
+        /* connections to link-local addresses must persist (RFC3927 ch. 1.9) */
+        && !ip_addr_islinklocal(&(pcb->local_ip))
+#endif /* LWIP_AUTOIP */
+        ) {
+        /* this connection must be aborted */
+        struct tcp_pcb *next = pcb->next;
+        LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_STATE, ("netif_set_ipaddr: aborting TCP pcb %p\n", (void *)pcb));
+        tcp_abort(pcb);
+        pcb = next;
+      } else {
+        pcb = pcb->next;
+      }
+    }
+    for (lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
+      /* PCB bound to current local interface address? */
+      if ((!(ip_addr_isany(&(lpcb->local_ip)))) &&
+          (ip_addr_cmp(&(lpcb->local_ip), &(netif->ip_addr)))) {
+        /* The PCB is listening to the old ipaddr and
+         * is set to listen to the new one instead */
+        ip_addr_set(&(lpcb->local_ip), ipaddr);
+      }
+    }
+  }
+#endif
+  snmp_delete_ipaddridx_tree(netif);
+  snmp_delete_iprteidx_tree(0,netif);
+  /* set new IP address to netif */
+  ip_addr_set(&(netif->ip_addr), ipaddr);
+  snmp_insert_ipaddridx_tree(netif);
+  snmp_insert_iprteidx_tree(0,netif);
+
+  LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("netif: IP address of interface %c%c set to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+    netif->name[0], netif->name[1],
+    ip4_addr1_16(&netif->ip_addr),
+    ip4_addr2_16(&netif->ip_addr),
+    ip4_addr3_16(&netif->ip_addr),
+    ip4_addr4_16(&netif->ip_addr)));
+}
+
+/**
+ * Change the default gateway for a network interface
+ *
+ * @param netif the network interface to change
+ * @param gw the new default gateway
+ *
+ * @note call netif_set_addr() if you also want to change ip address and netmask
+ */
+void
+netif_set_gw(struct netif *netif, ip_addr_t *gw)
+{
+  ip_addr_set(&(netif->gw), gw);
+  LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("netif: GW address of interface %c%c set to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+    netif->name[0], netif->name[1],
+    ip4_addr1_16(&netif->gw),
+    ip4_addr2_16(&netif->gw),
+    ip4_addr3_16(&netif->gw),
+    ip4_addr4_16(&netif->gw)));
+}
+
+/**
+ * Change the netmask of a network interface
+ *
+ * @param netif the network interface to change
+ * @param netmask the new netmask
+ *
+ * @note call netif_set_addr() if you also want to change ip address and
+ * default gateway
+ */
+void
+netif_set_netmask(struct netif *netif, ip_addr_t *netmask)
+{
+  snmp_delete_iprteidx_tree(0, netif);
+  /* set new netmask to netif */
+  ip_addr_set(&(netif->netmask), netmask);
+  snmp_insert_iprteidx_tree(0, netif);
+  LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("netif: netmask of interface %c%c set to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+    netif->name[0], netif->name[1],
+    ip4_addr1_16(&netif->netmask),
+    ip4_addr2_16(&netif->netmask),
+    ip4_addr3_16(&netif->netmask),
+    ip4_addr4_16(&netif->netmask)));
+}
+
+/**
+ * Set a network interface as the default network interface
+ * (used to output all packets for which no specific route is found)
+ *
+ * @param netif the default network interface
+ */
+void
+netif_set_default(struct netif *netif)
+{
+  if (netif == NULL) {
+    /* remove default route */
+    snmp_delete_iprteidx_tree(1, netif);
+  } else {
+    /* install default route */
+    snmp_insert_iprteidx_tree(1, netif);
+  }
+  netif_default = netif;
+  LWIP_DEBUGF(NETIF_DEBUG, ("netif: setting default interface %c%c\n",
+           netif ? netif->name[0] : '\'', netif ? netif->name[1] : '\''));
+}
+
+/**
+ * Bring an interface up, available for processing
+ * traffic.
+ * 
+ * @note: Enabling DHCP on a down interface will make it come
+ * up once configured.
+ * 
+ * @see dhcp_start()
+ */ 
+void netif_set_up(struct netif *netif)
+{
+  if (!(netif->flags & NETIF_FLAG_UP)) {
+    netif->flags |= NETIF_FLAG_UP;
+    
+#if LWIP_SNMP
+    snmp_get_sysuptime(&netif->ts);
+#endif /* LWIP_SNMP */
+
+    NETIF_STATUS_CALLBACK(netif);
+
+    if (netif->flags & NETIF_FLAG_LINK_UP) {
+#if LWIP_ARP
+      /* For Ethernet network interfaces, we would like to send a "gratuitous ARP" */ 
+      if (netif->flags & (NETIF_FLAG_ETHARP)) {
+        etharp_gratuitous(netif);
+      }
+#endif /* LWIP_ARP */
+
+#if LWIP_IGMP
+      /* resend IGMP memberships */
+      if (netif->flags & NETIF_FLAG_IGMP) {
+        igmp_report_groups( netif);
+      }
+#endif /* LWIP_IGMP */
+    }
+  }
+}
+
+/**
+ * Bring an interface down, disabling any traffic processing.
+ *
+ * @note: Enabling DHCP on a down interface will make it come
+ * up once configured.
+ * 
+ * @see dhcp_start()
+ */ 
+void netif_set_down(struct netif *netif)
+{
+  if (netif->flags & NETIF_FLAG_UP) {
+    netif->flags &= ~NETIF_FLAG_UP;
+#if LWIP_SNMP
+    snmp_get_sysuptime(&netif->ts);
+#endif
+
+#if LWIP_ARP
+    if (netif->flags & NETIF_FLAG_ETHARP) {
+      etharp_cleanup_netif(netif);
+    }
+#endif /* LWIP_ARP */
+    NETIF_STATUS_CALLBACK(netif);
+  }
+}
+
+#if LWIP_NETIF_STATUS_CALLBACK
+/**
+ * Set callback to be called when interface is brought up/down
+ */
+void netif_set_status_callback(struct netif *netif, netif_status_callback_fn status_callback)
+{
+  if (netif) {
+    netif->status_callback = status_callback;
+  }
+}
+#endif /* LWIP_NETIF_STATUS_CALLBACK */
+
+#if LWIP_NETIF_REMOVE_CALLBACK
+/**
+ * Set callback to be called when the interface has been removed
+ */
+void
+netif_set_remove_callback(struct netif *netif, netif_status_callback_fn remove_callback)
+{
+  if (netif) {
+    netif->remove_callback = remove_callback;
+  }
+}
+#endif /* LWIP_NETIF_REMOVE_CALLBACK */
+
+/**
+ * Called by a driver when its link goes up
+ */
+void netif_set_link_up(struct netif *netif )
+{
+  if (!(netif->flags & NETIF_FLAG_LINK_UP)) {
+    netif->flags |= NETIF_FLAG_LINK_UP;
+
+#if LWIP_DHCP
+    if (netif->dhcp) {
+      dhcp_network_changed(netif);
+    }
+#endif /* LWIP_DHCP */
+
+#if LWIP_AUTOIP
+    if (netif->autoip) {
+      autoip_network_changed(netif);
+    }
+#endif /* LWIP_AUTOIP */
+
+    if (netif->flags & NETIF_FLAG_UP) {
+#if LWIP_ARP
+      /* For Ethernet network interfaces, we would like to send a "gratuitous ARP" */ 
+      if (netif->flags & NETIF_FLAG_ETHARP) {
+        etharp_gratuitous(netif);
+      }
+#endif /* LWIP_ARP */
+
+#if LWIP_IGMP
+      /* resend IGMP memberships */
+      if (netif->flags & NETIF_FLAG_IGMP) {
+        igmp_report_groups( netif);
+      }
+#endif /* LWIP_IGMP */
+    }
+    NETIF_LINK_CALLBACK(netif);
+  }
+}
+
+/**
+ * Called by a driver when its link goes down
+ */
+void netif_set_link_down(struct netif *netif )
+{
+  if (netif->flags & NETIF_FLAG_LINK_UP) {
+    netif->flags &= ~NETIF_FLAG_LINK_UP;
+    NETIF_LINK_CALLBACK(netif);
+  }
+}
+
+#if LWIP_NETIF_LINK_CALLBACK
+/**
+ * Set callback to be called when link is brought up/down
+ */
+void netif_set_link_callback(struct netif *netif, netif_status_callback_fn link_callback)
+{
+  if (netif) {
+    netif->link_callback = link_callback;
+  }
+}
+#endif /* LWIP_NETIF_LINK_CALLBACK */
+
+#if ENABLE_LOOPBACK
+/**
+ * Send an IP packet to be received on the same netif (loopif-like).
+ * The pbuf is simply copied and handed back to netif->input.
+ * In multithreaded mode, this is done directly since netif->input must put
+ * the packet on a queue.
+ * In callback mode, the packet is put on an internal queue and is fed to
+ * netif->input by netif_poll().
+ *
+ * @param netif the lwip network interface structure
+ * @param p the (IP) packet to 'send'
+ * @param ipaddr the ip address to send the packet to (not used)
+ * @return ERR_OK if the packet has been sent
+ *         ERR_MEM if the pbuf used to copy the packet couldn't be allocated
+ */
+err_t
+netif_loop_output(struct netif *netif, struct pbuf *p,
+       ip_addr_t *ipaddr)
+{
+  struct pbuf *r;
+  err_t err;
+  struct pbuf *last;
+#if LWIP_LOOPBACK_MAX_PBUFS
+  u8_t clen = 0;
+#endif /* LWIP_LOOPBACK_MAX_PBUFS */
+  /* If we have a loopif, SNMP counters are adjusted for it,
+   * if not they are adjusted for 'netif'. */
+#if LWIP_SNMP
+#if LWIP_HAVE_LOOPIF
+  struct netif *stats_if = &loop_netif;
+#else /* LWIP_HAVE_LOOPIF */
+  struct netif *stats_if = netif;
+#endif /* LWIP_HAVE_LOOPIF */
+#endif /* LWIP_SNMP */
+  SYS_ARCH_DECL_PROTECT(lev);
+  LWIP_UNUSED_ARG(ipaddr);
+
+  /* Allocate a new pbuf */
+  r = pbuf_alloc(PBUF_LINK, p->tot_len, PBUF_RAM);
+  if (r == NULL) {
+    LINK_STATS_INC(link.memerr);
+    LINK_STATS_INC(link.drop);
+    snmp_inc_ifoutdiscards(stats_if);
+    return ERR_MEM;
+  }
+#if LWIP_LOOPBACK_MAX_PBUFS
+  clen = pbuf_clen(r);
+  /* check for overflow or too many pbuf on queue */
+  if(((netif->loop_cnt_current + clen) < netif->loop_cnt_current) ||
+     ((netif->loop_cnt_current + clen) > LWIP_LOOPBACK_MAX_PBUFS)) {
+    pbuf_free(r);
+    LINK_STATS_INC(link.memerr);
+    LINK_STATS_INC(link.drop);
+    snmp_inc_ifoutdiscards(stats_if);
+    return ERR_MEM;
+  }
+  netif->loop_cnt_current += clen;
+#endif /* LWIP_LOOPBACK_MAX_PBUFS */
+
+  /* Copy the whole pbuf queue p into the single pbuf r */
+  if ((err = pbuf_copy(r, p)) != ERR_OK) {
+    pbuf_free(r);
+    LINK_STATS_INC(link.memerr);
+    LINK_STATS_INC(link.drop);
+    snmp_inc_ifoutdiscards(stats_if);
+    return err;
+  }
+
+  /* Put the packet on a linked list which gets emptied through calling
+     netif_poll(). */
+
+  /* let last point to the last pbuf in chain r */
+  for (last = r; last->next != NULL; last = last->next);
+
+  SYS_ARCH_PROTECT(lev);
+  if(netif->loop_first != NULL) {
+    LWIP_ASSERT("if first != NULL, last must also be != NULL", netif->loop_last != NULL);
+    netif->loop_last->next = r;
+    netif->loop_last = last;
+  } else {
+    netif->loop_first = r;
+    netif->loop_last = last;
+  }
+  SYS_ARCH_UNPROTECT(lev);
+
+  LINK_STATS_INC(link.xmit);
+  snmp_add_ifoutoctets(stats_if, p->tot_len);
+  snmp_inc_ifoutucastpkts(stats_if);
+
+#if LWIP_NETIF_LOOPBACK_MULTITHREADING
+  /* For multithreading environment, schedule a call to netif_poll */
+  tcpip_callback((tcpip_callback_fn)netif_poll, netif);
+#endif /* LWIP_NETIF_LOOPBACK_MULTITHREADING */
+
+  return ERR_OK;
+}
+
+/**
+ * Call netif_poll() in the main loop of your application. This is to prevent
+ * reentering non-reentrant functions like tcp_input(). Packets passed to
+ * netif_loop_output() are put on a list that is passed to netif->input() by
+ * netif_poll().
+ */
+void
+netif_poll(struct netif *netif)
+{
+  struct pbuf *in;
+  /* If we have a loopif, SNMP counters are adjusted for it,
+   * if not they are adjusted for 'netif'. */
+#if LWIP_SNMP
+#if LWIP_HAVE_LOOPIF
+  struct netif *stats_if = &loop_netif;
+#else /* LWIP_HAVE_LOOPIF */
+  struct netif *stats_if = netif;
+#endif /* LWIP_HAVE_LOOPIF */
+#endif /* LWIP_SNMP */
+  SYS_ARCH_DECL_PROTECT(lev);
+
+  do {
+    /* Get a packet from the list. With SYS_LIGHTWEIGHT_PROT=1, this is protected */
+    SYS_ARCH_PROTECT(lev);
+    in = netif->loop_first;
+    if (in != NULL) {
+      struct pbuf *in_end = in;
+#if LWIP_LOOPBACK_MAX_PBUFS
+      u8_t clen = pbuf_clen(in);
+      /* adjust the number of pbufs on queue */
+      LWIP_ASSERT("netif->loop_cnt_current underflow",
+        ((netif->loop_cnt_current - clen) < netif->loop_cnt_current));
+      netif->loop_cnt_current -= clen;
+#endif /* LWIP_LOOPBACK_MAX_PBUFS */
+      while (in_end->len != in_end->tot_len) {
+        LWIP_ASSERT("bogus pbuf: len != tot_len but next == NULL!", in_end->next != NULL);
+        in_end = in_end->next;
+      }
+      /* 'in_end' now points to the last pbuf from 'in' */
+      if (in_end == netif->loop_last) {
+        /* this was the last pbuf in the list */
+        netif->loop_first = netif->loop_last = NULL;
+      } else {
+        /* pop the pbuf off the list */
+        netif->loop_first = in_end->next;
+        LWIP_ASSERT("should not be null since first != last!", netif->loop_first != NULL);
+      }
+      /* De-queue the pbuf from its successors on the 'loop_' list. */
+      in_end->next = NULL;
+    }
+    SYS_ARCH_UNPROTECT(lev);
+
+    if (in != NULL) {
+      LINK_STATS_INC(link.recv);
+      snmp_add_ifinoctets(stats_if, in->tot_len);
+      snmp_inc_ifinucastpkts(stats_if);
+      /* loopback packets are always IP packets! */
+      if (ip_input(in, netif) != ERR_OK) {
+        pbuf_free(in);
+      }
+      /* Don't reference the packet any more! */
+      in = NULL;
+    }
+  /* go on while there is a packet on the list */
+  } while (netif->loop_first != NULL);
+}
+
+#if !LWIP_NETIF_LOOPBACK_MULTITHREADING
+/**
+ * Calls netif_poll() for every netif on the netif_list.
+ */
+void
+netif_poll_all(void)
+{
+  struct netif *netif = netif_list;
+  /* loop through netifs */
+  while (netif != NULL) {
+    netif_poll(netif);
+    /* proceed to next network interface */
+    netif = netif->next;
+  }
+}
+#endif /* !LWIP_NETIF_LOOPBACK_MULTITHREADING */
+#endif /* ENABLE_LOOPBACK */

src/lwip-1.4.1/src/core/raw.c

@@ -0,0 +1,350 @@
+/**
+ * @file
+ * Implementation of raw protocol PCBs for low-level handling of
+ * different types of protocols besides (or overriding) those
+ * already available in lwIP.
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_RAW /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/def.h"
+#include "lwip/memp.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+#include "lwip/raw.h"
+#include "lwip/stats.h"
+#include "arch/perf.h"
+
+#include <string.h>
+
+/** The list of RAW PCBs */
+static struct raw_pcb *raw_pcbs;
+
+/**
+ * Determine if in incoming IP packet is covered by a RAW PCB
+ * and if so, pass it to a user-provided receive callback function.
+ *
+ * Given an incoming IP datagram (as a chain of pbufs) this function
+ * finds a corresponding RAW PCB and calls the corresponding receive
+ * callback function.
+ *
+ * @param p pbuf to be demultiplexed to a RAW PCB.
+ * @param inp network interface on which the datagram was received.
+ * @return - 1 if the packet has been eaten by a RAW PCB receive
+ *           callback function. The caller MAY NOT not reference the
+ *           packet any longer, and MAY NOT call pbuf_free().
+ * @return - 0 if packet is not eaten (pbuf is still referenced by the
+ *           caller).
+ *
+ */
+u8_t
+raw_input(struct pbuf *p, struct netif *inp)
+{
+  struct raw_pcb *pcb, *prev;
+  struct ip_hdr *iphdr;
+  s16_t proto;
+  u8_t eaten = 0;
+
+  LWIP_UNUSED_ARG(inp);
+
+  iphdr = (struct ip_hdr *)p->payload;
+  proto = IPH_PROTO(iphdr);
+
+  prev = NULL;
+  pcb = raw_pcbs;
+  /* loop through all raw pcbs until the packet is eaten by one */
+  /* this allows multiple pcbs to match against the packet by design */
+  while ((eaten == 0) && (pcb != NULL)) {
+    if ((pcb->protocol == proto) &&
+        (ip_addr_isany(&pcb->local_ip) ||
+         ip_addr_cmp(&(pcb->local_ip), &current_iphdr_dest))) {
+#if IP_SOF_BROADCAST_RECV
+      /* broadcast filter? */
+      if (ip_get_option(pcb, SOF_BROADCAST) || !ip_addr_isbroadcast(&current_iphdr_dest, inp))
+#endif /* IP_SOF_BROADCAST_RECV */
+      {
+        /* receive callback function available? */
+        if (pcb->recv != NULL) {
+          /* the receive callback function did not eat the packet? */
+          if (pcb->recv(pcb->recv_arg, pcb, p, ip_current_src_addr()) != 0) {
+            /* receive function ate the packet */
+            p = NULL;
+            eaten = 1;
+            if (prev != NULL) {
+            /* move the pcb to the front of raw_pcbs so that is
+               found faster next time */
+              prev->next = pcb->next;
+              pcb->next = raw_pcbs;
+              raw_pcbs = pcb;
+            }
+          }
+        }
+        /* no receive callback function was set for this raw PCB */
+      }
+      /* drop the packet */
+    }
+    prev = pcb;
+    pcb = pcb->next;
+  }
+  return eaten;
+}
+
+/**
+ * Bind a RAW PCB.
+ *
+ * @param pcb RAW PCB to be bound with a local address ipaddr.
+ * @param ipaddr local IP address to bind with. Use IP_ADDR_ANY to
+ * bind to all local interfaces.
+ *
+ * @return lwIP error code.
+ * - ERR_OK. Successful. No error occured.
+ * - ERR_USE. The specified IP address is already bound to by
+ * another RAW PCB.
+ *
+ * @see raw_disconnect()
+ */
+err_t
+raw_bind(struct raw_pcb *pcb, ip_addr_t *ipaddr)
+{
+  ip_addr_set(&pcb->local_ip, ipaddr);
+  return ERR_OK;
+}
+
+/**
+ * Connect an RAW PCB. This function is required by upper layers
+ * of lwip. Using the raw api you could use raw_sendto() instead
+ *
+ * This will associate the RAW PCB with the remote address.
+ *
+ * @param pcb RAW PCB to be connected with remote address ipaddr and port.
+ * @param ipaddr remote IP address to connect with.
+ *
+ * @return lwIP error code
+ *
+ * @see raw_disconnect() and raw_sendto()
+ */
+err_t
+raw_connect(struct raw_pcb *pcb, ip_addr_t *ipaddr)
+{
+  ip_addr_set(&pcb->remote_ip, ipaddr);
+  return ERR_OK;
+}
+
+
+/**
+ * Set the callback function for received packets that match the
+ * raw PCB's protocol and binding. 
+ * 
+ * The callback function MUST either
+ * - eat the packet by calling pbuf_free() and returning non-zero. The
+ *   packet will not be passed to other raw PCBs or other protocol layers.
+ * - not free the packet, and return zero. The packet will be matched
+ *   against further PCBs and/or forwarded to another protocol layers.
+ * 
+ * @return non-zero if the packet was free()d, zero if the packet remains
+ * available for others.
+ */
+void
+raw_recv(struct raw_pcb *pcb, raw_recv_fn recv, void *recv_arg)
+{
+  /* remember recv() callback and user data */
+  pcb->recv = recv;
+  pcb->recv_arg = recv_arg;
+}
+
+/**
+ * Send the raw IP packet to the given address. Note that actually you cannot
+ * modify the IP headers (this is inconsistent with the receive callback where
+ * you actually get the IP headers), you can only specify the IP payload here.
+ * It requires some more changes in lwIP. (there will be a raw_send() function
+ * then.)
+ *
+ * @param pcb the raw pcb which to send
+ * @param p the IP payload to send
+ * @param ipaddr the destination address of the IP packet
+ *
+ */
+err_t
+raw_sendto(struct raw_pcb *pcb, struct pbuf *p, ip_addr_t *ipaddr)
+{
+  err_t err;
+  struct netif *netif;
+  ip_addr_t *src_ip;
+  struct pbuf *q; /* q will be sent down the stack */
+  
+  LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_TRACE, ("raw_sendto\n"));
+  
+  /* not enough space to add an IP header to first pbuf in given p chain? */
+  if (pbuf_header(p, IP_HLEN)) {
+    /* allocate header in new pbuf */
+    q = pbuf_alloc(PBUF_IP, 0, PBUF_RAM);
+    /* new header pbuf could not be allocated? */
+    if (q == NULL) {
+      LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("raw_sendto: could not allocate header\n"));
+      return ERR_MEM;
+    }
+    if (p->tot_len != 0) {
+      /* chain header q in front of given pbuf p */
+      pbuf_chain(q, p);
+    }
+    /* { first pbuf q points to header pbuf } */
+    LWIP_DEBUGF(RAW_DEBUG, ("raw_sendto: added header pbuf %p before given pbuf %p\n", (void *)q, (void *)p));
+  }  else {
+    /* first pbuf q equals given pbuf */
+    q = p;
+    if(pbuf_header(q, -IP_HLEN)) {
+      LWIP_ASSERT("Can't restore header we just removed!", 0);
+      return ERR_MEM;
+    }
+  }
+
+  if ((netif = ip_route(ipaddr)) == NULL) {
+    LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_LEVEL_WARNING, ("raw_sendto: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+      ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr)));
+    /* free any temporary header pbuf allocated by pbuf_header() */
+    if (q != p) {
+      pbuf_free(q);
+    }
+    return ERR_RTE;
+  }
+
+#if IP_SOF_BROADCAST
+  /* broadcast filter? */
+  if (!ip_get_option(pcb, SOF_BROADCAST) && ip_addr_isbroadcast(ipaddr, netif)) {
+    LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_LEVEL_WARNING, ("raw_sendto: SOF_BROADCAST not enabled on pcb %p\n", (void *)pcb));
+    /* free any temporary header pbuf allocated by pbuf_header() */
+    if (q != p) {
+      pbuf_free(q);
+    }
+    return ERR_VAL;
+  }
+#endif /* IP_SOF_BROADCAST */
+
+  if (ip_addr_isany(&pcb->local_ip)) {
+    /* use outgoing network interface IP address as source address */
+    src_ip = &(netif->ip_addr);
+  } else {
+    /* use RAW PCB local IP address as source address */
+    src_ip = &(pcb->local_ip);
+  }
+
+  NETIF_SET_HWADDRHINT(netif, &pcb->addr_hint);
+  err = ip_output_if (q, src_ip, ipaddr, pcb->ttl, pcb->tos, pcb->protocol, netif);
+  NETIF_SET_HWADDRHINT(netif, NULL);
+
+  /* did we chain a header earlier? */
+  if (q != p) {
+    /* free the header */
+    pbuf_free(q);
+  }
+  return err;
+}
+
+/**
+ * Send the raw IP packet to the address given by raw_connect()
+ *
+ * @param pcb the raw pcb which to send
+ * @param p the IP payload to send
+ *
+ */
+err_t
+raw_send(struct raw_pcb *pcb, struct pbuf *p)
+{
+  return raw_sendto(pcb, p, &pcb->remote_ip);
+}
+
+/**
+ * Remove an RAW PCB.
+ *
+ * @param pcb RAW PCB to be removed. The PCB is removed from the list of
+ * RAW PCB's and the data structure is freed from memory.
+ *
+ * @see raw_new()
+ */
+void
+raw_remove(struct raw_pcb *pcb)
+{
+  struct raw_pcb *pcb2;
+  /* pcb to be removed is first in list? */
+  if (raw_pcbs == pcb) {
+    /* make list start at 2nd pcb */
+    raw_pcbs = raw_pcbs->next;
+    /* pcb not 1st in list */
+  } else {
+    for(pcb2 = raw_pcbs; pcb2 != NULL; pcb2 = pcb2->next) {
+      /* find pcb in raw_pcbs list */
+      if (pcb2->next != NULL && pcb2->next == pcb) {
+        /* remove pcb from list */
+        pcb2->next = pcb->next;
+      }
+    }
+  }
+  memp_free(MEMP_RAW_PCB, pcb);
+}
+
+/**
+ * Create a RAW PCB.
+ *
+ * @return The RAW PCB which was created. NULL if the PCB data structure
+ * could not be allocated.
+ *
+ * @param proto the protocol number of the IPs payload (e.g. IP_PROTO_ICMP)
+ *
+ * @see raw_remove()
+ */
+struct raw_pcb *
+raw_new(u8_t proto)
+{
+  struct raw_pcb *pcb;
+
+  LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_TRACE, ("raw_new\n"));
+
+  pcb = (struct raw_pcb *)memp_malloc(MEMP_RAW_PCB);
+  /* could allocate RAW PCB? */
+  if (pcb != NULL) {
+    /* initialize PCB to all zeroes */
+    memset(pcb, 0, sizeof(struct raw_pcb));
+    pcb->protocol = proto;
+    pcb->ttl = RAW_TTL;
+    pcb->next = raw_pcbs;
+    raw_pcbs = pcb;
+  }
+  return pcb;
+}
+
+#endif /* LWIP_RAW */

src/lwip-1.4.1/src/core/snmp/asn1_dec.c

@@ -0,0 +1,657 @@
+/**
+ * @file
+ * Abstract Syntax Notation One (ISO 8824, 8825) decoding
+ *
+ * @todo not optimised (yet), favor correctness over speed, favor speed over size
+ */
+
+/*
+ * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * Author: Christiaan Simons <christiaan.simons@axon.tv>
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/snmp_asn1.h"
+
+/**
+ * Retrieves type field from incoming pbuf chain.
+ *
+ * @param p points to a pbuf holding an ASN1 coded type field
+ * @param ofs points to the offset within the pbuf chain of the ASN1 coded type field
+ * @param type return ASN1 type
+ * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode
+ */
+err_t
+snmp_asn1_dec_type(struct pbuf *p, u16_t ofs, u8_t *type)
+{
+  u16_t plen, base;
+  u8_t *msg_ptr;
+
+  plen = 0;
+  while (p != NULL)
+  {
+    base = plen;
+    plen += p->len;
+    if (ofs < plen)
+    {
+      msg_ptr = (u8_t*)p->payload;
+      msg_ptr += ofs - base;
+      *type = *msg_ptr;
+      return ERR_OK;
+    }
+    p = p->next;
+  }
+  /* p == NULL, ofs >= plen */
+  return ERR_ARG;
+}
+
+/**
+ * Decodes length field from incoming pbuf chain into host length.
+ *
+ * @param p points to a pbuf holding an ASN1 coded length
+ * @param ofs points to the offset within the pbuf chain of the ASN1 coded length
+ * @param octets_used returns number of octets used by the length code
+ * @param length return host order length, upto 64k
+ * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode
+ */
+err_t
+snmp_asn1_dec_length(struct pbuf *p, u16_t ofs, u8_t *octets_used, u16_t *length)
+{
+  u16_t plen, base;
+  u8_t *msg_ptr;
+
+  plen = 0;
+  while (p != NULL)
+  {
+    base = plen;
+    plen += p->len;
+    if (ofs < plen)
+    {
+      msg_ptr = (u8_t*)p->payload;
+      msg_ptr += ofs - base;
+
+      if (*msg_ptr < 0x80)
+      {
+        /* primitive definite length format */
+        *octets_used = 1;
+        *length = *msg_ptr;
+        return ERR_OK;
+      }
+      else if (*msg_ptr == 0x80)
+      {
+        /* constructed indefinite length format, termination with two zero octets */
+        u8_t zeros;
+        u8_t i;
+
+        *length = 0;
+        zeros = 0;
+        while (zeros != 2)
+        {
+          i = 2;
+          while (i > 0)
+          {
+            i--;
+            (*length) += 1;
+            ofs += 1;
+            if (ofs >= plen)
+            {
+              /* next octet in next pbuf */
+              p = p->next;
+              if (p == NULL) { return ERR_ARG; }
+              msg_ptr = (u8_t*)p->payload;
+              plen += p->len;
+            }
+            else
+            {
+              /* next octet in same pbuf */
+              msg_ptr++;
+            }
+            if (*msg_ptr == 0)
+            {
+              zeros++;
+              if (zeros == 2)
+              {
+                /* stop while (i > 0) */
+                i = 0;
+              }
+            }
+            else
+            {
+              zeros = 0;
+            }
+          }
+        }
+        *octets_used = 1;
+        return ERR_OK;
+      }
+      else if (*msg_ptr == 0x81)
+      {
+        /* constructed definite length format, one octet */
+        ofs += 1;
+        if (ofs >= plen)
+        {
+          /* next octet in next pbuf */
+          p = p->next;
+          if (p == NULL) { return ERR_ARG; }
+          msg_ptr = (u8_t*)p->payload;
+        }
+        else
+        {
+          /* next octet in same pbuf */
+          msg_ptr++;
+        }
+        *length = *msg_ptr;
+        *octets_used = 2;
+        return ERR_OK;
+      }
+      else if (*msg_ptr == 0x82)
+      {
+        u8_t i;
+
+        /* constructed definite length format, two octets */
+        i = 2;
+        while (i > 0)
+        {
+          i--;
+          ofs += 1;
+          if (ofs >= plen)
+          {
+            /* next octet in next pbuf */
+            p = p->next;
+            if (p == NULL) { return ERR_ARG; }
+            msg_ptr = (u8_t*)p->payload;
+            plen += p->len;
+          }
+          else
+          {
+            /* next octet in same pbuf */
+            msg_ptr++;
+          }
+          if (i == 0)
+          {
+            /* least significant length octet */
+            *length |= *msg_ptr;
+          }
+          else
+          {
+            /* most significant length octet */
+            *length = (*msg_ptr) << 8;
+          }
+        }
+        *octets_used = 3;
+        return ERR_OK;
+      }
+      else
+      {
+        /* constructed definite length format 3..127 octets, this is too big (>64k) */
+        /**  @todo: do we need to accept inefficient codings with many leading zero's? */
+        *octets_used = 1 + ((*msg_ptr) & 0x7f);
+        return ERR_ARG;
+      }
+    }
+    p = p->next;
+  }
+
+  /* p == NULL, ofs >= plen */
+  return ERR_ARG;
+}
+
+/**
+ * Decodes positive integer (counter, gauge, timeticks) into u32_t.
+ *
+ * @param p points to a pbuf holding an ASN1 coded integer
+ * @param ofs points to the offset within the pbuf chain of the ASN1 coded integer
+ * @param len length of the coded integer field
+ * @param value return host order integer
+ * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode
+ *
+ * @note ASN coded integers are _always_ signed. E.g. +0xFFFF is coded
+ * as 0x00,0xFF,0xFF. Note the leading sign octet. A positive value
+ * of 0xFFFFFFFF is preceded with 0x00 and the length is 5 octets!!
+ */
+err_t
+snmp_asn1_dec_u32t(struct pbuf *p, u16_t ofs, u16_t len, u32_t *value)
+{
+  u16_t plen, base;
+  u8_t *msg_ptr;
+
+  plen = 0;
+  while (p != NULL)
+  {
+    base = plen;
+    plen += p->len;
+    if (ofs < plen)
+    {
+      msg_ptr = (u8_t*)p->payload;
+      msg_ptr += ofs - base;
+      if ((len > 0) && (len < 6))
+      {
+        /* start from zero */
+        *value = 0;
+        if (*msg_ptr & 0x80)
+        {
+          /* negative, expecting zero sign bit! */
+          return ERR_ARG;
+        }
+        else
+        {
+          /* positive */
+          if ((len > 1) && (*msg_ptr == 0))
+          {
+            /* skip leading "sign byte" octet 0x00 */
+            len--;
+            ofs += 1;
+            if (ofs >= plen)
+            {
+              /* next octet in next pbuf */
+              p = p->next;
+              if (p == NULL) { return ERR_ARG; }
+              msg_ptr = (u8_t*)p->payload;
+              plen += p->len;
+            }
+            else
+            {
+              /* next octet in same pbuf */
+              msg_ptr++;
+            }
+          }
+        }
+        /* OR octets with value */
+        while (len > 1)
+        {
+          len--;
+          *value |= *msg_ptr;
+          *value <<= 8;
+          ofs += 1;
+          if (ofs >= plen)
+          {
+            /* next octet in next pbuf */
+            p = p->next;
+            if (p == NULL) { return ERR_ARG; }
+            msg_ptr = (u8_t*)p->payload;
+            plen += p->len;
+          }
+          else
+          {
+            /* next octet in same pbuf */
+            msg_ptr++;
+          }
+        }
+        *value |= *msg_ptr;
+        return ERR_OK;
+      }
+      else
+      {
+        return ERR_ARG;
+      }
+    }
+    p = p->next;
+  }
+  /* p == NULL, ofs >= plen */
+  return ERR_ARG;
+}
+
+/**
+ * Decodes integer into s32_t.
+ *
+ * @param p points to a pbuf holding an ASN1 coded integer
+ * @param ofs points to the offset within the pbuf chain of the ASN1 coded integer
+ * @param len length of the coded integer field
+ * @param value return host order integer
+ * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode
+ *
+ * @note ASN coded integers are _always_ signed!
+ */
+err_t
+snmp_asn1_dec_s32t(struct pbuf *p, u16_t ofs, u16_t len, s32_t *value)
+{
+  u16_t plen, base;
+  u8_t *msg_ptr;
+#if BYTE_ORDER == LITTLE_ENDIAN
+  u8_t *lsb_ptr = (u8_t*)value;
+#endif
+#if BYTE_ORDER == BIG_ENDIAN
+  u8_t *lsb_ptr = (u8_t*)value + sizeof(s32_t) - 1;
+#endif
+  u8_t sign;
+
+  plen = 0;
+  while (p != NULL)
+  {
+    base = plen;
+    plen += p->len;
+    if (ofs < plen)
+    {
+      msg_ptr = (u8_t*)p->payload;
+      msg_ptr += ofs - base;
+      if ((len > 0) && (len < 5))
+      {
+        if (*msg_ptr & 0x80)
+        {
+          /* negative, start from -1 */
+          *value = -1;
+          sign = 1;
+        }
+        else
+        {
+          /* positive, start from 0 */
+          *value = 0;
+          sign = 0;
+        }
+        /* OR/AND octets with value */
+        while (len > 1)
+        {
+          len--;
+          if (sign)
+          {
+            *lsb_ptr &= *msg_ptr;
+            *value <<= 8;
+            *lsb_ptr |= 255;
+          }
+          else
+          {
+            *lsb_ptr |= *msg_ptr;
+            *value <<= 8;
+          }
+          ofs += 1;
+          if (ofs >= plen)
+          {
+            /* next octet in next pbuf */
+            p = p->next;
+            if (p == NULL) { return ERR_ARG; }
+            msg_ptr = (u8_t*)p->payload;
+            plen += p->len;
+          }
+          else
+          {
+            /* next octet in same pbuf */
+            msg_ptr++;
+          }
+        }
+        if (sign)
+        {
+          *lsb_ptr &= *msg_ptr;
+        }
+        else
+        {
+          *lsb_ptr |= *msg_ptr;
+        }
+        return ERR_OK;
+      }
+      else
+      {
+        return ERR_ARG;
+      }
+    }
+    p = p->next;
+  }
+  /* p == NULL, ofs >= plen */
+  return ERR_ARG;
+}
+
+/**
+ * Decodes object identifier from incoming message into array of s32_t.
+ *
+ * @param p points to a pbuf holding an ASN1 coded object identifier
+ * @param ofs points to the offset within the pbuf chain of the ASN1 coded object identifier
+ * @param len length of the coded object identifier
+ * @param oid return object identifier struct
+ * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode
+ */
+err_t
+snmp_asn1_dec_oid(struct pbuf *p, u16_t ofs, u16_t len, struct snmp_obj_id *oid)
+{
+  u16_t plen, base;
+  u8_t *msg_ptr;
+  s32_t *oid_ptr;
+
+  plen = 0;
+  while (p != NULL)
+  {
+    base = plen;
+    plen += p->len;
+    if (ofs < plen)
+    {
+      msg_ptr = (u8_t*)p->payload;
+      msg_ptr += ofs - base;
+
+      oid->len = 0;
+      oid_ptr = &oid->id[0];
+      if (len > 0)
+      {
+        /* first compressed octet */
+        if (*msg_ptr == 0x2B)
+        {
+          /* (most) common case 1.3 (iso.org) */
+          *oid_ptr = 1;
+          oid_ptr++;
+          *oid_ptr = 3;
+          oid_ptr++;
+        }
+        else if (*msg_ptr < 40)
+        {
+          *oid_ptr = 0;
+          oid_ptr++;
+          *oid_ptr = *msg_ptr;
+          oid_ptr++;
+        }
+        else if (*msg_ptr < 80)
+        {
+          *oid_ptr = 1;
+          oid_ptr++;
+          *oid_ptr = (*msg_ptr) - 40;
+          oid_ptr++;
+        }
+        else
+        {
+          *oid_ptr = 2;
+          oid_ptr++;
+          *oid_ptr = (*msg_ptr) - 80;
+          oid_ptr++;
+        }
+        oid->len = 2;
+      }
+      else
+      {
+        /* accepting zero length identifiers e.g. for
+           getnext operation. uncommon but valid */
+        return ERR_OK;
+      }
+      len--;
+      if (len > 0)
+      {
+        ofs += 1;
+        if (ofs >= plen)
+        {
+          /* next octet in next pbuf */
+          p = p->next;
+          if (p == NULL) { return ERR_ARG; }
+          msg_ptr = (u8_t*)p->payload;
+          plen += p->len;
+        }
+        else
+        {
+          /* next octet in same pbuf */
+          msg_ptr++;
+        }
+      }
+      while ((len > 0) && (oid->len < LWIP_SNMP_OBJ_ID_LEN))
+      {
+        /* sub-identifier uses multiple octets */
+        if (*msg_ptr & 0x80)
+        {
+          s32_t sub_id = 0;
+
+          while ((*msg_ptr & 0x80) && (len > 1))
+          {
+            len--;
+            sub_id = (sub_id << 7) + (*msg_ptr & ~0x80);
+            ofs += 1;
+            if (ofs >= plen)
+            {
+              /* next octet in next pbuf */
+              p = p->next;
+              if (p == NULL) { return ERR_ARG; }
+              msg_ptr = (u8_t*)p->payload;
+              plen += p->len;
+            }
+            else
+            {
+              /* next octet in same pbuf */
+              msg_ptr++;
+            }
+          }
+          if (!(*msg_ptr & 0x80) && (len > 0))
+          {
+            /* last octet sub-identifier */
+            len--;
+            sub_id = (sub_id << 7) + *msg_ptr;
+            *oid_ptr = sub_id;
+          }
+        }
+        else
+        {
+          /* !(*msg_ptr & 0x80) sub-identifier uses single octet */
+          len--;
+          *oid_ptr = *msg_ptr;
+        }
+        if (len > 0)
+        {
+          /* remaining oid bytes available ... */
+          ofs += 1;
+          if (ofs >= plen)
+          {
+            /* next octet in next pbuf */
+            p = p->next;
+            if (p == NULL) { return ERR_ARG; }
+            msg_ptr = (u8_t*)p->payload;
+            plen += p->len;
+          }
+          else
+          {
+            /* next octet in same pbuf */
+            msg_ptr++;
+          }
+        }
+        oid_ptr++;
+        oid->len++;
+      }
+      if (len == 0)
+      {
+        /* len == 0, end of oid */
+        return ERR_OK;
+      }
+      else
+      {
+        /* len > 0, oid->len == LWIP_SNMP_OBJ_ID_LEN or malformed encoding */
+        return ERR_ARG;
+      }
+
+    }
+    p = p->next;
+  }
+  /* p == NULL, ofs >= plen */
+  return ERR_ARG;
+}
+
+/**
+ * Decodes (copies) raw data (ip-addresses, octet strings, opaque encoding)
+ * from incoming message into array.
+ *
+ * @param p points to a pbuf holding an ASN1 coded raw data
+ * @param ofs points to the offset within the pbuf chain of the ASN1 coded raw data
+ * @param len length of the coded raw data (zero is valid, e.g. empty string!)
+ * @param raw_len length of the raw return value
+ * @param raw return raw bytes
+ * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode
+ */
+err_t
+snmp_asn1_dec_raw(struct pbuf *p, u16_t ofs, u16_t len, u16_t raw_len, u8_t *raw)
+{
+  u16_t plen, base;
+  u8_t *msg_ptr;
+
+  if (len > 0)
+  {
+    plen = 0;
+    while (p != NULL)
+    {
+      base = plen;
+      plen += p->len;
+      if (ofs < plen)
+      {
+        msg_ptr = (u8_t*)p->payload;
+        msg_ptr += ofs - base;
+        if (raw_len >= len)
+        {
+          while (len > 1)
+          {
+            /* copy len - 1 octets */
+            len--;
+            *raw = *msg_ptr;
+            raw++;
+            ofs += 1;
+            if (ofs >= plen)
+            {
+              /* next octet in next pbuf */
+              p = p->next;
+              if (p == NULL) { return ERR_ARG; }
+              msg_ptr = (u8_t*)p->payload;
+              plen += p->len;
+            }
+            else
+            {
+              /* next octet in same pbuf */
+              msg_ptr++;
+            }
+          }
+          /* copy last octet */
+          *raw = *msg_ptr;
+          return ERR_OK;
+        }
+        else
+        {
+          /* raw_len < len, not enough dst space */
+          return ERR_ARG;
+        }
+      }
+      p = p->next;
+    }
+    /* p == NULL, ofs >= plen */
+    return ERR_ARG;
+  }
+  else
+  {
+    /* len == 0, empty string */
+    return ERR_OK;
+  }
+}
+
+#endif /* LWIP_SNMP */

src/lwip-1.4.1/src/core/snmp/asn1_enc.c

@@ -0,0 +1,611 @@
+/**
+ * @file
+ * Abstract Syntax Notation One (ISO 8824, 8825) encoding
+ *
+ * @todo not optimised (yet), favor correctness over speed, favor speed over size
+ */
+
+/*
+ * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * Author: Christiaan Simons <christiaan.simons@axon.tv>
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/snmp_asn1.h"
+
+/**
+ * Returns octet count for length.
+ *
+ * @param length
+ * @param octets_needed points to the return value
+ */
+void
+snmp_asn1_enc_length_cnt(u16_t length, u8_t *octets_needed)
+{
+  if (length < 0x80U)
+  {
+    *octets_needed = 1;
+  }
+  else if (length < 0x100U)
+  {
+    *octets_needed = 2;
+  }
+  else
+  {
+    *octets_needed = 3;
+  }
+}
+
+/**
+ * Returns octet count for an u32_t.
+ *
+ * @param value
+ * @param octets_needed points to the return value
+ *
+ * @note ASN coded integers are _always_ signed. E.g. +0xFFFF is coded
+ * as 0x00,0xFF,0xFF. Note the leading sign octet. A positive value
+ * of 0xFFFFFFFF is preceded with 0x00 and the length is 5 octets!!
+ */
+void
+snmp_asn1_enc_u32t_cnt(u32_t value, u16_t *octets_needed)
+{
+  if (value < 0x80UL)
+  {
+    *octets_needed = 1;
+  }
+  else if (value < 0x8000UL)
+  {
+    *octets_needed = 2;
+  }
+  else if (value < 0x800000UL)
+  {
+    *octets_needed = 3;
+  }
+  else if (value < 0x80000000UL)
+  {
+    *octets_needed = 4;
+  }
+  else
+  {
+    *octets_needed = 5;
+  }
+}
+
+/**
+ * Returns octet count for an s32_t.
+ *
+ * @param value
+ * @param octets_needed points to the return value
+ *
+ * @note ASN coded integers are _always_ signed.
+ */
+void
+snmp_asn1_enc_s32t_cnt(s32_t value, u16_t *octets_needed)
+{
+  if (value < 0)
+  {
+    value = ~value;
+  }
+  if (value < 0x80L)
+  {
+    *octets_needed = 1;
+  }
+  else if (value < 0x8000L)
+  {
+    *octets_needed = 2;
+  }
+  else if (value < 0x800000L)
+  {
+    *octets_needed = 3;
+  }
+  else
+  {
+    *octets_needed = 4;
+  }
+}
+
+/**
+ * Returns octet count for an object identifier.
+ *
+ * @param ident_len object identifier array length
+ * @param ident points to object identifier array
+ * @param octets_needed points to the return value
+ */
+void
+snmp_asn1_enc_oid_cnt(u8_t ident_len, s32_t *ident, u16_t *octets_needed)
+{
+  s32_t sub_id;
+  u8_t cnt;
+
+  cnt = 0;
+  if (ident_len > 1)
+  {
+    /* compressed prefix in one octet */
+    cnt++;
+    ident_len -= 2;
+    ident += 2;
+  }
+  while(ident_len > 0)
+  {
+    ident_len--;
+    sub_id = *ident;
+
+    sub_id >>= 7;
+    cnt++;
+    while(sub_id > 0)
+    {
+      sub_id >>= 7;
+      cnt++;
+    }
+    ident++;
+  }
+  *octets_needed = cnt;
+}
+
+/**
+ * Encodes ASN type field into a pbuf chained ASN1 msg.
+ *
+ * @param p points to output pbuf to encode value into
+ * @param ofs points to the offset within the pbuf chain
+ * @param type input ASN1 type
+ * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
+ */
+err_t
+snmp_asn1_enc_type(struct pbuf *p, u16_t ofs, u8_t type)
+{
+  u16_t plen, base;
+  u8_t *msg_ptr;
+
+  plen = 0;
+  while (p != NULL)
+  {
+    base = plen;
+    plen += p->len;
+    if (ofs < plen)
+    {
+      msg_ptr = (u8_t*)p->payload;
+      msg_ptr += ofs - base;
+      *msg_ptr = type;
+      return ERR_OK;
+    }
+    p = p->next;
+  }
+  /* p == NULL, ofs >= plen */
+  return ERR_ARG;
+}
+
+/**
+ * Encodes host order length field into a pbuf chained ASN1 msg.
+ *
+ * @param p points to output pbuf to encode length into
+ * @param ofs points to the offset within the pbuf chain
+ * @param length is the host order length to be encoded
+ * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
+ */
+err_t
+snmp_asn1_enc_length(struct pbuf *p, u16_t ofs, u16_t length)
+{
+  u16_t plen, base;
+  u8_t *msg_ptr;
+
+  plen = 0;
+  while (p != NULL)
+  {
+    base = plen;
+    plen += p->len;
+    if (ofs < plen)
+    {
+      msg_ptr = (u8_t*)p->payload;
+      msg_ptr += ofs - base;
+
+      if (length < 0x80)
+      {
+        *msg_ptr = (u8_t)length;
+        return ERR_OK;
+      }
+      else if (length < 0x100)
+      {
+        *msg_ptr = 0x81;
+        ofs += 1;
+        if (ofs >= plen)
+        {
+          /* next octet in next pbuf */
+          p = p->next;
+          if (p == NULL) { return ERR_ARG; }
+          msg_ptr = (u8_t*)p->payload;
+        }
+        else
+        {
+          /* next octet in same pbuf */
+          msg_ptr++;
+        }
+        *msg_ptr = (u8_t)length;
+        return ERR_OK;
+      }
+      else
+      {
+        u8_t i;
+
+        /* length >= 0x100 && length <= 0xFFFF */
+        *msg_ptr = 0x82;
+        i = 2;
+        while (i > 0)
+        {
+          i--;
+          ofs += 1;
+          if (ofs >= plen)
+          {
+            /* next octet in next pbuf */
+            p = p->next;
+            if (p == NULL) { return ERR_ARG; }
+            msg_ptr = (u8_t*)p->payload;
+            plen += p->len;
+          }
+          else
+          {
+            /* next octet in same pbuf */
+            msg_ptr++;
+          }
+          if (i == 0)
+          {
+            /* least significant length octet */
+            *msg_ptr = (u8_t)length;
+          }
+          else
+          {
+            /* most significant length octet */
+            *msg_ptr = (u8_t)(length >> 8);
+          }
+        }
+        return ERR_OK;
+      }
+    }
+    p = p->next;
+  }
+  /* p == NULL, ofs >= plen */
+  return ERR_ARG;
+}
+
+/**
+ * Encodes u32_t (counter, gauge, timeticks) into a pbuf chained ASN1 msg.
+ *
+ * @param p points to output pbuf to encode value into
+ * @param ofs points to the offset within the pbuf chain
+ * @param octets_needed encoding length (from snmp_asn1_enc_u32t_cnt())
+ * @param value is the host order u32_t value to be encoded
+ * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
+ *
+ * @see snmp_asn1_enc_u32t_cnt()
+ */
+err_t
+snmp_asn1_enc_u32t(struct pbuf *p, u16_t ofs, u16_t octets_needed, u32_t value)
+{
+  u16_t plen, base;
+  u8_t *msg_ptr;
+
+  plen = 0;
+  while (p != NULL)
+  {
+    base = plen;
+    plen += p->len;
+    if (ofs < plen)
+    {
+      msg_ptr = (u8_t*)p->payload;
+      msg_ptr += ofs - base;
+
+      if (octets_needed == 5)
+      {
+        /* not enough bits in 'value' add leading 0x00 */
+        octets_needed--;
+        *msg_ptr = 0x00;
+        ofs += 1;
+        if (ofs >= plen)
+        {
+          /* next octet in next pbuf */
+          p = p->next;
+          if (p == NULL) { return ERR_ARG; }
+          msg_ptr = (u8_t*)p->payload;
+          plen += p->len;
+        }
+        else
+        {
+          /* next octet in same pbuf */
+          msg_ptr++;
+        }
+      }
+      while (octets_needed > 1)
+      {
+        octets_needed--;
+        *msg_ptr = (u8_t)(value >> (octets_needed << 3));
+        ofs += 1;
+        if (ofs >= plen)
+        {
+          /* next octet in next pbuf */
+          p = p->next;
+          if (p == NULL) { return ERR_ARG; }
+          msg_ptr = (u8_t*)p->payload;
+          plen += p->len;
+        }
+        else
+        {
+          /* next octet in same pbuf */
+          msg_ptr++;
+        }
+      }
+      /* (only) one least significant octet */
+      *msg_ptr = (u8_t)value;
+      return ERR_OK;
+    }
+    p = p->next;
+  }
+  /* p == NULL, ofs >= plen */
+  return ERR_ARG;
+}
+
+/**
+ * Encodes s32_t integer into a pbuf chained ASN1 msg.
+ *
+ * @param p points to output pbuf to encode value into
+ * @param ofs points to the offset within the pbuf chain
+ * @param octets_needed encoding length (from snmp_asn1_enc_s32t_cnt())
+ * @param value is the host order s32_t value to be encoded
+ * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
+ *
+ * @see snmp_asn1_enc_s32t_cnt()
+ */
+err_t
+snmp_asn1_enc_s32t(struct pbuf *p, u16_t ofs, u16_t octets_needed, s32_t value)
+{
+  u16_t plen, base;
+  u8_t *msg_ptr;
+
+  plen = 0;
+  while (p != NULL)
+  {
+    base = plen;
+    plen += p->len;
+    if (ofs < plen)
+    {
+      msg_ptr = (u8_t*)p->payload;
+      msg_ptr += ofs - base;
+
+      while (octets_needed > 1)
+      {
+        octets_needed--;
+        *msg_ptr = (u8_t)(value >> (octets_needed << 3));
+        ofs += 1;
+        if (ofs >= plen)
+        {
+          /* next octet in next pbuf */
+          p = p->next;
+          if (p == NULL) { return ERR_ARG; }
+          msg_ptr = (u8_t*)p->payload;
+          plen += p->len;
+        }
+        else
+        {
+          /* next octet in same pbuf */
+          msg_ptr++;
+        }
+      }
+      /* (only) one least significant octet */
+      *msg_ptr = (u8_t)value;
+      return ERR_OK;
+    }
+    p = p->next;
+  }
+  /* p == NULL, ofs >= plen */
+  return ERR_ARG;
+}
+
+/**
+ * Encodes object identifier into a pbuf chained ASN1 msg.
+ *
+ * @param p points to output pbuf to encode oid into
+ * @param ofs points to the offset within the pbuf chain
+ * @param ident_len object identifier array length
+ * @param ident points to object identifier array
+ * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
+ */
+err_t
+snmp_asn1_enc_oid(struct pbuf *p, u16_t ofs, u8_t ident_len, s32_t *ident)
+{
+  u16_t plen, base;
+  u8_t *msg_ptr;
+
+  plen = 0;
+  while (p != NULL)
+  {
+    base = plen;
+    plen += p->len;
+    if (ofs < plen)
+    {
+      msg_ptr = (u8_t*)p->payload;
+      msg_ptr += ofs - base;
+
+      if (ident_len > 1)
+      {
+        if ((ident[0] == 1) && (ident[1] == 3))
+        {
+          /* compressed (most common) prefix .iso.org */
+          *msg_ptr = 0x2b;
+        }
+        else
+        {
+          /* calculate prefix */
+          *msg_ptr = (u8_t)((ident[0] * 40) + ident[1]);
+        }
+        ofs += 1;
+        if (ofs >= plen)
+        {
+          /* next octet in next pbuf */
+          p = p->next;
+          if (p == NULL) { return ERR_ARG; }
+          msg_ptr = (u8_t*)p->payload;
+          plen += p->len;
+        }
+        else
+        {
+          /* next octet in same pbuf */
+          msg_ptr++;
+        }
+        ident_len -= 2;
+        ident += 2;
+      }
+      else
+      {
+/* @bug:  allow empty varbinds for symmetry (we must decode them for getnext), allow partial compression??  */
+        /* ident_len <= 1, at least we need zeroDotZero (0.0) (ident_len == 2) */
+        return ERR_ARG;
+      }
+      while (ident_len > 0)
+      {
+        s32_t sub_id;
+        u8_t shift, tail;
+
+        ident_len--;
+        sub_id = *ident;
+        tail = 0;
+        shift = 28;
+        while(shift > 0)
+        {
+          u8_t code;
+
+          code = (u8_t)(sub_id >> shift);
+          if ((code != 0) || (tail != 0))
+          {
+            tail = 1;
+            *msg_ptr = code | 0x80;
+            ofs += 1;
+            if (ofs >= plen)
+            {
+              /* next octet in next pbuf */
+              p = p->next;
+              if (p == NULL) { return ERR_ARG; }
+              msg_ptr = (u8_t*)p->payload;
+              plen += p->len;
+            }
+            else
+            {
+              /* next octet in same pbuf */
+              msg_ptr++;
+            }
+          }
+          shift -= 7;
+        }
+        *msg_ptr = (u8_t)sub_id & 0x7F;
+        if (ident_len > 0)
+        {
+          ofs += 1;
+          if (ofs >= plen)
+          {
+            /* next octet in next pbuf */
+            p = p->next;
+            if (p == NULL) { return ERR_ARG; }
+            msg_ptr = (u8_t*)p->payload;
+            plen += p->len;
+          }
+          else
+          {
+            /* next octet in same pbuf */
+            msg_ptr++;
+          }
+        }
+        /* proceed to next sub-identifier */
+        ident++;
+      }
+      return ERR_OK;
+    }
+    p = p->next;
+  }
+  /* p == NULL, ofs >= plen */
+  return ERR_ARG;
+}
+
+/**
+ * Encodes raw data (octet string, opaque) into a pbuf chained ASN1 msg.
+ *
+ * @param p points to output pbuf to encode raw data into
+ * @param ofs points to the offset within the pbuf chain
+ * @param raw_len raw data length
+ * @param raw points raw data
+ * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
+ */
+err_t
+snmp_asn1_enc_raw(struct pbuf *p, u16_t ofs, u16_t raw_len, u8_t *raw)
+{
+  u16_t plen, base;
+  u8_t *msg_ptr;
+
+  plen = 0;
+  while (p != NULL)
+  {
+    base = plen;
+    plen += p->len;
+    if (ofs < plen)
+    {
+      msg_ptr = (u8_t*)p->payload;
+      msg_ptr += ofs - base;
+
+      while (raw_len > 1)
+      {
+        /* copy raw_len - 1 octets */
+        raw_len--;
+        *msg_ptr = *raw;
+        raw++;
+        ofs += 1;
+        if (ofs >= plen)
+        {
+          /* next octet in next pbuf */
+          p = p->next;
+          if (p == NULL) { return ERR_ARG; }
+          msg_ptr = (u8_t*)p->payload;
+          plen += p->len;
+        }
+        else
+        {
+          /* next octet in same pbuf */
+          msg_ptr++;
+        }
+      }
+      if (raw_len > 0)
+      {
+        /* copy last or single octet */
+        *msg_ptr = *raw;
+      }
+      return ERR_OK;
+    }
+    p = p->next;
+  }
+  /* p == NULL, ofs >= plen */
+  return ERR_ARG;
+}
+
+#endif /* LWIP_SNMP */