openwrt/dnsmasq
1
0
Fork 0
mirror of https://github.com/infinet/dnsmasq.git synced 2025-05-08 00:56:06 +08:00
Code Issues Releases Wiki Activity

Add RFC4039 rapid commit support.

Browse Source
This commit is contained in:
Simon Kelley 2018-03-23 23:09:53 +00:00
parent 9a7be47614
commit 734d53176f
8 changed files with 49 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
CHANGELOG
View File

@ -1,3 +1,8 @@
version 2.80
Add support for RFC 4039 DHCP rapid commit. Thanks to Ashram Method
for the initial patch and motivation.
version 2.79
Fix parsing of CNAME arguments, which are confused by extra spaces.
Thanks to Diego Aguirre for spotting the bug.

8
dnsmasq.conf.example
View File

@ -547,6 +547,14 @@
# http://www.isc.org/files/auth.html
#dhcp-authoritative
# Set the DHCP server to enable DHCPv4 Rapid Commit Option per RFC 4039.
# In this mode it will respond to a DHCPDISCOVER message including a Rapid Commit
# option with a DHCPACK including a Rapid Commit option and fully committed address
# and configuration information. This must only be enabled if either the server is
# the only server for the subnet, or multiple servers are present and they each
# commit a binding for all clients.
#dhcp-rapid-commit
# Run an executable when a DHCP lease is created or destroyed.
# The arguments sent to the script are "add" or "del",
# then the MAC address, the IP address and finally the hostname

7
man/dnsmasq.8
View File

@ -1452,6 +1452,13 @@ allows dnsmasq to rebuild its lease database without each client needing to
reacquire a lease, if the database is lost. For DHCPv6 it sets the
priority in replies to 255 (the maximum) instead of 0 (the minimum).
.TP
.B --dhcp-rapid-commit
Enable DHCPv4 Rapid Commit Option specified in RFC 4039. When enabled, dnsmasq
will respond to a DHCPDISCOVER message including a Rapid Commit
option with a DHCPACK including a Rapid Commit option and fully committed
address and configuration information. Should only be enabled if either the
server is the only server for the subnet, or multiple servers are present and they each commit a binding for all clients.
.TP
.B --dhcp-alternate-port[=<server port>[,<client port>]]
(IPv4 only) Change the ports used for DHCP from the default. If this option is
given alone, without arguments, it changes the ports used for DHCP

1
src/dhcp-common.c
View File

@ -556,6 +556,7 @@ static const struct opttab_t {
{ "nntp-server", 71, OT_ADDR_LIST },
{ "irc-server", 74, OT_ADDR_LIST },
{ "user-class", 77, 0 },
{ "rapid-commit", 80, 0 },
{ "FQDN", 81, OT_INTERNAL },
{ "agent-id", 82, OT_INTERNAL },
{ "client-arch", 93, 2 | OT_DEC },

1
src/dhcp-protocol.h
View File

@ -54,6 +54,7 @@
#define OPTION_SNAME 66
#define OPTION_FILENAME 67
#define OPTION_USER_CLASS 77
#define OPTION_RAPID_COMMIT 80
#define OPTION_CLIENT_FQDN 81
#define OPTION_AGENT_ID 82
#define OPTION_ARCH 93

3
src/dnsmasq.h
View File

@ -250,7 +250,8 @@ struct event_desc {
#define OPT_MAC_B64 54
#define OPT_MAC_HEX 55
#define OPT_TFTP_APREF_MAC 56
#define OPT_LAST 57
#define OPT_RAPID_COMMIT 57
#define OPT_LAST 58
/* extra flags for my_syslog, we use a couple of facilities since they are known
not to occupy the same bits as priorities, no matter how syslog.h is set up. */

3
src/option.c
View File

@ -160,6 +160,7 @@ struct myoption {
#define LOPT_DHCPTTL 348
#define LOPT_TFTP_MTU 349
#define LOPT_REPLY_DELAY 350
#define LOPT_RAPID_COMMIT 351
#ifdef HAVE_GETOPT_LONG
static const struct option opts[] =
@ -325,6 +326,7 @@ static const struct myoption opts[] =
{ "script-arp", 0, 0, LOPT_SCRIPT_ARP },
{ "dhcp-ttl", 1, 0 , LOPT_DHCPTTL },
{ "dhcp-reply-delay", 1, 0, LOPT_REPLY_DELAY },
{ "dhcp-rapid-commit", 0, 0, LOPT_RAPID_COMMIT },
{ NULL, 0, 0, 0 }
};
@ -497,6 +499,7 @@ static struct {
{ LOPT_IGNORE_ADDR, ARG_DUP, "<ipaddr>", gettext_noop("Ignore DNS responses containing ipaddr."), NULL },
{ LOPT_DHCPTTL, ARG_ONE, "<ttl>", gettext_noop("Set TTL in DNS responses with DHCP-derived addresses."), NULL },
{ LOPT_REPLY_DELAY, ARG_ONE, "<integer>", gettext_noop("Delay DHCP replies for at least number of seconds."), NULL },
{ LOPT_RAPID_COMMIT, OPT_RAPID_COMMIT, NULL, gettext_noop("Enables DHCPv4 Rapid Commit option."), NULL },
{ 0, 0, NULL, NULL, NULL }
};

29
src/rfc2131.c
View File

@ -75,7 +75,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
struct dhcp_vendor *vendor;
struct dhcp_mac *mac;
struct dhcp_netid_list *id_list;
int clid_len = 0, ignore = 0, do_classes = 0, selecting = 0, pxearch = -1;
int clid_len = 0, ignore = 0, do_classes = 0, rapid_commit = 0, selecting = 0, pxearch = -1;
struct dhcp_packet *mess = (struct dhcp_packet *)daemon->dhcp_packet.iov_base;
unsigned char *end = (unsigned char *)(mess + 1);
unsigned char *real_end = (unsigned char *)(mess + 1);
@ -1073,6 +1073,13 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
log_tags(tagif_netid, ntohl(mess->xid));
apply_delay(mess->xid, recvtime, tagif_netid);
if (option_bool(OPT_RAPID_COMMIT) && option_find(mess, sz, OPTION_RAPID_COMMIT, 0))
{
rapid_commit = 1;
goto rapid_commit;
}
log_packet("DHCPOFFER" , &mess->yiaddr, emac, emac_len, iface_name, NULL, NULL, mess->xid);
time = calc_time(context, config, option_find(mess, sz, OPTION_LEASE_TIME, 4));
@ -1085,7 +1092,8 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
netid, subnet_addr, fqdn_flags, borken_opt, pxearch, uuid, vendor_class_len, now, time, fuzz);
return dhcp_packet_size(mess, agent_id, real_end);
case DHCPREQUEST:
if (ignore || have_config(config, CONFIG_DISABLE))
return 0;
@ -1183,9 +1191,10 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
fuzz = rand16();
mess->yiaddr = mess->ciaddr;
}
log_packet("DHCPREQUEST", &mess->yiaddr, emac, emac_len, iface_name, NULL, NULL, mess->xid);
rapid_commit:
if (!message)
{
struct dhcp_config *addr_config;
@ -1256,7 +1265,11 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
if (message)
{
log_packet("DHCPNAK", &mess->yiaddr, emac, emac_len, iface_name, NULL, message, mess->xid);
log_packet(rapid_commit ? "NOANSWER" : "DHCPNAK", &mess->yiaddr, emac, emac_len, iface_name, NULL, message, mess->xid);
/* rapid commit case: lease allocate failed but don't send DHCPNAK */
if (rapid_commit)
return 0;
mess->yiaddr.s_addr = 0;
clear_packet(mess, end);
@ -1414,12 +1427,14 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
override = lease->override;
log_packet("DHCPACK", &mess->yiaddr, emac, emac_len, iface_name, hostname, NULL, mess->xid);
clear_packet(mess, end);
option_put(mess, end, OPTION_MESSAGE_TYPE, 1, DHCPACK);
option_put(mess, end, OPTION_SERVER_IDENTIFIER, INADDRSZ, ntohl(server_id(context, override, fallback).s_addr));
option_put(mess, end, OPTION_LEASE_TIME, 4, time);
do_options(context, mess, end, req_options, hostname, get_domain(mess->yiaddr),
if (rapid_commit)
option_put(mess, end, OPTION_RAPID_COMMIT, 0, 0);
do_options(context, mess, end, req_options, hostname, get_domain(mess->yiaddr),
netid, subnet_addr, fqdn_flags, borken_opt, pxearch, uuid, vendor_class_len, now, time, fuzz);
}