Add rtems_get_route to fetch a specific route from the routing tables.

libbsd.py

@@ -105,6 +105,7 @@ def rtems(mm):
             'rtems/rtems-legacy-newproc.c',
             'rtems/rtems-legacy-mii.c',
             'rtems/rtems-kvm.c',
+            'rtems/rtems-routes.c',
             'rtems/syslog.c',
             'ftpd/ftpd.c',
             'ftpd/ftpd-init.c',

libbsd_waf.py

@@ -1098,6 +1098,7 @@ def build(bld):
               'rtemsbsd/rtems/rtems-legacy-mii.c',
               'rtemsbsd/rtems/rtems-legacy-newproc.c',
               'rtemsbsd/rtems/rtems-legacy-rtrequest.c',
+              'rtemsbsd/rtems/rtems-routes.c',
               'rtemsbsd/rtems/syslog.c',
               'rtemsbsd/sys/dev/dw_mmc/dw_mmc.c',
               'rtemsbsd/sys/dev/ffec/if_ffec_mcf548x.c',

rtemsbsd/include/rtems/rtems-routes.h

@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2016 Chris Johns <chrisj@rtems.org>.  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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 THE AUTHOR 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.
+ */
+
+#ifndef RTEMS_ROUTES_h
+#define RTEMS_ROUTES_h
+
+#include <sys/socket.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/*
+ * Useful functions to access the routing tables.
+ */
+
+/*
+ * Get a route. The array size of sockadd's must be RTAX_MAX.
+ */
+int rtems_get_route(const struct sockaddr_in* sin, struct sockaddr** rti_info);
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* RTEMS_ROUTES_h */

rtemsbsd/rtems/rtems-routes.c

@@ -0,0 +1,141 @@
+/*
+ * Copyright (c) 2016 Chris Johns <chrisj@rtems.org>.  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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 THE AUTHOR 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.
+ */
+
+/*
+ * Useful functions to access the routing tables. Based on unpv13e from
+ * Stevens.
+ */
+
+#include <stdbool.h>
+#include <errno.h>
+
+#include <net/if.h>
+#include <net/route.h>
+#include <netinet/in.h>
+#include <sys/socket.h>
+
+/*
+ * Round up 'a' to next multiple of 'size', which must be a power of 2
+ */
+#define RR_ROUNDUP(a, size) (((a) & ((size)-1)) ? (1 + ((a) | ((size)-1))) : (a))
+
+/*
+ * Step to next socket address structure;
+ * if sa_len is 0, assume it is sizeof(u_long).
+ */
+#define NEXT_SA(ap)							\
+  ap = (struct sockaddr*) ((caddr_t) ap +				\
+			   (ap->sa_len ? RR_ROUNDUP(ap->sa_len, sizeof (u_long)) : sizeof(u_long)))
+
+static void
+get_rtaddrs(int addrs, struct sockaddr* sa, struct sockaddr** rti_info)
+{
+  int i;
+
+  for (i = 0; i < RTAX_MAX; i++) {
+    if ((addrs & (1 << i)) != 0) {
+      rti_info[i] = sa;
+      NEXT_SA(sa);
+    } else
+      rti_info[i] = NULL;
+  }
+}
+
+/*
+ * Get a route.
+ */
+int rtems_get_route(const struct sockaddr_in* sin, struct sockaddr** rti_info)
+{
+  int                 s;
+  char*               buf;
+  const size_t        buflen = sizeof(struct rt_msghdr) + 512;
+  pid_t               pid;
+  struct rt_msghdr*   rtm;
+  struct sockaddr_in* r_sin;
+  struct sockaddr*    sa;
+  const int           seq = (int) 0x28290817;
+  ssize_t             r;
+
+  buf = calloc(1, buflen);
+  if (buf == NULL) {
+    errno = ENOMEM;
+    return -1;
+  }
+
+  s = socket(AF_ROUTE, SOCK_RAW, AF_UNSPEC);
+  if (s < 0)
+    return -1;
+
+  rtm = (struct rt_msghdr *) buf;
+  rtm->rtm_msglen = sizeof(struct rt_msghdr) + sizeof(struct sockaddr_in);
+  rtm->rtm_version = RTM_VERSION;
+  rtm->rtm_type = RTM_GET;
+  rtm->rtm_addrs = RTA_DST;
+  rtm->rtm_pid = pid = getpid();
+  rtm->rtm_seq = seq;
+
+  r_sin = (struct sockaddr_in *) (rtm + 1);
+  *r_sin = *sin;
+
+  r = write(s, rtm, rtm->rtm_msglen);
+  if (r < 0) {
+    int en = errno;
+    close(s);
+    free(buf);
+    errno = en;
+    return -1;
+  }
+
+  while (true) {
+    r = read(s, rtm, buflen);
+    if (r < 0) {
+      int en = errno;
+      close(s);
+      free(buf);
+      errno = en;
+      return -1;
+    }
+
+    /*
+     * The kernel sends all routing message to all routing sockets. We need to
+     * filter them for the one for us.
+     */
+    if (rtm->rtm_type == RTM_GET &&
+	rtm->rtm_seq == seq &&
+	rtm->rtm_pid == pid)
+      break;
+  }
+
+  close(s);
+
+  rtm = (struct rt_msghdr*) buf;
+  sa = (struct sockaddr*) (rtm + 1);
+
+  get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
+
+  free(buf);
+
+  return 0;
+}