zebra/rtread_sysctl.c

   1 /*
   2  * Kernel routing table read by sysctl function.
   3  * Copyright (C) 1997, 98 Kunihiro Ishiguro
   4  *
   5  * This file is part of GNU Zebra.
   6  *
   7  * GNU Zebra is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2, or (at your option) any
  10  * later version.
  11  *
  12  * GNU Zebra is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with GNU Zebra; see the file COPYING.  If not, write to the Free
  19  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  20  * 02111-1307, USA.
  21  */
  22
  23 #include <zebra.h>
  24
  25 #include "memory.h"
  26 #include "log.h"
  27
  28 #include "zebra/zserv.h"
  29 #include "zebra/rt.h"
  30 #include "zebra/kernel_socket.h"
  31
  32 /* Kernel routing table read up by sysctl function. */
  33 void
  34 route_read (void)
  35 {
  36   caddr_t buf, end, ref;
  37   size_t bufsiz;
  38   struct rt_msghdr *rtm;
  39
  40 #define MIBSIZ 6
  41   int mib[MIBSIZ] =
  42   {
  43     CTL_NET,
  44     PF_ROUTE,
  45     0,
  46     0,
  47     NET_RT_DUMP,
  48     0
  49   };
  50
  51   /* Get buffer size. */
  52   if (sysctl (mib, MIBSIZ, NULL, &bufsiz, NULL, 0) < 0)
  53     {
  54       zlog_warn ("sysctl fail: %s", safe_strerror (errno));
  55       return;
  56     }
  57
  58   /* Allocate buffer. */
  59   ref = buf = XMALLOC (MTYPE_TMP, bufsiz);
  60
  61   /* Read routing table information by calling sysctl(). */
  62   if (sysctl (mib, MIBSIZ, buf, &bufsiz, NULL, 0) < 0)
  63     {
  64       zlog_warn ("sysctl() fail by %s", safe_strerror (errno));
  65       return;
  66     }
  67
  68   for (end = buf + bufsiz; buf < end; buf += rtm->rtm_msglen)
  69     {
  70       rtm = (struct rt_msghdr *) buf;
  71       /* We must set RTF_DONE here, so rtm_read() doesn't ignore the message. */
  72       SET_FLAG (rtm->rtm_flags, RTF_DONE);
  73       rtm_read (rtm);
  74     }
  75
  76   /* Free buffer. */
  77   XFREE (MTYPE_TMP, ref);
  78
  79   return;
  80 }