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 along
  18  * with this program; see the file COPYING; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include <zebra.h>
  23
  24 #include "memory.h"
  25 #include "zebra_memory.h"
  26 #include "log.h"
  27 #include "vrf.h"
  28
  29 #include "zebra/zserv.h"
  30 #include "zebra/rt.h"
  31 #include "zebra/kernel_socket.h"
  32
  33 /* Kernel routing table read up by sysctl function. */
  34 void
  35 route_read (struct zebra_ns *zns)
  36 {
  37   caddr_t buf, end, ref;
  38   size_t bufsiz;
  39   struct rt_msghdr *rtm;
  40
  41 #define MIBSIZ 6
  42   int mib[MIBSIZ] =
  43   {
  44     CTL_NET,
  45     PF_ROUTE,
  46     0,
  47     0,
  48     NET_RT_DUMP,
  49     0
  50   };
  51
  52   if (zns->ns_id != NS_DEFAULT)
  53     return;
  54
  55   /* Get buffer size. */
  56   if (sysctl (mib, MIBSIZ, NULL, &bufsiz, NULL, 0) < 0)
  57     {
  58       zlog_warn ("sysctl fail: %s", safe_strerror (errno));
  59       return;
  60     }
  61
  62   /* Allocate buffer. */
  63   ref = buf = XMALLOC (MTYPE_TMP, bufsiz);
  64
  65   /* Read routing table information by calling sysctl(). */
  66   if (sysctl (mib, MIBSIZ, buf, &bufsiz, NULL, 0) < 0)
  67     {
  68       zlog_warn ("sysctl() fail by %s", safe_strerror (errno));
  69       XFREE(MTYPE_TMP, ref);
  70       return;
  71     }
  72
  73   for (end = buf + bufsiz; buf < end; buf += rtm->rtm_msglen)
  74     {
  75       rtm = (struct rt_msghdr *) buf;
  76       /* We must set RTF_DONE here, so rtm_read() doesn't ignore the message. */
  77       SET_FLAG (rtm->rtm_flags, RTF_DONE);
  78       rtm_read (rtm);
  79     }
  80
  81   /* Free buffer. */
  82   XFREE (MTYPE_TMP, ref);
  83
  84   return;
  85 }