zebra/rt_ioctl.c - quagga - Gitiles

 /*
  * kernel routing table update by ioctl().
  * Copyright (C) 1997, 98 Kunihiro Ishiguro
  *
  * This file is part of GNU Zebra.
  *
  * GNU Zebra is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by the
  * Free Software Foundation; either version 2, or (at your option) any
  * later version.
  *
  * GNU Zebra is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with GNU Zebra; see the file COPYING.  If not, write to the Free
  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  * 02111-1307, USA.
  */

 #include <zebra.h>

 #include "prefix.h"
 #include "log.h"
 #include "if.h"

 #include "zebra/zserv.h"
 #include "zebra/rib.h"
 #include "zebra/debug.h"
 #include "zebra/rt.h"

 /* Initialize of kernel interface.  There is no kernel communication
    support under ioctl().  So this is dummy stub function. */
 void
 kernel_init (void)
 {
   return;
 }

 /* Dummy function of routing socket. */
 static void
 kernel_read (int sock)
 {
   return;
 }

 #if 0
 /* Initialization prototype of struct sockaddr_in. */
 static struct sockaddr_in sin_proto =
 {
 #ifdef HAVE_SIN_LEN
   sizeof (struct sockaddr_in),
 #endif /* HAVE_SIN_LEN */
   AF_INET, 0, {0}, {0}
 };
 #endif /* 0 */

 /* Solaris has ortentry. */
 #ifdef HAVE_OLD_RTENTRY
 #define rtentry ortentry
 #endif /* HAVE_OLD_RTENTRY */

 /* Interface to ioctl route message. */
 int
 kernel_add_route (struct prefix_ipv4 *dest, struct in_addr *gate,
 		  int index, int flags)
 {
   int ret;
   int sock;
   struct rtentry rtentry;
   struct sockaddr_in sin_dest, sin_mask, sin_gate;

   memset (&rtentry, 0, sizeof (struct rtentry));

   /* Make destination. */
   memset (&sin_dest, 0, sizeof (struct sockaddr_in));
   sin_dest.sin_family = AF_INET;
 #ifdef HAVE_SIN_LEN
   sin_dest.sin_len = sizeof (struct sockaddr_in);
 #endif /* HAVE_SIN_LEN */
   sin_dest.sin_addr = dest->prefix;

   /* Make gateway. */
   if (gate)
     {
       memset (&sin_gate, 0, sizeof (struct sockaddr_in));
       sin_gate.sin_family = AF_INET;
 #ifdef HAVE_SIN_LEN
       sin_gate.sin_len = sizeof (struct sockaddr_in);
 #endif /* HAVE_SIN_LEN */
       sin_gate.sin_addr = *gate;
     }

   memset (&sin_mask, 0, sizeof (struct sockaddr_in));
   sin_mask.sin_family = AF_INET;
 #ifdef HAVE_SIN_LEN
       sin_gate.sin_len = sizeof (struct sockaddr_in);
 #endif /* HAVE_SIN_LEN */
   masklen2ip (dest->prefixlen, &sin_mask.sin_addr);

   /* Set destination address, mask and gateway.*/
   memcpy (&rtentry.rt_dst, &sin_dest, sizeof (struct sockaddr_in));
   if (gate)
     memcpy (&rtentry.rt_gateway, &sin_gate, sizeof (struct sockaddr_in));
 #ifndef SUNOS_5
   memcpy (&rtentry.rt_genmask, &sin_mask, sizeof (struct sockaddr_in));
 #endif /* SUNOS_5 */

   /* Routing entry flag set. */
   if (dest->prefixlen == 32)
     rtentry.rt_flags |= RTF_HOST;

   if (gate && gate->s_addr != INADDR_ANY)
     rtentry.rt_flags |= RTF_GATEWAY;

   rtentry.rt_flags |= RTF_UP;

   /* Additional flags */
   rtentry.rt_flags |= flags;


   /* For tagging route. */
   /* rtentry.rt_flags |= RTF_DYNAMIC; */

   /* Open socket for ioctl. */
   sock = socket (AF_INET, SOCK_DGRAM, 0);
   if (sock < 0)
     {
       zlog_warn ("can't make socket\n");
       return -1;
     }

   /* Send message by ioctl(). */
   ret = ioctl (sock, SIOCADDRT, &rtentry);
   if (ret < 0)
     {
       switch (errno)
 	{
 	case EEXIST:
 	  close (sock);
 	  return ZEBRA_ERR_RTEXIST;
 	  break;
 	case ENETUNREACH:
 	  close (sock);
 	  return ZEBRA_ERR_RTUNREACH;
 	  break;
 	case EPERM:
 	  close (sock);
 	  return ZEBRA_ERR_EPERM;
 	  break;
 	}

       close (sock);
       zlog_warn ("write : %s (%d)", safe_strerror (errno), errno);
       return 1;
     }
   close (sock);

   return ret;
 }

 /* Interface to ioctl route message. */
 static int
 kernel_ioctl_ipv4 (u_long cmd, struct prefix *p, struct rib *rib, int family)
 {
   int ret;
   int sock;
   struct rtentry rtentry;
   struct sockaddr_in sin_dest, sin_mask, sin_gate;
   struct nexthop *nexthop;
   int nexthop_num = 0;
   struct interface *ifp;

   memset (&rtentry, 0, sizeof (struct rtentry));

   /* Make destination. */
   memset (&sin_dest, 0, sizeof (struct sockaddr_in));
   sin_dest.sin_family = AF_INET;
 #ifdef HAVE_SIN_LEN
   sin_dest.sin_len = sizeof (struct sockaddr_in);
 #endif /* HAVE_SIN_LEN */
   sin_dest.sin_addr = p->u.prefix4;

   if (CHECK_FLAG (rib->flags, ZEBRA_FLAG_BLACKHOLE))
     {
       SET_FLAG (rtentry.rt_flags, RTF_REJECT);

       if (cmd == SIOCADDRT)
 	for (nexthop = rib->nexthop; nexthop; nexthop = nexthop->next)
 	  SET_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB);

       goto skip;
     }

   memset (&sin_gate, 0, sizeof (struct sockaddr_in));

   /* Make gateway. */
   for (nexthop = rib->nexthop; nexthop; nexthop = nexthop->next)
     {
       if ((cmd == SIOCADDRT
 	   && CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_ACTIVE))
 	  || (cmd == SIOCDELRT
 	      && CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB)))
 	{
 	  if (CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_RECURSIVE))
 	    {
 	      if (nexthop->rtype == NEXTHOP_TYPE_IPV4 ||
 		  nexthop->rtype == NEXTHOP_TYPE_IPV4_IFINDEX)
 		{
 		  sin_gate.sin_family = AF_INET;
 #ifdef HAVE_SIN_LEN
 		  sin_gate.sin_len = sizeof (struct sockaddr_in);
 #endif /* HAVE_SIN_LEN */
 		  sin_gate.sin_addr = nexthop->rgate.ipv4;
 		  rtentry.rt_flags |= RTF_GATEWAY;
 		}
 	      if (nexthop->rtype == NEXTHOP_TYPE_IFINDEX
 		  || nexthop->rtype == NEXTHOP_TYPE_IFNAME)
 		{
 		  ifp = if_lookup_by_index (nexthop->rifindex);
 		  if (ifp)
 		    rtentry.rt_dev = ifp->name;
 		  else
 		    return -1;
 		}
 	    }
 	  else
 	    {
 	      if (nexthop->type == NEXTHOP_TYPE_IPV4 ||
 		  nexthop->type == NEXTHOP_TYPE_IPV4_IFINDEX)
 		{
 		  sin_gate.sin_family = AF_INET;
 #ifdef HAVE_SIN_LEN
 		  sin_gate.sin_len = sizeof (struct sockaddr_in);
 #endif /* HAVE_SIN_LEN */
 		  sin_gate.sin_addr = nexthop->gate.ipv4;
 		  rtentry.rt_flags |= RTF_GATEWAY;
 		}
 	      if (nexthop->type == NEXTHOP_TYPE_IFINDEX
 		  || nexthop->type == NEXTHOP_TYPE_IFNAME)
 		{
 		  ifp = if_lookup_by_index (nexthop->ifindex);
 		  if (ifp)
 		    rtentry.rt_dev = ifp->name;
 		  else
 		    return -1;
 		}
 	    }

 	  if (cmd == SIOCADDRT)
 	    SET_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB);

 	  nexthop_num++;
 	  break;
 	}
     }

   /* If there is no useful nexthop then return. */
   if (nexthop_num == 0)
     {
       if (IS_ZEBRA_DEBUG_KERNEL)
 	zlog_debug ("netlink_route_multipath(): No useful nexthop.");
       return 0;
     }

  skip:

   memset (&sin_mask, 0, sizeof (struct sockaddr_in));
   sin_mask.sin_family = AF_INET;
 #ifdef HAVE_SIN_LEN
   sin_mask.sin_len = sizeof (struct sockaddr_in);
 #endif /* HAVE_SIN_LEN */
   masklen2ip (p->prefixlen, &sin_mask.sin_addr);

   /* Set destination address, mask and gateway.*/
   memcpy (&rtentry.rt_dst, &sin_dest, sizeof (struct sockaddr_in));

   if (rtentry.rt_flags & RTF_GATEWAY)
     memcpy (&rtentry.rt_gateway, &sin_gate, sizeof (struct sockaddr_in));

 #ifndef SUNOS_5
   memcpy (&rtentry.rt_genmask, &sin_mask, sizeof (struct sockaddr_in));
 #endif /* SUNOS_5 */

   /* Metric.  It seems metric minus one value is installed... */
   rtentry.rt_metric = rib->metric;

   /* Routing entry flag set. */
   if (p->prefixlen == 32)
     rtentry.rt_flags |= RTF_HOST;

   rtentry.rt_flags |= RTF_UP;

   /* Additional flags */
   /* rtentry.rt_flags |= flags; */

   /* For tagging route. */
   /* rtentry.rt_flags |= RTF_DYNAMIC; */

   /* Open socket for ioctl. */
   sock = socket (AF_INET, SOCK_DGRAM, 0);
   if (sock < 0)
     {
       zlog_warn ("can't make socket\n");
       return -1;
     }

   /* Send message by ioctl(). */
   ret = ioctl (sock, cmd, &rtentry);
   if (ret < 0)
     {
       switch (errno)
 	{
 	case EEXIST:
 	  close (sock);
 	  return ZEBRA_ERR_RTEXIST;
 	  break;
 	case ENETUNREACH:
 	  close (sock);
 	  return ZEBRA_ERR_RTUNREACH;
 	  break;
 	case EPERM:
 	  close (sock);
 	  return ZEBRA_ERR_EPERM;
 	  break;
 	}

       close (sock);
       zlog_warn ("write : %s (%d)", safe_strerror (errno), errno);
       return ret;
     }
   close (sock);

   return ret;
 }

 int
 kernel_add_ipv4 (struct prefix *p, struct rib *rib)
 {
   return kernel_ioctl_ipv4 (SIOCADDRT, p, rib, AF_INET);
 }

 int
 kernel_delete_ipv4 (struct prefix *p, struct rib *rib)
 {
   return kernel_ioctl_ipv4 (SIOCDELRT, p, rib, AF_INET);
 }

 #ifdef HAVE_IPV6

 /* Below is hack for GNU libc definition and Linux 2.1.X header. */
 #undef RTF_DEFAULT
 #undef RTF_ADDRCONF

 #include <asm/types.h>

 #if defined(__GLIBC__) && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 1
 /* struct in6_rtmsg will be declared in net/route.h. */
 #else
 #include <linux/ipv6_route.h>
 #endif

 static int
 kernel_ioctl_ipv6 (u_long type, struct prefix_ipv6 *dest, struct in6_addr *gate,
 		   int index, int flags)
 {
   int ret;
   int sock;
   struct in6_rtmsg rtm;

   memset (&rtm, 0, sizeof (struct in6_rtmsg));

   rtm.rtmsg_flags |= RTF_UP;
   rtm.rtmsg_metric = 1;
   memcpy (&rtm.rtmsg_dst, &dest->prefix, sizeof (struct in6_addr));
   rtm.rtmsg_dst_len = dest->prefixlen;

   /* We need link local index. But this should be done caller...
   if (IN6_IS_ADDR_LINKLOCAL(&rtm.rtmsg_gateway))
     {
       index = if_index_address (&rtm.rtmsg_gateway);
       rtm.rtmsg_ifindex = index;
     }
   else
     rtm.rtmsg_ifindex = 0;
   */

   rtm.rtmsg_flags |= RTF_GATEWAY;

   /* For tagging route. */
   /* rtm.rtmsg_flags |= RTF_DYNAMIC; */

   memcpy (&rtm.rtmsg_gateway, gate, sizeof (struct in6_addr));

   if (index)
     rtm.rtmsg_ifindex = index;
   else
     rtm.rtmsg_ifindex = 0;

   rtm.rtmsg_metric = 1;

   sock = socket (AF_INET6, SOCK_DGRAM, 0);
   if (sock < 0)
     {
       zlog_warn ("can't make socket\n");
       return -1;
     }

   /* Send message via ioctl. */
   ret = ioctl (sock, type, &rtm);
   if (ret < 0)
     {
       zlog_warn ("can't %s ipv6 route: %s\n", type == SIOCADDRT ? "add" : "delete",
 	   safe_strerror(errno));
       ret = errno;
       close (sock);
       return ret;
     }
   close (sock);

   return ret;
 }

 static int
 kernel_ioctl_ipv6_multipath (u_long cmd, struct prefix *p, struct rib *rib,
 			     int family)
 {
   int ret;
   int sock;
   struct in6_rtmsg rtm;
   struct nexthop *nexthop;
   int nexthop_num = 0;

   memset (&rtm, 0, sizeof (struct in6_rtmsg));

   rtm.rtmsg_flags |= RTF_UP;
   rtm.rtmsg_metric = rib->metric;
   memcpy (&rtm.rtmsg_dst, &p->u.prefix, sizeof (struct in6_addr));
   rtm.rtmsg_dst_len = p->prefixlen;

   /* We need link local index. But this should be done caller...
   if (IN6_IS_ADDR_LINKLOCAL(&rtm.rtmsg_gateway))
     {
       index = if_index_address (&rtm.rtmsg_gateway);
       rtm.rtmsg_ifindex = index;
     }
   else
     rtm.rtmsg_ifindex = 0;
   */

   rtm.rtmsg_flags |= RTF_GATEWAY;

   /* For tagging route. */
   /* rtm.rtmsg_flags |= RTF_DYNAMIC; */

   /* Make gateway. */
   for (nexthop = rib->nexthop; nexthop; nexthop = nexthop->next)
     {
       if ((cmd == SIOCADDRT
 	   && CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_ACTIVE))
 	  || (cmd == SIOCDELRT
 	      && CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB)))
 	{
 	  if (CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_RECURSIVE))
 	    {
 	      if (nexthop->rtype == NEXTHOP_TYPE_IPV6
 		  || nexthop->rtype == NEXTHOP_TYPE_IPV6_IFNAME
 		  || nexthop->rtype == NEXTHOP_TYPE_IPV6_IFINDEX)
 		{
 		  memcpy (&rtm.rtmsg_gateway, &nexthop->rgate.ipv6,
 			  sizeof (struct in6_addr));
 		}
 	      if (nexthop->rtype == NEXTHOP_TYPE_IFINDEX
 		  || nexthop->rtype == NEXTHOP_TYPE_IFNAME
 		  || nexthop->rtype == NEXTHOP_TYPE_IPV6_IFNAME
 		  || nexthop->rtype == NEXTHOP_TYPE_IPV6_IFINDEX)
 		rtm.rtmsg_ifindex = nexthop->rifindex;
 	      else
 		rtm.rtmsg_ifindex = 0;

 	    }
 	  else
 	    {
 	      if (nexthop->type == NEXTHOP_TYPE_IPV6
 		  || nexthop->type == NEXTHOP_TYPE_IPV6_IFNAME
 		  || nexthop->type == NEXTHOP_TYPE_IPV6_IFINDEX)
 		{
 		  memcpy (&rtm.rtmsg_gateway, &nexthop->gate.ipv6,
 			  sizeof (struct in6_addr));
 		}
 	      if (nexthop->type == NEXTHOP_TYPE_IFINDEX
 		  || nexthop->type == NEXTHOP_TYPE_IFNAME
 		  || nexthop->type == NEXTHOP_TYPE_IPV6_IFNAME
 		  || nexthop->type == NEXTHOP_TYPE_IPV6_IFINDEX)
 		rtm.rtmsg_ifindex = nexthop->ifindex;
 	      else
 		rtm.rtmsg_ifindex = 0;
 	    }

 	  if (cmd == SIOCADDRT)
 	    SET_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB);

 	  nexthop_num++;
 	  break;
 	}
     }

   /* If there is no useful nexthop then return. */
   if (nexthop_num == 0)
     {
       if (IS_ZEBRA_DEBUG_KERNEL)
 	zlog_debug ("netlink_route_multipath(): No useful nexthop.");
       return 0;
     }

   sock = socket (AF_INET6, SOCK_DGRAM, 0);
   if (sock < 0)
     {
       zlog_warn ("can't make socket\n");
       return -1;
     }

   /* Send message via ioctl. */
   ret = ioctl (sock, cmd, &rtm);
   if (ret < 0)
     {
       zlog_warn ("can't %s ipv6 route: %s\n",
 		 cmd == SIOCADDRT ? "add" : "delete",
 	   safe_strerror(errno));
       ret = errno;
       close (sock);
       return ret;
     }
   close (sock);

   return ret;
 }

 int
 kernel_add_ipv6 (struct prefix *p, struct rib *rib)
 {
   return kernel_ioctl_ipv6_multipath (SIOCADDRT, p, rib, AF_INET6);
 }

 int
 kernel_delete_ipv6 (struct prefix *p, struct rib *rib)
 {
   return kernel_ioctl_ipv6_multipath (SIOCDELRT, p, rib, AF_INET6);
 }

 /* Delete IPv6 route from the kernel. */
 int
 kernel_delete_ipv6_old (struct prefix_ipv6 *dest, struct in6_addr *gate,
 		    unsigned int index, int flags, int table)
 {
   return kernel_ioctl_ipv6 (SIOCDELRT, dest, gate, index, flags);
 }
 #endif /* HAVE_IPV6 */
	/*
	* kernel routing table update by ioctl().
	* Copyright (C) 1997, 98 Kunihiro Ishiguro
	*
	* This file is part of GNU Zebra.
	*
	* GNU Zebra is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License as published by the
	* Free Software Foundation; either version 2, or (at your option) any
	* later version.
	*
	* GNU Zebra is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with GNU Zebra; see the file COPYING. If not, write to the Free
	* Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
	* 02111-1307, USA.
	*/

	#include <zebra.h>

	#include "prefix.h"
	#include "log.h"
	#include "if.h"

	#include "zebra/zserv.h"
	#include "zebra/rib.h"
	#include "zebra/debug.h"
	#include "zebra/rt.h"

	/* Initialize of kernel interface. There is no kernel communication
	support under ioctl(). So this is dummy stub function. */
	void
	kernel_init (void)
	{
	return;
	}

	/* Dummy function of routing socket. */
	static void
	kernel_read (int sock)
	{
	return;
	}

	#if 0
	/* Initialization prototype of struct sockaddr_in. */
	static struct sockaddr_in sin_proto =
	{
	#ifdef HAVE_SIN_LEN
	sizeof (struct sockaddr_in),
	#endif /* HAVE_SIN_LEN */
	AF_INET, 0, {0}, {0}
	};
	#endif /* 0 */

	/* Solaris has ortentry. */
	#ifdef HAVE_OLD_RTENTRY
	#define rtentry ortentry
	#endif /* HAVE_OLD_RTENTRY */

	/* Interface to ioctl route message. */
	int
	kernel_add_route (struct prefix_ipv4 dest, struct in_addr gate,
	int index, int flags)
	{
	int ret;
	int sock;
	struct rtentry rtentry;
	struct sockaddr_in sin_dest, sin_mask, sin_gate;

	memset (&rtentry, 0, sizeof (struct rtentry));

	/* Make destination. */
	memset (&sin_dest, 0, sizeof (struct sockaddr_in));
	sin_dest.sin_family = AF_INET;
	#ifdef HAVE_SIN_LEN
	sin_dest.sin_len = sizeof (struct sockaddr_in);
	#endif /* HAVE_SIN_LEN */
	sin_dest.sin_addr = dest->prefix;

	/* Make gateway. */
	if (gate)
	{
	memset (&sin_gate, 0, sizeof (struct sockaddr_in));
	sin_gate.sin_family = AF_INET;
	#ifdef HAVE_SIN_LEN
	sin_gate.sin_len = sizeof (struct sockaddr_in);
	#endif /* HAVE_SIN_LEN */
	sin_gate.sin_addr = *gate;
	}

	memset (&sin_mask, 0, sizeof (struct sockaddr_in));
	sin_mask.sin_family = AF_INET;
	#ifdef HAVE_SIN_LEN
	sin_gate.sin_len = sizeof (struct sockaddr_in);
	#endif /* HAVE_SIN_LEN */
	masklen2ip (dest->prefixlen, &sin_mask.sin_addr);

	/* Set destination address, mask and gateway.*/
	memcpy (&rtentry.rt_dst, &sin_dest, sizeof (struct sockaddr_in));
	if (gate)
	memcpy (&rtentry.rt_gateway, &sin_gate, sizeof (struct sockaddr_in));
	#ifndef SUNOS_5
	memcpy (&rtentry.rt_genmask, &sin_mask, sizeof (struct sockaddr_in));
	#endif /* SUNOS_5 */

	/* Routing entry flag set. */
	if (dest->prefixlen == 32)
	rtentry.rt_flags \|= RTF_HOST;

	if (gate && gate->s_addr != INADDR_ANY)
	rtentry.rt_flags \|= RTF_GATEWAY;

	rtentry.rt_flags \|= RTF_UP;

	/* Additional flags */
	rtentry.rt_flags \|= flags;


	/* For tagging route. */
	/* rtentry.rt_flags \|= RTF_DYNAMIC; */

	/* Open socket for ioctl. */
	sock = socket (AF_INET, SOCK_DGRAM, 0);
	if (sock < 0)
	{
	zlog_warn ("can't make socket\n");
	return -1;
	}

	/* Send message by ioctl(). */
	ret = ioctl (sock, SIOCADDRT, &rtentry);
	if (ret < 0)
	{
	switch (errno)
	{
	case EEXIST:
	close (sock);
	return ZEBRA_ERR_RTEXIST;
	break;
	case ENETUNREACH:
	close (sock);
	return ZEBRA_ERR_RTUNREACH;
	break;
	case EPERM:
	close (sock);
	return ZEBRA_ERR_EPERM;
	break;
	}

	close (sock);
	zlog_warn ("write : %s (%d)", safe_strerror (errno), errno);
	return 1;
	}
	close (sock);

	return ret;
	}

	/* Interface to ioctl route message. */
	static int
	kernel_ioctl_ipv4 (u_long cmd, struct prefix p, struct rib rib, int family)
	{
	int ret;
	int sock;
	struct rtentry rtentry;
	struct sockaddr_in sin_dest, sin_mask, sin_gate;
	struct nexthop *nexthop;
	int nexthop_num = 0;
	struct interface *ifp;

	memset (&rtentry, 0, sizeof (struct rtentry));

	/* Make destination. */
	memset (&sin_dest, 0, sizeof (struct sockaddr_in));
	sin_dest.sin_family = AF_INET;
	#ifdef HAVE_SIN_LEN
	sin_dest.sin_len = sizeof (struct sockaddr_in);
	#endif /* HAVE_SIN_LEN */
	sin_dest.sin_addr = p->u.prefix4;

	if (CHECK_FLAG (rib->flags, ZEBRA_FLAG_BLACKHOLE))
	{
	SET_FLAG (rtentry.rt_flags, RTF_REJECT);

	if (cmd == SIOCADDRT)
	for (nexthop = rib->nexthop; nexthop; nexthop = nexthop->next)
	SET_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB);

	goto skip;
	}

	memset (&sin_gate, 0, sizeof (struct sockaddr_in));

	/* Make gateway. */
	for (nexthop = rib->nexthop; nexthop; nexthop = nexthop->next)
	{
	if ((cmd == SIOCADDRT
	&& CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_ACTIVE))
	\|\| (cmd == SIOCDELRT
	&& CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB)))
	{
	if (CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_RECURSIVE))
	{
	if (nexthop->rtype == NEXTHOP_TYPE_IPV4 \|\|
	nexthop->rtype == NEXTHOP_TYPE_IPV4_IFINDEX)
	{
	sin_gate.sin_family = AF_INET;
	#ifdef HAVE_SIN_LEN
	sin_gate.sin_len = sizeof (struct sockaddr_in);
	#endif /* HAVE_SIN_LEN */
	sin_gate.sin_addr = nexthop->rgate.ipv4;
	rtentry.rt_flags \|= RTF_GATEWAY;
	}
	if (nexthop->rtype == NEXTHOP_TYPE_IFINDEX
	\|\| nexthop->rtype == NEXTHOP_TYPE_IFNAME)
	{
	ifp = if_lookup_by_index (nexthop->rifindex);
	if (ifp)
	rtentry.rt_dev = ifp->name;
	else
	return -1;
	}
	}
	else
	{
	if (nexthop->type == NEXTHOP_TYPE_IPV4 \|\|
	nexthop->type == NEXTHOP_TYPE_IPV4_IFINDEX)
	{
	sin_gate.sin_family = AF_INET;
	#ifdef HAVE_SIN_LEN
	sin_gate.sin_len = sizeof (struct sockaddr_in);
	#endif /* HAVE_SIN_LEN */
	sin_gate.sin_addr = nexthop->gate.ipv4;
	rtentry.rt_flags \|= RTF_GATEWAY;
	}
	if (nexthop->type == NEXTHOP_TYPE_IFINDEX
	\|\| nexthop->type == NEXTHOP_TYPE_IFNAME)
	{
	ifp = if_lookup_by_index (nexthop->ifindex);
	if (ifp)
	rtentry.rt_dev = ifp->name;
	else
	return -1;
	}
	}

	if (cmd == SIOCADDRT)
	SET_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB);

	nexthop_num++;
	break;
	}
	}

	/* If there is no useful nexthop then return. */
	if (nexthop_num == 0)
	{
	if (IS_ZEBRA_DEBUG_KERNEL)
	zlog_debug ("netlink_route_multipath(): No useful nexthop.");
	return 0;
	}

	skip:

	memset (&sin_mask, 0, sizeof (struct sockaddr_in));
	sin_mask.sin_family = AF_INET;
	#ifdef HAVE_SIN_LEN
	sin_mask.sin_len = sizeof (struct sockaddr_in);
	#endif /* HAVE_SIN_LEN */
	masklen2ip (p->prefixlen, &sin_mask.sin_addr);

	/* Set destination address, mask and gateway.*/
	memcpy (&rtentry.rt_dst, &sin_dest, sizeof (struct sockaddr_in));

	if (rtentry.rt_flags & RTF_GATEWAY)
	memcpy (&rtentry.rt_gateway, &sin_gate, sizeof (struct sockaddr_in));

	#ifndef SUNOS_5
	memcpy (&rtentry.rt_genmask, &sin_mask, sizeof (struct sockaddr_in));
	#endif /* SUNOS_5 */

	/* Metric. It seems metric minus one value is installed... */
	rtentry.rt_metric = rib->metric;

	/* Routing entry flag set. */
	if (p->prefixlen == 32)
	rtentry.rt_flags \|= RTF_HOST;

	rtentry.rt_flags \|= RTF_UP;

	/* Additional flags */
	/* rtentry.rt_flags \|= flags; */

	/* For tagging route. */
	/* rtentry.rt_flags \|= RTF_DYNAMIC; */

	/* Open socket for ioctl. */
	sock = socket (AF_INET, SOCK_DGRAM, 0);
	if (sock < 0)
	{
	zlog_warn ("can't make socket\n");
	return -1;
	}

	/* Send message by ioctl(). */
	ret = ioctl (sock, cmd, &rtentry);
	if (ret < 0)
	{
	switch (errno)
	{
	case EEXIST:
	close (sock);
	return ZEBRA_ERR_RTEXIST;
	break;
	case ENETUNREACH:
	close (sock);
	return ZEBRA_ERR_RTUNREACH;
	break;
	case EPERM:
	close (sock);
	return ZEBRA_ERR_EPERM;
	break;
	}

	close (sock);
	zlog_warn ("write : %s (%d)", safe_strerror (errno), errno);
	return ret;
	}
	close (sock);

	return ret;
	}

	int
	kernel_add_ipv4 (struct prefix p, struct rib rib)
	{
	return kernel_ioctl_ipv4 (SIOCADDRT, p, rib, AF_INET);
	}

	int
	kernel_delete_ipv4 (struct prefix p, struct rib rib)
	{
	return kernel_ioctl_ipv4 (SIOCDELRT, p, rib, AF_INET);
	}

	#ifdef HAVE_IPV6

	/* Below is hack for GNU libc definition and Linux 2.1.X header. */
	#undef RTF_DEFAULT
	#undef RTF_ADDRCONF

	#include <asm/types.h>

	#if defined(__GLIBC__) && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 1
	/* struct in6_rtmsg will be declared in net/route.h. */
	#else
	#include <linux/ipv6_route.h>
	#endif

	static int
	kernel_ioctl_ipv6 (u_long type, struct prefix_ipv6 dest, struct in6_addr gate,
	int index, int flags)
	{
	int ret;
	int sock;
	struct in6_rtmsg rtm;

	memset (&rtm, 0, sizeof (struct in6_rtmsg));

	rtm.rtmsg_flags \|= RTF_UP;
	rtm.rtmsg_metric = 1;
	memcpy (&rtm.rtmsg_dst, &dest->prefix, sizeof (struct in6_addr));
	rtm.rtmsg_dst_len = dest->prefixlen;

	/* We need link local index. But this should be done caller...
	if (IN6_IS_ADDR_LINKLOCAL(&rtm.rtmsg_gateway))
	{
	index = if_index_address (&rtm.rtmsg_gateway);
	rtm.rtmsg_ifindex = index;
	}
	else
	rtm.rtmsg_ifindex = 0;
	*/

	rtm.rtmsg_flags \|= RTF_GATEWAY;

	/* For tagging route. */
	/* rtm.rtmsg_flags \|= RTF_DYNAMIC; */

	memcpy (&rtm.rtmsg_gateway, gate, sizeof (struct in6_addr));

	if (index)
	rtm.rtmsg_ifindex = index;
	else
	rtm.rtmsg_ifindex = 0;

	rtm.rtmsg_metric = 1;

	sock = socket (AF_INET6, SOCK_DGRAM, 0);
	if (sock < 0)
	{
	zlog_warn ("can't make socket\n");
	return -1;
	}

	/* Send message via ioctl. */
	ret = ioctl (sock, type, &rtm);
	if (ret < 0)
	{
	zlog_warn ("can't %s ipv6 route: %s\n", type == SIOCADDRT ? "add" : "delete",
	safe_strerror(errno));
	ret = errno;
	close (sock);
	return ret;
	}
	close (sock);

	return ret;
	}

	static int
	kernel_ioctl_ipv6_multipath (u_long cmd, struct prefix p, struct rib rib,
	int family)
	{
	int ret;
	int sock;
	struct in6_rtmsg rtm;
	struct nexthop *nexthop;
	int nexthop_num = 0;

	memset (&rtm, 0, sizeof (struct in6_rtmsg));

	rtm.rtmsg_flags \|= RTF_UP;
	rtm.rtmsg_metric = rib->metric;
	memcpy (&rtm.rtmsg_dst, &p->u.prefix, sizeof (struct in6_addr));
	rtm.rtmsg_dst_len = p->prefixlen;

	/* We need link local index. But this should be done caller...
	if (IN6_IS_ADDR_LINKLOCAL(&rtm.rtmsg_gateway))
	{
	index = if_index_address (&rtm.rtmsg_gateway);
	rtm.rtmsg_ifindex = index;
	}
	else
	rtm.rtmsg_ifindex = 0;
	*/

	rtm.rtmsg_flags \|= RTF_GATEWAY;

	/* For tagging route. */
	/* rtm.rtmsg_flags \|= RTF_DYNAMIC; */

	/* Make gateway. */
	for (nexthop = rib->nexthop; nexthop; nexthop = nexthop->next)
	{
	if ((cmd == SIOCADDRT
	&& CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_ACTIVE))
	\|\| (cmd == SIOCDELRT
	&& CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB)))
	{
	if (CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_RECURSIVE))
	{
	if (nexthop->rtype == NEXTHOP_TYPE_IPV6
	\|\| nexthop->rtype == NEXTHOP_TYPE_IPV6_IFNAME
	\|\| nexthop->rtype == NEXTHOP_TYPE_IPV6_IFINDEX)
	{
	memcpy (&rtm.rtmsg_gateway, &nexthop->rgate.ipv6,
	sizeof (struct in6_addr));
	}
	if (nexthop->rtype == NEXTHOP_TYPE_IFINDEX
	\|\| nexthop->rtype == NEXTHOP_TYPE_IFNAME
	\|\| nexthop->rtype == NEXTHOP_TYPE_IPV6_IFNAME
	\|\| nexthop->rtype == NEXTHOP_TYPE_IPV6_IFINDEX)
	rtm.rtmsg_ifindex = nexthop->rifindex;
	else
	rtm.rtmsg_ifindex = 0;

	}
	else
	{
	if (nexthop->type == NEXTHOP_TYPE_IPV6
	\|\| nexthop->type == NEXTHOP_TYPE_IPV6_IFNAME
	\|\| nexthop->type == NEXTHOP_TYPE_IPV6_IFINDEX)
	{
	memcpy (&rtm.rtmsg_gateway, &nexthop->gate.ipv6,
	sizeof (struct in6_addr));
	}
	if (nexthop->type == NEXTHOP_TYPE_IFINDEX
	\|\| nexthop->type == NEXTHOP_TYPE_IFNAME
	\|\| nexthop->type == NEXTHOP_TYPE_IPV6_IFNAME
	\|\| nexthop->type == NEXTHOP_TYPE_IPV6_IFINDEX)
	rtm.rtmsg_ifindex = nexthop->ifindex;
	else
	rtm.rtmsg_ifindex = 0;
	}

	if (cmd == SIOCADDRT)
	SET_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB);

	nexthop_num++;
	break;
	}
	}

	/* If there is no useful nexthop then return. */
	if (nexthop_num == 0)
	{
	if (IS_ZEBRA_DEBUG_KERNEL)
	zlog_debug ("netlink_route_multipath(): No useful nexthop.");
	return 0;
	}

	sock = socket (AF_INET6, SOCK_DGRAM, 0);
	if (sock < 0)
	{
	zlog_warn ("can't make socket\n");
	return -1;
	}

	/* Send message via ioctl. */
	ret = ioctl (sock, cmd, &rtm);
	if (ret < 0)
	{
	zlog_warn ("can't %s ipv6 route: %s\n",
	cmd == SIOCADDRT ? "add" : "delete",
	safe_strerror(errno));
	ret = errno;
	close (sock);
	return ret;
	}
	close (sock);

	return ret;
	}

	int
	kernel_add_ipv6 (struct prefix p, struct rib rib)
	{
	return kernel_ioctl_ipv6_multipath (SIOCADDRT, p, rib, AF_INET6);
	}

	int
	kernel_delete_ipv6 (struct prefix p, struct rib rib)
	{
	return kernel_ioctl_ipv6_multipath (SIOCDELRT, p, rib, AF_INET6);
	}

	/* Delete IPv6 route from the kernel. */
	int
	kernel_delete_ipv6_old (struct prefix_ipv6 dest, struct in6_addr gate,
	unsigned int index, int flags, int table)
	{
	return kernel_ioctl_ipv6 (SIOCDELRT, dest, gate, index, flags);
	}
	#endif /* HAVE_IPV6 */