ospf6_asbr.c

linux 路由软件 可支持RIP OSPF BGP等

/*
 * Copyright (C) 2003 Yasuhiro Ohara
 *
 * 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 "log.h"
#include "memory.h"
#include "prefix.h"
#include "command.h"
#include "vty.h"
#include "routemap.h"
#include "table.h"
#include "plist.h"
#include "thread.h"
#include "linklist.h"

#include "ospf6_proto.h"
#include "ospf6_lsa.h"
#include "ospf6_lsdb.h"
#include "ospf6_route.h"
#include "ospf6_zebra.h"
#include "ospf6_message.h"

#include "ospf6_top.h"
#include "ospf6_area.h"
#include "ospf6_interface.h"
#include "ospf6_neighbor.h"
#include "ospf6_asbr.h"
#include "ospf6_intra.h"
#include "ospf6_flood.h"
#include "ospf6d.h"

unsigned char conf_debug_ospf6_asbr = 0;

char *zroute_name[] =
{ "system", "kernel", "connected", "static",
  "rip", "ripng", "ospf", "ospf6", "bgp", "unknown" };

char *zroute_abname[] =
{ "X", "K", "C", "S", "R", "R", "O", "O", "B", "?" };

#define ZROUTE_NAME(x)                                     \
  (0 < (x) && (x) < ZEBRA_ROUTE_MAX ? zroute_name[(x)] :   \
   zroute_name[ZEBRA_ROUTE_MAX])
#define ZROUTE_ABNAME(x)                                   \
  (0 < (x) && (x) < ZEBRA_ROUTE_MAX ? zroute_abname[(x)] : \
   zroute_abname[ZEBRA_ROUTE_MAX])

/* AS External LSA origination */
void
ospf6_as_external_lsa_originate (struct ospf6_route *route)
{
  char buffer[OSPF6_MAX_LSASIZE];
  struct ospf6_lsa_header *lsa_header;
  struct ospf6_lsa *old, *lsa;

  struct ospf6_as_external_lsa *as_external_lsa;
  char buf[64];
  caddr_t p;

  /* find previous LSA */
  old = ospf6_lsdb_lookup (htons (OSPF6_LSTYPE_AS_EXTERNAL),
                           route->path.origin.id, ospf6->router_id,
                           ospf6->lsdb);

  if (IS_OSPF6_DEBUG_ASBR || IS_OSPF6_DEBUG_ORIGINATE (AS_EXTERNAL))
    {
      prefix2str (&route->prefix, buf, sizeof (buf));
      zlog_info ("Originate AS-External-LSA for %s", buf);
    }

  /* prepare buffer */
  memset (buffer, 0, sizeof (buffer));
  lsa_header = (struct ospf6_lsa_header *) buffer;
  as_external_lsa = (struct ospf6_as_external_lsa *)
    ((caddr_t) lsa_header + sizeof (struct ospf6_lsa_header));
  p = (caddr_t)
    ((caddr_t) as_external_lsa + sizeof (struct ospf6_as_external_lsa));

  /* Fill AS-External-LSA */
  /* Metric type */
  if (route->path.metric_type == 2)
    SET_FLAG (as_external_lsa->bits_metric, OSPF6_ASBR_BIT_E);
  else
    UNSET_FLAG (as_external_lsa->bits_metric, OSPF6_ASBR_BIT_E);

  /* forwarding address */
  if (! IN6_IS_ADDR_UNSPECIFIED (&route->nexthop[0].address))
    SET_FLAG (as_external_lsa->bits_metric, OSPF6_ASBR_BIT_F);
  else
    UNSET_FLAG (as_external_lsa->bits_metric, OSPF6_ASBR_BIT_F);

  /* external route tag */
  UNSET_FLAG (as_external_lsa->bits_metric, OSPF6_ASBR_BIT_T);

  /* Set metric */
  OSPF6_ASBR_METRIC_SET (as_external_lsa, route->path.cost);

  /* prefixlen */
  as_external_lsa->prefix.prefix_length = route->prefix.prefixlen;

  /* PrefixOptions */
  as_external_lsa->prefix.prefix_options = route->path.prefix_options;

  /* don't use refer LS-type */
  as_external_lsa->prefix.prefix_refer_lstype = htons (0);

  /* set Prefix */
  memcpy (p, &route->prefix.u.prefix6,
          OSPF6_PREFIX_SPACE (route->prefix.prefixlen));
  ospf6_prefix_apply_mask (&as_external_lsa->prefix);
  p += OSPF6_PREFIX_SPACE (route->prefix.prefixlen);

  /* Forwarding address */
  if (CHECK_FLAG (as_external_lsa->bits_metric, OSPF6_ASBR_BIT_F))
    {
      memcpy (p, &route->nexthop[0].address, sizeof (struct in6_addr));
      p += sizeof (struct in6_addr);
    }

  /* External Route Tag */
  if (CHECK_FLAG (as_external_lsa->bits_metric, OSPF6_ASBR_BIT_T))
    {
      /* xxx */
    }

  /* Fill LSA Header */
  lsa_header->age = 0;
  lsa_header->type = htons (OSPF6_LSTYPE_AS_EXTERNAL);
  lsa_header->id = route->path.origin.id;
  lsa_header->adv_router = ospf6->router_id;
  lsa_header->seqnum =
    ospf6_new_ls_seqnum (lsa_header->type, lsa_header->id,
                         lsa_header->adv_router, ospf6->lsdb);
  lsa_header->length = htons ((caddr_t) p - (caddr_t) lsa_header);

  /* LSA checksum */
  ospf6_lsa_checksum (lsa_header);

  /* create LSA */
  lsa = ospf6_lsa_create (lsa_header);

  /* Originate */
  ospf6_lsa_originate_process (lsa, ospf6);
}


void
ospf6_asbr_lsa_add (struct ospf6_lsa *lsa)
{
  struct ospf6_as_external_lsa *external;
  struct prefix asbr_id;
  struct ospf6_route *asbr_entry, *route;
  char buf[64];
  int i;

  external = (struct ospf6_as_external_lsa *)
    OSPF6_LSA_HEADER_END (lsa->header);

  if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
    zlog_info ("Calculate AS-External route for %s", lsa->name);

  if (lsa->header->adv_router == ospf6->router_id)
    {
      if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
        zlog_info ("Ignore self-originated AS-External-LSA");
      return;
    }

  if (OSPF6_ASBR_METRIC (external) == LS_INFINITY)
    {
      if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
        zlog_info ("Ignore LSA with LSInfinity Metric");
      return;
    }

  ospf6_linkstate_prefix (lsa->header->adv_router, htonl (0), &asbr_id);
  asbr_entry = ospf6_route_lookup (&asbr_id, ospf6->brouter_table);
  if (asbr_entry == NULL ||
      ! CHECK_FLAG (asbr_entry->path.router_bits, OSPF6_ROUTER_BIT_E))
    {
      if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
        {
          prefix2str (&asbr_id, buf, sizeof (buf));
          zlog_info ("ASBR entry not found: %s", buf);
        }
      return;
    }

  route = ospf6_route_create ();
  route->type = OSPF6_DEST_TYPE_NETWORK;
  route->prefix.family = AF_INET6;
  route->prefix.prefixlen = external->prefix.prefix_length;
  ospf6_prefix_in6_addr (&route->prefix.u.prefix6, &external->prefix);

  route->path.area_id = asbr_entry->path.area_id;
  route->path.origin.type = lsa->header->type;
  route->path.origin.id = lsa->header->id;
  route->path.origin.adv_router = lsa->header->adv_router;

  route->path.prefix_options = external->prefix.prefix_options;
  if (CHECK_FLAG (external->bits_metric, OSPF6_ASBR_BIT_E))
    {
      route->path.type = OSPF6_PATH_TYPE_EXTERNAL2;
      route->path.metric_type = 2;
      route->path.cost = asbr_entry->path.cost;
      route->path.cost_e2 = OSPF6_ASBR_METRIC (external);
    }
  else
    {
      route->path.type = OSPF6_PATH_TYPE_EXTERNAL1;
      route->path.metric_type = 1;
      route->path.cost = asbr_entry->path.cost + OSPF6_ASBR_METRIC (external);
      route->path.cost_e2 = 0;
    }

  for (i = 0; i < OSPF6_MULTI_PATH_LIMIT; i++)
    ospf6_nexthop_copy (&route->nexthop[i], &asbr_entry->nexthop[i]);

  if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
    {
      prefix2str (&route->prefix, buf, sizeof (buf));
      zlog_info ("AS-External route add: %s", buf);
    }

  ospf6_route_add (route, ospf6->route_table);
}

void
ospf6_asbr_lsa_remove (struct ospf6_lsa *lsa)
{
  struct ospf6_as_external_lsa *external;
  struct prefix prefix;
  struct ospf6_route *route;
  char buf[64];

  external = (struct ospf6_as_external_lsa *)
    OSPF6_LSA_HEADER_END (lsa->header);

  if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
    zlog_info ("Withdraw AS-External route for %s", lsa->name);

  if (lsa->header->adv_router == ospf6->router_id)
    {
      if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
        zlog_info ("Ignore self-originated AS-External-LSA");
      return;
    }

  memset (&prefix, 0, sizeof (struct prefix));
  prefix.family = AF_INET6;
  prefix.prefixlen = external->prefix.prefix_length;
  ospf6_prefix_in6_addr (&prefix.u.prefix6, &external->prefix);

  route = ospf6_route_lookup (&prefix, ospf6->route_table);
  if (route == NULL)
    {
      if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
        {
          prefix2str (&prefix, buf, sizeof (buf));
          zlog_info ("AS-External route %s not found", buf);
        }
      return;
    }

  for (ospf6_route_lock (route);
       route && ospf6_route_is_prefix (&prefix, route);
       route = ospf6_route_next (route))
    {
      if (route->type != OSPF6_DEST_TYPE_NETWORK)
        continue;
      if (route->path.origin.type != lsa->header->type)
        continue;
      if (route->path.origin.id != lsa->header->id)
        continue;
      if (route->path.origin.adv_router != lsa->header->adv_router)
        continue;

      if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
        {
          prefix2str (&route->prefix, buf, sizeof (buf));
          zlog_info ("AS-External route remove: %s", buf);
        }
      ospf6_route_remove (route, ospf6->route_table);
    }
}

void
ospf6_asbr_lsentry_add (struct ospf6_route *asbr_entry)
{
  char buf[64];
  struct ospf6_lsa *lsa;
  u_int16_t type;
  u_int32_t router;

  if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
    {
      ospf6_linkstate_prefix2str (&asbr_entry->prefix, buf, sizeof (buf));
      zlog_info ("New ASBR %s found", buf);
    }

  type = htons (OSPF6_LSTYPE_AS_EXTERNAL);
  router = ospf6_linkstate_prefix_adv_router (&asbr_entry->prefix);
  for (lsa = ospf6_lsdb_type_router_head (type, router, ospf6->lsdb);
       lsa; lsa = ospf6_lsdb_type_router_next (type, router, lsa))
    {
      if (! OSPF6_LSA_IS_MAXAGE (lsa))
        ospf6_asbr_lsa_add (lsa);
    }

  if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
    {
      ospf6_linkstate_prefix2str (&asbr_entry->prefix, buf, sizeof (buf));
      zlog_info ("Calculation for new ASBR %s done", buf);
    }
}

void
ospf6_asbr_lsentry_remove (struct ospf6_route *asbr_entry)
{
  char buf[64];
  struct ospf6_lsa *lsa;
  u_int16_t type;
  u_int32_t router;

  if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
    {
      ospf6_linkstate_prefix2str (&asbr_entry->prefix, buf, sizeof (buf));
      zlog_info ("ASBR %s disappeared", buf);
    }

  type = htons (OSPF6_LSTYPE_AS_EXTERNAL);
  router = ospf6_linkstate_prefix_adv_router (&asbr_entry->prefix);
  for (lsa = ospf6_lsdb_type_router_head (type, router, ospf6->lsdb);
       lsa; lsa = ospf6_lsdb_type_router_next (type, router, lsa))
    ospf6_asbr_lsa_remove (lsa);

  if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
    {
      ospf6_linkstate_prefix2str (&asbr_entry->prefix, buf, sizeof (buf));
      zlog_info ("Calculation for old ASBR %s done", buf);
    }
}



/* redistribute function */

void
ospf6_asbr_routemap_set (int type, char *mapname)
{
  if (ospf6->rmap[type].name)
    free (ospf6->rmap[type].name);
  ospf6->rmap[type].name = strdup (mapname);
  ospf6->rmap[type].map = route_map_lookup_by_name (mapname);
}

void
ospf6_asbr_routemap_unset (int type)
{
  if (ospf6->rmap[type].name)
    free (ospf6->rmap[type].name);
  ospf6->rmap[type].name = NULL;
  ospf6->rmap[type].map = NULL;
}

void
ospf6_asbr_routemap_update (char *mapname)
{
  int type;

  if (ospf6 == NULL)
    return;

  for (type = 0; type < ZEBRA_ROUTE_MAX; type++)
    {
      if (ospf6->rmap[type].name)
        ospf6->rmap[type].map =
          route_map_lookup_by_name (ospf6->rmap[type].name);
      else
        ospf6->rmap[type].map = NULL;
    }
}

int
ospf6_asbr_is_asbr (struct ospf6 *o)
{
  return o->external_table->count;
}

void
ospf6_asbr_redistribute_set (int type)
{
  ospf6_zebra_redistribute (type);
}

void
ospf6_asbr_redistribute_unset (int type)
{
  struct ospf6_route *route;
  struct ospf6_external_info *info;

  ospf6_zebra_no_redistribute (type);

  for (route = ospf6_route_head (ospf6->external_table); route;
       route = ospf6_route_next (route))
    {
      info = route->route_option;
      if (info->type != type)
        continue;

      ospf6_asbr_redistribute_remove (info->type, route->nexthop[0].ifindex,
                                      &route->prefix);
    }
}