bgpd.c

linux 路由软件 可支持RIP OSPF BGP等

}

/* Reset all address family specific configuration.  */
static void
peer_af_flag_reset (struct peer *peer, afi_t afi, safi_t safi)
{
  int i;
  struct bgp_filter *filter;
  char orf_name[BUFSIZ];

  filter = &peer->filter[afi][safi];

  /* Clear neighbor filter and route-map */
  for (i = FILTER_IN; i < FILTER_MAX; i++)
    {
      if (filter->dlist[i].name)
	{
	  free (filter->dlist[i].name);
	  filter->dlist[i].name = NULL;
	}
      if (filter->plist[i].name)
	{
	  free (filter->plist[i].name);
	  filter->plist[i].name = NULL; 
	}
      if (filter->aslist[i].name)
	{
	  free (filter->aslist[i].name);
	  filter->aslist[i].name = NULL;
	}
      if (filter->map[i].name)
	{
	  free (filter->map[i].name);
	  filter->map[i].name = NULL;
	}
    }

  /* Clear unsuppress map.  */
  if (filter->usmap.name)
    free (filter->usmap.name);
  filter->usmap.name = NULL;
  filter->usmap.map = NULL;

  /* Clear neighbor's all address family flags.  */
  peer->af_flags[afi][safi] = 0;

  /* Clear neighbor's all address family sflags. */
  peer->af_sflags[afi][safi] = 0;

  /* Clear neighbor's all address family capabilities. */
  peer->af_cap[afi][safi] = 0;

  /* Clear ORF info */
  peer->orf_plist[afi][safi] = NULL;
  sprintf (orf_name, "%s.%d.%d", peer->host, afi, safi);
  prefix_bgp_orf_remove_all (orf_name);

  /* Set default neighbor send-community.  */
  if (! bgp_option_check (BGP_OPT_CONFIG_CISCO))
    {
      SET_FLAG (peer->af_flags[afi][safi], PEER_FLAG_SEND_COMMUNITY);
      SET_FLAG (peer->af_flags[afi][safi], PEER_FLAG_SEND_EXT_COMMUNITY);
    }

  /* Clear neighbor default_originate_rmap */
  if (peer->default_rmap[afi][safi].name)
    free (peer->default_rmap[afi][safi].name);
  peer->default_rmap[afi][safi].name = NULL;
  peer->default_rmap[afi][safi].map = NULL;

  /* Clear neighbor maximum-prefix */
  peer->pmax[afi][safi] = 0;
  peer->pmax_threshold[afi][safi] = MAXIMUM_PREFIX_THRESHOLD_DEFAULT;

  /* Clear address family configuration */
  peer->af_config[afi][safi] = 0;
}

void 
peer_group_global_config_copy (struct peer *group, struct peer *peer)
{
  /* remote-as */
  if (group->as)
    peer->as = group->as;

  /* remote-as */
  if (group->change_local_as)
    peer->change_local_as = group->change_local_as;

  /* TTL */
  peer->ttl = group->ttl;

  peer->flags = group->flags;
  peer->config = group->config;

  /* peer timers apply */
  peer->holdtime = group->holdtime;
  peer->keepalive = group->keepalive;

  /* advertisement-interval reset */
  if (peer_sort (peer) == BGP_PEER_IBGP)
    peer->v_routeadv = BGP_DEFAULT_IBGP_ROUTEADV;
  else
    peer->v_routeadv = BGP_DEFAULT_EBGP_ROUTEADV;

#ifdef HAVE_TCP_SIGNATURE
  /* password apply */
  if (CHECK_FLAG (group->flags, PEER_FLAG_PASSWORD))
    {
      if (peer->password)
	free (peer->password);
      peer->password = strdup (group->password);

      bgp_tcpsig_set (bm->sock, peer);
    }
  else if (peer->password)
    {
      bgp_tcpsig_unset (bm->sock, peer);
      free (peer->password);
      peer->password = NULL;
    }
#endif /* HAVE_TCP_SIGNATURE */

  /* update-source apply */
  if (group->update_source)
    {
      if (peer->update_source)
	sockunion_free (peer->update_source);
      if (peer->update_if)
	{
	  XFREE (MTYPE_PEER_UPDATE_SOURCE, peer->update_if);
	  peer->update_if = NULL;
	}
      peer->update_source = sockunion_dup (group->update_source);
    }
  else if (group->update_if)
    {
      if (peer->update_if)
	XFREE (MTYPE_PEER_UPDATE_SOURCE, peer->update_if);
      if (peer->update_source)
	{
	  sockunion_free (peer->update_source);
	  peer->update_source = NULL;
	}
      peer->update_if = XSTRDUP (MTYPE_PEER_UPDATE_SOURCE, group->update_if);
    }
} 

void 
peer_group_af_config_copy (struct peer *group, struct peer *peer,
			   afi_t afi, safi_t safi)
{
  int in = FILTER_IN;
  int out = FILTER_OUT;
  struct bgp_filter *pfilter;
  struct bgp_filter *gfilter;

  pfilter = &peer->filter[afi][safi];
  gfilter = &group->filter[afi][safi];

  peer->af_flags[afi][safi] = group->af_flags[afi][safi];
  peer->af_config[afi][safi] = group->af_config[afi][safi];
  peer->weight[afi][safi] = group->weight[afi][safi];

  /* maximum-prefix */
  peer->pmax[afi][safi] = group->pmax[afi][safi];
  peer->pmax_threshold[afi][safi] = group->pmax_threshold[afi][safi];
  peer->pmax_restart[afi][safi] = group->pmax_restart[afi][safi];

  /* allowas-in */
  peer->allowas_in[afi][safi] = group->allowas_in[afi][safi];

  /* default-originate route-map */
  if (group->default_rmap[afi][safi].name)
    {
      if (peer->default_rmap[afi][safi].name)
	free (peer->default_rmap[afi][safi].name);
      peer->default_rmap[afi][safi].name = strdup (group->default_rmap[afi][safi].name);
      peer->default_rmap[afi][safi].map = group->default_rmap[afi][safi].map;
    }

  /* inbound filter apply */
  if (gfilter->dlist[in].name && ! pfilter->dlist[in].name)
    {
      if (pfilter->dlist[in].name)
	free (pfilter->dlist[in].name);
      pfilter->dlist[in].name = strdup (gfilter->dlist[in].name);
      pfilter->dlist[in].alist = gfilter->dlist[in].alist;
    }
  if (gfilter->plist[in].name && ! pfilter->plist[in].name)
    {
      if (pfilter->plist[in].name)
	free (pfilter->plist[in].name);
      pfilter->plist[in].name = strdup (gfilter->plist[in].name);
      pfilter->plist[in].plist = gfilter->plist[in].plist;
    }
  if (gfilter->aslist[in].name && ! pfilter->aslist[in].name)
    {
      if (pfilter->aslist[in].name)
	free (pfilter->aslist[in].name);
      pfilter->aslist[in].name = strdup (gfilter->aslist[in].name);
      pfilter->aslist[in].aslist = gfilter->aslist[in].aslist;
    }
  if (gfilter->map[in].name && ! pfilter->map[in].name)
    {
      if (pfilter->map[in].name)
	free (pfilter->map[in].name);
      pfilter->map[in].name = strdup (gfilter->map[in].name);
      pfilter->map[in].map = gfilter->map[in].map;
    }

  /* outbound filter apply */
  if (gfilter->dlist[out].name)
    {
      if (pfilter->dlist[out].name)
	free (pfilter->dlist[out].name);
      pfilter->dlist[out].name = strdup (gfilter->dlist[out].name);
      pfilter->dlist[out].alist = gfilter->dlist[out].alist;
    }
  else
    {
      if (pfilter->dlist[out].name)
	free (pfilter->dlist[out].name);
      pfilter->dlist[out].name = NULL;
      pfilter->dlist[out].alist = NULL;
    }
  if (gfilter->plist[out].name)
    {
      if (pfilter->plist[out].name)
	free (pfilter->plist[out].name);
      pfilter->plist[out].name = strdup (gfilter->plist[out].name);
      pfilter->plist[out].plist = gfilter->plist[out].plist;
    }
  else
    {
      if (pfilter->plist[out].name)
	free (pfilter->plist[out].name);
      pfilter->plist[out].name = NULL;
      pfilter->plist[out].plist = NULL;
    }
  if (gfilter->aslist[out].name)
    {
      if (pfilter->aslist[out].name)
	free (pfilter->aslist[out].name);
      pfilter->aslist[out].name = strdup (gfilter->aslist[out].name);
      pfilter->aslist[out].aslist = gfilter->aslist[out].aslist;
    }
  else
    {
      if (pfilter->aslist[out].name)
	free (pfilter->aslist[out].name);
      pfilter->aslist[out].name = NULL;
      pfilter->aslist[out].aslist = NULL;
    }
  if (gfilter->map[out].name)
    {
      if (pfilter->map[out].name)
	free (pfilter->map[out].name);
      pfilter->map[out].name = strdup (gfilter->map[out].name);
      pfilter->map[out].map = gfilter->map[out].map;
    }
  else
    {
      if (pfilter->map[out].name)
	free (pfilter->map[out].name);
      pfilter->map[out].name = NULL;
      pfilter->map[out].map = NULL;
    }

  if (gfilter->usmap.name)
    {
      if (pfilter->usmap.name)
	free (pfilter->usmap.name);
      pfilter->usmap.name = strdup (gfilter->usmap.name);
      pfilter->usmap.map = gfilter->usmap.map;
    }
  else
    {
      if (pfilter->usmap.name)
	free (pfilter->usmap.name);
      pfilter->usmap.name = NULL;
      pfilter->usmap.map = NULL;
    }
} 

/* Check peer's AS number and determin is this peer IBGP or EBGP */
int
peer_sort (struct peer *peer)
{
  struct bgp *bgp;

  bgp = peer->bgp;

  /* Peer-group */
  if (CHECK_FLAG (peer->sflags, PEER_STATUS_GROUP))
    {
      if (peer->as)
	return (bgp->as == peer->as ? BGP_PEER_IBGP : BGP_PEER_EBGP);
      else
	{
	  struct peer *peer1;
	  peer1 = listnode_head (peer->group->peer);
	  if (peer1)
	    return (peer1->local_as == peer1->as 
		    ? BGP_PEER_IBGP : BGP_PEER_EBGP);
	} 
      return BGP_PEER_INTERNAL;
    }

  /* Normal peer */
  if (bgp && CHECK_FLAG (bgp->config, BGP_CONFIG_CONFEDERATION))
    {
      if (peer->local_as == 0)
	return BGP_PEER_INTERNAL;

      if (peer->local_as == peer->as)
	{
	  if (peer->local_as == bgp->confed_id)
	    return BGP_PEER_EBGP;
	  else
	    return BGP_PEER_IBGP;
	}

      if (bgp_confederation_peers_check (bgp, peer->as))
	return BGP_PEER_CONFED;

      return BGP_PEER_EBGP;
    }
  else
    {
      return (peer->local_as == 0
	      ? BGP_PEER_INTERNAL : peer->local_as == peer->as
	      ? BGP_PEER_IBGP : BGP_PEER_EBGP);
    }
}

/* Allocate new peer object.  */
static struct peer *
peer_new ()
{
  afi_t afi;
  safi_t safi;
  struct peer *peer;
  struct servent *sp;

  /* Allocate new peer. */
  peer = XMALLOC (MTYPE_BGP_PEER, sizeof (struct peer));
  memset (peer, 0, sizeof (struct peer));

  /* Set default value. */
  peer->fd = -1;
  peer->v_start = BGP_INIT_START_TIMER;
  peer->v_connect = BGP_DEFAULT_CONNECT_RETRY;
  peer->v_asorig = BGP_DEFAULT_ASORIGINATE;
  peer->v_active_delay = BGP_ACTIVE_DELAY_TIMER;
  peer->status = Idle;
  peer->ostatus = Idle;
  peer->password = NULL;

  /* Set default flags.  */
  for (afi = AFI_IP; afi < AFI_MAX; afi++)
    for (safi = SAFI_UNICAST; safi < SAFI_MAX; safi++)
      {
	if (! bgp_option_check (BGP_OPT_CONFIG_CISCO))
	  {
	    SET_FLAG (peer->af_flags[afi][safi], PEER_FLAG_SEND_COMMUNITY);
	    SET_FLAG (peer->af_flags[afi][safi], PEER_FLAG_SEND_EXT_COMMUNITY);
	  }
	peer->orf_plist[afi][safi] = NULL;
      }
  SET_FLAG (peer->sflags, PEER_STATUS_CAPABILITY_OPEN);

  /* Create buffers.  */
  peer->ibuf = stream_new (BGP_MAX_PACKET_SIZE);
  peer->obuf = stream_fifo_new ();
  peer->work = stream_new (BGP_MAX_PACKET_SIZE);

  bgp_sync_init (peer);

  /* Get service port number.  */
  sp = getservbyname ("bgp", "tcp");
  peer->port = (sp == NULL) ? BGP_PORT_DEFAULT : ntohs (sp->s_port);

  return peer;
}

/* Create new BGP peer.  */
struct peer *
peer_create (union sockunion *su, struct bgp *bgp, as_t local_as,
	     as_t remote_as, afi_t afi, safi_t safi)
{
  int active;
  struct peer *peer;
  char buf[SU_ADDRSTRLEN];

  peer = peer_new ();
  peer->bgp = bgp;
  peer->su = *su;
  peer->local_as = local_as;
  peer->as = remote_as;
  peer->local_id = bgp->router_id;
  peer->v_holdtime = bgp->default_holdtime;
  peer->v_keepalive = bgp->default_keepalive;
  if (peer_sort (peer) == BGP_PEER_IBGP)
    peer->v_routeadv = BGP_DEFAULT_IBGP_ROUTEADV;
  else
    peer->v_routeadv = BGP_DEFAULT_EBGP_ROUTEADV;
  listnode_add_sort (bgp->peer, peer);

  active = peer_active (peer);

  if (afi && safi)
    peer->afc[afi][safi] = 1;

  /* Last read time set */
  peer->readtime = time (NULL);

  /* Last reset time set */
  peer->resettime = time (NULL);

  /* Default TTL set. */
  peer->ttl = (peer_sort (peer) == BGP_PEER_IBGP ? 255 : 1);

  /* Make peer's address string. */
  sockunion2str (su, buf, SU_ADDRSTRLEN);
  peer->host = strdup (buf);

  /* set peer first create flag */ 
  SET_FLAG (peer->sflags, PEER_STATUS_CREATE_INIT);

  /* Set up peer's events and timers. */
  if (! active && peer_active (peer))
    bgp_timer_set (peer);

  return peer;
}

/* Make accept BGP peer.  Called from bgp_accept (). */
struct peer *
peer_create_accept (struct bgp *bgp)
{
  struct peer *peer;

  peer = peer_new ();
  peer->bgp = bgp;
  listnode_add_sort (bgp->peer, peer);

  return peer;
}

/* Change peer's AS number.  */
void
peer_as_change (struct peer *peer, as_t as)
{
  int type;

  /* Stop peer. */
  if (! CHECK_FLAG (peer->sflags, PEER_STATUS_GROUP))
    {
      if (peer->status == Established)
	{
	  peer->last_reset = PEER_DOWN_REMOTE_AS_CHANGE;
	  bgp_notify_send (peer, BGP_NOTIFY_CEASE,
			   BGP_NOTIFY_CEASE_CONFIG_CHANGE);
	}
      else
	BGP_EVENT_ADD (peer, BGP_Stop);
    }
  type = peer_sort (peer);
  peer->as = as;

  if (bgp_config_check (peer->bgp, BGP_CONFIG_CONFEDERATION)
      && ! bgp_confederation_peers_check (peer->bgp, as)
      && peer->bgp->as != as)
    peer->local_as = peer->bgp->confed_id;
  else
    peer->local_as = peer->bgp->as;

  /* Advertisement-interval reset */
  if (peer_sort (peer) == BGP_PEER_IBGP)
    peer->v_routeadv = BGP_DEFAULT_IBGP_ROUTEADV;
  else
    peer->v_routeadv = BGP_DEFAULT_EBGP_ROUTEADV;

  /* TTL reset */
  if (peer_sort (peer) == BGP_PEER_IBGP)
    peer->ttl = 255;
  else if (type == BGP_PEER_IBGP)
    peer->ttl = 1;

  /* reflector-client reset */
  if (peer_sort (peer) != BGP_PEER_IBGP)
    {
      UNSET_FLAG (peer->af_flags[AFI_IP][SAFI_UNICAST],
		  PEER_FLAG_REFLECTOR_CLIENT);
      UNSET_FLAG (peer->af_flags[AFI_IP][SAFI_MULTICAST],
		  PEER_FLAG_REFLECTOR_CLIENT);
      UNSET_FLAG (peer->af_flags[AFI_IP][SAFI_MPLS_VPN],
		  PEER_FLAG_REFLECTOR_CLIENT);
      UNSET_FLAG (peer->af_flags[AFI_IP6][SAFI_UNICAST],
		  PEER_FLAG_REFLECTOR_CLIENT);
      UNSET_FLAG (peer->af_flags[AFI_IP6][SAFI_MULTICAST],
		  PEER_FLAG_REFLECTOR_CLIENT);
    }

  /* local-as reset */
  if (peer_sort (peer) != BGP_PEER_EBGP)
    {
      peer->change_local_as = 0;
      UNSET_FLAG (peer->flags, PEER_FLAG_LOCAL_AS_NO_PREPEND);
    }
}

/* If peer does not exist, create new one.  If peer already exists,
   set AS number to the peer.  */
int
peer_remote_as (struct bgp *bgp, union sockunion *su, as_t *as,
		afi_t afi, safi_t safi)
{
  struct peer *peer;
  as_t local_as;

  peer = peer_lookup (bgp, su);

  if (peer)
    {
      /* When this peer is a member of peer-group.  */
      if (peer->group)
	{
	  if (peer->group->conf->as)
	    {
	      /* Return peer group's AS number.  */
	      *as = peer->group->conf->as;
	      return BGP_ERR_PEER_GROUP_MEMBER;
	    }
	  if (peer_sort (peer->group->conf) == BGP_PEER_IBGP)
	    {
	      if (bgp->as != *as)
		{
		  *as = peer->as;
		  return BGP_ERR_PEER_GROUP_PEER_TYPE_DIFFERENT;
		}
	    }
	  else
	    {