/* BGP try to connect to the peer.  */
int
bgp_connect (struct peer *peer)
{
  unsigned int ifindex = 0;

  /* Make socket for the peer. */
  peer->fd = sockunion_socket (&peer->su);
  if (peer->fd < 0)
    return -1;

  set_nonblocking (peer->fd);

  /* Set socket send buffer size */
  bgp_update_sock_send_buffer_size(peer->fd);

  bgp_set_socket_ttl (peer, peer->fd);

  sockopt_reuseaddr (peer->fd);
  sockopt_reuseport (peer->fd);
  
#ifdef IPTOS_PREC_INTERNETCONTROL
  if (bgpd_privs.change (ZPRIVS_RAISE))
    zlog_err ("%s: could not raise privs", __func__);
  if (sockunion_family (&peer->su) == AF_INET)
    setsockopt_ipv4_tos (peer->fd, IPTOS_PREC_INTERNETCONTROL);
# ifdef HAVE_IPV6
  else if (sockunion_family (&peer->su) == AF_INET6)
    setsockopt_ipv6_tclass (peer->fd, IPTOS_PREC_INTERNETCONTROL);
# endif
  if (bgpd_privs.change (ZPRIVS_LOWER))
    zlog_err ("%s: could not lower privs", __func__);
#endif

  if (peer->password)
    bgp_md5_set_connect (peer->fd, &peer->su, peer->password);

  /* Bind socket. */
  bgp_bind (peer);

  /* Update source bind. */
  bgp_update_source (peer);

#ifdef HAVE_IPV6
  if (peer->ifname)
    ifindex = if_nametoindex (peer->ifname);
#endif /* HAVE_IPV6 */

  if (BGP_DEBUG (events, EVENTS))
    plog_debug (peer->log, "%s [Event] Connect start to %s fd %d",
	       peer->host, peer->host, peer->fd);

  /* Connect to the remote peer. */
  return sockunion_connect (peer->fd, &peer->su, htons (peer->port), ifindex);
}
Пример #2
0
/* BGP try to connect to the peer.  */
int bgp_connect(struct peer *peer)
{
	assert(!CHECK_FLAG(peer->thread_flags, PEER_THREAD_WRITES_ON));
	assert(!CHECK_FLAG(peer->thread_flags, PEER_THREAD_READS_ON));
	ifindex_t ifindex = 0;

	if (peer->conf_if && BGP_PEER_SU_UNSPEC(peer)) {
		zlog_debug("Peer address not learnt: Returning from connect");
		return 0;
	}
	frr_elevate_privs(&bgpd_privs) {
	/* Make socket for the peer. */
		peer->fd = vrf_sockunion_socket(&peer->su, peer->bgp->vrf_id,
						bgp_get_bound_name(peer));
	}
	if (peer->fd < 0)
		return -1;

	set_nonblocking(peer->fd);

	/* Set socket send buffer size */
	setsockopt_so_sendbuf(peer->fd, BGP_SOCKET_SNDBUF_SIZE);

	if (bgp_set_socket_ttl(peer, peer->fd) < 0)
		return -1;

	sockopt_reuseaddr(peer->fd);
	sockopt_reuseport(peer->fd);

#ifdef IPTOS_PREC_INTERNETCONTROL
	frr_elevate_privs(&bgpd_privs) {
		if (sockunion_family(&peer->su) == AF_INET)
			setsockopt_ipv4_tos(peer->fd,
					    IPTOS_PREC_INTERNETCONTROL);
		else if (sockunion_family(&peer->su) == AF_INET6)
			setsockopt_ipv6_tclass(peer->fd,
					       IPTOS_PREC_INTERNETCONTROL);
	}
#endif

	if (peer->password) {
		uint16_t prefixlen = peer->su.sa.sa_family == AF_INET
					     ? IPV4_MAX_PREFIXLEN
					     : IPV6_MAX_PREFIXLEN;

		bgp_md5_set_connect(peer->fd, &peer->su, prefixlen,
				    peer->password);
	}

	/* Update source bind. */
	if (bgp_update_source(peer) < 0) {
		return connect_error;
	}

	if (peer->conf_if || peer->ifname)
		ifindex = ifname2ifindex(peer->conf_if ? peer->conf_if
						       : peer->ifname,
					 peer->bgp->vrf_id);

	if (bgp_debug_neighbor_events(peer))
		zlog_debug("%s [Event] Connect start to %s fd %d", peer->host,
			   peer->host, peer->fd);

	/* Connect to the remote peer. */
	return sockunion_connect(peer->fd, &peer->su, htons(peer->port),
				 ifindex);
}
/* Accept bgp connection. */
static int
bgp_accept (struct thread *thread)
{
  int bgp_sock;
  int accept_sock;
  union sockunion su;
  struct bgp_listener *listener = THREAD_ARG(thread);
  struct peer *peer;
  struct peer *peer1;
  char buf[SU_ADDRSTRLEN];

  /* Register accept thread. */
  accept_sock = THREAD_FD (thread);
  if (accept_sock < 0)
    {
      zlog_err ("accept_sock is nevative value %d", accept_sock);
      return -1;
    }
  listener->thread = thread_add_read (master, bgp_accept, listener, accept_sock);

  /* Accept client connection. */
  bgp_sock = sockunion_accept (accept_sock, &su);
  if (bgp_sock < 0)
    {
      zlog_err ("[Error] BGP socket accept failed (%s)", safe_strerror (errno));
      return -1;
    }
  set_nonblocking (bgp_sock);

  /* Set socket send buffer size */
  bgp_update_sock_send_buffer_size(bgp_sock);

  if (BGP_DEBUG (events, EVENTS))
    zlog_debug ("[Event] BGP connection from host %s", inet_sutop (&su, buf));
  
  /* Check remote IP address */
  peer1 = peer_lookup (NULL, &su);
  if (! peer1 || peer1->status == Idle)
    {
      if (BGP_DEBUG (events, EVENTS))
	{
	  if (! peer1)
	    zlog_debug ("[Event] BGP connection IP address %s is not configured",
		       inet_sutop (&su, buf));
	  else
	    zlog_debug ("[Event] BGP connection IP address %s is Idle state",
		       inet_sutop (&su, buf));
	}
      close (bgp_sock);
      return -1;
    }

  bgp_set_socket_ttl (peer1, bgp_sock);

  /* Make dummy peer until read Open packet. */
  if (BGP_DEBUG (events, EVENTS))
    zlog_debug ("[Event] Make dummy peer structure until read Open packet");

  {
    char buf[SU_ADDRSTRLEN];

    peer = peer_create_accept (peer1->bgp);
    SET_FLAG (peer->sflags, PEER_STATUS_ACCEPT_PEER);
    peer->su = su;
    peer->fd = bgp_sock;
    peer->status = Active;
    peer->local_id = peer1->local_id;
    peer->v_holdtime = peer1->v_holdtime;
    peer->v_keepalive = peer1->v_keepalive;

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

  BGP_EVENT_ADD (peer, TCP_connection_open);

  return 0;
}
Пример #4
0
/* Accept bgp connection. */
static int bgp_accept(struct thread *thread)
{
	int bgp_sock;
	int accept_sock;
	union sockunion su;
	struct bgp_listener *listener = THREAD_ARG(thread);
	struct peer *peer;
	struct peer *peer1;
	char buf[SU_ADDRSTRLEN];
	struct bgp *bgp = NULL;

	sockunion_init(&su);

	/* Register accept thread. */
	accept_sock = THREAD_FD(thread);
	if (accept_sock < 0) {
		flog_err_sys(EC_LIB_SOCKET, "accept_sock is nevative value %d",
			     accept_sock);
		return -1;
	}
	listener->thread = NULL;

	thread_add_read(bm->master, bgp_accept, listener, accept_sock,
			&listener->thread);

	/* Accept client connection. */
	bgp_sock = sockunion_accept(accept_sock, &su);
	if (bgp_sock < 0) {
		flog_err_sys(EC_LIB_SOCKET,
			     "[Error] BGP socket accept failed (%s)",
			     safe_strerror(errno));
		return -1;
	}
	set_nonblocking(bgp_sock);

	/* Obtain BGP instance this connection is meant for.
	 * - if it is a VRF netns sock, then BGP is in listener structure
	 * - otherwise, the bgp instance need to be demultiplexed
	 */
	if (listener->bgp)
		bgp = listener->bgp;
	else if (bgp_get_instance_for_inc_conn(bgp_sock, &bgp)) {
		if (bgp_debug_neighbor_events(NULL))
			zlog_debug(
				"[Event] Could not get instance for incoming conn from %s",
				inet_sutop(&su, buf));
		close(bgp_sock);
		return -1;
	}

	/* Set socket send buffer size */
	setsockopt_so_sendbuf(bgp_sock, BGP_SOCKET_SNDBUF_SIZE);

	/* Check remote IP address */
	peer1 = peer_lookup(bgp, &su);

	if (!peer1) {
		peer1 = peer_lookup_dynamic_neighbor(bgp, &su);
		if (peer1) {
			/* Dynamic neighbor has been created, let it proceed */
			peer1->fd = bgp_sock;
			bgp_fsm_change_status(peer1, Active);
			BGP_TIMER_OFF(
				peer1->t_start); /* created in peer_create() */

			if (peer_active(peer1))
				BGP_EVENT_ADD(peer1, TCP_connection_open);

			return 0;
		}
	}

	if (!peer1) {
		if (bgp_debug_neighbor_events(NULL)) {
			zlog_debug(
				"[Event] %s connection rejected - not configured"
				" and not valid for dynamic",
				inet_sutop(&su, buf));
		}
		close(bgp_sock);
		return -1;
	}

	if (CHECK_FLAG(peer1->flags, PEER_FLAG_SHUTDOWN)) {
		if (bgp_debug_neighbor_events(peer1))
			zlog_debug(
				"[Event] connection from %s rejected due to admin shutdown",
				inet_sutop(&su, buf));
		close(bgp_sock);
		return -1;
	}

	/*
	 * Do not accept incoming connections in Clearing state. This can result
	 * in incorect state transitions - e.g., the connection goes back to
	 * Established and then the Clearing_Completed event is generated. Also,
	 * block incoming connection in Deleted state.
	 */
	if (peer1->status == Clearing || peer1->status == Deleted) {
		if (bgp_debug_neighbor_events(peer1))
			zlog_debug(
				"[Event] Closing incoming conn for %s (%p) state %d",
				peer1->host, peer1, peer1->status);
		close(bgp_sock);
		return -1;
	}

	/* Check that at least one AF is activated for the peer. */
	if (!peer_active(peer1)) {
		if (bgp_debug_neighbor_events(peer1))
			zlog_debug(
				"%s - incoming conn rejected - no AF activated for peer",
				peer1->host);
		close(bgp_sock);
		return -1;
	}

	if (bgp_debug_neighbor_events(peer1))
		zlog_debug("[Event] BGP connection from host %s fd %d",
			   inet_sutop(&su, buf), bgp_sock);

	if (peer1->doppelganger) {
		/* We have an existing connection. Kill the existing one and run
		   with this one.
		*/
		if (bgp_debug_neighbor_events(peer1))
			zlog_debug(
				"[Event] New active connection from peer %s, Killing"
				" previous active connection",
				peer1->host);
		peer_delete(peer1->doppelganger);
	}

	if (bgp_set_socket_ttl(peer1, bgp_sock) < 0)
		if (bgp_debug_neighbor_events(peer1))
			zlog_debug(
				"[Event] Unable to set min/max TTL on peer %s, Continuing",
				peer1->host);

	peer = peer_create(&su, peer1->conf_if, peer1->bgp, peer1->local_as,
			   peer1->as, peer1->as_type, 0, 0, NULL);
	hash_release(peer->bgp->peerhash, peer);
	hash_get(peer->bgp->peerhash, peer, hash_alloc_intern);

	peer_xfer_config(peer, peer1);
	UNSET_FLAG(peer->flags, PEER_FLAG_CONFIG_NODE);

	peer->doppelganger = peer1;
	peer1->doppelganger = peer;
	peer->fd = bgp_sock;
	vrf_bind(peer->bgp->vrf_id, bgp_sock, bgp_get_bound_name(peer));
	bgp_fsm_change_status(peer, Active);
	BGP_TIMER_OFF(peer->t_start); /* created in peer_create() */

	SET_FLAG(peer->sflags, PEER_STATUS_ACCEPT_PEER);

	/* Make dummy peer until read Open packet. */
	if (peer1->status == Established
	    && CHECK_FLAG(peer1->sflags, PEER_STATUS_NSF_MODE)) {
		/* If we have an existing established connection with graceful
		 * restart
		 * capability announced with one or more address families, then
		 * drop
		 * existing established connection and move state to connect.
		 */
		peer1->last_reset = PEER_DOWN_NSF_CLOSE_SESSION;
		SET_FLAG(peer1->sflags, PEER_STATUS_NSF_WAIT);
		bgp_event_update(peer1, TCP_connection_closed);
	}

	if (peer_active(peer)) {
		BGP_EVENT_ADD(peer, TCP_connection_open);
	}

	return 0;
}