/* 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); }
/* 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; }
/* 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; }