static void
bgp_sock_err(sock *sk, int err)
{
struct bgp_conn *conn = sk->data;
struct bgp_proto *p = conn->bgp;
/*
* This error hook may be called either asynchronously from main
* loop, or synchronously from sk_send(). But sk_send() is called
* only from bgp_tx() and bgp_kick_tx(), which are both called
* asynchronously from main loop. Moreover, they end if err hook is
* called. Therefore, we could suppose that it is always called
* asynchronously.
*/
bgp_store_error(p, conn, BE_SOCKET, err);
if (err)
BGP_TRACE(D_EVENTS, "Connection lost (%M)", err);
else
BGP_TRACE(D_EVENTS, "Connection closed");
if ((conn->state == BS_ESTABLISHED) && p->gr_ready)
bgp_handle_graceful_restart(p);
bgp_conn_enter_idle_state(conn);
}
/**
* bgp_incoming_connection - handle an incoming connection
* @sk: TCP socket
* @dummy: unused
*
* This function serves as a socket hook for accepting of new BGP
* connections. It searches a BGP instance corresponding to the peer
* which has connected and if such an instance exists, it creates a
* &bgp_conn structure, attaches it to the instance and either sends
* an Open message or (if there already is an active connection) it
* closes the new connection by sending a Notification message.
*/
static int
bgp_incoming_connection(sock *sk, int dummy UNUSED)
{
struct proto_config *pc;
DBG("BGP: Incoming connection from %I port %d\n", sk->daddr, sk->dport);
WALK_LIST(pc, config->protos)
if (pc->protocol == &proto_bgp && pc->proto)
{
struct bgp_proto *p = (struct bgp_proto *) pc->proto;
if (ipa_equal(p->cf->remote_ip, sk->daddr) &&
(!ipa_has_link_scope(sk->daddr) || (p->cf->iface == sk->iface)))
{
/* We are in proper state and there is no other incoming connection */
int acc = (p->p.proto_state == PS_START || p->p.proto_state == PS_UP) &&
(p->start_state >= BSS_CONNECT) && (!p->incoming_conn.sk);
if (p->conn && (p->conn->state == BS_ESTABLISHED) && p->gr_ready)
{
bgp_store_error(p, NULL, BE_MISC, BEM_GRACEFUL_RESTART);
bgp_handle_graceful_restart(p);
bgp_conn_enter_idle_state(p->conn);
acc = 1;
}
BGP_TRACE(D_EVENTS, "Incoming connection from %I%J (port %d) %s",
sk->daddr, ipa_has_link_scope(sk->daddr) ? sk->iface : NULL,
sk->dport, acc ? "accepted" : "rejected");
if (!acc)
goto reject;
int hops = p->cf->multihop ? : 1;
if (sk_set_ttl(sk, p->cf->ttl_security ? 255 : hops) < 0)
goto err;
if (p->cf->ttl_security)
if (sk_set_min_ttl(sk, 256 - hops) < 0)
goto err;
bgp_setup_conn(p, &p->incoming_conn);
bgp_setup_sk(&p->incoming_conn, sk);
bgp_send_open(&p->incoming_conn);
return 0;
err:
sk_log_error(sk, p->p.name);
log(L_ERR "%s: Incoming connection aborted", p->p.name);
rfree(sk);
return 0;
}
}
int
bgp_apply_limits(struct bgp_proto *p)
{
if (p->cf->route_limit && (p->p.stats.imp_routes > p->cf->route_limit))
{
log(L_WARN "%s: Route limit exceeded, shutting down", p->p.name);
bgp_store_error(p, NULL, BE_AUTO_DOWN, BEA_ROUTE_LIMIT_EXCEEDED);
bgp_update_startup_delay(p);
bgp_stop(p, 1); // Errcode 6, 1 - max number of prefixes reached
return -1;
}
return 0;
}
/**
* bgp_open - open a BGP instance
* @p: BGP instance
*
* This function allocates and configures shared BGP resources.
* Should be called as the last step during initialization
* (when lock is acquired and neighbor is ready).
* When error, state changed to PS_DOWN, -1 is returned and caller
* should return immediately.
*/
static int
bgp_open(struct bgp_proto *p)
{
struct config *cfg = p->cf->c.global;
int errcode;
bgp_counter++;
if (!bgp_listen_sk)
bgp_listen_sk = bgp_setup_listen_sk(cfg->listen_bgp_addr, cfg->listen_bgp_port, cfg->listen_bgp_flags);
if (!bgp_listen_sk)
{
bgp_counter--;
errcode = BEM_NO_SOCKET;
goto err;
}
if (!bgp_linpool)
bgp_linpool = lp_new(&root_pool, 4080);
if (p->cf->password)
{
int rv = sk_set_md5_auth(bgp_listen_sk, p->cf->remote_ip, p->cf->iface, p->cf->password);
if (rv < 0)
{
bgp_close(p, 0);
errcode = BEM_INVALID_MD5;
goto err;
}
}
return 0;
err:
p->p.disabled = 1;
bgp_store_error(p, NULL, BE_MISC, errcode);
proto_notify_state(&p->p, PS_DOWN);
return -1;
}
/**
* bgp_incoming_connection - handle an incoming connection
* @sk: TCP socket
* @dummy: unused
*
* This function serves as a socket hook for accepting of new BGP
* connections. It searches a BGP instance corresponding to the peer
* which has connected and if such an instance exists, it creates a
* &bgp_conn structure, attaches it to the instance and either sends
* an Open message or (if there already is an active connection) it
* closes the new connection by sending a Notification message.
*/
static int
bgp_incoming_connection(sock *sk, int dummy UNUSED)
{
struct bgp_proto *p;
int acc, hops;
DBG("BGP: Incoming connection from %I port %d\n", sk->daddr, sk->dport);
p = bgp_find_proto(sk);
if (!p)
{
log(L_WARN "BGP: Unexpected connect from unknown address %I%J (port %d)",
sk->daddr, ipa_is_link_local(sk->daddr) ? sk->iface : NULL, sk->dport);
rfree(sk);
return 0;
}
/* We are in proper state and there is no other incoming connection */
acc = (p->p.proto_state == PS_START || p->p.proto_state == PS_UP) &&
(p->start_state >= BSS_CONNECT) && (!p->incoming_conn.sk);
if (p->conn && (p->conn->state == BS_ESTABLISHED) && p->gr_ready)
{
bgp_store_error(p, NULL, BE_MISC, BEM_GRACEFUL_RESTART);
bgp_handle_graceful_restart(p);
bgp_conn_enter_idle_state(p->conn);
acc = 1;
}
BGP_TRACE(D_EVENTS, "Incoming connection from %I%J (port %d) %s",
sk->daddr, ipa_is_link_local(sk->daddr) ? sk->iface : NULL,
sk->dport, acc ? "accepted" : "rejected");
if (!acc)
{
rfree(sk);
return 0;
}
hops = p->cf->multihop ? : 1;
if (sk_set_ttl(sk, p->cf->ttl_security ? 255 : hops) < 0)
goto err;
if (p->cf->ttl_security)
if (sk_set_min_ttl(sk, 256 - hops) < 0)
goto err;
if (p->cf->enable_extended_messages)
{
sk->rbsize = BGP_RX_BUFFER_EXT_SIZE;
sk->tbsize = BGP_TX_BUFFER_EXT_SIZE;
sk_reallocate(sk);
}
bgp_setup_conn(p, &p->incoming_conn);
bgp_setup_sk(&p->incoming_conn, sk);
bgp_send_open(&p->incoming_conn);
return 0;
err:
sk_log_error(sk, p->p.name);
log(L_ERR "%s: Incoming connection aborted", p->p.name);
rfree(sk);
return 0;
}
