bgpd: fix loc-rib open message should use router-id

When forging BMP open message, the BGP router-id of tx open message of
the BMP LOC-RIB peer up message is always set to 0.0.0.0, whatever the
configured value of 'bgp router-id'.

Actually, when forging a peer up LOC-RIB message, the BGP router-id
value should be taken from the main BGP instance, and not from the peer
bgp identifier. Fix this by refreshing the router-id whenever a peer up
loc-rib message should be sent.

Signed-off-by: Philippe Guibert <[email protected]>

bgpd/bgp_bmp.c

@@ -56,6 +56,7 @@ static int bmp_route_update_bgpbmp(struct bmp_targets *bt, afi_t afi, safi_t saf
 static void bmp_send_all_bgp(struct peer *peer, bool down);
 static struct bmp_imported_bgp *bmp_imported_bgp_find(struct bmp_targets *bt, char *name);
 static void bmp_stats_per_instance(struct bgp *bgp, struct bmp_targets *bt);
+static void bmp_bgp_peer_vrf(struct bmp_bgp_peer *bbpeer, struct bgp *bgp);
 
 DEFINE_MGROUP(BMP, "BMP (BGP Monitoring Protocol)");
 
@@ -551,9 +552,12 @@ static struct stream *bmp_peerstate(struct peer *peer, bool down)
 
 		bbpeer = bmp_bgp_peer_find(peer->qobj_node.nid);
 
-		if (bbpeer && bbpeer->open_tx)
+		if (bbpeer && bbpeer->open_tx) {
+			if (is_locrib)
+				/* update bgp id each time peer up LOC-RIB message is to be sent */
+				bmp_bgp_peer_vrf(bbpeer, peer->bgp);
 			stream_put(s, bbpeer->open_tx, bbpeer->open_tx_len);
-		else {
+		} else {
 			stream_put(s, dummy_open, sizeof(dummy_open));
 			zlog_warn("bmp: missing TX OPEN message for peer %s",
 				  peer->host);
@@ -2209,6 +2213,8 @@ static void bmp_bgp_peer_vrf(struct bmp_bgp_peer *bbpeer, struct bgp *bgp)
 	struct peer *peer = bgp->peer_self;
 	uint16_t send_holdtime;
 	as_t local_as;
+	struct stream *s;
+	size_t open_len;
 
 	if (CHECK_FLAG(peer->flags, PEER_FLAG_TIMER))
 		send_holdtime = peer->holdtime;
@@ -2221,15 +2227,19 @@ static void bmp_bgp_peer_vrf(struct bmp_bgp_peer *bbpeer, struct bgp *bgp)
 	else
 		local_as = peer->local_as;
 
-	struct stream *s = bgp_open_make(peer, send_holdtime, local_as);
-	size_t open_len = stream_get_endp(s);
+	s = bgp_open_make(peer, send_holdtime, local_as, &peer->local_id);
+	open_len = stream_get_endp(s);
 
 	bbpeer->open_rx_len = open_len;
 	if (bbpeer->open_rx)
 		XFREE(MTYPE_BMP_OPEN, bbpeer->open_rx);
 	bbpeer->open_rx = XMALLOC(MTYPE_BMP_OPEN, open_len);
 	memcpy(bbpeer->open_rx, s->data, open_len);
 
+	stream_free(s);
+
+	s = bgp_open_make(peer, send_holdtime, local_as, &bgp->router_id);
+	open_len = stream_get_endp(s);
 	bbpeer->open_tx_len = open_len;
 	if (bbpeer->open_tx)
 		XFREE(MTYPE_BMP_OPEN, bbpeer->open_tx);

bgpd/bgp_packet.c

@@ -637,7 +637,8 @@ void bgp_keepalive_send(struct peer *peer)
 	bgp_writes_on(peer->connection);
 }
 
-struct stream *bgp_open_make(struct peer *peer, uint16_t send_holdtime, as_t local_as)
+struct stream *bgp_open_make(struct peer *peer, uint16_t send_holdtime, as_t local_as,
+			     struct in_addr *id)
 {
 	struct stream *s = stream_new(BGP_STANDARD_MESSAGE_MAX_PACKET_SIZE);
 	bool ext_opt_params = false;
@@ -650,7 +651,7 @@ struct stream *bgp_open_make(struct peer *peer, uint16_t send_holdtime, as_t loc
 	stream_putw(s, (local_as <= BGP_AS_MAX) ? (uint16_t)local_as
 						: BGP_AS_TRANS);
 	stream_putw(s, send_holdtime);		/* Hold Time */
-	stream_put_in_addr(s, &peer->local_id); /* BGP Identifier */
+	stream_put_in_addr(s, id);		/* BGP Identifier */
 
 	/* Set capabilities */
 	if (CHECK_FLAG(peer->flags, PEER_FLAG_EXTENDED_OPT_PARAMS)) {
@@ -705,7 +706,7 @@ void bgp_open_send(struct peer_connection *connection)
 	else
 		local_as = peer->local_as;
 
-	s = bgp_open_make(peer, send_holdtime, local_as);
+	s = bgp_open_make(peer, send_holdtime, local_as, &peer->local_id);
 
 	/* Dump packet if debug option is set. */
 	/* bgp_packet_dump (s); */

bgpd/bgp_packet.h

@@ -49,7 +49,8 @@ DECLARE_HOOK(bgp_packet_send,
 
 /* Packet send and receive function prototypes. */
 extern void bgp_keepalive_send(struct peer *peer);
-extern struct stream *bgp_open_make(struct peer *peer, uint16_t send_holdtime, as_t local_as);
+extern struct stream *bgp_open_make(struct peer *peer, uint16_t send_holdtime, as_t local_as,
+				    struct in_addr *id);
 extern void bgp_open_send(struct peer_connection *connection);
 extern void bgp_notify_send(struct peer_connection *connection, uint8_t code,
 			    uint8_t sub_code);