bgpd: sync seq numbers only if the MAC address is the same

We locate the sync path with the highest seq number for normalizing
local path to the same seq. With the change to maintain the VNI RT table
by IP address (instead of MAC&IP) we need additional changes to skip
paths with a different mac address than the local one we are trying to
normalize.

Signed-off-by: Anuradha Karuppiah <anuradhak@nvidia.com>

bgpd/bgp_evpn.c

@@ -1494,13 +1494,22 @@ static int update_evpn_type5_route(struct bgp *bgp_vrf, struct prefix_evpn *evp,
 static void bgp_evpn_get_sync_info(struct bgp *bgp, esi_t *esi,
 				   struct bgp_dest *dest, uint32_t loc_seq,
 				   uint32_t *max_sync_seq, bool *active_on_peer,
-				   bool *peer_router, bool *proxy_from_peer)
+				   bool *peer_router, bool *proxy_from_peer,
+				   const struct ethaddr *mac)
 {
 	struct bgp_path_info *tmp_pi;
 	struct bgp_path_info *second_best_path = NULL;
 	uint32_t tmp_mm_seq = 0;
 	esi_t *tmp_esi;
 	int paths_eq;
+	struct ethaddr *tmp_mac;
+	bool mac_cmp = false;
+	struct prefix_evpn *evp = (struct prefix_evpn *)&dest->p;
+
+
+	/* mac comparison is not needed for MAC-only routes */
+	if (mac && !is_evpn_prefix_ipaddr_none(evp))
+		mac_cmp = true;
 
 	/* find the best non-local path. a local path can only be present
 	 * as best path
@@ -1511,6 +1520,13 @@ static void bgp_evpn_get_sync_info(struct bgp *bgp, esi_t *esi,
 			!CHECK_FLAG(tmp_pi->flags, BGP_PATH_VALID))
 			continue;
 
+		/* ignore paths that have a different mac */
+		if (mac_cmp) {
+			tmp_mac = evpn_type2_path_info_get_mac(tmp_pi);
+			if (memcmp(mac, tmp_mac, sizeof(*mac)))
+				continue;
+		}
+
 		if (bgp_evpn_path_info_cmp(bgp, tmp_pi,
 				second_best_path, &paths_eq))
 			second_best_path = tmp_pi;
@@ -1555,7 +1571,8 @@ static void bgp_evpn_get_sync_info(struct bgp *bgp, esi_t *esi,
 static void update_evpn_route_entry_sync_info(struct bgp *bgp,
 					      struct bgp_dest *dest,
 					      struct attr *attr,
-					      uint32_t loc_seq, bool setup_sync)
+					      uint32_t loc_seq, bool setup_sync,
+					      const struct ethaddr *mac)
 {
 	esi_t *esi;
 	struct prefix_evpn *evp =
@@ -1574,7 +1591,8 @@ static void update_evpn_route_entry_sync_info(struct bgp *bgp,
 
 			bgp_evpn_get_sync_info(bgp, esi, dest, loc_seq,
 					       &max_sync_seq, &active_on_peer,
-					       &peer_router, &proxy_from_peer);
+					       &peer_router, &proxy_from_peer,
+					       mac);
 			attr->mm_sync_seqnum = max_sync_seq;
 			if (active_on_peer)
 				attr->es_flags |= ATTR_ES_PEER_ACTIVE;
@@ -1656,7 +1674,7 @@ static int update_evpn_route_entry(struct bgp *bgp, struct bgpevpn *vpn,
 	/* if a local path is being added with a non-zero esi look
 	 * for SYNC paths from ES peers and bubble up the sync-info
 	 */
-	update_evpn_route_entry_sync_info(bgp, dest, attr, seq, vpn_rt);
+	update_evpn_route_entry_sync_info(bgp, dest, attr, seq, vpn_rt, mac);
 
 	/* For non-GW MACs, update MAC mobility seq number, if needed. */
 	if (seq && !CHECK_FLAG(flags, ZEBRA_MACIP_TYPE_GW))