bgpd: Prefer routes over eBGP versus eBGP-OAD

If at least one of the candidate routes was received via EBGP, remove from consideration all routes that were received via EBGP-OAD and IBGP. Signed-off-by: Donatas Abraitis <[email protected]>
FRRouting · Jan 11, 2024 · a8474e4 · a8474e4
1 parent 5fbf0cc
commit a8474e4
Showing 1 changed file with 20 additions and 10 deletions.
diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c
@@ -613,6 +613,8 @@ int bgp_path_info_cmp(struct bgp *bgp, struct bgp_path_info *new,
 	struct attr *newattr, *existattr;
 	enum bgp_peer_sort new_sort;
 	enum bgp_peer_sort exist_sort;
+	enum bgp_peer_sub_sort new_sub_sort;
+	enum bgp_peer_sub_sort exist_sub_sort;
 	uint32_t new_pref;
 	uint32_t exist_pref;
 	uint32_t new_med;
@@ -1147,26 +1149,34 @@ int bgp_path_info_cmp(struct bgp *bgp, struct bgp_path_info *new,
 	/* 7. Peer type check. */
 	new_sort = peer_new->sort;
 	exist_sort = peer_exist->sort;
+	new_sub_sort = peer_new->sub_sort;
+	exist_sub_sort = peer_exist->sub_sort;
 
-	if (new_sort == BGP_PEER_EBGP
-	    && (exist_sort == BGP_PEER_IBGP || exist_sort == BGP_PEER_CONFED)) {
+	if (new_sort == BGP_PEER_EBGP &&
+	    (exist_sort == BGP_PEER_IBGP || exist_sort == BGP_PEER_CONFED ||
+	     exist_sub_sort == BGP_PEER_EBGP_OAD)) {
 		*reason = bgp_path_selection_peer;
 		if (debug)
-			zlog_debug(
-				"%s: %s wins over %s due to eBGP peer > iBGP peer",
-				pfx_buf, new_buf, exist_buf);
+			zlog_debug("%s: %s wins over %s due to eBGP peer > %s peer",
+				   pfx_buf, new_buf, exist_buf,
+				   (exist_sub_sort == BGP_PEER_EBGP_OAD)
+					   ? "eBGP-OAD"
+					   : "iBGP");
 		if (!CHECK_FLAG(bgp->flags, BGP_FLAG_PEERTYPE_MULTIPATH_RELAX))
 			return 1;
 		peer_sort_ret = 1;
 	}
 
-	if (exist_sort == BGP_PEER_EBGP
-	    && (new_sort == BGP_PEER_IBGP || new_sort == BGP_PEER_CONFED)) {
+	if (exist_sort == BGP_PEER_EBGP &&
+	    (new_sort == BGP_PEER_IBGP || new_sort == BGP_PEER_CONFED ||
+	     new_sub_sort == BGP_PEER_EBGP_OAD)) {
 		*reason = bgp_path_selection_peer;
 		if (debug)
-			zlog_debug(
-				"%s: %s loses to %s due to iBGP peer < eBGP peer",
-				pfx_buf, new_buf, exist_buf);
+			zlog_debug("%s: %s loses to %s due to %s peer < eBGP peer",
+				   pfx_buf, new_buf, exist_buf,
+				   (exist_sub_sort == BGP_PEER_EBGP_OAD)
+					   ? "eBGP-OAD"
+					   : "iBGP");
 		if (!CHECK_FLAG(bgp->flags, BGP_FLAG_PEERTYPE_MULTIPATH_RELAX))
 			return 0;
 		peer_sort_ret = 0;