From: Donatas Abraitis <donatas@opensourcerouting.org>
Date: Tue, 12 Nov 2024 11:09:09 +0000 (+0200)
Subject: bgpd: Update source address for BFD session
X-Git-Tag: docker/10.1.3~17^2~3
X-Git-Url: https://git.puffer.fish/?a=commitdiff_plain;h=a681fa69b893d38cf8a2e28d7fc4f1b7c1ba442d;p=matthieu%2Ffrr.git

bgpd: Update source address for BFD session

If BFD is down, we should try to detect the source automatically from the given
interface.

Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>
---

diff --git a/bgpd/bgp_bfd.c b/bgpd/bgp_bfd.c
index af6068cb1f..1fad9f1c0f 100644
--- a/bgpd/bgp_bfd.c
+++ b/bgpd/bgp_bfd.c
@@ -26,6 +26,7 @@
 #include "bgpd/bgp_debug.h"
 #include "bgpd/bgp_vty.h"
 #include "bgpd/bgp_packet.h"
+#include "bgpd/bgp_network.h"
 
 DEFINE_MTYPE_STATIC(BGPD, BFD_CONFIG, "BFD configuration data");
 
@@ -158,16 +159,33 @@ void bgp_peer_bfd_update_source(struct peer *p)
 		struct in_addr v4;
 		struct in6_addr v6;
 	} src, dst;
+	struct interface *ifp;
+	union sockunion addr;
 
 	/* Nothing to do for groups. */
 	if (CHECK_FLAG(p->sflags, PEER_STATUS_GROUP))
 		return;
 
 	/* Figure out the correct source to use. */
-	if (CHECK_FLAG(p->flags, PEER_FLAG_UPDATE_SOURCE) && p->update_source)
-		source = p->update_source;
-	else
+	if (CHECK_FLAG(p->flags, PEER_FLAG_UPDATE_SOURCE)) {
+		if (p->update_source) {
+			source = p->update_source;
+		} else if (p->update_if) {
+			ifp = if_lookup_by_name(p->update_if, p->bgp->vrf_id);
+			if (ifp) {
+				sockunion_init(&addr);
+				if (bgp_update_address(ifp, &p->connection->su, &addr)) {
+					if (BGP_DEBUG(bfd, BFD_LIB))
+						zlog_debug("%s: can't find the source address for interface %s",
+							   __func__, p->update_if);
+				}
+
+				source = &addr;
+			}
+		}
+	} else {
 		source = p->su_local;
+	}
 
 	/* Update peer's source/destination addresses. */
 	bfd_sess_addresses(session, &family, &src.v6, &dst.v6);