bgpd: Fix no form for neighbor X capability software-version

If `bgp default software-version-capability` is enabled, allow unsetting this for a single neighbor also. Signed-off-by: Donatas Abraitis <[email protected]>
FRRouting · Mar 9, 2024 · 70b4f5b · 70b4f5b
1 parent aa6ceee
commit 70b4f5b
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Showing 4 changed files with 55 additions and 30 deletions.
diff --git a/bgpd/bgp_open.c b/bgpd/bgp_open.c
@@ -2039,7 +2039,6 @@ uint16_t bgp_open_capability(struct stream *s, struct peer *peer,
 	 * or disable its use, and that switch MUST be off by default.
 	 */
 	if (peergroup_flag_check(peer, PEER_FLAG_CAPABILITY_SOFT_VERSION) ||
-	    CHECK_FLAG(peer->bgp->flags, BGP_FLAG_SOFT_VERSION_CAPABILITY) ||
 	    peer->sort == BGP_PEER_IBGP || peer->sub_sort == BGP_PEER_EBGP_OAD) {
 		SET_FLAG(peer->cap, PEER_CAP_SOFT_VERSION_ADV);
 		stream_putc(s, BGP_OPEN_OPT_CAP);

diff --git a/bgpd/bgp_packet.c b/bgpd/bgp_packet.c
@@ -1240,37 +1240,50 @@ void bgp_capability_send(struct peer *peer, afi_t afi, safi_t safi,
 	/* Encode MP_EXT capability. */
 	switch (capability_code) {
 	case CAPABILITY_CODE_SOFT_VERSION:
-		SET_FLAG(peer->cap, PEER_CAP_SOFT_VERSION_ADV);
-		stream_putc(s, action);
-		stream_putc(s, CAPABILITY_CODE_SOFT_VERSION);
-		cap_len = stream_get_endp(s);
-		stream_putc(s, 0); /* Capability Length */
-
-		/* The Capability Length SHOULD be no greater than 64.
-		 * This is the limit to allow other capabilities as much
-		 * space as they require.
+		/* Software Version capability
+		 * An implementation is REQUIRED Extended Optional Parameters
+		 * Length for BGP OPEN Message support as defined in [RFC9072].
+		 * The inclusion of the Software Version Capability is OPTIONAL.
+		 * If an implementation supports the inclusion of the capability,
+		 * the implementation MUST include a configuration switch to enable
+		 * or disable its use, and that switch MUST be off by default.
 		 */
-		const char *soft_version = cmd_software_version_get();
+		if (peergroup_flag_check(peer,
+					 PEER_FLAG_CAPABILITY_SOFT_VERSION) ||
+		    peer->sort == BGP_PEER_IBGP ||
+		    peer->sub_sort == BGP_PEER_EBGP_OAD) {
+			SET_FLAG(peer->cap, PEER_CAP_SOFT_VERSION_ADV);
+			stream_putc(s, action);
+			stream_putc(s, CAPABILITY_CODE_SOFT_VERSION);
+			cap_len = stream_get_endp(s);
+			stream_putc(s, 0); /* Capability Length */
 
-		len = strlen(soft_version);
-		if (len > BGP_MAX_SOFT_VERSION)
-			len = BGP_MAX_SOFT_VERSION;
+			/* The Capability Length SHOULD be no greater than 64.
+			* This is the limit to allow other capabilities as much
+			* space as they require.
+			*/
+			const char *soft_version = cmd_software_version_get();
 
-		stream_putc(s, len);
-		stream_put(s, soft_version, len);
+			len = strlen(soft_version);
+			if (len > BGP_MAX_SOFT_VERSION)
+				len = BGP_MAX_SOFT_VERSION;
 
-		/* Software Version capability Len. */
-		len = stream_get_endp(s) - cap_len - 1;
-		stream_putc_at(s, cap_len, len);
+			stream_putc(s, len);
+			stream_put(s, soft_version, len);
 
-		if (bgp_debug_neighbor_events(peer))
-			zlog_debug("%pBP sending CAPABILITY has %s %s for afi/safi: %s/%s",
-				   peer,
-				   action == CAPABILITY_ACTION_SET
-					   ? "Advertising"
-					   : "Removing",
-				   capability, iana_afi2str(pkt_afi),
-				   iana_safi2str(pkt_safi));
+			/* Software Version capability Len. */
+			len = stream_get_endp(s) - cap_len - 1;
+			stream_putc_at(s, cap_len, len);
+
+			if (bgp_debug_neighbor_events(peer))
+				zlog_debug("%pBP sending CAPABILITY has %s %s for afi/safi: %s/%s",
+					   peer,
+					   action == CAPABILITY_ACTION_SET
+						   ? "Advertising"
+						   : "Removing",
+					   capability, iana_afi2str(pkt_afi),
+					   iana_safi2str(pkt_safi));
+		}
 		break;
 	case CAPABILITY_CODE_MP:
 		stream_putc(s, action);

diff --git a/bgpd/bgp_vty.c b/bgpd/bgp_vty.c
@@ -18416,9 +18416,19 @@ static void bgp_config_write_peer_global(struct vty *vty, struct bgp *bgp,
 	}
 
 	/* capability software-version */
-	if (peergroup_flag_check(peer, PEER_FLAG_CAPABILITY_SOFT_VERSION))
-		vty_out(vty, " neighbor %s capability software-version\n",
-			addr);
+	if (CHECK_FLAG(bgp->flags, BGP_FLAG_SOFT_VERSION_CAPABILITY)) {
+		if (!peergroup_flag_check(peer,
+					  PEER_FLAG_CAPABILITY_SOFT_VERSION))
+			vty_out(vty,
+				" no neighbor %s capability software-version\n",
+				addr);
+	} else {
+		if (peergroup_flag_check(peer,
+					 PEER_FLAG_CAPABILITY_SOFT_VERSION))
+			vty_out(vty,
+				" neighbor %s capability software-version\n",
+				addr);
+	}
 
 	/* dont-capability-negotiation */
 	if (peergroup_flag_check(peer, PEER_FLAG_DONT_CAPABILITY))

diff --git a/bgpd/bgpd.c b/bgpd/bgpd.c
@@ -1541,6 +1541,9 @@ struct peer *peer_new(struct bgp *bgp)
 	if (CHECK_FLAG(bgp->flags, BGP_FLAG_ENFORCE_FIRST_AS))
 		SET_FLAG(peer->flags, PEER_FLAG_ENFORCE_FIRST_AS);
 
+	if (CHECK_FLAG(bgp->flags, BGP_FLAG_SOFT_VERSION_CAPABILITY))
+		SET_FLAG(peer->flags, PEER_FLAG_CAPABILITY_SOFT_VERSION);
+
 	SET_FLAG(peer->flags_invert, PEER_FLAG_CAPABILITY_FQDN);
 	SET_FLAG(peer->flags, PEER_FLAG_CAPABILITY_FQDN);