bgpd: Fix graceful-restart for peer-groups

Slipped somehow that peer-groups with GR is just completely broken, but it was
working before.

Strikes again, that we MUST have more and more topotests.

Fixes: 15403f521a ("bgpd: Streamline GR config, act on change immediately")

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

bgpd/bgp_fsm.c

@@ -2726,10 +2726,11 @@ static void bgp_gr_update_mode_of_all_peers(struct bgp *bgp,
 	struct listnode *node = {0};
 	struct listnode *nnode = {0};
 	enum peer_mode peer_old_state = PEER_INVALID;
-
+	struct peer_group *group;
-	/* TODO: Need to handle peer-groups. */
+	struct peer *member;
 
 	for (ALL_LIST_ELEMENTS(bgp->peer, node, nnode, peer)) {
+		if (!CHECK_FLAG(peer->sflags, PEER_STATUS_GROUP)) {
 			peer_old_state = bgp_peer_gr_mode_get(peer);
 			if (peer_old_state != PEER_GLOBAL_INHERIT)
 				continue;
@@ -2740,19 +2741,40 @@ static void bgp_gr_update_mode_of_all_peers(struct bgp *bgp,
 			if (BGP_DEBUG(graceful_restart, GRACEFUL_RESTART))
 				zlog_debug("%pBP: Inherited Global GR mode, GR flags 0x%x peer flags 0x%" PRIx64
 					   "...resetting session",
-				   peer, peer->peer_gr_new_status_flag,
+					   peer, peer->peer_gr_new_status_flag, peer->flags);
-				   peer->flags);
 
 			peer->last_reset = PEER_DOWN_CAPABILITY_CHANGE;
 
-		/* Reset session to match with behavior for other peer
-		 * configs that require the session to be re-setup.
-		 */
 			if (BGP_IS_VALID_STATE_FOR_NOTIF(peer->connection->status))
 				bgp_notify_send(peer->connection, BGP_NOTIFY_CEASE,
 						BGP_NOTIFY_CEASE_CONFIG_CHANGE);
 			else
 				bgp_session_reset_safe(peer, &nnode);
+		} else {
+			group = peer->group;
+			for (ALL_LIST_ELEMENTS(group->peer, node, nnode, member)) {
+				peer_old_state = bgp_peer_gr_mode_get(member);
+				if (peer_old_state != PEER_GLOBAL_INHERIT)
+					continue;
+
+				bgp_peer_inherit_global_gr_mode(member, global_new_state);
+				bgp_peer_gr_flags_update(member);
+
+				if (BGP_DEBUG(graceful_restart, GRACEFUL_RESTART))
+					zlog_debug("%pBP: Inherited Global GR mode, GR flags 0x%x peer flags 0x%" PRIx64
+						   "...resetting session",
+						   member, member->peer_gr_new_status_flag,
+						   member->flags);
+
+				member->last_reset = PEER_DOWN_CAPABILITY_CHANGE;
+
+				if (BGP_IS_VALID_STATE_FOR_NOTIF(member->connection->status))
+					bgp_notify_send(member->connection, BGP_NOTIFY_CEASE,
+							BGP_NOTIFY_CEASE_CONFIG_CHANGE);
+				else
+					bgp_session_reset(member);
+			}
+		}
 	}
 }
 
@@ -2911,6 +2933,9 @@ unsigned int bgp_peer_gr_action(struct peer *peer, enum peer_mode old_state,
 {
 	enum global_mode global_gr_mode;
 	bool session_reset = true;
+	struct peer_group *group;
+	struct peer *member;
+	struct listnode *node, *nnode;
 
 	if (old_state == new_state)
 		return BGP_GR_NO_OPERATION;
@@ -2945,16 +2970,27 @@ unsigned int bgp_peer_gr_action(struct peer *peer, enum peer_mode old_state,
 	bgp_peer_move_to_gr_mode(peer, new_state);
 
 	if (session_reset) {
+		if (!CHECK_FLAG(peer->sflags, PEER_STATUS_GROUP)) {
 			peer->last_reset = PEER_DOWN_CAPABILITY_CHANGE;
 
-		/* Reset session to match with behavior for other peer
-		 * configs that require the session to be re-setup.
-		 */
 			if (BGP_IS_VALID_STATE_FOR_NOTIF(peer->connection->status))
 				bgp_notify_send(peer->connection, BGP_NOTIFY_CEASE,
 						BGP_NOTIFY_CEASE_CONFIG_CHANGE);
 			else
 				bgp_session_reset(peer);
+		} else {
+			group = peer->group;
+			for (ALL_LIST_ELEMENTS(group->peer, node, nnode, member)) {
+				member->last_reset = PEER_DOWN_CAPABILITY_CHANGE;
+				bgp_peer_move_to_gr_mode(member, new_state);
+
+				if (BGP_IS_VALID_STATE_FOR_NOTIF(member->connection->status))
+					bgp_notify_send(member->connection, BGP_NOTIFY_CEASE,
+							BGP_NOTIFY_CEASE_CONFIG_CHANGE);
+				else
+					bgp_session_reset(member);
+			}
+		}
 	}
 
 	return BGP_GR_SUCCESS;

bgpd/bgp_vty.c

@@ -3519,11 +3519,6 @@ DEFUN (bgp_neighbor_graceful_restart_set,
 	peer = peer_and_group_lookup_vty(vty, argv[idx_peer]->arg);
 	if (!peer)
 		return CMD_WARNING_CONFIG_FAILED;
-	if (CHECK_FLAG(peer->sflags, PEER_STATUS_GROUP)) {
-		vty_out(vty,
-			"Per peer-group graceful-restart configuration is not yet supported\n");
-		return CMD_WARNING_CONFIG_FAILED;
-	}
 
 	result = bgp_neighbor_graceful_restart(peer, PEER_GR_CMD);
 	if (result == BGP_GR_SUCCESS) {
@@ -3554,11 +3549,6 @@ DEFUN (no_bgp_neighbor_graceful_restart,
 	peer = peer_and_group_lookup_vty(vty, argv[idx_peer]->arg);
 	if (!peer)
 		return CMD_WARNING_CONFIG_FAILED;
-	if (CHECK_FLAG(peer->sflags, PEER_STATUS_GROUP)) {
-		vty_out(vty,
-			"Per peer-group graceful-restart configuration is not yet supported\n");
-		return CMD_WARNING_CONFIG_FAILED;
-	}
 
 	result = bgp_neighbor_graceful_restart(peer, NO_PEER_GR_CMD);
 	if (ret == BGP_GR_SUCCESS) {
@@ -3588,11 +3578,6 @@ DEFUN (bgp_neighbor_graceful_restart_helper_set,
 	peer = peer_and_group_lookup_vty(vty, argv[idx_peer]->arg);
 	if (!peer)
 		return CMD_WARNING_CONFIG_FAILED;
-	if (CHECK_FLAG(peer->sflags, PEER_STATUS_GROUP)) {
-		vty_out(vty,
-			"Per peer-group graceful-restart configuration is not yet supported\n");
-		return CMD_WARNING_CONFIG_FAILED;
-	}
 
 	ret = bgp_neighbor_graceful_restart(peer, PEER_HELPER_CMD);
 	if (ret == BGP_GR_SUCCESS) {
@@ -3623,11 +3608,6 @@ DEFUN (no_bgp_neighbor_graceful_restart_helper,
 	peer = peer_and_group_lookup_vty(vty, argv[idx_peer]->arg);
 	if (!peer)
 		return CMD_WARNING_CONFIG_FAILED;
-	if (CHECK_FLAG(peer->sflags, PEER_STATUS_GROUP)) {
-		vty_out(vty,
-			"Per peer-group graceful-restart configuration is not yet supported\n");
-		return CMD_WARNING_CONFIG_FAILED;
-	}
 
 	ret = bgp_neighbor_graceful_restart(peer, NO_PEER_HELPER_CMD);
 	if (ret == BGP_GR_SUCCESS) {
@@ -3657,11 +3637,6 @@ DEFUN (bgp_neighbor_graceful_restart_disable_set,
 	peer = peer_and_group_lookup_vty(vty, argv[idx_peer]->arg);
 	if (!peer)
 		return CMD_WARNING_CONFIG_FAILED;
-	if (CHECK_FLAG(peer->sflags, PEER_STATUS_GROUP)) {
-		vty_out(vty,
-			"Per peer-group graceful-restart configuration is not yet supported\n");
-		return CMD_WARNING_CONFIG_FAILED;
-	}
 
 	ret = bgp_neighbor_graceful_restart(peer, PEER_DISABLE_CMD);
 	if (ret == BGP_GR_SUCCESS) {
@@ -3693,11 +3668,6 @@ DEFUN (no_bgp_neighbor_graceful_restart_disable,
 	peer = peer_and_group_lookup_vty(vty, argv[idx_peer]->arg);
 	if (!peer)
 		return CMD_WARNING_CONFIG_FAILED;
-	if (CHECK_FLAG(peer->sflags, PEER_STATUS_GROUP)) {
-		vty_out(vty,
-			"Per peer-group graceful-restart configuration is not yet supported\n");
-		return CMD_WARNING_CONFIG_FAILED;
-	}
 
 	ret = bgp_neighbor_graceful_restart(peer, NO_PEER_DISABLE_CMD);
 	if (ret == BGP_GR_SUCCESS) {

bgpd/bgpd.c

@@ -3022,6 +3022,7 @@ static void peer_group2peer_config_copy(struct peer_group *group,
 	PEER_ATTR_INHERIT(peer, group, local_role);
 
 	/* Update GR flags for the peer. */
+	PEER_ATTR_INHERIT(peer, group, peer_gr_new_status_flag);
 	bgp_peer_gr_flags_update(peer);
 
 	/* Apply BFD settings from group to peer if it exists. */