Merge pull request #12678 from opensourcerouting/fix/missing_no_form_for_path_attribute_discard

bgpd: Add missing `no` form for `neighbor path-attribute discard` cmd

3 files changed, 46 insertions, 7 deletions

diff --git a/bgpd/bgp_attr.c b/bgpd/bgp_attr.c
index e60c1bb8d..392b55880 100644
--- a/bgpd/bgp_attr.c
+++ b/bgpd/bgp_attr.c
@@ -5097,18 +5097,29 @@ void bgp_dump_routes_attr(struct stream *s, struct bgp_path_info *bpi,
 }
 
 void bgp_path_attribute_discard_vty(struct vty *vty, struct peer *peer,
-				    const char *discard_attrs)
+				    const char *discard_attrs, bool set)
 {
 	int i, num_attributes;
 	char **attributes;
 	afi_t afi;
 	safi_t safi;
 
-	if (discard_attrs) {
-		frrstr_split(discard_attrs, " ", &attributes, &num_attributes);
 
+	/* If `no` command specified without arbitrary attributes,
+	 * then flush all.
+	 */
+	if (!discard_attrs) {
 		for (i = 0; i < BGP_ATTR_MAX; i++)
 			peer->discard_attrs[i] = false;
+		goto discard_soft_clear;
+	}
+
+	if (discard_attrs) {
+		frrstr_split(discard_attrs, " ", &attributes, &num_attributes);
+
+		if (set)
+			for (i = 0; i < BGP_ATTR_MAX; i++)
+				peer->discard_attrs[i] = false;
 
 		for (i = 0; i < num_attributes; i++) {
 			uint8_t attr_num = strtoul(attributes[i], NULL, 10);
@@ -5142,10 +5153,10 @@ void bgp_path_attribute_discard_vty(struct vty *vty, struct peer *peer,
 				continue;
 			}
 
-			peer->discard_attrs[attr_num] = true;
+			peer->discard_attrs[attr_num] = set;
 		}
 		XFREE(MTYPE_TMP, attributes);
-
+	discard_soft_clear:
 		/* Configuring path attributes to be discarded will trigger
 		 * an inbound Route Refresh to ensure that the routing table
 		 * is up to date.
diff --git a/bgpd/bgp_attr.h b/bgpd/bgp_attr.h
index cb0bf4a43..33283f4bf 100644
--- a/bgpd/bgp_attr.h
+++ b/bgpd/bgp_attr.h
@@ -415,7 +415,7 @@ extern void attr_show_all(struct vty *vty);
 extern unsigned long int attr_count(void);
 extern unsigned long int attr_unknown_count(void);
 extern void bgp_path_attribute_discard_vty(struct vty *vty, struct peer *peer,
-					   const char *discard_attrs);
+					   const char *discard_attrs, bool set);
 
 /* Cluster list prototypes. */
 extern bool cluster_loop_check(struct cluster_list *cluster,
diff --git a/bgpd/bgp_vty.c b/bgpd/bgp_vty.c
index 5772900ce..5738d9ef6 100644
--- a/bgpd/bgp_vty.c
+++ b/bgpd/bgp_vty.c
@@ -8787,7 +8787,34 @@ DEFPY(neighbor_path_attribute_discard,
 	if (idx)
 		discard_attrs = argv_concat(argv, argc, idx);
 
-	bgp_path_attribute_discard_vty(vty, peer, discard_attrs);
+	bgp_path_attribute_discard_vty(vty, peer, discard_attrs, true);
+
+	return CMD_SUCCESS;
+}
+
+DEFPY(no_neighbor_path_attribute_discard,
+      no_neighbor_path_attribute_discard_cmd,
+      "no neighbor <A.B.C.D|X:X::X:X|WORD>$neighbor path-attribute discard [(1-255)]",
+      NO_STR
+      NEIGHBOR_STR
+      NEIGHBOR_ADDR_STR2
+      "Manipulate path attributes from incoming UPDATE messages\n"
+      "Drop specified attributes from incoming UPDATE messages\n"
+      "Attribute number\n")
+{
+	struct peer *peer;
+	int idx = 0;
+	const char *discard_attrs = NULL;
+
+	peer = peer_and_group_lookup_vty(vty, neighbor);
+	if (!peer)
+		return CMD_WARNING_CONFIG_FAILED;
+
+	argv_find(argv, argc, "(1-255)", &idx);
+	if (idx)
+		discard_attrs = argv[idx]->arg;
+
+	bgp_path_attribute_discard_vty(vty, peer, discard_attrs, false);
 
 	return CMD_SUCCESS;
 }
@@ -19541,6 +19568,7 @@ void bgp_vty_init(void)
 
 	/* "neighbor path-attribute discard" commands. */
 	install_element(BGP_NODE, &neighbor_path_attribute_discard_cmd);
+	install_element(BGP_NODE, &no_neighbor_path_attribute_discard_cmd);
 
 	/* "neighbor passive" commands. */
 	install_element(BGP_NODE, &neighbor_passive_cmd);