Merge pull request #8701 from ton31337/feature/show_ip_bgp_alias

bgpd: Show BGP prefixes by community alias

bgpd/bgp_community.c

@@ -451,9 +451,11 @@ static void set_community_string(struct community *com, bool make_json)
 			val = comval & 0xFFFF;
 			char buf[32];
 			snprintf(buf, sizeof(buf), "%u:%d", as, val);
-			strlcat(str, bgp_community2alias(buf), len);
+			const char *com2alias = bgp_community2alias(buf);
+
+			strlcat(str, com2alias, len);
 			if (make_json) {
-				json_string = json_object_new_string(buf);
+				json_string = json_object_new_string(com2alias);
 				json_object_array_add(json_community_list,
 						      json_string);
 			}

bgpd/bgp_lcommunity.c

@@ -232,11 +232,13 @@ static void set_lcommunity_string(struct lcommunity *lcom, bool make_json)
 		snprintf(lcsb, sizeof(lcsb), "%u:%u:%u", global, local1,
 			 local2);
 
-		len = strlcat(str_buf, bgp_community2alias(lcsb), str_buf_sz);
+		const char *com2alias = bgp_community2alias(lcsb);
+
+		len = strlcat(str_buf, com2alias, str_buf_sz);
 		assert((unsigned int)len < str_buf_sz);
 
 		if (make_json) {
-			json_string = json_object_new_string(lcsb);
+			json_string = json_object_new_string(com2alias);
 			json_object_array_add(json_lcommunity_list,
 					      json_string);
 		}

bgpd/bgp_route.c

@@ -23,6 +23,7 @@
 #include <math.h>
 
 #include "printfrr.h"
+#include "frrstr.h"
 #include "prefix.h"
 #include "linklist.h"
 #include "memory.h"
@@ -10570,7 +10571,6 @@ static int bgp_show_community(struct vty *vty, struct bgp *bgp,
 			      const char *comstr, int exact, afi_t afi,
 			      safi_t safi, uint8_t show_flags);
 
-
 static int bgp_show_table(struct vty *vty, struct bgp *bgp, safi_t safi,
 			  struct bgp_table *table, enum bgp_show_type type,
 			  void *output_arg, char *rd, int is_last,
@@ -10647,6 +10647,48 @@ static int bgp_show_table(struct vty *vty, struct bgp *bgp, safi_t safi,
 					continue;
 			}
 
+			if (type == bgp_show_type_community_alias) {
+				char *alias = output_arg;
+				char **communities;
+				int num;
+				bool found = false;
+
+				if (pi->attr->community) {
+					frrstr_split(pi->attr->community->str,
+						     " ", &communities, &num);
+					for (int i = 0; i < num; i++) {
+						const char *com2alias =
+							bgp_community2alias(
+								communities[i]);
+						if (strncmp(alias, com2alias,
+							    strlen(com2alias))
+						    == 0) {
+							found = true;
+							break;
+						}
+					}
+				}
+
+				if (!found && pi->attr->lcommunity) {
+					frrstr_split(pi->attr->lcommunity->str,
+						     " ", &communities, &num);
+					for (int i = 0; i < num; i++) {
+						const char *com2alias =
+							bgp_community2alias(
+								communities[i]);
+						if (strncmp(alias, com2alias,
+							    strlen(com2alias))
+						    == 0) {
+							found = true;
+							break;
+						}
+					}
+				}
+
+				if (!found)
+					continue;
+			}
+
 			if (type == bgp_show_type_rpki) {
 				if (dest_p->family == AF_INET
 				    || dest_p->family == AF_INET6)
@@ -11920,9 +11962,10 @@ DEFPY(show_ip_bgp, show_ip_bgp_cmd,
 }
 
 /* BGP route print out function with JSON */
-DEFPY (show_ip_bgp_json,
+DEFPY(show_ip_bgp_json, show_ip_bgp_json_cmd,
-       show_ip_bgp_json_cmd,
+      "show [ip] bgp [<view|vrf> VIEWVRFNAME] [" BGP_AFI_CMD_STR
-       "show [ip] bgp [<view|vrf> VIEWVRFNAME] ["BGP_AFI_CMD_STR" ["BGP_SAFI_WITH_LABEL_CMD_STR"]]\
+      " [" BGP_SAFI_WITH_LABEL_CMD_STR
+      "]]\
           [all$all]\
           [cidr-only\
           |dampening <flap-statistics|dampened-paths>\
@@ -11933,20 +11976,16 @@ DEFPY (show_ip_bgp_json,
                      |route-filter-translated-v4] [exact-match]\
           |rpki <invalid|valid|notfound>\
           |version (1-4294967295)\
+          |alias WORD\
           ] [json$uj [detail$detail] | wide$wide]",
-       SHOW_STR
+      SHOW_STR IP_STR BGP_STR BGP_INSTANCE_HELP_STR BGP_AFI_HELP_STR
-       IP_STR
-       BGP_STR
-       BGP_INSTANCE_HELP_STR
-       BGP_AFI_HELP_STR
 	      BGP_SAFI_WITH_LABEL_HELP_STR
       "Display the entries for all address families\n"
       "Display only routes with non-natural netmasks\n"
       "Display detailed information about dampening\n"
       "Display flap statistics of routes\n"
       "Display paths suppressed due to dampening\n"
-       "Display routes matching the communities\n"
+      "Display routes matching the communities\n" COMMUNITY_AANN_STR
-       COMMUNITY_AANN_STR
       "Do not send outside local AS (well-known community)\n"
       "Do not advertise to any peer (well-known community)\n"
       "Do not export to next AS (well-known community)\n"
@@ -11968,7 +12007,8 @@ DEFPY (show_ip_bgp_json,
       "A path that has no rpki data\n"
       "Display prefixes with matching version numbers\n"
       "Version number and above\n"
-       JSON_STR
+      "Display prefixes with matching BGP community alias\n"
+      "BGP community alias\n" JSON_STR
       "Display detailed version of JSON output\n"
       "Increase table width for longer prefixes\n")
 {
@@ -11980,6 +12020,7 @@ DEFPY (show_ip_bgp_json,
 	int exact_match = 0;
 	char *community = NULL;
 	char *prefix_version = NULL;
+	char *bgp_community_alias = NULL;
 	bool first = true;
 	uint8_t show_flags = 0;
 	enum rpki_states rpki_target_state = RPKI_NOT_BEING_USED;
@@ -12056,6 +12097,12 @@ DEFPY (show_ip_bgp_json,
 		prefix_version = argv[idx + 1]->arg;
 	}
 
+	/* Display prefixes with matching BGP community alias */
+	if (argv_find(argv, argc, "alias", &idx)) {
+		sh_type = bgp_show_type_community_alias;
+		bgp_community_alias = argv[idx + 1]->arg;
+	}
+
 	if (!all) {
 		/* show bgp: AFI_IP6, show ip bgp: AFI_IP */
 		if (community)
@@ -12066,6 +12113,10 @@ DEFPY (show_ip_bgp_json,
 			return bgp_show(vty, bgp, afi, safi, sh_type,
 					prefix_version, show_flags,
 					rpki_target_state);
+		else if (bgp_community_alias)
+			return bgp_show(vty, bgp, afi, safi, sh_type,
+					bgp_community_alias, show_flags,
+					rpki_target_state);
 		else
 			return bgp_show(vty, bgp, afi, safi, sh_type, NULL,
 					show_flags, rpki_target_state);
@@ -12108,6 +12159,11 @@ DEFPY (show_ip_bgp_json,
 							sh_type, prefix_version,
 							show_flags,
 							rpki_target_state);
+				else if (bgp_community_alias)
+					return bgp_show(
+						vty, bgp, afi, safi, sh_type,
+						bgp_community_alias, show_flags,
+						rpki_target_state);
 				else
 					bgp_show(vty, bgp, afi, safi, sh_type,
 						 NULL, show_flags,

bgpd/bgp_route.h

@@ -42,6 +42,7 @@ enum bgp_show_type {
 	bgp_show_type_neighbor,
 	bgp_show_type_cidr_only,
 	bgp_show_type_prefix_longer,
+	bgp_show_type_community_alias,
 	bgp_show_type_community_all,
 	bgp_show_type_community,
 	bgp_show_type_community_exact,

doc/user/bgp.rst

@@ -2111,6 +2111,10 @@ things on the wire.
             Large Community: lcommunity-1 65001:123:2
             Last update: Fri Apr 16 12:51:27 2021
 
+.. clicmd:: show bgp [afi] [safi] [all] alias WORD [wide|json]
+
+   Display prefixes with matching BGP community alias.
+
 .. _bgp-using-communities-in-route-map:
 
 Using Communities in Route Maps

tests/topotests/bgp_community_alias/r1/bgpd.conf

@@ -1,7 +1,7 @@
 !
-bgp community alias 65002:1 community-r2-1
+bgp community alias 65001:1 community-r2-1
 bgp community alias 65002:2 community-r2-2
-bgp community alias 65002:1:1 large-community-r2-1
+bgp community alias 65001:1:1 large-community-r2-1
 !
 router bgp 65001
  no bgp ebgp-requires-policy

tests/topotests/bgp_community_alias/r2/bgpd.conf

@@ -6,7 +6,14 @@ router bgp 65002
   neighbor 192.168.1.1 route-map r1 out
  exit-address-family
 !
-route-map r1 permit 10
+ip prefix-list p1 permit 172.16.16.1/32
- set community 65002:1 65002:2
+ip prefix-list p2 permit 172.16.16.2/32
- set large-community 65002:1:1 65002:2:1
+!
+route-map r1 permit 10
+ match ip address prefix-list p1
+ set community 65001:1 65001:2
+ set large-community 65001:1:1 65001:1:2
+route-map r1 permit 20
+ match ip address prefix-list p2
+ set community 65002:1 65002:2
 !

tests/topotests/bgp_community_alias/r2/zebra.conf

@@ -1,4 +1,8 @@
 !
+int lo
+ ip address 172.16.16.1/32
+ ip address 172.16.16.2/32
+!
 int r2-eth0
  ip address 192.168.1.2/24
 !

tests/topotests/bgp_community_alias/test_bgp-community-alias.py

@@ -84,12 +84,14 @@ def test_bgp_community_alias():
     router = tgen.gears["r1"]
 
     def _bgp_converge(router):
-        output = json.loads(router.vtysh_cmd("show ip bgp 192.168.1.0/24 json"))
+        output = json.loads(
+            router.vtysh_cmd("show bgp ipv4 unicast 172.16.16.1/32 json")
+        )
         expected = {
             "paths": [
                 {
-                    "community": {"string": "community-r2-1 community-r2-2"},
+                    "community": {"string": "community-r2-1 65001:2"},
-                    "largeCommunity": {"string": "large-community-r2-1 65002:2:1"},
+                    "largeCommunity": {"string": "large-community-r2-1 65001:1:2"},
                 }
             ]
         }
@@ -97,9 +99,25 @@ def test_bgp_community_alias():
 
     test_func = functools.partial(_bgp_converge, router)
     success, result = topotest.run_and_expect(test_func, None, count=60, wait=0.5)
-
     assert result is None, 'Cannot see BGP community aliases "{}"'.format(router)
 
+    def _bgp_show_prefixes_by_alias(router):
+        output = json.loads(
+            router.vtysh_cmd("show bgp ipv4 unicast alias community-r2-2 json detail")
+        )
+        expected = {
+            "routes": {
+                "172.16.16.2/32": [{"community": {"string": "65002:1 community-r2-2"}}]
+            }
+        }
+        return topotest.json_cmp(output, expected)
+
+    test_func = functools.partial(_bgp_show_prefixes_by_alias, router)
+    success, result = topotest.run_and_expect(test_func, None, count=60, wait=0.5)
+    assert result is None, 'Cannot see BGP prefixes by community alias "{}"'.format(
+        router
+    )
+
 
 if __name__ == "__main__":
     args = ["-s"] + sys.argv[1:]