bgpd: fix no bgp as-path access-list issue

bgpd/bgp_aspath.h

@@ -65,6 +65,15 @@ struct aspath {
 
 #define ASPATH_STR_DEFAULT_LEN 32
 
+/* `set as-path exclude ASn' */
+struct aspath_exclude {
+	struct aspath *aspath;
+	bool exclude_all;
+	char *exclude_aspath_acl_name;
+	struct as_list *exclude_aspath_acl;
+};
+
+
 /* Prototypes. */
 extern void aspath_init(void);
 extern void aspath_finish(void);

bgpd/bgp_filter.c

@@ -205,8 +205,17 @@ static struct as_list *as_list_new(void)
 
 static void as_list_free(struct as_list *aslist)
 {
+	struct bp_as_excl_list *cur_bp = aslist->bp_list;
+	struct bp_as_excl_list *next_bp = NULL;
 	XFREE(MTYPE_AS_STR, aslist->name);
 	XFREE(MTYPE_AS_LIST, aslist);
+
+	while(cur_bp) {
+		next_bp = cur_bp->next;
+		XFREE(MTYPE_ROUTE_MAP_COMPILED, cur_bp);
+		cur_bp = next_bp;
+	}
+
 }
 
 /* Insert new AS list to list of as_list.  Each as_list is sorted by
@@ -290,6 +299,7 @@ static void as_list_delete(struct as_list *aslist)
 {
 	struct as_list_list *list;
 	struct as_filter *filter, *next;
+	struct bp_as_excl_list *cur_bp;
 
 	for (filter = aslist->head; filter; filter = next) {
 		next = filter->next;
@@ -308,6 +318,14 @@ static void as_list_delete(struct as_list *aslist)
 	else
 		list->head = aslist->next;
 
+	cur_bp = aslist->bp_list;
+	while (cur_bp) {
+            cur_bp->bp_as_excl->exclude_aspath_acl = NULL;
+            cur_bp = cur_bp->next;
+	}
+
+
+
 	as_list_free(aslist);
 }
 

bgpd/bgp_filter.h

@@ -25,6 +25,13 @@ struct as_filter {
 	int64_t seq;
 };
 
+
+struct bp_as_excl_list {
+	struct bp_as_excl_list *next;
+	struct aspath_exclude *bp_as_excl;
+};
+
+
 /* AS path filter list. */
 struct as_list {
 	char *name;
@@ -34,6 +41,8 @@ struct as_list {
 
 	struct as_filter *head;
 	struct as_filter *tail;
+	/* back pointer to the aspath_excludes */
+	struct bp_as_excl_list *bp_list;
 };
 
 

bgpd/bgp_routemap.c

@@ -2323,17 +2323,10 @@ static const struct route_map_rule_cmd route_set_aspath_prepend_cmd = {
 	route_set_aspath_prepend_free,
 };
 
-/* `set as-path exclude ASn' */
-struct aspath_exclude {
-	struct aspath *aspath;
-	bool exclude_all;
-	char *exclude_aspath_acl_name;
-	struct as_list *exclude_aspath_acl;
-};
-
 static void *route_aspath_exclude_compile(const char *arg)
 {
 	struct aspath_exclude *ase;
+	struct bp_as_excl_list *bp;
 	const char *str = arg;
 	static const char asp_acl[] = "as-path-access-list";
 
@@ -2348,16 +2341,37 @@ static void *route_aspath_exclude_compile(const char *arg)
 		ase->exclude_aspath_acl = as_list_lookup(str);
 	} else
 		ase->aspath = aspath_str2aspath(str, bgp_get_asnotation(NULL));
+
+	if (ase->exclude_aspath_acl) {
+		bp = XCALLOC(MTYPE_ROUTE_MAP_COMPILED,
+				sizeof(struct bp_as_excl_list));
+		bp->bp_as_excl = ase;
+		bp->next = ase->exclude_aspath_acl->bp_list;
+		ase->exclude_aspath_acl->bp_list = bp;
+	}
+
+
 	return ase;
 }
 
 static void route_aspath_exclude_free(void *rule)
 {
 	struct aspath_exclude *ase = rule;
+	struct bp_as_excl_list *cur_bp = NULL;
+	struct bp_as_excl_list *prev_bp = NULL;
 
 	aspath_free(ase->aspath);
 	if (ase->exclude_aspath_acl_name)
 		XFREE(MTYPE_TMP, ase->exclude_aspath_acl_name);
+	if (ase->exclude_aspath_acl)
+		cur_bp = ase->exclude_aspath_acl->bp_list;
+	while (cur_bp) {
+		if (cur_bp->bp_as_excl == ase) {
+			cur_bp = prev_bp;
+			XFREE(MTYPE_ROUTE_MAP_COMPILED, cur_bp);
+			break;
+		}
+	}
 	XFREE(MTYPE_ROUTE_MAP_COMPILED, ase);
 }
 

tests/topotests/bgp_set_aspath_exclude/test_bgp_set_aspath_exclude.py

@@ -22,6 +22,7 @@
 # pylint: disable=C0413
 from lib import topotest
 from lib.topogen import Topogen, TopoRouter, get_topogen
+from time import sleep
 
 
 pytestmark = [pytest.mark.bgpd]
@@ -134,12 +135,66 @@ def _bgp_regexp_1(router):
         }
     }
 
+    # tgen.mininet_cli()
     test_func = functools.partial(_bgp_regexp_1, tgen.gears["r1"])
     _, result = topotest.run_and_expect(test_func, None, count=30, wait=0.5)
 
     assert result is None, "Failed overriding incoming AS-PATH with regex 2 route-map"
 
 
+def test_no_bgp_set_aspath_exclude_access_list():
+    tgen = get_topogen()
+
+    if tgen.routers_have_failure():
+        pytest.skip(tgen.errors)
+
+    rname = "r1"
+    r1 = tgen.gears[rname]
+
+    r1.vtysh_cmd(
+        """
+conf
+ no bgp as-path access-list SECOND permit 2 
+    """
+    )
+
+    expected = {
+        "routes": {
+            "172.16.255.31/32": [{"path": "65003"}],
+            "172.16.255.32/32": [{"path": "65003"}],
+        }
+    }
+
+    def _bgp_regexp_2(router):
+        output = json.loads(router.vtysh_cmd("show bgp ipv4 unicast json"))
+
+        return topotest.json_cmp(output, expected)
+
+    test_func = functools.partial(_bgp_regexp_2, tgen.gears["r1"])
+    _, result = topotest.run_and_expect(test_func, None, count=30, wait=0.5)
+
+    assert result is None, "Failed removing bgp as-path access-list"
+
+    r1.vtysh_cmd(
+        """
+clear bgp *
+    """
+    )
+
+    expected = {
+        "routes": {
+            "172.16.255.31/32": [{"path": "65002 65003"}],
+            "172.16.255.32/32": [{"path": "65002 65003"}],
+        }
+    }
+    sleep(10)
+
+    test_func = functools.partial(_bgp_regexp_2, tgen.gears["r1"])
+    _, result = topotest.run_and_expect(test_func, None, count=30, wait=0.5)
+
+    assert result is None, "Failed to renegociate with peers"
+
+
 if __name__ == "__main__":
     args = ["-s"] + sys.argv[1:]
     sys.exit(pytest.main(args))