Merge pull request FRRouting#17196 from FRRouting/mergify/bp/stable/1…

…0.1/pr-17165

bgpd: Do not filter no-export community for BGP OAD (backport FRRouting#17165)

bgpd/bgp_route.c

@@ -1780,14 +1780,13 @@ static bool bgp_community_filter(struct peer *peer, struct attr *attr)
 			return true;
 
 		/* NO_EXPORT check. */
-		if (peer->sort == BGP_PEER_EBGP &&
-		    community_include(bgp_attr_get_community(attr),
-				      COMMUNITY_NO_EXPORT))
+		if (peer->sort == BGP_PEER_EBGP && peer->sub_sort != BGP_PEER_EBGP_OAD &&
+		    community_include(bgp_attr_get_community(attr), COMMUNITY_NO_EXPORT))
 			return true;
 
 		/* NO_EXPORT_SUBCONFED check. */
-		if (peer->sort == BGP_PEER_EBGP
-		    || peer->sort == BGP_PEER_CONFED)
+		if ((peer->sort == BGP_PEER_EBGP && peer->sub_sort != BGP_PEER_EBGP_OAD) ||
+		    peer->sort == BGP_PEER_CONFED)
 			if (community_include(bgp_attr_get_community(attr),
 					      COMMUNITY_NO_EXPORT_SUBCONFED))
 				return true;

tests/topotests/bgp_oad/r1/frr.conf

@@ -4,6 +4,7 @@ int r1-eth0
 !
 router bgp 65001
  no bgp ebgp-requires-policy
+ no bgp network import-check
  neighbor 192.168.1.2 remote-as external
  neighbor 192.168.1.2 timers 1 3
  neighbor 192.168.1.2 timers connect 1
@@ -12,10 +13,14 @@ router bgp 65001
  neighbor 192.168.1.4 timers 1 3
  neighbor 192.168.1.4 timers connect 1
  address-family ipv4 unicast
+  network 10.10.10.1/32 route-map local
   neighbor 192.168.1.4 route-map r4 in
  exit-address-family
 !
 route-map r4 permit 10
  set local-preference 123
  set metric 123
-exit
+!
+route-map local permit 10
+ set community no-export
+!

tests/topotests/bgp_oad/test_bgp_oad.py

@@ -8,6 +8,8 @@
 """
 Test if local-preference is passed between different EBGP peers when
 EBGP-OAD is configured.
+
+Also check if no-export community is passed to the EBGP-OAD peer.
 """
 
 import os
@@ -53,6 +55,9 @@ def test_bgp_dynamic_capability_role():
         pytest.skip(tgen.errors)
 
     r1 = tgen.gears["r1"]
+    r2 = tgen.gears["r2"]
+    r3 = tgen.gears["r3"]
+    r4 = tgen.gears["r4"]
 
     def _bgp_converge():
         output = json.loads(r1.vtysh_cmd("show bgp ipv4 unicast 10.10.10.10/32 json"))
@@ -87,6 +92,37 @@ def _bgp_converge():
     _, result = topotest.run_and_expect(test_func, None, count=30, wait=1)
     assert result is None, "Can't converge"
 
+    def _bgp_check_no_export(router, arg=[{"valid": True}]):
+        output = json.loads(router.vtysh_cmd("show bgp ipv4 unicast json"))
+        expected = {
+            "routes": {
+                "10.10.10.1/32": arg,
+            }
+        }
+        return topotest.json_cmp(output, expected)
+
+    test_func = functools.partial(
+        _bgp_check_no_export,
+        r2,
+    )
+    _, result = topotest.run_and_expect(test_func, None, count=30, wait=1)
+    assert result is None, "10.10.10.1/32 should be advertised to r2"
+
+    test_func = functools.partial(
+        _bgp_check_no_export,
+        r3,
+    )
+    _, result = topotest.run_and_expect(test_func, None, count=30, wait=1)
+    assert result is None, "10.10.10.1/32 should be advertised to r3"
+
+    test_func = functools.partial(
+        _bgp_check_no_export,
+        r4,
+        None,
+    )
+    _, result = topotest.run_and_expect(test_func, None, count=30, wait=1)
+    assert result is None, "10.10.10.1/32 should not be advertised to r4 (not OAD peer)"
+
 
 if __name__ == "__main__":
     args = ["-s"] + sys.argv[1:]