Merge pull request #15233 from louis-6wind/bgp-leak-no-network

bgpd: fix VRF leaking with 'no bgp network import-check'

bgpd/bgp_mplsvpn.c

@@ -1011,9 +1011,11 @@ static bool leak_update_nexthop_valid(struct bgp *to_bgp, struct bgp_dest *bn,
 {
 	struct bgp_path_info *bpi_ultimate;
 	struct bgp *bgp_nexthop;
+	struct bgp_table *table;
 	bool nh_valid;
 
 	bpi_ultimate = bgp_get_imported_bpi_ultimate(source_bpi);
+	table = bgp_dest_table(bpi_ultimate->net);
 
 	if (bpi->extra && bpi->extra->vrfleak && bpi->extra->vrfleak->bgp_orig)
 		bgp_nexthop = bpi->extra->vrfleak->bgp_orig;
@@ -1029,7 +1031,17 @@ static bool leak_update_nexthop_valid(struct bgp *to_bgp, struct bgp_dest *bn,
 	    is_pi_family_evpn(bpi_ultimate) ||
 	    CHECK_FLAG(bpi_ultimate->flags, BGP_PATH_ACCEPT_OWN))
 		nh_valid = true;
-	else
+	else if (bpi_ultimate->type == ZEBRA_ROUTE_BGP &&
+		 bpi_ultimate->sub_type == BGP_ROUTE_STATIC && table &&
+		 (table->safi == SAFI_UNICAST ||
+		  table->safi == SAFI_LABELED_UNICAST) &&
+		 !CHECK_FLAG(bgp_nexthop->flags, BGP_FLAG_IMPORT_CHECK)) {
+		/* if the route is defined with the "network <prefix>" command
+		 * and "no bgp network import-check" is set,
+		 * then mark the nexthop as valid.
+		 */
+		nh_valid = true;
+	} else
 		/*
 		 * TBD do we need to do anything about the
 		 * 'connected' parameter?

tests/topotests/bgp_l3vpn_to_bgp_vrf/customize.py

@@ -161,6 +161,15 @@ def ltemplatePreRouterStartHook():
         logger.info(
             "setup {0} vrf {0}-cust1, {0}-eth4. enabled mpls input.".format(rtr)
         )
+    # configure cust4 VRFs & MPLS
+    cmds = [
+        "ip link add {0}-cust4 type vrf table 30",
+        "ip link set dev {0}-cust4 up",
+    ]
+    rtr = "r1"
+    for cmd in cmds:
+        cc.doCmd(tgen, rtr, cmd.format(rtr))
+    logger.info("setup {0} vrf {0}-cust3 and{0}-cust4.".format(rtr))
     # configure cust2 VRFs & MPLS
     rtrs = ["r4"]
     cmds = [

tests/topotests/bgp_l3vpn_to_bgp_vrf/r1/bgpd.conf

@@ -50,6 +50,19 @@ router bgp 5227 vrf r1-cust1
      export vpn
    exit-address-family
 
+router bgp 5227 vrf r1-cust4
+   no bgp network import-check
 
+   bgp router-id 192.168.1.1
+
+   address-family ipv4 unicast
+     network 172.16.0.0/24
+
+     rd vpn export 10:14
+     rt vpn export 52:100
+
+     import vpn
+     export vpn
+   exit-address-family
 !
 end

tests/topotests/bgp_l3vpn_to_bgp_vrf/scripts/check_routes.py

@@ -59,12 +59,20 @@ want_r1_cust1_routes = [
     {"p": "5.1.1.0/24", "n": "99.0.0.1"},
     {"p": "6.0.1.0/24", "n": "99.0.0.1"},
     {"p": "6.0.2.0/24", "n": "99.0.0.1"},
+    {"p": "172.16.0.0/24", "n": "0.0.0.0", "bp": True},
     {"p": "99.0.0.1/32", "n": "192.168.1.2"},
 ]
 bgpribRequireUnicastRoutes(
     "r1", "ipv4", "r1-cust1", "Customer 1 routes in r1 vrf", want_r1_cust1_routes
 )
 
+want_r1_cust4_routes = [
+    {"p": "172.16.0.0/24", "n": "0.0.0.0", "bp": True},
+]
+bgpribRequireUnicastRoutes(
+    "r1", "ipv4", "r1-cust4", "Customer 4 routes in r1 vrf", want_r1_cust4_routes
+)
+
 want_r3_cust1_routes = [
     {"p": "5.1.0.0/24", "n": "99.0.0.2"},
     {"p": "5.1.1.0/24", "n": "99.0.0.2"},
@@ -667,7 +675,7 @@ bgpribRequireUnicastRoutes(
 luCommand(
     "ce1",
     'vtysh -c "show bgp ipv4 uni"',
-    "12 routes and 12",
+    "13 routes and 13",
     "wait",
     "Local and remote routes",
     10,
@@ -689,7 +697,7 @@ bgpribRequireUnicastRoutes(
 luCommand(
     "ce2",
     'vtysh -c "show bgp ipv4 uni"',
-    "12 routes and 15",
+    "13 routes and 16",
     "wait",
     "Local and remote routes",
     10,
@@ -721,7 +729,7 @@ luCommand("r4", 'vtysh -c "show ip route vrf r4-cust2"')
 luCommand(
     "ce3",
     'vtysh -c "show bgp ipv4 uni"',
-    "12 routes and 13",
+    "13 routes and 14",
     "wait",
     "Local and remote routes",
     10,
@@ -743,7 +751,7 @@ bgpribRequireUnicastRoutes(
 luCommand(
     "ce4",
     'vtysh -c "show bgp vrf ce4-cust2 ipv4 uni"',
-    "12 routes and 14",
+    "13 routes and 15",
     "wait",
     "Local and remote routes",
     10,

tests/topotests/bgp_l3vpn_to_bgp_vrf/scripts/scale_down.py

@@ -49,7 +49,7 @@ if ret != False and found != None:
             luCommand(
                 rtr,
                 'vtysh -c "show bgp ipv4 uni" | grep Display',
-                " 12 route",
+                " 13 route",
                 "wait",
                 "BGP routes removed",
                 wait,