Merge pull request #5393 from ton31337/fix/update_rib_on_bgp_distance…

…_changes_7.1

bgpd: [7.1] Reflect the distance in RIB when it is changed for an arbitrary afi/safi

bgpd/bgp_route.c

@@ -11625,6 +11625,32 @@ uint8_t bgp_distance_apply(struct prefix *p, struct bgp_path_info *pinfo,
 	}
 }
 
+/* If we enter `distance bgp (1-255) (1-255) (1-255)`,
+ * we should tell ZEBRA update the routes for a specific
+ * AFI/SAFI to reflect changes in RIB.
+ */
+static void bgp_announce_routes_distance_update(struct bgp *bgp,
+						afi_t update_afi,
+						safi_t update_safi)
+{
+	afi_t afi;
+	safi_t safi;
+
+	FOREACH_AFI_SAFI (afi, safi) {
+		if (!bgp_fibupd_safi(safi))
+			continue;
+
+		if (afi != update_afi && safi != update_safi)
+			continue;
+
+		if (BGP_DEBUG(zebra, ZEBRA))
+			zlog_debug(
+				"%s: Announcing routes due to distance change afi/safi (%d/%d)",
+				__func__, afi, safi);
+		bgp_zebra_announce_table(bgp, afi, safi);
+	}
+}
+
 DEFUN (bgp_distance,
        bgp_distance_cmd,
        "distance bgp (1-255) (1-255) (1-255)",
@@ -11638,15 +11664,23 @@ DEFUN (bgp_distance,
 	int idx_number = 2;
 	int idx_number_2 = 3;
 	int idx_number_3 = 4;
+	int distance_ebgp = atoi(argv[idx_number]->arg);
+	int distance_ibgp = atoi(argv[idx_number_2]->arg);
+	int distance_local = atoi(argv[idx_number_3]->arg);
 	afi_t afi;
 	safi_t safi;
 
 	afi = bgp_node_afi(vty);
 	safi = bgp_node_safi(vty);
 
-	bgp->distance_ebgp[afi][safi] = atoi(argv[idx_number]->arg);
-	bgp->distance_ibgp[afi][safi] = atoi(argv[idx_number_2]->arg);
-	bgp->distance_local[afi][safi] = atoi(argv[idx_number_3]->arg);
+	if (bgp->distance_ebgp[afi][safi] != distance_ebgp
+	    || bgp->distance_ibgp[afi][safi] != distance_ibgp
+	    || bgp->distance_local[afi][safi] != distance_local) {
+		bgp->distance_ebgp[afi][safi] = distance_ebgp;
+		bgp->distance_ibgp[afi][safi] = distance_ibgp;
+		bgp->distance_local[afi][safi] = distance_local;
+		bgp_announce_routes_distance_update(bgp, afi, safi);
+	}
 	return CMD_SUCCESS;
 }
 
@@ -11667,9 +11701,14 @@ DEFUN (no_bgp_distance,
 	afi = bgp_node_afi(vty);
 	safi = bgp_node_safi(vty);
 
-	bgp->distance_ebgp[afi][safi] = 0;
-	bgp->distance_ibgp[afi][safi] = 0;
-	bgp->distance_local[afi][safi] = 0;
+	if (bgp->distance_ebgp[afi][safi] != 0
+	    || bgp->distance_ibgp[afi][safi] != 0
+	    || bgp->distance_local[afi][safi] != 0) {
+		bgp->distance_ebgp[afi][safi] = 0;
+		bgp->distance_ibgp[afi][safi] = 0;
+		bgp->distance_local[afi][safi] = 0;
+		bgp_announce_routes_distance_update(bgp, afi, safi);
+	}
 	return CMD_SUCCESS;
 }
 

tests/topotests/bgp_distance_change/r1/bgpd.conf

@@ -0,0 +1,4 @@
+router bgp 65000
+  neighbor 192.168.255.2 remote-as 65001
+  exit-address-family
+!

tests/topotests/bgp_distance_change/r1/zebra.conf

@@ -0,0 +1,6 @@
+!
+interface r1-eth0
+  ip address 192.168.255.1/24
+!
+ip forwarding
+!

tests/topotests/bgp_distance_change/r2/bgpd.conf

@@ -0,0 +1,6 @@
+router bgp 65001
+  neighbor 192.168.255.1 remote-as 65000
+  address-family ipv4
+    redistribute connected
+  exit-address-family
+!

tests/topotests/bgp_distance_change/r2/zebra.conf

@@ -0,0 +1,9 @@
+!
+interface lo
+  ip address 172.16.255.254/32
+!
+interface r2-eth0
+  ip address 192.168.255.2/24
+!
+ip forwarding
+!

tests/topotests/bgp_distance_change/test_bgp_distance_change.py

@@ -0,0 +1,141 @@
+#!/usr/bin/env python
+
+#
+# bgp_distance_change.py
+# Part of NetDEF Topology Tests
+#
+# Copyright (c) 2019 by
+# Donatas Abraitis <donatas.abraitis@gmail.com>
+#
+# Permission to use, copy, modify, and/or distribute this software
+# for any purpose with or without fee is hereby granted, provided
+# that the above copyright notice and this permission notice appear
+# in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND NETDEF DISCLAIMS ALL WARRANTIES
+# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NETDEF BE LIABLE FOR
+# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY
+# DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+# WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+# ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+# OF THIS SOFTWARE.
+#
+
+"""
+bgp_distance_change.py:
+
+Test if works the following commands:
+router bgp 65031
+  address-family ipv4 unicast
+    distance bgp 123 123 123
+
+Changed distance should reflect to RIB after changes.
+"""
+
+import os
+import sys
+import json
+import time
+import pytest
+import functools
+
+CWD = os.path.dirname(os.path.realpath(__file__))
+sys.path.append(os.path.join(CWD, '../'))
+
+# pylint: disable=C0413
+from lib import topotest
+from lib.topogen import Topogen, TopoRouter, get_topogen
+from lib.topolog import logger
+from mininet.topo import Topo
+
+class TemplateTopo(Topo):
+    def build(self, *_args, **_opts):
+        tgen = get_topogen(self)
+
+        for routern in range(1, 3):
+            tgen.add_router('r{}'.format(routern))
+
+        switch = tgen.add_switch('s1')
+        switch.add_link(tgen.gears['r1'])
+        switch.add_link(tgen.gears['r2'])
+
+def setup_module(mod):
+    tgen = Topogen(TemplateTopo, mod.__name__)
+    tgen.start_topology()
+
+    router_list = tgen.routers()
+
+    for i, (rname, router) in enumerate(router_list.iteritems(), 1):
+        router.load_config(
+            TopoRouter.RD_ZEBRA,
+            os.path.join(CWD, '{}/zebra.conf'.format(rname))
+        )
+        router.load_config(
+            TopoRouter.RD_BGP,
+            os.path.join(CWD, '{}/bgpd.conf'.format(rname))
+        )
+
+    tgen.start_router()
+
+def teardown_module(mod):
+    tgen = get_topogen()
+    tgen.stop_topology()
+
+def test_bgp_maximum_prefix_invalid():
+    tgen = get_topogen()
+
+    if tgen.routers_have_failure():
+        pytest.skip(tgen.errors)
+
+    router = tgen.gears['r1']
+
+    def _bgp_converge(router):
+        output = json.loads(router.vtysh_cmd("show ip bgp neighbor 192.168.255.2 json"))
+        expected = {
+            '192.168.255.2': {
+                'bgpState': 'Established',
+                'addressFamilyInfo': {
+                    'IPv4 Unicast': {
+                        'acceptedPrefixCounter': 2
+                    }
+                }
+            }
+        }
+        return topotest.json_cmp(output, expected)
+
+    def _bgp_distance_change(router):
+        router.vtysh_cmd("""
+          configure terminal
+            router bgp 65000
+              address-family ipv4 unicast
+                distance bgp 123 123 123
+        """)
+
+    def _bgp_check_distance_change(router):
+        output = json.loads(router.vtysh_cmd("show ip route 172.16.255.254/32 json"))
+        expected = {
+            '172.16.255.254/32': [
+                {
+                    'protocol': 'bgp',
+                    'distance': 123
+                }
+            ]
+        }
+        return topotest.json_cmp(output, expected)
+
+    test_func = functools.partial(_bgp_converge, router)
+    success, result = topotest.run_and_expect(test_func, None, count=15, wait=0.5)
+
+    assert result is None, 'Failed to see BGP convergence in "{}"'.format(router)
+
+    _bgp_distance_change(router)
+
+    test_func = functools.partial(_bgp_check_distance_change, router)
+    success, result = topotest.run_and_expect(test_func, None, count=15, wait=0.5)
+
+    assert result is None, 'Failed to see applied BGP distance in RIB "{}"'.format(router)
+
+if __name__ == '__main__':
+    args = ["-s"] + sys.argv[1:]
+    sys.exit(pytest.main(args))