tests: Add a test to show that BGP does not crash with unnumbered interfaces

This series of events will crash BGP prior to the prior commit:

a) Configure an interfaced based peering
b) Shut the interface the peering is over
c) remove the peering from bgp

Show that this no longer happens

Signed-off-by: Donald Sharp <sharpd@nvidia.com>

diff --git a/tests/topotests/bgp_unnumbered/__init__.py b/tests/topotests/bgp_unnumbered/__init__.py
new file mode 100644 (file)
index 0000000..e69de29

diff --git a/tests/topotests/bgp_unnumbered/r1/bgpd.conf b/tests/topotests/bgp_unnumbered/r1/bgpd.conf
new file mode 100644 (file)
index 0000000..a9d0ec8
--- /dev/null
+++ b/tests/topotests/bgp_unnumbered/r1/bgpd.conf
@@ -0,0 +1,9 @@
+!
+router bgp 65001
+  timers bgp 1 9
+  no bgp ebgp-requires-policy
+  neighbor r1-eth0 interface remote-as external
+  address-family ipv4 unicast
+  exit-address-family
+ !
+!

diff --git a/tests/topotests/bgp_unnumbered/r1/zebra.conf b/tests/topotests/bgp_unnumbered/r1/zebra.conf
new file mode 100644 (file)
index 0000000..1cbaea4
--- /dev/null
+++ b/tests/topotests/bgp_unnumbered/r1/zebra.conf
@@ -0,0 +1,10 @@
+!
+interface lo
+ ip address 172.16.250.254/32
+!
+interface r1-eth0
+ ip address 192.168.0.1/24
+!
+ip forwarding
+!
+

diff --git a/tests/topotests/bgp_unnumbered/r2/bgpd.conf b/tests/topotests/bgp_unnumbered/r2/bgpd.conf
new file mode 100644 (file)
index 0000000..fd29cd3
--- /dev/null
+++ b/tests/topotests/bgp_unnumbered/r2/bgpd.conf
@@ -0,0 +1,9 @@
+!
+router bgp 65002
+  no bgp network import-check
+  no bgp ebgp-requires-policy
+  timers bgp 1 9
+  neighbor r2-eth0 interface remote-as external
+  address-family ipv4 uni
+    network 172.16.255.254/32
+!

diff --git a/tests/topotests/bgp_unnumbered/r2/zebra.conf b/tests/topotests/bgp_unnumbered/r2/zebra.conf
new file mode 100644 (file)
index 0000000..cf6fb6d
--- /dev/null
+++ b/tests/topotests/bgp_unnumbered/r2/zebra.conf
@@ -0,0 +1,12 @@
+!
+interface r2-eth0
+ ip address 192.168.0.2/24
+!
+interface r2-eth1
+ ip address 192.168.1.1/24
+!
+interface r2-eth2
+ ip address 192.168.2.1/24
+!
+ip forwarding
+!

diff --git a/tests/topotests/bgp_unnumbered/test_bgp_unnumbered.py b/tests/topotests/bgp_unnumbered/test_bgp_unnumbered.py
new file mode 100644 (file)
index 0000000..de4c4cf
--- /dev/null
+++ b/tests/topotests/bgp_unnumbered/test_bgp_unnumbered.py
@@ -0,0 +1,132 @@
+#!/usr/bin/env python
+#
+# Copyright (c) 2022 by
+# Donald Sharp
+#
+# 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.
+#
+
+"""
+Test some bgp interface based issues that show up
+"""
+
+import os
+import sys
+import json
+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.common_config import step
+
+pytestmark = [pytest.mark.bgpd]
+
+
+def build_topo(tgen):
+
+    tgen.add_router("r1")
+    tgen.add_router("r2")
+
+    switch = tgen.add_switch("s1")
+    switch.add_link(tgen.gears["r1"])
+    switch.add_link(tgen.gears["r2"])
+
+
+def setup_module(mod):
+    tgen = Topogen(build_topo, mod.__name__)
+    tgen.start_topology()
+
+    router_list = tgen.routers()
+
+    for i, (rname, router) in enumerate(router_list.items(), 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()
+
+
+#
+# Test these events:
+# a) create an unnumbered neighbor
+# b) shutdown the interface
+# c) remove the unnumbered peer in bgp and bgp does not crash
+def test_bgp_unnumbered_removal():
+    tgen = get_topogen()
+
+    if tgen.routers_have_failure():
+        pytest.skip(tgen.errors)
+
+    def _bgp_nexthop_cache():
+        output = tgen.gears["r1"].vtysh_cmd("show bgp nexthop")
+        expected = "Current BGP nexthop cache:\n"
+        return output == expected
+
+    def _bgp_converge():
+        output = json.loads(
+            tgen.gears["r1"].vtysh_cmd("show ip bgp 172.16.255.254/32 json")
+        )
+        expected = {"prefix": "172.16.255.254/32"}
+
+        return topotest.json_cmp(output, expected)
+
+    step("Ensure Convergence of BGP")
+    test_func = functools.partial(_bgp_converge)
+    success, result = topotest.run_and_expect(test_func, None, count=60, wait=1)
+
+    assert result is None, 'Failed bgp convergence in "{}"'.format(tgen.gears["r2"])
+
+    step("Shutdown interface r1-eth0")
+
+    tgen.gears["r1"].vtysh_cmd(
+        """
+           configure
+           int r1-eth0
+             shutdown
+        """
+    )
+
+    step("Remove the neighbor from r1")
+    tgen.gears["r1"].vtysh_cmd(
+        """
+           configure
+           router bgp
+            no neighbor r1-eth0 interface remote-as external
+       """
+    )
+
+    step("Ensure that BGP does not crash")
+    test_func = functools.partial(_bgp_nexthop_cache)
+    success, result = topotest.run_and_expect(test_func, True, count=10, wait=1)
+
+    assert result is True, "BGP did not crash on r1"
+
+
+if __name__ == "__main__":
+    args = ["-s"] + sys.argv[1:]
+    sys.exit(pytest.main(args))