From 0775362306d51ceb3ca847f3aacd9b0b8451465b Mon Sep 17 00:00:00 2001 From: Donatas Abraitis Date: Thu, 20 Oct 2022 11:21:51 +0300 Subject: [PATCH] bgpd: Notify BGP conditional advertisement thread when the peer goes down Also, make sure we check if the advertisement table changed using FROM peer, not TO peer. Signed-off-by: Donatas Abraitis --- bgpd/bgp_conditional_adv.c | 19 ++- bgpd/bgp_fsm.c | 3 + .../__init__.py | 0 .../r1/bgpd.conf | 17 ++ .../r1/zebra.conf | 6 + .../r2/bgpd.conf | 28 ++++ .../r2/staticd.conf | 3 + .../r2/zebra.conf | 9 + .../r3/bgpd.conf | 10 ++ .../r3/zebra.conf | 9 + ...gp_conditional_advertisement_track_peer.py | 154 ++++++++++++++++++ 11 files changed, 256 insertions(+), 2 deletions(-) create mode 100644 tests/topotests/bgp_conditional_advertisement_track_peer/__init__.py create mode 100644 tests/topotests/bgp_conditional_advertisement_track_peer/r1/bgpd.conf create mode 100644 tests/topotests/bgp_conditional_advertisement_track_peer/r1/zebra.conf create mode 100644 tests/topotests/bgp_conditional_advertisement_track_peer/r2/bgpd.conf create mode 100644 tests/topotests/bgp_conditional_advertisement_track_peer/r2/staticd.conf create mode 100644 tests/topotests/bgp_conditional_advertisement_track_peer/r2/zebra.conf create mode 100644 tests/topotests/bgp_conditional_advertisement_track_peer/r3/bgpd.conf create mode 100644 tests/topotests/bgp_conditional_advertisement_track_peer/r3/zebra.conf create mode 100644 tests/topotests/bgp_conditional_advertisement_track_peer/test_bgp_conditional_advertisement_track_peer.py diff --git a/bgpd/bgp_conditional_adv.c b/bgpd/bgp_conditional_adv.c index 2598361ad2..4ad00ed121 100644 --- a/bgpd/bgp_conditional_adv.c +++ b/bgpd/bgp_conditional_adv.c @@ -176,6 +176,7 @@ static void bgp_conditional_adv_timer(struct thread *t) struct listnode *node, *nnode = NULL; struct update_subgroup *subgrp = NULL; route_map_result_t ret; + bool advmap_table_changed = false; bgp = THREAD_ARG(t); assert(bgp); @@ -183,6 +184,20 @@ static void bgp_conditional_adv_timer(struct thread *t) thread_add_timer(bm->master, bgp_conditional_adv_timer, bgp, bgp->condition_check_period, &bgp->t_condition_check); + /* loop through each peer and check if we have peers with + * advmap_table_change attribute set, to make sure we send + * conditional advertisements properly below. + * peer->advmap_table_change is added on incoming BGP UPDATES, + * but here it's used for outgoing UPDATES, hence we need to + * check if at least one peer got advmap_table_change. + */ + for (ALL_LIST_ELEMENTS_RO(bgp->peer, node, peer)) { + if (peer->advmap_table_change) { + advmap_table_changed = true; + break; + } + } + /* loop through each peer and advertise or withdraw routes if * advertise-map is configured and prefix(es) in condition-map * does exist(exist-map)/not exist(non-exist-map) in BGP table @@ -217,8 +232,8 @@ static void bgp_conditional_adv_timer(struct thread *t) || !filter->advmap.amap || !filter->advmap.cmap) continue; - if (!peer->advmap_config_change[afi][safi] - && !peer->advmap_table_change) + if (!peer->advmap_config_change[afi][safi] && + !advmap_table_changed) continue; if (BGP_DEBUG(cond_adv, COND_ADV)) { diff --git a/bgpd/bgp_fsm.c b/bgpd/bgp_fsm.c index a85432a33b..5d83897a49 100644 --- a/bgpd/bgp_fsm.c +++ b/bgpd/bgp_fsm.c @@ -1387,6 +1387,9 @@ int bgp_stop(struct peer *peer) if (peer_established(peer)) { peer->dropped++; + /* Notify BGP conditional advertisement process */ + peer->advmap_table_change = true; + /* bgp log-neighbor-changes of neighbor Down */ if (CHECK_FLAG(peer->bgp->flags, BGP_FLAG_LOG_NEIGHBOR_CHANGES)) { diff --git a/tests/topotests/bgp_conditional_advertisement_track_peer/__init__.py b/tests/topotests/bgp_conditional_advertisement_track_peer/__init__.py new file mode 100644 index 0000000000..e69de29bb2 diff --git a/tests/topotests/bgp_conditional_advertisement_track_peer/r1/bgpd.conf b/tests/topotests/bgp_conditional_advertisement_track_peer/r1/bgpd.conf new file mode 100644 index 0000000000..1e98f4e491 --- /dev/null +++ b/tests/topotests/bgp_conditional_advertisement_track_peer/r1/bgpd.conf @@ -0,0 +1,17 @@ +! +router bgp 65001 + no bgp ebgp-requires-policy + neighbor 192.168.1.2 remote-as external + neighbor 192.168.1.2 timers 3 10 + address-family ipv4 unicast + neighbor 192.168.1.2 route-map r2 in + exit-address-family +! +ip prefix-list p1 seq 5 permit 172.16.255.31/32 +! +route-map r2 permit 10 + match ip address prefix-list p1 + set as-path replace 65003 +route-map r2 permit 20 + set as-path replace any +! diff --git a/tests/topotests/bgp_conditional_advertisement_track_peer/r1/zebra.conf b/tests/topotests/bgp_conditional_advertisement_track_peer/r1/zebra.conf new file mode 100644 index 0000000000..acf120b200 --- /dev/null +++ b/tests/topotests/bgp_conditional_advertisement_track_peer/r1/zebra.conf @@ -0,0 +1,6 @@ +! +interface r1-eth0 + ip address 192.168.1.1/24 +! +ip forwarding +! diff --git a/tests/topotests/bgp_conditional_advertisement_track_peer/r2/bgpd.conf b/tests/topotests/bgp_conditional_advertisement_track_peer/r2/bgpd.conf new file mode 100644 index 0000000000..66c3dc53b1 --- /dev/null +++ b/tests/topotests/bgp_conditional_advertisement_track_peer/r2/bgpd.conf @@ -0,0 +1,28 @@ +! +router bgp 65002 + no bgp ebgp-requires-policy + bgp conditional-advertisement timer 5 + neighbor 192.168.1.1 remote-as external + neighbor 192.168.1.1 timers 3 10 + neighbor 192.168.2.1 remote-as external + neighbor 192.168.2.1 timers 3 10 + address-family ipv4 unicast + redistribute static + neighbor 192.168.1.1 advertise-map advertise exist-map exist + neighbor 192.168.1.1 route-map deny-all out + neighbor 192.168.2.1 route-map exist in + exit-address-family +! +ip prefix-list exist seq 5 permit 172.16.255.3/32 +ip prefix-list advertise seq 5 permit 172.16.255.2/32 +! +route-map advertise permit 10 + match ip address prefix-list advertise +exit +! +route-map exist permit 10 + match ip address prefix-list exist +exit +! +route-map deny-all deny 10 +exit diff --git a/tests/topotests/bgp_conditional_advertisement_track_peer/r2/staticd.conf b/tests/topotests/bgp_conditional_advertisement_track_peer/r2/staticd.conf new file mode 100644 index 0000000000..6c013e275f --- /dev/null +++ b/tests/topotests/bgp_conditional_advertisement_track_peer/r2/staticd.conf @@ -0,0 +1,3 @@ +! +ip route 172.16.255.2/32 r2-eth1 +! diff --git a/tests/topotests/bgp_conditional_advertisement_track_peer/r2/zebra.conf b/tests/topotests/bgp_conditional_advertisement_track_peer/r2/zebra.conf new file mode 100644 index 0000000000..f229954341 --- /dev/null +++ b/tests/topotests/bgp_conditional_advertisement_track_peer/r2/zebra.conf @@ -0,0 +1,9 @@ +! +interface r2-eth0 + ip address 192.168.1.2/24 +! +interface r2-eth1 + ip address 192.168.2.2/24 +! +ip forwarding +! diff --git a/tests/topotests/bgp_conditional_advertisement_track_peer/r3/bgpd.conf b/tests/topotests/bgp_conditional_advertisement_track_peer/r3/bgpd.conf new file mode 100644 index 0000000000..5058d405d5 --- /dev/null +++ b/tests/topotests/bgp_conditional_advertisement_track_peer/r3/bgpd.conf @@ -0,0 +1,10 @@ +! +router bgp 65003 + no bgp ebgp-requires-policy + neighbor 192.168.2.2 remote-as external + neighbor 192.168.2.2 timers 3 10 + neighbor 192.168.2.2 shutdown + address-family ipv4 unicast + redistribute connected + exit-address-family +! diff --git a/tests/topotests/bgp_conditional_advertisement_track_peer/r3/zebra.conf b/tests/topotests/bgp_conditional_advertisement_track_peer/r3/zebra.conf new file mode 100644 index 0000000000..268163e0e1 --- /dev/null +++ b/tests/topotests/bgp_conditional_advertisement_track_peer/r3/zebra.conf @@ -0,0 +1,9 @@ +! +int lo + ip address 172.16.255.3/32 +! +interface r3-eth0 + ip address 192.168.2.1/24 +! +ip forwarding +! diff --git a/tests/topotests/bgp_conditional_advertisement_track_peer/test_bgp_conditional_advertisement_track_peer.py b/tests/topotests/bgp_conditional_advertisement_track_peer/test_bgp_conditional_advertisement_track_peer.py new file mode 100644 index 0000000000..591bac1682 --- /dev/null +++ b/tests/topotests/bgp_conditional_advertisement_track_peer/test_bgp_conditional_advertisement_track_peer.py @@ -0,0 +1,154 @@ +#!/usr/bin/env python + +# +# Copyright (c) 2022 by +# Donatas Abraitis +# +# 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. +# + +""" +Conditionally advertise 172.16.255.2/32 to r1, only if 172.16.255.3/32 +is received from r3. + +Also, withdraw if 172.16.255.3/32 disappears. +""" + +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): + for routern in range(1, 5): + tgen.add_router("r{}".format(routern)) + + switch = tgen.add_switch("s1") + switch.add_link(tgen.gears["r1"]) + switch.add_link(tgen.gears["r2"]) + + switch = tgen.add_switch("s2") + switch.add_link(tgen.gears["r2"]) + switch.add_link(tgen.gears["r3"]) + + +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_STATIC, os.path.join(CWD, "{}/staticd.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_conditional_advertisement_track_peer(): + tgen = get_topogen() + + r1 = tgen.gears["r1"] + r2 = tgen.gears["r2"] + r3 = tgen.gears["r3"] + + if tgen.routers_have_failure(): + pytest.skip(tgen.errors) + + def _bgp_converge(): + output = json.loads( + r2.vtysh_cmd( + "show bgp ipv4 unicast neighbors 192.168.1.1 advertised-routes json" + ) + ) + expected = { + "advertisedRoutes": {"172.16.255.2/32": None}, + "totalPrefixCounter": 0, + "filteredPrefixCounter": 0, + } + return topotest.json_cmp(output, expected) + + # Verify if R2 does not send any routes to R1 + test_func = functools.partial(_bgp_converge) + _, result = topotest.run_and_expect(test_func, None, count=30, wait=0.5) + assert result is None, "R2 SHOULD not send any routes to R1" + + step("Enable session between R2 and R3") + r3.vtysh_cmd( + """ + configure terminal + router bgp + no neighbor 192.168.2.2 shutdown + """ + ) + + def _bgp_check_conditional_static_routes_from_r2(): + output = json.loads(r1.vtysh_cmd("show bgp ipv4 unicast json")) + expected = { + "routes": { + "172.16.255.2/32": [{"valid": True, "nexthops": [{"hostname": "r2"}]}] + } + } + return topotest.json_cmp(output, expected) + + # Verify if R1 received 172.16.255.2/32 from R2 + test_func = functools.partial(_bgp_check_conditional_static_routes_from_r2) + _, result = topotest.run_and_expect(test_func, None, count=30, wait=0.5) + assert result is None, "R1 SHOULD receive 172.16.255.2/32 from R2" + + step("Disable session between R2 and R3 again") + r3.vtysh_cmd( + """ + configure terminal + router bgp + neighbor 192.168.2.2 shutdown + """ + ) + + # Verify if R2 is not sending any routes to R1 again + test_func = functools.partial(_bgp_converge) + _, result = topotest.run_and_expect(test_func, None, count=30, wait=0.5) + assert result is None, "R2 SHOULD not send any routes to R1" + + +if __name__ == "__main__": + args = ["-s"] + sys.argv[1:] + sys.exit(pytest.main(args)) -- 2.39.5