diff --git a/bgpd/bgp_packet.c b/bgpd/bgp_packet.c index 3ede2ce9fb..7137c1a784 100644 --- a/bgpd/bgp_packet.c +++ b/bgpd/bgp_packet.c @@ -974,14 +974,21 @@ static int bgp_collision_detect(struct peer *new, struct in_addr remote_id) return -1; } else if ((peer->status == OpenConfirm) || (peer->status == OpenSent)) { - /* 1. The BGP Identifier of the local system is compared - to - the BGP Identifier of the remote system (as specified - in - the OPEN message). */ - + /* 1. The BGP Identifier of the local system is + * compared to the BGP Identifier of the remote + * system (as specified in the OPEN message). + * + * If the BGP Identifiers of the peers + * involved in the connection collision + * are identical, then the connection + * initiated by the BGP speaker with the + * larger AS number is preserved. + */ if (ntohl(peer->local_id.s_addr) - < ntohl(remote_id.s_addr)) + < ntohl(remote_id.s_addr) + || (ntohl(peer->local_id.s_addr) + == ntohl(remote_id.s_addr) + && peer->local_as < peer->as)) if (!CHECK_FLAG(peer->sflags, PEER_STATUS_ACCEPT_PEER)) { /* 2. If the value of the local BGP @@ -1005,10 +1012,13 @@ static int bgp_collision_detect(struct peer *new, struct in_addr remote_id) return -1; } else { - if (ntohl(peer->local_id.s_addr) == - ntohl(remote_id.s_addr)) - flog_err(EC_BGP_ROUTER_ID_SAME, "Peer's router-id %s is the same as ours", - inet_ntoa(remote_id)); + if (ntohl(peer->local_id.s_addr) + == ntohl(remote_id.s_addr) + && peer->local_as == peer->as) + flog_err( + EC_BGP_ROUTER_ID_SAME, + "Peer's router-id %s is the same as ours", + inet_ntoa(remote_id)); /* 3. Otherwise, the local system closes newly created @@ -1197,10 +1207,17 @@ static int bgp_open_receive(struct peer *peer, bgp_size_t size) } } - /* remote router-id check. */ + /* rfc6286: + * If the BGP Identifier field of the OPEN message + * is zero, or if it is the same as the BGP Identifier + * of the local BGP speaker and the message is from an + * internal peer, then the Error Subcode is set to + * "Bad BGP Identifier". + */ if (remote_id.s_addr == INADDR_ANY || IPV4_CLASS_DE(ntohl(remote_id.s_addr)) - || ntohl(peer->local_id.s_addr) == ntohl(remote_id.s_addr)) { + || (peer->sort == BGP_PEER_IBGP + && ntohl(peer->local_id.s_addr) == ntohl(remote_id.s_addr))) { if (bgp_debug_neighbor_events(peer)) zlog_debug("%s bad OPEN, wrong router identifier %s", peer->host, inet_ntoa(remote_id)); diff --git a/doc/user/overview.rst b/doc/user/overview.rst index c9934d1c68..cf8cc44097 100644 --- a/doc/user/overview.rst +++ b/doc/user/overview.rst @@ -300,6 +300,8 @@ BGP :t:`The Generalized TTL Security Mechanism (GTSM). V. Gill, J. Heasley, D. Meyer, P. Savola, C. Pingnataro. October 2007.` - :rfc:`5575` :t:`Dissemination of Flow Specification Rules. P. Marques, N. Sheth, R. Raszuk, B. Greene, J. Mauch, D. McPherson. August 2009` +- :rfc:`6286` + :t:`Autonomous-System-Wide Unique BGP Identifier for BGP-4. E. Chen, J. Yuan, June 2011.` - :rfc:`6608` :t:`Subcodes for BGP Finite State Machine Error. J. Dong, M. Chen, Huawei Technologies, A. Suryanarayana, Cisco Systems. May 2012.` - :rfc:`6810` diff --git a/tests/topotests/bgp_as_wide_bgp_identifier/__init__.py b/tests/topotests/bgp_as_wide_bgp_identifier/__init__.py new file mode 100644 index 0000000000..e69de29bb2 diff --git a/tests/topotests/bgp_as_wide_bgp_identifier/r1/bgpd.conf b/tests/topotests/bgp_as_wide_bgp_identifier/r1/bgpd.conf new file mode 100644 index 0000000000..fc273ba7c6 --- /dev/null +++ b/tests/topotests/bgp_as_wide_bgp_identifier/r1/bgpd.conf @@ -0,0 +1,5 @@ +! exit1 +router bgp 65001 + bgp router-id 10.10.10.10 + neighbor 192.168.255.1 remote-as 65002 +! diff --git a/tests/topotests/bgp_as_wide_bgp_identifier/r1/zebra.conf b/tests/topotests/bgp_as_wide_bgp_identifier/r1/zebra.conf new file mode 100644 index 0000000000..c060e1402e --- /dev/null +++ b/tests/topotests/bgp_as_wide_bgp_identifier/r1/zebra.conf @@ -0,0 +1,6 @@ +! exit1 +interface r1-eth0 + ip address 192.168.255.2/24 +! +ip forwarding +! diff --git a/tests/topotests/bgp_as_wide_bgp_identifier/r2/bgpd.conf b/tests/topotests/bgp_as_wide_bgp_identifier/r2/bgpd.conf new file mode 100644 index 0000000000..1134d98b38 --- /dev/null +++ b/tests/topotests/bgp_as_wide_bgp_identifier/r2/bgpd.conf @@ -0,0 +1,6 @@ +! spine +router bgp 65002 + bgp router-id 10.10.10.10 + neighbor 192.168.255.2 remote-as 65001 + neighbor 192.168.255.3 remote-as 65002 +! diff --git a/tests/topotests/bgp_as_wide_bgp_identifier/r2/zebra.conf b/tests/topotests/bgp_as_wide_bgp_identifier/r2/zebra.conf new file mode 100644 index 0000000000..a45520f97f --- /dev/null +++ b/tests/topotests/bgp_as_wide_bgp_identifier/r2/zebra.conf @@ -0,0 +1,6 @@ +! spine +interface r2-eth0 + ip address 192.168.255.1/24 +! +ip forwarding +! diff --git a/tests/topotests/bgp_as_wide_bgp_identifier/r3/bgpd.conf b/tests/topotests/bgp_as_wide_bgp_identifier/r3/bgpd.conf new file mode 100644 index 0000000000..fa943d10c3 --- /dev/null +++ b/tests/topotests/bgp_as_wide_bgp_identifier/r3/bgpd.conf @@ -0,0 +1,5 @@ +! exit2 +router bgp 65002 + bgp router-id 10.10.10.10 + neighbor 192.168.255.1 remote-as 65002 +! diff --git a/tests/topotests/bgp_as_wide_bgp_identifier/r3/zebra.conf b/tests/topotests/bgp_as_wide_bgp_identifier/r3/zebra.conf new file mode 100644 index 0000000000..2f4dbc5efd --- /dev/null +++ b/tests/topotests/bgp_as_wide_bgp_identifier/r3/zebra.conf @@ -0,0 +1,6 @@ +! exit2 +interface r3-eth0 + ip address 192.168.255.3/24 +! +ip forwarding +! diff --git a/tests/topotests/bgp_as_wide_bgp_identifier/test_bgp_as_wide_bgp_identifier.py b/tests/topotests/bgp_as_wide_bgp_identifier/test_bgp_as_wide_bgp_identifier.py new file mode 100644 index 0000000000..55021aaa09 --- /dev/null +++ b/tests/topotests/bgp_as_wide_bgp_identifier/test_bgp_as_wide_bgp_identifier.py @@ -0,0 +1,118 @@ +#!/usr/bin/env python + +# +# test_bgp_as_wide_bgp_identifier.py +# Part of NetDEF Topology Tests +# +# Copyright (c) 2020 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. +# + +""" +rfc6286: Autonomous-System-Wide Unique BGP Identifier for BGP-4 +Test if 'Bad BGP Identifier' notification is sent only to +internal peers (autonomous-system-wide). eBGP peers are not +affected and should work. +""" + +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, 4): + tgen.add_router('r{}'.format(routern)) + + switch = tgen.add_switch('s1') + switch.add_link(tgen.gears['r1']) + switch.add_link(tgen.gears['r2']) + switch.add_link(tgen.gears['r3']) + +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_as_wide_bgp_identifier(): + tgen = get_topogen() + + if tgen.routers_have_failure(): + pytest.skip(tgen.errors) + + def _bgp_converge(router): + output = json.loads(router.vtysh_cmd("show ip bgp neighbor 192.168.255.1 json")) + expected = { + '192.168.255.1': { + 'bgpState': 'Established' + } + } + return topotest.json_cmp(output, expected) + + def _bgp_failed(router): + output = json.loads(router.vtysh_cmd("show ip bgp neighbor 192.168.255.1 json")) + expected = { + '192.168.255.1': { + 'lastNotificationReason': 'OPEN Message Error/Bad BGP Identifier' + } + } + return topotest.json_cmp(output, expected) + + test_func = functools.partial(_bgp_converge, tgen.gears['r1']) + success, result = topotest.run_and_expect(test_func, None, count=60, wait=0.5) + + assert result is None, 'Failed to converge: "{}"'.format(tgen.gears['r1']) + + test_func = functools.partial(_bgp_failed, tgen.gears['r3']) + success, result = topotest.run_and_expect(test_func, None, count=60, wait=0.5) + + assert result is None, 'Bad BGP Identifier notification not sent: "{}"'.format(tgen.gears['r3']) + +if __name__ == '__main__': + args = ["-s"] + sys.argv[1:] + sys.exit(pytest.main(args))