From 4d39f9c61c48d033ed5c9f729bdc975b58da29e8 Mon Sep 17 00:00:00 2001 From: Klement Sekera Date: Fri, 17 Jan 2020 10:01:52 +0000 Subject: [PATCH] bfd: reset peer discriminator on timeout More RFC compliance. Ticket: VPP-1816 BFD: peer discriminator not reset on timeout Type: fix Change-Id: I68063c18097d282b3527e3fb485c1d0d1fd1b0c8 Signed-off-by: Klement Sekera --- src/vnet/bfd/bfd_main.c | 13 +++++++++++++ test/test_bfd.py | 11 +++++++++++ 2 files changed, 24 insertions(+) diff --git a/src/vnet/bfd/bfd_main.c b/src/vnet/bfd/bfd_main.c index 0cc7d72c600..ef6ada8823f 100644 --- a/src/vnet/bfd/bfd_main.c +++ b/src/vnet/bfd/bfd_main.c @@ -1054,6 +1054,19 @@ bfd_check_rx_timeout (bfd_main_t * bm, bfd_session_t * bs, u64 now, now + bm->wheel_inaccuracy) { BFD_DBG ("Rx timeout, session goes down"); + /* + * RFC 5880 6.8.1. State Variables + + * bfd.RemoteDiscr + + * The remote discriminator for this BFD session. This is the + * discriminator chosen by the remote system, and is totally opaque + * to the local system. This MUST be initialized to zero. If a + * period of a Detection Time passes without the receipt of a valid, + * authenticated BFD packet from the remote system, this variable + * MUST be set to zero. + */ + bs->remote_discr = 0; bfd_set_diag (bs, BFD_DIAG_CODE_det_time_exp); bfd_set_state (bm, bs, BFD_STATE_down, handling_wakeup); /* diff --git a/test/test_bfd.py b/test/test_bfd.py index 6dc58b933db..e78ad0c4064 100644 --- a/test/test_bfd.py +++ b/test/test_bfd.py @@ -819,6 +819,16 @@ class BFD4TestCase(VppTestCase): e = self.vapi.wait_for_event(1, "bfd_udp_session_details") verify_event(self, e, expected_state=BFDState.down) + def test_peer_discr_reset_sess_down(self): + """ peer discriminator reset after session goes down """ + bfd_session_up(self) + detection_time = self.test_session.detect_mult *\ + self.vpp_session.required_min_rx / USEC_IN_SEC + self.sleep(detection_time, "waiting for BFD session time-out") + self.test_session.my_discriminator = 0 + wait_for_bfd_packet(self, + pcap_time_min=time.time() - self.vpp_clock_offset) + def test_large_required_min_rx(self): """ large remote required min rx interval """ bfd_session_up(self) @@ -2100,6 +2110,7 @@ class BFDSHA1TestCase(VppTestCase): self.test_session.vpp_seq_number = None # now throw away any pending packets self.pg0.enable_capture() + self.test_session.my_discriminator = 0 bfd_session_up(self) -- 2.16.6