From de61f256d68bc792a3823193fa8a49fdcaf77d3c Mon Sep 17 00:00:00 2001 From: Rafael Zalamena Date: Sat, 3 Nov 2018 19:08:33 -0300 Subject: [PATCH] bfdd: fix BGP unnumbered peer setup The session key uses the scope id to figure out which interface we are using with that link-local address, so if we don't set it when registering a session we'll end up with multiple IPv6 sessions. This bug was spotted by Sandro Bolliger. Signed-off-by: Rafael Zalamena --- bfdd/ptm_adapter.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/bfdd/ptm_adapter.c b/bfdd/ptm_adapter.c index 4287891621..6e9068ae9a 100644 --- a/bfdd/ptm_adapter.c +++ b/bfdd/ptm_adapter.c @@ -381,6 +381,21 @@ static int _ptm_msg_read(struct stream *msg, int command, if (bpc->bpc_has_localif) { STREAM_GET(bpc->bpc_localif, msg, ifnamelen); bpc->bpc_localif[ifnamelen] = 0; + + /* + * IPv6 link-local addresses must use scope id, + * otherwise the session lookup will always fail + * and we'll have multiple sessions showing up. + * + * This problem only happens with single hop + * since it is not possible to have link-local + * address for multi hop sessions. + */ + if (bpc->bpc_ipv4 == false + && IN6_IS_ADDR_LINKLOCAL( + &bpc->bpc_peer.sa_sin6.sin6_addr)) + bpc->bpc_peer.sa_sin6.sin6_scope_id = + ptm_bfd_fetch_ifindex(bpc->bpc_localif); } } -- 2.39.5