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 <rzalamena@opensourcerouting.org>
This commit is contained in:
Rafael Zalamena 2018-11-03 19:08:33 -03:00
parent d0ca6a3406
commit de61f256d6

View file

@ -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);
}
}