Florian Klink <[email protected]> writes:
> Hey,
>
> I spotted one of my bird installations being quite spammy with:
>
>> babel1: Socket error on <iface>: Destination address required
>
> Digging through the archives, I found this has previously already been
> reported
> in BFD contexts, in every occasion, wireguard being mentioned too:
>
> - [email protected]
> - [email protected]
> - [email protected]
>
> Now with me seeing this for babel, I took a closer look.
>
> It seems to be a generic behaviour with how wireguard links behave:
>
> If the peer the packet should be sent to is offline (or has not yet completed
> the handshake), the kernel sends a 'Destination address required' error:
>
> ```
> root@flint2:~# ping fe80::5%wg_rock
> PING fe80::5%wg_rock (fe80::5%13): 56 data bytes
> ping: sendto: Destination address required
> ```
>
> ```
> root@flint2:~# wg show wg_rock
> interface: wg_rock
> public key: YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY=
> private key: (hidden)
> listening port: 8447
>
> peer: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX=
> preshared key: (hidden)
> allowed ips: 0.0.0.0/0, ::/0
> ```
>
> This probably should get filtered out by babel if the interface is of
> wireguard
> type?
Hmm, yeah, I think we could just ignore that particular error message in
all cases. The only way it appears on a regular UDP socket is if the
application sends a message without a destination address, which we
should never do.
> Or in the babel case, such a message be considered as another signal that the
> link is down, similar to `check link yes;`?
The problem with this is that there's no signal that the link comes back
up, so it's probably better to just ignore the error and keep going...
So probably just something like:
diff --git i/proto/babel/packets.c w/proto/babel/packets.c
index f18956558190..a5c7d1178716 100644
--- i/proto/babel/packets.c
+++ w/proto/babel/packets.c
@@ -1701,8 +1701,15 @@ babel_err_hook(sock *sk, int err)
struct babel_iface *ifa = sk->data;
struct babel_proto *p = ifa->proto;
- log(L_ERR "%s: Socket error on %s: %M", p->p.name, ifa->iface->name, err);
- /* FIXME: Drop queued TLVs here? */
+ switch (err)
+ {
+ case EDESTADDRREQ:
+ DBG("%s: Ignoring socket error on %s: %M", p->p.name, ifa->iface->name,
err);
+ break;
+ default:
+ log(L_ERR "%s: Socket error on %s: %M", p->p.name, ifa->iface->name, err);
+ break;
+ }
}
-Toke
