Subject: Re: multicast routing over vifs broken?
To: None <>
From: Christos Zoulas <>
List: tech-net
Date: 07/26/2005 21:18:55
In article <>,
Greg Troxel  <> wrote:
>My group has been setting up dynamic tunnels in mrouted over wireless
>interfaces, and found what looks like a bug in
>The protocol is checked against AF_INET (2), when it seems like it
>should be checked against ENCAP_PROTO (IPPROTO_IPIP, which is 4).
>As a result incoming packets on vifs are dropped.
>	if (!vifp || proto != AF_INET) {
>		m_freem(m);
>		mrtstat.mrts_bad_tunnel++;
>		return;
>	}
>This code was last touched on 08-May-01 in revision 1.54, which
>changed to use the new encap matching framework.
>Christine Jones of BBN found this, and when changed to ENCAP_PROTO
>packets are received on vifs.
>The code seems "clearly wrong by inspection", but given that it's been
>4 years I wonder if we're somehow confused.  Has mrouted with vifs
>worked for anyone since May 2001?  Should I just change AF_INET to

Yes you should :-)