Subject: Re: independant setting of ifp/ifa on routes
To: Bill Sommerfeld <sommerfeld@orchard.arlington.ma.us>
From: Christian E. Hopps <chopps@merit.edu>
List: tech-net
Date: 06/25/1999 11:58:20
> gated:
> 	gated appears to set RTA_IFP in some of the multicast routing
> 	code for an RTM_CHANGE message (in krt_resolve_cache in
> 	krt_ipmulti_rtsock.c); my change is only to  how RTA_IFP/RTA_IFA
> 	are handled in an RTM_ADD message.

I don't believe the krt_ipmulti_rtsock.c code is used currently, which
is the only reference to this that I found.

> 	like routed, gated doesn't set RTA_IFP or RTA_IFA in the
> 	unicast routing code.

I'd like to use this though.  GateD currenlty uses the gateway router
(next hop) internally to determine which interface the route is attached
to.  I believe this echos whats done in the kernel.

If I understand you change I can now specifically state which interface
the route should be bound to regardless of the gateway.  Clearly
for RTA_IFP sockaddr_dl is the right way to go.  If you can make
this change it would please me greatly. :)

> Naturally, some additional work in the kernel and in gated would allow
> for true unnumbered point-to-point interfaces.

This would be very nice.  I'm guessing that the work involves removing
the need for a gateway to be specified, as long as the interface is
given.

Chris.