source-address selection and RTF_SRC

[David Young <dyoung%pobox.com@localhost>]

I've started to work again on source address-selection policies.  See
<http://mail-index.netbsd.org/tech-net/2006/09/02/0000.html> for the
work that I did previously.

Currently, IPSELSRC overrides source addresses set with the routing
socket.  That is, if I set a source address with "route add <dst> <gw>
-ifa <src>", and I have 'options IPSELSRC' in my kernel configuration,
then IPSELSRC policy overrides <src>.  That's probably not what the
operator intends.

To stop policy from overriding the source address set on a route, I
propose to add a flag RTF_SRC.  If a routing socket client supplies a
route's interface address, then the kernel sets RTF_SRC on the route.
When RTF_SRC is set on a route, the kernel does not use applicable
IPSELSRC policies, but uses rt_ifa, instead.

Ok?

Dave

-- 
David Young             OJC Technologies
dyoung%ojctech.com@localhost      Urbana, IL * (217) 344-0444 x24