Re: IPv6: Blackhole route support partial ?

[Hannes Frederic Sowa <hannes@stressinduktion.org>]

Hello!

On Mon, Nov 11, 2013 at 07:25:14PM +0530, Kamala R wrote:
> On adding IPv6 blackhole routes, ICMP unreachable messages are being
> sent back to source. According to the definition, packets destined to
> a blackhole address must be dropped silently.

Yes, this is a bug.

> I applied the patch submitted to the 3.7 kernel that indicates that it
> supports blackhole and prohibit routes correctly. However, the patch
> only sets the error code and route type correctly, so the show command
> displays the appropriate output.
> 
> 
> It seems to me that the input and output function pointers of the dst
> variable, which determine packet processing, need to be set to
> dst_discard. This would enable correct behaviour for blackhole routes.
> Am I on the right path here ?

I think you are. ip6_pkt_discard is not the correct input/output
function for blackhole routes. In ip6_route_add simply set up the
function pointers in the switch instead to just initializing them to
ip6_pkt_discard. dst_discard is fine. Looks like prohibit rules are not
handled correctly either. They should go to ip6_pkt_prohibit. (Just look at
how the templates are initialized.)

Could you cook a patch?

Thanks,

  Hannes