Hello,
On Thu, 7 Jun 2001, Andrey Savochkin wrote:
> > No, the pref src from the original skb->dst appears as source
> > in our probes which is bad in my case. Of course, the preferred
> > address to the target (after ip_route_output) is our last chance.
>
> pref_src is an attribute of output routes only.
> We get it through rt_src of skb->dst only if skb->dst is the output route.
> It was you who pointed out first that the check if it's the output route is
> mandatory!
Yes, but in my case I don't like sometimes the pref_src in
skb->dst.
> > In my case, sometimes we try to probe for the nexthop when
> > sending IP packets, so in arp_solicit we can see these shared
> > addresses in the output route in skb->dst. This is the reason
> > I'm adding symmetric flag for the output routes. The scenario is:
> >
> > 192.168.0.100: shared
> > 10.0.0.1: world client (reachable through nexthop router, i.e. not
> > direct client)
> > 192.168.0.1: our nexthop router
> >
> > The packet:
> > 10.0.0.1 -> 192.168.0.100
> >
> > Our probe:
> > who-has 192.168.0.1 tell 192.168.0.100
> > ^^^^^^^^^^^^^
> >
> > 192.168.0.100 appears as pref src in skb->dst, bad in my case, i.e.
> > if we use rt_src from skb->dst. So, we must fallback to the
> > preferred src in the route to the target (ip_route_output).
>
> We do fall back in `arp-filter-src2.patch'
> after the check if skb->dst is output route.
Yes, this patch does not like all input routes but my setup does
not like some of the output routes in skb->dst too :)
> [snip]
> > > Take a peek at
> > > ftp://ftp.sw.com.sg/pub/Linux/people/saw/kernel/v2.4/route.generic
> > > (it's against 2.4.0)
> >
> > Very good. I looked in the new version. I see that you always
> > fallback to the preferred source address to the target in arp_solicit.
> > This is good for me :) Not sure what we break, though :)
>
> It's an old code.
> The current ideas and the patch that I sent are better.
> We need to call ip_route_output sometimes.
And I want to control this too, i.e. to distinguish the output
routes in skb->dst and to change the announced IP.
> Andrey
Regards
--
Julian Anastasov <ja@xxxxxx>
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