Re: kernel not processing ICMP Redirects

The Cow of Destruction (cowzilla@gwbbs.northeast.net)
Sat, 2 Nov 1996 08:32:26 -0600 (CST)

I have been playing around with net/ipv4/route.c for a while to see how
linux deals with icmp redirects, and it seems to me that even legitamit
icmp redirects are ignored.. I think the problem is in the line
((gw^dev->pa_addr)&dev->pa_mask)
which (from what alan cox tells me) is used to check to see if the new
gateway is in the same subnet. I am probably wrong (because I am new to
C, I used to do everything in pascal), but it looks like we would want
this to evaluate to false (refer to source) so that the route would be
added to the tables... If it evaluates to true, the route is not added..
Like I said, I am probably wrong... if anyone can explain to me what the ^
operator does, i would appreciate it..

On 1 Nov 1996, Matthew S. Crocker wrote:

> Howdie,
>
> My linux box (actually several of them) which are running 2.0.22 &
> 2.0.23 (redhat 3.0.3) are not processing ICMP redirects from my cisco
> 2501. I get the message in the kernel log (syslog) "ICMP redirect
> from 204.97.12.1" but the routing table is not updated properly. Is
> the kernel supposed to do this (I thought it did back in 1.2.13 days).
> If the kernel is not supposed to be doing this how do I go about
> updating the route table?
>
> email Answers please.
>
> -Matt
>
> --
> -Matthew S Crocker "The mask, given time, comes
> Crocker Communications to be the face itself." -anonymous
> Internet Division Phone (413) 585-5164
> PO BOX 710 Fax (413) 587-3352
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