Re: ip_wccp.c for WCCP v2 question

Good eye, Henrik! I just goofed up the patch...

The cleanup module got removed while I was fiddling around with things.
  Me and vi are going to have words.

Thanks for lending an extra pair of eyes. (Mine have become blinded
from looking at these patches so long.)

Henrik Nordstrom wrote:

> I am not yet familar with how Linux skb processing, but:
>
> One thing I notice is that you do not verify the size of the GRE packets
> before trying to grab the encapsulated one, so if the router sends you a
> bad WCCP packet (no encapsulated packet) then oops a negative packet
> size... Bbad WCCP packets has been seen from certain IOS versions in
> certain path configurations.
>
> and why is the module cleanup code removed?
>
> /Henrik
>
> Joe Cooper wrote:
>
>> Hi folks,
>>
>> We've got WCCP v2 working with Squid, thanks to some fast coding by
>> Kevin Wormington.
>>
>> Would someone (hopefully with more Linux kernel hacking knowledge than
>> I) take a look at this ip_wccp.c module:
>>
>> http://www.swelltech.com/pengies/joe/patches/ip_wccp.c
>>
>> It's only a couple of lines bigger than the original ip_wccp.c for v1 of
>> WCCP, where it checks for the extra 4 octets of the v2 GRE header and
>> then skips them for the decapsulation...but something is causing an oops
>> on our test box. We're not real sure exactly what is going on, but this
>> seems as likely a candidate as any, since the box doesn't crash until it
>> starts seeing WCCP traffic. Unfortunately...because Kevin's router only
>> has WCCP v2 and my router only has v1, we can't do any cross-testing.
>> And the Squid in testing has not yet been made both v2 and v1 aware (it
>> can currently do v2 just fine...but v1 is broken, I'll be fixing that
>> over the next few days).
>>
>> I'd welcome some comments from you guys, if you see anything problematic
>> in the module...
>> --
>> Joe Cooper <joe@swelltech.com>
>> Affordable Web Caching Proxy Appliances
>> http://www.swelltech.com

-- 
                                   --
                      Joe Cooper <joe@swelltech.com>
                  Affordable Web Caching Proxy Appliances
                         http://www.swelltech.com