netdev - Re: UDP checksum broken since 2.6.18?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 23 May 2007 10:33:16 +0000
From:	"Thomas B. Rücker" <dm8tbr@...npma.org>
To:	Herbert Xu <herbert@...dor.apana.org.au>
CC:	shemminger@...ux-foundation.org, pg@...ureware.at,
	netdev@...r.kernel.org
Subject: Re: UDP checksum broken since 2.6.18?

Herbert Xu wrote:
> "Thomas B. R??cker" <dm8tbr@...npma.org> wrote:
>   
>> Stephen Hemminger wrote:
>>     
>>> The packet passed to packet capture programs may not have a valid checksum
>>> if you have checksum offload configured on the device.  What kind of hardware
>>> do you have on sender and receiver? 
>>>       
>> The c-snippet uses 127.x.x.x --> loopback
>>     
>
> We never compute the complete checksum for loopback so that explains
> the bogus checksum.
>   
Does this also explain why wireshark thinks the checksum is right when
tested on <=2.6.17?

Cheers

Thomas
-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html