Ethereal-dev: Re: [Ethereal-dev] OSPFv3 checksum calculation

Note: This archive is from the project's previous web site, ethereal.com. This list is no longer active.

Date Index Thread Index Other Months All Mailing Lists
Date Prev Date Next Thread Prev Thread Next
From: Guy Harris <gharris@xxxxxxxxx>
Date: Tue, 27 Nov 2001 22:46:45 -0800
On Wed, Nov 28, 2001 at 11:26:35AM +0900, Taisuke Sasaki wrote:
> Though Ethereal-0.8.20 supports an OSPFv3 dissector,
> it seems that OSPFv3 header checksum calculation is something wrong.
> 
> rfc2470 says that a "pseudo-header" of IPv6 header fields
> is used in OSPFv3 checksum calculation,
> but I cannot find the corresponding source code in latest
> CVS repository(packet-ospf.c).
> 
> below is a temporary patch in OSPFv3 header checksum calculation.

I've checked in a modified version - if the version is neither
OSPF_VERSION_2 nor OSPF_VERSION_3, it doesn't compute the checksum at
all, and instead of constructing the entire pseudo-header it uses the
scatter/gather capabilities of "in_cksum()" (similar to what the TCP
dissector does).

> (I have compiled, but never tested).

I don't have any OSPFv3 captures, so I haven't tested it, either.