Ethereal-dev: Re: [Ethereal-dev] [PATCH] Q.931 fails to pass long message to H.225

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From: Jaap Keuter <jaap.keuter@xxxxxxxxx>
Date: Tue, 22 Nov 2005 12:16:29 +0100 (CET)
On Tue, 22 Nov 2005, Ulf Lamping wrote:

> Anders Broman (AL/EAB) wrote:
>
> >Hi,
> >Should the TCP dissector realy supress desegmentation if the checksum is
> >faulty?
> >
>
> I was asking myself the same question before ...
>
> IMHO it should try to desegment even if the checksum is invalid.
>
> I ended up disabling the checksum check for that reason, as a lot of
> captures I get seems to use checksum offloading (overloading?).

It seems that inhibiting desegmentation i.c.o. TCP checksum error is
rather old (svn blame says guy, revision 4571). My guess is that Ethereal
used to break badly when out-of-bound operations were performed, which a
TCP checksum error may predict. Nowadays we have nice exception handling,
so IMHO this preventive measure may be relaxed.

just my $0.02
Jaap