Ethereal-users: Re: [ethereal-users] UDP/ICMP Checksums

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From: Guy Harris <gharris@xxxxxxxxxxxx>
Date: Wed, 13 Dec 2000 01:52:47 -0800
On Thu, Sep 14, 2000 at 11:18:57AM -0700, Guy Harris wrote:
> On Thu, Sep 14, 2000 at 06:24:26PM +0200, Markus Schaber wrote:
> > Now I noticed that it correctly shows the checksum-headers for IP, UDP
> > and ICMP, but it seems that it only checks the IP checksum for
> > correctnes, and doesn't check the correctnes of the UDP and ICMP
> > checksum (I couldn't test TCP so far).
> > 
> > Now I would like to know whether I got this correct,
> 
> You are correct that the only checksum it checks is the IP header
> checksum.
> 
> > and how easy it is to add this.
> 
> I have code to do it, but it's not finished; I need to make it *not*
> check the checksum if the IP datagram containing the ICMP datagram/UDP
> datagram/TCP segment is fragmented (we don't yet reassemble fragmented
> IP datagrams, so we can't yet compute the checksum on the payload of a
> fragmented IP datagram).

Done.  It's been checked in.