Re: TCP checksum and device driver eri0

Martin Paul <[email protected]>
Newsgroups gmane.comp.security.sun
Message-ID <[email protected]>
> During a snoop session on a 280R with solaris 9 and network interface 
> eri0, I noticed that the TCP checksum field of every outgoing packet was 
> incorrect.
> ...
> The same packet snooped on the network has the correct checksum value.
> I believe that something happens between the snoop point on the machine 
> and the network interface eri0 output.

I guess that's the same effect that's described in the ethereal FAQ at:

  http://www.ethereal.com/faq.html#q5.8
  
It's because the checksum is added to the packet by the network 
interface, and not by the TCP/IP stack.

mp.
-- 
                         Martin Paul | Systems Administrator
      Institute for Software Science | [email protected]
Liechtensteinstrasse 22, A-1090 Wien | Tel: 01 4277 38803
        http://www.par.univie.ac.at/ | Fax: 01 4277 9388
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.