Re: Wrong tcp sequence numbers???

[Guy Harris <guy () alum mit edu>]

Claudio Lavecchia wrote:

> > 3. How do you calculate size_ip?
>
> int size_ip = sizeof(struct sniff_ip);

Do any of the packets have IP options?  If so, then that's *not* the 
size of the IP header.

You should get the IP header length from the header length/version field 
from the IP header (and should check that this field has a value >= 5, 
meaning 20 bytes, as that's the minimum IP header length).
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