On Sep 11, 2007, at 11:39 AM, Toralf Förster wrote:
Running a stable Gentoo kernel 2.6.22-gentoo-r5 now for a while
there's only
one thing left related to this topic.
I'm wondering why some UDP packets of the MS messenger protocol
(with the usual
text like "please click at www.we-destroy-your-computer.com") always
have wrong
check sums regardless whether sniffed at ppp0 or eth0 interface.
But from all UDP packets of this (today) useless protocol only those
have wrong
check sums which are marked as "[Long frame (2 bytes)]" within
wireshark.
...
BTW the checksum is 0x0000.
If by "wrong checksum" you mean wrong UDP checksum, then, when running
over IPv4, the UDP checksum is optional - if a UDP packet has no
checksum, the checksum field has the value 0x0000, and the receiving
UDP implementation should not check the checksum.
That's probably independent of the "Long frame" issue; we'd have to
see a capture file with one of those packets to see what's causing
that issue.
