[Bro] Artificial SYN-Packets?

Lothar Braun lothar at lobraun.de
Mon Jun 8 07:49:31 PDT 2009

Hi Vern,

Vern Paxson wrote:
> A bunch of the packets have bad TCP checksums.  This is likely the problem -
> the event engine is discarding them on that account.

Thank you for the quick reply.

All the packets have bad checksums, because I padded them with
tcprewrite and forgot to use the fix checksum option. I therefore used
bro -C to disable checksum testing when I ran my script (bro actually
would have discarded these packets without -C). So I don't think this is
the source of the problem.

To make sure, I fixed the checksums with tcprewrite (see attached pcap)
and still get the same problem.

Best regards,
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