From mboxrd@z Thu Jan  1 00:00:00 1970
From: "U.Mutlu" <for-gmane@mutluit.com>
Subject: [libnetfilter_queue] extra data after payload
Date: Fri, 23 Sep 2011 18:19:32 +0200
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Hi,

when reading queue data via the recv() function
then one gets a return value much longer than the payload data,
so there are some extra data after the payload.
What kind of extra data is it?

for example:
   rv  = recv(fd, buf, sizeof(buf), 0);   // rv=84
   ...
   ret = nfq_get_payload(tb, &data);      // ret=40 (ie. ip + tcp pkt, both w/o options, and tcp w/o user data)

So, here, what are the extra 44 bytes after the tcp data?