From mboxrd@z Thu Jan  1 00:00:00 1970
From: "U.Mutlu" <for-gmane@mutluit.com>
Subject: Re: [libnetfilter_queue] extra data after payload
Date: Fri, 23 Sep 2011 19:02:57 +0200
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U.Mutlu wrote, On 2011-09-23 18:19:
> 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?

Correction: the extra data is in front of the payload.