Re: TCP dissect issue when app-level message spans multiple TCP packets

[Graham Bloice <graham.bloice () trihedral com>]

On 05/05/2011 16:27, Chris Maynard wrote:
> Graham Bloice <graham.bloice@...> writes:
>
> >     The
> >         get_message_tcpmessage_len function should also check that there
> >         are enough bytes in the passed in tvb to call tvb_get_letohl(),
> >         as the OP's code did.-- 
> I don't think that's the case as tcp_dissect_pdus() is told how many bytes are
> needed via the fixed_len argument, so it won't call get_message_tcpmessage_len()
> until at least that many bytes are available.
>
> See packet-tcp.c's tcp_dissect_pdus() where it checks for "if (length_remaining
> < fixed_len)".
I knew I should have looked at the code and not spouted forth from memory,
Chris is right.  I was thinking of some similar code that does some heuristic
checks before calling tcp_dissct_pdus().

-- 
Regards,

Graham Bloice

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