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Wireshark-dev: Re: [Wireshark-dev] How to reassemble in dissector plugins if fixed len part is

From: Guy Harris <guy@xxxxxxxxxxxx>
Date: Tue, 11 Mar 2008 00:43:11 -0700
Merlin Hooze wrote:

For a disector plugin, if the fixed length part of the message is
split across tcp segments, can wireshark reassemble it?

It should be able to do so. If not, that's a bug. (That's why the size of the fixed-length part of the message is passed as an argument to tcp_dissect_pdus()).

There were, in at least some Wireshark releases, bugs that caused that not to work correctly. Try it with the latest version of Wireshark, and, if it doesn't work, file a bug on bugs.wireshark.org, preferably with a sample capture file that demonstrates the bug (just include enough packets to demonstrate the problem - you can throw all other packets away, as long as loading the resulting capture shows the problem).

Or the plugin needs to take care of it once the tcp_dissect_pdus() functin returns.
Any examples available to handle this ?

Just use tcp_dissect_pdus() - it should just handle this; you don't need to do anything special, just pass the length of the fixed-length part of the message.