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Wireshark-dev: Re: [Wireshark-dev] Decompress Data

From: Max Dmitrichenko <dmitrmax@xxxxxxxxx>
Date: Fri, 7 Oct 2011 13:51:13 +0400
2011/10/7 Marcel Haas <inf462@xxxxxxxxxxx>:
> And i have the next problem. Damn wireshark kick my ass :)
>
> I have some packets witch are compress witz zlib.
> I want to uncompress them.
> I read the dev-guid about transformed data but i dont have a clue.
> I were testing some stuff but with no good result.
> Can someone help me with that ?

It is simple.
1) You have to know the size of decompressed data, e.g. in buffer_size variable.
2) Alloc the buffer of needed size for it using e.g. se_alloc, e.g.
you have pointer to alloced buffer called buffer_ptr.
3) Decompress you data into that buffer.
4) call
     child_tvb = tvb_new_child_real_data(current_tvb, buffer_ptr,
buffer_size, buffer_size);
5) call
     add_new_data_source(pinfo, child_tvb, "Decompressed Data");
6*) Optionally you can dissect child_tvb as any usual TVB.

In the GUI you'll get the decompressed data into another tab called
"Decompressed Data" or any other name you provide in step 5.

--
  Max