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Can you decode custom UDP packets?


I have a Xilinx board pushing out periodic UDP messages to the network with a computer running WireShark that is picking up all of the messages that the FPGA is generating. The data section of the UDP packet is not simple to decode so troubleshooting while just looking at the HEX ins't a very easy task. Is it possible to create my own decoder so that custom fields can be populated with human readable text?

If the above answer is yes then how do I create one of those decoders and where do I put it in the Wireshark directory structure?

Thank you.

Details: Computer: standard Windows XP 32bit

asked 08 Mar '13, 11:11

madscientist314's gravatar image

accept rate: 0%

One Answer:


There are three main ways to create a dissector; a text based one with WSGD, a script based one in lua or python, or a c dissector.

WSGD is a DLL that adds dissection via a text based description. Relatively simple to start with and for simple protocols may be sufficient. Windows only.

Wireshark supports Lua and Python as scripting languages for creating dissectors, lua is the most popular. Lua is available on more platforms than python.

A c based dissector is the traditional way to write a dissector, facilities are very comprehensive but it can be the most complicated method.

answered 08 Mar '13, 13:19

grahamb's gravatar image

grahamb ♦
accept rate: 22%