While debugging some problems we were having with TCP performance, I wanted a way to visualize the MQTT traffic stream a little better in wireshark. I found Wireshark Generic Dissector and thought it should be useful, seeing as I had no desire to start writing C code for packet decoding. WSGD looks to be pretty interesting for writing decoders for private protocols and the like, but there aren’t many other examples of how it’s used. I got helpful prompt help from the lead developer though, so even though it’s a little arcane, it’s still something I can recommend :)
MQTT decoding in Wireshark through WSGD
My decoding isn’t complete, by any means, but given the complete lack of any other examples out there, I thought this would probably be helpful, even in it’s current state. You’ll need to install WSGD as per the instructions at that site, and then you’ll need this zip….
Just follow the instructions here and by all means, let me know how you go :)
Update: 2014-02-01: There’s an alternative lua plugin, available on github. I haven’t tried it, but lua plugins are actually easier to use and extend. If I’d know about the lua plugin style (and known lua) at the time, I would have done it that way. Note, I haven’t actually _tried_ the lua plugin yet :)