Calling Lua Dissectors from Lua Dissector

Question

I'm dealing with two custom protocols that use the same GRE protocol type. Each protocol currently has a separate Lua dissector (I'd like to keep it this way). I'm writing a script in Lua to perform some heuristics to determine which of the custom protocols is being used, with the idea that I'll pass the packet off to the appropriate Lua dissector. I've got all of the heuristics written, but I can't quite figure how to call a dissector written in Lua from another dissector written in Lua. Do I need to create a new DissectorTable? How are the (final) two dissectors referenced (dofile in the new dissector, etc.)? Any pointers you can provide would be appreciated.

Thanks.

Answer 1

You should use Dissector.get, which looks up the registered dissector by name -- no matter where you registered it (Lua or C). Then, use Dissector:call, passing the payload to be dissected (along with the packet info and protocol tree node).

From similar question:

function proto_lap5.dissector(buf, pinfo, tree)
    if buf:len() > HEADER_LEN then
        -- create a new buffer containing only the XLES data,
        -- and pass it to the XLES dissector
        Dissector.get("xles"):call(buf(HEADER_LEN):tvb(), pinfo, tree)
    end
end