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Re: Lua dissector for raw 802.11 data frames
From: "Kanstrup, Mikael" <Mikael.Kanstrup () sony com>
Date: Tue, 22 May 2018 12:59:59 +0000
?> I am working on a dissector that dissects a proprietary protocol that uses raw 802.11 data frames. The protocol > specification is not open so I won't be able to contribute the dissector. I've therefore chosen to implement it in Lua.
Without patching Wireshark's 802.11 dissector I'm not able to register my own dissector. So seeking advice on properways to proceed and implement.
I can get it working by adding support for heuristic sub-dissectors on 802.11 data frames. An unfinished example > uploaded here:
https://code.wireshark.org/review/#/c/27641/?
I've uploaded an updated version of that patch that now only hand-offs the data portion of the frame. This together with me realizing that frame header fields can be accessed via Fields.new(...) solves the original problems I faced. With the patch above applied I can register a (Lua) heuristics dissector for raw 802.11 data frames. Updated Lua sample dissector below: local proto_example = Proto("example", "example protocol") local wlan_ra_f = Field.new("wlan.ra") local f = proto_example.fields function is_example_protocol(tvb, pinfo) -- check frame and decide whether example protocol -- if access to 802.11 frame header fields is needed these can -- be retrieved via: local wlan_ra = wlan_ra_f() -- ... return true end function proto_example.dissector(tvb, pinfo, tree) if not is_example_protocol(tvb) then return 0 end pinfo.cols.info = "" pinfo.cols.protocol = "Example" tree = tree:add(proto_example, tvb) tree:add(f.data, tvb(0)); return tvb:len() end proto_example:register_heuristic("wlan_data", proto_example.dissector) f.data = ProtoField.bytes("example.data", "data") /Mikael ___________________________________________________________________________ Sent via: Wireshark-dev mailing list <wireshark-dev () wireshark org> Archives: https://www.wireshark.org/lists/wireshark-dev Unsubscribe: https://www.wireshark.org/mailman/options/wireshark-dev mailto:wireshark-dev-request () wireshark org?subject=unsubscribe
Current thread:
- Lua dissector for raw 802.11 data frames Kanstrup, Mikael (May 18)
- Re: Lua dissector for raw 802.11 data frames Kanstrup, Mikael (May 22)