Add Wireshark dissector to testing/ dir

Author: tstenner

testing/lsl.lua

@@ -0,0 +1,57 @@
+-- Wireshark dissector for labstreamerlayer stream discovery packets
+-- Place this file in $WIRESHARK_CONFIG_DIR/plugins/lsl.lua
+-- (C) 2020 Tristan Stenner
+do
+	local lsl_proto = Proto("lsldiscovery", "Labstreaminglayer Discovery")
+	-- source fields
+	local udp_src_f = Field.new("udp.srcport")
+	local udp_dst_f = Field.new("udp.dstport")
+	-- fields to be shown in the packet analysis pane
+	local cmd_F = ProtoField.string("lsl.cmd", "Command")
+	local dst_F = ProtoField.string("lsl.dst", "Destination")
+	local query_F = ProtoField.string("lsl.query", "QueryID", "QueryID")
+	local content_F = ProtoField.string("lsl.content", "Content", "Content")
+	local streaminfo_F = ProtoField.string("lsl.streaminfo", "Streaminfo", "Streaminfo")
+	local ansport_F = ProtoField.string('lsl.answerport', 'Answer port', 'Answer port')
+
+	lsl_proto.fields = {cmd_F, dst_F, query_F, ansport_F, streaminfo_F, content_F}
+
+	function lsl_proto.dissector(buffer, pinfo, tree)
+		if udp_dst_f().value == 16571 then
+			if buffer(0, 4):string()~='LSL:' then
+				return
+			end
+			local subtree = tree:add(lsl_proto, buffer)
+
+			local data = buffer():string()
+			local newlinepos = data:find('\r\n')
+			if newlinepos == nil then
+				return
+			end
+			subtree:add(cmd_F, buffer(0, newlinepos-1))
+			buffer = buffer(newlinepos + 1)
+			newlinepos = buffer():string():find('\r\n', newlinepos+1, true)
+			if newlinepos == nil then
+				return
+			end
+			subtree:add(content_F, buffer(0, newlinepos-1))
+			buffer = buffer(newlinepos + 1)
+			local wspos = buffer():string():find(' ')
+			subtree:add(ansport_F, buffer(0, wspos-1))
+			subtree:add(query_F, buffer(wspos))
+		elseif udp_src_f().value == 16571 then
+			local subtree = tree:add(lsl_proto, buffer)
+			subtree:add(cmd_F, 'shortinfo reply')
+
+			local data = buffer():string()
+			local newlinepos = data:find('\r\n')
+			if newlinepos == nil then
+				return
+			end
+			subtree:add(query_F, buffer(0, newlinepos-1))
+			buffer = buffer(newlinepos + 1)
+			subtree:add(streaminfo_F, buffer(newlinepos+1))
+		end
+	end
+	DissectorTable.get('udp.port'):add(16571, lsl_proto)
+end