cleanup dissector

dissector.lua

@@ -4,7 +4,7 @@ ilnk_proto = Proto("iLnkP2P", "iLnk")
 -- Define the fields you want to display in Wireshark
 ilnk_proto.fields = {}
 ilnk_proto.fields.type = ProtoField.string("iLnkP2P.type", "Type")
-ilnk_proto.fields.payload = ProtoField.bytes("iLnkP2P.payload", "Payload")
+-- ilnk_proto.fields.payload = ProtoField.bytes("iLnkP2P.payload", "Payload")
 ilnk_proto.fields.len = ProtoField.uint16("iLnkP2P.len", "Packet length", base.HEX)
 
 ilnk_proto.fields.m_type 		= ProtoField.uint8("iLnkP2P.m_type", "Stream type", base.HEX)
@@ -19,8 +19,7 @@ ilnk_proto.fields.cmd_dest 		= ProtoField.uint16("iLnkP2P.cmd_dest", "Dest", bas
 ilnk_proto.fields.auth_token 		= ProtoField.bytes("iLnkP2P.auth_token", "CMD auth token", base.DASH)
 ilnk_proto.fields.cmd_payload 		= ProtoField.bytes("iLnkP2P.payload", "CMD Payload", base.DASH)
 -- jpeg | audio | continuation type?
--- ilnk_proto.fields.cmd_payload 		= ProtoField.bytes("iLnkP2P.payload", "Payload", base.DASH)
+ilnk_proto.fields.data_payload 		= ProtoField.bytes("iLnkP2P.data_payload", "Data Payload", base.DASH)
--- ilnk_proto.fields.cmd_payload 		= ProtoField.bytes("iLnkP2P.payload", "Payload", base.DASH)
 
 ilnk_proto.fields.encrypted 		= ProtoField.bool("iLnkP2P.encrypted", "Encrypted")
 ilnk_proto.fields.cmd_type 		= ProtoField.string("iLnkP2P.cmd_type", "Cmd Pkt Type")
@@ -75,60 +74,62 @@ function ilnk_proto.dissector(buffer, pinfo, tree)
 	if packetname == "Drw" then
 		local b_pkt_len = buffer(2, 2)
 		local pkt_len = b_pkt_len:uint()
+		local is_data_packet = buffer(5, 1):uint() == 1
 		subtree:add(ilnk_proto.fields.len, b_pkt_len)
 		subtree:add(ilnk_proto.fields.m_type, buffer(4, 1))
 		subtree:add(ilnk_proto.fields.m_stream_id, buffer(5, 1))
 		subtree:add(ilnk_proto.fields.pkt_seq, buffer(6, 2))
-		subtree:add_le(ilnk_proto.fields.start, buffer(8, 2))
-		subtree:add_le(ilnk_proto.fields.cmd, buffer(0xa, 2))
 		local b_payload_len = buffer(0xc, 2)
 		local payload_len = buffer(0xc, 2):le_uint()
 
-		if buffer(0xb, 1):uint() % 2 == 1 then
+		if not is_data_packet then
-			cmdtype = "ack"
+			subtree:add_le(ilnk_proto.fields.start, buffer(8, 2))
+			subtree:add_le(ilnk_proto.fields.cmd, buffer(0xa, 2))
+			subtree:add_le(ilnk_proto.fields.cmd_payload_len, b_payload_len)
+			subtree:add_le(ilnk_proto.fields.cmd_dest, buffer(0xe, 2))
+			-- inline value for short-payload bytes
+			subtree:add(ilnk_proto.fields.auth_token, buffer(0x10, 4))
+
+			if buffer(0xb, 1):uint() % 2 == 1 then
+				cmdtype = "ack"
+			else
+				cmdtype = "cmd"
+			end
+			subtree:add(ilnk_proto.fields.cmd_type, cmdtype):set_generated()
+			subtree:add(ilnk_proto.fields.encrypted, payload_len >= 5):set_generated()
+
+			if payload_len >= 5 then
+				local payload = buffer(0x14, payload_len - 4)
+				local dec_payload = ByteArray.new()
+				dec_payload:set_size(payload_len - 4)
+				for i=4,payload_len-5 do -- inclusive upper range
+					local v = buffer(0x14 + i-4, 1):uint()
+					if (v % 2) == 0 then
+						v = v + 1
+					else
+						v = v - 1
+					end
+					dec_payload:set_index(i, v)
+				end
+				for i=0,3 do
+					local v = buffer(pkt_len+i, 1):uint()
+					if v % 2 == 0 then
+						v = v + 1
+					else
+						v = v - 1
+					end
+					dec_payload:set_index(i, v)
+				end
+				local dec_tvb = ByteArray.tvb(dec_payload, "Decrypted payload")
+				subtree:add(ilnk_proto.fields.decrypted_data, dec_tvb:range(0, payload_len -4) ):set_generated()
+
+				local payload_tvb = ByteArray.tvb(buffer(0x14, payload_len -4):bytes(), "CMD Payload")
+				subtree:add(ilnk_proto.fields.cmd_payload, payload_tvb:range(0, payload_len -4))
+			end
 		else
-			cmdtype = "cmd"
+			local payload_tvb = ByteArray.tvb(buffer(8, packet_length-8):bytes(), "Data Payload")
+			subtree:add(ilnk_proto.fields.data_payload, payload_tvb:range(0, packet_length-8))
 		end
-
-		subtree:add_le(ilnk_proto.fields.cmd_payload_len, b_payload_len)
-		subtree:add_le(ilnk_proto.fields.cmd_dest, buffer(0xe, 2))
-		-- inline value for short-payload bytes
-		subtree:add(ilnk_proto.fields.auth_token, buffer(0x10, 4))
-
-		subtree:add(ilnk_proto.fields.cmd_type, cmdtype):set_generated()
-		subtree:add(ilnk_proto.fields.encrypted, payload_len >= 5):set_generated()
-		if payload_len >= 5 then
-			local payload = buffer(0x14, payload_len - 4)
-			local dec_payload = ByteArray.new()
-			dec_payload:set_size(payload_len - 4)
-			for i=4,payload_len-5 do -- inclusive upper range
-				local v = buffer(0x14 + i-4, 1):uint()
-				if (v % 2) == 0 then
-					v = v + 1
-				else
-					v = v - 1
-				end
-				dec_payload:set_index(i, v)
-			end
-			for i=0,3 do
-				local v = buffer(pkt_len+i, 1):uint()
-				if v % 2 == 0 then
-					v = v + 1
-				else
-					v = v - 1
-				end
-				dec_payload:set_index(i, v)
-			end
-			local dec_tvb = ByteArray.tvb(dec_payload, "Decrypted payload")
-			subtree:add(ilnk_proto.fields.decrypted_data, dec_tvb:range(0, payload_len -4) ):set_generated()
-
-			local payload_tvb = ByteArray.tvb(buffer(0x14, payload_len -4):bytes(), "CMD Payload")
-			subtree:add(ilnk_proto.fields.cmd_payload, payload_tvb:range(0, payload_len -4))
-		end
-
-		--
-		-- subtree:add(ilnk_proto.fields.cmd, buffer(0xc, 2))
-
 	end
 	--  AvcLIB = src/IpcSession.cpp, line 1113, CmdSndProc:BATC609531EXLVS[0:0:10] now CmdSend[start=a11,cmd=1032,len=4,dest=0]=12
     -- UDP PKT SEND Drw (0xf1d0)
@@ -136,7 +137,7 @@ function ilnk_proto.dissector(buffer, pinfo, tree)
     -- 00000000  f1 d0 00 10 d1 00 00 04 11 0a 32 10 04 00 00 00  ..........2.....
     -- 00000010  50 70 77 35                                      Ppw5
 
-	subtree:add(ilnk_proto.fields.payload, buffer(2, packet_length-2))
+	-- subtree:add(ilnk_proto.fields.payload, buffer(2, packet_length-2))
 end
 
 udp_table = DissectorTable.get("udp.port"):add(49512, ilnk_proto)