--[[ Copyright (C) 2023 Allen Hill Portions of the following are based on code from libsigrokdecode PR that is copyright (C) 2023 Maciej Grela This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . --]] local iebusproto = Proto("iebus", "IEBus protocol") -- 12-bit IEBus network (bus) addresses. Sourced from: -- - Marcin/Soft-service -- - the ADDR_* table in GadgetNutt/AVC-LAN-Module-Builder -- - lists.py in sigrokproject/libsigrokdecode#106 by @enkiusz local known_addresses = { [0x1F1] = "XM", [0x110] = "EMV", [0x120] = "AVX", [0x128] = "1DIN TV", [0x140] = "AVN", [0x144] = "G-BOOK", [0x160] = "AUDIO H/U", [0x17C] = "MONET", [0x17D] = "TEL", [0x178] = "NAV_W_CONTROLS", [0x180] = "AUDIO_ECU", -- @enkiusz labels as Rr_TV (rear TV) [0x190] = "AUDIO_HU", [0x1A0] = "DVD_P", [0x1AC] = "CAMERA-C", [0x1B0] = "REAR_TV", [0x1B4] = "SINGLE_DIN_NAV", [0x1B8] = "DISPLAY_SW", [0x1C0] = "REAR_CTRL_SW", [0x1C2] = "EURO_GW_ECU", -- @enkiusz labels as TV_TUNER2 [0x1C4] = "RUSSIA_GW_ECU", -- @enkiusz labels as PANEL [0x1C6] = "GW_ECU", [0x1C8] = "FM_MULTI_DISPLAY", [0x1CC] = "STEERING_SW", [0x1D0] = "MULTI_CD_DECODER", [0x1D4] = "DISPLAY", [0x1D6] = "CLOCK", [0x1D8] = "FR_CONTROLLED_SW", -- @enkiusz labels as GW_TRIP (G/W for Trip) [0x1DC] = "NAV_REM_CTRL", [0x1E0] = "CD_CH_COMMANDER", [0x1E4] = "CONSOLIDATED_SW", [0x1E8] = "MD_CH_COMMANDER", [0x1EC] = "BODY_COMPUTER", [0x1F0] = "AMP_RADIO_TUNER", [0x1F2] = "XM_RADIO_TUNER", -- @enkiusz labels as SIRIUS [0x1F4] = "RSA", [0x1F6] = "RSE_M", [0x1FF] = "AUDIO_BROADCAST", [0x200] = "NAV_ECU", [0x210] = "ATIS", [0x220] = "VICS", [0x230] = "TV_TUNER", [0x240] = "HW_CD_CH", [0x250] = "HW_DVD_CH", [0x260] = "TEL_INFO_ECU", [0x280] = "CAMERA_CTRLR", [0x300] = "RADIO", [0x320] = "CASSETTE", [0x330] = "CASSETTE_NO_CH", [0x340] = "CD_P", [0x360] = "1DIN_CD_CH", [0x380] = "MD_P", [0x3A0] = "MD_CH", [0x3C0] = "DAT", [0x3E0] = "DCC", [0x3F8] = "TEL_ECU", [0x400] = "EQUALIZER", [0x440] = "DSP", [0x480] = "HW_AMP", [0x500] = "GPS_RECEIVER", [0x510] = "ATIS_DECODER", [0x520] = "FM_MULTI_DECODER", [0x528] = "RADIO_WAVE_BEACON", [0x52C] = "OPTICAL_BEACON", [0x530] = "ETC", [0x540] = "CD_CH", [0x560] = "MD_CH_2", [0x580] = "CDROM_CH", [0x5A0] = "MDROM_CH", [0x5C0] = "TEL_INFO", [0x5C8] = "MAYDAY", [0x600] = "AC_ECU", [0x680] = "BODY_ECU", [0xD19] = "TURN_SIGNAL", [0xFFF] = "BROADCAST", } local f_unicast = ProtoField.bool("iebus.unicast", "Unicast", base.NONE, { [1] = "true", [2] = "false" }) local f_controller_addr = ProtoField.uint16("iebus.controller", "Controller address", base.HEX, known_addresses, 0x0FFF) local f_peripheral_addr = ProtoField.uint16("iebus.peripheral", "Peripheral address", base.HEX, known_addresses, 0x0FFF) local f_control = ProtoField.uint8("iebus.control", "Control field", base.HEX) local f_length = ProtoField.uint8("iebus.length", "Data length", base.DEC) local f_data = ProtoField.bytes("iebus.data", "Frame data", base.SPACE) iebusproto.fields = { f_unicast, f_controller_addr, f_peripheral_addr, f_control, f_length, f_data } local controlbits = { [0x0] = "READ PERIPH STATUS (SSR)", [0x1] = "UNDEFINED", [0x2] = "UNDEFINED", [0x3] = "READ & LOCK DATA", [0x4] = "READ LOCK ADDR (lo8)", [0x5] = "READ LOCK ADDR (hi4)", [0x6] = "READ & UNLOCK PERIPH STATUS (SSR)", [0x7] = "READ DATA", [0x8] = "UNDEFINED", [0x9] = "UNDEFINED", [0xA] = "WRITE & LOCK CMD", [0xB] = "WRITE & LOCK DATA", [0xC] = "UNDEFINED", [0xD] = "UNDEFINED", [0xE] = "WRITE CMD", [0xF] = "WRITE DATA" } local periphstatusbits = { [0] = "TX BUFFER EMPTY", [1] = "RX BUFFER EMPTY", [2] = "UNIT LOCKED", [4] = "TX ENABLED", [6] = "IEBUS MODE 1", [7] = "IEBUS MODE 2", } -- Expert info for unknown packet types, set as group PI_UNDECODED, severity PI_NOTE or PI_WARN -- Expert info for LAN Check [0x3, SW_ID, 0x01, 0x20] as severity PI_CHAT function iebusproto.dissector(buffer, pinfo, tree) length = buffer:len() if length == 0 then return end pinfo.cols.protocol = iebusproto.name local subtree = tree:add(iebusproto, buffer(), "IEBus frame") subtree:add(f_unicast, buffer(0,1)) subtree:add(f_controller_addr, buffer(1,2)) subtree:add(f_peripheral_addr, buffer(3,2)) pinfo.cols.src = buffer(1,2):bytes():tohex():sub(2,-1) pinfo.cols.dst = buffer(3,2):bytes():tohex():sub(2,-1) local control_item, control = subtree:add_packet_field(f_control, buffer(5,1), ENC_LITTLE_ENDIAN) -- print("control val" .. control) control_item:append_text(" (" .. controlbits[buffer(5,1):uint()] .. ")") local _, datalen = subtree:add_packet_field(f_length, buffer(6,1), ENC_LITTLE_ENDIAN) local data = subtree:add(iebusproto, buffer(), "IEBus message") data:add(f_data, buffer(7, datalen)) end local udlt = DissectorTable.get("wtap_encap") udlt:add(wtap.USER15, iebusproto) local avclanproto = Proto("avclan", "AVCLAN protocol") -- Build a reverse {value = key} lookup from a {key = value} table. Lets us keep -- a single source-of-truth value->name table (also used as the ProtoField -- valuestring) and derive the name->value lookup instead of hand-maintaining two. local function invert(t) local r = {} for k, v in pairs(t) do r[v] = k end return r end -- Decode a BCD-encoded byte to a decimal number. Returns nil when either nibble -- is out of range (> 9), which means the byte isn't valid BCD -- e.g. a 0xff -- "not present" sentinel, or a value the device actually encodes in plain -- binary. Callers decide how to present the invalid case. local function bcd2dec(b) local hi = bit.rshift(b, 4) local lo = bit.band(b, 0x0F) if hi > 9 or lo > 9 then return nil end return hi * 10 + lo end -- Format a BCD-encoded mm:ss pair, falling back to raw hex when a byte isn't -- valid BCD (e.g. a 0xff sentinel for "time unknown"). local function bcd_time(min_b, sec_b) local m = bcd2dec(min_b) local s = bcd2dec(sec_b) if m == nil or s == nil then return string.format("%02x:%02x (raw)", min_b, sec_b) end return string.format("%02d:%02d", m, s) end local known_devices = { [0x00] = "LAN", [0x01] = "COMM_CTRL", -- [0x02] = "COM_EXT", -- @GadgetNutt [0x11] = "COMMUNICATION v1", -- @GadgetNutt reads 0x11 as COM_MASTER [0x12] = "COMMUNICATION v2", [0x21] = "SW", -- @GadgetNutt reads 0x21 as SW_AUDIO [0x23] = "SW_NAME", -- @GadgetNutt reads 0x23 as SW_SHIFT [0x24] = "SW_CONVERTING", [0x25] = "CMD_SW", -- @GadgetNutt reads 0x25 as SW [0x31] = "STATUS", -- [0x32] corroborated by @GadgetNutt (INFO_DISPLAY2); sends status report f1 to STATUS (32 31 f1 00 00) [CQ-TS7471LC_bootup] [0x32] = "INFO_DISPLAY2", [0x28] = "BEEP_HU", [0x29] = "BEEP_SPEAKERS", [0x34] = "FRONT_PSNG_MONITOR", -- [0x40] = "TV_TUNER", -- @GadgetNutt [0x43] = "CD_CHANGER2", -- [0x50] = "CD_50", -- @GadgetNutt (CD variants, unconfirmed) -- [0x52] = "CD_52", [0x55] = "BLUETOOTH_TEL", [0x56] = "INFO_DRAWING", [0x58] = "NAV_ECU", -- @GadgetNutt reads 0x58 as NAV_GPS -- [0x5A] = "FM_MULTIPLEX_VICS", -- [0x5B] = "BEACON", -- @GadgetNutt [0x5C] = "CAMERA", [0x5D] = "CLIMATE_DRAWING", [0x5E] = "AUDIO_DRAWING", [0x5F] = "TRIP_INFO_DRAWING", [0x60] = "TUNER", [0x61] = "TAPE_DECK", [0x62] = "CD", [0x63] = "CD_CHANGER", -- [0x64] = "MD", -- @GadgetNutt (MiniDisc) -- [0x65] = "MD_CH", [0x74] = "AUDIO_AMP", [0x80] = "GPS", -- [0x82] = "FM_MULTIPLEX_DATA", -- [0x83] = "OPTICAL_BEACON", -- [0x84] = "RADIO_WAVE_BEACON", -- @GadgetNutt [0x85] = "VOICE_CTRL", -- [0x9A] = "FM_MULTIPLEX_TUNER",-- @GadgetNutt (0xA4 also seen in the A4 01 DB heartbeat) -- 0xc0 corroborated by @GadgetNutt (XM_TUNER, cf. ADDR XM_RADIO_TUNER); exchanges 0xef/0xff with CMD_SW, sends 0xfe to STATUS [douglasheld2-log.pcap] [0xC0] = "XM_TUNER", [0xE0] = "CLIMATE_CTRL_DEV", [0xE5] = "TRIP_INFO", } local known_devices_names = invert(known_devices) local f_from_device = ProtoField.uint8("avclan.from_device", "From device", base.HEX, known_devices) local f_to_device = ProtoField.uint8("avclan.to_device", "To device", base.HEX, known_devices) local f_active_device = ProtoField.uint8("avclan.active_device", "Active device", base.HEX, known_devices) -- Action conventions: -- - REQ/RESP pairs differ by 0x10, where the REQ is the lesser -- - Opposite pairs (e.g. disc up/down, enable/disable, etc.) differ by 0x01, where the "enable" like action is the lesser -- - Separate pairs are often (but not always) separated by 0x01 local known_actions = { -- LAN related [0x01] = "LAN_INIT", [0x58] = "LAN_INIT_COMPLETE", -- Probably not fully correct label pair (based on values), but seem related functionally/sequentially -- [0x5f] = "??", -- COMM_CTRL self-broadcast (01 01 5f 00), frequent in douglasheld2-log.pcap [but abnormal traffic] [0x00] = "LIST_FUNCTIONS_REQ", [0x10] = "LIST_FUNCTIONS_RESP", -- -- [0x02]/[0x12] REQ/RESP pair, COMM_v2 <-> COMM_CTRL. The 0x12 resp carries a -- -- device list, so likely a richer enumeration than 0x00/0x10. (0x12 collides -- -- with the COMMUNICATION v2 device id.) [CQ-TS7471LC_bootup] -- -- @GadgetNutt corroborates the enumeration reading: 0x02=DEVICES_RESPONSE, -- -- 0x12=DEVICES_REQUEST ("devices I want to hear"), 0x13=DEVICES_BROADCAST. -- [0x02] = "??_REQ", -- 12 01 02 [19 00 16 06 19 0d] -- [0x12] = "??_RESP", -- 01 12 12 60 63 43 64 65 40 32 5e ... -- [0x13] = "DEVICES_BROADCAST", -- @GadgetNutt: peripheral broadcasts its logical-device list (b 1FF 01 11 13 ...) [0x08] = "LANCHECK_END_REQ", [0x18] = "LANCHECK_END_RESP", [0x0a] = "LANCHECK_SCAN_REQ", [0x1a] = "LANCHECK_SCAN_RESP", [0x0c] = "LANCHECK_REQ", [0x1c] = "LANCHECK_RESP", -- [0x0d] = "LANCHECK_??_REQ", -- Observed in @marcin's code; no captured examples -- [0x1d] = "LANCHECK_??_RESP", [0x20] = "PING_REQ", -- [0x21] = "??" -- Observed as [00 11 00 21] incorrect 0xf0/INITIAL_REPORT_RESP message (double leading zeros instead of single unicast leading zero) [0x30] = "PING_RESP", [0x42] = "ENABLE_FUNCTION_REQ", [0x52] = "ENABLE_FUNCTION_RESP", [0x43] = "DISABLE_FUNCTION_REQ", [0x53] = "DISABLE_FUNCTION_RESP", [0x45] = "ADVERTISE_FUNCTION", [0x46] = "GENERAL_QUERY", -- Physical actions [0x50] = "INSERTION", [0x51] = "EJECTION", [0x59] = "BACKLIGHT_ADJUST", [0x60] = "BEEP", [0x78] = "SCREEN_PRESS", [0x80] = "EJECT", -- [0x8e] = "??", -- COMM_v2->CD (12 62 8e, no payload) [CQ-TS7471LC_bootup] [0x90] = "DISC_UP", [0x91] = "DISC_DOWN", [0x94] = "TRACK_SEEK_UP", [0x95] = "TRACK_SEEK_DOWN", [0x98] = "TRACK_FAST_FORWARD", [0x99] = "TRACK_REWIND", [0x9c] = "PWRVOL_KNOB_RIGHTHAND_TURN", [0x9d] = "PWRVOL_KNOB_LEFTHAND_TURN", [0x9f] = "TAPE_NOT_READY", -- Uncertain; observed by @marcin [0xa0] = "CD_ENABLE_REPEAT", [0xa1] = "CD_DISABLE_REPEAT", [0xa3] = "CD_ENABLE_DISK_REPEAT", [0xa4] = "CD_DISABLE_DISK_REPEAT", [0xa6] = "CD_ENABLE_SCAN", [0xa7] = "CD_DISABLE_SCAN", [0xa9] = "CD_ENABLE_DISK_SCAN", [0xaa] = "CD_DISABLE_DISK_SCAN", [0xb0] = "CD_ENABLE_RANDOM", [0xb1] = "CD_DISABLE_RANDOM", [0xb3] = "CD_ENABLE_DISK_RANDOM", [0xb4] = "CD_DISABLE_DISK_RANDOM", -- Info-display / trip-computer functions. @GadgetNutt names these; cluster -- around TRIP_INFO/INFO_DISPLAY and the A4 01 DB heartbeat. Unconfirmed here. -- [0xb7] = "STATUS_B7", -- @GadgetNutt -- [0xd9] = "INFO_D9", -- @GadgetNutt (info display, unidentified) -- [0xdb] = "AVG_KMH_INFO", -- @GadgetNutt (average km/h) -- [0xdc] = "INFO_DC", -- @GadgetNutt (unidentified) -- [0xdd] = "FUEL_RANGE_INFO", -- @GadgetNutt -- [0xde] = "TRIP_TIME_INFO", -- @GadgetNutt -- Peripheral state communication request/response [0xe0] = "INITIAL_REPORT_REQ", [0xf0] = "INITIAL_REPORT_RESP", [0xe2] = "PLAYBACK_REQ", [0xf2] = "PLAYBACK_RESP", [0xe4] = "LOADING_REQ", [0xf4] = "LOADING_RESP", [0xed] = "TRACK_NAME_REQ", [0xfd] = "TRACK_NAME_RESP", -- Numerically goes here, but message length (short) tracks more with a LAN related pair -- (Also this was observed early in a capture) -- [0xef] = "??_REQ", -- Observed in broadcast(?) message 190 => 1f1 00 25 c0 ef [douglasheld2-log.pcap] -- [0xff] = "??_RESP", -- Observed in broadcast(?) message 1f1 => 190 00 c0 25 ff 00 [douglasheld2-log.pcap] -- Unprompted peripheral state announcements [0xf1] = "PLAYBACK_STATUS", [0xf3] = "LOADING_STATUS", [0xf9] = "REPORT_TOC", -- [0xfe] = "??", -- dev 0xc0->STATUS (c0 31 fe 00), status-announcement-like [douglasheld2-log.pcap] } local known_actions_names = invert(known_actions) local f_action = ProtoField.uint8("avclan.action", "Action", base.HEX, known_actions) local f_functions = ProtoField.bytes("avclan.functions", "Functions", base.SPACE, "Device functions") local f_ping_count = ProtoField.uint8("avclan.ping.count", "Ping count") local f_backlight = ProtoField.uint8("avclan.backlight.brightness", "Backlight brightness", base.HEX) -- Beep request (AUDIO_DRAWING -> BEEP_SPEAKERS, action 0x60): duration parameter local f_beep_duration = ProtoField.uint8("avclan.beep.duration", "Beep duration", base.DEC) -- Touch-screen press (SW -> SW_CONVERTING, action 0x78): x,y position local f_touch_x = ProtoField.uint8("avclan.touch.x", "Touch X", base.HEX) local f_touch_y = ProtoField.uint8("avclan.touch.y", "Touch Y", base.HEX) local f_radio_active = ProtoField.bool("avclan.radio.active", "Radio", base.NONE, {"ON", "OFF"}) local f_radio_status = ProtoField.uint8("avclan.radio.status", "Radio status", base.HEX, { [0x00] = "OFF", [0x01] = "READY", [0x06] = "SCAN UP", [0x07] = "SCAN DOWN", [0x0A] = "AST SEARCH", [0x27] = "MANUAL" } ) local f_radio_flags = ProtoField.uint8("avclan.radio.flags", "Radio flags") local f_radio_flags2 = ProtoField.uint8("avclan.radio.flags2", "Radio flags (byte 2)") -- Preset/channel number (0 when not on a stored preset). local f_radio_channel = ProtoField.uint8("avclan.radio.channel", "Preset channel", base.DEC) -- NOTE: bit 0x04 is read here as Stereo. @enkiusz (TunerFlags) reads the same -- bit as TP (Traffic Programme). One of these is wrong; unresolved. local f_radioflag_st = ProtoField.bool("avclan.radio.flags.st", "Stereo", 8, {"Set", "Not set"}, 0x04) local f_radioflag_ta = ProtoField.bool("avclan.radio.flags.ta", "TA", 8, {"Set", "Not set"}, 0x08) local f_radioflag_reg = ProtoField.bool("avclan.radio.flags.reg", "REG", 8, {"Set", "Not set"}, 0x10) local f_radioflag_af = ProtoField.bool("avclan.radio.flags.af", "AF", 8, {"Set", "Not set"}, 0x40) local f_radio_band = ProtoField.uint8("avclan.radio.band", "Radio band", base.HEX, {[0x8] = "FM", [0xC] = "AM (Long-wave)", [0x0] = "AM (Medium-wave)"}, 0xF0) local f_radio_bandnumber = ProtoField.int8("avclan.radio.bandnumber", "Radio band number", base.DEC, nil, 0x0F) local f_radio_freq = ProtoField.uint16("avclan.radio.freq", "Radio frequency") -- Volume is BCD encoded here. NOTE: @enkiusz treats the volume byte as plain -- binary (no BCD conversion); the two disagree for values with a nibble > 9. local f_amp_volume = ProtoField.uint8("avclan.amp.volume", "Volume", base.DEC) -- Amp bass, mid, treble, fade, and balance are offset-binary (offset-16) encoded local f_amp_bass = ProtoField.uint8("avclan.amp.bass", "Bass", base.HEX, { [0x0B] = "-5", [0x0C] = "-4", [0x0D] = "-3", [0x0E] = "-2", [0x0F] = "-1", [0x10] = "0", [0x11] = "+1", [0x12] = "+2", [0x13] = "+3", [0x14] = "+4", [0x15] = "+5" }) local f_amp_mid = ProtoField.uint8("avclan.amp.mid", "Mid", base.HEX, { [0x0B] = "-5", [0x0C] = "-4", [0x0D] = "-3", [0x0E] = "-2", [0x0F] = "-1", [0x10] = "0", [0x11] = "+1", [0x12] = "+2", [0x13] = "+3", [0x14] = "+4", [0x15] = "+5" }) local f_amp_treble = ProtoField.uint8("avclan.amp.treble", "Treble", base.HEX, { [0x0B] = "-5", [0x0C] = "-4", [0x0D] = "-3", [0x0E] = "-2", [0x0F] = "-1", [0x10] = "0", [0x11] = "+1", [0x12] = "+2", [0x13] = "+3", [0x14] = "+4", [0x15] = "+5" }) local f_amp_fade = ProtoField.uint8("avclan.amp.fade", "Fade (forward/rear)", base.HEX, { [0x09] = "-7", [0x0A] = "-6", [0x0B] = "-5", [0x0C] = "-4", [0x0D] = "-3", [0x0E] = "-2", [0x0F] = "-1", [0x10] = "0", [0x11] = "+1", [0x12] = "+2", [0x13] = "+3", [0x14] = "+4", [0x15] = "+5", [0x16] = "+6", [0x17] = "+7" }) local f_amp_balance = ProtoField.uint8("avclan.amp.balance", "Balance (right/left)", base.HEX, { [0x09] = "-7", [0x0A] = "-6", [0x0B] = "-5", [0x0C] = "-4", [0x0D] = "-3", [0x0E] = "-2", [0x0F] = "-1", [0x10] = "0", [0x11] = "+1", [0x12] = "+2", [0x13] = "+3", [0x14] = "+4", [0x15] = "+5", [0x16] = "+6", [0x17] = "+7" }) -- Amp status flags (from @enkiusz's AudioAmpFlags). Only MUTE (0x04) is -- identified; the rest are unknown. Note this byte (data_bytes[12]) sits past -- the end of the 14-byte amp reports in our captures, so it only decodes on -- longer report variants. local f_amp_flags = ProtoField.uint8("avclan.amp.flags", "Amplifier flags", base.HEX) local f_amp_mute = ProtoField.bool("avclan.amp.flags.mute", "MUTE", 8, nil, 0x04) local f_cd_slots = ProtoField.uint8("avclan.cd.slots", "CD player disc slots") local f_cd_slot1 = ProtoField.bool("avclan.cd.slot1", "Slot 1", 6, {"Filled", "Empty"}, 0x01) local f_cd_slot2 = ProtoField.bool("avclan.cd.slot1", "Slot 2", 6, {"Filled", "Empty"}, 0x02) local f_cd_slot3 = ProtoField.bool("avclan.cd.slot1", "Slot 3", 6, {"Filled", "Empty"}, 0x04) local f_cd_slot4 = ProtoField.bool("avclan.cd.slot1", "Slot 4", 6, {"Filled", "Empty"}, 0x08) local f_cd_slot5 = ProtoField.bool("avclan.cd.slot1", "Slot 5", 6, {"Filled", "Empty"}, 0x10) local f_cd_slot6 = ProtoField.bool("avclan.cd.slot1", "Slot 6", 6, {"Filled", "Empty"}, 0x20) local f_cd_state = ProtoField.uint8("avclan.cd.state", "CD player state") local f_cd_open = ProtoField.bool("avclan.cd.state.open", "OPEN", 8, nil, 0x01) local f_cd_err1 = ProtoField.bool("avclan.cd.state.err1", "ERR1", 8, nil, 0x02) local f_cd_seeking = ProtoField.bool("avclan.cd.state.seeking", "SEEKING", 8, nil, 0x08) local f_cd_playback = ProtoField.bool("avclan.cd.state.playback", "PLAYBACK", 8, nil, 0x10) local f_cd_seeking_track = ProtoField.bool("avclan.cd.state.seeking_track", "SEEKING_TRACK", 8, nil, 0x20) local f_cd_loading = ProtoField.bool("avclan.cd.state.loading", "LOADING", 8, nil, 0x80) local f_cd_disc = ProtoField.uint8("avclan.cd.disc", "Current disc", base.DEC) local f_cd_track = ProtoField.uint8("avclan.cd.track", "Track number", base.HEX) local f_cd_track_count = ProtoField.uint8("avclan.cd.track_count", "Track count", base.DEC) local f_cd_title = ProtoField.string("avclan.cd.title", "Track/disc title") local f_cd_min = ProtoField.uint8("avclan.cd.mins", "CD track play time, minutes", base.HEX) local f_cd_sec = ProtoField.uint8("avclan.cd.secs", "CD track play time, seconds", base.HEX) local f_cd_flags = ProtoField.uint8("avclan.cd.flags", "CD player flags") local f_cd_flag_disk_random = ProtoField.bool("avclan.cd.flags.disk_random", "DISK_RANDOM", 8, nil, 0x02) local f_cd_flag_random = ProtoField.bool("avclan.cd.flags.random", "RANDOM", 8, nil, 0x04) local f_cd_flag_disk_repeat = ProtoField.bool("avclan.cd.flags.disk_repeat", "DISK_REPEAT", 8, nil, 0x08) local f_cd_flag_repeat = ProtoField.bool("avclan.cd.flags.repeat", "REPEAT", 8, nil, 0x10) local f_cd_flag_disk_scan = ProtoField.bool("avclan.cd.flags.disk_scan", "DISK_SCAN", 8, nil, 0x20) local f_cd_flag_scan = ProtoField.bool("avclan.cd.flags.scan", "SCAN", 8, nil, 0x40) local f_tape_present = ProtoField.uint8("avclan.tape.present", "Tape deck slot", base.HEX, {[0x01] = "FILLED", [0x00] = "EMPTY"}) local f_tape_state = ProtoField.uint8("avclan.tape.state", "Tape deck state") local f_tape_seeking_rev = ProtoField.bool("avclan.tape.state.seeking_rev", "SEEKING_REVERSE", 8, nil, 0x01) local f_tape_err1 = ProtoField.bool("avclan.tape.state.err1", "ERR1", 8, nil, 0x02) local f_tape_playback = ProtoField.bool("avclan.tape.state.playback", "PLAYBACK", 8, nil, 0x04) local f_tape_seeking = ProtoField.bool("avclan.tape.state.seeking", "SEEKING", 8, nil, 0x08) local f_tape_state1 = ProtoField.bool("avclan.tape.state.unknown1", "UNKOWN1", 8, nil, 0x10) local f_tape_random = ProtoField.bool("avclan.tape.state.random", "RANDOM", 8, nil, 0x80) local f_tape_flags = ProtoField.uint16("avclan.tape.flags", "Tape deck flags") local f_tape_stereo = ProtoField.bool("avclan.tape.flags.stereo", "STEREO", 16, nil, 0x0004) local f_tape_dolby = ProtoField.bool("avclan.tape.flags.dolby", "DOLBY", 16, nil, 0x0002) local f_tape_flag1 = ProtoField.bool("avclan.tape.flags.flag1", "UNKNOWN1", 16, nil, 0x0100) local f_tape_flag2 = ProtoField.bool("avclan.tape.flags.flag2", "UNKNOWN2", 16, nil, 0x1000) local f_tape_flag3 = ProtoField.bool("avclan.tape.flags.flag3", "UNKNOWN3", 16, nil, 0x2000) local f_tape_flag4 = ProtoField.bool("avclan.tape.flags.flag4", "UNKNOWN4", 16, nil, 0x8000) avclanproto.fields = { f_from_device, f_to_device, f_active_device, f_action, f_functions, f_ping_count, f_backlight, f_beep_duration, f_touch_x, f_touch_y, f_radio_active, f_radio_status, f_radio_flags, f_radio_flags2, f_radio_band, f_radio_bandnumber, f_radio_freq, f_radio_channel, f_radioflag_af, f_radioflag_reg, f_radioflag_st, f_radioflag_ta, f_amp_volume, f_amp_bass, f_amp_mid, f_amp_treble, f_amp_fade, f_amp_balance, f_amp_flags, f_amp_mute, f_cd_slots, f_cd_slot1, f_cd_slot2, f_cd_slot3, f_cd_slot4, f_cd_slot5, f_cd_slot6, f_cd_state, f_cd_open, f_cd_err1, f_cd_seeking, f_cd_playback, f_cd_seeking_track, f_cd_loading, f_cd_disc, f_cd_track, f_cd_track_count, f_cd_title, f_cd_min, f_cd_sec, f_cd_flags, f_cd_flag_disk_random, f_cd_flag_random, f_cd_flag_disk_repeat, f_cd_flag_repeat, f_cd_flag_disk_scan, f_cd_flag_scan, f_tape_present, f_tape_state, f_tape_seeking_rev, f_tape_err1, f_tape_playback, f_tape_seeking, f_tape_state1, f_tape_random, f_tape_flags, f_tape_stereo, f_tape_dolby, f_tape_flag1, f_tape_flag2, f_tape_flag3, f_tape_flag4, } local pe_unhandled_msg = ProtoExpert.new("avclan.expert", "Message not decoded", expert.group.UNDECODED, expert.severity.WARN) -- Parsed-but-unrecognized header values: the frame structure is understood, only -- the device/action byte is absent from our lookup tables. NOTE severity (vs the -- WARN above) keeps these distinct from genuinely undecodable payloads, and the -- dedicated abbreviations make each independently filterable in Wireshark. local pe_unknown_device = ProtoExpert.new("avclan.unknown_device.expert", "Unknown device address", expert.group.UNDECODED, expert.severity.NOTE) local pe_unknown_action = ProtoExpert.new("avclan.unknown_action.expert", "Unknown action", expert.group.UNDECODED, expert.severity.NOTE) -- local pe_lan_check = ProtoExpert.new("avclan.lan.expert", "") local pe_ping_req = ProtoExpert.new("avclan.ping_req.expert", "Ping request", expert.group.SEQUENCE, expert.severity.CHAT) local pe_ping_resp = ProtoExpert.new("avclan.ping_resp.expert", "Ping response", expert.group.SEQUENCE, expert.severity.CHAT) avclanproto.experts = { pe_unhandled_msg, pe_unknown_device, pe_unknown_action, pe_ping_req, pe_ping_resp, } local field_from_device = Field.new("avclan.from_device") local field_to_device = Field.new("avclan.to_device") local field_action = Field.new("avclan.action") local field_radio_freq = Field.new("avclan.radio.freq") local field_radio_band = Field.new("avclan.radio.band") local field_cd_disc = Field.new("avclan.cd.disc") local field_cd_track = Field.new("avclan.cd.track") local field_cd_min = Field.new("avclan.cd.mins") local field_cd_sec = Field.new("avclan.cd.secs") -- Attach the "not decoded" expert warning to a specific byte range rather than -- the whole message, so Wireshark highlights exactly the bytes we don't yet -- understand. local function mark_undecoded(tree, range) tree:add(range, "Undecoded bytes"):add_proto_expert_info(pe_unhandled_msg) end -- Add a device-address field (from/to/active), attaching an expert note when the -- byte isn't a known device so the frame is filterable via -- `avclan.unknown_device.expert`. Returns the item so callers can chain off it. local function add_device(tree, field, range) local item = tree:add(field, range) if known_devices[range:uint()] == nil then item:add_proto_expert_info(pe_unknown_device) end return item end -- Add the action field, attaching an expert note when the byte isn't a known -- action (filterable via `avclan.unknown_action.expert`). Returns the item. local function add_action(tree, range) local item = tree:add(f_action, range) if known_actions[range:uint()] == nil then item:add_proto_expert_info(pe_unknown_action) end return item end -- --------------------------------------------------------------------------- -- Per-message decoders. -- -- Each decoder receives the message `subtree`, the `buffer`, and `offset` (the -- index of the `from` byte, accounting for the leading 0x00 on unicast frames). -- Device-state decoders also receive the resolved `action`. The dissector body -- below is just a router that selects one of these based on from/to/action, -- preserving the historical precedence order. -- --------------------------------------------------------------------------- -- CMD_SW source. Sub-commands to the amplifier (actions 0x90-0x95) set a -- tone/level control; these codes collide with physical-interface actions, so -- the CMD_SW -> AUDIO_AMP device pair disambiguates them. local function decode_cmd_sw(subtree, buffer, offset, to_device) add_action(subtree, buffer(offset+2,1)) local action = field_action().value if to_device == known_devices_names["AUDIO_AMP"] then local amptree = subtree:add(avclanproto, buffer(offset+2,-1), "Device: Audio amplifier control") local param = buffer(offset+3,1) if action == 0x90 then -- VOLUME (BCD) local vol_raw = param:uint() amptree:add(f_amp_volume, param, bcd2dec(vol_raw) or vol_raw):append_text(" (VOLUME)") elseif action == 0x91 then amptree:add(f_amp_balance, param) elseif action == 0x92 then amptree:add(f_amp_fade, param) elseif action == 0x93 then amptree:add(f_amp_bass, param) elseif action == 0x94 then amptree:add(f_amp_mid, param) elseif action == 0x95 then amptree:add(f_amp_treble, param) end end end -- COMMUNICATION v1/v2 source. local function decode_from_comm(subtree, buffer, offset, to_device) if to_device == known_devices_names["COMM_CTRL"] then add_action(subtree, buffer(offset+2,1)) local action = field_action().value if action == known_actions_names["ADVERTISE_FUNCTION"] then add_device(subtree, f_active_device, buffer(offset+3,1)) elseif action == known_actions_names["PING_REQ"] then subtree:add(f_ping_count, buffer(offset+3,1)) subtree:add_proto_expert_info(pe_ping_req, "Ping request " .. buffer(offset+3,1):uint()) elseif known_actions[action] then else subtree:add_proto_expert_info(pe_unhandled_msg) end else -- Control actions addressed to a peripheral rather than COMM_CTRL, e.g. -- function enable/disable (COMM_v1/v2 -> CD_CHANGER, 0x42/0x43). These -- are understood apart from a trailing 0x01 of unknown meaning. add_action(subtree, buffer(offset+2,1)) end end -- COMM_CTRL source. local function decode_from_commctrl(subtree, buffer, offset, to_device) if to_device == known_devices_names["COMMUNICATION v1"] or to_device == known_devices_names["COMMUNICATION v2"] then local action_tree = add_action(subtree, buffer(offset+2,1)) local action = field_action().value if action == known_actions_names["PING_RESP"] then subtree:add(f_ping_count, buffer(offset+3,1)) subtree:add_proto_expert_info(pe_ping_resp, "Ping response " .. buffer(offset+3,1):uint()) elseif action == known_actions_names["LIST_FUNCTIONS_RESP"] then local functions = action_tree:add(f_functions, buffer(offset+3)) functions:append_text(" (") for v = 0,(buffer:bytes(offset+3)):len()-1 do if known_devices[buffer(offset+3+v,1):uint()] then functions:append_text(" " .. known_devices[buffer(offset+3+v,1):uint()]) else functions:append_text(" UNKNOWN_DEVICE") end end functions:append_text(" ) ") elseif known_actions[action] then else subtree:add_proto_expert_info(pe_unhandled_msg) end elseif to_device == known_devices_names["COMM_CTRL"] then local action_tree = add_action(subtree, buffer(offset+2,1)) local action = field_action().value if action == known_actions_names["BACKLIGHT_ADJUST"] then local backlight = subtree:add(f_backlight, buffer(offset+3,1)) backlight:append_text(" (" .. math.floor(100*(63 - buffer(offset+3,1):uint())/63) .. ")") end elseif to_device == known_actions_names["LANCHECK_SCAN_REQ"] or to_device == known_actions_names["LANCHECK_REQ"] or to_device == known_actions_names["LANCHECK_END_REQ"] then add_action(subtree, buffer(offset+1,1)) elseif to_device == 0x00 then add_action(subtree, buffer(offset+2,1)) else subtree:add_proto_expert_info(pe_unhandled_msg) end end -- Beep request (any source -> BEEP_SPEAKERS), action 0x60 with a duration byte. local function decode_beep(subtree, buffer, offset) add_action(subtree, buffer(offset+2,1)) local action = field_action().value if action == known_actions_names["BEEP"] then subtree:add(f_beep_duration, buffer(offset+3,1)) else subtree:add_proto_expert_info(pe_unhandled_msg) end end -- TUNER source: radio state dump (regardless of action). local function decode_radio(subtree, buffer, offset, action) local radiotree = subtree:add(avclanproto, buffer(offset), "Device: Radio") radiotree:add_le(f_radio_active, buffer(offset+3,1)) radiotree:add_le(f_radio_status, buffer(offset+4,1)) radiotree:add_le(f_radio_band, buffer(offset+5,1)) radiotree:add(f_radio_bandnumber, buffer(offset+5,1)) local freqtree = radiotree:add(f_radio_freq, buffer(offset+6,2)) local radio_band = buffer(offset+5,1):uint() local freq = field_radio_freq().value if bit.band(radio_band, 0xF0) == 0x80 then freqtree:append_text(" (" .. 87.5+(freq-1)*.05 .. " MHz)") elseif bit.band(radio_band, 0xF0) == 0xC0 then freqtree:append_text(" (" .. 153+(freq-1)*1 .. " kHz)") elseif bit.band(radio_band, 0xF0) == 0x00 then freqtree:append_text(" (" .. 522+(freq-1)*9 .. " kHz)") end -- Preset channel number (@enkiusz's pd.py byte 6); 0 means "not on a preset". if buffer:len() > offset+8 then local channel = buffer(offset+8,1) radiotree:add(f_radio_channel, channel) if channel:uint() > 0 then radiotree:append_text(", preset #" .. channel:uint()) end end -- Flags are offset-relative (@enkiusz's pd.py bytes 7 and 8); earlier -- versions of this dissector read them at the fixed absolute offsets 15/16. if buffer:len() > offset+9 then local flags = radiotree:add(f_radio_flags, buffer(offset+9,1)) flags:add(f_radioflag_st, buffer(offset+9,1)) flags:add(f_radioflag_ta, buffer(offset+9,1)) flags:add(f_radioflag_reg, buffer(offset+9,1)) flags:add(f_radioflag_af, buffer(offset+9,1)) end if buffer:len() > offset+10 then radiotree:add(f_radio_flags2, buffer(offset+10,1)) end end -- AUDIO_AMP source: amplifier state dump (regardless of action). local function decode_amp(subtree, buffer, offset, action) -- Span to end of buffer rather than a fixed length: the flags byte (offset+14) -- isn't present in every amp frame, and a fixed range would run out of bounds. local amptree = subtree:add(avclanproto, buffer(offset), "Device: Audio amplifier") local vol_raw = buffer(offset+4,1):uint() amptree:add(f_amp_volume, buffer(offset+4,1), bcd2dec(vol_raw) or vol_raw) amptree:add(f_amp_balance, buffer(offset+5,1)) amptree:add(f_amp_fade, buffer(offset+6,1)) amptree:add(f_amp_bass, buffer(offset+7,1)) amptree:add(f_amp_mid, buffer(offset+8,1)) amptree:add(f_amp_treble, buffer(offset+9,1)) -- Status flags (@enkiusz's pd.py byte 11); only MUTE (0x04) is identified. if buffer:len() > offset+14 then local amp_flags = amptree:add(f_amp_flags, buffer(offset+14,1)) amp_flags:add(f_amp_mute, buffer(offset+14,1)) end end -- CD / CD_CHANGER source: payload depends on the report action. local function decode_cd(subtree, buffer, offset, action) if action == known_actions_names["PLAYBACK_STATUS"] or action == known_actions_names["PLAYBACK_RESP"] then local cdtree = subtree:add(avclanproto, buffer(offset,9), "Device: CD player") local cd_slots = cdtree:add(f_cd_slots, buffer(offset+3,1)) cd_slots:add(f_cd_slot1, buffer(offset+3,1)) cd_slots:add(f_cd_slot2, buffer(offset+3,1)) cd_slots:add(f_cd_slot3, buffer(offset+3,1)) cd_slots:add(f_cd_slot4, buffer(offset+3,1)) cd_slots:add(f_cd_slot5, buffer(offset+3,1)) cd_slots:add(f_cd_slot6, buffer(offset+3,1)) local cd_state = cdtree:add(f_cd_state, buffer(offset+4,1)) cd_state:add(f_cd_open, buffer(offset+4,1)) cd_state:add(f_cd_err1, buffer(offset+4,1)) cd_state:add(f_cd_seeking, buffer(offset+4,1)) cd_state:add(f_cd_playback, buffer(offset+4,1)) cd_state:add(f_cd_seeking_track, buffer(offset+4,1)) cd_state:add(f_cd_loading, buffer(offset+4,1)) local cd_status = cdtree:add(avclanproto, buffer(offset+5,-1), "") cd_status:add(f_cd_disc, buffer(offset+5,1)) cd_status:add(f_cd_track, buffer(offset+6,1)) cd_status:add(f_cd_min, buffer(offset+7,1)) cd_status:add(f_cd_sec, buffer(offset+8,1)) cd_status:append_text("Disc " .. field_cd_disc().value .. ", ") cd_status:append_text("track " .. tostring(buffer(offset+6,1)):gsub("(.)(.)", "%1%2") .. ", ") cd_status:append_text("time " .. bcd_time(buffer(offset+7,1):uint(), buffer(offset+8,1):uint())) local cd_flags = cdtree:add(f_cd_flags, buffer(offset+9,1)) cd_flags:add(f_cd_flag_disk_random, buffer(offset+9,1)) cd_flags:add(f_cd_flag_random, buffer(offset+9,1)) cd_flags:add(f_cd_flag_disk_repeat, buffer(offset+9,1)) cd_flags:add(f_cd_flag_repeat, buffer(offset+9,1)) cd_flags:add(f_cd_flag_disk_scan, buffer(offset+9,1)) cd_flags:add(f_cd_flag_scan, buffer(offset+9,1)) elseif action == known_actions_names["LOADING_STATUS"] or action == known_actions_names["LOADING_RESP"] then local cdtree = subtree:add(avclanproto, buffer(offset,9), "Device: CD player") local available_slots = cdtree:add(f_cd_slots, buffer(offset+4,1)) available_slots:add(f_cd_slot1, buffer(offset+4,1)) available_slots:add(f_cd_slot2, buffer(offset+4,1)) available_slots:add(f_cd_slot3, buffer(offset+4,1)) available_slots:add(f_cd_slot4, buffer(offset+4,1)) available_slots:add(f_cd_slot5, buffer(offset+4,1)) available_slots:add(f_cd_slot6, buffer(offset+4,1)) local occupied_slots = cdtree:add(f_cd_slots, buffer(offset+6,1)) occupied_slots:add(f_cd_slot1, buffer(offset+6,1)) occupied_slots:add(f_cd_slot2, buffer(offset+6,1)) occupied_slots:add(f_cd_slot3, buffer(offset+6,1)) occupied_slots:add(f_cd_slot4, buffer(offset+6,1)) occupied_slots:add(f_cd_slot5, buffer(offset+6,1)) occupied_slots:add(f_cd_slot6, buffer(offset+6,1)) local redundant_slots = cdtree:add(f_cd_slots, buffer(offset+8,1)) redundant_slots:add(f_cd_slot1, buffer(offset+8,1)) redundant_slots:add(f_cd_slot2, buffer(offset+8,1)) redundant_slots:add(f_cd_slot3, buffer(offset+8,1)) redundant_slots:add(f_cd_slot4, buffer(offset+8,1)) redundant_slots:add(f_cd_slot5, buffer(offset+8,1)) redundant_slots:add(f_cd_slot6, buffer(offset+8,1)) local cd_state = cdtree:add(f_cd_state, buffer(offset+9,1)) cd_state:add(f_cd_open, buffer(offset+9,1)) cd_state:add(f_cd_err1, buffer(offset+9,1)) cd_state:add(f_cd_seeking, buffer(offset+9,1)) cd_state:add(f_cd_playback, buffer(offset+9,1)) cd_state:add(f_cd_seeking_track, buffer(offset+9,1)) cd_state:add(f_cd_loading, buffer(offset+9,1)) elseif action == known_actions_names["REPORT_TOC"] then -- Disc table-of-contents (@enkiusz's REPORT_TOC layout). local toctree = subtree:add(avclanproto, buffer(offset), "Device: CD player (TOC)") toctree:add(f_cd_disc, buffer(offset+3,1)) toctree:add(f_cd_track, buffer(offset+4,1)):append_text(" (first track)") toctree:add(f_cd_track_count, buffer(offset+5,1)) local total = bcd_time(buffer(offset+6,1):uint(), buffer(offset+7,1):uint()) toctree:append_text(", total time " .. total) elseif action == known_actions_names["TRACK_NAME_RESP"] then -- Track-name report: disc/track then an ASCII title (@enkiusz's pd.py: -- title starts at data byte 5). local nametree = subtree:add(avclanproto, buffer(offset,-1), "Device: CD player (track name)") nametree:add(f_cd_disc, buffer(offset+3,1)) nametree:add(f_cd_track, buffer(offset+4,1)) if buffer:len() > offset+7 then local title = nametree:add(f_cd_title, buffer(offset+7)) title:append_text(" (\"" .. buffer(offset+7):string() .. "\")") end elseif action == known_actions_names["ENABLE_FUNCTION_RESP"] or action == known_actions_names["DISABLE_FUNCTION_RESP"] then -- Understood apart from a trailing 0x01 of unknown meaning; not flagged. elseif buffer:len() > offset+3 then -- Recognized CD action (initial report 0xf0, TOC 0xf9, track name -- 0xfd, ...) whose payload layout isn't understood yet. Flag just the -- undecoded bytes, not the whole (correctly-named) message. mark_undecoded(subtree, buffer(offset+3)) end end -- CD / CD_CHANGER destination: requests addressed to a CD player. Only the -- track-name request carries a decodable payload (@enkiusz's pkt_to_cd_player); -- other request actions are identified by their action byte alone. local function decode_to_cd(subtree, buffer, offset, action) if action == known_actions_names["TRACK_NAME_REQ"] then subtree:add(f_cd_disc, buffer(offset+3,1)) subtree:add(f_cd_track, buffer(offset+4,1)) end end -- TAPE_DECK source: tape state dump on PLAYBACK_STATUS local function decode_tape(subtree, buffer, offset, action) if action == known_actions_names["PLAYBACK_STATUS"] then local tapetree = subtree:add(avclanproto, buffer(offset,4), "Device: Tape deck") tapetree:add(f_tape_present, buffer(offset+3,1)) local tape_state = tapetree:add(f_tape_state, buffer(offset+4,1)) tape_state:add(f_tape_seeking_rev, buffer(offset+4,1)) tape_state:add(f_tape_err1, buffer(offset+4,1)) tape_state:add(f_tape_playback, buffer(offset+4,1)) tape_state:add(f_tape_seeking, buffer(offset+4,1)) tape_state:add(f_tape_state1, buffer(offset+4,1)) tape_state:add(f_tape_random, buffer(offset+4,1)) local tape_flags = tapetree:add(f_tape_flags, buffer(offset+5,2)) tape_flags:add(f_tape_stereo, buffer(offset+5,2)) tape_flags:add(f_tape_dolby, buffer(offset+5,2)) tape_flags:add(f_tape_flag1, buffer(offset+5,2)) tape_flags:add(f_tape_flag2, buffer(offset+5,2)) tape_flags:add(f_tape_flag3, buffer(offset+5,2)) tape_flags:add(f_tape_flag4, buffer(offset+5,2)) end end -- SW source: touch-screen press (action 0x78) with x,y position pairs. local function decode_touch(subtree, buffer, offset, action) if action == known_actions_names["SCREEN_PRESS"] then subtree:add(f_touch_x, buffer(offset+3,1)) subtree:add(f_touch_y, buffer(offset+4,1)) if buffer:len() > offset+6 then subtree:add(f_touch_x, buffer(offset+5,1)):append_text(" (2)") subtree:add(f_touch_y, buffer(offset+6,1)):append_text(" (2)") end else subtree:add_proto_expert_info(pe_unhandled_msg) end end -- Device-state report decoders, keyed by the originating device. For these, -- the from_device determines the payload format; the action (passed through) -- only matters within CD/tape/touch. local device_decoders = { [known_devices_names["TUNER"]] = decode_radio, [known_devices_names["AUDIO_AMP"]] = decode_amp, [known_devices_names["CD"]] = decode_cd, [known_devices_names["CD_CHANGER"]] = decode_cd, [known_devices_names["TAPE_DECK"]] = decode_tape, [known_devices_names["SW"]] = decode_touch, } function avclanproto.dissector(buffer, pinfo, tree) local length = buffer:len() if length == 0 then return end iebusproto.dissector(buffer, pinfo, tree) local subtree = tree:add(avclanproto, buffer(7,-1), "AVCLAN message") -- Unicast device-to-device frames carry a leading 0x00 before the from/to -- bytes; skip it so `offset` always points at the `from` byte. local offset = 7 if buffer(7,1):uint() == 0 then offset = 8 elseif buffer(0,1):uint() ~= 0 then -- Unicast frame whose leading byte isn't the expected 0x00 pad (e.g. -- 0xff). @enkiusz notes both 0x00 and 0xff occur here, but under the -- current protocol understanding a non-0x00 prefix is unusual; rather -- than risk misaligning every downstream field, treat it conservatively -- as undecoded. subtree:add_proto_expert_info(pe_unhandled_msg) return end add_device(subtree, f_from_device, buffer(offset+0,1)) add_device(subtree, f_to_device, buffer(offset+1,1)) local from_device = field_from_device().value local to_device = field_to_device().value if from_device == known_devices_names["CMD_SW"] then decode_cmd_sw(subtree, buffer, offset, to_device) elseif from_device == known_devices_names["COMMUNICATION v1"] or from_device == known_devices_names["COMMUNICATION v2"] then decode_from_comm(subtree, buffer, offset, to_device) elseif from_device == known_devices_names["COMM_CTRL"] then decode_from_commctrl(subtree, buffer, offset, to_device) elseif to_device == known_devices_names["BEEP_SPEAKERS"] then decode_beep(subtree, buffer, offset) elseif from_device == known_devices_names["STATUS"] and known_devices[to_device] ~= nil then add_action(subtree, buffer(offset+2,1)) elseif device_decoders[from_device] then add_action(subtree, buffer(offset+2,1)) device_decoders[from_device](subtree, buffer, offset, field_action().value) elseif to_device == known_devices_names["CD"] or to_device == known_devices_names["CD_CHANGER"] then add_action(subtree, buffer(offset+2,1)) decode_to_cd(subtree, buffer, offset, field_action().value) else -- Unknown source/dest: the [from, to, action] header layout still holds -- even when we can't decode the body, so surface the action. if buffer:len() > offset+2 then add_action(subtree, buffer(offset+2,1)) end subtree:add_proto_expert_info(pe_unhandled_msg) end end -- for i,v in ipairs(DissectorTable.list()) do print(v) end udlt:add(wtap.USER15, avclanproto)