Livox LiDAR Protocol Wireshark plugin

livox.lua

-- Livox Mid-40 Protocol Dissector
-- Based on Livox SDK Communication Protocol v1.3.0
-- Compatible with older Wireshark versions

local livox_proto = Proto("livox", "Livox Mid-40 Protocol")

-- Protocol fields
local fields = livox_proto.fields
fields.sof = ProtoField.uint8("livox.sof", "Start of Frame", base.HEX)
fields.version = ProtoField.uint8("livox.version", "Protocol Version", base.DEC)
fields.length = ProtoField.uint16("livox.length", "Frame Length", base.DEC)
fields.cmd_type = ProtoField.uint8("livox.cmd_type", "Command Type", base.HEX, {
    [0x00] = "CMD (Request)",
    [0x01] = "ACK (Response)", 
    [0x02] = "MSG (Message)"
})
fields.seq_num = ProtoField.uint16("livox.seq_num", "Sequence Number", base.DEC)
fields.crc16 = ProtoField.uint16("livox.crc16", "Header CRC16", base.HEX)
fields.data = ProtoField.bytes("livox.data", "Data")
fields.crc32 = ProtoField.uint32("livox.crc32", "Frame CRC32", base.HEX)

-- Command data fields
fields.cmd_set = ProtoField.uint8("livox.cmd_set", "Command Set", base.HEX, {
    [0x00] = "General Command Set",
    [0x01] = "LiDAR Command Set",
    [0x02] = "Hub Command Set"
})
fields.cmd_id = ProtoField.uint8("livox.cmd_id", "Command ID", base.HEX)
fields.cmd_data = ProtoField.bytes("livox.cmd_data", "Command Data")

-- Point cloud data fields
fields.pc_version = ProtoField.uint8("livox.pc.version", "Packet Version", base.DEC)
fields.slot_id = ProtoField.uint8("livox.pc.slot_id", "Slot ID", base.DEC)
fields.lidar_id = ProtoField.uint8("livox.pc.lidar_id", "LiDAR ID", base.DEC, {
    [1] = "Mid-100 Left / Mid-40 / Tele-15 / Horizon",
    [2] = "Mid-100 Middle",
    [3] = "Mid-100 Right"
})
fields.reserved = ProtoField.uint8("livox.pc.reserved", "Reserved", base.HEX)
fields.status_code = ProtoField.uint32("livox.pc.status_code", "Status Code", base.HEX)
fields.timestamp_type = ProtoField.uint8("livox.pc.timestamp_type", "Timestamp Type", base.DEC, {
    [0] = "No sync source",
    [1] = "PTP",
    [3] = "GPS",
    [4] = "PPS"
})
fields.data_type = ProtoField.uint8("livox.pc.data_type", "Data Type", base.DEC, {
    [0] = "Cartesian Coordinate",
    [1] = "Spherical Coordinate",
    [6] = "IMU Data"
})
fields.timestamp = ProtoField.uint64("livox.pc.timestamp", "Timestamp", base.DEC)
fields.point_data = ProtoField.bytes("livox.pc.point_data", "Point Cloud Data")

-- Broadcast message fields
fields.broadcast_code = ProtoField.string("livox.broadcast_code", "Broadcast Code")
fields.dev_type = ProtoField.uint8("livox.dev_type", "Device Type", base.DEC, {
    [0] = "Livox Hub",
    [1] = "Mid-40",
    [2] = "Tele-15", 
    [3] = "Horizon",
    [6] = "Mid-70",
    [7] = "Avia"
})

-- Status code breakdown
fields.temp_status = ProtoField.uint8("livox.status.temp", "Temperature Status", base.DEC, {
    [0] = "Normal",
    [1] = "High or Low",
    [2] = "Extremely High or Low"
})
fields.volt_status = ProtoField.uint8("livox.status.volt", "Voltage Status", base.DEC, {
    [0] = "Normal",
    [1] = "High",
    [2] = "Extremely High"
})
fields.motor_status = ProtoField.uint8("livox.status.motor", "Motor Status", base.DEC, {
    [0] = "Normal",
    [1] = "Warning",
    [2] = "Error"
})

function livox_proto.dissector(buffer, pinfo, tree)
    local length = buffer:len()
    if length == 0 then return end

    pinfo.cols.protocol = livox_proto.name

    local subtree = tree:add(livox_proto, buffer(), "Livox Protocol Data")

    -- Check if this is a control command frame (starts with 0xAA)
    if length >= 11 and buffer(0,1):uint() == 0xAA then
        dissect_control_frame(buffer, pinfo, subtree)
    -- Check if this is point cloud data (starts with version 5)
    elseif length >= 18 and buffer(0,1):uint() == 0x05 then
        dissect_point_cloud(buffer, pinfo, subtree)
    else
        subtree:add(fields.data, buffer())
        pinfo.cols.info = "Unknown Livox Data"
    end
end

function dissect_control_frame(buffer, pinfo, subtree)
    local length = buffer:len()

    -- Header fields
    subtree:add_le(fields.sof, buffer(0,1))
    subtree:add_le(fields.version, buffer(1,1))
    local frame_length = buffer(2,2):le_uint()
    subtree:add_le(fields.length, buffer(2,2))
    subtree:add_le(fields.cmd_type, buffer(4,1))
    subtree:add_le(fields.seq_num, buffer(5,2))
    subtree:add_le(fields.crc16, buffer(7,2))

    -- Data section
    if length > 9 then
        local data_length = length - 13  -- Total - header - crc32
        if data_length > 0 then
            local data_tree = subtree:add(fields.data, buffer(9, data_length))
            dissect_command_data(buffer(9, data_length), pinfo, data_tree)
        end
    end

    -- CRC32
    if length >= 13 then
        subtree:add_le(fields.crc32, buffer(length-4, 4))
    end

    local cmd_type = buffer(4,1):uint()
    local cmd_type_str = ""
    if cmd_type == 0x00 then cmd_type_str = "CMD"
    elseif cmd_type == 0x01 then cmd_type_str = "ACK"
    elseif cmd_type == 0x02 then cmd_type_str = "MSG"
    end

    pinfo.cols.info = "Livox Control Frame [" .. cmd_type_str .. "]"
end

function dissect_command_data(buffer, pinfo, tree)
    local length = buffer:len()
    if length < 2 then return end

    local cmd_set = buffer(0,1):uint()
    local cmd_id = buffer(1,1):uint()

    tree:add_le(fields.cmd_set, buffer(0,1))
    tree:add_le(fields.cmd_id, buffer(1,1))

    if length > 2 then
        local cmd_data = buffer(2, length-2)
        local data_tree = tree:add(fields.cmd_data, cmd_data)

        -- Parse specific commands
        if cmd_set == 0x00 and cmd_id == 0x00 then
            -- Broadcast message
            if cmd_data:len() >= 19 then
                data_tree:add(fields.broadcast_code, cmd_data(0,16))
                data_tree:add_le(fields.dev_type, cmd_data(16,1))
            end
            pinfo.cols.info = "Livox Broadcast Message"
        elseif cmd_set == 0x00 and cmd_id == 0x01 then
            pinfo.cols.info = "Livox Handshake"
        elseif cmd_set == 0x00 and cmd_id == 0x03 then
            pinfo.cols.info = "Livox Heartbeat"
        elseif cmd_set == 0x00 and cmd_id == 0x04 then
            pinfo.cols.info = "Livox Start/Stop Sampling"
        else
            pinfo.cols.info = "Livox Command [" .. string.format("0x%02x:0x%02x", cmd_set, cmd_id) .. "]"
        end
    end
end

function dissect_point_cloud(buffer, pinfo, subtree)
    local length = buffer:len()
    if length < 18 then return end

    subtree:add_le(fields.pc_version, buffer(0,1))
    subtree:add_le(fields.slot_id, buffer(1,1))
    subtree:add_le(fields.lidar_id, buffer(2,1))
    subtree:add_le(fields.reserved, buffer(3,1))

    -- Status code with breakdown (check if bit operations are available)
    local status_code = buffer(4,4):le_uint()
    local status_tree = subtree:add_le(fields.status_code, buffer(4,4))

    -- Try to break down status code bits (may not work on all Wireshark versions)
    local success, temp_status = pcall(function() return bit.band(status_code, 0x03) end)
    if success then
        local volt_status = bit.band(bit.rshift(status_code, 2), 0x03)
        local motor_status = bit.band(bit.rshift(status_code, 4), 0x03)
        
        status_tree:add(fields.temp_status, temp_status)
        status_tree:add(fields.volt_status, volt_status)
        status_tree:add(fields.motor_status, motor_status)
    end

    subtree:add_le(fields.timestamp_type, buffer(8,1))
    subtree:add_le(fields.data_type, buffer(9,1))
    subtree:add_le(fields.timestamp, buffer(10,8))

    -- Point cloud data
    if length > 18 then
        local data_type = buffer(9,1):uint()
        local point_tree = subtree:add(fields.point_data, buffer(18, length-18))

        local type_str = ""
        if data_type == 0 then type_str = "Cartesian"
        elseif data_type == 1 then type_str = "Spherical"
        elseif data_type == 6 then type_str = "IMU"
        else type_str = "Unknown"
        end

        pinfo.cols.info = "Livox Point Cloud [" .. type_str .. "]"
    end
end

-- Register the protocol on standard ports
local udp_port = DissectorTable.get("udp.port")
udp_port:add(55000, livox_proto)  -- Broadcast port
udp_port:add(65000, livox_proto)  -- Control port

-- Also register on common data ports (you can add more as needed)
udp_port:add(56000, livox_proto)
udp_port:add(57000, livox_proto)
udp_port:add(58000, livox_proto)