feature-firmware/org.meshtastic.feature.firmware.ota.dfu/SecureDfuTransport

SecureDfuTransport

class SecureDfuTransport(scanner: BleScanner, connectionFactory: BleConnectionFactory, address: String, dispatcher: CoroutineDispatcher) : DfuUploadTransport(source)

Kable-based transport for the Nordic Secure DFU (Secure DFU over BLE) protocol.

Usage:

triggerButtonlessDfu — connect to the device in normal mode and trigger reboot into DFU mode.
connectToDfuMode — scan for the device in DFU mode and establish the DFU GATT session.
transferInitPacket / transferFirmware — send .dat then .bin.
abort — send ABORT to the device before closing (on cancellation or error).
close — tear down the connection.

Constructors

SecureDfuTransport

constructor(scanner: BleScanner, connectionFactory: BleConnectionFactory, address: String, dispatcher: CoroutineDispatcher)

Types

Companion

object Companion

Properties

isLowSpeedTransfer

open val isLowSpeedTransfer: Boolean

True once connected if the bootloader can only transfer in small (≤20-byte) blocks — i.e. it did not negotiate a larger ATT MTU. Used to surface a "slow bootloader" advisory to the user. Valid after connectToDfuMode.

Functions

abort

open suspend override fun abort()

Sends the ABORT opcode to the device, instructing it to discard any in-progress transfer and return to an idle state. Best-effort — never throws.

open suspend override fun close()

Disconnect from the DFU target and cancel the transport coroutine scope.

connectToDfuMode

open suspend override fun connectToDfuMode(): Result<Unit>

Scans for the device in DFU mode (address or address+1) and establishes the GATT connection, enabling notifications on the Control Point.

transferFirmware

open suspend override fun transferFirmware(firmware: ByteArray, onProgress: suspend (Float) -> Unit): Result<Unit>

Sends the firmware binary (.bin file) using the DFU object-transfer protocol.

transferInitPacket

open suspend override fun transferInitPacket(initPacket: ByteArray): Result<Unit>

Sends the DFU init packet (.dat file). The device verifies this against the bootloader's security requirements before accepting firmware.

triggerButtonlessDfu

suspend fun triggerButtonlessDfu(): Result<Unit>

Connects to the device running normal firmware and writes to the Buttonless DFU characteristic so the bootloader takes over. The device disconnects and reboots.