MCUBoot Over-the-Air Download (OAD)

The following sections aim to describe the lower layers of OAD software that are common across all protocol stack implementations. This includes the OAD image header, the flash layout, Secure Bootloader, and the oad image tool.

Warning

The BLE-Stack OAD Profile does not implement or perform any security or authentication mechanisms as part of the firmware update process. System developers should take measures to adequately authenticate peer devices and only accept and/or apply firmware images transferred from trusted sources via the OAD Profile. TI recommends applications use Bluetooth LE Secure Connections (LESC) with Man-in-the-Middle (MITM) protection with peer devices when performing wireless firmware updates, although the use of the LESC feature does not itself guarantee image authenticity.

When using the Secure OAD feature along with recommended parameters, firmware images are authenticated on the device using ECDSA signature validation algorithms to ensure image authenticity prior to updating the running firmware image. Just as with the OAD Profile, TI recommends applications use Bluetooth LE Secure Connections with Man-in-the-Middle (MITM) protection with peer devices when performing wireless firmware updates.

Attention

Currently the BLE5-Stack does not support off-chip OAD yet.

• Introduction
  • OAD Topology Overview
• OAD Storage & Security
  • OAD Storage
  • OAD Security
• MCUboot Overview
• MCUBoot for On-Chip OAD (Stack Library)
• MCUBoot OAD Image Header
  • MCUBoot OAD Image Header
• Flash Layout for On-Chip OAD
  • Constraints and Requirements for On-chip OAD (stack library)
  • Internal Flash Memory Layout
• Post-Build Script imgtool

The following sections aim to describe the BLE5-Stack specific application and profile layer of the OAD solution. The OAD application section will describe the BLE OAD process from a high level in terms of events and states, and the profile section will cover the actual structures that are sent over the air.

• OAD Application
  • OAD Software Architecture
  • OAD State Machine
    • Image Validation
    • Image Block Transfers
    • Completion of the OAD Process
• BLE-Stack OAD Profile
  • Over the Air Message Sequence
  • OAD Service (0xFFC0)
    • OAD Image Identify (0xFFC1)
    • OAD Image Block Characteristic (0xFFC2)
    • OAD Control Point Characteristic (0xFFC5)
      • Get OAD Block Size CMD/RSP
      • Set Image Count CMD/RSP
      • Start OAD CMD/RSP
      • Enable OAD Image CMD/RSP
      • Cancel OAD CMD/RSP
      • Disable OAD Image Block Write CMD/RSP
      • Get Software Version CMD/RSP
      • Get OAD Image Status CMD/RSP
      • Get Profile Version CMD/RSP
      • Get Device Type CMD/RSP
      • Image Block Write Char RSP
  • OAD Reset Service (0xFFD0)
    • OAD Start/Reset Characteristic (0xFFD1)
  • OAD Return Values
  • OAD Block Size Rules