Secure Boot Planning
Establish a vendor-supported chain of trust from immutable boot code to signed application images.
Arduino-compatible frameworks, ESP-IDF/FreeRTOS, PIC/AVR/STM32/RP-class systems; apply exact vendor documentation for the selected MCU.Architecture
Root public-key digest → verified bootloader → verified partition/image → trusted application.
Security and recovery risks
- Never upload private signing keys to WordPress or source control.nFuse/eFuse operations can be irreversible.nPreserve a tested recovery/service strategy before production.
Implementation procedure
- Identify exact MCU revision and secure-boot scheme.nCreate offline development and production key procedures.nVerify signed images on disposable development hardware.nTest unsigned/tampered rejection and recovery.nUse controlled manufacturing authorization for irreversible enablement.
Starter code / configuration
Pseudocode: verify_signature(image, trusted_public_key_digest);Verification evidence
| Test | Expected | Evidence |
|---|---|---|
| Nominal boot | Correct version and hardware revision reported | Captured boot log |
| Fault recovery | Defined safe state and reset reason | Fault-injection record |
| Power cycle | No corrupt configuration or unsafe output | Repeated-cycle log |
Required release artifacts
- Versioned firmware binary and SHA-256
- Source revision / build identifier
- Board and hardware-revision compatibility list
- Test report and known limitations
- Recovery image and factory-reset procedure
- Provisioning/calibration schema
- Release approval record
Local browser tools
Firmware production workbench
A/B update exercise
OTA and automatic rollback simulator
Advance one validated stage at a time. A failed boot test returns the device to the previous slot.
- Running confirmed firmware from Slot A.
Release gate
Production-readiness checklist
A downloadable release decision is generated only after every mandatory control is confirmed.