SBSFU and Firmware Encryption

[RKher.1]

I'm currently investigating SBSFU options for STM32 and it seems like the base package incorporates authentication of the firmware based on on digital signatures (ECDSA, edDSA etc.) but does not incorporate firmware encryption. I have an additional requirement to encrypt the firmware prior to flashing it to the device and then decrypting and authenticating the app image prior to execution. Is this possible through the base SBSFU package or does it require a custom extension/implementation? Thanks!

[Bubbles]

Hello @RKher.1​ ,

normally the SBSFU example includes firmware encryption using AES.

Check AN5056 again for details. You can normally choose another cryptographic scheme (see figure 15 in the AN) or another cryptographic library.

BR,

J

[RKher.1]

Thanks once again @JHOUD​