FOTA upgrade MCUboot image with new signing key and app image simultaneously?

RE: FOTA upgrade MCUboot image with new signing key and app image simultaneously?

Vidar Berg — Fri, 11 Apr 2025 12:10:40 GMT

Yes, your understanding is correct. Therefore it is important that the private key is kept securely stored (on signing server, etc.) Only the public key will be embedded in the MCUBoot FW image.

RE: FOTA upgrade MCUboot image with new signing key and app image simultaneously?

jeremy.olson — Fri, 11 Apr 2025 11:01:24 GMT

Alright, so that means that MCUboot is effectively not updatable with a new firmware signing key for new application firmware with the current implementation of the aws_fota and fota_download (and also likely the mcuboot implementation) libraries. Do I understand correctly?

RE: FOTA upgrade MCUboot image with new signing key and app image simultaneously?

Vidar Berg — Fri, 11 Apr 2025 09:16:18 GMT

Sorry for the delay. By updating both the application and MCUboot simultaneously as discussed in the linked ticket you would be able to update the public key in the bootloader. Unfortunately, simultaneous update of these two images is not supported in the current implementation/design.

RE: FOTA upgrade MCUboot image with new signing key and app image simultaneously?

jeremy.olson — Fri, 11 Apr 2025 07:54:43 GMT

I saw an engineer was assigned to this post in the last two days. Any movement on this?