nrf patch needs fails

[Rob-Grady]

First, thanks for all the work here, it's been really helpful.

I've been working with samples_for_nrf_connect_sdk/bootloader_samples/keys_and_signatures/mcuboot_smp_encryption. I got the code running, thanks for that. But the patch file (nrf.patch) does not work. I applied it, but the output it produced would not boot. It wasn't clear to me which sdk that patch should be applied to. Could you possibly update the patch for sdk 2.6 or 2.7?

Thanks,

Rob Grady

[Rob-Grady]

Or provide a copy of the results (the entire file) you get after the patch was applied.

[hellesvik-nordic]

Yea this sample was added before sysbuild. For v2.8.0, I think maybe the nRF Connect SDK supports encrypted directly. I see that Migrating from multi-image builds to sysbuild mentions SB_CONFIG_BOOT_ENCRYPTION. Try to enable this with sysbuild and see if you are able to encrypt your images that way instead of using this sample.

I plan to update this sample to the above method eventually, when I got time.

[Rob-Grady]

So I am using sysbuild, and you are right Nordic does support some level of encryption. Even though they officially do not support it, sysbuild will generate zephyr.encrypted.signed.bin files. The problem seems to be with the 'merge' step, where the bootloader (mcuboot) and the app image are merged into one file. sysbuild is selecting the wrong files to merge. It should be mcuboot.hex and app.signed.hex. I think it might be selecting app.encrypted.signed.hex, which fails to boot. I work around the issue by programming the correct files separately using the Nordic programmer tool.

[hellesvik-nordic]

Thanks for the report! I have forwarded it to our devs, so they will investigate this further.