Is there a way to encrypt the bootloader?

RE: Is there a way to encrypt the bootloader?

Sigurd — Thu, 24 Aug 2023 14:38:22 GMT

Maybe it's possible to use the ECB driver/HAL functions instead of the SoftDevice ecb API.

RE: Is there a way to encrypt the bootloader?

Lurn_Z — Thu, 24 Aug 2023 08:59:52 GMT

yes, I found this. Since I didn't use the softdevice, maybe this is not suitable for my case.

Do you have any other way to achieve it? For example, use a unique identification code to do operations like activation?

RE: Is there a way to encrypt the bootloader?

Sigurd — Thu, 24 Aug 2023 08:51:44 GMT

[quote user="Lurn_Z"]Does this solution work for non-softdevice?[/quote]

Looking briefly through the code in the post, I see that e.g. nrf_dfu_validation_crypt() uses sd_ecb_block_encrypt() function, so it seems to depend on SoftDevice.

RE: Is there a way to encrypt the bootloader?

Lurn_Z — Thu, 24 Aug 2023 05:42:31 GMT

Hi,

Does this solution work for non-softdevice?

Because when I modify the bootloader I found that some function was declared in softdevice.

RE: Is there a way to encrypt the bootloader?

Sigurd — Tue, 22 Aug 2023 12:34:39 GMT

The post is a few years old, so you might want to try with an older version of nrfutil.

RE: Is there a way to encrypt the bootloader?

Lurn_Z — Tue, 22 Aug 2023 10:29:13 GMT

Hi Sigurd,

Not sure where the problem is, but I modified nrfutil according to what was said in the case, but I didn't get the result as said in the case.

So I have not continued down to the following operation.

Get errors like

I check the code, since my nrfutil version is higher than the case, so I didn't replace the code, just add the nonce things in the code.

I also used the nrfutil.exe provided in the case, it can get a random value.

can you tell me what's wrong?

Note:

I think my nrfutil version is 6.17.

Best regards

Lurn

RE: Is there a way to encrypt the bootloader?

Lurn_Z — Tue, 22 Aug 2023 08:55:02 GMT

Hi Sigurd,

Thanks for your reply, I will try to learn it.

Best regards,

Lurn

RE: Is there a way to encrypt the bootloader?

Sigurd — Tue, 22 Aug 2023 08:49:56 GMT

Hi,

There is no official support for encrypted secure DFU in the nRF5-SDK. However, a user have implemented this, and provided a guide on how it can be done here: Adding Encryption to Secure DFU SDK v15

Disclaimer: This 3rd party guide has not been tested by Nordic, so there might be unknown issues. It is hence provided by this 3rd party as-is, without any warranty.