DFU Bootloader with micro-ecc in the nRF52840

[WesC]

Reviewing the table in the SDK 17.0.2 documentation for Crypto Backends

https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.2/nrf_crypto_default_backends.html

it looks like the only option for DFU Bootloader for the nRF52840 is CC310_bl.  All other IC's it is the Micro_ECC default

1. I am have problems with this detail of the table because examination of the ’840 .emProject file for the Secure Bootloader seems to show support for Oberon, as shown by these file inclusions:
   1. “nRF Crypto backend Oberon”,
   2. “nRF Oberon Crypto”.
2. Because the context of the table is to show you the compatibility of Nordic examples with micro-ecc, what am I going to have to do to run micro-ecc on the ‘840?
3. Some of the supported bootloader functionality is not present in the source code and support files. For example, Bonds are turned off in sdk_config.h for the ‘840 DK.
4. What code support has to be added for bond support in the secure bootloader?

[Marjeris Romero]

Hi,

Please see 'Enabling micro-ecc support in selected examples' for how to run micro-ecc on the nRF52840 and support Oberon.

Regarding your last two question, I think these are answered in this Devzone blogpost.

Best regards,

Marjeris

[WesC]

So is the Table incorrect and you can use micro-ecc or oberon with Bootloader?

ALso, your second link was pointing to the infocenter for Micro-ecc.  Can you share the link to the devzone blogpost

[Marjeris Romero]

Hi,

I am sorry, I have updated the link for the Devzone post, and posting it here as well: https://devzone.nordicsemi.com/nordic/short-range-guides/b/software-development-kit/posts/getting-started-with-nordics-secure-dfu-bootloader#h98sjziax1zv1yon27f19upb8g1nbw0f0

The table explains which of the nrf_crypto backends are default configured by the different examples, but you can change the nrf_crypto backend as explained in: https://infocenter.nordicsemi.com/index.jsp?topic=%2Fsdk_nrf5_v17.0.2%2Flib_crypto_config.html

[WesC]

Thank you for the reply.

I guess we need to update the chart.  I would assume the Red X means that it is not supported.  because the green check means it is, but not but default.  That is why i am confused.

Thanks again

wes

[Marjeris Romero]

Hi wes,

Perhaps it's not so well explained but I think it's suppose to be explained here:

"X" will then mean that (minor) modification to the example is needed in order to add support for this backend. In the case of Oberon, it will work with the DFU bootloader (we have customers implementing it), the only limitation may be the flash memory, it looks like you will need to increase the flash size of the bootloader if the customer is planning to use Oberon. I have forwarded an email explaining this to you.

Best regards,

Marjeris