Signature Scheme Implementation for nrf52 series

RE: Signature Scheme Implementation for nrf52 series

Einar Thorsrud — Thu, 09 Jan 2025 13:24:35 GMT

Hi Alessandro,

I would recomend looking at PSA APIs instead of mbed TLS, as that is what we are supporting going forward, and this is paritcularily relevant if you want to use the nRF54 series devices (you can use mbedTLS / legacy crypto there as well for now, but without hardwrae acceleration). That said, you can find infomration about using mbed TLS with nRF Connect SDK under Legacy crypto support, as for APIs, you should refer to the mbedTLS documentation or generic examples, as most is not nRF specific.

regardign integrating libraries in the SDK, the simplest if it is just a bunch of files, could be to include it directly in the application folder as just a part of the application. You can still keep it in a separate folder, but modify the CMakeLists.txt file to include that folder as well. You can also have a look at this sample of addding an external library (this demonstrate a library with a different build system, but that does not have to be the case). Or you can look at how various libraries are added in the SDK.

RE: Signature Scheme Implementation for nrf52 series

alebldn — Wed, 08 Jan 2025 13:55:42 GMT

Hi Einar, thanks for your response!

I'm familiar with the examples you provided: in fact, I've been using one of these to leverage high-level APIs to interact with security modules. Unfortunately, if I had to implement things myself I'd have to hack into the lower levels to employ the finite field arithmetic libraries employed by other signature schemes included in the crypto examples you provided. Do you have any suggestions about where could I find more about lower level libraries like mbed_tls? The official site doesn't really provide much information...

Other than that, aside the familiarity with specific libraries, are you aware of any guide that could help me integrate libraries that need to be built with CMake (similarly to our projects) into the nrf Connect SDK environment?

Thank you in advance,

Alessandro

RE: Signature Scheme Implementation for nrf52 series

Einar Thorsrud — Wed, 08 Jan 2025 13:47:02 GMT

Hi Alessandro,

I am not familiar with relic or libbbs so I do not have any specific input on that. It seems to me that it is purely software based though, so even if you port it successfully to the nRF you would not benefit from the CryptoCell CC310 crypto accelerator on the nRF52840.

For using the crypto accelerator and for future-proofing for other nRF devices, I suggest you look at implementing it using PSA crypto APIs. There are several crytpo examples you may find relevant in the SDK, including ECC samples.