ECDSA with self defined key

[MLai]

Hi all,

I am working on a ble5 beacon with ecdsa signature. I would like to use mobile to verify my message. As I see that the crypto ecdsa example use raw key and generate the ecdsa key again, I would like to know is there any way to use the key that I already generated for ecdsa, i.e. using openssl, in the programme, as I see the sign step need to use  nrf_crypto_ecc_private_key_t. If not, is there anyway to generate it using nrfutil, as I need the pem file of public key to verify the signature. Thanks

Best regards,

MLai

[Einar Thorsrud]

Hi MLai,

The nrf_crypto library can only import and export raw keys, and not certificates (like .pem files). So you can use the private key you have allready generated, but you need to export it to raw using some tool of your choice, and then import it to nrf_crypto using nrf_crypto_ecc_private_key_from_raw().

[MLai]

Hi Einar,

I am now testing on the key generated from both openssl and nrfutil, but I am facing the problem in this thread. And I am a little bit confuse that the hash generated is in what format, is it (r|s) or in other format, as I see normally the hash are in base 64 format which should more than 64 bytes. Thanks a lot.

Best regards,

MLai

[Einar Thorsrud]

Hi MLai,

The raw key which is used in the nrf_crypto APIs is raw hex, not base 64 format. (There are no nrf_crypto API's that wark on base 64.)