How to Convert RSA keys from .pem to .der and vice versa by using psa in nrf52840

RE: How to Convert RSA keys from .pem to .der and vice versa by using psa in nrf52840

Einar Thorsrud — Thu, 20 Feb 2025 09:00:15 GMT

Hi,

I have checked this a bi tmore, and this is unfortunately far from staright-forward. If possible, it would be better and much simpler to do conversion to/from PEM externally and only import raw keys to the nRF (and the same if you need to export keys).

For instance, if you have a private key in PEM format, you can convert it to a raw key like this using openssl:

openssl rsa -inform PEM -outform DER -in <infilename> -out <outfilename>

RE: How to Convert RSA keys from .pem to .der and vice versa by using psa in nrf52840

Sakshi_0806 — Mon, 17 Feb 2025 06:48:32 GMT

Hello,

I am using "mbedtls_pk_parse_public_key" function and then "mbedtls_pk_write_pubkey_der" this function but how can i enable these two function definition in my target? by enabling which macro we can do that?

RE: How to Convert RSA keys from .pem to .der and vice versa by using psa in nrf52840

Einar Thorsrud — Thu, 13 Feb 2025 14:49:37 GMT

Hi,

Do you need to do it on target, or can you do it using openssl x509 or similar? On target, it could be done using mbedtls_pk_parse_key() and then mbedtls_pk_import_into_psa() for newer SDK versions, but not 2.6 (as described here).