Hey Garmin developer folks!
I notice that the Connect IQ SDK supports:
- AES256 encryption
- NIST P-256 ECDH key exchange
- SHA-256 hashing
- HMAC signatures
That's nice, but for some reason even though ECDH is supported, it doesn't seem to do ECDSA signatures or verification. I was wondering if this feature (obviously supported by the hardware already...) could be exposed through the SDK?
Or maybe there's some way I don't see to do point multiplication to compute a signature by pretending it's a key agreement? After all, ECDH is just multiplying one EC point by another, and that's also all the ECDSA signature operation is...