NewEcdsaSha256Signer parses given key and creates EcdsaSha256Signer.

NewEcdsaSha256Verifier parses given certificate and creates EcdsaSha256Verifier.

EcdsaSha256Signer is the signer implementation of ECDSA-SHA256.

EcdsaSha256Verifier is the verifier implementation of ECDSA-SHA256.

Signer defines an interface to sign messages.

Verifier defines an interface to verify if the message and the signature are matched.