pub fn decode_p256_pkcs8_der(der: &[u8]) -> Result<SecretKey, Pkcs8Error>Expand description
Decodes a P-256 secret key from PKCS#8 DER in the fixed 138-byte
PrivateKeyInfo template produced by encode_p256_pkcs8_der.
The embedded public key is checked against the one derived from the private scalar.
Returns Pkcs8Error when the input is not exactly the expected
template, when the private scalar is invalid, or when the embedded
public key does not correspond to the private key
(Pkcs8Error::InvalidPublicKeyMismatch).