signature_utils.py 文件源码

def create_verifier_for_pss(signature, hash_method, public_key):
    """Create the verifier to use when the key type is RSA-PSS.

    :param signature: the decoded signature to use
    :param hash_method: the hash method to use, as a cryptography object
    :param public_key: the public key to use, as a cryptography object
    :raises: SignatureVerificationError if the RSA-PSS specific properties
                                        are invalid
    :returns: the verifier to use to verify the signature for RSA-PSS
    """
    # default to MGF1
    mgf = padding.MGF1(hash_method)

    # default to max salt length
    salt_length = padding.PSS.MAX_LENGTH

    # return the verifier
    return public_key.verifier(
        signature,
        padding.PSS(mgf=mgf, salt_length=salt_length),
        hash_method
    )