validation.py 文件源码

def validate(self, bucket, key, public_key, digest_data, inflated_digest):
        """Validates a digest file.

        Throws a DigestError when the digest is invalid.

        :param bucket: Bucket of the digest file
        :param key: Key of the digest file
        :param public_key: Public key bytes.
        :param digest_data: Dict of digest data returned when JSON
            decoding a manifest.
        :param inflated_digest: Inflated digest file contents as bytes.
        """
        try:
            decoded_key = base64.b64decode(public_key)
            public_key = rsa.PublicKey.load_pkcs1(decoded_key, format='DER')
            to_sign = self._create_string_to_sign(digest_data, inflated_digest)
            signature_bytes = binascii.unhexlify(digest_data['_signature'])
            rsa.verify(to_sign, signature_bytes, public_key)
        except PyAsn1Error:
            raise DigestError(
                ('Digest file\ts3://%s/%s\tINVALID: Unable to load PKCS #1 key'
                 ' with fingerprint %s')
                % (bucket, key, digest_data['digestPublicKeyFingerprint']))
        except rsa.pkcs1.VerificationError:
            # Note from the Python-RSA docs: Never display the stack trace of
            # a rsa.pkcs1.VerificationError exception. It shows where in the
            # code the exception occurred, and thus leaks information about
            # the key.
            raise DigestSignatureError(bucket, key)