ÿØÿàJFIFÿþ ÿÛC       ÿÛC ÿÀÿÄÿÄ"#QrÿÄÿÄ&1!A"2qQaáÿÚ ?Øy,æ/3JæݹÈ߲؋5êXw²±ÉyˆR”¾I0ó2—PI¾IÌÚiMö¯–þrìN&"KgX:Šíµ•nTJnLK„…@!‰-ý ùúmë;ºgµŒ&ó±hw’¯Õ@”Ü— 9ñ-ë.²1<yà‚¹ïQÐU„ہ?.’¦èûbß±©Ö«Âw*VŒ) `$‰bØԟ’ëXÖ-ËTÜíGÚ3ð«g Ÿ§¯—Jx„–’U/ÂÅv_s(Hÿ@TñJÑãõçn­‚!ÈgfbÓc­:él[ðQe 9ÀPLbÃãCµm[5¿ç'ªjglå‡Ûí_§Úõl-;"PkÞÞÁQâ¼_Ñ^¢SŸx?"¸¦ùY騐ÒOÈ q’`~~ÚtËU¹CڒêV  I1Áß_ÿÙ# This file is dual licensed under the terms of the Apache License, Version # 2.0, and the BSD License. See the LICENSE file in the root of this repository # for complete details. from __future__ import annotations import abc from cryptography import utils # This exists to break an import cycle. It is normally accessible from the # ciphers module. class CipherAlgorithm(metaclass=abc.ABCMeta): @property @abc.abstractmethod def name(self) -> str: """ A string naming this mode (e.g. "AES", "Camellia"). """ @property @abc.abstractmethod def key_sizes(self) -> frozenset[int]: """ Valid key sizes for this algorithm in bits """ @property @abc.abstractmethod def key_size(self) -> int: """ The size of the key being used as an integer in bits (e.g. 128, 256). """ class BlockCipherAlgorithm(CipherAlgorithm): key: bytes @property @abc.abstractmethod def block_size(self) -> int: """ The size of a block as an integer in bits (e.g. 64, 128). """ def _verify_key_size(algorithm: CipherAlgorithm, key: bytes) -> bytes: # Verify that the key is instance of bytes utils._check_byteslike("key", key) # Verify that the key size matches the expected key size if len(key) * 8 not in algorithm.key_sizes: raise ValueError( f"Invalid key size ({len(key) * 8}) for {algorithm.name}." ) return key