%PDF- %PDF-
Direktori : /lib64/python3.6/site-packages/cryptography/hazmat/primitives/ciphers/ |
Current File : //lib64/python3.6/site-packages/cryptography/hazmat/primitives/ciphers/algorithms.py |
# 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 absolute_import, division, print_function from cryptography import utils from cryptography.hazmat.primitives.ciphers import ( BlockCipherAlgorithm, CipherAlgorithm, ) from cryptography.hazmat.primitives.ciphers.modes import ModeWithNonce def _verify_key_size(algorithm, key): # 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( "Invalid key size ({}) for {}.".format( len(key) * 8, algorithm.name ) ) return key @utils.register_interface(BlockCipherAlgorithm) @utils.register_interface(CipherAlgorithm) class AES(object): name = "AES" block_size = 128 # 512 added to support AES-256-XTS, which uses 512-bit keys key_sizes = frozenset([128, 192, 256, 512]) def __init__(self, key): self.key = _verify_key_size(self, key) @property def key_size(self): return len(self.key) * 8 @utils.register_interface(BlockCipherAlgorithm) @utils.register_interface(CipherAlgorithm) class Camellia(object): name = "camellia" block_size = 128 key_sizes = frozenset([128, 192, 256]) def __init__(self, key): self.key = _verify_key_size(self, key) @property def key_size(self): return len(self.key) * 8 @utils.register_interface(BlockCipherAlgorithm) @utils.register_interface(CipherAlgorithm) class TripleDES(object): name = "3DES" block_size = 64 key_sizes = frozenset([64, 128, 192]) def __init__(self, key): if len(key) == 8: key += key + key elif len(key) == 16: key += key[:8] self.key = _verify_key_size(self, key) @property def key_size(self): return len(self.key) * 8 @utils.register_interface(BlockCipherAlgorithm) @utils.register_interface(CipherAlgorithm) class Blowfish(object): name = "Blowfish" block_size = 64 key_sizes = frozenset(range(32, 449, 8)) def __init__(self, key): self.key = _verify_key_size(self, key) @property def key_size(self): return len(self.key) * 8 @utils.register_interface(BlockCipherAlgorithm) @utils.register_interface(CipherAlgorithm) class CAST5(object): name = "CAST5" block_size = 64 key_sizes = frozenset(range(40, 129, 8)) def __init__(self, key): self.key = _verify_key_size(self, key) @property def key_size(self): return len(self.key) * 8 @utils.register_interface(CipherAlgorithm) class ARC4(object): name = "RC4" key_sizes = frozenset([40, 56, 64, 80, 128, 160, 192, 256]) def __init__(self, key): self.key = _verify_key_size(self, key) @property def key_size(self): return len(self.key) * 8 @utils.register_interface(CipherAlgorithm) class IDEA(object): name = "IDEA" block_size = 64 key_sizes = frozenset([128]) def __init__(self, key): self.key = _verify_key_size(self, key) @property def key_size(self): return len(self.key) * 8 @utils.register_interface(BlockCipherAlgorithm) @utils.register_interface(CipherAlgorithm) class SEED(object): name = "SEED" block_size = 128 key_sizes = frozenset([128]) def __init__(self, key): self.key = _verify_key_size(self, key) @property def key_size(self): return len(self.key) * 8 @utils.register_interface(CipherAlgorithm) @utils.register_interface(ModeWithNonce) class ChaCha20(object): name = "ChaCha20" key_sizes = frozenset([256]) def __init__(self, key, nonce): self.key = _verify_key_size(self, key) utils._check_byteslike("nonce", nonce) if len(nonce) != 16: raise ValueError("nonce must be 128-bits (16 bytes)") self._nonce = nonce nonce = utils.read_only_property("_nonce") @property def key_size(self): return len(self.key) * 8