Coverage for /home/martinb/.local/share/virtualenvs/camcops/lib/python3.6/site-packages/cryptography/hazmat/primitives/ciphers/algorithms.py : 69%

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1# This file is dual licensed under the terms of the Apache License, Version
2# 2.0, and the BSD License. See the LICENSE file in the root of this repository
3# for complete details.
6from cryptography import utils
7from cryptography.hazmat.primitives.ciphers import (
8 BlockCipherAlgorithm,
9 CipherAlgorithm,
10)
11from cryptography.hazmat.primitives.ciphers.modes import ModeWithNonce
14def _verify_key_size(algorithm: CipherAlgorithm, key: bytes):
15 # Verify that the key is instance of bytes
16 utils._check_byteslike("key", key)
18 # Verify that the key size matches the expected key size
19 if len(key) * 8 not in algorithm.key_sizes:
20 raise ValueError(
21 "Invalid key size ({}) for {}.".format(
22 len(key) * 8, algorithm.name
23 )
24 )
25 return key
28class AES(CipherAlgorithm, BlockCipherAlgorithm):
29 name = "AES"
30 block_size = 128
31 # 512 added to support AES-256-XTS, which uses 512-bit keys
32 key_sizes = frozenset([128, 192, 256, 512])
34 def __init__(self, key: bytes):
35 self.key = _verify_key_size(self, key)
37 @property
38 def key_size(self) -> int:
39 return len(self.key) * 8
42class Camellia(CipherAlgorithm, BlockCipherAlgorithm):
43 name = "camellia"
44 block_size = 128
45 key_sizes = frozenset([128, 192, 256])
47 def __init__(self, key: bytes):
48 self.key = _verify_key_size(self, key)
50 @property
51 def key_size(self) -> int:
52 return len(self.key) * 8
55class TripleDES(CipherAlgorithm, BlockCipherAlgorithm):
56 name = "3DES"
57 block_size = 64
58 key_sizes = frozenset([64, 128, 192])
60 def __init__(self, key: bytes):
61 if len(key) == 8:
62 key += key + key
63 elif len(key) == 16:
64 key += key[:8]
65 self.key = _verify_key_size(self, key)
67 @property
68 def key_size(self) -> int:
69 return len(self.key) * 8
72class Blowfish(CipherAlgorithm, BlockCipherAlgorithm):
73 name = "Blowfish"
74 block_size = 64
75 key_sizes = frozenset(range(32, 449, 8))
77 def __init__(self, key: bytes):
78 self.key = _verify_key_size(self, key)
80 @property
81 def key_size(self) -> int:
82 return len(self.key) * 8
85class CAST5(CipherAlgorithm, BlockCipherAlgorithm):
86 name = "CAST5"
87 block_size = 64
88 key_sizes = frozenset(range(40, 129, 8))
90 def __init__(self, key: bytes):
91 self.key = _verify_key_size(self, key)
93 @property
94 def key_size(self) -> int:
95 return len(self.key) * 8
98class ARC4(CipherAlgorithm):
99 name = "RC4"
100 key_sizes = frozenset([40, 56, 64, 80, 128, 160, 192, 256])
102 def __init__(self, key: bytes):
103 self.key = _verify_key_size(self, key)
105 @property
106 def key_size(self) -> int:
107 return len(self.key) * 8
110class IDEA(CipherAlgorithm):
111 name = "IDEA"
112 block_size = 64
113 key_sizes = frozenset([128])
115 def __init__(self, key: bytes):
116 self.key = _verify_key_size(self, key)
118 @property
119 def key_size(self) -> int:
120 return len(self.key) * 8
123class SEED(CipherAlgorithm, BlockCipherAlgorithm):
124 name = "SEED"
125 block_size = 128
126 key_sizes = frozenset([128])
128 def __init__(self, key: bytes):
129 self.key = _verify_key_size(self, key)
131 @property
132 def key_size(self) -> int:
133 return len(self.key) * 8
136class ChaCha20(CipherAlgorithm, ModeWithNonce):
137 name = "ChaCha20"
138 key_sizes = frozenset([256])
140 def __init__(self, key: bytes, nonce: bytes):
141 self.key = _verify_key_size(self, key)
142 utils._check_byteslike("nonce", nonce)
144 if len(nonce) != 16:
145 raise ValueError("nonce must be 128-bits (16 bytes)")
147 self._nonce = nonce
149 nonce = utils.read_only_property("_nonce")
151 @property
152 def key_size(self) -> int:
153 return len(self.key) * 8