1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
|
# 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
import binascii
import pytest
from cryptography.exceptions import (
AlreadyFinalized,
InvalidSignature,
_Reasons,
)
from cryptography.hazmat.backends.interfaces import CMACBackend
from cryptography.hazmat.primitives.ciphers.algorithms import (
AES,
ARC4,
TripleDES,
)
from cryptography.hazmat.primitives.cmac import CMAC
from ...utils import (
load_nist_vectors,
load_vectors_from_file,
raises_unsupported_algorithm,
)
vectors_aes128 = load_vectors_from_file(
"CMAC/nist-800-38b-aes128.txt", load_nist_vectors
)
vectors_aes192 = load_vectors_from_file(
"CMAC/nist-800-38b-aes192.txt", load_nist_vectors
)
vectors_aes256 = load_vectors_from_file(
"CMAC/nist-800-38b-aes256.txt", load_nist_vectors
)
vectors_aes = vectors_aes128 + vectors_aes192 + vectors_aes256
vectors_3des = load_vectors_from_file(
"CMAC/nist-800-38b-3des.txt", load_nist_vectors
)
fake_key = b"\x00" * 16
@pytest.mark.requires_backend_interface(interface=CMACBackend)
class TestCMAC(object):
@pytest.mark.supported(
only_if=lambda backend: backend.cmac_algorithm_supported(
AES(fake_key)
),
skip_message="Does not support CMAC.",
)
@pytest.mark.parametrize("params", vectors_aes)
def test_aes_generate(self, backend, params):
key = params["key"]
message = params["message"]
output = params["output"]
cmac = CMAC(AES(binascii.unhexlify(key)), backend)
cmac.update(binascii.unhexlify(message))
assert binascii.hexlify(cmac.finalize()) == output
@pytest.mark.supported(
only_if=lambda backend: backend.cmac_algorithm_supported(
AES(fake_key)
),
skip_message="Does not support CMAC.",
)
@pytest.mark.parametrize("params", vectors_aes)
def test_aes_verify(self, backend, params):
key = params["key"]
message = params["message"]
output = params["output"]
cmac = CMAC(AES(binascii.unhexlify(key)), backend)
cmac.update(binascii.unhexlify(message))
assert cmac.verify(binascii.unhexlify(output)) is None
@pytest.mark.supported(
only_if=lambda backend: backend.cmac_algorithm_supported(
TripleDES(fake_key)
),
skip_message="Does not support CMAC.",
)
@pytest.mark.parametrize("params", vectors_3des)
def test_3des_generate(self, backend, params):
key1 = params["key1"]
key2 = params["key2"]
key3 = params["key3"]
key = key1 + key2 + key3
message = params["message"]
output = params["output"]
cmac = CMAC(TripleDES(binascii.unhexlify(key)), backend)
cmac.update(binascii.unhexlify(message))
assert binascii.hexlify(cmac.finalize()) == output
@pytest.mark.supported(
only_if=lambda backend: backend.cmac_algorithm_supported(
TripleDES(fake_key)
),
skip_message="Does not support CMAC.",
)
@pytest.mark.parametrize("params", vectors_3des)
def test_3des_verify(self, backend, params):
key1 = params["key1"]
key2 = params["key2"]
key3 = params["key3"]
key = key1 + key2 + key3
message = params["message"]
output = params["output"]
cmac = CMAC(TripleDES(binascii.unhexlify(key)), backend)
cmac.update(binascii.unhexlify(message))
assert cmac.verify(binascii.unhexlify(output)) is None
@pytest.mark.supported(
only_if=lambda backend: backend.cmac_algorithm_supported(
AES(fake_key)
),
skip_message="Does not support CMAC.",
)
def test_invalid_verify(self, backend):
key = b"2b7e151628aed2a6abf7158809cf4f3c"
cmac = CMAC(AES(key), backend)
cmac.update(b"6bc1bee22e409f96e93d7e117393172a")
with pytest.raises(InvalidSignature):
cmac.verify(b"foobar")
@pytest.mark.supported(
only_if=lambda backend: backend.cipher_supported(ARC4(fake_key), None),
skip_message="Does not support CMAC.",
)
def test_invalid_algorithm(self, backend):
key = b"0102030405"
with pytest.raises(TypeError):
CMAC(ARC4(key), backend)
@pytest.mark.supported(
only_if=lambda backend: backend.cmac_algorithm_supported(
AES(fake_key)
),
skip_message="Does not support CMAC.",
)
def test_raises_after_finalize(self, backend):
key = b"2b7e151628aed2a6abf7158809cf4f3c"
cmac = CMAC(AES(key), backend)
cmac.finalize()
with pytest.raises(AlreadyFinalized):
cmac.update(b"foo")
with pytest.raises(AlreadyFinalized):
cmac.copy()
with pytest.raises(AlreadyFinalized):
cmac.finalize()
with pytest.raises(AlreadyFinalized):
cmac.verify(b"")
@pytest.mark.supported(
only_if=lambda backend: backend.cmac_algorithm_supported(
AES(fake_key)
),
skip_message="Does not support CMAC.",
)
def test_verify_reject_unicode(self, backend):
key = b"2b7e151628aed2a6abf7158809cf4f3c"
cmac = CMAC(AES(key), backend)
with pytest.raises(TypeError):
cmac.update(u"")
with pytest.raises(TypeError):
cmac.verify(u"")
@pytest.mark.supported(
only_if=lambda backend: backend.cmac_algorithm_supported(
AES(fake_key)
),
skip_message="Does not support CMAC.",
)
def test_copy_with_backend(self, backend):
key = b"2b7e151628aed2a6abf7158809cf4f3c"
cmac = CMAC(AES(key), backend)
cmac.update(b"6bc1bee22e409f96e93d7e117393172a")
copy_cmac = cmac.copy()
assert cmac.finalize() == copy_cmac.finalize()
@pytest.mark.supported(
only_if=lambda backend: backend.cmac_algorithm_supported(
AES(fake_key)
),
skip_message="Does not support CMAC.",
)
def test_buffer_protocol(self, backend):
key = bytearray(b"2b7e151628aed2a6abf7158809cf4f3c")
cmac = CMAC(AES(key), backend)
cmac.update(b"6bc1bee22e409f96e93d7e117393172a")
assert cmac.finalize() == binascii.unhexlify(
b"a21e6e647bfeaf5ca0a5e1bcd957dfad"
)
def test_invalid_backend():
key = b"2b7e151628aed2a6abf7158809cf4f3c"
pretend_backend = object()
with raises_unsupported_algorithm(_Reasons.BACKEND_MISSING_INTERFACE):
CMAC(AES(key), pretend_backend)
|
