aboutsummaryrefslogtreecommitdiffstats
path: root/tests/hazmat/primitives/test_hkdf.py
blob: e3e2a9df49c5a7c56fa522d886d54143e495203d (plain)
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
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
# implied.
# See the License for the specific language governing permissions and
# limitations under the License.

from __future__ import absolute_import, division, print_function

import six

import pytest

from cryptography.exceptions import AlreadyFinalized, InvalidKey
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.kdf.hkdf import HKDF


@pytest.mark.hmac
class TestHKDF(object):
    def test_length_limit(self, backend):
        big_length = 255 * (hashes.SHA256().digest_size // 8) + 1

        with pytest.raises(ValueError):
            HKDF(
                hashes.SHA256(),
                big_length,
                salt=None,
                info=None,
                backend=backend
            )

    def test_already_finalized(self, backend):
        hkdf = HKDF(
            hashes.SHA256(),
            16,
            salt=None,
            info=None,
            backend=backend
        )

        hkdf.derive(b"\x01" * 16)

        with pytest.raises(AlreadyFinalized):
            hkdf.derive(b"\x02" * 16)

        hkdf = HKDF(
            hashes.SHA256(),
            16,
            salt=None,
            info=None,
            backend=backend
        )

        hkdf.verify(b"\x01" * 16, b"gJ\xfb{\xb1Oi\xc5sMC\xb7\xe4@\xf7u")

        with pytest.raises(AlreadyFinalized):
            hkdf.verify(b"\x02" * 16, b"gJ\xfb{\xb1Oi\xc5sMC\xb7\xe4@\xf7u")

        hkdf = HKDF(
            hashes.SHA256(),
            16,
            salt=None,
            info=None,
            backend=backend
        )

    def test_verify(self, backend):
        hkdf = HKDF(
            hashes.SHA256(),
            16,
            salt=None,
            info=None,
            backend=backend
        )

        hkdf.verify(b"\x01" * 16, b"gJ\xfb{\xb1Oi\xc5sMC\xb7\xe4@\xf7u")

    def test_verify_invalid(self, backend):
        hkdf = HKDF(
            hashes.SHA256(),
            16,
            salt=None,
            info=None,
            backend=backend
        )

        with pytest.raises(InvalidKey):
            hkdf.verify(b"\x02" * 16, b"gJ\xfb{\xb1Oi\xc5sMC\xb7\xe4@\xf7u")

    def test_unicode_typeerror(self, backend):
        with pytest.raises(TypeError):
            HKDF(
                hashes.SHA256(),
                16,
                salt=six.u("foo"),
                info=None,
                backend=backend
            )

        with pytest.raises(TypeError):
            HKDF(
                hashes.SHA256(),
                16,
                salt=None,
                info=six.u("foo"),
                backend=backend
            )

        with pytest.raises(TypeError):
            hkdf = HKDF(
                hashes.SHA256(),
                16,
                salt=None,
                info=None,
                backend=backend
            )

            hkdf.derive(six.u("foo"))

        with pytest.raises(TypeError):
            hkdf = HKDF(
                hashes.SHA256(),
                16,
                salt=None,
                info=None,
                backend=backend
            )

            hkdf.verify(six.u("foo"), b"bar")

        with pytest.raises(TypeError):
            hkdf = HKDF(
                hashes.SHA256(),
                16,
                salt=None,
                info=None,
                backend=backend
            )

            hkdf.verify(b"foo", six.u("bar"))