summaryrefslogtreecommitdiff
path: root/src/corelib/tools/qmessageauthenticationcode.cpp
blob: 5e7f1fc4313488617f8883dbd2d3b177bb36b696 (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
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
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
/****************************************************************************
**
** Copyright (C) 2013 Ruslan Nigmatullin <euroelessar@yandex.ru>
** Contact: http://www.qt.io/licensing/
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL21$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see http://www.qt.io/terms-conditions. For further
** information use the contact form at http://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 or version 3 as published by the Free
** Software Foundation and appearing in the file LICENSE.LGPLv21 and
** LICENSE.LGPLv3 included in the packaging of this file. Please review the
** following information to ensure the GNU Lesser General Public License
** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** As a special exception, The Qt Company gives you certain additional
** rights. These rights are described in The Qt Company LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qmessageauthenticationcode.h"
#include "qvarlengtharray.h"

/*
    These #defines replace the typedefs needed by the RFC6234 code. Normally
    the typedefs would come from from stdint.h, but since this header is not
    available on all platforms (MSVC 2008, for example), we #define them to the
    Qt equivalents.
*/
#define uint64_t QT_PREPEND_NAMESPACE(quint64)
#define uint32_t QT_PREPEND_NAMESPACE(quint32)
#define uint8_t QT_PREPEND_NAMESPACE(quint8)
#define int_least16_t QT_PREPEND_NAMESPACE(qint16)

// Header from rfc6234 with 1 modification:
// sha1.h - commented out '#include <stdint.h>' on line 74
#include "../../3rdparty/rfc6234/sha.h"

#undef uint64_t
#undef uint32_t
#undef uint68_t
#undef int_least16_t

QT_BEGIN_NAMESPACE

static int qt_hash_block_size(QCryptographicHash::Algorithm method)
{
    switch (method) {
    case QCryptographicHash::Md4:
        return 64;
    case QCryptographicHash::Md5:
        return 64;
    case QCryptographicHash::Sha1:
        return SHA1_Message_Block_Size;
    case QCryptographicHash::Sha224:
        return SHA224_Message_Block_Size;
    case QCryptographicHash::Sha256:
        return SHA256_Message_Block_Size;
    case QCryptographicHash::Sha384:
        return SHA384_Message_Block_Size;
    case QCryptographicHash::Sha512:
        return SHA512_Message_Block_Size;
    case QCryptographicHash::Sha3_224:
        return 144;
    case QCryptographicHash::Sha3_256:
        return 136;
    case QCryptographicHash::Sha3_384:
        return 104;
    case QCryptographicHash::Sha3_512:
        return 72;
    }
    return 0;
}

class QMessageAuthenticationCodePrivate
{
public:
    QMessageAuthenticationCodePrivate(QCryptographicHash::Algorithm m)
        : messageHash(m), method(m), messageHashInited(false)
    {
    }

    QByteArray key;
    QByteArray result;
    QCryptographicHash messageHash;
    QCryptographicHash::Algorithm method;
    bool messageHashInited;

    void initMessageHash();
};

void QMessageAuthenticationCodePrivate::initMessageHash()
{
    if (messageHashInited)
        return;
    messageHashInited = true;

    const int blockSize = qt_hash_block_size(method);

    if (key.size() > blockSize) {
        QCryptographicHash hash(method);
        hash.addData(key);
        key = hash.result();
        hash.reset();
    }

    if (key.size() < blockSize) {
        const int size = key.size();
        key.resize(blockSize);
        memset(key.data() + size, 0, blockSize - size);
    }

    QVarLengthArray<char> iKeyPad(blockSize);
    const char * const keyData = key.constData();

    for (int i = 0; i < blockSize; ++i)
        iKeyPad[i] = keyData[i] ^ 0x36;

    messageHash.addData(iKeyPad.data(), iKeyPad.size());
}

/*!
    \class QMessageAuthenticationCode
    \inmodule QtCore

    \brief The QMessageAuthenticationCode class provides a way to generate
    hash-based message authentication codes.

    \since 5.1

    \ingroup tools
    \reentrant

    QMessageAuthenticationCode supports all cryptographic hashes which are supported by
    QCryptographicHash.

    To generate message authentication code, pass hash algorithm QCryptographicHash::Algorithm
    to constructor, then set key and message by setKey() and addData() functions. Result
    can be acquired by result() function.
    \snippet qmessageauthenticationcode/main.cpp 0
    \dots
    \snippet qmessageauthenticationcode/main.cpp 1

    Alternatively, this effect can be achieved by providing message,
    key and method to hash() method.
    \snippet qmessageauthenticationcode/main.cpp 2

    \sa QCryptographicHash
*/

/*!
    Constructs an object that can be used to create a cryptographic hash from data
    using method \a method and key \a key.
*/
QMessageAuthenticationCode::QMessageAuthenticationCode(QCryptographicHash::Algorithm method,
                                                       const QByteArray &key)
    : d(new QMessageAuthenticationCodePrivate(method))
{
    d->key = key;
}

/*!
    Destroys the object.
*/
QMessageAuthenticationCode::~QMessageAuthenticationCode()
{
    delete d;
}

/*!
    Resets message data. Calling this method doesn't affect the key.
*/
void QMessageAuthenticationCode::reset()
{
    d->result.clear();
    d->messageHash.reset();
    d->messageHashInited = false;
}

/*!
    Sets secret \a key. Calling this method automatically resets the object state.
*/
void QMessageAuthenticationCode::setKey(const QByteArray &key)
{
    reset();
    d->key = key;
}

/*!
    Adds the first \a length chars of \a data to the message.
*/
void QMessageAuthenticationCode::addData(const char *data, int length)
{
    d->initMessageHash();
    d->messageHash.addData(data, length);
}

/*!
    \overload addData()
*/
void QMessageAuthenticationCode::addData(const QByteArray &data)
{
    d->initMessageHash();
    d->messageHash.addData(data);
}

/*!
    Reads the data from the open QIODevice \a device until it ends
    and adds it to message. Returns \c true if reading was successful.

    \note \a device must be already opened.
 */
bool QMessageAuthenticationCode::addData(QIODevice *device)
{
    d->initMessageHash();
    return d->messageHash.addData(device);
}

/*!
    Returns the final authentication code.

    \sa QByteArray::toHex()
*/
QByteArray QMessageAuthenticationCode::result() const
{
    if (!d->result.isEmpty())
        return d->result;

    d->initMessageHash();

    const int blockSize = qt_hash_block_size(d->method);

    QByteArray hashedMessage = d->messageHash.result();

    QVarLengthArray<char> oKeyPad(blockSize);
    const char * const keyData = d->key.constData();

    for (int i = 0; i < blockSize; ++i)
        oKeyPad[i] = keyData[i] ^ 0x5c;

    QCryptographicHash hash(d->method);
    hash.addData(oKeyPad.data(), oKeyPad.size());
    hash.addData(hashedMessage);

    d->result = hash.result();
    return d->result;
}

/*!
    Returns the authentication code for the message \a message using
    the key \a key and the method \a method.
*/
QByteArray QMessageAuthenticationCode::hash(const QByteArray &message, const QByteArray &key,
                                            QCryptographicHash::Algorithm method)
{
    QMessageAuthenticationCode mac(method);
    mac.setKey(key);
    mac.addData(message);
    return mac.result();
}

QT_END_NAMESPACE