Introduce QPasswordDigestor functions
Added a few functions to derive keys from passwords. Currently it supports PBKDF1 and PBKDF2 as defined in RFC 8018 ( https://tools.ietf.org/html/rfc8018 ). [ChangeLog][QtNetwork][QPasswordDigestor] Added QPasswordDigestor Task-number: QTBUG-30550 Change-Id: I2166b518bd8b54e3486514166e76fd9ba2f219c8 Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io> Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
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src/network/ssl/qpassworddigestor.cpp
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187
src/network/ssl/qpassworddigestor.cpp
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/****************************************************************************
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**
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** Copyright (C) 2018 The Qt Company Ltd.
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** Contact: https://www.qt.io/licensing/
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**
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** This file is part of the QtCore module of the Qt Toolkit.
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**
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** $QT_BEGIN_LICENSE:LGPL$
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** Commercial License Usage
|
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** 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 https://www.qt.io/terms-conditions. For further
|
||||
** information use the contact form at https://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 3 as published by the Free Software
|
||||
** Foundation and appearing in the file LICENSE.LGPL3 included in the
|
||||
** packaging of this file. Please review the following information to
|
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** ensure the GNU Lesser General Public License version 3 requirements
|
||||
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
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||||
**
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||||
** GNU General Public License Usage
|
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** Alternatively, this file may be used under the terms of the GNU
|
||||
** General Public License version 2.0 or (at your option) the GNU General
|
||||
** Public license version 3 or any later version approved by the KDE Free
|
||||
** Qt Foundation. The licenses are as published by the Free Software
|
||||
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
|
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** included in the packaging of this file. Please review the following
|
||||
** information to ensure the GNU General Public License requirements will
|
||||
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
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** https://www.gnu.org/licenses/gpl-3.0.html.
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**
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** $QT_END_LICENSE$
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**
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****************************************************************************/
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#include "qpassworddigestor.h"
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#include <QtCore/QDebug>
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#include <QtCore/QMessageAuthenticationCode>
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#include <QtCore/QtEndian>
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#include <limits>
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QT_BEGIN_NAMESPACE
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namespace QPasswordDigestor {
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/*!
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\namespace QPasswordDigestor
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\inmodule QtNetwork
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\brief The QPasswordDigestor namespace contains functions which you can use
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to generate hashes or keys.
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*/
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/*!
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\since 5.12
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Returns a hash computed using the PBKDF1-algorithm as defined in
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\l {https://tools.ietf.org/html/rfc8018#section-5.1} {RFC 8018}.
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The function takes the \a data and \a salt, and then hashes it repeatedly
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for \a iterations iterations using the specified hash \a algorithm. If the
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resulting hash is longer than \a dkLen then it is truncated before it is
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returned.
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This function only supports SHA-1 and MD5! The max output size is 160 bits
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(20 bytes) when using SHA-1, or 128 bits (16 bytes) when using MD5.
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Specifying a value for \a dkLen which is greater than this results in a
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warning and an empty QByteArray is returned. To programmatically check this
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limit you can use \l {QCryptographicHash::hashLength}. Furthermore: the
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\a salt must always be 8 bytes long!
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\note This function is provided for use with legacy applications and all
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new applications are recommended to use \l {pbkdf2} {PBKDF2}.
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\sa deriveKeyPbkdf2, QCryptographicHash, QCryptographicHash::hashLength
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*/
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Q_NETWORK_EXPORT QByteArray deriveKeyPbkdf1(QCryptographicHash::Algorithm algorithm,
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const QByteArray &data, const QByteArray &salt,
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int iterations, quint64 dkLen)
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{
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// https://tools.ietf.org/html/rfc8018#section-5.1
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if (algorithm != QCryptographicHash::Sha1
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#ifndef QT_CRYPTOGRAPHICHASH_ONLY_SHA1
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&& algorithm != QCryptographicHash::Md5
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#endif
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) {
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qWarning("The only supported algorithms for pbkdf1 are SHA-1 and MD5!");
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return QByteArray();
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}
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if (salt.size() != 8) {
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qWarning("The salt must be 8 bytes long!");
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return QByteArray();
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}
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if (iterations < 1 || dkLen < 1)
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return QByteArray();
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if (dkLen > quint64(QCryptographicHash::hashLength(algorithm))) {
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qWarning() << "Derived key too long:\n"
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<< algorithm << "was chosen which produces output of length"
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<< QCryptographicHash::hashLength(algorithm) << "but" << dkLen
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<< "was requested.";
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return QByteArray();
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}
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QCryptographicHash hash(algorithm);
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hash.addData(data);
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hash.addData(salt);
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QByteArray key = hash.result();
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for (int i = 1; i < iterations; i++) {
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hash.reset();
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hash.addData(key);
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key = hash.result();
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}
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return key.left(dkLen);
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}
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/*!
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\since 5.12
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Derive a key using the PBKDF2-algorithm as defined in
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\l {https://tools.ietf.org/html/rfc8018#section-5.2} {RFC 8018}.
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This function takes the \a data and \a salt, and then applies HMAC-X, where
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the X is \a algorithm, repeatedly. It internally concatenates intermediate
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results to the final output until at least \a dkLen amount of bytes have
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been computed and it will execute HMAC-X \a iterations times each time a
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concatenation is required. The total number of times it will execute HMAC-X
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depends on \a iterations, \a dkLen and \a algorithm and can be calculated
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as
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\c{iterations * ceil(dkLen / QCryptographicHash::hashLength(algorithm))}.
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\sa deriveKeyPbkdf1, QMessageAuthenticationCode, QCryptographicHash
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*/
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Q_NETWORK_EXPORT QByteArray deriveKeyPbkdf2(QCryptographicHash::Algorithm algorithm,
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const QByteArray &data, const QByteArray &salt,
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int iterations, quint64 dkLen)
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{
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// https://tools.ietf.org/html/rfc8018#section-5.2
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// The RFC recommends checking that 'dkLen' is not greater than '(2^32 - 1) * hLen'
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int hashLen = QCryptographicHash::hashLength(algorithm);
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const quint64 maxLen = quint64(std::numeric_limits<quint32>::max() - 1) * hashLen;
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if (dkLen > maxLen) {
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qWarning().nospace() << "Derived key too long:\n"
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<< algorithm << " was chosen which produces output of length "
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<< maxLen << " but " << dkLen << " was requested.";
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return QByteArray();
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}
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if (iterations < 1 || dkLen < 1)
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return QByteArray();
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QByteArray key;
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quint32 currentIteration = 1;
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QMessageAuthenticationCode hmac(algorithm, data);
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QByteArray index(4, Qt::Uninitialized);
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while (quint64(key.length()) < dkLen) {
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hmac.addData(salt);
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qToBigEndian(currentIteration, index.data());
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hmac.addData(index);
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QByteArray u = hmac.result();
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hmac.reset();
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QByteArray tkey = u;
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for (int iter = 1; iter < iterations; iter++) {
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hmac.addData(u);
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u = hmac.result();
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hmac.reset();
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std::transform(tkey.cbegin(), tkey.cend(), u.cbegin(), tkey.begin(),
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std::bit_xor<char>());
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}
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key += tkey;
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currentIteration++;
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}
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return key.left(dkLen);
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}
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} // namespace QPasswordDigestor
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QT_END_NAMESPACE
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60
src/network/ssl/qpassworddigestor.h
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60
src/network/ssl/qpassworddigestor.h
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@ -0,0 +1,60 @@
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/****************************************************************************
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**
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** Copyright (C) 2018 The Qt Company Ltd.
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** Contact: https://www.qt.io/licensing/
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**
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** This file is part of the QtCore module of the Qt Toolkit.
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**
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** $QT_BEGIN_LICENSE:LGPL$
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** Commercial License Usage
|
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** 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 https://www.qt.io/terms-conditions. For further
|
||||
** information use the contact form at https://www.qt.io/contact-us.
|
||||
**
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||||
** GNU Lesser General Public License Usage
|
||||
** Alternatively, this file may be used under the terms of the GNU Lesser
|
||||
** General Public License version 3 as published by the Free Software
|
||||
** Foundation and appearing in the file LICENSE.LGPL3 included in the
|
||||
** packaging of this file. Please review the following information to
|
||||
** ensure the GNU Lesser General Public License version 3 requirements
|
||||
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
|
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**
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** GNU General Public License Usage
|
||||
** Alternatively, this file may be used under the terms of the GNU
|
||||
** General Public License version 2.0 or (at your option) the GNU General
|
||||
** Public license version 3 or any later version approved by the KDE Free
|
||||
** Qt Foundation. The licenses are as published by the Free Software
|
||||
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
|
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** included in the packaging of this file. Please review the following
|
||||
** information to ensure the GNU General Public License requirements will
|
||||
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
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** https://www.gnu.org/licenses/gpl-3.0.html.
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**
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** $QT_END_LICENSE$
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**
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****************************************************************************/
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#ifndef QPASSWORDDIGESTOR_H
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#define QPASSWORDDIGESTOR_H
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#include <QtNetwork/qtnetworkglobal.h>
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#include <QtCore/QByteArray>
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#include <QtCore/QCryptographicHash>
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QT_BEGIN_NAMESPACE
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namespace QPasswordDigestor {
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Q_NETWORK_EXPORT QByteArray deriveKeyPbkdf1(QCryptographicHash::Algorithm algorithm,
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const QByteArray &password, const QByteArray &salt,
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int iterations, quint64 dkLen);
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Q_NETWORK_EXPORT QByteArray deriveKeyPbkdf2(QCryptographicHash::Algorithm algorithm,
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const QByteArray &password, const QByteArray &salt,
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int iterations, quint64 dkLen);
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} // namespace QPasswordDigestor
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QT_END_NAMESPACE
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#endif // QPASSWORDDIGESTOR_H
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}
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}
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}
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HEADERS += ssl/qpassworddigestor.h
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SOURCES += ssl/qpassworddigestor.cpp
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CONFIG += testcase
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TARGET = tst_qpassworddigestor
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QT = core network testlib
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SOURCES = tst_qpassworddigestor.cpp
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/****************************************************************************
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**
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** Copyright (C) 2018 The Qt Company Ltd.
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** Contact: https://www.qt.io/licensing/
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**
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** This file is part of the test suite of the Qt Toolkit.
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**
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** $QT_BEGIN_LICENSE:GPL-EXCEPT$
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** Commercial License Usage
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** Licensees holding valid commercial Qt licenses may use this file in
|
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** 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
|
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** and conditions see https://www.qt.io/terms-conditions. For further
|
||||
** information use the contact form at https://www.qt.io/contact-us.
|
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**
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** GNU General Public License Usage
|
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** Alternatively, this file may be used under the terms of the GNU
|
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** General Public License version 3 as published by the Free Software
|
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** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
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** included in the packaging of this file. Please review the following
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** information to ensure the GNU General Public License requirements will
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** be met: https://www.gnu.org/licenses/gpl-3.0.html.
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**
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** $QT_END_LICENSE$
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**
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****************************************************************************/
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#include <QtTest/QtTest>
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#include <QtNetwork/qpassworddigestor.h>
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#include <QtCore/QByteArray>
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class tst_QPasswordDigestor : public QObject
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{
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Q_OBJECT
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private Q_SLOTS:
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void pbkdf1Vectors_data();
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void pbkdf1Vectors();
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void pbkdf2Vectors_data();
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void pbkdf2Vectors();
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};
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void tst_QPasswordDigestor::pbkdf1Vectors_data()
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{
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QTest::addColumn<QCryptographicHash::Algorithm>("algorithm");
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QTest::addColumn<QByteArray>("password");
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QTest::addColumn<QByteArray>("salt");
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QTest::addColumn<int>("iterations");
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QTest::addColumn<int>("dkLen");
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QTest::addColumn<QByteArray>("result");
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// data from
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// https://web.archive.org/web/20160912052752/https://www.di-mgt.com.au/cryptoKDFs.html#examplespbkdf
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// (Note: this is not official, but at least it's something to compare with.)
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QTest::newRow("di-mgt") << QCryptographicHash::Sha1 << QByteArray::fromHex("70617373776F7264")
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<< QByteArray::fromHex("78578E5A5D63CB06") << 1000 << 16
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<< QByteArray::fromHex("DC19847E05C64D2FAF10EBFB4A3D2A20");
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}
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void tst_QPasswordDigestor::pbkdf1Vectors()
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{
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QFETCH(QCryptographicHash::Algorithm, algorithm);
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QFETCH(QByteArray, password);
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QFETCH(QByteArray, salt);
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QFETCH(int, iterations);
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QFETCH(int, dkLen);
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QFETCH(QByteArray, result);
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QCOMPARE(QPasswordDigestor::deriveKeyPbkdf1(algorithm, password, salt, iterations, dkLen), result);
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}
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void tst_QPasswordDigestor::pbkdf2Vectors_data()
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{
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QTest::addColumn<QCryptographicHash::Algorithm>("algorithm");
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QTest::addColumn<QByteArray>("password");
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QTest::addColumn<QByteArray>("salt");
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QTest::addColumn<int>("iterations");
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QTest::addColumn<int>("dkLen");
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QTest::addColumn<QByteArray>("result");
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// data from https://tools.ietf.org/html/rfc6070
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auto hash = QCryptographicHash::Sha1;
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QTest::newRow("rfc6070-1") << hash << QByteArrayLiteral("password") << QByteArrayLiteral("salt")
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<< 1 << 20
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<< QByteArray::fromHex("0c60c80f961f0e71f3a9b524af6012062fe037a6");
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QTest::newRow("rfc6070-2") << hash << QByteArrayLiteral("password") << QByteArrayLiteral("salt")
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<< 2 << 20
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<< QByteArray::fromHex("ea6c014dc72d6f8ccd1ed92ace1d41f0d8de8957");
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QTest::newRow("rfc6070-3") << hash << QByteArrayLiteral("password") << QByteArrayLiteral("salt")
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<< 4096 << 20
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<< QByteArray::fromHex("4b007901b765489abead49d926f721d065a429c1");
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#if 0
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// Excluding: takes about 3 minutes to run
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QTest::newRow("rfc6070-4") << hash << QByteArrayLiteral("password") << QByteArrayLiteral("salt")
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<< 16777216 << 20
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<< QByteArray::fromHex("eefe3d61cd4da4e4e9945b3d6ba2158c2634e984");
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#endif
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QTest::newRow("rfc6070-5") << hash << QByteArrayLiteral("passwordPASSWORDpassword")
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<< QByteArrayLiteral("saltSALTsaltSALTsaltSALTsaltSALTsalt") << 4096
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<< 25
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<< QByteArray::fromHex(
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"3d2eec4fe41c849b80c8d83662c0e44a8b291a964cf2f07038");
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QTest::newRow("rfc6070-6") << hash << QByteArrayLiteral("pass\0word")
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<< QByteArrayLiteral("sa\0lt") << 4096 << 16
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<< QByteArray::fromHex("56fa6aa75548099dcc37d7f03425e0c3");
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// the next few bits of data are from https://tools.ietf.org/html/rfc3962#appendix-B
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QByteArray password = QByteArrayLiteral("password");
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QByteArray salt = QByteArrayLiteral("ATHENA.MIT.EDUraeburn");
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QTest::newRow("rfc3962-1") << hash << password << salt << 1 << 16
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<< QByteArray::fromHex("cdedb5281bb2f801565a1122b2563515");
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QTest::newRow("rfc3962-2")
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<< hash << password << salt << 1 << 32
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<< QByteArray::fromHex("cdedb5281bb2f801565a1122b25635150ad1f7a04bb9f3a333ecc0e2e1f70837");
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QTest::newRow("rfc3962-3") << hash << password << salt << 2 << 16
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<< QByteArray::fromHex("01dbee7f4a9e243e988b62c73cda935d");
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QTest::newRow("rfc3962-4")
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<< hash << QByteArrayLiteral("password") << salt << 2 << 32
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<< QByteArray::fromHex("01dbee7f4a9e243e988b62c73cda935da05378b93244ec8f48a99e61ad799d86");
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QTest::newRow("rfc3962-5") << hash << password << salt << 1200 << 16
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<< QByteArray::fromHex("5c08eb61fdf71e4e4ec3cf6ba1f5512b");
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QTest::newRow("rfc3962-6")
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<< hash << password << salt << 1200 << 32
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<< QByteArray::fromHex("5c08eb61fdf71e4e4ec3cf6ba1f5512ba7e52ddbc5e5142f708a31e2e62b1e13");
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salt = QByteArray::fromHex("1234567878563412"); // 0x1234567878563412
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QTest::newRow("rfc3962-7") << hash << password << salt << 5 << 16
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<< QByteArray::fromHex("d1daa78615f287e6a1c8b120d7062a49");
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QTest::newRow("rfc3962-8")
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<< hash << password << salt << 5 << 32
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<< QByteArray::fromHex("d1daa78615f287e6a1c8b120d7062a493f98d203e6be49a6adf4fa574b6e64ee");
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password = QByteArray(64, 'X');
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salt = "pass phrase equals block size";
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QTest::newRow("rfc3962-9") << hash << password << salt << 1200 << 16
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<< QByteArray::fromHex("139c30c0966bc32ba55fdbf212530ac9");
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QTest::newRow("rfc3962-10")
|
||||
<< hash << password << salt << 1200 << 32
|
||||
<< QByteArray::fromHex("139c30c0966bc32ba55fdbf212530ac9c5ec59f1a452f5cc9ad940fea0598ed1");
|
||||
|
||||
password.append('X');
|
||||
salt = "pass phrase exceeds block size";
|
||||
QTest::newRow("rfc3962-11") << hash << password << salt << 1200 << 16
|
||||
<< QByteArray::fromHex("9ccad6d468770cd51b10e6a68721be61");
|
||||
QTest::newRow("rfc3962-12")
|
||||
<< hash << password << salt << 1200 << 32
|
||||
<< QByteArray::fromHex("9ccad6d468770cd51b10e6a68721be611a8b4d282601db3b36be9246915ec82a");
|
||||
|
||||
password = QByteArray::fromHex("f09d849e"); // 0xf09d849e
|
||||
salt = "EXAMPLE.COMpianist";
|
||||
QTest::newRow("rfc3962-13") << hash << password << salt << 50 << 16
|
||||
<< QByteArray::fromHex("6b9cf26d45455a43a5b8bb276a403b39");
|
||||
QTest::newRow("rfc3962-14")
|
||||
<< hash << password << salt << 50 << 32
|
||||
<< QByteArray::fromHex("6b9cf26d45455a43a5b8bb276a403b39e7fe37a0c41e02c281ff3069e1e94f52");
|
||||
}
|
||||
|
||||
void tst_QPasswordDigestor::pbkdf2Vectors()
|
||||
{
|
||||
QFETCH(QCryptographicHash::Algorithm, algorithm);
|
||||
QFETCH(QByteArray, password);
|
||||
QFETCH(QByteArray, salt);
|
||||
QFETCH(int, iterations);
|
||||
QFETCH(int, dkLen);
|
||||
QFETCH(QByteArray, result);
|
||||
|
||||
QCOMPARE(QPasswordDigestor::deriveKeyPbkdf2(algorithm, password, salt, iterations, dkLen), result);
|
||||
}
|
||||
|
||||
QTEST_MAIN(tst_QPasswordDigestor)
|
||||
#include "tst_qpassworddigestor.moc"
|
@ -2,6 +2,7 @@ TEMPLATE=subdirs
|
||||
QT_FOR_CONFIG += network
|
||||
|
||||
SUBDIRS=\
|
||||
qpassworddigestor \
|
||||
qsslcertificate \
|
||||
qsslcipher \
|
||||
qsslellipticcurve \
|
||||
|
Loading…
Reference in New Issue
Block a user