/****************************************************************************
**
** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
** Copyright (C) 2013 Richard J. Moore <rich@kde.org>.
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****************************************************************************/

#include <qcryptographichash.h>
#include <qiodevice.h>

#include "../../3rdparty/sha1/sha1.cpp"

#if defined(QT_BOOTSTRAPPED) && !defined(QT_CRYPTOGRAPHICHASH_ONLY_SHA1)
#  error "Are you sure you need the other hashing algorithms besides SHA-1?"
#endif

#ifndef QT_CRYPTOGRAPHICHASH_ONLY_SHA1
// qdoc and qmake only need SHA-1
#include "../../3rdparty/md5/md5.h"
#include "../../3rdparty/md5/md5.cpp"
#include "../../3rdparty/md4/md4.h"
#include "../../3rdparty/md4/md4.cpp"

typedef unsigned char BitSequence;
typedef unsigned long long DataLength;
typedef enum { SUCCESS = 0, FAIL = 1, BAD_HASHLEN = 2 } HashReturn;

#include "../../3rdparty/sha3/KeccakSponge.c"
typedef spongeState hashState;

#include "../../3rdparty/sha3/KeccakNISTInterface.c"

/*
  This lets us choose between SHA3 implementations at build time.
 */
typedef spongeState SHA3Context;
typedef HashReturn (SHA3Init)(hashState *state, int hashbitlen);
typedef HashReturn (SHA3Update)(hashState *state, const BitSequence *data, DataLength databitlen);
typedef HashReturn (SHA3Final)(hashState *state, BitSequence *hashval);

#if QT_POINTER_SIZE == 8 // 64 bit version

#include "../../3rdparty/sha3/KeccakF-1600-opt64.c"

static SHA3Init * const sha3Init = Init;
static SHA3Update * const sha3Update = Update;
static SHA3Final * const sha3Final = Final;

#else // 32 bit optimised fallback

#include "../../3rdparty/sha3/KeccakF-1600-opt32.c"

static SHA3Init * const sha3Init = Init;
static SHA3Update * const sha3Update = Update;
static SHA3Final * const sha3Final = Final;

#endif

/*
    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"

/*
    These 2 functions replace macros of the same name in sha224-256.c and
    sha384-512.c. Originally, these macros relied on a global static 'addTemp'
    variable. We do not want this for 2 reasons:

    1. since we are including the sources directly, the declaration of the 2 conflict

    2. static variables are not thread-safe, we do not want multiple threads
    computing a hash to corrupt one another
*/
static int SHA224_256AddLength(SHA256Context *context, unsigned int length);
static int SHA384_512AddLength(SHA512Context *context, unsigned int length);

// Sources from rfc6234, with 4 modifications:
// sha224-256.c - commented out 'static uint32_t addTemp;' on line 68
// sha224-256.c - appended 'M' to the SHA224_256AddLength macro on line 70
#include "../../3rdparty/rfc6234/sha224-256.c"
// sha384-512.c - commented out 'static uint64_t addTemp;' on line 302
// sha384-512.c - appended 'M' to the SHA224_256AddLength macro on line 304
#include "../../3rdparty/rfc6234/sha384-512.c"

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

static inline int SHA224_256AddLength(SHA256Context *context, unsigned int length)
{
  QT_PREPEND_NAMESPACE(quint32) addTemp;
  return SHA224_256AddLengthM(context, length);
}
static inline int SHA384_512AddLength(SHA512Context *context, unsigned int length)
{
  QT_PREPEND_NAMESPACE(quint64) addTemp;
  return SHA384_512AddLengthM(context, length);
}
#endif // QT_CRYPTOGRAPHICHASH_ONLY_SHA1

QT_BEGIN_NAMESPACE

class QCryptographicHashPrivate
{
public:
    QCryptographicHash::Algorithm method;
    union {
        Sha1State sha1Context;
#ifndef QT_CRYPTOGRAPHICHASH_ONLY_SHA1
        MD5Context md5Context;
        md4_context md4Context;
        SHA224Context sha224Context;
        SHA256Context sha256Context;
        SHA384Context sha384Context;
        SHA512Context sha512Context;
        SHA3Context sha3Context;
#endif
    };
    QByteArray result;
};

/*!
  \class QCryptographicHash
  \inmodule QtCore

  \brief The QCryptographicHash class provides a way to generate cryptographic hashes.

  \since 4.3

  \ingroup tools
  \reentrant

  QCryptographicHash can be used to generate cryptographic hashes of binary or text data.

  Currently MD4, MD5, SHA-1, SHA-224, SHA-256, SHA-384, and SHA-512 are supported.
*/

/*!
  \enum QCryptographicHash::Algorithm

  \value Md4 Generate an MD4 hash sum
  \value Md5 Generate an MD5 hash sum
  \value Sha1 Generate an SHA-1 hash sum
  \value Sha224 Generate an SHA-224 hash sum (SHA-2). Introduced in Qt 5.0
  \value Sha256 Generate an SHA-256 hash sum (SHA-2). Introduced in Qt 5.0
  \value Sha384 Generate an SHA-384 hash sum (SHA-2). Introduced in Qt 5.0
  \value Sha512 Generate an SHA-512 hash sum (SHA-2). Introduced in Qt 5.0
  \value Sha3_224 Generate an SHA3-224 hash sum. Introduced in Qt 5.1
  \value Sha3_256 Generate an SHA3-256 hash sum. Introduced in Qt 5.1
  \value Sha3_384 Generate an SHA3-384 hash sum. Introduced in Qt 5.1
  \value Sha3_512 Generate an SHA3-512 hash sum. Introduced in Qt 5.1
*/

/*!
  Constructs an object that can be used to create a cryptographic hash from data using \a method.
*/
QCryptographicHash::QCryptographicHash(Algorithm method)
    : d(new QCryptographicHashPrivate)
{
    d->method = method;
    reset();
}

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

/*!
  Resets the object.
*/
void QCryptographicHash::reset()
{
    switch (d->method) {
    case Sha1:
        sha1InitState(&d->sha1Context);
        break;
#ifdef QT_CRYPTOGRAPHICHASH_ONLY_SHA1
    default:
        Q_ASSERT_X(false, "QCryptographicHash", "Method not compiled in");
        Q_UNREACHABLE();
        break;
#else
    case Md4:
        md4_init(&d->md4Context);
        break;
    case Md5:
        MD5Init(&d->md5Context);
        break;
    case Sha224:
        SHA224Reset(&d->sha224Context);
        break;
    case Sha256:
        SHA256Reset(&d->sha256Context);
        break;
    case Sha384:
        SHA384Reset(&d->sha384Context);
        break;
    case Sha512:
        SHA512Reset(&d->sha512Context);
        break;
    case Sha3_224:
        sha3Init(&d->sha3Context, 224);
        break;
    case Sha3_256:
        sha3Init(&d->sha3Context, 256);
        break;
    case Sha3_384:
        sha3Init(&d->sha3Context, 384);
        break;
    case Sha3_512:
        sha3Init(&d->sha3Context, 512);
        break;
#endif
    }
    d->result.clear();
}

/*!
    Adds the first \a length chars of \a data to the cryptographic
    hash.
*/
void QCryptographicHash::addData(const char *data, int length)
{
    switch (d->method) {
    case Sha1:
        sha1Update(&d->sha1Context, (const unsigned char *)data, length);
        break;
#ifdef QT_CRYPTOGRAPHICHASH_ONLY_SHA1
    default:
        Q_ASSERT_X(false, "QCryptographicHash", "Method not compiled in");
        Q_UNREACHABLE();
        break;
#else
    case Md4:
        md4_update(&d->md4Context, (const unsigned char *)data, length);
        break;
    case Md5:
        MD5Update(&d->md5Context, (const unsigned char *)data, length);
        break;
    case Sha224:
        SHA224Input(&d->sha224Context, reinterpret_cast<const unsigned char *>(data), length);
        break;
    case Sha256:
        SHA256Input(&d->sha256Context, reinterpret_cast<const unsigned char *>(data), length);
        break;
    case Sha384:
        SHA384Input(&d->sha384Context, reinterpret_cast<const unsigned char *>(data), length);
        break;
    case Sha512:
        SHA512Input(&d->sha512Context, reinterpret_cast<const unsigned char *>(data), length);
        break;
    case Sha3_224:
        sha3Update(&d->sha3Context, reinterpret_cast<const BitSequence *>(data), length*8);
        break;
    case Sha3_256:
        sha3Update(&d->sha3Context, reinterpret_cast<const BitSequence *>(data), length*8);
        break;
    case Sha3_384:
        sha3Update(&d->sha3Context, reinterpret_cast<const BitSequence *>(data), length*8);
        break;
    case Sha3_512:
        sha3Update(&d->sha3Context, reinterpret_cast<const BitSequence *>(data), length*8);
        break;
#endif
    }
    d->result.clear();
}

/*!
  \overload addData()
*/
void QCryptographicHash::addData(const QByteArray &data)
{
    addData(data.constData(), data.length());
}

/*!
  Reads the data from the open QIODevice \a device until it ends
  and hashes it. Returns \c true if reading was successful.
  \since 5.0
 */
bool QCryptographicHash::addData(QIODevice* device)
{
    if (!device->isReadable())
        return false;

    if (!device->isOpen())
        return false;

    char buffer[1024];
    int length;

    while ((length = device->read(buffer,sizeof(buffer))) > 0)
        addData(buffer,length);

    return device->atEnd();
}


/*!
  Returns the final hash value.

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

    switch (d->method) {
    case Sha1: {
        Sha1State copy = d->sha1Context;
        d->result.resize(20);
        sha1FinalizeState(&copy);
        sha1ToHash(&copy, (unsigned char *)d->result.data());
        break;
    }
#ifdef QT_CRYPTOGRAPHICHASH_ONLY_SHA1
    default:
        Q_ASSERT_X(false, "QCryptographicHash", "Method not compiled in");
        Q_UNREACHABLE();
        break;
#else
    case Md4: {
        md4_context copy = d->md4Context;
        d->result.resize(MD4_RESULTLEN);
        md4_final(&copy, (unsigned char *)d->result.data());
        break;
    }
    case Md5: {
        MD5Context copy = d->md5Context;
        d->result.resize(16);
        MD5Final(&copy, (unsigned char *)d->result.data());
        break;
    }
    case Sha224: {
        SHA224Context copy = d->sha224Context;
        d->result.resize(SHA224HashSize);
        SHA224Result(&copy, reinterpret_cast<unsigned char *>(d->result.data()));
        break;
    }
    case Sha256:{
        SHA256Context copy = d->sha256Context;
        d->result.resize(SHA256HashSize);
        SHA256Result(&copy, reinterpret_cast<unsigned char *>(d->result.data()));
        break;
    }
    case Sha384:{
        SHA384Context copy = d->sha384Context;
        d->result.resize(SHA384HashSize);
        SHA384Result(&copy, reinterpret_cast<unsigned char *>(d->result.data()));
        break;
    }
    case Sha512:{
        SHA512Context copy = d->sha512Context;
        d->result.resize(SHA512HashSize);
        SHA512Result(&copy, reinterpret_cast<unsigned char *>(d->result.data()));
        break;
    }
    case Sha3_224: {
        SHA3Context copy = d->sha3Context;
        d->result.resize(224/8);
        sha3Final(&copy, reinterpret_cast<BitSequence *>(d->result.data()));
        break;
    }
    case Sha3_256: {
        SHA3Context copy = d->sha3Context;
        d->result.resize(256/8);
        sha3Final(&copy, reinterpret_cast<BitSequence *>(d->result.data()));
        break;
    }
    case Sha3_384: {
        SHA3Context copy = d->sha3Context;
        d->result.resize(384/8);
        sha3Final(&copy, reinterpret_cast<BitSequence *>(d->result.data()));
        break;
    }
    case Sha3_512: {
        SHA3Context copy = d->sha3Context;
        d->result.resize(512/8);
        sha3Final(&copy, reinterpret_cast<BitSequence *>(d->result.data()));
        break;
    }
#endif
    }
    return d->result;
}

/*!
  Returns the hash of \a data using \a method.
*/
QByteArray QCryptographicHash::hash(const QByteArray &data, Algorithm method)
{
    QCryptographicHash hash(method);
    hash.addData(data);
    return hash.result();
}

QT_END_NAMESPACE
