Digest.cpp

/*
 *  PKCS#11 library for .Net smart cards
 *  Copyright (C) 2007-2009 Gemalto <support@gemalto.com>
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#include <cstdlib>
#include <cstring>
#include "cryptoki.h"
#include "digest.h"
#include <memory>

CDigest::CDigest(){
    _counter       = 0;
    _workingOffset = 0;
    _workingLength = 0;
}

CDigest::~CDigest(){
    free(_hashValue);
    free(_workingBuffer);
}

void CDigest::hashCore( CK_BYTE_PTR data, const CK_LONG& a_ulOffset, const CK_LONG& a_ulCount )
{
	CK_LONG count = a_ulCount;
	CK_LONG offset = a_ulOffset;

    while (count > 0)
    {
        // prepare working buffer.
        if ((_workingOffset + count) >= _blockLength){
            _workingLength = _blockLength - _workingOffset;
        }
        else{
            _workingLength = count;
        }

        memcpy(&_workingBuffer[_workingOffset],&data[offset],_workingLength);

        _workingOffset += _workingLength;
        count -= _workingLength;
        offset += _workingLength;

        if ((_workingOffset == _blockLength) && (count > 0)){

            TransformBlock(_workingBuffer,_counter,_hashValue);

            _counter += _blockLength;
            _workingOffset = 0;
        }
    }
}

void CDigest::hashFinal(CK_BYTE_PTR hash)
{
    TransformFinalBlock(_workingBuffer,_workingOffset,_counter,_hashValue);
    memcpy(hash,_hashValue,_hashLength);
}