Files
harbour-core/contrib/hbct/ctcrypt.c
2013-10-09 20:08:24 +02:00

129 lines
4.5 KiB
C

/*
* Harbour Project source code:
* Crypt() CA-T*ols compatible function
*
* Copyright 1999-2001 Viktor Szakats (vszakats.net/harbour)
* www - http://harbour-project.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this software; see the file COPYING.txt. If not, write to
* the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307 USA (or visit the web site http://www.gnu.org/).
*
* As a special exception, the Harbour Project gives permission for
* additional uses of the text contained in its release of Harbour.
*
* The exception is that, if you link the Harbour libraries with other
* files to produce an executable, this does not by itself cause the
* resulting executable to be covered by the GNU General Public License.
* Your use of that executable is in no way restricted on account of
* linking the Harbour library code into it.
*
* This exception does not however invalidate any other reasons why
* the executable file might be covered by the GNU General Public License.
*
* This exception applies only to the code released by the Harbour
* Project under the name Harbour. If you copy code from other
* Harbour Project or Free Software Foundation releases into a copy of
* Harbour, as the General Public License permits, the exception does
* not apply to the code that you add in this way. To avoid misleading
* anyone as to the status of such modified files, you must delete
* this exception notice from them.
*
* If you write modifications of your own for Harbour, it is your choice
* whether to permit this exception to apply to your modifications.
* If you do not wish that, delete this exception notice.
*
*/
#include "hbapi.h"
HB_FUNC( CRYPT )
{
HB_SIZE nCryptLen = hb_parclen( 2 );
if( nCryptLen >= 2 )
{
const HB_BYTE * pbyCrypt = ( const HB_BYTE * ) hb_parc( 2 );
HB_SIZE nCryptPos = 0;
const HB_BYTE * pbyString = ( const HB_BYTE * ) hb_parc( 1 );
HB_SIZE nStringLen = hb_parclen( 1 );
HB_SIZE nStringPos;
HB_BYTE * pbyResult = ( HB_BYTE * ) hb_xgrab( nStringLen + 1 );
HB_USHORT uiCount2 =
( ( ( HB_USHORT ) ( pbyCrypt[ nCryptPos ] + ( HB_USHORT ) ( pbyCrypt[ nCryptPos + 1 ] * 256 ) ) ) &
0xFFFF ) ^ ( ( HB_USHORT ) nCryptLen & 0xFFFF );
HB_USHORT uiCount1 = 0xAAAA;
for( nStringPos = 0; nStringPos < nStringLen; )
{
HB_USHORT uiTmpCount1 = uiCount1;
HB_USHORT uiTmpCount2 = uiCount2;
HB_BYTE byte = pbyString[ nStringPos ] ^ pbyCrypt[ nCryptPos++ ];
HB_USHORT tmp;
uiTmpCount2 =
HB_MKUSHORT( ( HB_LOBYTE( uiTmpCount2 ) ^ HB_HIBYTE( uiTmpCount2 ) ),
HB_HIBYTE( uiTmpCount2 ) );
for( tmp = HB_LOBYTE( uiTmpCount2 ); tmp; tmp-- )
uiTmpCount2 = ( uiTmpCount2 >> 1 ) | ( ( uiTmpCount2 & 1 ) << 15 );
uiTmpCount2 ^= uiTmpCount1;
uiTmpCount2 += 16;
uiCount2 = uiTmpCount2;
uiTmpCount2 &= 0x1E;
uiTmpCount2 += 2;
do
{
HB_BYTE byTmp;
uiTmpCount2--;
for( tmp = HB_LOBYTE( uiTmpCount2 ); tmp; tmp-- )
uiTmpCount1 = ( uiTmpCount1 >> 1 ) | ( ( uiTmpCount1 & 1 ) << 15 );
uiTmpCount1 = HB_MKUSHORT( HB_HIBYTE( uiTmpCount1 ), HB_LOBYTE( uiTmpCount1 ) );
uiTmpCount1 =
HB_MKUSHORT( ( HB_LOBYTE( uiTmpCount1 ) ^ 0xFF ), HB_HIBYTE( uiTmpCount1 ) );
uiTmpCount1 = ( uiTmpCount1 << 1 ) | ( ( uiTmpCount1 & 0x8000 ) >> 15 );
uiTmpCount1 ^= 0xAAAA;
byTmp = HB_LOBYTE( uiTmpCount1 );
byTmp = ( byTmp << 1 ) | ( ( byTmp & 0x80 ) >> 7 );
uiTmpCount1 = HB_MKUSHORT( byTmp, HB_HIBYTE( uiTmpCount1 ) );
}
while( --uiTmpCount2 );
uiCount1 = uiTmpCount1;
pbyResult[ nStringPos++ ] = byte ^ HB_LOBYTE( uiTmpCount1 );
if( nCryptPos == nCryptLen )
nCryptPos = 0;
}
hb_retclen_buffer( ( char * ) pbyResult, nStringLen );
}
else
hb_retc_null();
}