drivers/staging/wlags49_h2/wl_enc.c

/*******************************************************************************
 * Agere Systems Inc.
 * Wireless device driver for Linux (wlags49).
 *
 * Copyright (c) 1998-2003 Agere Systems Inc.
 * All rights reserved.
 *   http://www.agere.com
 *
 * Initially developed by TriplePoint, Inc.
 *   http://www.triplepoint.com
 *
 *------------------------------------------------------------------------------
 *
 *   This file defines functions related to WEP key coding/decoding.
 *
 *------------------------------------------------------------------------------
 *
 * SOFTWARE LICENSE
 *
 * This software is provided subject to the following terms and conditions,
 * which you should read carefully before using the software.  Using this
 * software indicates your acceptance of these terms and conditions.  If you do
 * not agree with these terms and conditions, do not use the software.
 *
 * Copyright © 2003 Agere Systems Inc.
 * All rights reserved.
 *
 * Redistribution and use in source or binary forms, with or without
 * modifications, are permitted provided that the following conditions are met:
 *
 * . Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following Disclaimer as comments in the code as
 *    well as in the documentation and/or other materials provided with the
 *    distribution.
 *
 * . Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following Disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * . Neither the name of Agere Systems Inc. nor the names of the contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * Disclaimer
 *
 * THIS SOFTWARE IS PROVIDED “AS IS” AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, INFRINGEMENT AND THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  ANY
 * USE, MODIFICATION OR DISTRIBUTION OF THIS SOFTWARE IS SOLELY AT THE USERS OWN
 * RISK. IN NO EVENT SHALL AGERE SYSTEMS INC. OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, INCLUDING, BUT NOT LIMITED TO, CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 *
 ******************************************************************************/

/*******************************************************************************
 *  include files
 ******************************************************************************/
#include <linux/string.h>
#include <wl_version.h>

#include <debug.h>
#include <hcf.h>

#include <wl_enc.h>




/*******************************************************************************
 *  global definitions
 ******************************************************************************/
#if DBG

extern dbg_info_t *DbgInfo;

#endif  /* DBG */




/*******************************************************************************
 *	wl_wep_code()
 *******************************************************************************
 *
 *  DESCRIPTION:
 *
 *      This function encodes a set of wep keys for privacy
 *
 *  PARAMETERS:
 *
 *      szCrypt -
 *      szDest  -
 *      Data    -
 *      nLen    -
 *
 *  RETURNS:
 *
 *      OK
 *
 ******************************************************************************/
int wl_wep_code(char *szCrypt, char *szDest, void *Data, int nLen)
{
	int     i;
	int     t;
	int     k ;
	char    bits;
	char    *szData = (char *) Data;
	/*------------------------------------------------------------------------*/


	for (i = bits = 0; i < MACADDRESS_STR_LEN; i++) {
		bits ^= szCrypt[i];
		bits += szCrypt[i];
	}

	for (i = t = *szDest = 0; i < nLen; i++, t++) {
		k = szData[i] ^ (bits + i);


	switch (i % 3) {

	case 0:

		szDest[t]   = ((k & 0xFC) >> 2) + CH_START ;
		szDest[t+1] = ((k & 0x03) << 4) + CH_START ;
		szDest[t+2] = '\0';

		break;


	case 1:

		szDest[t]  += ((k & 0xF0) >> 4);
		szDest[t+1] = ((k & 0x0F) << 2) + CH_START ;
		szDest[t+2] = '\0';

		break;


	case 2:

		szDest[t]  += ((k & 0xC0) >> 6);
		szDest[t+1] = (k & 0x3F) + CH_START ;
		szDest[t+2] = '\0';
		t++;

		break;
	}
	}

	return strlen(szDest);

}
/*============================================================================*/




/*******************************************************************************
 *	wl_wep_decode()
 *******************************************************************************
 *
 *  DESCRIPTION:
 *
 *      This function decodes a set of WEP keys for use by the card.
 *
 *  PARAMETERS:
 *
 *      szCrypt -
 *      szDest  -
 *      Data    -
 *
 *  RETURNS:
 *
 *      OK
 *
 ******************************************************************************/
int wl_wep_decode(char *szCrypt, void *Dest, char *szData)
{
	int     i;
	int     t;
	int     nLen;
	char    bits;
	char    *szDest = Dest;
	/*------------------------------------------------------------------------*/


	for (i = bits = 0; i < 12; i++) {
		bits ^= szCrypt[i] ;
		bits += szCrypt[i] ;
	}

	nLen = (strlen(szData) * 3) / 4 ;

	for (i = t = 0; i < nLen; i++, t++) {
		switch (i % 3) {
		case 0:

			szDest[i] = (((szData[t] - CH_START) & 0x3f) << 2) +
				    (((szData[t+1] - CH_START) & 0x30) >> 4);
			break;


		case 1:
			szDest[i] = (((szData[t] - CH_START) & 0x0f) << 4) +
				    (((szData[t+1] - CH_START) & 0x3c) >> 2);
			break;


		case 2:
			szDest[i] = (((szData[t] - CH_START) & 0x03) << 6) +
				     ((szData[t+1] - CH_START) & 0x3f);
			t++;
			break;
		}

		szDest[i] ^= (bits + i);

	}

	return i;

}
/*============================================================================*/