str2key.c

IP网络语音通讯软件源代码. 不可多得的语音源代码

/* lib/des/str2key.c */
/* Copyright (C) 1995 Eric Young ([e-mail])
 * All rights reserved.
 * 
 * This file is part of an SSL implementation written
 * by Eric Young ([e-mail]).
 * The implementation was written so as to conform with Netscapes SSL
 * specification.  This library and applications are
 * FREE FOR COMMERCIAL AND NON-COMMERCIAL USE
 * as long as the following conditions are aheared to.
 * 
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.	If this code is used in a product,
 * Eric Young should be given attribution as the author of the parts used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *	  notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. All advertising materials mentioning features or use of this software
 *	  must display the following acknowledgement:
 *	  This product includes software developed by Eric Young ([e-mail])
 * 
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.	IN NO EVENT SHALL THE AUTHOR 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, WHETHER IN 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.
 * 
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#include "des_locl.h"

extern int des_check_key;

void des_string_to_key(str, key)
char FAR *str;
des_cblock (FAR *key);
		{
		des_key_schedule ks;
		int i,length;
		register unsigned char j;

		_fmemset(key,0,8);
		length=_fstrlen(str);
#ifdef OLD_STR_TO_KEY
		for (i=0; i<length; i++)
				(*key)[i%8]^=(str[i]<<1);
#else /* MIT COMPATIBLE */
		for (i=0; i<length; i++)
				{
				j=str[i];
				if ((i%16) < 8)
						(*key)[i%8]^=(j<<1);
				else
						{
						/* Reverse the bit order 05/05/92 eay */
						j=((j<<4)&0xf0)|((j>>4)&0x0f);
						j=((j<<2)&0xcc)|((j>>2)&0x33);
						j=((j<<1)&0xaa)|((j>>1)&0x55);
						(*key)[7-(i%8)]^=j;
						}
				}
#endif
		des_set_odd_parity((des_cblock FAR *)key);
		i=des_check_key;
		des_check_key=0;
		des_set_key((des_cblock FAR *)key,ks);
		des_check_key=i;
		des_cbc_cksum((des_cblock FAR *)str,(des_cblock FAR *)key,(long)length,ks,
				(des_cblock FAR *)key);
		memset(ks,0,sizeof(ks));
		des_set_odd_parity((des_cblock FAR *)key);
		}

#ifdef NEEDED
void des_string_to_2keys(str, key1, key2)
char *str;
des_cblock (*key1);
des_cblock (*key2);
		{
		des_key_schedule ks;
		int i,length;
		register unsigned char j;

		memset(key1,0,8);
		memset(key2,0,8);
		length=strlen(str);
#ifdef OLD_STR_TO_KEY
		if (length <= 8)
				{
				for (i=0; i<length; i++)
						{
						(*key2)[i]=(*key1)[i]=(str[i]<<1);
						}
				}
		else
				{
				for (i=0; i<length; i++)
						{
						if ((i/8)&1)
								(*key2)[i%8]^=(str[i]<<1);
						else
								(*key1)[i%8]^=(str[i]<<1);
						}
				}
#else /* MIT COMPATIBLE */
		for (i=0; i<length; i++)
				{
				j=str[i];
				if ((i%32) < 16)
						{
						if ((i%16) < 8)
								(*key1)[i%8]^=(j<<1);
						else
								(*key2)[i%8]^=(j<<1);
						}
				else
						{
						j=((j<<4)&0xf0)|((j>>4)&0x0f);
						j=((j<<2)&0xcc)|((j>>2)&0x33);
						j=((j<<1)&0xaa)|((j>>1)&0x55);
						if ((i%16) < 8)
								(*key1)[7-(i%8)]^=j;
						else
								(*key2)[7-(i%8)]^=j;
						}
				}
		if (length <= 8) memcpy(key2,key1,8);
#endif
		des_set_odd_parity((des_cblock *)key1);
		des_set_odd_parity((des_cblock *)key2);
		i=des_check_key;
		des_check_key=0;
		des_set_key((des_cblock *)key1,ks);
		des_cbc_cksum((des_cblock *)str,(des_cblock *)key1,(long)length,ks,
				(des_cblock *)key1);
		des_set_key((des_cblock *)key2,ks);
		des_cbc_cksum((des_cblock *)str,(des_cblock *)key2,(long)length,ks,
				(des_cblock *)key2);
		des_check_key=i;
		memset(ks,0,sizeof(ks));
		des_set_odd_parity(key1);
		des_set_odd_parity(key2);
		}
#endif