set_key.c

/* crypto/des/set_key.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 * 
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 * 
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library 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 cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from 
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 * 
 * 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.]
 */

/* set_key.c v 1.4 eay 24/9/91
 * 1.4 Speed up by 400% :-)
 * 1.3 added register declarations.
 * 1.2 unrolled make_key_sched a bit more
 * 1.1 added norm_expand_bits
 * 1.0 First working version
 */
#include "des_locl.h"

OPENSSL_IMPLEMENT_GLOBAL(int,des_check_key);	/* defaults to false */

static const unsigned char odd_parity[256]={
  1,  1,  2,  2,  4,  4,  7,  7,  8,  8, 11, 11, 13, 13, 14, 14,
 16, 16, 19, 19, 21, 21, 22, 22, 25, 25, 26, 26, 28, 28, 31, 31,
 32, 32, 35, 35, 37, 37, 38, 38, 41, 41, 42, 42, 44, 44, 47, 47,
 49, 49, 50, 50, 52, 52, 55, 55, 56, 56, 59, 59, 61, 61, 62, 62,
 64, 64, 67, 67, 69, 69, 70, 70, 73, 73, 74, 74, 76, 76, 79, 79,
 81, 81, 82, 82, 84, 84, 87, 87, 88, 88, 91, 91, 93, 93, 94, 94,
 97, 97, 98, 98,100,100,103,103,104,104,107,107,109,109,110,110,
112,112,115,115,117,117,118,118,121,121,122,122,124,124,127,127,
128,128,131,131,133,133,134,134,137,137,138,138,140,140,143,143,
145,145,146,146,148,148,151,151,152,152,155,155,157,157,158,158,
161,161,162,162,164,164,167,167,168,168,171,171,173,173,174,174,
176,176,179,179,181,181,182,182,185,185,186,186,188,188,191,191,
193,193,194,194,196,196,199,199,200,200,203,203,205,205,206,206,
208,208,211,211,213,213,214,214,217,217,218,218,220,220,223,223,
224,224,227,227,229,229,230,230,233,233,234,234,236,236,239,239,
241,241,242,242,244,244,247,247,248,248,251,251,253,253,254,254};

void des_set_odd_parity(des_cblock *key)
	{
	int i;

	for (i=0; i<DES_KEY_SZ; i++)
		(*key)[i]=odd_parity[(*key)[i]];
	}

int des_check_key_parity(const_des_cblock *key)
	{
	int i;

	for (i=0; i<DES_KEY_SZ; i++)
		{
		if ((*key)[i] != odd_parity[(*key)[i]])
			return(0);
		}
	return(1);
	}

/* Weak and semi week keys as take from
 * %A D.W. Davies
 * %A W.L. Price
 * %T Security for Computer Networks
 * %I John Wiley & Sons
 * %D 1984
 * Many thanks to smb@ulysses.att.com (Steven Bellovin) for the reference
 * (and actual cblock values).
 */
#define NUM_WEAK_KEY	16
static des_cblock weak_keys[NUM_WEAK_KEY]={
	/* weak keys */
	{0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01},
	{0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE},
	{0x1F,0x1F,0x1F,0x1F,0x0E,0x0E,0x0E,0x0E},
	{0xE0,0xE0,0xE0,0xE0,0xF1,0xF1,0xF1,0xF1},
	/* semi-weak keys */
	{0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE},
	{0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01},
	{0x1F,0xE0,0x1F,0xE0,0x0E,0xF1,0x0E,0xF1},
	{0xE0,0x1F,0xE0,0x1F,0xF1,0x0E,0xF1,0x0E},
	{0x01,0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1},
	{0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1,0x01},
	{0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E,0xFE},
	{0xFE,0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E},
	{0x01,0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E},
	{0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E,0x01},
	{0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1,0xFE},
	{0xFE,0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1}};

int des_is_weak_key(const_des_cblock *key)
	{
	int i;

	for (i=0; i<NUM_WEAK_KEY; i++)
		/* Added == 0 to comparison, I obviously don't run
		 * this section very often :-(, thanks to
		 * engineering@MorningStar.Com for the fix
		 * eay 93/06/29
		 * Another problem, I was comparing only the first 4
		 * bytes, 97/03/18 */
		if (memcmp(weak_keys[i],key,sizeof(des_cblock)) == 0) return(1);
	return(0);
	}

/* NOW DEFINED IN des_local.h
 * See ecb_encrypt.c for a pseudo description of these macros. 
 * #define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\
 * 	(b)^=(t),\
 * 	(a)=((a)^((t)<<(n))))
 */

#define HPERM_OP(a,t,n,m) ((t)=((((a)<<(16-(n)))^(a))&(m)),\
	(a)=(a)^(t)^(t>>(16-(n))))

static const DES_LONG des_skb[8][64]={
	{
	/* for C bits (numbered as per FIPS 46) 1 2 3 4 5 6 */
	0x00000000L,0x00000010L,0x20000000L,0x20000010L,
	0x00010000L,0x00010010L,0x20010000L,0x20010010L,
	0x00000800L,0x00000810L,0x20000800L,0x20000810L,
	0x00010800L,0x00010810L,0x20010800L,0x20010810L,
	0x00000020L,0x00000030L,0x20000020L,0x20000030L,
	0x00010020L,0x00010030L,0x20010020L,0x20010030L,
	0x00000820L,0x00000830L,0x20000820L,0x20000830L,
	0x00010820L,0x00010830L,0x20010820L,0x20010830L,
	0x00080000L,0x00080010L,0x20080000L,0x20080010L,
	0x00090000L,0x00090010L,0x20090000L,0x20090010L,
	0x00080800L,0x00080810L,0x20080800L,0x20080810L,
	0x00090800L,0x00090810L,0x20090800L,0x20090810L,
	0x00080020L,0x00080030L,0x20080020L,0x20080030L,
	0x00090020L,0x00090030L,0x20090020L,0x20090030L,
	0x00080820L,0x00080830L,0x20080820L,0x20080830L,
	0x00090820L,0x00090830L,0x20090820L,0x20090830L,
	},{
	/* for C bits (numbered as per FIPS 46) 7 8 10 11 12 13 */
	0x00000000L,0x02000000L,0x00002000L,0x02002000L,
	0x00200000L,0x02200000L,0x00202000L,0x02202000L,
	0x00000004L,0x02000004L,0x00002004L,0x02002004L,
	0x00200004L,0x02200004L,0x00202004L,0x02202004L,
	0x00000400L,0x02000400L,0x00002400L,0x02002400L,
	0x00200400L,0x02200400L,0x00202400L,0x02202400L,
	0x00000404L,0x02000404L,0x00002404L,0x02002404L,
	0x00200404L,0x02200404L,0x00202404L,0x02202404L,
	0x10000000L,0x12000000L,0x10002000L,0x12002000L,
	0x10200000L,0x12200000L,0x10202000L,0x12202000L,
	0x10000004L,0x12000004L,0x10002004L,0x12002004L,
	0x10200004L,0x12200004L,0x10202004L,0x12202004L,
	0x10000400L,0x12000400L,0x10002400L,0x12002400L,
	0x10200400L,0x12200400L,0x10202400L,0x12202400L,
	0x10000404L,0x12000404L,0x10002404L,0x12002404L,
	0x10200404L,0x12200404L,0x10202404L,0x12202404L,
	},{
	/* for C bits (numbered as per FIPS 46) 14 15 16 17 19 20 */
	0x00000000L,0x00000001L,0x00040000L,0x00040001L,
	0x01000000L,0x01000001L,0x01040000L,0x01040001L,
	0x00000002L,0x00000003L,0x00040002L,0x00040003L,
	0x01000002L,0x01000003L,0x01040002L,0x01040003L,
	0x00000200L,0x00000201L,0x00040200L,0x00040201L,
	0x01000200L,0x01000201L,0x01040200L,0x01040201L,
	0x00000202L,0x00000203L,0x00040202L,0x00040203L,
	0x01000202L,0x01000203L,0x01040202L,0x01040203L,
	0x08000000L,0x08000001L,0x08040000L,0x08040001L,
	0x09000000L,0x09000001L,0x09040000L,0x09040001L,
	0x08000002L,0x08000003L,0x08040002L,0x08040003L,
	0x09000002L,0x09000003L,0x09040002L,0x09040003L,
	0x08000200L,0x08000201L,0x08040200L,0x08040201L,
	0x09000200L,0x09000201L,0x09040200L,0x09040201L,
	0x08000202L,0x08000203L,0x08040202L,0x08040203L,
	0x09000202L,0x09000203L,0x09040202L,0x09040203L,
	},{
	/* for C bits (numbered as per FIPS 46) 21 23 24 26 27 28 */
	0x00000000L,0x00100000L,0x00000100L,0x00100100L,
	0x00000008L,0x00100008L,0x00000108L,0x00100108L,
	0x00001000L,0x00101000L,0x00001100L,0x00101100L,
	0x00001008L,0x00101008L,0x00001108L,0x00101108L,
	0x04000000L,0x04100000L,0x04000100L,0x04100100L,
	0x04000008L,0x04100008L,0x04000108L,0x04100108L,
	0x04001000L,0x04101000L,0x04001100L,0x04101100L,
	0x04001008L,0x04101008L,0x04001108L,0x04101108L,
	0x00020000L,0x00120000L,0x00020100L,0x00120100L,
	0x00020008L,0x00120008L,0x00020108L,0x00120108L,
	0x00021000L,0x00121000L,0x00021100L,0x00121100L,
	0x00021008L,0x00121008L,0x00021108L,0x00121108L,
	0x04020000L,0x04120000L,0x04020100L,0x04120100L,
	0x04020008L,0x04120008L,0x04020108L,0x04120108L,
	0x04021000L,0x04121000L,0x04021100L,0x04121100L,
	0x04021008L,0x04121008L,0x04021108L,0x04121108L,
	},{
	/* for D bits (numbered as per FIPS 46) 1 2 3 4 5 6 */
	0x00000000L,0x10000000L,0x00010000L,0x10010000L,
	0x00000004L,0x10000004L,0x00010004L,0x10010004L,
	0x20000000L,0x30000000L,0x20010000L,0x30010000L,
	0x20000004L,0x30000004L,0x20010004L,0x30010004L,
	0x00100000L,0x10100000L,0x00110000L,0x10110000L,
	0x00100004L,0x10100004L,0x00110004L,0x10110004L,
	0x20100000L,0x30100000L,0x20110000L,0x30110000L,
	0x20100004L,0x30100004L,0x20110004L,0x30110004L,
	0x00001000L,0x10001000L,0x00011000L,0x10011000L,
	0x00001004L,0x10001004L,0x00011004L,0x10011004L,
	0x20001000L,0x30001000L,0x20011000L,0x30011000L,
	0x20001004L,0x30001004L,0x20011004L,0x30011004L,
	0x00101000L,0x10101000L,0x00111000L,0x10111000L,
	0x00101004L,0x10101004L,0x00111004L,0x10111004L,
	0x20101000L,0x30101000L,0x20111000L,0x30111000L,
	0x20101004L,0x30101004L,0x20111004L,0x30111004L,
	},{
	/* for D bits (numbered as per FIPS 46) 8 9 11 12 13 14 */
	0x00000000L,0x08000000L,0x00000008L,0x08000008L,
	0x00000400L,0x08000400L,0x00000408L,0x08000408L,
	0x00020000L,0x08020000L,0x00020008L,0x08020008L,
	0x00020400L,0x08020400L,0x00020408L,0x08020408L,
	0x00000001L,0x08000001L,0x00000009L,0x08000009L,
	0x00000401L,0x08000401L,0x00000409L,0x08000409L,
	0x00020001L,0x08020001L,0x00020009L,0x08020009L,
	0x00020401L,0x08020401L,0x00020409L,0x08020409L,
	0x02000000L,0x0A000000L,0x02000008L,0x0A000008L,
	0x02000400L,0x0A000400L,0x02000408L,0x0A000408L,
	0x02020000L,0x0A020000L,0x02020008L,0x0A020008L,
	0x02020400L,0x0A020400L,0x02020408L,0x0A020408L,
	0x02000001L,0x0A000001L,0x02000009L,0x0A000009L,
	0x02000401L,0x0A000401L,0x02000409L,0x0A000409L,
	0x02020001L,0x0A020001L,0x02020009L,0x0A020009L,
	0x02020401L,0x0A020401L,0x02020409L,0x0A020409L,
	},{
	/* for D bits (numbered as per FIPS 46) 16 17 18 19 20 21 */
	0x00000000L,0x00000100L,0x00080000L,0x00080100L,
	0x01000000L,0x01000100L,0x01080000L,0x01080100L,
	0x00000010L,0x00000110L,0x00080010L,0x00080110L,
	0x01000010L,0x01000110L,0x01080010L,0x01080110L,
	0x00200000L,0x00200100L,0x00280000L,0x00280100L,
	0x01200000L,0x01200100L,0x01280000L,0x01280100L,
	0x00200010L,0x00200110L,0x00280010L,0x00280110L,
	0x01200010L,0x01200110L,0x01280010L,0x01280110L,
	0x00000200L,0x00000300L,0x00080200L,0x00080300L,
	0x01000200L,0x01000300L,0x01080200L,0x01080300L,
	0x00000210L,0x00000310L,0x00080210L,0x00080310L,
	0x01000210L,0x01000310L,0x01080210L,0x01080310L,
	0x00200200L,0x00200300L,0x00280200L,0x00280300L,
	0x01200200L,0x01200300L,0x01280200L,0x01280300L,
	0x00200210L,0x00200310L,0x00280210L,0x00280310L,
	0x01200210L,0x01200310L,0x01280210L,0x01280310L,
	},{
	/* for D bits (numbered as per FIPS 46) 22 23 24 25 27 28 */
	0x00000000L,0x04000000L,0x00040000L,0x04040000L,
	0x00000002L,0x04000002L,0x00040002L,0x04040002L,
	0x00002000L,0x04002000L,0x00042000L,0x04042000L,
	0x00002002L,0x04002002L,0x00042002L,0x04042002L,
	0x00000020L,0x04000020L,0x00040020L,0x04040020L,
	0x00000022L,0x04000022L,0x00040022L,0x04040022L,
	0x00002020L,0x04002020L,0x00042020L,0x04042020L,
	0x00002022L,0x04002022L,0x00042022L,0x04042022L,
	0x00000800L,0x04000800L,0x00040800L,0x04040800L,
	0x00000802L,0x04000802L,0x00040802L,0x04040802L,
	0x00002800L,0x04002800L,0x00042800L,0x04042800L,
	0x00002802L,0x04002802L,0x00042802L,0x04042802L,
	0x00000820L,0x04000820L,0x00040820L,0x04040820L,
	0x00000822L,0x04000822L,0x00040822L,0x04040822L,
	0x00002820L,0x04002820L,0x00042820L,0x04042820L,
	0x00002822L,0x04002822L,0x00042822L,0x04042822L,
	}};

int des_set_key(const_des_cblock *key, des_key_schedule schedule)
	{
	if (des_check_key)
		{
		return des_set_key_checked(key, schedule);
		}
	else
		{
		des_set_key_unchecked(key, schedule);
		return 0;
		}
	}

/* return 0 if key parity is odd (correct),
 * return -1 if key parity error,
 * return -2 if illegal weak key.
 */
int des_set_key_checked(const_des_cblock *key, des_key_schedule schedule)
	{
	if (!des_check_key_parity(key))
		return(-1);
	if (des_is_weak_key(key))
		return(-2);
	des_set_key_unchecked(key, schedule);
	return 0;
	}

void des_set_key_unchecked(const_des_cblock *key, des_key_schedule schedule)
	{
	static int shifts2[16]={0,0,1,1,1,1,1,1,0,1,1,1,1,1,1,0};
	register DES_LONG c,d,t,s,t2;
	register const unsigned char *in;
	register DES_LONG *k;
	register int i;

	k = &schedule->ks.deslong[0];
	in = &(*key)[0];

	c2l(in,c);
	c2l(in,d);

	/* do PC1 in 47 simple operations :-)
	 * Thanks to John Fletcher (john_fletcher@lccmail.ocf.llnl.gov)
	 * for the inspiration. :-) */
	PERM_OP (d,c,t,4,0x0f0f0f0fL);
	HPERM_OP(c,t,-2,0xcccc0000L);
	HPERM_OP(d,t,-2,0xcccc0000L);
	PERM_OP (d,c,t,1,0x55555555L);
	PERM_OP (c,d,t,8,0x00ff00ffL);
	PERM_OP (d,c,t,1,0x55555555L);
	d=	(((d&0x000000ffL)<<16L)| (d&0x0000ff00L)     |
		 ((d&0x00ff0000L)>>16L)|((c&0xf0000000L)>>4L));
	c&=0x0fffffffL;

	for (i=0; i<ITERATIONS; i++)
		{
		if (shifts2[i])
			{ c=((c>>2L)|(c<<26L)); d=((d>>2L)|(d<<26L)); }
		else
			{ c=((c>>1L)|(c<<27L)); d=((d>>1L)|(d<<27L)); }
		c&=0x0fffffffL;
		d&=0x0fffffffL;
		/* could be a few less shifts but I am to lazy at this
		 * point in time to investigate */
		s=	des_skb[0][ (c    )&0x3f                ]|
			des_skb[1][((c>> 6L)&0x03)|((c>> 7L)&0x3c)]|
			des_skb[2][((c>>13L)&0x0f)|((c>>14L)&0x30)]|
			des_skb[3][((c>>20L)&0x01)|((c>>21L)&0x06) |
						  ((c>>22L)&0x38)];
		t=	des_skb[4][ (d    )&0x3f                ]|
			des_skb[5][((d>> 7L)&0x03)|((d>> 8L)&0x3c)]|
			des_skb[6][ (d>>15L)&0x3f                ]|
			des_skb[7][((d>>21L)&0x0f)|((d>>22L)&0x30)];

		/* table contained 0213 4657 */
		t2=((t<<16L)|(s&0x0000ffffL))&0xffffffffL;
		*(k++)=ROTATE(t2,30)&0xffffffffL;

		t2=((s>>16L)|(t&0xffff0000L));
		*(k++)=ROTATE(t2,26)&0xffffffffL;
		}
	}

int des_key_sched(const_des_cblock *key, des_key_schedule schedule)
	{
	return(des_set_key(key,schedule));
	}
/*
#undef des_fixup_key_parity
void des_fixup_key_parity(des_cblock *key)
	{
	des_set_odd_parity(key);
	}
*/