1/*	$KAME: des_setkey.c,v 1.7 2001/09/10 04:03:58 itojun Exp $	*/
2
3/* crypto/des/set_key.c */
4
5/* Copyright (C) 1995-1996 Eric Young (eay@mincom.oz.au)
6 * All rights reserved.
7 *
8 * This file is part of an SSL implementation written
9 * by Eric Young (eay@mincom.oz.au).
10 * The implementation was written so as to conform with Netscapes SSL
11 * specification.  This library and applications are
12 * FREE FOR COMMERCIAL AND NON-COMMERCIAL USE
13 * as long as the following conditions are aheared to.
14 *
15 * Copyright remains Eric Young's, and as such any Copyright notices in
16 * the code are not to be removed.  If this code is used in a product,
17 * Eric Young should be given attribution as the author of the parts used.
18 * This can be in the form of a textual message at program startup or
19 * in documentation (online or textual) provided with the package.
20 *
21 * Redistribution and use in source and binary forms, with or without
22 * modification, are permitted provided that the following conditions
23 * are met:
24 * 1. Redistributions of source code must retain the copyright
25 *    notice, this list of conditions and the following disclaimer.
26 * 2. Redistributions in binary form must reproduce the above copyright
27 *    notice, this list of conditions and the following disclaimer in the
28 *    documentation and/or other materials provided with the distribution.
29 * 3. All advertising materials mentioning features or use of this software
30 *    must display the following acknowledgement:
31 *    This product includes software developed by Eric Young (eay@mincom.oz.au)
32 *
33 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
34 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
35 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
36 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
37 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
38 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
39 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
41 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
42 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
43 * SUCH DAMAGE.
44 *
45 * The licence and distribution terms for any publically available version or
46 * derivative of this code cannot be changed.  i.e. this code cannot simply be
47 * copied and put under another distribution licence
48 * [including the GNU Public Licence.]
49 */
50
51/* set_key.c v 1.4 eay 24/9/91
52 * 1.4 Speed up by 400% :-)
53 * 1.3 added register declarations.
54 * 1.2 unrolled make_key_sched a bit more
55 * 1.1 added norm_expand_bits
56 * 1.0 First working version
57 */
58
59#include <sys/cdefs.h>
60__FBSDID("$FreeBSD$");
61
62#include <sys/param.h>
63#include <sys/systm.h>
64#include <crypto/des/des_locl.h>
65#include <crypto/des/podd.h>
66#include <crypto/des/sk.h>
67
68int des_check_key=0;
69
70void des_set_odd_parity(des_cblock *key)
71{
72	int i;
73
74	for (i=0; i<DES_KEY_SZ; i++)
75		(*key)[i]=odd_parity[(*key)[i]];
76}
77
78int des_check_key_parity(des_cblock *key)
79{
80	int i;
81
82	for (i=0; i<DES_KEY_SZ; i++)
83		{
84		if ((*key)[i] != odd_parity[(*key)[i]])
85			return(0);
86		}
87	return(1);
88}
89
90/* Weak and semi week keys as take from
91 * %A D.W. Davies
92 * %A W.L. Price
93 * %T Security for Computer Networks
94 * %I John Wiley & Sons
95 * %D 1984
96 * Many thanks to smb@ulysses.att.com (Steven Bellovin) for the reference
97 * (and actual cblock values).
98 */
99#define NUM_WEAK_KEY	16
100static des_cblock weak_keys[NUM_WEAK_KEY]={
101	/* weak keys */
102	{0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01},
103	{0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE},
104	{0x1F,0x1F,0x1F,0x1F,0x0E,0x0E,0x0E,0x0E},
105	{0xE0,0xE0,0xE0,0xE0,0xF1,0xF1,0xF1,0xF1},
106	/* semi-weak keys */
107	{0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE},
108	{0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01},
109	{0x1F,0xE0,0x1F,0xE0,0x0E,0xF1,0x0E,0xF1},
110	{0xE0,0x1F,0xE0,0x1F,0xF1,0x0E,0xF1,0x0E},
111	{0x01,0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1},
112	{0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1,0x01},
113	{0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E,0xFE},
114	{0xFE,0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E},
115	{0x01,0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E},
116	{0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E,0x01},
117	{0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1,0xFE},
118	{0xFE,0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1}};
119
120int des_is_weak_key(des_cblock *key)
121{
122	int i;
123
124	for (i=0; i<NUM_WEAK_KEY; i++)
125		/* Added == 0 to comparison, I obviously don't run
126		 * this section very often :-(, thanks to
127		 * engineering@MorningStar.Com for the fix
128		 * eay 93/06/29
129		 * Another problem, I was comparing only the first 4
130		 * bytes, 97/03/18 */
131		if (memcmp(weak_keys[i],key,sizeof(des_cblock)) == 0) return(1);
132	return(0);
133}
134
135/* NOW DEFINED IN des_local.h
136 * See ecb_encrypt.c for a pseudo description of these macros.
137 * #define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\
138 * 	(b)^=(t),\
139 * 	(a)=((a)^((t)<<(n))))
140 */
141
142#define HPERM_OP(a,t,n,m) ((t)=((((a)<<(16-(n)))^(a))&(m)),\
143	(a)=(a)^(t)^(t>>(16-(n))))
144
145int des_set_key(des_cblock *key, des_key_schedule schedule)
146{
147	if (des_check_key)
148	{
149		return des_set_key_checked(key, schedule);
150	}
151	else
152	{
153		des_set_key_unchecked(key, schedule);
154		return 0;
155	}
156}
157
158/* return 0 if key parity is odd (correct),
159 * return -1 if key parity error,
160 * return -2 if illegal weak key.
161 */
162int des_set_key_checked(des_cblock *key, des_key_schedule schedule)
163{
164	if (!des_check_key_parity(key))
165		return(-1);
166	if (des_is_weak_key(key))
167		return(-2);
168	des_set_key_unchecked(key, schedule);
169	return 0;
170}
171
172void des_set_key_unchecked(des_cblock *key, des_key_schedule schedule)
173{
174	static int shifts2[16]={0,0,1,1,1,1,1,1,0,1,1,1,1,1,1,0};
175	register DES_LONG c,d,t,s,t2;
176	register const unsigned char *in;
177	register DES_LONG *k;
178	register int i;
179
180	k = &schedule->ks.deslong[0];
181	in = &(*key)[0];
182
183	c2l(in,c);
184	c2l(in,d);
185
186	/* do PC1 in 47 simple operations :-)
187	 * Thanks to John Fletcher (john_fletcher@lccmail.ocf.llnl.gov)
188	 * for the inspiration. :-) */
189	PERM_OP (d,c,t,4,0x0f0f0f0fL);
190	HPERM_OP(c,t,-2,0xcccc0000L);
191	HPERM_OP(d,t,-2,0xcccc0000L);
192	PERM_OP (d,c,t,1,0x55555555L);
193	PERM_OP (c,d,t,8,0x00ff00ffL);
194	PERM_OP (d,c,t,1,0x55555555L);
195	d=	(((d&0x000000ffL)<<16L)| (d&0x0000ff00L)     |
196		 ((d&0x00ff0000L)>>16L)|((c&0xf0000000L)>>4L));
197	c&=0x0fffffffL;
198
199	for (i=0; i<ITERATIONS; i++)
200	{
201		if (shifts2[i])
202			{ c=((c>>2L)|(c<<26L)); d=((d>>2L)|(d<<26L)); }
203		else
204			{ c=((c>>1L)|(c<<27L)); d=((d>>1L)|(d<<27L)); }
205		c&=0x0fffffffL;
206		d&=0x0fffffffL;
207		/* could be a few less shifts but I am to lazy at this
208	 	* point in time to investigate */
209		s=	des_skb[0][ (c    )&0x3f                ]|
210			des_skb[1][((c>> 6L)&0x03)|((c>> 7L)&0x3c)]|
211			des_skb[2][((c>>13L)&0x0f)|((c>>14L)&0x30)]|
212			des_skb[3][((c>>20L)&0x01)|((c>>21L)&0x06) |
213						  	((c>>22L)&0x38)];
214		t=	des_skb[4][ (d    )&0x3f                ]|
215			des_skb[5][((d>> 7L)&0x03)|((d>> 8L)&0x3c)]|
216			des_skb[6][ (d>>15L)&0x3f                ]|
217			des_skb[7][((d>>21L)&0x0f)|((d>>22L)&0x30)];
218
219		/* table contained 0213 4657 */
220		t2=((t<<16L)|(s&0x0000ffffL))&0xffffffffL;
221		*(k++)=ROTATE(t2,30)&0xffffffffL;
222
223		t2=((s>>16L)|(t&0xffff0000L));
224		*(k++)=ROTATE(t2,26)&0xffffffffL;
225	}
226}
227
228int des_key_sched(des_cblock *key, des_key_schedule schedule)
229{
230	return(des_set_key(key,schedule));
231}
232
233void des_fixup_key_parity(des_cblock *key)
234{
235	des_set_odd_parity(key);
236}
237