1/* $NetBSD: des_setkey.c,v 1.10 2005/12/11 12:20:52 christos Exp $ */
2/* $KAME: des_setkey.c,v 1.6 2001/07/03 14:27:53 itojun Exp $ */
3
4/* crypto/des/set_key.c */
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__KERNEL_RCSID(0, "$NetBSD: des_setkey.c,v 1.10 2005/12/11 12:20:52 christos Exp $");
61
62#include <sys/param.h>
63#ifdef _KERNEL
64#include <sys/systm.h>
65#else
66#include <string.h>
67#endif
68#include <crypto/des/des_locl.h>
69#include <crypto/des/podd.h>
70#include <crypto/des/sk.h>
71
72int des_check_key=0;
73
74void des_set_odd_parity(des_cblock *key)
75{
76 unsigned int i;
77
78 for (i=0; i<DES_KEY_SZ; i++)
79 (*key)[i]=odd_parity[(*key)[i]];
80}
81
82int des_check_key_parity(des_cblock *key)
83{
84 unsigned int i;
85
86 for (i=0; i<DES_KEY_SZ; i++)
87 {
88 if ((*key)[i] != odd_parity[(*key)[i]])
89 return(0);
90 }
91 return(1);
92}
93
94/* Weak and semi week keys as take from
95 * %A D.W. Davies
96 * %A W.L. Price
97 * %T Security for Computer Networks
98 * %I John Wiley & Sons
99 * %D 1984
100 * Many thanks to smb@ulysses.att.com (Steven Bellovin) for the reference
101 * (and actual cblock values).
102 */
103#define NUM_WEAK_KEY 16
104static des_cblock weak_keys[NUM_WEAK_KEY]={
105 /* weak keys */
106 {0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01},
107 {0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE},
108 {0x1F,0x1F,0x1F,0x1F,0x0E,0x0E,0x0E,0x0E},
109 {0xE0,0xE0,0xE0,0xE0,0xF1,0xF1,0xF1,0xF1},
110 /* semi-weak keys */
111 {0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE},
112 {0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01},
113 {0x1F,0xE0,0x1F,0xE0,0x0E,0xF1,0x0E,0xF1},
114 {0xE0,0x1F,0xE0,0x1F,0xF1,0x0E,0xF1,0x0E},
115 {0x01,0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1},
116 {0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1,0x01},
117 {0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E,0xFE},
118 {0xFE,0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E},
119 {0x01,0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E},
120 {0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E,0x01},
121 {0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1,0xFE},
122 {0xFE,0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1}};
123
124int des_is_weak_key(des_cblock *key)
125{
126 int i;
127
128 for (i=0; i<NUM_WEAK_KEY; i++)
129 /* Added == 0 to comparison, I obviously don't run
130 * this section very often :-(, thanks to
131 * engineering@MorningStar.Com for the fix
132 * eay 93/06/29
133 * Another problem, I was comparing only the first 4
134 * bytes, 97/03/18 */
135 if (memcmp(weak_keys[i],key,sizeof(des_cblock)) == 0) return(1);
136 return(0);
137}
138
139/* NOW DEFINED IN des_local.h
140 * See ecb_encrypt.c for a pseudo description of these macros.
141 * #define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\
142 * (b)^=(t),\
143 * (a)=((a)^((t)<<(n))))
144 */
145
146#define HPERM_OP(a,t,n,m) ((t)=((((a)<<(16-(n)))^(a))&(m)),\
147 (a)=(a)^(t)^(t>>(16-(n))))
148
149int des_set_key(des_cblock *key, des_key_schedule schedule)
150{
151 if (des_check_key)
152 {
153 return des_set_key_checked(key, schedule);
154 }
155 else
156 {
157 des_set_key_unchecked(key, schedule);
158 return 0;
159 }
160}
161
162/* return 0 if key parity is odd (correct),
163 * return -1 if key parity error,
164 * return -2 if illegal weak key.
165 */
166int des_set_key_checked(des_cblock *key, des_key_schedule schedule)
167{
168 if (!des_check_key_parity(key))
169 return(-1);
170 if (des_is_weak_key(key))
171 return(-2);
172 des_set_key_unchecked(key, schedule);
173 return 0;
174}
175
176void des_set_key_unchecked(des_cblock *key, des_key_schedule schedule)
177{
178 static int shifts2[16]={0,0,1,1,1,1,1,1,0,1,1,1,1,1,1,0};
179 register DES_LONG c,d,t,s,t2;
180 register const unsigned char *in;
181 register DES_LONG *k;
182 register int i;
183
184 k = &schedule->ks.deslong[0];
185 in = &(*key)[0];
186
187 c2l(in,c);
188 c2l(in,d);
189
190 /* do PC1 in 47 simple operations :-)
191 * Thanks to John Fletcher (john_fletcher@lccmail.ocf.llnl.gov)
192 * for the inspiration. :-) */
193 PERM_OP (d,c,t,4,0x0f0f0f0fL);
194 HPERM_OP(c,t,-2,0xcccc0000L);
195 HPERM_OP(d,t,-2,0xcccc0000L);
196 PERM_OP (d,c,t,1,0x55555555L);
197 PERM_OP (c,d,t,8,0x00ff00ffL);
198 PERM_OP (d,c,t,1,0x55555555L);
199 d= (((d&0x000000ffL)<<16L)| (d&0x0000ff00L) |
200 ((d&0x00ff0000L)>>16L)|((c&0xf0000000L)>>4L));
201 c&=0x0fffffffL;
202
203 for (i=0; i<ITERATIONS; i++)
204 {
205 if (shifts2[i])
206 { c=((c>>2L)|(c<<26L)); d=((d>>2L)|(d<<26L)); }
207 else
208 { c=((c>>1L)|(c<<27L)); d=((d>>1L)|(d<<27L)); }
209 c&=0x0fffffffL;
210 d&=0x0fffffffL;
211 /* could be a few less shifts but I am to lazy at this
212 * point in time to investigate */
213 s= des_skb[0][ (c )&0x3f ]|
214 des_skb[1][((c>> 6L)&0x03)|((c>> 7L)&0x3c)]|
215 des_skb[2][((c>>13L)&0x0f)|((c>>14L)&0x30)]|
216 des_skb[3][((c>>20L)&0x01)|((c>>21L)&0x06) |
217 ((c>>22L)&0x38)];
218 t= des_skb[4][ (d )&0x3f ]|
219 des_skb[5][((d>> 7L)&0x03)|((d>> 8L)&0x3c)]|
220 des_skb[6][ (d>>15L)&0x3f ]|
221 des_skb[7][((d>>21L)&0x0f)|((d>>22L)&0x30)];
222
223 /* table contained 0213 4657 */
224 t2=((t<<16L)|(s&0x0000ffffL))&0xffffffffL;
225 *(k++)=ROTATE(t2,30)&0xffffffffL;
226
227 t2=((s>>16L)|(t&0xffff0000L));
228 *(k++)=ROTATE(t2,26)&0xffffffffL;
229 }
230}
231
232int des_key_sched(des_cblock *key, des_key_schedule schedule)
233{
234 return(des_set_key(key,schedule));
235}
236
237void des_fixup_key_parity(des_cblock *key)
238{
239 des_set_odd_parity(key);
240}
241