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 68 int des_check_key=0; 69 70 void des_set_odd_parity(unsigned char *key) 71 { 72 int i; 73 74 for (i=0; i<DES_KEY_SZ; i++) 75 key[i]=odd_parity[key[i]]; 76 } 77 78 int des_check_key_parity(const unsigned char *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 16 100 static 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}}; 119 120 int des_is_weak_key(const unsigned char *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)))) 144 145 int des_set_key(const unsigned char *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 */ 162 int des_set_key_checked(const unsigned char *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 } 171 172 void des_set_key_unchecked(const unsigned char *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 DES_LONG c,d,t,s,t2; 176 const unsigned char *in; 177 DES_LONG *k; 178 int i; 179 180 k = &schedule->ks.deslong[0]; 181 in = key; 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 } 227 228 int des_key_sched(const unsigned char *key, des_key_schedule schedule) 229 { 230 return(des_set_key(key,schedule)); 231 } 232 233 void des_fixup_key_parity(unsigned char *key) 234 { 235 des_set_odd_parity(key); 236 } 237