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/param.h> 60 #include <sys/systm.h> 61 #include <crypto/des/des_locl.h> 62 #include <crypto/des/podd.h> 63 #include <crypto/des/sk.h> 64 65 int des_check_key=0; 66 67 void des_set_odd_parity(unsigned char *key) 68 { 69 int i; 70 71 for (i=0; i<DES_KEY_SZ; i++) 72 key[i]=odd_parity[key[i]]; 73 } 74 75 int des_check_key_parity(const unsigned char *key) 76 { 77 int i; 78 79 for (i=0; i<DES_KEY_SZ; i++) 80 { 81 if (key[i] != odd_parity[key[i]]) 82 return(0); 83 } 84 return(1); 85 } 86 87 /* Weak and semi week keys as take from 88 * %A D.W. Davies 89 * %A W.L. Price 90 * %T Security for Computer Networks 91 * %I John Wiley & Sons 92 * %D 1984 93 * Many thanks to smb@ulysses.att.com (Steven Bellovin) for the reference 94 * (and actual cblock values). 95 */ 96 #define NUM_WEAK_KEY 16 97 static des_cblock weak_keys[NUM_WEAK_KEY]={ 98 /* weak keys */ 99 {0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01}, 100 {0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE}, 101 {0x1F,0x1F,0x1F,0x1F,0x0E,0x0E,0x0E,0x0E}, 102 {0xE0,0xE0,0xE0,0xE0,0xF1,0xF1,0xF1,0xF1}, 103 /* semi-weak keys */ 104 {0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE}, 105 {0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01}, 106 {0x1F,0xE0,0x1F,0xE0,0x0E,0xF1,0x0E,0xF1}, 107 {0xE0,0x1F,0xE0,0x1F,0xF1,0x0E,0xF1,0x0E}, 108 {0x01,0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1}, 109 {0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1,0x01}, 110 {0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E,0xFE}, 111 {0xFE,0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E}, 112 {0x01,0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E}, 113 {0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E,0x01}, 114 {0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1,0xFE}, 115 {0xFE,0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1}}; 116 117 int des_is_weak_key(const unsigned char *key) 118 { 119 int i; 120 121 for (i=0; i<NUM_WEAK_KEY; i++) 122 /* Added == 0 to comparison, I obviously don't run 123 * this section very often :-(, thanks to 124 * engineering@MorningStar.Com for the fix 125 * eay 93/06/29 126 * Another problem, I was comparing only the first 4 127 * bytes, 97/03/18 */ 128 if (memcmp(weak_keys[i],key,sizeof(des_cblock)) == 0) return(1); 129 return(0); 130 } 131 132 /* NOW DEFINED IN des_local.h 133 * See ecb_encrypt.c for a pseudo description of these macros. 134 * #define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\ 135 * (b)^=(t),\ 136 * (a)=((a)^((t)<<(n)))) 137 */ 138 139 #define HPERM_OP(a,t,n,m) ((t)=((((a)<<(16-(n)))^(a))&(m)),\ 140 (a)=(a)^(t)^(t>>(16-(n)))) 141 142 int des_set_key(const unsigned char *key, des_key_schedule schedule) 143 { 144 if (des_check_key) 145 { 146 return des_set_key_checked(key, schedule); 147 } 148 else 149 { 150 des_set_key_unchecked(key, schedule); 151 return 0; 152 } 153 } 154 155 /* return 0 if key parity is odd (correct), 156 * return -1 if key parity error, 157 * return -2 if illegal weak key. 158 */ 159 int des_set_key_checked(const unsigned char *key, des_key_schedule schedule) 160 { 161 if (!des_check_key_parity(key)) 162 return(-1); 163 if (des_is_weak_key(key)) 164 return(-2); 165 des_set_key_unchecked(key, schedule); 166 return 0; 167 } 168 169 void des_set_key_unchecked(const unsigned char *key, des_key_schedule schedule) 170 { 171 static int shifts2[16]={0,0,1,1,1,1,1,1,0,1,1,1,1,1,1,0}; 172 DES_LONG c,d,t,s,t2; 173 const unsigned char *in; 174 DES_LONG *k; 175 int i; 176 177 k = &schedule->ks.deslong[0]; 178 in = key; 179 180 c2l(in,c); 181 c2l(in,d); 182 183 /* do PC1 in 47 simple operations :-) 184 * Thanks to John Fletcher (john_fletcher@lccmail.ocf.llnl.gov) 185 * for the inspiration. :-) */ 186 PERM_OP (d,c,t,4,0x0f0f0f0fL); 187 HPERM_OP(c,t,-2,0xcccc0000L); 188 HPERM_OP(d,t,-2,0xcccc0000L); 189 PERM_OP (d,c,t,1,0x55555555L); 190 PERM_OP (c,d,t,8,0x00ff00ffL); 191 PERM_OP (d,c,t,1,0x55555555L); 192 d= (((d&0x000000ffL)<<16L)| (d&0x0000ff00L) | 193 ((d&0x00ff0000L)>>16L)|((c&0xf0000000L)>>4L)); 194 c&=0x0fffffffL; 195 196 for (i=0; i<ITERATIONS; i++) 197 { 198 if (shifts2[i]) 199 { c=((c>>2L)|(c<<26L)); d=((d>>2L)|(d<<26L)); } 200 else 201 { c=((c>>1L)|(c<<27L)); d=((d>>1L)|(d<<27L)); } 202 c&=0x0fffffffL; 203 d&=0x0fffffffL; 204 /* could be a few less shifts but I am to lazy at this 205 * point in time to investigate */ 206 s= des_skb[0][ (c )&0x3f ]| 207 des_skb[1][((c>> 6L)&0x03)|((c>> 7L)&0x3c)]| 208 des_skb[2][((c>>13L)&0x0f)|((c>>14L)&0x30)]| 209 des_skb[3][((c>>20L)&0x01)|((c>>21L)&0x06) | 210 ((c>>22L)&0x38)]; 211 t= des_skb[4][ (d )&0x3f ]| 212 des_skb[5][((d>> 7L)&0x03)|((d>> 8L)&0x3c)]| 213 des_skb[6][ (d>>15L)&0x3f ]| 214 des_skb[7][((d>>21L)&0x0f)|((d>>22L)&0x30)]; 215 216 /* table contained 0213 4657 */ 217 t2=((t<<16L)|(s&0x0000ffffL))&0xffffffffL; 218 *(k++)=ROTATE(t2,30)&0xffffffffL; 219 220 t2=((s>>16L)|(t&0xffff0000L)); 221 *(k++)=ROTATE(t2,26)&0xffffffffL; 222 } 223 } 224 225 int des_key_sched(const unsigned char *key, des_key_schedule schedule) 226 { 227 return(des_set_key(key,schedule)); 228 } 229 230 void des_fixup_key_parity(unsigned char *key) 231 { 232 des_set_odd_parity(key); 233 } 234