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