1 /* $OpenBSD: set_key.c,v 1.2 2002/10/27 13:24:26 miod Exp $ */ 2 3 /* lib/des/set_key.c */ 4 /* Copyright (C) 1995 Eric Young (eay@mincom.oz.au) 5 * All rights reserved. 6 * 7 * This file is part of an SSL implementation written 8 * by Eric Young (eay@mincom.oz.au). 9 * The implementation was written so as to conform with Netscapes SSL 10 * specification. This library and applications are 11 * FREE FOR COMMERCIAL AND NON-COMMERCIAL USE 12 * as long as the following conditions are aheared to. 13 * 14 * Copyright remains Eric Young's, and as such any Copyright notices in 15 * the code are not to be removed. If this code is used in a product, 16 * Eric Young should be given attribution as the author of the parts used. 17 * This can be in the form of a textual message at program startup or 18 * in documentation (online or textual) provided with the package. 19 * 20 * Redistribution and use in source and binary forms, with or without 21 * modification, are permitted provided that the following conditions 22 * are met: 23 * 1. Redistributions of source code must retain the copyright 24 * notice, this list of conditions and the following disclaimer. 25 * 2. Redistributions in binary form must reproduce the above copyright 26 * notice, this list of conditions and the following disclaimer in the 27 * documentation and/or other materials provided with the distribution. 28 * 3. All advertising materials mentioning features or use of this software 29 * must display the following acknowledgement: 30 * This product includes software developed by Eric Young (eay@mincom.oz.au) 31 * 32 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 33 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 34 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 35 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 36 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 40 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 41 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 42 * SUCH DAMAGE. 43 * 44 * The licence and distribution terms for any publically available version or 45 * derivative of this code cannot be changed. i.e. this code cannot simply be 46 * copied and put under another distribution licence 47 * [including the GNU Public Licence.] 48 */ 49 50 /* set_key.c v 1.4 eay 24/9/91 51 * 1.4 Speed up by 400% :-) 52 * 1.3 added register declarations. 53 * 1.2 unrolled make_key_sched a bit more 54 * 1.1 added norm_expand_bits 55 * 1.0 First working version 56 */ 57 #include "des_locl.h" 58 #include "podd.h" 59 #include "sk.h" 60 61 #ifdef PROTO 62 static int check_parity(des_cblock (*key)); 63 #else 64 static int check_parity(); 65 #endif 66 67 int des_check_key=0; 68 69 void des_set_odd_parity(key) 70 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 78 static int check_parity(key) 79 des_cblock (*key); 80 { 81 int i; 82 83 for (i=0; i<DES_KEY_SZ; i++) 84 { 85 if ((*key)[i] != odd_parity[(*key)[i]]) 86 return(0); 87 } 88 return(1); 89 } 90 91 /* Weak and semi week keys as take from 92 * %A D.W. Davies 93 * %A W.L. Price 94 * %T Security for Computer Networks 95 * %I John Wiley & Sons 96 * %D 1984 97 * Many thanks to smb@ulysses.att.com (Steven Bellovin) for the reference 98 * (and actual cblock values). 99 */ 100 #define NUM_WEAK_KEY 16 101 static des_cblock weak_keys[NUM_WEAK_KEY]={ 102 /* weak keys */ 103 {0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01}, 104 {0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE}, 105 {0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F}, 106 {0xE0,0xE0,0xE0,0xE0,0xE0,0xE0,0xE0,0xE0}, 107 /* semi-weak keys */ 108 {0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE}, 109 {0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01}, 110 {0x1F,0xE0,0x1F,0xE0,0x0E,0xF1,0x0E,0xF1}, 111 {0xE0,0x1F,0xE0,0x1F,0xF1,0x0E,0xF1,0x0E}, 112 {0x01,0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1}, 113 {0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1,0x01}, 114 {0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E,0xFE}, 115 {0xFE,0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E}, 116 {0x01,0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E}, 117 {0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E,0x01}, 118 {0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1,0xFE}, 119 {0xFE,0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1}}; 120 121 int des_is_weak_key(key) 122 des_cblock (*key); 123 { 124 int i; 125 126 for (i=0; i<NUM_WEAK_KEY; i++) 127 /* Added == 0 to comparision, I obviously don't run 128 * this section very often :-(, thanks to 129 * engineering@MorningStar.Com for the fix 130 * eay 93/06/29 */ 131 if (bcmp(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 static int shifts2[16]={0,0,1,1,1,1,1,1,0,1,1,1,1,1,1,0}; 146 147 /* return 0 if key parity is odd (correct), 148 * return -1 if key parity error, 149 * return -2 if illegal weak key. 150 */ 151 int des_set_key(key, schedule) 152 des_cblock (*key); 153 des_key_schedule schedule; 154 { 155 register u_int32_t c,d,t,s; 156 register unsigned char *in; 157 register u_int32_t *k; 158 register int i; 159 160 if (des_check_key) 161 { 162 if (!check_parity(key)) 163 return(-1); 164 165 if (des_is_weak_key(key)) 166 return(-2); 167 } 168 169 k=(u_int32_t *)schedule; 170 in=(unsigned char *)key; 171 172 c2l(in,c); 173 c2l(in,d); 174 175 /* do PC1 in 60 simple operations */ 176 /* PERM_OP(d,c,t,4,0x0f0f0f0fL); 177 HPERM_OP(c,t,-2, 0xcccc0000L); 178 HPERM_OP(c,t,-1, 0xaaaa0000L); 179 HPERM_OP(c,t, 8, 0x00ff0000L); 180 HPERM_OP(c,t,-1, 0xaaaa0000L); 181 HPERM_OP(d,t,-8, 0xff000000L); 182 HPERM_OP(d,t, 8, 0x00ff0000L); 183 HPERM_OP(d,t, 2, 0x33330000L); 184 d=((d&0x00aa00aaL)<<7L)|((d&0x55005500L)>>7L)|(d&0xaa55aa55L); 185 d=(d>>8)|((c&0xf0000000L)>>4); 186 c&=0x0fffffffL; */ 187 188 /* I now do it in 47 simple operations :-) 189 * Thanks to John Fletcher (john_fletcher@lccmail.ocf.llnl.gov) 190 * for the inspiration. :-) */ 191 PERM_OP (d,c,t,4,0x0f0f0f0fL); 192 HPERM_OP(c,t,-2,0xcccc0000L); 193 HPERM_OP(d,t,-2,0xcccc0000L); 194 PERM_OP (d,c,t,1,0x55555555L); 195 PERM_OP (c,d,t,8,0x00ff00ffL); 196 PERM_OP (d,c,t,1,0x55555555L); 197 d= (((d&0x000000ffL)<<16L)| (d&0x0000ff00L) | 198 ((d&0x00ff0000L)>>16L)|((c&0xf0000000L)>>4L)); 199 c&=0x0fffffffL; 200 201 for (i=0; i<ITERATIONS; i++) 202 { 203 if (shifts2[i]) 204 { c=((c>>2L)|(c<<26L)); d=((d>>2L)|(d<<26L)); } 205 else 206 { c=((c>>1L)|(c<<27L)); d=((d>>1L)|(d<<27L)); } 207 c&=0x0fffffffL; 208 d&=0x0fffffffL; 209 /* could be a few less shifts but I am to lazy at this 210 * point in time to investigate */ 211 s= des_skb[0][ (c )&0x3f ]| 212 des_skb[1][((c>> 6)&0x03)|((c>> 7L)&0x3c)]| 213 des_skb[2][((c>>13)&0x0f)|((c>>14L)&0x30)]| 214 des_skb[3][((c>>20)&0x01)|((c>>21L)&0x06) | 215 ((c>>22L)&0x38)]; 216 t= des_skb[4][ (d )&0x3f ]| 217 des_skb[5][((d>> 7L)&0x03)|((d>> 8L)&0x3c)]| 218 des_skb[6][ (d>>15L)&0x3f ]| 219 des_skb[7][((d>>21L)&0x0f)|((d>>22L)&0x30)]; 220 221 /* table contained 0213 4657 */ 222 *(k++)=((t<<16L)|(s&0x0000ffffL))&0xffffffffL; 223 s= ((s>>16L)|(t&0xffff0000L)); 224 225 s=(s<<4L)|(s>>28L); 226 *(k++)=s&0xffffffffL; 227 } 228 return(0); 229 } 230 231 int des_key_sched(key, schedule) 232 des_cblock (*key); 233 des_key_schedule schedule; 234 { 235 return(des_set_key(key,schedule)); 236 } 237