1 /* crypto/des/set_key.c */ 2 /* Copyright (C) 1995-1997 Eric Young (eay@mincom.oz.au) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@mincom.oz.au). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@mincom.oz.au). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@mincom.oz.au)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@mincom.oz.au)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 59 /* set_key.c v 1.4 eay 24/9/91 60 * 1.4 Speed up by 400% :-) 61 * 1.3 added register declarations. 62 * 1.2 unrolled make_key_sched a bit more 63 * 1.1 added norm_expand_bits 64 * 1.0 First working version 65 */ 66 #include "des_locl.h" 67 #include "podd.h" 68 #include "sk.h" 69 70 #ifndef NOPROTO 71 static int check_parity(des_cblock (*key)); 72 #else 73 static int check_parity(); 74 #endif 75 76 int des_check_key=0; 77 78 void des_set_odd_parity(key) 79 des_cblock (*key); 80 { 81 int i; 82 83 for (i=0; i<DES_KEY_SZ; i++) 84 (*key)[i]=odd_parity[(*key)[i]]; 85 } 86 87 static int check_parity(key) 88 des_cblock (*key); 89 { 90 int i; 91 92 for (i=0; i<DES_KEY_SZ; i++) 93 { 94 if ((*key)[i] != odd_parity[(*key)[i]]) 95 return(0); 96 } 97 return(1); 98 } 99 100 /* Weak and semi week keys as take from 101 * %A D.W. Davies 102 * %A W.L. Price 103 * %T Security for Computer Networks 104 * %I John Wiley & Sons 105 * %D 1984 106 * Many thanks to smb@ulysses.att.com (Steven Bellovin) for the reference 107 * (and actual cblock values). 108 */ 109 #define NUM_WEAK_KEY 16 110 static des_cblock weak_keys[NUM_WEAK_KEY]={ 111 /* weak keys */ 112 {0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01}, 113 {0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE}, 114 {0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F}, 115 {0xE0,0xE0,0xE0,0xE0,0xE0,0xE0,0xE0,0xE0}, 116 /* semi-weak keys */ 117 {0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE}, 118 {0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01}, 119 {0x1F,0xE0,0x1F,0xE0,0x0E,0xF1,0x0E,0xF1}, 120 {0xE0,0x1F,0xE0,0x1F,0xF1,0x0E,0xF1,0x0E}, 121 {0x01,0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1}, 122 {0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1,0x01}, 123 {0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E,0xFE}, 124 {0xFE,0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E}, 125 {0x01,0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E}, 126 {0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E,0x01}, 127 {0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1,0xFE}, 128 {0xFE,0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1}}; 129 130 int des_is_weak_key(key) 131 des_cblock (*key); 132 { 133 int i; 134 135 for (i=0; i<NUM_WEAK_KEY; i++) 136 /* Added == 0 to comparision, I obviously don't run 137 * this section very often :-(, thanks to 138 * engineering@MorningStar.Com for the fix 139 * eay 93/06/29 */ 140 if (memcmp(weak_keys[i],key,sizeof(key)) == 0) return(1); 141 return(0); 142 } 143 144 /* NOW DEFINED IN des_local.h 145 * See ecb_encrypt.c for a pseudo description of these macros. 146 * #define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\ 147 * (b)^=(t),\ 148 * (a)=((a)^((t)<<(n)))) 149 */ 150 151 #define HPERM_OP(a,t,n,m) ((t)=((((a)<<(16-(n)))^(a))&(m)),\ 152 (a)=(a)^(t)^(t>>(16-(n)))) 153 154 /* return 0 if key parity is odd (correct), 155 * return -1 if key parity error, 156 * return -2 if illegal weak key. 157 */ 158 int des_set_key(key, schedule) 159 des_cblock (*key); 160 des_key_schedule schedule; 161 { 162 static int shifts2[16]={0,0,1,1,1,1,1,1,0,1,1,1,1,1,1,0}; 163 register DES_LONG c,d,t,s,t2; 164 register unsigned char *in; 165 register DES_LONG *k; 166 register int i; 167 168 if (des_check_key) 169 { 170 if (!check_parity(key)) 171 return(-1); 172 173 if (des_is_weak_key(key)) 174 return(-2); 175 } 176 177 k=(DES_LONG *)schedule; 178 in=(unsigned char *)key; 179 180 c2l(in,c); 181 c2l(in,d); 182 183 /* do PC1 in 60 simple operations */ 184 /* PERM_OP(d,c,t,4,0x0f0f0f0fL); 185 HPERM_OP(c,t,-2, 0xcccc0000L); 186 HPERM_OP(c,t,-1, 0xaaaa0000L); 187 HPERM_OP(c,t, 8, 0x00ff0000L); 188 HPERM_OP(c,t,-1, 0xaaaa0000L); 189 HPERM_OP(d,t,-8, 0xff000000L); 190 HPERM_OP(d,t, 8, 0x00ff0000L); 191 HPERM_OP(d,t, 2, 0x33330000L); 192 d=((d&0x00aa00aaL)<<7L)|((d&0x55005500L)>>7L)|(d&0xaa55aa55L); 193 d=(d>>8)|((c&0xf0000000L)>>4); 194 c&=0x0fffffffL; */ 195 196 /* I now do it in 47 simple operations :-) 197 * Thanks to John Fletcher (john_fletcher@lccmail.ocf.llnl.gov) 198 * for the inspiration. :-) */ 199 PERM_OP (d,c,t,4,0x0f0f0f0fL); 200 HPERM_OP(c,t,-2,0xcccc0000L); 201 HPERM_OP(d,t,-2,0xcccc0000L); 202 PERM_OP (d,c,t,1,0x55555555L); 203 PERM_OP (c,d,t,8,0x00ff00ffL); 204 PERM_OP (d,c,t,1,0x55555555L); 205 d= (((d&0x000000ffL)<<16L)| (d&0x0000ff00L) | 206 ((d&0x00ff0000L)>>16L)|((c&0xf0000000L)>>4L)); 207 c&=0x0fffffffL; 208 209 for (i=0; i<ITERATIONS; i++) 210 { 211 if (shifts2[i]) 212 { c=((c>>2L)|(c<<26L)); d=((d>>2L)|(d<<26L)); } 213 else 214 { c=((c>>1L)|(c<<27L)); d=((d>>1L)|(d<<27L)); } 215 c&=0x0fffffffL; 216 d&=0x0fffffffL; 217 /* could be a few less shifts but I am to lazy at this 218 * point in time to investigate */ 219 s= des_skb[0][ (c )&0x3f ]| 220 des_skb[1][((c>> 6)&0x03)|((c>> 7L)&0x3c)]| 221 des_skb[2][((c>>13)&0x0f)|((c>>14L)&0x30)]| 222 des_skb[3][((c>>20)&0x01)|((c>>21L)&0x06) | 223 ((c>>22L)&0x38)]; 224 t= des_skb[4][ (d )&0x3f ]| 225 des_skb[5][((d>> 7L)&0x03)|((d>> 8L)&0x3c)]| 226 des_skb[6][ (d>>15L)&0x3f ]| 227 des_skb[7][((d>>21L)&0x0f)|((d>>22L)&0x30)]; 228 229 /* table contained 0213 4657 */ 230 t2=((t<<16L)|(s&0x0000ffffL))&0xffffffffL; 231 *(k++)=ROTATE(t2,30)&0xffffffffL; 232 233 t2=((s>>16L)|(t&0xffff0000L)); 234 *(k++)=ROTATE(t2,26)&0xffffffffL; 235 } 236 return(0); 237 } 238 239 int des_key_sched(key, schedule) 240 des_cblock (*key); 241 des_key_schedule schedule; 242 { 243 return(des_set_key(key,schedule)); 244 } 245