1/* $OpenBSD: set_key.c,v 1.5 2021/03/12 10:22:46 jsg 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 61static int check_parity(des_cblock (*key)); 62 63int des_check_key=0; 64 65static int 66check_parity(des_cblock (*key)) 67{ 68 int i; 69 70 for (i = 0; i < DES_KEY_SZ; i++) { 71 if ((*key)[i] != odd_parity[(*key)[i]]) 72 return(0); 73 } 74 return (1); 75} 76 77/* Weak and semi week keys as take from 78 * %A D.W. Davies 79 * %A W.L. Price 80 * %T Security for Computer Networks 81 * %I John Wiley & Sons 82 * %D 1984 83 * Many thanks to smb@ulysses.att.com (Steven Bellovin) for the reference 84 * (and actual cblock values). 85 */ 86#define NUM_WEAK_KEY 16 87static des_cblock weak_keys[NUM_WEAK_KEY]={ 88 /* weak keys */ 89 {0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01}, 90 {0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE}, 91 {0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F}, 92 {0xE0,0xE0,0xE0,0xE0,0xE0,0xE0,0xE0,0xE0}, 93 /* semi-weak keys */ 94 {0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE}, 95 {0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01}, 96 {0x1F,0xE0,0x1F,0xE0,0x0E,0xF1,0x0E,0xF1}, 97 {0xE0,0x1F,0xE0,0x1F,0xF1,0x0E,0xF1,0x0E}, 98 {0x01,0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1}, 99 {0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1,0x01}, 100 {0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E,0xFE}, 101 {0xFE,0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E}, 102 {0x01,0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E}, 103 {0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E,0x01}, 104 {0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1,0xFE}, 105 {0xFE,0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1}}; 106 107int 108des_is_weak_key(des_cblock (*key)) 109{ 110 int i; 111 112 for (i = 0; i < NUM_WEAK_KEY; i++) { 113 /* Added == 0 to comparison, I obviously don't run 114 * this section very often :-(, thanks to 115 * engineering@MorningStar.Com for the fix 116 * eay 93/06/29 */ 117 if (bcmp(weak_keys[i], key, sizeof(des_cblock)) == 0) 118 return (1); 119 } 120 return (0); 121} 122 123/* NOW DEFINED IN des_local.h 124 * See ecb_encrypt.c for a pseudo description of these macros. 125 * #define PERM_OP(a, b, t, n, m) ((t) = ((((a) >> (n))^(b)) & (m)),\ 126 * (b)^=(t),\ 127 * (a) = ((a)^((t) << (n)))) 128 */ 129 130#define HPERM_OP(a, t, n, m) ((t) = ((((a) << (16 - (n)))^(a)) & (m)),\ 131 (a) = (a)^(t)^(t >> (16 - (n)))) 132 133static int shifts2[16]={0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0}; 134 135/* return 0 if key parity is odd (correct), 136 * return -1 if key parity error, 137 * return -2 if illegal weak key. 138 */ 139int 140des_set_key(des_cblock (*key), des_key_schedule schedule) 141{ 142 register u_int32_t c, d, t, s; 143 register unsigned char *in; 144 register u_int32_t *k; 145 register int i; 146 147 if (des_check_key) { 148 if (!check_parity(key)) 149 return(-1); 150 151 if (des_is_weak_key(key)) 152 return(-2); 153 } 154 155 k = (u_int32_t *) schedule; 156 in = (unsigned char *) key; 157 158 c2l(in, c); 159 c2l(in, d); 160 161 /* do PC1 in 60 simple operations */ 162/* PERM_OP(d, c, t, 4, 0x0f0f0f0fL); 163 HPERM_OP(c, t, -2, 0xcccc0000L); 164 HPERM_OP(c, t, -1, 0xaaaa0000L); 165 HPERM_OP(c, t, 8, 0x00ff0000L); 166 HPERM_OP(c, t, -1, 0xaaaa0000L); 167 HPERM_OP(d, t, -8, 0xff000000L); 168 HPERM_OP(d, t, 8, 0x00ff0000L); 169 HPERM_OP(d, t, 2, 0x33330000L); 170 d = ((d & 0x00aa00aaL) << 7L) | ((d & 0x55005500L) >> 7L) | (d & 0xaa55aa55L); 171 d = (d >> 8) | ((c & 0xf0000000L) >> 4); 172 c &= 0x0fffffffL; */ 173 174 /* I now do it in 47 simple operations :-) 175 * Thanks to John Fletcher (john_fletcher@lccmail.ocf.llnl.gov) 176 * for the inspiration. :-) */ 177 PERM_OP (d, c, t, 4, 0x0f0f0f0fL); 178 HPERM_OP(c, t, -2, 0xcccc0000L); 179 HPERM_OP(d, t, -2, 0xcccc0000L); 180 PERM_OP (d, c, t, 1, 0x55555555L); 181 PERM_OP (c, d, t, 8, 0x00ff00ffL); 182 PERM_OP (d, c, t, 1, 0x55555555L); 183 d = (((d & 0x000000ffL) << 16L) | (d & 0x0000ff00L) | 184 ((d & 0x00ff0000L) >> 16L) | ((c & 0xf0000000L) >> 4L)); 185 c &= 0x0fffffffL; 186 187 for (i = 0; i < ITERATIONS; i++) { 188 if (shifts2[i]) 189 { c = ((c >> 2L) | (c << 26L)); d = ((d >> 2L) | (d << 26L)); } 190 else 191 { c = ((c >> 1L) | (c << 27L)); d = ((d >> 1L) | (d << 27L)); } 192 c &= 0x0fffffffL; 193 d &= 0x0fffffffL; 194 /* could be a few less shifts but I am to lazy at this 195 * point in time to investigate */ 196 s = des_skb[0][ (c ) & 0x3f ]| 197 des_skb[1][((c >> 6) & 0x03) | ((c >> 7L) & 0x3c)]| 198 des_skb[2][((c >> 13) & 0x0f) | ((c >> 14L) & 0x30)]| 199 des_skb[3][((c >> 20) & 0x01) | ((c >> 21L) & 0x06) | 200 ((c >> 22L) & 0x38)]; 201 t = des_skb[4][ (d ) & 0x3f ]| 202 des_skb[5][((d >> 7L) & 0x03) | ((d >> 8L) & 0x3c)]| 203 des_skb[6][ (d >> 15L) & 0x3f ]| 204 des_skb[7][((d >> 21L) & 0x0f) | ((d >> 22L) & 0x30)]; 205 206 /* table contained 0213 4657 */ 207 *(k++) = ((t << 16L) | (s & 0x0000ffffL)) & 0xffffffffL; 208 s = ((s >> 16L) | (t & 0xffff0000L)); 209 210 s = (s << 4L) | (s >> 28L); 211 *(k++) = s & 0xffffffffL; 212 } 213 return (0); 214} 215