i_skey.c revision 296465
1/* crypto/idea/i_skey.c */ 2/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 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@cryptsoft.com). 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@cryptsoft.com)" 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@cryptsoft.com)" 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#include <openssl/idea.h> 60#include <openssl/crypto.h> 61#ifdef OPENSSL_FIPS 62# include <openssl/fips.h> 63#endif 64 65#include "idea_lcl.h" 66 67static IDEA_INT inverse(unsigned int xin); 68 69#ifdef OPENSSL_FIPS 70void idea_set_encrypt_key(const unsigned char *key, IDEA_KEY_SCHEDULE *ks) 71{ 72 if (FIPS_mode()) 73 FIPS_BAD_ABORT(IDEA) 74 private_idea_set_encrypt_key(key, ks); 75} 76 77void private_idea_set_encrypt_key(const unsigned char *key, 78 IDEA_KEY_SCHEDULE *ks) 79#else 80void idea_set_encrypt_key(const unsigned char *key, IDEA_KEY_SCHEDULE *ks) 81#endif 82{ 83 int i; 84 register IDEA_INT *kt, *kf, r0, r1, r2; 85 86 kt = &(ks->data[0][0]); 87 n2s(key, kt[0]); 88 n2s(key, kt[1]); 89 n2s(key, kt[2]); 90 n2s(key, kt[3]); 91 n2s(key, kt[4]); 92 n2s(key, kt[5]); 93 n2s(key, kt[6]); 94 n2s(key, kt[7]); 95 96 kf = kt; 97 kt += 8; 98 for (i = 0; i < 6; i++) { 99 r2 = kf[1]; 100 r1 = kf[2]; 101 *(kt++) = ((r2 << 9) | (r1 >> 7)) & 0xffff; 102 r0 = kf[3]; 103 *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff; 104 r1 = kf[4]; 105 *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff; 106 r0 = kf[5]; 107 *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff; 108 r1 = kf[6]; 109 *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff; 110 r0 = kf[7]; 111 *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff; 112 r1 = kf[0]; 113 if (i >= 5) 114 break; 115 *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff; 116 *(kt++) = ((r1 << 9) | (r2 >> 7)) & 0xffff; 117 kf += 8; 118 } 119} 120 121void idea_set_decrypt_key(const IDEA_KEY_SCHEDULE *ek, IDEA_KEY_SCHEDULE *dk) 122{ 123 int r; 124 register IDEA_INT *tp, t; 125 const IDEA_INT *fp; 126 127 tp = &(dk->data[0][0]); 128 fp = &(ek->data[8][0]); 129 for (r = 0; r < 9; r++) { 130 *(tp++) = inverse(fp[0]); 131 *(tp++) = ((int)(0x10000L - fp[2]) & 0xffff); 132 *(tp++) = ((int)(0x10000L - fp[1]) & 0xffff); 133 *(tp++) = inverse(fp[3]); 134 if (r == 8) 135 break; 136 fp -= 6; 137 *(tp++) = fp[4]; 138 *(tp++) = fp[5]; 139 } 140 141 tp = &(dk->data[0][0]); 142 t = tp[1]; 143 tp[1] = tp[2]; 144 tp[2] = t; 145 146 t = tp[49]; 147 tp[49] = tp[50]; 148 tp[50] = t; 149} 150 151/* taken directly from the 'paper' I'll have a look at it later */ 152static IDEA_INT inverse(unsigned int xin) 153{ 154 long n1, n2, q, r, b1, b2, t; 155 156 if (xin == 0) 157 b2 = 0; 158 else { 159 n1 = 0x10001; 160 n2 = xin; 161 b2 = 1; 162 b1 = 0; 163 164 do { 165 r = (n1 % n2); 166 q = (n1 - r) / n2; 167 if (r == 0) { 168 if (b2 < 0) 169 b2 = 0x10001 + b2; 170 } else { 171 n1 = n2; 172 n2 = r; 173 t = b2; 174 b2 = b1 - q * b2; 175 b1 = t; 176 } 177 } while (r != 0); 178 } 179 return ((IDEA_INT) b2); 180} 181