1 /* $OpenBSD: i_skey.c,v 1.3 2014/06/12 15:49:29 deraadt Exp $ */ 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/crypto.h> 60 #include <openssl/idea.h> 61 #include "idea_lcl.h" 62 63 static IDEA_INT inverse(unsigned int xin); 64 void idea_set_encrypt_key(const unsigned char *key, IDEA_KEY_SCHEDULE *ks) 65 { 66 int i; 67 IDEA_INT *kt,*kf,r0,r1,r2; 68 69 kt= &(ks->data[0][0]); 70 n2s(key,kt[0]); n2s(key,kt[1]); n2s(key,kt[2]); n2s(key,kt[3]); 71 n2s(key,kt[4]); n2s(key,kt[5]); n2s(key,kt[6]); n2s(key,kt[7]); 72 73 kf=kt; 74 kt+=8; 75 for (i=0; i<6; i++) 76 { 77 r2= kf[1]; 78 r1= kf[2]; 79 *(kt++)= ((r2<<9) | (r1>>7))&0xffff; 80 r0= kf[3]; 81 *(kt++)= ((r1<<9) | (r0>>7))&0xffff; 82 r1= kf[4]; 83 *(kt++)= ((r0<<9) | (r1>>7))&0xffff; 84 r0= kf[5]; 85 *(kt++)= ((r1<<9) | (r0>>7))&0xffff; 86 r1= kf[6]; 87 *(kt++)= ((r0<<9) | (r1>>7))&0xffff; 88 r0= kf[7]; 89 *(kt++)= ((r1<<9) | (r0>>7))&0xffff; 90 r1= kf[0]; 91 if (i >= 5) break; 92 *(kt++)= ((r0<<9) | (r1>>7))&0xffff; 93 *(kt++)= ((r1<<9) | (r2>>7))&0xffff; 94 kf+=8; 95 } 96 } 97 98 void idea_set_decrypt_key(IDEA_KEY_SCHEDULE *ek, IDEA_KEY_SCHEDULE *dk) 99 { 100 int r; 101 IDEA_INT *fp,*tp,t; 102 103 tp= &(dk->data[0][0]); 104 fp= &(ek->data[8][0]); 105 for (r=0; r<9; r++) 106 { 107 *(tp++)=inverse(fp[0]); 108 *(tp++)=((int)(0x10000L-fp[2])&0xffff); 109 *(tp++)=((int)(0x10000L-fp[1])&0xffff); 110 *(tp++)=inverse(fp[3]); 111 if (r == 8) break; 112 fp-=6; 113 *(tp++)=fp[4]; 114 *(tp++)=fp[5]; 115 } 116 117 tp= &(dk->data[0][0]); 118 t=tp[1]; 119 tp[1]=tp[2]; 120 tp[2]=t; 121 122 t=tp[49]; 123 tp[49]=tp[50]; 124 tp[50]=t; 125 } 126 127 /* taken directly from the 'paper' I'll have a look at it later */ 128 static IDEA_INT inverse(unsigned int xin) 129 { 130 long n1,n2,q,r,b1,b2,t; 131 132 if (xin == 0) 133 b2=0; 134 else 135 { 136 n1=0x10001; 137 n2=xin; 138 b2=1; 139 b1=0; 140 141 do { 142 r=(n1%n2); 143 q=(n1-r)/n2; 144 if (r == 0) 145 { if (b2 < 0) b2=0x10001+b2; } 146 else 147 { 148 n1=n2; 149 n2=r; 150 t=b2; 151 b2=b1-q*b2; 152 b1=t; 153 } 154 } while (r != 0); 155 } 156 return((IDEA_INT)b2); 157 } 158