release/src/router/openssl/crypto/idea/i_skey.c

   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/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 #ifdef OPENSSL_FIPS
  66 {
  67     fips_cipher_abort(IDEA);
  68     private_idea_set_encrypt_key(key, ks);
  69 }
  70
  71 void private_idea_set_encrypt_key(const unsigned char *key,
  72                                   IDEA_KEY_SCHEDULE *ks)
  73 #endif
  74 {
  75     int i;
  76     register IDEA_INT *kt, *kf, r0, r1, r2;
  77
  78     kt = &(ks->data[0][0]);
  79     n2s(key, kt[0]);
  80     n2s(key, kt[1]);
  81     n2s(key, kt[2]);
  82     n2s(key, kt[3]);
  83     n2s(key, kt[4]);
  84     n2s(key, kt[5]);
  85     n2s(key, kt[6]);
  86     n2s(key, kt[7]);
  87
  88     kf = kt;
  89     kt += 8;
  90     for (i = 0; i < 6; i++) {
  91         r2 = kf[1];
  92         r1 = kf[2];
  93         *(kt++) = ((r2 << 9) | (r1 >> 7)) & 0xffff;
  94         r0 = kf[3];
  95         *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff;
  96         r1 = kf[4];
  97         *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff;
  98         r0 = kf[5];
  99         *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff;
 100         r1 = kf[6];
 101         *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff;
 102         r0 = kf[7];
 103         *(kt++) = ((r1 << 9) | (r0 >> 7)) & 0xffff;
 104         r1 = kf[0];
 105         if (i >= 5)
 106             break;
 107         *(kt++) = ((r0 << 9) | (r1 >> 7)) & 0xffff;
 108         *(kt++) = ((r1 << 9) | (r2 >> 7)) & 0xffff;
 109         kf += 8;
 110     }
 111 }
 112
 113 void idea_set_decrypt_key(IDEA_KEY_SCHEDULE *ek, IDEA_KEY_SCHEDULE *dk)
 114 {
 115     int r;
 116     register IDEA_INT *fp, *tp, t;
 117
 118     tp = &(dk->data[0][0]);
 119     fp = &(ek->data[8][0]);
 120     for (r = 0; r < 9; r++) {
 121         *(tp++) = inverse(fp[0]);
 122         *(tp++) = ((int)(0x10000L - fp[2]) & 0xffff);
 123         *(tp++) = ((int)(0x10000L - fp[1]) & 0xffff);
 124         *(tp++) = inverse(fp[3]);
 125         if (r == 8)
 126             break;
 127         fp -= 6;
 128         *(tp++) = fp[4];
 129         *(tp++) = fp[5];
 130     }
 131
 132     tp = &(dk->data[0][0]);
 133     t = tp[1];
 134     tp[1] = tp[2];
 135     tp[2] = t;
 136
 137     t = tp[49];
 138     tp[49] = tp[50];
 139     tp[50] = t;
 140 }
 141
 142 /* taken directly from the 'paper' I'll have a look at it later */
 143 static IDEA_INT inverse(unsigned int xin)
 144 {
 145     long n1, n2, q, r, b1, b2, t;
 146
 147     if (xin == 0)
 148         b2 = 0;
 149     else {
 150         n1 = 0x10001;
 151         n2 = xin;
 152         b2 = 1;
 153         b1 = 0;
 154
 155         do {
 156             r = (n1 % n2);
 157             q = (n1 - r) / n2;
 158             if (r == 0) {
 159                 if (b2 < 0)
 160                     b2 = 0x10001 + b2;
 161             } else {
 162                 n1 = n2;
 163                 n2 = r;
 164                 t = b2;
 165                 b2 = b1 - q * b2;
 166                 b1 = t;
 167             }
 168         } while (r != 0);
 169     }
 170     return ((IDEA_INT) b2);
 171 }