crypto/idea/i_cbc.c

   1 /* crypto/idea/i_cbc.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 "idea_lcl.h"
  61
  62 void idea_cbc_encrypt(const unsigned char *in, unsigned char *out,
  63                       long length, IDEA_KEY_SCHEDULE *ks, unsigned char *iv,
  64                       int encrypt)
  65 {
  66     register unsigned long tin0, tin1;
  67     register unsigned long tout0, tout1, xor0, xor1;
  68     register long l = length;
  69     unsigned long tin[2];
  70
  71     if (encrypt) {
  72         n2l(iv, tout0);
  73         n2l(iv, tout1);
  74         iv -= 8;
  75         for (l -= 8; l >= 0; l -= 8) {
  76             n2l(in, tin0);
  77             n2l(in, tin1);
  78             tin0 ^= tout0;
  79             tin1 ^= tout1;
  80             tin[0] = tin0;
  81             tin[1] = tin1;
  82             idea_encrypt(tin, ks);
  83             tout0 = tin[0];
  84             l2n(tout0, out);
  85             tout1 = tin[1];
  86             l2n(tout1, out);
  87         }
  88         if (l != -8) {
  89             n2ln(in, tin0, tin1, l + 8);
  90             tin0 ^= tout0;
  91             tin1 ^= tout1;
  92             tin[0] = tin0;
  93             tin[1] = tin1;
  94             idea_encrypt(tin, ks);
  95             tout0 = tin[0];
  96             l2n(tout0, out);
  97             tout1 = tin[1];
  98             l2n(tout1, out);
  99         }
 100         l2n(tout0, iv);
 101         l2n(tout1, iv);
 102     } else {
 103         n2l(iv, xor0);
 104         n2l(iv, xor1);
 105         iv -= 8;
 106         for (l -= 8; l >= 0; l -= 8) {
 107             n2l(in, tin0);
 108             tin[0] = tin0;
 109             n2l(in, tin1);
 110             tin[1] = tin1;
 111             idea_encrypt(tin, ks);
 112             tout0 = tin[0] ^ xor0;
 113             tout1 = tin[1] ^ xor1;
 114             l2n(tout0, out);
 115             l2n(tout1, out);
 116             xor0 = tin0;
 117             xor1 = tin1;
 118         }
 119         if (l != -8) {
 120             n2l(in, tin0);
 121             tin[0] = tin0;
 122             n2l(in, tin1);
 123             tin[1] = tin1;
 124             idea_encrypt(tin, ks);
 125             tout0 = tin[0] ^ xor0;
 126             tout1 = tin[1] ^ xor1;
 127             l2nn(tout0, tout1, out, l + 8);
 128             xor0 = tin0;
 129             xor1 = tin1;
 130         }
 131         l2n(xor0, iv);
 132         l2n(xor1, iv);
 133     }
 134     tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;
 135     tin[0] = tin[1] = 0;
 136 }
 137
 138 void idea_encrypt(unsigned long *d, IDEA_KEY_SCHEDULE *key)
 139 {
 140     register IDEA_INT *p;
 141     register unsigned long x1, x2, x3, x4, t0, t1, ul;
 142
 143     x2 = d[0];
 144     x1 = (x2 >> 16);
 145     x4 = d[1];
 146     x3 = (x4 >> 16);
 147
 148     p = &(key->data[0][0]);
 149
 150     E_IDEA(0);
 151     E_IDEA(1);
 152     E_IDEA(2);
 153     E_IDEA(3);
 154     E_IDEA(4);
 155     E_IDEA(5);
 156     E_IDEA(6);
 157     E_IDEA(7);
 158
 159     x1 &= 0xffff;
 160     idea_mul(x1, x1, *p, ul);
 161     p++;
 162
 163     t0 = x3 + *(p++);
 164     t1 = x2 + *(p++);
 165
 166     x4 &= 0xffff;
 167     idea_mul(x4, x4, *p, ul);
 168
 169     d[0] = (t0 & 0xffff) | ((x1 & 0xffff) << 16);
 170     d[1] = (x4 & 0xffff) | ((t1 & 0xffff) << 16);
 171 }