crypto/des/xcbc_enc.c

   1 /* crypto/des/xcbc_enc.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 "des_locl.h"
  60
  61 /* RSA's DESX */
  62
  63 void DES_xcbc_encrypt(const unsigned char *in, unsigned char *out,
  64                       long length, DES_key_schedule *schedule,
  65                       DES_cblock *ivec, const_DES_cblock *inw,
  66                       const_DES_cblock *outw, int enc)
  67 {
  68     register DES_LONG tin0, tin1;
  69     register DES_LONG tout0, tout1, xor0, xor1;
  70     register DES_LONG inW0, inW1, outW0, outW1;
  71     register const unsigned char *in2;
  72     register long l = length;
  73     DES_LONG tin[2];
  74     unsigned char *iv;
  75
  76     in2 = &(*inw)[0];
  77     c2l(in2, inW0);
  78     c2l(in2, inW1);
  79     in2 = &(*outw)[0];
  80     c2l(in2, outW0);
  81     c2l(in2, outW1);
  82
  83     iv = &(*ivec)[0];
  84
  85     if (enc) {
  86         c2l(iv, tout0);
  87         c2l(iv, tout1);
  88         for (l -= 8; l >= 0; l -= 8) {
  89             c2l(in, tin0);
  90             c2l(in, tin1);
  91             tin0 ^= tout0 ^ inW0;
  92             tin[0] = tin0;
  93             tin1 ^= tout1 ^ inW1;
  94             tin[1] = tin1;
  95             DES_encrypt1(tin, schedule, DES_ENCRYPT);
  96             tout0 = tin[0] ^ outW0;
  97             l2c(tout0, out);
  98             tout1 = tin[1] ^ outW1;
  99             l2c(tout1, out);
 100         }
 101         if (l != -8) {
 102             c2ln(in, tin0, tin1, l + 8);
 103             tin0 ^= tout0 ^ inW0;
 104             tin[0] = tin0;
 105             tin1 ^= tout1 ^ inW1;
 106             tin[1] = tin1;
 107             DES_encrypt1(tin, schedule, DES_ENCRYPT);
 108             tout0 = tin[0] ^ outW0;
 109             l2c(tout0, out);
 110             tout1 = tin[1] ^ outW1;
 111             l2c(tout1, out);
 112         }
 113         iv = &(*ivec)[0];
 114         l2c(tout0, iv);
 115         l2c(tout1, iv);
 116     } else {
 117         c2l(iv, xor0);
 118         c2l(iv, xor1);
 119         for (l -= 8; l > 0; l -= 8) {
 120             c2l(in, tin0);
 121             tin[0] = tin0 ^ outW0;
 122             c2l(in, tin1);
 123             tin[1] = tin1 ^ outW1;
 124             DES_encrypt1(tin, schedule, DES_DECRYPT);
 125             tout0 = tin[0] ^ xor0 ^ inW0;
 126             tout1 = tin[1] ^ xor1 ^ inW1;
 127             l2c(tout0, out);
 128             l2c(tout1, out);
 129             xor0 = tin0;
 130             xor1 = tin1;
 131         }
 132         if (l != -8) {
 133             c2l(in, tin0);
 134             tin[0] = tin0 ^ outW0;
 135             c2l(in, tin1);
 136             tin[1] = tin1 ^ outW1;
 137             DES_encrypt1(tin, schedule, DES_DECRYPT);
 138             tout0 = tin[0] ^ xor0 ^ inW0;
 139             tout1 = tin[1] ^ xor1 ^ inW1;
 140             l2cn(tout0, tout1, out, l + 8);
 141             xor0 = tin0;
 142             xor1 = tin1;
 143         }
 144
 145         iv = &(*ivec)[0];
 146         l2c(xor0, iv);
 147         l2c(xor1, iv);
 148     }
 149     tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;
 150     inW0 = inW1 = outW0 = outW1 = 0;
 151     tin[0] = tin[1] = 0;
 152 }