crypto/des/ncbc_enc.c

   1 /*
   2  * Copyright 1998-2016 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 /*-
  11  * #included by:
  12  *    cbc_enc.c  (DES_cbc_encrypt)
  13  *    des_enc.c  (DES_ncbc_encrypt)
  14  */
  15
  16 #include "des_locl.h"
  17
  18 #ifdef CBC_ENC_C__DONT_UPDATE_IV
  19 void DES_cbc_encrypt(const unsigned char *in, unsigned char *out, long length,
  20                      DES_key_schedule *_schedule, DES_cblock *ivec, int enc)
  21 #else
  22 void DES_ncbc_encrypt(const unsigned char *in, unsigned char *out,
  23                       long length, DES_key_schedule *_schedule,
  24                       DES_cblock *ivec, int enc)
  25 #endif
  26 {
  27     register DES_LONG tin0, tin1;
  28     register DES_LONG tout0, tout1, xor0, xor1;
  29     register long l = length;
  30     DES_LONG tin[2];
  31     unsigned char *iv;
  32
  33     iv = &(*ivec)[0];
  34
  35     if (enc) {
  36         c2l(iv, tout0);
  37         c2l(iv, tout1);
  38         for (l -= 8; l >= 0; l -= 8) {
  39             c2l(in, tin0);
  40             c2l(in, tin1);
  41             tin0 ^= tout0;
  42             tin[0] = tin0;
  43             tin1 ^= tout1;
  44             tin[1] = tin1;
  45             DES_encrypt1((DES_LONG *)tin, _schedule, DES_ENCRYPT);
  46             tout0 = tin[0];
  47             l2c(tout0, out);
  48             tout1 = tin[1];
  49             l2c(tout1, out);
  50         }
  51         if (l != -8) {
  52             c2ln(in, tin0, tin1, l + 8);
  53             tin0 ^= tout0;
  54             tin[0] = tin0;
  55             tin1 ^= tout1;
  56             tin[1] = tin1;
  57             DES_encrypt1((DES_LONG *)tin, _schedule, DES_ENCRYPT);
  58             tout0 = tin[0];
  59             l2c(tout0, out);
  60             tout1 = tin[1];
  61             l2c(tout1, out);
  62         }
  63 #ifndef CBC_ENC_C__DONT_UPDATE_IV
  64         iv = &(*ivec)[0];
  65         l2c(tout0, iv);
  66         l2c(tout1, iv);
  67 #endif
  68     } else {
  69         c2l(iv, xor0);
  70         c2l(iv, xor1);
  71         for (l -= 8; l >= 0; l -= 8) {
  72             c2l(in, tin0);
  73             tin[0] = tin0;
  74             c2l(in, tin1);
  75             tin[1] = tin1;
  76             DES_encrypt1((DES_LONG *)tin, _schedule, DES_DECRYPT);
  77             tout0 = tin[0] ^ xor0;
  78             tout1 = tin[1] ^ xor1;
  79             l2c(tout0, out);
  80             l2c(tout1, out);
  81             xor0 = tin0;
  82             xor1 = tin1;
  83         }
  84         if (l != -8) {
  85             c2l(in, tin0);
  86             tin[0] = tin0;
  87             c2l(in, tin1);
  88             tin[1] = tin1;
  89             DES_encrypt1((DES_LONG *)tin, _schedule, DES_DECRYPT);
  90             tout0 = tin[0] ^ xor0;
  91             tout1 = tin[1] ^ xor1;
  92             l2cn(tout0, tout1, out, l + 8);
  93 #ifndef CBC_ENC_C__DONT_UPDATE_IV
  94             xor0 = tin0;
  95             xor1 = tin1;
  96 #endif
  97         }
  98 #ifndef CBC_ENC_C__DONT_UPDATE_IV
  99         iv = &(*ivec)[0];
 100         l2c(xor0, iv);
 101         l2c(xor1, iv);
 102 #endif
 103     }
 104     tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;
 105     tin[0] = tin[1] = 0;
 106 }