crypto/bf/bf_cbc.c

   1 /* crypto/bf/bf_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 "blowfish.h"
  60 #include "bf_locl.h"
  61
  62 void BF_cbc_encrypt(unsigned char *in, unsigned char *out, long length,
  63              BF_KEY *ks, unsigned char *iv, int encrypt)
  64         {
  65         register BF_LONG tin0,tin1;
  66         register BF_LONG tout0,tout1,xor0,xor1;
  67         register long l=length;
  68         BF_LONG tin[2];
  69
  70         if (encrypt)
  71                 {
  72                 n2l(iv,tout0);
  73                 n2l(iv,tout1);
  74                 iv-=8;
  75                 for (l-=8; l>=0; l-=8)
  76                         {
  77                         n2l(in,tin0);
  78                         n2l(in,tin1);
  79                         tin0^=tout0;
  80                         tin1^=tout1;
  81                         tin[0]=tin0;
  82                         tin[1]=tin1;
  83                         BF_encrypt(tin,ks);
  84                         tout0=tin[0];
  85                         tout1=tin[1];
  86                         l2n(tout0,out);
  87                         l2n(tout1,out);
  88                         }
  89                 if (l != -8)
  90                         {
  91                         n2ln(in,tin0,tin1,l+8);
  92                         tin0^=tout0;
  93                         tin1^=tout1;
  94                         tin[0]=tin0;
  95                         tin[1]=tin1;
  96                         BF_encrypt(tin,ks);
  97                         tout0=tin[0];
  98                         tout1=tin[1];
  99                         l2n(tout0,out);
 100                         l2n(tout1,out);
 101                         }
 102                 l2n(tout0,iv);
 103                 l2n(tout1,iv);
 104                 }
 105         else
 106                 {
 107                 n2l(iv,xor0);
 108                 n2l(iv,xor1);
 109                 iv-=8;
 110                 for (l-=8; l>=0; l-=8)
 111                         {
 112                         n2l(in,tin0);
 113                         n2l(in,tin1);
 114                         tin[0]=tin0;
 115                         tin[1]=tin1;
 116                         BF_decrypt(tin,ks);
 117                         tout0=tin[0]^xor0;
 118                         tout1=tin[1]^xor1;
 119                         l2n(tout0,out);
 120                         l2n(tout1,out);
 121                         xor0=tin0;
 122                         xor1=tin1;
 123                         }
 124                 if (l != -8)
 125                         {
 126                         n2l(in,tin0);
 127                         n2l(in,tin1);
 128                         tin[0]=tin0;
 129                         tin[1]=tin1;
 130                         BF_decrypt(tin,ks);
 131                         tout0=tin[0]^xor0;
 132                         tout1=tin[1]^xor1;
 133                         l2nn(tout0,tout1,out,l+8);
 134                         xor0=tin0;
 135                         xor1=tin1;
 136                         }
 137                 l2n(xor0,iv);
 138                 l2n(xor1,iv);
 139                 }
 140         tin0=tin1=tout0=tout1=xor0=xor1=0;
 141         tin[0]=tin[1]=0;
 142         }
 143