1 /* crypto/cast/c_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 <openssl/cast.h>
  60 #include <cast_lcl.h>
  61 
  62 void CAST_encrypt(CAST_LONG *data, const CAST_KEY *key)
  63         {
  64         register CAST_LONG l,r,t;
  65         register const CAST_LONG *k;
  66 
  67         k= &(key->data[0]);
  68         l=data[0];
  69         r=data[1];
  70 
  71         E_CAST( 0,k,l,r,+,^,-);
  72         E_CAST( 1,k,r,l,^,-,+);
  73         E_CAST( 2,k,l,r,-,+,^);
  74         E_CAST( 3,k,r,l,+,^,-);
  75         E_CAST( 4,k,l,r,^,-,+);
  76         E_CAST( 5,k,r,l,-,+,^);
  77         E_CAST( 6,k,l,r,+,^,-);
  78         E_CAST( 7,k,r,l,^,-,+);
  79         E_CAST( 8,k,l,r,-,+,^);
  80         E_CAST( 9,k,r,l,+,^,-);
  81         E_CAST(10,k,l,r,^,-,+);
  82         E_CAST(11,k,r,l,-,+,^);
  83         if(!key->short_key)
  84             {
  85             E_CAST(12,k,l,r,+,^,-);
  86             E_CAST(13,k,r,l,^,-,+);
  87             E_CAST(14,k,l,r,-,+,^);
  88             E_CAST(15,k,r,l,+,^,-);
  89             }
  90 
  91         data[1]=l&0xffffffffL;
  92         data[0]=r&0xffffffffL;
  93         }
  94 
  95 void CAST_decrypt(CAST_LONG *data, const CAST_KEY *key)
  96         {
  97         register CAST_LONG l,r,t;
  98         register const CAST_LONG *k;
  99 
 100         k= &(key->data[0]);
 101         l=data[0];
 102         r=data[1];
 103 
 104         if(!key->short_key)
 105             {
 106             E_CAST(15,k,l,r,+,^,-);
 107             E_CAST(14,k,r,l,-,+,^);
 108             E_CAST(13,k,l,r,^,-,+);
 109             E_CAST(12,k,r,l,+,^,-);
 110             }
 111         E_CAST(11,k,l,r,-,+,^);
 112         E_CAST(10,k,r,l,^,-,+);
 113         E_CAST( 9,k,l,r,+,^,-);
 114         E_CAST( 8,k,r,l,-,+,^);
 115         E_CAST( 7,k,l,r,^,-,+);
 116         E_CAST( 6,k,r,l,+,^,-);
 117         E_CAST( 5,k,l,r,-,+,^);
 118         E_CAST( 4,k,r,l,^,-,+);
 119         E_CAST( 3,k,l,r,+,^,-);
 120         E_CAST( 2,k,r,l,-,+,^);
 121         E_CAST( 1,k,l,r,^,-,+);
 122         E_CAST( 0,k,r,l,+,^,-);
 123 
 124         data[1]=l&0xffffffffL;
 125         data[0]=r&0xffffffffL;
 126         }
 127 
 128 void CAST_cbc_encrypt(const unsigned char *in, unsigned char *out, long length,
 129              const CAST_KEY *ks, unsigned char *iv, int enc)
 130         {
 131         register CAST_LONG tin0,tin1;
 132         register CAST_LONG tout0,tout1,xor0,xor1;
 133         register long l=length;
 134         CAST_LONG tin[2];
 135 
 136         if (enc)
 137                 {
 138                 n2l(iv,tout0);
 139                 n2l(iv,tout1);
 140                 iv-=8;
 141                 for (l-=8; l>=0; l-=8)
 142                         {
 143                         n2l(in,tin0);
 144                         n2l(in,tin1);
 145                         tin0^=tout0;
 146                         tin1^=tout1;
 147                         tin[0]=tin0;
 148                         tin[1]=tin1;
 149                         CAST_encrypt(tin,ks);
 150                         tout0=tin[0];
 151                         tout1=tin[1];
 152                         l2n(tout0,out);
 153                         l2n(tout1,out);
 154                         }
 155                 if (l != -8)
 156                         {
 157                         n2ln(in,tin0,tin1,l+8);
 158                         tin0^=tout0;
 159                         tin1^=tout1;
 160                         tin[0]=tin0;
 161                         tin[1]=tin1;
 162                         CAST_encrypt(tin,ks);
 163                         tout0=tin[0];
 164                         tout1=tin[1];
 165                         l2n(tout0,out);
 166                         l2n(tout1,out);
 167                         }
 168                 l2n(tout0,iv);
 169                 l2n(tout1,iv);
 170                 }
 171         else
 172                 {
 173                 n2l(iv,xor0);
 174                 n2l(iv,xor1);
 175                 iv-=8;
 176                 for (l-=8; l>=0; l-=8)
 177                         {
 178                         n2l(in,tin0);
 179                         n2l(in,tin1);
 180                         tin[0]=tin0;
 181                         tin[1]=tin1;
 182                         CAST_decrypt(tin,ks);
 183                         tout0=tin[0]^xor0;
 184                         tout1=tin[1]^xor1;
 185                         l2n(tout0,out);
 186                         l2n(tout1,out);
 187                         xor0=tin0;
 188                         xor1=tin1;
 189                         }
 190                 if (l != -8)
 191                         {
 192                         n2l(in,tin0);
 193                         n2l(in,tin1);
 194                         tin[0]=tin0;
 195                         tin[1]=tin1;
 196                         CAST_decrypt(tin,ks);
 197                         tout0=tin[0]^xor0;
 198                         tout1=tin[1]^xor1;
 199                         l2nn(tout0,tout1,out,l+8);
 200                         xor0=tin0;
 201                         xor1=tin1;
 202                         }
 203                 l2n(xor0,iv);
 204                 l2n(xor1,iv);
 205                 }
 206         tin0=tin1=tout0=tout1=xor0=xor1=0;
 207         tin[0]=tin[1]=0;
 208         }