crypto/rc2/rc2_cbc.c

   1 /* crypto/rc2/rc2_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/rc2.h>
  60 #include "rc2_locl.h"
  61
  62 void RC2_cbc_encrypt(const unsigned char *in, unsigned char *out, long length,
  63              RC2_KEY *ks, unsigned char *iv, int encrypt)
  64         {
  65         register unsigned long tin0,tin1;
  66         register unsigned long tout0,tout1,xor0,xor1;
  67         register long l=length;
  68         unsigned long tin[2];
  69
  70         if (encrypt)
  71                 {
  72                 c2l(iv,tout0);
  73                 c2l(iv,tout1);
  74                 iv-=8;
  75                 for (l-=8; l>=0; l-=8)
  76                         {
  77                         c2l(in,tin0);
  78                         c2l(in,tin1);
  79                         tin0^=tout0;
  80                         tin1^=tout1;
  81                         tin[0]=tin0;
  82                         tin[1]=tin1;
  83                         RC2_encrypt(tin,ks);
  84                         tout0=tin[0]; l2c(tout0,out);
  85                         tout1=tin[1]; l2c(tout1,out);
  86                         }
  87                 if (l != -8)
  88                         {
  89                         c2ln(in,tin0,tin1,l+8);
  90                         tin0^=tout0;
  91                         tin1^=tout1;
  92                         tin[0]=tin0;
  93                         tin[1]=tin1;
  94                         RC2_encrypt(tin,ks);
  95                         tout0=tin[0]; l2c(tout0,out);
  96                         tout1=tin[1]; l2c(tout1,out);
  97                         }
  98                 l2c(tout0,iv);
  99                 l2c(tout1,iv);
 100                 }
 101         else
 102                 {
 103                 c2l(iv,xor0);
 104                 c2l(iv,xor1);
 105                 iv-=8;
 106                 for (l-=8; l>=0; l-=8)
 107                         {
 108                         c2l(in,tin0); tin[0]=tin0;
 109                         c2l(in,tin1); tin[1]=tin1;
 110                         RC2_decrypt(tin,ks);
 111                         tout0=tin[0]^xor0;
 112                         tout1=tin[1]^xor1;
 113                         l2c(tout0,out);
 114                         l2c(tout1,out);
 115                         xor0=tin0;
 116                         xor1=tin1;
 117                         }
 118                 if (l != -8)
 119                         {
 120                         c2l(in,tin0); tin[0]=tin0;
 121                         c2l(in,tin1); tin[1]=tin1;
 122                         RC2_decrypt(tin,ks);
 123                         tout0=tin[0]^xor0;
 124                         tout1=tin[1]^xor1;
 125                         l2cn(tout0,tout1,out,l+8);
 126                         xor0=tin0;
 127                         xor1=tin1;
 128                         }
 129                 l2c(xor0,iv);
 130                 l2c(xor1,iv);
 131                 }
 132         tin0=tin1=tout0=tout1=xor0=xor1=0;
 133         tin[0]=tin[1]=0;
 134         }
 135
 136 void RC2_encrypt(unsigned long *d, RC2_KEY *key)
 137         {
 138         int i,n;
 139         register RC2_INT *p0,*p1;
 140         register RC2_INT x0,x1,x2,x3,t;
 141         unsigned long l;
 142
 143         l=d[0];
 144         x0=(RC2_INT)l&0xffff;
 145         x1=(RC2_INT)(l>>16L);
 146         l=d[1];
 147         x2=(RC2_INT)l&0xffff;
 148         x3=(RC2_INT)(l>>16L);
 149
 150         n=3;
 151         i=5;
 152
 153         p0=p1= &(key->data[0]);
 154         for (;;)
 155                 {
 156                 t=(x0+(x1& ~x3)+(x2&x3)+ *(p0++))&0xffff;
 157                 x0=(t<<1)|(t>>15);
 158                 t=(x1+(x2& ~x0)+(x3&x0)+ *(p0++))&0xffff;
 159                 x1=(t<<2)|(t>>14);
 160                 t=(x2+(x3& ~x1)+(x0&x1)+ *(p0++))&0xffff;
 161                 x2=(t<<3)|(t>>13);
 162                 t=(x3+(x0& ~x2)+(x1&x2)+ *(p0++))&0xffff;
 163                 x3=(t<<5)|(t>>11);
 164
 165                 if (--i == 0)
 166                         {
 167                         if (--n == 0) break;
 168                         i=(n == 2)?6:5;
 169
 170                         x0+=p1[x3&0x3f];
 171                         x1+=p1[x0&0x3f];
 172                         x2+=p1[x1&0x3f];
 173                         x3+=p1[x2&0x3f];
 174                         }
 175                 }
 176
 177         d[0]=(unsigned long)(x0&0xffff)|((unsigned long)(x1&0xffff)<<16L);
 178         d[1]=(unsigned long)(x2&0xffff)|((unsigned long)(x3&0xffff)<<16L);
 179         }
 180
 181 void RC2_decrypt(unsigned long *d, RC2_KEY *key)
 182         {
 183         int i,n;
 184         register RC2_INT *p0,*p1;
 185         register RC2_INT x0,x1,x2,x3,t;
 186         unsigned long l;
 187
 188         l=d[0];
 189         x0=(RC2_INT)l&0xffff;
 190         x1=(RC2_INT)(l>>16L);
 191         l=d[1];
 192         x2=(RC2_INT)l&0xffff;
 193         x3=(RC2_INT)(l>>16L);
 194
 195         n=3;
 196         i=5;
 197
 198         p0= &(key->data[63]);
 199         p1= &(key->data[0]);
 200         for (;;)
 201                 {
 202                 t=((x3<<11)|(x3>>5))&0xffff;
 203                 x3=(t-(x0& ~x2)-(x1&x2)- *(p0--))&0xffff;
 204                 t=((x2<<13)|(x2>>3))&0xffff;
 205                 x2=(t-(x3& ~x1)-(x0&x1)- *(p0--))&0xffff;
 206                 t=((x1<<14)|(x1>>2))&0xffff;
 207                 x1=(t-(x2& ~x0)-(x3&x0)- *(p0--))&0xffff;
 208                 t=((x0<<15)|(x0>>1))&0xffff;
 209                 x0=(t-(x1& ~x3)-(x2&x3)- *(p0--))&0xffff;
 210
 211                 if (--i == 0)
 212                         {
 213                         if (--n == 0) break;
 214                         i=(n == 2)?6:5;
 215
 216                         x3=(x3-p1[x2&0x3f])&0xffff;
 217                         x2=(x2-p1[x1&0x3f])&0xffff;
 218                         x1=(x1-p1[x0&0x3f])&0xffff;
 219                         x0=(x0-p1[x3&0x3f])&0xffff;
 220                         }
 221                 }
 222
 223         d[0]=(unsigned long)(x0&0xffff)|((unsigned long)(x1&0xffff)<<16L);
 224         d[1]=(unsigned long)(x2&0xffff)|((unsigned long)(x3&0xffff)<<16L);
 225         }
 226