crypto/cast/c_skey.c

   1 /* crypto/cast/c_skey.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 "cast.h"
  60 #include "cast_lcl.h"
  61 #include "cast_s.h"
  62
  63 #define CAST_exp(l,A,a,n) \
  64         A[n/4]=l; \
  65         a[n+3]=(l    )&0xff; \
  66         a[n+2]=(l>> 8)&0xff; \
  67         a[n+1]=(l>>16)&0xff; \
  68         a[n+0]=(l>>24)&0xff;
  69
  70 #define S4 CAST_S_table4
  71 #define S5 CAST_S_table5
  72 #define S6 CAST_S_table6
  73 #define S7 CAST_S_table7
  74
  75 void CAST_set_key(key,len,data)
  76 CAST_KEY *key;
  77 int len;
  78 unsigned char *data;
  79         {
  80         CAST_LONG x[16];
  81         CAST_LONG z[16];
  82         CAST_LONG k[32];
  83         CAST_LONG X[4],Z[4];
  84         CAST_LONG l,*K;
  85         int i;
  86
  87         for (i=0; i<16; i++) x[i]=0;
  88         if (len > 16) len=16;
  89         for (i=0; i<len; i++)
  90                 x[i]=data[i];
  91
  92         K= &k[0];
  93         X[0]=((x[ 0]<<24)|(x[ 1]<<16)|(x[ 2]<<8)|x[ 3])&0xffffffffL;
  94         X[1]=((x[ 4]<<24)|(x[ 5]<<16)|(x[ 6]<<8)|x[ 7])&0xffffffffL;
  95         X[2]=((x[ 8]<<24)|(x[ 9]<<16)|(x[10]<<8)|x[11])&0xffffffffL;
  96         X[3]=((x[12]<<24)|(x[13]<<16)|(x[14]<<8)|x[15])&0xffffffffL;
  97
  98         for (;;)
  99                 {
 100         l=X[0]^S4[x[13]]^S5[x[15]]^S6[x[12]]^S7[x[14]]^S6[x[ 8]];
 101         CAST_exp(l,Z,z, 0);
 102         l=X[2]^S4[z[ 0]]^S5[z[ 2]]^S6[z[ 1]]^S7[z[ 3]]^S7[x[10]];
 103         CAST_exp(l,Z,z, 4);
 104         l=X[3]^S4[z[ 7]]^S5[z[ 6]]^S6[z[ 5]]^S7[z[ 4]]^S4[x[ 9]];
 105         CAST_exp(l,Z,z, 8);
 106         l=X[1]^S4[z[10]]^S5[z[ 9]]^S6[z[11]]^S7[z[ 8]]^S5[x[11]];
 107         CAST_exp(l,Z,z,12);
 108
 109         K[ 0]= S4[z[ 8]]^S5[z[ 9]]^S6[z[ 7]]^S7[z[ 6]]^S4[z[ 2]];
 110         K[ 1]= S4[z[10]]^S5[z[11]]^S6[z[ 5]]^S7[z[ 4]]^S5[z[ 6]];
 111         K[ 2]= S4[z[12]]^S5[z[13]]^S6[z[ 3]]^S7[z[ 2]]^S6[z[ 9]];
 112         K[ 3]= S4[z[14]]^S5[z[15]]^S6[z[ 1]]^S7[z[ 0]]^S7[z[12]];
 113
 114         l=Z[2]^S4[z[ 5]]^S5[z[ 7]]^S6[z[ 4]]^S7[z[ 6]]^S6[z[ 0]];
 115         CAST_exp(l,X,x, 0);
 116         l=Z[0]^S4[x[ 0]]^S5[x[ 2]]^S6[x[ 1]]^S7[x[ 3]]^S7[z[ 2]];
 117         CAST_exp(l,X,x, 4);
 118         l=Z[1]^S4[x[ 7]]^S5[x[ 6]]^S6[x[ 5]]^S7[x[ 4]]^S4[z[ 1]];
 119         CAST_exp(l,X,x, 8);
 120         l=Z[3]^S4[x[10]]^S5[x[ 9]]^S6[x[11]]^S7[x[ 8]]^S5[z[ 3]];
 121         CAST_exp(l,X,x,12);
 122
 123         K[ 4]= S4[x[ 3]]^S5[x[ 2]]^S6[x[12]]^S7[x[13]]^S4[x[ 8]];
 124         K[ 5]= S4[x[ 1]]^S5[x[ 0]]^S6[x[14]]^S7[x[15]]^S5[x[13]];
 125         K[ 6]= S4[x[ 7]]^S5[x[ 6]]^S6[x[ 8]]^S7[x[ 9]]^S6[x[ 3]];
 126         K[ 7]= S4[x[ 5]]^S5[x[ 4]]^S6[x[10]]^S7[x[11]]^S7[x[ 7]];
 127
 128         l=X[0]^S4[x[13]]^S5[x[15]]^S6[x[12]]^S7[x[14]]^S6[x[ 8]];
 129         CAST_exp(l,Z,z, 0);
 130         l=X[2]^S4[z[ 0]]^S5[z[ 2]]^S6[z[ 1]]^S7[z[ 3]]^S7[x[10]];
 131         CAST_exp(l,Z,z, 4);
 132         l=X[3]^S4[z[ 7]]^S5[z[ 6]]^S6[z[ 5]]^S7[z[ 4]]^S4[x[ 9]];
 133         CAST_exp(l,Z,z, 8);
 134         l=X[1]^S4[z[10]]^S5[z[ 9]]^S6[z[11]]^S7[z[ 8]]^S5[x[11]];
 135         CAST_exp(l,Z,z,12);
 136
 137         K[ 8]= S4[z[ 3]]^S5[z[ 2]]^S6[z[12]]^S7[z[13]]^S4[z[ 9]];
 138         K[ 9]= S4[z[ 1]]^S5[z[ 0]]^S6[z[14]]^S7[z[15]]^S5[z[12]];
 139         K[10]= S4[z[ 7]]^S5[z[ 6]]^S6[z[ 8]]^S7[z[ 9]]^S6[z[ 2]];
 140         K[11]= S4[z[ 5]]^S5[z[ 4]]^S6[z[10]]^S7[z[11]]^S7[z[ 6]];
 141
 142         l=Z[2]^S4[z[ 5]]^S5[z[ 7]]^S6[z[ 4]]^S7[z[ 6]]^S6[z[ 0]];
 143         CAST_exp(l,X,x, 0);
 144         l=Z[0]^S4[x[ 0]]^S5[x[ 2]]^S6[x[ 1]]^S7[x[ 3]]^S7[z[ 2]];
 145         CAST_exp(l,X,x, 4);
 146         l=Z[1]^S4[x[ 7]]^S5[x[ 6]]^S6[x[ 5]]^S7[x[ 4]]^S4[z[ 1]];
 147         CAST_exp(l,X,x, 8);
 148         l=Z[3]^S4[x[10]]^S5[x[ 9]]^S6[x[11]]^S7[x[ 8]]^S5[z[ 3]];
 149         CAST_exp(l,X,x,12);
 150
 151         K[12]= S4[x[ 8]]^S5[x[ 9]]^S6[x[ 7]]^S7[x[ 6]]^S4[x[ 3]];
 152         K[13]= S4[x[10]]^S5[x[11]]^S6[x[ 5]]^S7[x[ 4]]^S5[x[ 7]];
 153         K[14]= S4[x[12]]^S5[x[13]]^S6[x[ 3]]^S7[x[ 2]]^S6[x[ 8]];
 154         K[15]= S4[x[14]]^S5[x[15]]^S6[x[ 1]]^S7[x[ 0]]^S7[x[13]];
 155         if (K != k)  break;
 156         K+=16;
 157                 }
 158
 159         for (i=0; i<16; i++)
 160                 {
 161                 key->data[i*2]=k[i];
 162                 key->data[i*2+1]=((k[i+16])+16)&0x1f;
 163                 }
 164         }
 165