crypto/des/rand_key.c

   1 /* crypto/des/rand_key.c */
   2 /* Copyright (C) 1995-1997 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 "des_locl.h"
  60 #include <time.h>
  61
  62 static int seed=0;
  63 static des_cblock init;
  64
  65 void des_random_seed(key)
  66 des_cblock key;
  67         {
  68         memcpy(init,key,sizeof(des_cblock));
  69         seed=1;
  70         }
  71
  72 void des_random_key(ret)
  73 unsigned char *ret;
  74         {
  75         des_key_schedule ks;
  76         static DES_LONG c=0;
  77         static unsigned short pid=0;
  78         static des_cblock data={0x01,0x23,0x45,0x67,0x89,0xab,0xcd,0xef};
  79         des_cblock key;
  80         unsigned char *p;
  81         DES_LONG t;
  82         int i;
  83
  84 #ifdef MSDOS
  85         pid=1;
  86 #else
  87         if (!pid) pid=getpid();
  88 #endif
  89         p=key;
  90         if (seed)
  91                 {
  92                 for (i=0; i<8; i++)
  93                         {
  94                         data[i] ^= init[i];
  95                         init[i]=0;
  96                         }
  97                 seed=0;
  98                 }
  99         t=(DES_LONG)time(NULL);
 100         l2c(t,p);
 101         t=(DES_LONG)((pid)|((c++)<<16));
 102         l2c(t,p);
 103
 104         des_set_odd_parity((des_cblock *)data);
 105         des_set_key((des_cblock *)data,ks);
 106         des_cbc_cksum((des_cblock *)key,(des_cblock *)key,
 107                 (long)sizeof(key),ks,(des_cblock *)data);
 108
 109         des_set_odd_parity((des_cblock *)key);
 110         des_set_key((des_cblock *)key,ks);
 111         des_cbc_cksum((des_cblock *)key,(des_cblock *)data,
 112                 (long)sizeof(key),ks,(des_cblock *)key);
 113
 114         memcpy(ret,data,sizeof(key));
 115         memset(key,0,sizeof(key));
 116         memset(ks,0,sizeof(ks));
 117         t=0;
 118         }