crypto/external/bsd/openssl/lib/libcrypto/rnd_keys.c

   1 /*      $NetBSD: rnd_keys.c,v 1.2 2014/03/27 16:26:22 apb Exp $ */
   2
   3 #include "des_locl.h"
   4 #include <sys/time.h>
   5 #include <sys/types.h>
   6
   7 #include <fcntl.h>
   8 #include <unistd.h>
   9
  10 #include <sha1.h>
  11
  12 void
  13 des_set_random_generator_seed(des_cblock *seed)
  14 {
  15
  16         des_random_seed(seed);
  17 }
  18
  19 /*
  20  * Generate a sequence of random des keys
  21  * using the random block sequence, fixup
  22  * parity and skip weak keys.
  23  */
  24 int
  25 des_new_random_key(des_cblock *key)
  26 {
  27         int urandom;
  28
  29  again:
  30         urandom = open("/dev/urandom", O_RDONLY);
  31
  32         if (urandom < 0)
  33                 des_random_key(key);
  34         else {
  35                 if (read(urandom, key,
  36                     sizeof(des_cblock)) != sizeof(des_cblock)) {
  37                         close(urandom);
  38                         des_random_key(key);
  39                 } else
  40                         close(urandom);
  41         }
  42
  43         /* random key must have odd parity and not be weak */
  44         des_set_odd_parity(key);
  45         if (des_is_weak_key(key))
  46                 goto again;
  47
  48         return (0);
  49 }
  50
  51 /*
  52  * des_init_random_number_generator:
  53  *
  54  * This routine takes a secret key possibly shared by a number of servers
  55  * and uses it to generate a random number stream that is not shared by
  56  * any of the other servers.  It does this by using the current process id,
  57  * host id, and the current time to the nearest second.  The resulting
  58  * stream seed is not useful information for cracking the secret key.
  59  * Moreover, this routine keeps no copy of the secret key.
  60  */
  61 void
  62 des_init_random_number_generator(des_cblock *seed)
  63 {
  64         u_int64_t seed_q;
  65         des_cblock seed_new;
  66         SHA1_CTX sha;
  67
  68         u_char results[20];
  69         char hname[64], accum[512];
  70
  71         struct timeval when;
  72
  73         SHA1Init(&sha);
  74
  75         gethostname(hname, sizeof(hname) - 1);
  76         gettimeofday(&when, NULL);
  77
  78         memcpy(&seed_q, seed, sizeof(seed_q));
  79
  80         snprintf(accum, sizeof(accum), "%ld%ld%d%s%d%lld",
  81             when.tv_sec, when.tv_usec, getpid(), hname, getuid(),
  82             (long long) seed_q);
  83
  84         SHA1Update(&sha, (u_char *) accum, strlen(accum));
  85
  86         memset(accum, 0, sizeof(accum));
  87
  88         SHA1Final(results, &sha);
  89
  90         memcpy(seed_new, results, sizeof(seed_new));
  91         des_random_seed(&seed_new);
  92
  93         memset(seed_new, 0, sizeof(seed_new));
  94         memset(results, 0, sizeof(results));
  95 }