crypto/external/bsd/heimdal/dist/lib/hcrypto/libtommath/etc/2kprime.c

   1 /*      $NetBSD: 2kprime.c,v 1.1.1.2 2014/04/24 12:45:39 pettai Exp $   */
   2
   3 /* Makes safe primes of a 2k nature */
   4 #include <tommath.h>
   5 #include <time.h>
   6
   7 int sizes[] = {256, 512, 768, 1024, 1536, 2048, 3072, 4096};
   8
   9 int main(void)
  10 {
  11    char buf[2000];
  12    int x, y;
  13    mp_int q, p;
  14    FILE *out;
  15    clock_t t1;
  16    mp_digit z;
  17
  18    mp_init_multi(&q, &p, NULL);
  19
  20    out = fopen("2kprime.1", "w");
  21    for (x = 0; x < (int)(sizeof(sizes) / sizeof(sizes[0])); x++) {
  22    top:
  23        mp_2expt(&q, sizes[x]);
  24        mp_add_d(&q, 3, &q);
  25        z = -3;
  26
  27        t1 = clock();
  28        for(;;) {
  29          mp_sub_d(&q, 4, &q);
  30          z += 4;
  31
  32          if (z > MP_MASK) {
  33             printf("No primes of size %d found\n", sizes[x]);
  34             break;
  35          }
  36
  37          if (clock() - t1 > CLOCKS_PER_SEC) {
  38             printf("."); fflush(stdout);
  39 //            sleep((clock() - t1 + CLOCKS_PER_SEC/2)/CLOCKS_PER_SEC);
  40             t1 = clock();
  41          }
  42
  43          /* quick test on q */
  44          mp_prime_is_prime(&q, 1, &y);
  45          if (y == 0) {
  46             continue;
  47          }
  48
  49          /* find (q-1)/2 */
  50          mp_sub_d(&q, 1, &p);
  51          mp_div_2(&p, &p);
  52          mp_prime_is_prime(&p, 3, &y);
  53          if (y == 0) {
  54             continue;
  55          }
  56
  57          /* test on q */
  58          mp_prime_is_prime(&q, 3, &y);
  59          if (y == 0) {
  60             continue;
  61          }
  62
  63          break;
  64        }
  65
  66        if (y == 0) {
  67           ++sizes[x];
  68           goto top;
  69        }
  70
  71        mp_toradix(&q, buf, 10);
  72        printf("\n\n%d-bits (k = %lu) = %s\n", sizes[x], z, buf);
  73        fprintf(out, "%d-bits (k = %lu) = %s\n", sizes[x], z, buf); fflush(out);
  74    }
  75
  76    return 0;
  77 }
  78
  79
  80
  81
  82
  83
  84 /* Source: /cvs/libtom/libtommath/etc/2kprime.c,v  */
  85 /* Revision: 1.2  */
  86 /* Date: 2005/05/05 14:38:47  */