libtommath/etc/2kprime.c
Daniel Mendler bf9507a9d4
replace mp_bool by stdbool
* This gives the advantage that static analysis **understands** bool,
  but complains about using an enum type instead of bool.

* If stdbool.h is not desired, true/false/bool can be replaced using sed
  as in the no-stdint-h branch.

* We already include stdint.h and stdbool.h is not more harmful than
  this header
2019-10-27 18:36:56 +01:00

82 lines
1.8 KiB
C

/* Makes safe primes of a 2k nature */
#include <tommath.h>
#include <time.h>
static int sizes[] = {256, 512, 768, 1024, 1536, 2048, 3072, 4096};
int main(void)
{
char buf[2000];
size_t x;
bool y;
mp_int q, p;
FILE *out;
clock_t t1;
mp_digit z;
mp_init_multi(&q, &p, NULL);
out = fopen("2kprime.1", "w");
if (out != NULL) {
for (x = 0; x < (sizeof(sizes) / sizeof(sizes[0])); x++) {
top:
mp_2expt(&q, sizes[x]);
mp_add_d(&q, 3uL, &q);
z = -3;
t1 = clock();
for (;;) {
mp_sub_d(&q, 4uL, &q);
z += 4uL;
if (z > MP_MASK) {
printf("No primes of size %d found\n", sizes[x]);
break;
}
if ((clock() - t1) > CLOCKS_PER_SEC) {
printf(".");
fflush(stdout);
/* sleep((clock() - t1 + CLOCKS_PER_SEC/2)/CLOCKS_PER_SEC); */
t1 = clock();
}
/* quick test on q */
mp_prime_is_prime(&q, 1, &y);
if (!y) {
continue;
}
/* find (q-1)/2 */
mp_sub_d(&q, 1uL, &p);
mp_div_2(&p, &p);
mp_prime_is_prime(&p, 3, &y);
if (!y) {
continue;
}
/* test on q */
mp_prime_is_prime(&q, 3, &y);
if (!y) {
continue;
}
break;
}
if (!y) {
++sizes[x];
goto top;
}
mp_to_decimal(&q, buf, sizeof(buf));
printf("\n\n%d-bits (k = %lu) = %s\n", sizes[x], z, buf);
fprintf(out, "%d-bits (k = %lu) = %s\n", sizes[x], z, buf);
fflush(out);
}
fclose(out);
}
return 0;
}