master-server/deps/libtommath/etc/mont.c
2024-05-15 15:20:32 -04:00

49 lines
1.6 KiB
C

/* tests the montgomery routines */
#include <tommath.h>
#include <stdlib.h>
#include <time.h>
int main(void)
{
mp_int modulus, R, p, pp;
mp_digit mp;
mp_err err;
int x, y;
srand(time(NULL));
if ((err = mp_init_multi(&modulus, &R, &p, &pp, NULL)) != MP_OKAY) goto LTM_ERR;
/* loop through various sizes */
for (x = 4; x < 256; x++) {
printf("DIGITS == %3d...", x);
fflush(stdout);
/* make up the odd modulus */
if ((err = mp_rand(&modulus, x)) != MP_OKAY) goto LTM_ERR;
modulus.dp[0] |= 1uL;
/* now find the R value */
if ((err = mp_montgomery_calc_normalization(&R, &modulus)) != MP_OKAY) goto LTM_ERR;
if ((err = mp_montgomery_setup(&modulus, &mp)) != MP_OKAY) goto LTM_ERR;
/* now run through a bunch tests */
for (y = 0; y < 1000; y++) {
/* p = random */
if ((err = mp_rand(&p, x/2)) != MP_OKAY) goto LTM_ERR;
/* pp = R * p */
if ((err = mp_mul(&p, &R, &pp)) != MP_OKAY) goto LTM_ERR;
if ((err = mp_montgomery_reduce(&pp, &modulus, mp)) != MP_OKAY) goto LTM_ERR;
/* should be equal to p */
if (mp_cmp(&pp, &p) != MP_EQ) {
printf("FAILURE!\n");
exit(-1);
}
}
printf("PASSED\n");
}
LTM_ERR:
return 0;
}