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