/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
* LibTomMath is a library that provides multiple-precision
* integer arithmetic as well as number theoretic functionality.
*
* The library was designed directly after the MPI library by
* Michael Fromberger but has been written from scratch with
* additional optimizations in place.
*
* The library is free for all purposes without any express
* guarantee it works.
*
* Tom St Denis, tomstdenis@iahu.ca, http://math.libtomcrypt.org
*/
#include <tommath.h>
/* this table gives the # of rabin miller trials for a prob of failure lower than 2^-96 */
static const struct {
int k, t;
} sizes[] = {
{ 128, 28 },
{ 256, 16 },
{ 384, 10 },
{ 512, 7 },
{ 640, 6 },
{ 768, 5 },
{ 896, 4 },
{ 1024, 4 },
{ 1152, 3 },
{ 1280, 3 },
{ 1408, 3 },
{ 1536, 3 },
{ 1664, 3 },
{ 1792, 2 } };
/* returns # of RM trials required for a given bit size */
int mp_prime_rabin_miller_trials(int size)
{
int x;
for (x = 0; x < (int)(sizeof(sizes)/(sizeof(sizes[0]))); x++) {
if (sizes[x].k == size) {
return sizes[x].t;
} else if (sizes[x].k > size) {
return (x == 0) ? sizes[0].t : sizes[x - 1].t;
}
}
return 1;
}
