dropbear/libtommath/bn_mp_prime_is_divisible.c
Matt Johnston 9d5ed350a7 propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 2af95f00ebd5bb7a28b3817db1218442c935388e)
to branch 'au.asn.ucc.matt.dropbear' (head ecd779509ef23a8cdf64888904fc9b31d78aa933)

--HG--
extra : convert_revision : d26d5eb2837f46b56a33fb0e7573aa0201abd4d5
2007-01-11 03:14:55 +00:00

51 lines
1.3 KiB
C

#include <tommath.h>
#ifdef BN_MP_PRIME_IS_DIVISIBLE_C
/* 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@gmail.com, http://math.libtomcrypt.com
*/
/* determines if an integers is divisible by one
* of the first PRIME_SIZE primes or not
*
* sets result to 0 if not, 1 if yes
*/
int mp_prime_is_divisible (mp_int * a, int *result)
{
int err, ix;
mp_digit res;
/* default to not */
*result = MP_NO;
for (ix = 0; ix < PRIME_SIZE; ix++) {
/* what is a mod LBL_prime_tab[ix] */
if ((err = mp_mod_d (a, ltm_prime_tab[ix], &res)) != MP_OKAY) {
return err;
}
/* is the residue zero? */
if (res == 0) {
*result = MP_YES;
return MP_OKAY;
}
}
return MP_OKAY;
}
#endif
/* $Source: /cvs/libtom/libtommath/bn_mp_prime_is_divisible.c,v $ */
/* $Revision: 1.3 $ */
/* $Date: 2006/03/31 14:18:44 $ */