1 #include <tommath.h> 2 #ifdef BN_MP_PRIME_IS_DIVISIBLE_C 3 /* LibTomMath, multiple-precision integer library -- Tom St Denis 4 * 5 * LibTomMath is a library that provides multiple-precision 6 * integer arithmetic as well as number theoretic functionality. 7 * 8 * The library was designed directly after the MPI library by 9 * Michael Fromberger but has been written from scratch with 10 * additional optimizations in place. 11 * 12 * The library is free for all purposes without any express 13 * guarantee it works. 14 * 15 * Tom St Denis, tomstdenis (at) gmail.com, http://math.libtomcrypt.com 16 */ 17 18 /* determines if an integers is divisible by one 19 * of the first PRIME_SIZE primes or not 20 * 21 * sets result to 0 if not, 1 if yes 22 */ 23 int mp_prime_is_divisible (mp_int * a, int *result) 24 { 25 int err, ix; 26 mp_digit res; 27 28 /* default to not */ 29 *result = MP_NO; 30 31 for (ix = 0; ix < PRIME_SIZE; ix++) { 32 /* what is a mod LBL_prime_tab[ix] */ 33 if ((err = mp_mod_d (a, ltm_prime_tab[ix], &res)) != MP_OKAY) { 34 return err; 35 } 36 37 /* is the residue zero? */ 38 if (res == 0) { 39 *result = MP_YES; 40 return MP_OKAY; 41 } 42 } 43 44 return MP_OKAY; 45 } 46 #endif 47 48 /* $Source: /cvs/libtom/libtommath/bn_mp_prime_is_divisible.c,v $ */ 49 /* $Revision: 1.3 $ */ 50 /* $Date: 2006/03/31 14:18:44 $ */ 51
