bcec605af5
* it is an implementation detail used for prime testing * there is upcoming work by @czurnieden regarding a generalised prime sieve * furthermore remove jacobi test (replaced by kronecker)
36 lines
823 B
C
36 lines
823 B
C
#include "tommath_private.h"
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#ifdef BN_S_MP_PRIME_IS_DIVISIBLE_C
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/* LibTomMath, multiple-precision integer library -- Tom St Denis */
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/* SPDX-License-Identifier: Unlicense */
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/* determines if an integers is divisible by one
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* of the first PRIME_SIZE primes or not
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*
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* sets result to 0 if not, 1 if yes
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*/
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mp_err s_mp_prime_is_divisible(const mp_int *a, mp_bool *result)
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{
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int ix;
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mp_err err;
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mp_digit res;
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/* default to not */
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*result = MP_NO;
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for (ix = 0; ix < PRIVATE_MP_PRIME_TAB_SIZE; ix++) {
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/* what is a mod LBL_prime_tab[ix] */
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if ((err = mp_mod_d(a, s_mp_prime_tab[ix], &res)) != MP_OKAY) {
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return err;
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}
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/* is the residue zero? */
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if (res == 0u) {
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*result = MP_YES;
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return MP_OKAY;
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}
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}
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return MP_OKAY;
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}
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#endif
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