42 lines
1.0 KiB
C
42 lines
1.0 KiB
C
#include "tommath_private.h"
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#ifdef BN_MP_PRIME_RABIN_MILLER_TRIALS_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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static const struct {
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int k, t;
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} sizes[] = {
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{ 80, -1 }, /* Use deterministic algorithm for size <= 80 bits */
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{ 81, 39 },
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{ 96, 37 },
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{ 128, 32 },
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{ 160, 27 },
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{ 192, 21 },
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{ 256, 16 },
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{ 384, 10 },
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{ 512, 7 },
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{ 640, 6 },
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{ 768, 5 },
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{ 896, 4 },
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{ 1024, 4 },
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{ 2048, 2 } /* For bigger keysizes use always at least 2 Rounds */
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};
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/* returns # of RM trials required for a given bit size and max. error of 2^(-96)*/
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int mp_prime_rabin_miller_trials(int size)
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{
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int x;
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for (x = 0; x < (int)(sizeof(sizes)/(sizeof(sizes[0]))); x++) {
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if (sizes[x].k == size) {
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return sizes[x].t;
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} else if (sizes[x].k > size) {
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return (x == 0) ? sizes[0].t : sizes[x - 1].t;
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}
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}
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return sizes[x-1].t;
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}
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#endif
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