26 lines
510 B
C
26 lines
510 B
C
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#include "tommath_private.h"
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#ifdef BN_MP_SUBMOD_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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/* d = a - b (mod c) */
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mp_err mp_submod(const mp_int *a, const mp_int *b, const mp_int *c, mp_int *d)
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{
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mp_err err;
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mp_int t;
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if ((err = mp_init(&t)) != MP_OKAY) {
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return err;
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}
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if ((err = mp_sub(a, b, &t)) != MP_OKAY) {
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goto LBL_ERR;
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}
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err = mp_mod(&t, c, d);
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LBL_ERR:
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mp_clear(&t);
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return err;
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}
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#endif
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