42 lines
978 B
C
42 lines
978 B
C
#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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*
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* LibTomMath is a library that provides multiple-precision
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* integer arithmetic as well as number theoretic functionality.
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*
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* The library was designed directly after the MPI library by
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* Michael Fromberger but has been written from scratch with
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* additional optimizations in place.
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*
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* The library is free for all purposes without any express
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* guarantee it works.
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*
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* Tom St Denis, tstdenis82@gmail.com, http://libtom.org
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*/
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/* d = a - b (mod c) */
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int mp_submod(mp_int *a, mp_int *b, mp_int *c, mp_int *d)
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{
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int res;
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mp_int t;
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if ((res = mp_init(&t)) != MP_OKAY) {
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return res;
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}
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if ((res = mp_sub(a, b, &t)) != MP_OKAY) {
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mp_clear(&t);
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return res;
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}
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res = mp_mod(&t, c, d);
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mp_clear(&t);
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return res;
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}
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#endif
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/* ref: $Format:%D$ */
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/* git commit: $Format:%H$ */
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/* commit time: $Format:%ai$ */
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