Mercurial > dropbear

annotate libtommath/bn_mp_mulmod.c @ 1060:4c733310c21d nocircbuffer

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reword comment for clarity
author Matt Johnston <matt@ucc.asn.au>
date Sun, 01 Mar 2015 23:26:42 +0800
parents 4fbf9a7556ed
children 60fc6476e044
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1 #include <tommath.h>
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2 #ifdef BN_MP_MULMOD_C
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3 /* LibTomMath, multiple-precision integer library -- Tom St Denis
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4 *
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5 * LibTomMath is a library that provides multiple-precision
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6 * integer arithmetic as well as number theoretic functionality.
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7 *
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8 * The library was designed directly after the MPI library by
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9 * Michael Fromberger but has been written from scratch with
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10 * additional optimizations in place.
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11 *
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12 * The library is free for all purposes without any express
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13 * guarantee it works.
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14 *
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15 * Tom St Denis, [email protected], http://math.libtomcrypt.com
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16 */
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18 /* d = a * b (mod c) */
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19 int mp_mulmod (mp_int * a, mp_int * b, mp_int * c, mp_int * d)
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20 {
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21 int res;
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22 mp_int t;
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23
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4fbf9a7556ed Use mp_init_size() to avoid some mp_grow()s
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24 if ((res = mp_init_size (&t, c->used)) != MP_OKAY) {
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25 return res;
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26 }
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28 if ((res = mp_mul (a, b, &t)) != MP_OKAY) {
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29 mp_clear (&t);
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30 return res;
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31 }
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32 res = mp_mod (&t, c, d);
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33 mp_clear (&t);
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34 return res;
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35 }
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36 #endif
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38 /* $Source: /cvs/libtom/libtommath/bn_mp_mulmod.c,v $ */
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39 /* $Revision: 1.4 $ */
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40 /* $Date: 2006/03/31 14:18:44 $ */