1 /* $NetBSD: bn_mp_mod.c,v 1.1.1.2 2014/04/24 12:45:31 pettai Exp $ */
2
3 #include <tommath.h>
4 #ifdef BN_MP_MOD_C
5 /* LibTomMath, multiple-precision integer library -- Tom St Denis
6 *
7 * LibTomMath is a library that provides multiple-precision
8 * integer arithmetic as well as number theoretic functionality.
9 *
10 * The library was designed directly after the MPI library by
11 * Michael Fromberger but has been written from scratch with
12 * additional optimizations in place.
13 *
14 * The library is free for all purposes without any express
15 * guarantee it works.
16 *
17 * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
18 */
19
20 /* c = a mod b, 0 <= c < b */
21 int
mp_mod(mp_int * a,mp_int * b,mp_int * c)22 mp_mod (mp_int * a, mp_int * b, mp_int * c)
23 {
24 mp_int t;
25 int res;
26
27 if ((res = mp_init (&t)) != MP_OKAY) {
28 return res;
29 }
30
31 if ((res = mp_div (a, b, NULL, &t)) != MP_OKAY) {
32 mp_clear (&t);
33 return res;
34 }
35
36 if (t.sign != b->sign) {
37 res = mp_add (b, &t, c);
38 } else {
39 res = MP_OKAY;
40 mp_exch (&t, c);
41 }
42
43 mp_clear (&t);
44 return res;
45 }
46 #endif
47
48 /* Source: /cvs/libtom/libtommath/bn_mp_mod.c,v */
49 /* Revision: 1.4 */
50 /* Date: 2006/12/28 01:25:13 */
51