comparison libtommath/bn_mp_mod.c @ 1692:1051e4eea25a

Update LibTomMath to 1.2.0 (#84) * update C files * update other files * update headers * update makefiles * remove mp_set/get_double() * use ltm 1.2.0 API * update ltm_desc * use bundled tommath if system-tommath is too old * XMALLOC etc. were changed to MP_MALLOC etc.
author Steffen Jaeckel <s@jaeckel.eu>
date Tue, 26 May 2020 17:36:47 +0200
parents f52919ffd3b1
children
comparison
equal deleted inserted replaced
1691:2d3745d58843 1692:1051e4eea25a
1 #include "tommath_private.h" 1 #include "tommath_private.h"
2 #ifdef BN_MP_MOD_C 2 #ifdef BN_MP_MOD_C
3 /* LibTomMath, multiple-precision integer library -- Tom St Denis 3 /* LibTomMath, multiple-precision integer library -- Tom St Denis */
4 * 4 /* SPDX-License-Identifier: Unlicense */
5 * LibTomMath is a library that provides multiple-precision
6 * integer arithmetic as well as number theoretic functionality.
7 *
8 * The library was designed directly after the MPI library by
9 * Michael Fromberger but has been written from scratch with
10 * additional optimizations in place.
11 *
12 * SPDX-License-Identifier: Unlicense
13 */
14 5
15 /* c = a mod b, 0 <= c < b if b > 0, b < c <= 0 if b < 0 */ 6 /* c = a mod b, 0 <= c < b if b > 0, b < c <= 0 if b < 0 */
16 int mp_mod(const mp_int *a, const mp_int *b, mp_int *c) 7 mp_err mp_mod(const mp_int *a, const mp_int *b, mp_int *c)
17 { 8 {
18 mp_int t; 9 mp_int t;
19 int res; 10 mp_err err;
20 11
21 if ((res = mp_init_size(&t, b->used)) != MP_OKAY) { 12 if ((err = mp_init_size(&t, b->used)) != MP_OKAY) {
22 return res; 13 return err;
23 } 14 }
24 15
25 if ((res = mp_div(a, b, NULL, &t)) != MP_OKAY) { 16 if ((err = mp_div(a, b, NULL, &t)) != MP_OKAY) {
26 mp_clear(&t); 17 goto LBL_ERR;
27 return res;
28 } 18 }
29 19
30 if ((mp_iszero(&t) != MP_NO) || (t.sign == b->sign)) { 20 if (MP_IS_ZERO(&t) || (t.sign == b->sign)) {
31 res = MP_OKAY; 21 err = MP_OKAY;
32 mp_exch(&t, c); 22 mp_exch(&t, c);
33 } else { 23 } else {
34 res = mp_add(b, &t, c); 24 err = mp_add(b, &t, c);
35 } 25 }
36 26
27 LBL_ERR:
37 mp_clear(&t); 28 mp_clear(&t);
38 return res; 29 return err;
39 } 30 }
40 #endif 31 #endif
41
42 /* ref: HEAD -> master, tag: v1.1.0 */
43 /* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
44 /* commit time: 2019-01-28 20:32:32 +0100 */