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comparison libtommath/bn_mp_dr_is_modulus.c @ 1692:1051e4eea25a

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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
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1691:2d3745d58843 1692:1051e4eea25a
1 #include "tommath_private.h" 1 #include "tommath_private.h"
2 #ifdef BN_MP_DR_IS_MODULUS_C 2 #ifdef BN_MP_DR_IS_MODULUS_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 /* determines if a number is a valid DR modulus */ 6 /* determines if a number is a valid DR modulus */
16 int mp_dr_is_modulus(const mp_int *a) 7 mp_bool mp_dr_is_modulus(const mp_int *a)
17 { 8 {
18 int ix; 9 int ix;
19 10
20 /* must be at least two digits */ 11 /* must be at least two digits */
21 if (a->used < 2) { 12 if (a->used < 2) {
22 return 0; 13 return MP_NO;
23 } 14 }
24 15
25 /* must be of the form b**k - a [a <= b] so all 16 /* must be of the form b**k - a [a <= b] so all
26 * but the first digit must be equal to -1 (mod b). 17 * but the first digit must be equal to -1 (mod b).
27 */ 18 */
28 for (ix = 1; ix < a->used; ix++) { 19 for (ix = 1; ix < a->used; ix++) {
29 if (a->dp[ix] != MP_MASK) { 20 if (a->dp[ix] != MP_MASK) {
30 return 0; 21 return MP_NO;
31 } 22 }
32 } 23 }
33 return 1; 24 return MP_YES;
34 } 25 }
35 26
36 #endif 27 #endif
37
38 /* ref: HEAD -> master, tag: v1.1.0 */
39 /* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
40 /* commit time: 2019-01-28 20:32:32 +0100 */