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comparison libtommath/bn_mp_reduce_2k_setup.c @ 1655:f52919ffd3b1

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update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79) * make key-generation compliant to FIPS 186.4 * fix includes in tommath_class.h * update fuzzcorpus instead of error-out * fixup fuzzing make-targets * update Makefile.in * apply necessary patches to ltm sources * clean-up not required ltm files * update to vanilla ltm 1.1.0 this already only contains the required files * remove set/get double
author Steffen Jaeckel <s_jaeckel@gmx.de>
date Mon, 16 Sep 2019 15:50:38 +0200
parents 8bba51a55704
children 1051e4eea25a
comparison
equal deleted inserted replaced
1654:cc0fc5131c5c 1655:f52919ffd3b1
1 #include <tommath_private.h> 1 #include "tommath_private.h"
2 #ifdef BN_MP_REDUCE_2K_SETUP_C 2 #ifdef BN_MP_REDUCE_2K_SETUP_C
3 /* LibTomMath, multiple-precision integer library -- Tom St Denis 3 /* LibTomMath, multiple-precision integer library -- Tom St Denis
4 * 4 *
5 * LibTomMath is a library that provides multiple-precision 5 * LibTomMath is a library that provides multiple-precision
6 * integer arithmetic as well as number theoretic functionality. 6 * integer arithmetic as well as number theoretic functionality.
7 * 7 *
8 * The library was designed directly after the MPI library by 8 * The library was designed directly after the MPI library by
9 * Michael Fromberger but has been written from scratch with 9 * Michael Fromberger but has been written from scratch with
10 * additional optimizations in place. 10 * additional optimizations in place.
11 * 11 *
12 * The library is free for all purposes without any express 12 * SPDX-License-Identifier: Unlicense
13 * guarantee it works.
14 *
15 * Tom St Denis, [email protected], http://libtom.org
16 */ 13 */
17 14
18 /* determines the setup value */ 15 /* determines the setup value */
19 int mp_reduce_2k_setup(mp_int *a, mp_digit *d) 16 int mp_reduce_2k_setup(const mp_int *a, mp_digit *d)
20 { 17 {
21 int res, p; 18 int res, p;
22 mp_int tmp; 19 mp_int tmp;
23 20
24 if ((res = mp_init(&tmp)) != MP_OKAY) { 21 if ((res = mp_init(&tmp)) != MP_OKAY) {
25 return res; 22 return res;
26 } 23 }
27 24
28 p = mp_count_bits(a); 25 p = mp_count_bits(a);
29 if ((res = mp_2expt(&tmp, p)) != MP_OKAY) { 26 if ((res = mp_2expt(&tmp, p)) != MP_OKAY) {
30 mp_clear(&tmp); 27 mp_clear(&tmp);
31 return res; 28 return res;
32 } 29 }
33 30
34 if ((res = s_mp_sub(&tmp, a, &tmp)) != MP_OKAY) { 31 if ((res = s_mp_sub(&tmp, a, &tmp)) != MP_OKAY) {
35 mp_clear(&tmp); 32 mp_clear(&tmp);
36 return res; 33 return res;
37 } 34 }
38 35
39 *d = tmp.dp[0]; 36 *d = tmp.dp[0];
40 mp_clear(&tmp); 37 mp_clear(&tmp);
41 return MP_OKAY; 38 return MP_OKAY;
42 } 39 }
43 #endif 40 #endif
44 41
45 /* ref: $Format:%D$ */ 42 /* ref: HEAD -> master, tag: v1.1.0 */
46 /* git commit: $Format:%H$ */ 43 /* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
47 /* commit time: $Format:%ai$ */ 44 /* commit time: 2019-01-28 20:32:32 +0100 */