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comparison libtommath/bn_mp_invmod.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_INVMOD_C 2 #ifdef BN_MP_INVMOD_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 /* hac 14.61, pp608 */ 15 /* hac 14.61, pp608 */
19 int mp_invmod (mp_int * a, mp_int * b, mp_int * c) 16 int mp_invmod(const mp_int *a, const mp_int *b, mp_int *c)
20 { 17 {
21 /* b cannot be negative */ 18 /* b cannot be negative and has to be >1 */
22 if ((b->sign == MP_NEG) || (mp_iszero(b) == MP_YES)) { 19 if ((b->sign == MP_NEG) || (mp_cmp_d(b, 1uL) != MP_GT)) {
23 return MP_VAL; 20 return MP_VAL;
24 } 21 }
25 22
26 #ifdef BN_FAST_MP_INVMOD_C 23 #ifdef BN_FAST_MP_INVMOD_C
27 /* if the modulus is odd we can use a faster routine instead */ 24 /* if the modulus is odd we can use a faster routine instead */
28 if ((mp_isodd(b) == MP_YES) && (mp_cmp_d(b, 1) != MP_EQ)) { 25 if ((mp_isodd(b) == MP_YES)) {
29 return fast_mp_invmod (a, b, c); 26 return fast_mp_invmod(a, b, c);
30 } 27 }
31 #endif 28 #endif
32 29
33 #ifdef BN_MP_INVMOD_SLOW_C 30 #ifdef BN_MP_INVMOD_SLOW_C
34 return mp_invmod_slow(a, b, c); 31 return mp_invmod_slow(a, b, c);
35 #else 32 #else
36 return MP_VAL; 33 return MP_VAL;
37 #endif 34 #endif
38 } 35 }
39 #endif 36 #endif
40 37
41 /* ref: $Format:%D$ */ 38 /* ref: HEAD -> master, tag: v1.1.0 */
42 /* git commit: $Format:%H$ */ 39 /* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
43 /* commit time: $Format:%ai$ */ 40 /* commit time: 2019-01-28 20:32:32 +0100 */