/src/dropbear/libtommath/bn_mp_submod.c
Line | Count | Source (jump to first uncovered line) |
1 | | #include "tommath_private.h" |
2 | | #ifdef BN_MP_SUBMOD_C |
3 | | /* LibTomMath, multiple-precision integer library -- Tom St Denis */ |
4 | | /* SPDX-License-Identifier: Unlicense */ |
5 | | |
6 | | /* d = a - b (mod c) */ |
7 | | mp_err mp_submod(const mp_int *a, const mp_int *b, const mp_int *c, mp_int *d) |
8 | 0 | { |
9 | 0 | mp_err err; |
10 | 0 | mp_int t; |
11 | |
|
12 | 0 | if ((err = mp_init(&t)) != MP_OKAY) { |
13 | 0 | return err; |
14 | 0 | } |
15 | | |
16 | 0 | if ((err = mp_sub(a, b, &t)) != MP_OKAY) { |
17 | 0 | goto LBL_ERR; |
18 | 0 | } |
19 | 0 | err = mp_mod(&t, c, d); |
20 | |
|
21 | 0 | LBL_ERR: |
22 | 0 | mp_clear(&t); |
23 | 0 | return err; |
24 | 0 | } |
25 | | #endif |