Mercurial > dropbear
view libtommath/bn_mp_signed_rsh.c @ 1702:8f93f37c01de
Allow DH to be completely disabled (#97)
Reduces binary size by ~2kB by default and by 21kB with no other
libtommath functions users, ex. with curve25519 kex and ed25519
key only.
author | Vladislav Grishenko <themiron@users.noreply.github.com> |
---|---|
date | Thu, 28 May 2020 20:01:48 +0500 |
parents | 1051e4eea25a |
children |
line wrap: on
line source
#include "tommath_private.h" #ifdef BN_MP_SIGNED_RSH_C /* LibTomMath, multiple-precision integer library -- Tom St Denis */ /* SPDX-License-Identifier: Unlicense */ /* shift right by a certain bit count with sign extension */ mp_err mp_signed_rsh(const mp_int *a, int b, mp_int *c) { mp_err res; if (a->sign == MP_ZPOS) { return mp_div_2d(a, b, c, NULL); } res = mp_add_d(a, 1uL, c); if (res != MP_OKAY) { return res; } res = mp_div_2d(c, b, c, NULL); return (res == MP_OKAY) ? mp_sub_d(c, 1uL, c) : res; } #endif