Mercurial > dropbear
view libtommath/bn_mp_set_int.c @ 1663:c795520269f9
Fallback for key gen without hard link support (#89)
Add a non-atomic fallback for key generation on platforms where link()
is not permitted (such as most stock Android installs) or on filesystems
without hard link support (such as FAT).
author | Matt Robinson <git@nerdoftheherd.com> |
---|---|
date | Sat, 14 Mar 2020 14:37:35 +0000 |
parents | f52919ffd3b1 |
children |
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#include "tommath_private.h" #ifdef BN_MP_SET_INT_C /* LibTomMath, multiple-precision integer library -- Tom St Denis * * LibTomMath is a library that provides multiple-precision * integer arithmetic as well as number theoretic functionality. * * The library was designed directly after the MPI library by * Michael Fromberger but has been written from scratch with * additional optimizations in place. * * SPDX-License-Identifier: Unlicense */ /* set a 32-bit const */ int mp_set_int(mp_int *a, unsigned long b) { int x, res; mp_zero(a); /* set four bits at a time */ for (x = 0; x < 8; x++) { /* shift the number up four bits */ if ((res = mp_mul_2d(a, 4, a)) != MP_OKAY) { return res; } /* OR in the top four bits of the source */ a->dp[0] |= (mp_digit)(b >> 28) & 15uL; /* shift the source up to the next four bits */ b <<= 4; /* ensure that digits are not clamped off */ a->used += 1; } mp_clamp(a); return MP_OKAY; } #endif /* ref: HEAD -> master, tag: v1.1.0 */ /* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */ /* commit time: 2019-01-28 20:32:32 +0100 */