Mercurial > dropbear
diff libtommath/bn_mp_from_sbin.c @ 1692:1051e4eea25a
Update LibTomMath to 1.2.0 (#84)
* update C files
* update other files
* update headers
* update makefiles
* remove mp_set/get_double()
* use ltm 1.2.0 API
* update ltm_desc
* use bundled tommath if system-tommath is too old
* XMALLOC etc. were changed to MP_MALLOC etc.
author | Steffen Jaeckel <s@jaeckel.eu> |
---|---|
date | Tue, 26 May 2020 17:36:47 +0200 |
parents | |
children |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/libtommath/bn_mp_from_sbin.c Tue May 26 17:36:47 2020 +0200 @@ -0,0 +1,25 @@ +#include "tommath_private.h" +#ifdef BN_MP_FROM_SBIN_C +/* LibTomMath, multiple-precision integer library -- Tom St Denis */ +/* SPDX-License-Identifier: Unlicense */ + +/* read signed bin, big endian, first byte is 0==positive or 1==negative */ +mp_err mp_from_sbin(mp_int *a, const unsigned char *buf, size_t size) +{ + mp_err err; + + /* read magnitude */ + if ((err = mp_from_ubin(a, buf + 1, size - 1u)) != MP_OKAY) { + return err; + } + + /* first byte is 0 for positive, non-zero for negative */ + if (buf[0] == (unsigned char)0) { + a->sign = MP_ZPOS; + } else { + a->sign = MP_NEG; + } + + return MP_OKAY; +} +#endif