diff options
author | Steffen Jaeckel <s@jaeckel.eu> | 2020-05-26 17:36:47 +0200 |
---|---|---|
committer | GitHub <noreply@github.com> | 2020-05-26 23:36:47 +0800 |
commit | b4bd23b4d2a4c640880b49069e02cd598dd03416 (patch) | |
tree | fb480b4e501cc69b305de95fb15259aa6afa1963 /libtommath/bn_mp_from_ubin.c | |
parent | 724e61f8ae9e9f216b0252e41c5ebd5d64ad79a6 (diff) |
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.
Diffstat (limited to 'libtommath/bn_mp_from_ubin.c')
-rw-r--r-- | libtommath/bn_mp_from_ubin.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/libtommath/bn_mp_from_ubin.c b/libtommath/bn_mp_from_ubin.c new file mode 100644 index 0000000..7f73cbc --- /dev/null +++ b/libtommath/bn_mp_from_ubin.c @@ -0,0 +1,39 @@ +#include "tommath_private.h" +#ifdef BN_MP_FROM_UBIN_C +/* LibTomMath, multiple-precision integer library -- Tom St Denis */ +/* SPDX-License-Identifier: Unlicense */ + +/* reads a unsigned char array, assumes the msb is stored first [big endian] */ +mp_err mp_from_ubin(mp_int *a, const unsigned char *buf, size_t size) +{ + mp_err err; + + /* make sure there are at least two digits */ + if (a->alloc < 2) { + if ((err = mp_grow(a, 2)) != MP_OKAY) { + return err; + } + } + + /* zero the int */ + mp_zero(a); + + /* read the bytes in */ + while (size-- > 0u) { + if ((err = mp_mul_2d(a, 8, a)) != MP_OKAY) { + return err; + } + +#ifndef MP_8BIT + a->dp[0] |= *buf++; + a->used += 1; +#else + a->dp[0] = (*buf & MP_MASK); + a->dp[1] |= ((*buf++ >> 7) & 1u); + a->used += 2; +#endif + } + mp_clamp(a); + return MP_OKAY; +} +#endif |