Mercurial > dropbear

comparison bn_mp_read_signed_bin.c @ 2:86e0b50a9b58 libtommath-orig ltm-0.30-orig

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
ltm 0.30 orig import
author Matt Johnston <matt@ucc.asn.au>
date Mon, 31 May 2004 18:25:22 +0000
parents
children d29b64170cf0
comparison
equal deleted inserted replaced
-1:000000000000 2:86e0b50a9b58
1 /* LibTomMath, multiple-precision integer library -- Tom St Denis
2 *
3 * LibTomMath is a library that provides multiple-precision
4 * integer arithmetic as well as number theoretic functionality.
5 *
6 * The library was designed directly after the MPI library by
7 * Michael Fromberger but has been written from scratch with
8 * additional optimizations in place.
9 *
10 * The library is free for all purposes without any express
11 * guarantee it works.
12 *
13 * Tom St Denis, [email protected], http://math.libtomcrypt.org
14 */
15 #include <tommath.h>
16
17 /* read signed bin, big endian, first byte is 0==positive or 1==negative */
18 int
19 mp_read_signed_bin (mp_int * a, unsigned char *b, int c)
20 {
21 int res;
22
23 /* read magnitude */
24 if ((res = mp_read_unsigned_bin (a, b + 1, c - 1)) != MP_OKAY) {
25 return res;
26 }
27
28 /* first byte is 0 for positive, non-zero for negative */
29 if (b[0] == 0) {
30 a->sign = MP_ZPOS;
31 } else {
32 a->sign = MP_NEG;
33 }
34
35 return MP_OKAY;
36 }