1#include <tommath.h>
2#ifdef BN_MP_READ_UNSIGNED_BIN_C
3/* LibTomMath, multiple-precision integer library -- Tom St Denis
4 *
5 * LibTomMath is a library that provides multiple-precision
6 * integer arithmetic as well as number theoretic functionality.
7 *
8 * The library was designed directly after the MPI library by
9 * Michael Fromberger but has been written from scratch with
10 * additional optimizations in place.
11 *
12 * The library is free for all purposes without any express
13 * guarantee it works.
14 *
15 * Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com
16 */
17
18/* reads a unsigned char array, assumes the msb is stored first [big endian] */
19int mp_read_unsigned_bin (mp_int * a, const unsigned char *b, int c)
20{
21  int     res;
22
23  /* make sure there are at least two digits */
24  if (a->alloc < 2) {
25     if ((res = mp_grow(a, 2)) != MP_OKAY) {
26        return res;
27     }
28  }
29
30  /* zero the int */
31  mp_zero (a);
32
33  /* read the bytes in */
34  while (c-- > 0) {
35    if ((res = mp_mul_2d (a, 8, a)) != MP_OKAY) {
36      return res;
37    }
38
39#ifndef MP_8BIT
40      a->dp[0] |= *b++;
41      a->used += 1;
42#else
43      a->dp[0] = (*b & MP_MASK);
44      a->dp[1] |= ((*b++ >> 7U) & 1);
45      a->used += 2;
46#endif
47  }
48  mp_clamp (a);
49  return MP_OKAY;
50}
51#endif
52
53/* $Source: /cvs/libtom/libtommath/bn_mp_read_unsigned_bin.c,v $ */
54/* $Revision: 1.4 $ */
55/* $Date: 2006/03/31 14:18:44 $ */
56