Line data Source code
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://libtom.org
16 : */
17 :
18 : /* reads a unsigned char array, assumes the msb is stored first [big endian] */
19 2616 : int 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 2616 : if (a->alloc < 2) {
25 0 : if ((res = mp_grow(a, 2)) != MP_OKAY) {
26 0 : return res;
27 : }
28 : }
29 :
30 : /* zero the int */
31 2616 : mp_zero (a);
32 :
33 : /* read the bytes in */
34 746952 : while (c-- > 0) {
35 741720 : if ((res = mp_mul_2d (a, 8, a)) != MP_OKAY) {
36 0 : return res;
37 : }
38 :
39 : #ifndef MP_8BIT
40 741720 : a->dp[0] |= *b++;
41 741720 : 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 2616 : mp_clamp (a);
49 2616 : return MP_OKAY;
50 : }
51 : #endif
52 :
53 : /* $Source: /cvs/libtom/libtommath/bn_mp_read_unsigned_bin.c,v $ */
54 : /* $Revision: 1.5 $ */
55 : /* $Date: 2006/12/28 01:25:13 $ */
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