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comparison libtommath/bn_mp_to_unsigned_bin.c @ 285:1b9e69c058d2

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propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 20dccfc09627970a312d77fb41dc2970b62689c3) to branch 'au.asn.ucc.matt.dropbear' (head fdf4a7a3b97ae5046139915de7e40399cceb2c01)
author Matt Johnston <matt@ucc.asn.au>
date Wed, 08 Mar 2006 13:23:58 +0000
parents eed26cff980b
children 5ff8218bcee9
comparison
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281:997e6f7dc01e 285:1b9e69c058d2
1 #include <tommath.h>
2 #ifdef BN_MP_TO_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, [email protected], http://math.libtomcrypt.org
16 */
17
18 /* store in unsigned [big endian] format */
19 int mp_to_unsigned_bin (mp_int * a, unsigned char *b)
20 {
21 int x, res;
22 mp_int t;
23
24 if ((res = mp_init_copy (&t, a)) != MP_OKAY) {
25 return res;
26 }
27
28 x = 0;
29 while (mp_iszero (&t) == 0) {
30 #ifndef MP_8BIT
31 b[x++] = (unsigned char) (t.dp[0] & 255);
32 #else
33 b[x++] = (unsigned char) (t.dp[0] | ((t.dp[1] & 0x01) << 7));
34 #endif
35 if ((res = mp_div_2d (&t, 8, &t, NULL)) != MP_OKAY) {
36 mp_clear (&t);
37 return res;
38 }
39 }
40 bn_reverse (b, x);
41 mp_clear (&t);
42 return MP_OKAY;
43 }
44 #endif