diff options
author | Matt Johnston <matt@ucc.asn.au> | 2006-03-08 13:16:18 +0000 |
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committer | Matt Johnston <matt@ucc.asn.au> | 2006-03-08 13:16:18 +0000 |
commit | 1c5fda515f96c27d4e3b732d887f418453f1cb14 (patch) | |
tree | bf90196389a9618de48c5acb5ce1d056aa347ce0 /bn_mp_to_unsigned_bin.c |
Import of libtommath 0.35
From ltm-0.35.tar.bz2 SHA1 of 3f193dbae9351e92d02530994fa18236f7fde01c
--HG--
branch : libtommath-orig
extra : convert_revision : 2b4b13ac88b2a81e5c86ba868c92c6a452630e02
Diffstat (limited to 'bn_mp_to_unsigned_bin.c')
-rw-r--r-- | bn_mp_to_unsigned_bin.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/bn_mp_to_unsigned_bin.c b/bn_mp_to_unsigned_bin.c new file mode 100644 index 0000000..000967e --- /dev/null +++ b/bn_mp_to_unsigned_bin.c @@ -0,0 +1,44 @@ +#include <tommath.h> +#ifdef BN_MP_TO_UNSIGNED_BIN_C +/* LibTomMath, multiple-precision integer library -- Tom St Denis + * + * LibTomMath is a library that provides multiple-precision + * integer arithmetic as well as number theoretic functionality. + * + * The library was designed directly after the MPI library by + * Michael Fromberger but has been written from scratch with + * additional optimizations in place. + * + * The library is free for all purposes without any express + * guarantee it works. + * + * Tom St Denis, tomstdenis@iahu.ca, http://math.libtomcrypt.org + */ + +/* store in unsigned [big endian] format */ +int mp_to_unsigned_bin (mp_int * a, unsigned char *b) +{ + int x, res; + mp_int t; + + if ((res = mp_init_copy (&t, a)) != MP_OKAY) { + return res; + } + + x = 0; + while (mp_iszero (&t) == 0) { +#ifndef MP_8BIT + b[x++] = (unsigned char) (t.dp[0] & 255); +#else + b[x++] = (unsigned char) (t.dp[0] | ((t.dp[1] & 0x01) << 7)); +#endif + if ((res = mp_div_2d (&t, 8, &t, NULL)) != MP_OKAY) { + mp_clear (&t); + return res; + } + } + bn_reverse (b, x); + mp_clear (&t); + return MP_OKAY; +} +#endif |