Mercurial > dropbear
diff libtommath/bn_mp_read_signed_bin.c @ 389:5ff8218bcee9
propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 2af95f00ebd5bb7a28b3817db1218442c935388e)
to branch 'au.asn.ucc.matt.dropbear' (head ecd779509ef23a8cdf64888904fc9b31d78aa933)
author | Matt Johnston <matt@ucc.asn.au> |
---|---|
date | Thu, 11 Jan 2007 03:14:55 +0000 |
parents | eed26cff980b |
children | 60fc6476e044 |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/libtommath/bn_mp_read_signed_bin.c Thu Jan 11 03:14:55 2007 +0000 @@ -0,0 +1,41 @@ +#include <tommath.h> +#ifdef BN_MP_READ_SIGNED_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, [email protected], http://math.libtomcrypt.com + */ + +/* read signed bin, big endian, first byte is 0==positive or 1==negative */ +int mp_read_signed_bin (mp_int * a, const unsigned char *b, int c) +{ + int res; + + /* read magnitude */ + if ((res = mp_read_unsigned_bin (a, b + 1, c - 1)) != MP_OKAY) { + return res; + } + + /* first byte is 0 for positive, non-zero for negative */ + if (b[0] == 0) { + a->sign = MP_ZPOS; + } else { + a->sign = MP_NEG; + } + + return MP_OKAY; +} +#endif + +/* $Source: /cvs/libtom/libtommath/bn_mp_read_signed_bin.c,v $ */ +/* $Revision: 1.4 $ */ +/* $Date: 2006/03/31 14:18:44 $ */