Mercurial > dropbear
view bn_mp_mod.c @ 283:bd240aa12ba7 libtommath-dropbear
* Changes imported from Dropbear 0.47.
* bn_mp_clear.c is changed so that some vars are volatile,
so that the compiler won't optimise away
author | Matt Johnston <matt@ucc.asn.au> |
---|---|
date | Wed, 08 Mar 2006 13:22:52 +0000 |
parents | 91fbc376f010 |
children | 97db060d0ef5 |
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#include <tommath.h> #ifdef BN_MP_MOD_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.org */ /* c = a mod b, 0 <= c < b */ int mp_mod (mp_int * a, mp_int * b, mp_int * c) { mp_int t; int res; if ((res = mp_init (&t)) != MP_OKAY) { return res; } if ((res = mp_div (a, b, NULL, &t)) != MP_OKAY) { mp_clear (&t); return res; } if (t.sign != b->sign) { res = mp_add (b, &t, c); } else { res = MP_OKAY; mp_exch (&t, c); } mp_clear (&t); return res; } #endif