diff options
author | Matt Johnston <matt@ucc.asn.au> | 2006-03-08 13:23:49 +0000 |
---|---|---|
committer | Matt Johnston <matt@ucc.asn.au> | 2006-03-08 13:23:49 +0000 |
commit | 8608a8e64c1aeda096867f43f89e29e1aee207ae (patch) | |
tree | 453ebf8873dd287a2def6a674d42afcc6637cde2 /libtommath/bn_mp_neg.c | |
parent | 2481693cf23dba90c693762a528d2923cde9c9cc (diff) | |
parent | 882a9ced901348b3a48023443bfd23e0ef9d9b67 (diff) |
propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 6c790cad5a7fa866ad062cb3a0c279f7ba788583)
to branch 'au.asn.ucc.matt.dropbear' (head fff0894a0399405a9410ea1c6d118f342cf2aa64)
--HG--
extra : convert_revision : fdf4a7a3b97ae5046139915de7e40399cceb2c01
Diffstat (limited to 'libtommath/bn_mp_neg.c')
-rw-r--r-- | libtommath/bn_mp_neg.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/libtommath/bn_mp_neg.c b/libtommath/bn_mp_neg.c new file mode 100644 index 0000000..159cd74 --- /dev/null +++ b/libtommath/bn_mp_neg.c @@ -0,0 +1,36 @@ +#include <tommath.h> +#ifdef BN_MP_NEG_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 + */ + +/* b = -a */ +int mp_neg (mp_int * a, mp_int * b) +{ + int res; + if (a != b) { + if ((res = mp_copy (a, b)) != MP_OKAY) { + return res; + } + } + + if (mp_iszero(b) != MP_YES) { + b->sign = (a->sign == MP_ZPOS) ? MP_NEG : MP_ZPOS; + } else { + b->sign = MP_ZPOS; + } + + return MP_OKAY; +} +#endif |