diff options
Diffstat (limited to 'source4/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k_l.c')
-rw-r--r-- | source4/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k_l.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/source4/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k_l.c b/source4/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k_l.c new file mode 100644 index 0000000000..14a4d21846 --- /dev/null +++ b/source4/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k_l.c @@ -0,0 +1,44 @@ +#include <tommath.h> +#ifdef BN_MP_REDUCE_IS_2K_L_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@gmail.com, http://libtom.org + */ + +/* determines if reduce_2k_l can be used */ +int mp_reduce_is_2k_l(mp_int *a) +{ + int ix, iy; + + if (a->used == 0) { + return MP_NO; + } else if (a->used == 1) { + return MP_YES; + } else if (a->used > 1) { + /* if more than half of the digits are -1 we're sold */ + for (iy = ix = 0; ix < a->used; ix++) { + if (a->dp[ix] == MP_MASK) { + ++iy; + } + } + return (iy >= (a->used/2)) ? MP_YES : MP_NO; + + } + return MP_NO; +} + +#endif + +/* $Source: /cvs/libtom/libtommath/bn_mp_reduce_is_2k_l.c,v $ */ +/* $Revision: 1.4 $ */ +/* $Date: 2006/12/28 01:25:13 $ */ |