From ab6e3fce040f9ad27cbce44e9038a24f15b601c8 Mon Sep 17 00:00:00 2001 From: Matthieu Patou Date: Sun, 15 Aug 2010 18:31:28 +0400 Subject: s4:heimdal: import lorikeet-heimdal-201009250123 (commit 42cabfb5b683dbcb97d583c397b897507689e382) I based this on Matthieu's import of lorikeet-heimdal, and then updated it to this commit. Andrew Bartlett --- .../lib/hcrypto/libtommath/bn_mp_reduce_is_2k.c | 52 ++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 source4/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k.c (limited to 'source4/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k.c') diff --git a/source4/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k.c b/source4/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k.c new file mode 100644 index 0000000000..7308be73e2 --- /dev/null +++ b/source4/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k.c @@ -0,0 +1,52 @@ +#include +#ifdef BN_MP_REDUCE_IS_2K_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 mp_reduce_2k can be used */ +int mp_reduce_is_2k(mp_int *a) +{ + int ix, iy, iw; + mp_digit iz; + + if (a->used == 0) { + return MP_NO; + } else if (a->used == 1) { + return MP_YES; + } else if (a->used > 1) { + iy = mp_count_bits(a); + iz = 1; + iw = 1; + + /* Test every bit from the second digit up, must be 1 */ + for (ix = DIGIT_BIT; ix < iy; ix++) { + if ((a->dp[iw] & iz) == 0) { + return MP_NO; + } + iz <<= 1; + if (iz > (mp_digit)MP_MASK) { + ++iw; + iz = 1; + } + } + } + return MP_YES; +} + +#endif + +/* $Source: /cvs/libtom/libtommath/bn_mp_reduce_is_2k.c,v $ */ +/* $Revision: 1.4 $ */ +/* $Date: 2006/12/28 01:25:13 $ */ -- cgit