Mercurial > dropbear
view libtommath/bn_mp_reduce_is_2k.c @ 1385:6c92e97553f1 fuzz
Add a flag whether to longjmp, missed that last commit
author | Matt Johnston <matt@ucc.asn.au> |
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date | Thu, 01 Jun 2017 21:30:26 +0800 |
parents | 5ff8218bcee9 |
children | 60fc6476e044 |
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#include <tommath.h> #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, [email protected], http://math.libtomcrypt.com */ /* 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: 1.3 $ */ /* $Date: 2006/03/31 14:18:44 $ */