1 #include <tommath.h> 2 #ifdef BN_MP_REDUCE_SETUP_C 3 /* LibTomMath, multiple-precision integer library -- Tom St Denis 4 * 5 * LibTomMath is a library that provides multiple-precision 6 * integer arithmetic as well as number theoretic functionality. 7 * 8 * The library was designed directly after the MPI library by 9 * Michael Fromberger but has been written from scratch with 10 * additional optimizations in place. 11 * 12 * The library is free for all purposes without any express 13 * guarantee it works. 14 * 15 * Tom St Denis, tomstdenis (at) gmail.com, http://math.libtomcrypt.com 16 */ 17 18 /* pre-calculate the value required for Barrett reduction 19 * For a given modulus "b" it calulates the value required in "a" 20 */ 21 int mp_reduce_setup (mp_int * a, mp_int * b) 22 { 23 int res; 24 25 if ((res = mp_2expt (a, b->used * 2 * DIGIT_BIT)) != MP_OKAY) { 26 return res; 27 } 28 return mp_div (a, b, a, NULL); 29 } 30 #endif 31 32 /* $Source: /cvs/libtom/libtommath/bn_mp_reduce_setup.c,v $ */ 33 /* $Revision: 1.3 $ */ 34 /* $Date: 2006/03/31 14:18:44 $ */ 35
