view libtommath/bn_mp_reduce_2k_setup_l.c @ 297:79bf1023cf11 agent-client

propagate from branch 'au.asn.ucc.matt.dropbear' (head 0501e6f661b5415eb76f3b312d183c3adfbfb712) to branch 'au.asn.ucc.matt.dropbear.cli-agent' (head 01038174ec27245b51bd43a66c01ad930880f67b)
author Matt Johnston <matt@ucc.asn.au>
date Tue, 21 Mar 2006 16:20:59 +0000
parents eed26cff980b
children 5ff8218bcee9
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#include <tommath.h>
#ifdef BN_MP_REDUCE_2K_SETUP_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, [email protected], http://math.libtomcrypt.org
 */

/* determines the setup value */
int mp_reduce_2k_setup_l(mp_int *a, mp_int *d)
{
   int    res;
   mp_int tmp;
   
   if ((res = mp_init(&tmp)) != MP_OKAY) {
      return res;
   }
   
   if ((res = mp_2expt(&tmp, mp_count_bits(a))) != MP_OKAY) {
      goto ERR;
   }
   
   if ((res = s_mp_sub(&tmp, a, d)) != MP_OKAY) {
      goto ERR;
   }
   
ERR:
   mp_clear(&tmp);
   return res;
}
#endif