kc3-lang/libtommath/bn_mp_invmod.c

• Show log

  Commit

• Hash : 079b0f65
  Author :
  Date : 2015-10-30T17:55:29
  

  Getting ready for v0.43.0 release Also updated my email address... Signed-off-by: Tom St Denis <tstdenis82@gmail.com>

Download

• bn_mp_invmod.c

• #include <tommath.h>
  #ifdef BN_MP_INVMOD_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, tstdenis82@gmail.com, http://libtom.org
   */
  
  /* hac 14.61, pp608 */
  int mp_invmod (mp_int * a, mp_int * b, mp_int * c)
  {
    /* b cannot be negative */
    if (b->sign == MP_NEG || mp_iszero(b) == 1) {
      return MP_VAL;
    }
  
  #ifdef BN_FAST_MP_INVMOD_C
    /* if the modulus is odd we can use a faster routine instead */
    if (mp_isodd (b) == 1) {
      return fast_mp_invmod (a, b, c);
    }
  #endif
  
  #ifdef BN_MP_INVMOD_SLOW_C
    return mp_invmod_slow(a, b, c);
  #else
    return MP_VAL;
  #endif
  }
  #endif
  
  /* $Source$ */
  /* $Revision$ */
  /* $Date$ */
  

Download