crypto/external/bsd/heimdal/dist/lib/hcrypto/libtommath/bn_mp_mod.c

   1 /*      $NetBSD: bn_mp_mod.c,v 1.1.1.2 2014/04/24 12:45:31 pettai Exp $ */
   2
   3 #include <tommath.h>
   4 #ifdef BN_MP_MOD_C
   5 /* LibTomMath, multiple-precision integer library -- Tom St Denis
   6  *
   7  * LibTomMath is a library that provides multiple-precision
   8  * integer arithmetic as well as number theoretic functionality.
   9  *
  10  * The library was designed directly after the MPI library by
  11  * Michael Fromberger but has been written from scratch with
  12  * additional optimizations in place.
  13  *
  14  * The library is free for all purposes without any express
  15  * guarantee it works.
  16  *
  17  * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
  18  */
  19
  20 /* c = a mod b, 0 <= c < b */
  21 int
  22 mp_mod (mp_int * a, mp_int * b, mp_int * c)
  23 {
  24   mp_int  t;
  25   int     res;
  26
  27   if ((res = mp_init (&t)) != MP_OKAY) {
  28     return res;
  29   }
  30
  31   if ((res = mp_div (a, b, NULL, &t)) != MP_OKAY) {
  32     mp_clear (&t);
  33     return res;
  34   }
  35
  36   if (t.sign != b->sign) {
  37     res = mp_add (b, &t, c);
  38   } else {
  39     res = MP_OKAY;
  40     mp_exch (&t, c);
  41   }
  42
  43   mp_clear (&t);
  44   return res;
  45 }
  46 #endif
  47
  48 /* Source: /cvs/libtom/libtommath/bn_mp_mod.c,v  */
  49 /* Revision: 1.4  */
  50 /* Date: 2006/12/28 01:25:13  */