43 lines
988 B
C
43 lines
988 B
C
#include <tommath_private.h>
|
|
#ifdef BN_MP_SUBMOD_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
|
|
*/
|
|
|
|
/* d = a - b (mod c) */
|
|
int
|
|
mp_submod (mp_int * a, mp_int * b, mp_int * c, mp_int * d)
|
|
{
|
|
int res;
|
|
mp_int t;
|
|
|
|
|
|
if ((res = mp_init (&t)) != MP_OKAY) {
|
|
return res;
|
|
}
|
|
|
|
if ((res = mp_sub (a, b, &t)) != MP_OKAY) {
|
|
mp_clear (&t);
|
|
return res;
|
|
}
|
|
res = mp_mod (&t, c, d);
|
|
mp_clear (&t);
|
|
return res;
|
|
}
|
|
#endif
|
|
|
|
/* ref: $Format:%D$ */
|
|
/* git commit: $Format:%H$ */
|
|
/* commit time: $Format:%ai$ */
|