1 #include <tommath.h> 2 #ifdef BN_MP_SUBMOD_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 /* d = a - b (mod c) */ 19 int 20 mp_submod (mp_int * a, mp_int * b, mp_int * c, mp_int * d) 21 { 22 int res; 23 mp_int t; 24 25 26 if ((res = mp_init (&t)) != MP_OKAY) { 27 return res; 28 } 29 30 if ((res = mp_sub (a, b, &t)) != MP_OKAY) { 31 mp_clear (&t); 32 return res; 33 } 34 res = mp_mod (&t, c, d); 35 mp_clear (&t); 36 return res; 37 } 38 #endif 39 40 /* $Source: /cvs/libtom/libtommath/bn_mp_submod.c,v $ */ 41 /* $Revision: 1.3 $ */ 42 /* $Date: 2006/03/31 14:18:44 $ */ 43
