1 #include <tommath.h> 2 #ifdef BN_MP_AND_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 /* AND two ints together */ 19 int 20 mp_and (mp_int * a, mp_int * b, mp_int * c) 21 { 22 int res, ix, px; 23 mp_int t, *x; 24 25 if (a->used > b->used) { 26 if ((res = mp_init_copy (&t, a)) != MP_OKAY) { 27 return res; 28 } 29 px = b->used; 30 x = b; 31 } else { 32 if ((res = mp_init_copy (&t, b)) != MP_OKAY) { 33 return res; 34 } 35 px = a->used; 36 x = a; 37 } 38 39 for (ix = 0; ix < px; ix++) { 40 t.dp[ix] &= x->dp[ix]; 41 } 42 43 /* zero digits above the last from the smallest mp_int */ 44 for (; ix < t.used; ix++) { 45 t.dp[ix] = 0; 46 } 47 48 mp_clamp (&t); 49 mp_exch (c, &t); 50 mp_clear (&t); 51 return MP_OKAY; 52 } 53 #endif 54 55 /* $Source: /cvs/libtom/libtommath/bn_mp_and.c,v $ */ 56 /* $Revision: 1.3 $ */ 57 /* $Date: 2006/03/31 14:18:44 $ */ 58