bn_mp_xor.c
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#include <tommath.h>
#ifdef BN_MP_XOR_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, tomstdenis@gmail.com, http://math.libtomcrypt.com
*/
/* XOR two ints together */
int
mp_xor (mp_int * a, mp_int * b, mp_int * c)
{
int res, ix, px;
mp_int t, *x;
if (a->used > b->used) {
if ((res = mp_init_copy (&t, a)) != MP_OKAY) {
return res;
}
px = b->used;
x = b;
} else {
if ((res = mp_init_copy (&t, b)) != MP_OKAY) {
return res;
}
px = a->used;
x = a;
}
for (ix = 0; ix < px; ix++) {
t.dp[ix] ^= x->dp[ix];
}
mp_clamp (&t);
mp_exch (c, &t);
mp_clear (&t);
return MP_OKAY;
}
#endif
/* $Source: /cvs/libtom/libtommath/bn_mp_xor.c,v $ */
/* $Revision: 1.3 $ */
/* $Date: 2006/03/31 14:18:44 $ */