bn_mp_xor.c revision f7fc46c63fdc8f39234fea409b8dbe116d73ebf8
1f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#include <tommath.h> 2f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#ifdef BN_MP_XOR_C 3f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* LibTomMath, multiple-precision integer library -- Tom St Denis 4f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * 5f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * LibTomMath is a library that provides multiple-precision 6f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * integer arithmetic as well as number theoretic functionality. 7f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * 8f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * The library was designed directly after the MPI library by 9f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * Michael Fromberger but has been written from scratch with 10f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * additional optimizations in place. 11f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * 12f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * The library is free for all purposes without any express 13f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * guarantee it works. 14f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * 15f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project * Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com 16f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project */ 17f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 18f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* XOR two ints together */ 19f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectint 20f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Projectmp_xor (mp_int * a, mp_int * b, mp_int * c) 21f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project{ 22f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project int res, ix, px; 23f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project mp_int t, *x; 24f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 25f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if (a->used > b->used) { 26f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if ((res = mp_init_copy (&t, a)) != MP_OKAY) { 27f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return res; 28f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 29f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project px = b->used; 30f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x = b; 31f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } else { 32f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project if ((res = mp_init_copy (&t, b)) != MP_OKAY) { 33f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return res; 34f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 35f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project px = a->used; 36f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project x = a; 37f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 38f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 39f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project for (ix = 0; ix < px; ix++) { 40f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project t.dp[ix] ^= x->dp[ix]; 41f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project } 42f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project mp_clamp (&t); 43f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project mp_exch (c, &t); 44f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project mp_clear (&t); 45f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project return MP_OKAY; 46f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project} 47f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project#endif 48f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project 49f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Source: /cvs/libtom/libtommath/bn_mp_xor.c,v $ */ 50f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Revision: 1.3 $ */ 51f7fc46c63fdc8f39234fea409b8dbe116d73ebf8The Android Open Source Project/* $Date: 2006/03/31 14:18:44 $ */ 52