1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis 2 * 3 * LibTomCrypt is a library that provides various cryptographic 4 * algorithms in a highly modular and flexible manner. 5 * 6 * The library is free for all purposes without any express 7 * guarantee it works. 8 * 9 * Tom St Denis, tomstdenis (at) gmail.com, http://libtomcrypt.com 10 */ 11 #include "tomcrypt.h" 12 13 /** 14 @file pmac_shift_xor.c 15 PMAC implementation, internal function, by Tom St Denis 16 */ 17 18 #ifdef LTC_PMAC 19 20 /** 21 Internal function. Performs the state update (adding correct multiple) 22 @param pmac The PMAC state. 23 */ 24 void pmac_shift_xor(pmac_state *pmac) 25 { 26 int x, y; 27 y = pmac_ntz(pmac->block_index++); 28 #ifdef LTC_FAST 29 for (x = 0; x < pmac->block_len; x += sizeof(LTC_FAST_TYPE)) { 30 *((LTC_FAST_TYPE*)((unsigned char *)pmac->Li + x)) ^= 31 *((LTC_FAST_TYPE*)((unsigned char *)pmac->Ls[y] + x)); 32 } 33 #else 34 for (x = 0; x < pmac->block_len; x++) { 35 pmac->Li[x] ^= pmac->Ls[y][x]; 36 } 37 #endif 38 } 39 40 #endif 41 42 /* $Source: /cvs/libtom/libtomcrypt/src/mac/pmac/pmac_shift_xor.c,v $ */ 43 /* $Revision: 1.6 $ */ 44 /* $Date: 2006/11/03 00:39:49 $ */ 45
