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 12 /** 13 @file ocb_shift_xor.c 14 OCB implementation, internal function, by Tom St Denis 15 */ 16 #include "tomcrypt.h" 17 18 #ifdef OCB_MODE 19 20 /** 21 Compute the shift/xor for OCB (internal function) 22 @param ocb The OCB state 23 @param Z The destination of the shift 24 */ 25 void ocb_shift_xor(ocb_state *ocb, unsigned char *Z) 26 { 27 int x, y; 28 y = ocb_ntz(ocb->block_index++); 29 for (x = 0; x < ocb->block_len; x++) { 30 ocb->Li[x] ^= ocb->Ls[y][x]; 31 Z[x] = ocb->Li[x] ^ ocb->R[x]; 32 } 33 } 34 35 #endif 36 37 /* $Source: /cvs/libtom/libtomcrypt/src/encauth/ocb/ocb_shift_xor.c,v $ */ 38 /* $Revision: 1.4 $ */ 39 /* $Date: 2006/03/31 14:15:35 $ */ 40
