--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/encauth/ocb/ocb_shift_xor.c	Wed Mar 08 12:58:00 2006 +0000
@@ -0,0 +1,39 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, [email protected], http://libtomcrypt.org
+ */
+
+/** 
+   @file ocb_shift_xor.c
+   OCB implementation, internal function, by Tom St Denis
+*/
+#include "tomcrypt.h"
+
+#ifdef OCB_MODE
+
+/**
+   Compute the shift/xor for OCB (internal function)
+   @param ocb  The OCB state 
+   @param Z    The destination of the shift
+*/
+void ocb_shift_xor(ocb_state *ocb, unsigned char *Z)
+{
+   int x, y;
+   y = ocb_ntz(ocb->block_index++);
+   for (x = 0; x < ocb->block_len; x++) {
+       ocb->Li[x] ^= ocb->Ls[y][x];
+       Z[x]        = ocb->Li[x] ^ ocb->R[x];
+   }
+}
+
+#endif
+
+/* $Source: /cvs/libtom/libtomcrypt/src/encauth/ocb/ocb_shift_xor.c,v $ */
+/* $Revision: 1.3 $ */
+/* $Date: 2005/05/05 14:35:58 $ */