--- /dev/null
+/* 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.
+ */
+#include "tomcrypt.h"
+
+/**
+ Source donated by Elliptic Semiconductor Inc (www.ellipticsemi.com) to the LibTom Projects
+*/
+
+#ifdef LTC_XTS_MODE
+
+/** multiply by x
+ @param I The value to multiply by x (LFSR shift)
+*/
+void xts_mult_x(unsigned char *I)
+{
+ int x;
+ unsigned char t, tt;
+
+ for (x = t = 0; x < 16; x++) {
+ tt = I[x] >> 7;
+ I[x] = ((I[x] << 1) | t) & 0xFF;
+ t = tt;
+ }
+ if (tt) {
+ I[0] ^= 0x87;
+ }
+}
+
+#endif
+
+/* ref: $Format:%D$ */
+/* git commit: $Format:%H$ */
+/* commit time: $Format:%ai$ */