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/* 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, tomstdenis@gmail.com, http://libtom.org
*/
#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
/* $Source$ */
/* $Revision$ */
/* $Date$ */
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