/* pkcs11.h include file for PKCS #11. */
/* $Revision: 1.4 $ */

/* License to copy and use this software is granted provided that it is
 * identified as "RSA Security Inc. PKCS #11 Cryptographic Token Interface
 * (Cryptoki)" in all material mentioning or referencing this software.

 * License is also granted to make and use derivative works provided that
 * such works are identified as "derived from the RSA Security Inc. PKCS #11
 * Cryptographic Token Interface (Cryptoki)" in all material mentioning or
 * referencing the derived work.

 * RSA Security Inc. makes no representations concerning either the
 * merchantability of this software or the suitability of this software for
 * any particular purpose. It is provided "as is" without express or implied
 * warranty of any kind.
 */

#ifndef _PKCS11_H_
#define _PKCS11_H_ 1

#ifdef __cplusplus
extern "C" {
#endif

/* Before including this file (pkcs11.h) (or pkcs11t.h by
 * itself), 6 platform-specific macros must be defined.  These
 * macros are described below, and typical definitions for them
 * are also given.  Be advised that these definitions can depend
 * on both the platform and the compiler used (and possibly also
 * on whether a Cryptoki library is linked statically or
 * dynamically).
 *
 * In addition to defining these 6 macros, the packing convention
 * for Cryptoki structures should be set.  The Cryptoki
 * convention on packing is that structures should be 1-byte
 * aligned.
 *
 * If you're using Microsoft Developer Studio 5.0 to produce
 * Win32 stuff, this might be done by using the following
 * preprocessor directive before including pkcs11.h or pkcs11t.h:
 *
 * #pragma pack(push, cryptoki, 1)
 *
 * and using the following preprocessor directive after including
 * pkcs11.h or pkcs11t.h:
 *
 * #pragma pack(pop, cryptoki)
 *
 * If you're using an earlier version of Microsoft Developer
 * Studio to produce Win16 stuff, this might be done by using
 * the following preprocessor directive before including
 * pkcs11.h or pkcs11t.h:
 *
 * #pragma pack(1)
 *
 * In a UNIX environment, you're on your own for this.  You might
 * not need to do (or be able to do!) anything.
 *
 *
 * Now for the macros:
 *
 *
 * 1. CK_PTR: The indirection string for making a pointer to an
 * object.  It can be used like this:
 *
 * typedef CK_BYTE CK_PTR CK_BYTE_PTR;
 *
 * If you're using Microsoft Developer Studio 5.0 to produce
 * Win32 stuff, it might be defined by:
 *
 * #define CK_PTR *
 *
 * If you're using an earlier version of Microsoft Developer
 * Studio to produce Win16 stuff, it might be defined by:
 *
 * #define CK_PTR far *
 *
 * In a typical UNIX environment, it might be defined by:
 *
 * #define CK_PTR *
 *
 *
 * 2. CK_DEFINE_FUNCTION(returnType, name): A macro which makes
 * an exportable Cryptoki library function definition out of a
 * return type and a function name.  It should be used in the
 * following fashion to define the exposed Cryptoki functions in
 * a Cryptoki library:
 *
 * CK_DEFINE_FUNCTION(CK_RV, C_Initialize)(
 *   CK_VOID_PTR pReserved
 * )
 * {
 *   ...
 * }
 *
 * If you're using Microsoft Developer Studio 5.0 to define a
 * function in a Win32 Cryptoki .dll, it might be defined by:
 *
 * #define CK_DEFINE_FUNCTION(returnType, name) \
 *   returnType __declspec(dllexport) name
 *
 * If you're using an earlier version of Microsoft Developer
 * Studio to define a function in a Win16 Cryptoki .dll, it
 * might be defined by:
 *
 * #define CK_DEFINE_FUNCTION(returnType, name) \
 *   returnType __export _far _pascal name
 *
 * In a UNIX environment, it might be defined by:
 *
 * #define CK_DEFINE_FUNCTION(returnType, name) \
 *   returnType name
 *
 *
 * 3. CK_DECLARE_FUNCTION(returnType, name): A macro which makes
 * an importable Cryptoki library function declaration out of a
 * return type and a function name.  It should be used in the
 * following fashion:
 *
 * extern CK_DECLARE_FUNCTION(CK_RV, C_Initialize)(
 *   CK_VOID_PTR pReserved
 * );
 *
 * If you're using Microsoft Developer Studio 5.0 to declare a
 * function in a Win32 Cryptoki .dll, it might be defined by:
 *
 * #define CK_DECLARE_FUNCTION(returnType, name) \
 *   returnType __declspec(dllimport) name
 *
 * If you're using an earlier version of Microsoft Developer
 * Studio to declare a function in a Win16 Cryptoki .dll, it
 * might be defined by:
 *
 * #define CK_DECLARE_FUNCTION(returnType, name) \
 *   returnType __export _far _pascal name
 *
 * In a UNIX environment, it might be defined by:
 *
 * #define CK_DECLARE_FUNCTION(returnType, name) \
 *   returnType name
 *
 *
 * 4. CK_DECLARE_FUNCTION_POINTER(returnType, name): A macro
 * which makes a Cryptoki API function pointer declaration or
 * function pointer type declaration out of a return type and a
 * function name.  It should be used in the following fashion:
 *
 * // Define funcPtr to be a pointer to a Cryptoki API function
 * // taking arguments args and returning CK_RV.
 * CK_DECLARE_FUNCTION_POINTER(CK_RV, funcPtr)(args);
 *
 * or
 *
 * // Define funcPtrType to be the type of a pointer to a
 * // Cryptoki API function taking arguments args and returning
 * // CK_RV, and then define funcPtr to be a variable of type
 * // funcPtrType.
 * typedef CK_DECLARE_FUNCTION_POINTER(CK_RV, funcPtrType)(args);
 * funcPtrType funcPtr;
 *
 * If you're using Microsoft Developer Studio 5.0 to access
 * functions in a Win32 Cryptoki .dll, in might be defined by:
 *
 * #define CK_DECLARE_FUNCTION_POINTER(returnType, name) \
 *   returnType __declspec(dllimport) (* name)
 *
 * If you're using an earlier version of Microsoft Developer
 * Studio to access functions in a Win16 Cryptoki .dll, it might
 * be defined by:
 *
 * #define CK_DECLARE_FUNCTION_POINTER(returnType, name) \
 *   returnType __export _far _pascal (* name)
 *
 * In a UNIX environment, it might be defined by:
 *
 * #define CK_DECLARE_FUNCTION_POINTER(returnType, name) \
 *   returnType (* name)
 *
 *
 * 5. CK_CALLBACK_FUNCTION(returnType, name): A macro which makes
 * a function pointer type for an application callback out of
 * a return type for the
/*
 Derived from source code of TrueCrypt 7.1a, which is
 Copyright (c) 2008-2012 TrueCrypt Developers Association and which is governed
 by the TrueCrypt License 3.0.

 Modifications and additions to the original source code (contained in this file)
 and all other portions of this file are Copyright (c) 2013-2017 IDRIX
 and are governed by the Apache License 2.0 the full text of which is
 contained in the file License.txt included in VeraCrypt binary and source
 code distribution packages.
*/

/* If native 64-bit data types are not available, define TC_NO_COMPILER_INT64.

For big-endian platforms define BYTE_ORDER as BIG_ENDIAN. */


#ifdef TC_MINIMIZE_CODE_SIZE
//	Preboot/boot version
#	ifndef TC_NO_COMPILER_INT64
#		define TC_NO_COMPILER_INT64
#	endif
#	pragma optimize ("tl", on)
#endif

#ifdef TC_NO_COMPILER_INT64
#	include <memory.h>
#endif

#include "Xts.h"


#ifndef TC_NO_COMPILER_INT64

// length: number of bytes to encrypt; may be larger than one data unit and must be divisible by the cipher block size
// ks: the primary key schedule
// ks2: the secondary key schedule
// startDataUnitNo: The sequential number of the data unit with which the buffer starts.
// startCipherBlockNo: The sequential number of the first plaintext block to encrypt inside the data unit startDataUnitNo.
//                     When encrypting the data unit from its first block, startCipherBlockNo is 0.
//                     The startCipherBlockNo value applies only to the first data unit in the buffer; each successive
//                     data unit is encrypted from its first block. The start of the buffer does not have to be
//                     aligned with the start of a data unit. If it is aligned, startCipherBlockNo must be 0; if it
//                     is not aligned, startCipherBlockNo must reflect the misalignment accordingly.
void EncryptBufferXTS (unsigned __int8 *buffer,
					   TC_LARGEST_COMPILER_UINT length,
					   const UINT64_STRUCT *startDataUnitNo,
					   unsigned int startCipherBlockNo,
					   unsigned __int8 *ks,
					   unsigned __int8 *ks2,
					   int cipher)
{
	if (CipherSupportsIntraDataUnitParallelization (cipher))
		EncryptBufferXTSParallel (buffer, length, startDataUnitNo, startCipherBlockNo, ks, ks2, cipher);
	else
		EncryptBufferXTSNonParallel (buffer, length, startDataUnitNo, startCipherBlockNo, ks, ks2, cipher);
}


// Optimized for encryption algorithms supporting intra-data-unit parallelization
static void EncryptBufferXTSParallel (unsigned __int8 *buffer,
					   TC_LARGEST_COMPILER_UINT length,
					   const UINT64_STRUCT *startDataUnitNo,
					   unsigned int startCipherBlockNo,
					   unsigned __int8 *ks,
					   unsigned __int8 *ks2,
					   int cipher)
{
	unsigned __int8 finalCarry;
	unsigned __int8 whiteningValues [ENCRYPTION_DATA_UNIT_SIZE];
	CRYPTOPP_ALIGN_DATA(16) unsigned __int8 whiteningValue [BYTES_PER_XTS_BLOCK];
	unsigned __int8 byteBufUnitNo [BYTES_PER_XTS_BLOCK];
	unsigned __int64 *whiteningValuesPtr64 = (unsigned __int64 *) whiteningValues;
	unsigned __int64 *whiteningValuePtr64 = (unsigned __int64 *) whiteningValue;
	unsigned __int64 *bufPtr = (unsigned __int64 *) buffer;
	unsigned __int64 *dataUnitBufPtr;
	unsigned int startBlock = startCipherBlockNo, endBlock, block;
	unsigned __int64 *const finalInt64WhiteningValuesPtr = whiteningValuesPtr64 + sizeof (whiteningValues) / sizeof (*whiteningValuesPtr64) - 1;
	TC_LARGEST_COMPILER_UINT blockCount, dataUnitNo;

	/* The encrypted data unit number (i.e. the resultant ciphertext block) is to be multiplied in the
	finite field GF(2^128) by j-th power of n, where j is the sequential plaintext/ciphertext block
	number and n is 2, a primitive element of GF(2^128). This can be (and is) simplified and implemented
	as a left shift of the preceding whitening value by one bit (with carry propagating). In addition, if
	the shift of the highest byte results in a carry, 135 is XORed into the lowest byte. The value 135 is
	derived from the modulus of the Galois Field (x^128+x^7+x^2+x+1). */

	// Convert the 64-bit data unit number into a little-endian 16-byte array.
	// Note that as we are converting a 64-bit number into a 16-byte array we can always zero the last 8 bytes.
	dataUnitNo = startDataUnitNo->Value;
	*((unsigned __int64 *) byteBufUnitNo) = LE64 (dataUnitNo);
	*((unsigned __int64 *) byteBufUnitNo + 1) = 0;

	if (length % BYTES_PER_XTS_BLOCK)
		TC_THROW_FATAL_EXCEPTION;

	blockCount = length / BYTES_PER_XTS_BLOCK;

	// Process all blocks in the buffer
	while (blockCount > 0)
	{
		if (blockCount < BLOCKS_PER_XTS_DATA_UNIT)
			endBlock = startBlock + (unsigned int) blockCount;
		else
			endBlock = BLOCKS_PER_XTS_DATA_UNIT;

		whiteningValuesPtr64 = finalInt64WhiteningValuesPtr;
		whiteningValuePtr64 = (unsigned __int64 *) whiteningValue;

		// Encrypt the data unit number using the secondary key (in order to generate the first
		// whitening value for this data unit)
		*whiteningValuePtr64 = *((unsigned __int64 *) byteBufUnitNo);
		*(whiteningValuePtr64 + 1) = 0;
		EncipherBlock (cipher, whiteningValue, ks2);

		// Generate subsequent whitening values for blocks in this data unit. Note that all generated 128-bit
		// whitening values are stored in memory as a sequence of 64-bit integers in reverse order.
		for (block = 0; block < endBlock; block++)
		{
			if (block >= startBlock)
			{
				*whiteningValuesPtr64-- = *whiteningValuePtr64++;
				*whiteningValuesPtr64-- = *whiteningValuePtr64;
			}
			else
				whiteningValuePtr64++;

			// Derive the next whitening value

#if BYTE_ORDER == LITTLE_ENDIAN

			// Little-endian platforms

			finalCarry =
				(*whiteningValuePtr64 & 0x8000000000000000) ?
				135 : 0;

			*whiteningValuePtr64-- <<= 1;

			if (*whiteningValuePtr64 & 0x8000000000000000)
				*(whiteningValuePtr64 + 1) |= 1;

			*whiteningValuePtr64 <<= 1;
#else

			// Big-endian platforms

			finalCarry =
				(*whiteningValuePtr64 & 0x80) ?
				135 : 0;

			*whiteningValuePtr64 = LE64 (LE64 (*whiteningValuePtr64) << 1);

			whiteningValuePtr64--;

			if (*whiteningValuePtr64 & 0x80)
				*(whiteningValuePtr64 + 1) |= 0x0100000000000000;

			*whiteningValuePtr64 = LE64 (LE64 (*whiteningValuePtr64) << 1);
#endif

			whiteningValue[0] ^= finalCarry;
		}

		dataUnitBufPtr = bufPtr;
		whiteningValuesPtr64 = finalInt64WhiteningValuesPtr;

		// Encrypt all blocks in this data unit

		for (block = startBlock; block < endBlock; block++)
		{
			// Pre-whitening
			*bufPtr++ ^= *whiteningValuesPtr64--;
			*bufPtr++ ^= *whiteningValuesPtr64--;
		}

		// Actual encryption
		EncipherBlocks (cipher, dataUnitBufPtr, ks, endBlock - startBlock);

		bufPtr = dataUnitBufPtr;
		whiteningValuesPtr64 = finalInt64WhiteningValuesPtr;

		for (block = startBlock; block < endBlock; block++)
		{
			// Post-whitening
			*bufPtr++ ^= *whiteningValuesPtr64--;
			*bufPtr++ ^= *whiteningValuesPtr64--;
		}

		blockCount -= endBlock - startBlock;
		startBlock = 0;
		dataUnitNo++;
		*((unsigned __int64 *) byteBufUnitNo) = LE64 (dataUnitNo);
	}

	FAST_ERASE64 (whiteningValue, sizeof (whiteningValue));
	FAST_ERASE64 (whiteningValues, sizeof (whiteningValues));
}


// Optimized for encryption algorithms not supporting intra-data-unit parallelization
static void EncryptBufferXTSNonParallel (unsigned __int8 *buffer,
					   TC_LARGEST_COMPILER_UINT length,
					   const UINT64_STRUCT *startDataUnitNo,
					   unsigned int startCipherBlockNo,
					   unsigned __int8 *ks,
					   unsigned __int8 *ks2,
					   int cipher)
{
	unsigned __int8 finalCarry;
	CRYPTOPP_ALIGN_DATA(16) unsigned __int8 whiteningValue [BYTES_PER_XTS_BLOCK];
	unsigned __int8 byteBufUnitNo [BYTES_PER_XTS_BLOCK];
	unsigned __int64 *whiteningValuePtr64 = (unsigned __int64 *) whiteningValue;
	unsigned __int64 *bufPtr = (unsigned __int64 *) buffer;
	unsigned int startBlock = startCipherBlockNo, endBlock, block;
	TC_LARGEST_COMPILER_UINT blockCount, dataUnitNo;

	/* The encrypted data unit number (i.e. the resultant ciphertext block) is to be multiplied in the
	finite field GF(2^128) by j-th power of n, where j is the sequential plaintext/ciphertext block
	number and n is 2, a primitive element of GF(2^128). This can be (and is) simplified and implemented
	as a left shift of the preceding whitening value by one bit (with carry propagating). In addition, if
	the shift of the highest byte results in a carry, 135 is XORed into the lowest byte. The value 135 is
	derived from the modulus of the Galois Field (x^128+x^7+x^2+x+1). */

	// Convert the 64-bit data unit number into a little-endian 16-byte array.
	// Note that as we are converting a 64-bit number into a 16-byte array we can always zero the last 8 bytes.
	dataUnitNo = startDataUnitNo->Value;
	*((unsigned __int64 *) byteBufUnitNo) = LE64 (dataUnitNo);
	*((unsigned __int64 *) byteBufUnitNo + 1) = 0;

	if (length % BYTES_PER_XTS_BLOCK)
		TC_THROW_FATAL_EXCEPTION;

	blockCount = length / BYTES_PER_XTS_BLOCK;

	// Process all blocks in the buffer
	while (blockCount > 0)
	{
		if (blockCount < BLOCKS_PER_XTS_DATA_UNIT)
			endBlock = startBlock + (unsigned int) blockCount;
		else
			endBlock = BLOCKS_PER_XTS_DATA_UNIT;

		whiteningValuePtr64 = (unsigned __int64 *) whiteningValue;

		// Encrypt the data unit number using the secondary key (in order to generate the first
		// whitening value for this data unit)
		*whiteningValuePtr64 = *((unsigned __int64 *) byteBufUnitNo);
		*(whiteningValuePtr64 + 1) = 0;
		EncipherBlock (cipher, whiteningValue, ks2);

		// Generate (and apply) subsequent whitening values for blocks in this data unit and
		// encrypt all relevant blocks in this data unit
		for (block = 0; block < endBlock; block++)
		{
			if (block >= startBlock)
			{
				// Pre-whitening
				*bufPtr++ ^= *whiteningValuePtr64++;
				*bufPtr-- ^= *whiteningValuePtr64--;

				// Actual encryption
				EncipherBlock (cipher, bufPtr, ks);

				// Post-whitening
				*bufPtr++ ^= *whiteningValuePtr64++;
				*bufPtr++ ^= *whiteningValuePtr64;
			}
			else
				whiteningValuePtr64++;

			// Derive the next whitening value

#if BYTE_ORDER == LITTLE_ENDIAN

			// Little-endian platforms

			finalCarry =
				(*whiteningValuePtr64 & 0x8000000000000000) ?
				135 : 0;

			*whiteningValuePtr64-- <<= 1;

			if (*whiteningValuePtr64 & 0x8000000000000000)
				*(whiteningValuePtr64 + 1) |= 1;

			*whiteningValuePtr64 <<= 1;
#else

			// Big-endian platforms

			finalCarry =
				(*whiteningValuePtr64 & 0x80) ?
				135 : 0;

			*whiteningValuePtr64 = LE64 (LE64 (*whiteningValuePtr64) << 1);

			whiteningValuePtr64--;

			if (*whiteningValuePtr64 & 0x80)
				*(whiteningValuePtr64 + 1) |= 0x0100000000000000;

			*whiteningValuePtr64 = LE64 (LE64 (*whiteningValuePtr64) << 1);
#endif

			whiteningValue[0] ^= finalCarry;
		}

		blockCount -= endBlock - startBlock;
		startBlock = 0;
		dataUnitNo++;
		*((unsigned __int64 *) byteBufUnitNo) = LE64 (dataUnitNo);
	}

	FAST_ERASE64 (whiteningValue, sizeof (whiteningValue));
}


// For descriptions of the input parameters, see EncryptBufferXTS().
void DecryptBufferXTS (unsigned __int8 *buffer,
					   TC_LARGEST_COMPILER_UINT length,
					   const UINT64_STRUCT *startDataUnitNo,
					   unsigned int startCipherBlockNo,
					   unsigned __int8 *ks,
					   unsigned __int8 *ks2,
					   int cipher)
{
	if (CipherSupportsIntraDataUnitParallelization (cipher))
		DecryptBufferXTSParallel (buffer, length, startDataUnitNo, startCipherBlockNo, ks, ks2, cipher);
	else
		DecryptBufferXTSNonParallel (buffer, length, startDataUnitNo, startCipherBlockNo, ks, ks2, cipher);
}


// Optimized for encryption algorithms supporting intra-data-unit parallelization
static void DecryptBufferXTSParallel (unsigned __int8 *buffer,
					   TC_LARGEST_COMPILER_UINT length,
					   const UINT64_STRUCT *startDataUnitNo,
					   unsigned int startCipherBlockNo,
					   unsigned __int8 *ks,
					   unsigned __int8 *ks2,
					   int cipher)
{
	unsigned __int8 finalCarry;
	unsigned __int8 whiteningValues [ENCRYPTION_DATA_UNIT_SIZE];
	unsigned __int8 whiteningValue [BYTES_PER_XTS_BLOCK];
	unsigned __int8 byteBufUnitNo [BYTES_PER_XTS_BLOCK];
	unsigned __int64 *whiteningValuesPtr64 = (unsigned __int64 *) whiteningValues;
	unsigned __int64 *whiteningValuePtr64 = (unsigned __int64 *) whiteningValue;
	unsigned __int64 *bufPtr = (unsigned __int64 *) buffer;
	unsigned __int64 *dataUnitBufPtr;
	unsigned int startBlock = startCipherBlockNo, endBlock, block;
	unsigned __int64 *const finalInt64WhiteningValuesPtr = whiteningValuesPtr64 + sizeof (whiteningValues) / sizeof (*whiteningValuesPtr64) - 1;
	TC_LARGEST_COMPILER_UINT blockCount, dataUnitNo;

	// Convert the 64-bit data unit number into a little-endian 16-byte array.
	// Note that as we are converting a 64-bit number into a 16-byte array we can always zero the last 8 bytes.
	dataUnitNo = startDataUnitNo->Value;
	*((unsigned __int64 *) byteBufUnitNo) = LE64 (dataUnitNo);
	*((unsigned __int64 *) byteBufUnitNo + 1) = 0;

	if (length % BYTES_PER_XTS_BLOCK)
		TC_THROW_FATAL_EXCEPTION;

	blockCount = length / BYTES_PER_XTS_BLOCK;

	// Process all blocks in the buffer
	while (blockCount > 0)
	{
		if (blockCount < BLOCKS_PER_XTS_DATA_UNIT)
			endBlock = startBlock + (unsigned int) blockCount;
		else
			endBlock = BLOCKS_PER_XTS_DATA_UNIT;

		whiteningValuesPtr64 = finalInt64WhiteningValuesPtr;
		whiteningValuePtr64 = (unsigned __int64 *) whiteningValue;

		// Encrypt the data unit number using the secondary key (in order to generate the first
		// whitening value for this data unit)
		*whiteningValuePtr64 = *((unsigned __int64 *) byteBufUnitNo);
		*(whiteningValuePtr64 + 1) = 0;
		EncipherBlock (cipher, whiteningValue, ks2);

		// Generate subsequent whitening values for blocks in this data unit. Note that all generated 128-bit
		// whitening values are stored in memory as a sequence of 64-bit integers in reverse order.
		for (block = 0; block < endBlock; block++)
		{
			if (block >= startBlock)
			{
				*whiteningValuesPtr64-- = *whiteningValuePtr64++;
				*whiteningValuesPtr64-- = *whiteningValuePtr64;
			}
			else
				whiteningValuePtr64++;

			// Derive the next whitening value

#if BYTE_ORDER == LITTLE_ENDIAN

			// Little-endian platforms

			finalCarry =
				(*whiteningValuePtr64 & 0x8000000000000000) ?
				135 : 0;

			*whiteningValuePtr64-- <<= 1;

			if (*whiteningValuePtr64 & 0x8000000000000000)
				*(whiteningValuePtr64 + 1) |= 1;

			*whiteningValuePtr64 <<= 1;

#else
			// Big-endian platforms

			finalCarry =
				(*whiteningValuePtr64 & 0x80) ?
				135 : 0;

			*whiteningValuePtr64 = LE64 (LE64 (*whiteningValuePtr64) << 1);

			whiteningValuePtr64--;

			if (*whiteningValuePtr64 & 0x80)
				*(whiteningValuePtr64 + 1) |= 0x0100000000000000;

			*whiteningValuePtr64 = LE64 (LE64 (*whiteningValuePtr64) << 1);
#endif

			whiteningValue[0] ^= finalCarry;
		}

		dataUnitBufPtr = bufPtr;
		whiteningValuesPtr64 = finalInt64WhiteningValuesPtr;

		// Decrypt blocks in this data unit

		for (block = startBlock; block < endBlock; block++)
		{
			*bufPtr++ ^= *whiteningValuesPtr64--;
			*bufPtr++ ^= *whiteningValuesPtr64--;
		}

		DecipherBlocks (cipher, dataUnitBufPtr, ks, endBlock - startBlock);

		bufPtr = dataUnitBufPtr;
		whiteningValuesPtr64 = finalInt64WhiteningValuesPtr;

		for (block = startBlock; block < endBlock; block++)
		{
			*bufPtr++ ^= *whiteningValuesPtr64--;
			*bufPtr++ ^= *whiteningValuesPtr64--;
		}

		blockCount -= endBlock - startBlock;
		startBlock = 0;
		dataUnitNo++;

		*((unsigned __int64 *) byteBufUnitNo) = LE64 (dataUnitNo);
	}

	FAST_ERASE64 (whiteningValue, sizeof (whiteningValue));
	FAST_ERASE64 (whiteningValues, sizeof (whiteningValues));
}


// Optimized for encryption algorithms not supporting intra-data-unit parallelization
static void DecryptBufferXTSNonParallel (unsigned __int8 *buffer,
					   TC_LARGEST_COMPILER_UINT length,
					   const UINT64_STRUCT *startDataUnitNo,
					   unsigned int startCipherBlockNo,
					   unsigned __int8 *ks,
					   unsigned __int8 *ks2,
					   int cipher)
{
	unsigned __int8 finalCarry;
	unsigned __int8 whiteningValue [BYTES_PER_XTS_BLOCK];
	unsigned __int8 byteBufUnitNo [BYTES_PER_XTS_BLOCK];
	unsigned __int64 *whiteningValuePtr64 = (unsigned __int64 *) whiteningValue;
	unsigned __int64 *bufPtr = (unsigned __int64 *) buffer;
	unsigned int startBlock = startCipherBlockNo, endBlock, block;
	TC_LARGEST_COMPILER_UINT blockCount, dataUnitNo;

	// Convert the 64-bit data unit number into a little-endian 16-byte array.
	// Note that as we are converting a 64-bit number into a 16-byte array we can always zero the last 8 bytes.
	dataUnitNo = startDataUnitNo->Value;
	*((unsigned __int64 *) byteBufUnitNo) = LE64 (dataUnitNo);
	*((unsigned __int64 *) byteBufUnitNo + 1) = 0;

	if (length % BYTES_PER_XTS_BLOCK)
		TC_THROW_FATAL_EXCEPTION;

	blockCount = length / BYTES_PER_XTS_BLOCK;

	// Process all blocks in the buffer
	while (blockCount > 0)
	{
		if (blockCount < BLOCKS_PER_XTS_DATA_UNIT)
			endBlock = startBlock + (unsigned int) blockCount;
		else
			endBlock = BLOCKS_PER_XTS_DATA_UNIT;

		whiteningValuePtr64 = (unsigned __int64 *) whiteningValue;

		// Encrypt the data unit number using the secondary key (in order to generate the first
		// whitening value for this data unit)
		*whiteningValuePtr64 = *((unsigned __int64 *) byteBufUnitNo);
		*(whiteningValuePtr64 + 1) = 0;
		EncipherBlock (cipher, whiteningValue, ks2);

		// Generate (and apply) subsequent whitening values for blocks in this data unit and
		// decrypt all relevant blocks in this data unit
		for (block = 0; block < endBlock; block++)
		{
			if (block >= startBlock)
			{
				// Post-whitening
				*bufPtr++ ^= *whiteningValuePtr64++;
				*bufPtr-- ^= *whiteningValuePtr64--;

				// Actual decryption
				DecipherBlock (cipher, bufPtr, ks);

				// Pre-whitening
				*bufPtr++ ^= *whiteningValuePtr64++;
				*bufPtr++ ^= *whiteningValuePtr64;
			}
			else
				whiteningValuePtr64++;

			// Derive the next whitening value

#if BYTE_ORDER == LITTLE_ENDIAN

			// Little-endian platforms

			finalCarry =
				(*whiteningValuePtr64 & 0x8000000000000000) ?
				135 : 0;

			*whiteningValuePtr64-- <<= 1;

			if (*whiteningValuePtr64 & 0x8000000000000000)
				*(whiteningValuePtr64 + 1) |= 1;

			*whiteningValuePtr64 <<= 1;

#else
			// Big-endian platforms

			finalCarry =
				(*whiteningValuePtr64 & 0x80) ?
				135 : 0;

			*whiteningValuePtr64 = LE64 (LE64 (*whiteningValuePtr64) << 1);

			whiteningValuePtr64--;

			if (*whiteningValuePtr64 & 0x80)
				*(whiteningValuePtr64 + 1) |= 0x0100000000000000;

			*whiteningValuePtr64 = LE64 (LE64 (*whiteningValuePtr64) << 1);
#endif

			whiteningValue[0] ^= finalCarry;
		}

		blockCount -= endBlock - startBlock;
		startBlock = 0;
		dataUnitNo++;
		*((unsigned __int64 *) byteBufUnitNo) = LE64 (dataUnitNo);
	}

	FAST_ERASE64 (whiteningValue, sizeof (whiteningValue));
}


#else	// TC_NO_COMPILER_INT64

/* ---- The following code is to be used only when native 64-bit data types are not available. ---- */

#if BYTE_ORDER == BIG_ENDIAN
#error The TC_NO_COMPILER_INT64 version of the XTS code is not compatible with big-endian platforms
#endif


// Converts a 64-bit unsigned integer (passed as two 32-bit integers for compatibility with non-64-bit
// environments/platforms) into a little-endian 16-byte array.
static void Uint64ToLE16ByteArray (unsigned __int8 *byteBuf, unsigned __int32 highInt32, unsigned __int32 lowInt32)
{
	unsigned __int32 *bufPtr32 = (unsigned __int32 *) byteBuf;

	*bufPtr32++ = lowInt32;
	*bufPtr32++ = highInt32;

	// We're converting a 64-bit number into a little-endian 16-byte array so we can zero the last 8 bytes
	*bufPtr32++ = 0;
	*bufPtr32 = 0;
}


// Encrypts or decrypts all blocks in the buffer in XTS mode. For descriptions of the input parameters,
// see the 64-bit version of EncryptBufferXTS().
static void EncryptDecryptBufferXTS32 (const unsigned __int8 *buffer,
							TC_LARGEST_COMPILER_UINT length,
							const UINT64_STRUCT *startDataUnitNo,
							unsigned int startBlock,
							unsigned __int8 *ks,
							unsigned __int8 *ks2,
							int cipher,
							BOOL decryption)
{
	TC_LARGEST_COMPILER_UINT blockCount;
	UINT64_STRUCT dataUnitNo;
	unsigned int block;
	unsigned int endBlock;
	unsigned __int8 byteBufUnitNo [BYTES_PER_XTS_BLOCK];
	unsigned __int8 whiteningValue [BYTES_PER_XTS_BLOCK];
	unsigned __int32 *bufPtr32 = (unsigned __int32 *) buffer;
	unsigned __int32 *whiteningValuePtr32 = (unsigned __int32 *) whiteningValue;
	unsigned __int8 finalCarry;
	unsigned __int32 *const finalDwordWhiteningValuePtr = whiteningValuePtr32 + sizeof (whiteningValue) / sizeof (*whiteningValuePtr32) - 1;

	// Store the 64-bit data unit number in a way compatible with non-64-bit environments/platforms
	dataUnitNo.HighPart = startDataUnitNo->HighPart;
	dataUnitNo.LowPart = startDataUnitNo->LowPart;

	blockCount = length / BYTES_PER_XTS_BLOCK;

	// Convert the 64-bit data unit number into a little-endian 16-byte array.
	// (Passed as two 32-bit integers for compatibility with non-64-bit environments/platforms.)
	Uint64ToLE16ByteArray (byteBufUnitNo, dataUnitNo.HighPart, dataUnitNo.LowPart);

	// Generate whitening values for all blocks in the buffer
	while (blockCount > 0)
	{
		if (blockCount < BLOCKS_PER_XTS_DATA_UNIT)
			endBlock = startBlock + (unsigned int) blockCount;
		else
			endBlock = BLOCKS_PER_XTS_DATA_UNIT;

		// Encrypt the data unit number using the secondary key (in order to generate the first
		// whitening value for this data unit)
		memcpy (whiteningValue, byteBufUnitNo, BYTES_PER_XTS_BLOCK);
		EncipherBlock (cipher, whiteningValue, ks2);

		// Generate (and apply) subsequent whitening values for blocks in this data unit and
		// encrypt/decrypt all relevant blocks in this data unit
		for (block = 0; block < endBlock; block++)
		{
			if (block >= startBlock)
			{
				whiteningValuePtr32 = (unsigned __int32 *) whiteningValue;

				// Whitening
				*bufPtr32++ ^= *whiteningValuePtr32++;
				*bufPtr32++ ^= *whiteningValuePtr32++;
				*bufPtr32++ ^= *whiteningValuePtr32++;
				*bufPtr32 ^= *whiteningValuePtr32;

				bufPtr32 -= BYTES_PER_XTS_BLOCK / sizeof (*bufPtr32) - 1;

				// Actual encryption/decryption
				if (decryption)
					DecipherBlock (cipher, bufPtr32, ks);
				else
					EncipherBlock (cipher, bufPtr32, ks);

				whiteningValuePtr32 = (unsigned __int32 *) whiteningValue;

				// Whitening
				*bufPtr32++ ^= *whiteningValuePtr32++;
				*bufPtr32++ ^= *whiteningValuePtr32++;
				*bufPtr32++ ^= *whiteningValuePtr32++;
				*bufPtr32++ ^= *whiteningValuePtr32;
			}

			// Derive the next whitening value

			finalCarry = 0;

			for (whiteningValuePtr32 = finalDwordWhiteningValuePtr;
				whiteningValuePtr32 >= (unsigned __int32 *) whiteningValue;
				whiteningValuePtr32--)
			{
				if (*whiteningValuePtr32 & 0x80000000)	// If the following shift results in a carry
				{
					if (whiteningValuePtr32 != finalDwordWhiteningValuePtr)	// If not processing the highest double word
					{
						// A regular carry
						*(whiteningValuePtr32 + 1) |= 1;
					}
					else
					{
						// The highest byte shift will result in a carry
						finalCarry = 135;
					}
				}

				*whiteningValuePtr32 <<= 1;
			}

			whiteningValue[0] ^= finalCarry;
		}

		blockCount -= endBlock - startBlock;
		startBlock = 0;

		// Increase the data unit number by one
		if (!++dataUnitNo.LowPart)
		{
			dataUnitNo.HighPart++;
		}

		// Convert the 64-bit data unit number into a little-endian 16-byte array.
		Uint64ToLE16ByteArray (byteBufUnitNo, dataUnitNo.HighPart, dataUnitNo.LowPart);
	}

	FAST_ERASE64 (whiteningValue, sizeof (whiteningValue));
}


// For descriptions of the input parameters, see the 64-bit version of EncryptBufferXTS() above.
void EncryptBufferXTS (unsigned __int8 *buffer,
					   TC_LARGEST_COMPILER_UINT length,
					   const UINT64_STRUCT *startDataUnitNo,
					   unsigned int startCipherBlockNo,
					   unsigned __int8 *ks,
					   unsigned __int8 *ks2,
					   int cipher)
{
	// Encrypt all plaintext blocks in the buffer
	EncryptDecryptBufferXTS32 (buffer, length, startDataUnitNo, startCipherBlockNo, ks, ks2, cipher, FALSE);
}


// For descriptions of the input parameters, see the 64-bit version of EncryptBufferXTS().
void DecryptBufferXTS (unsigned __int8 *buffer,
					   TC_LARGEST_COMPILER_UINT length,
					   const UINT64_STRUCT *startDataUnitNo,
					   unsigned int startCipherBlockNo,
					   unsigned __int8 *ks,
					   unsigned __int8 *ks2,
					   int cipher)
{
	// Decrypt all ciphertext blocks in the buffer
	EncryptDecryptBufferXTS32 (buffer, length, startDataUnitNo, startCipherBlockNo, ks, ks2, cipher, TRUE);
}

#endif	// TC_NO_COMPILER_INT64