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//*****************************************************************************
//
// aes256.c - Driver for the aes256 Module.
//
//*****************************************************************************

//*****************************************************************************
//
//! \addtogroup aes256_api aes256
//! @{
//
//*****************************************************************************

#include "inc/hw_memmap.h"

#ifdef __MSP430_HAS_AES256__
#include "aes256.h"

#include <assert.h>

uint8_t AES256_setCipherKey (uint16_t baseAddress,
	const uint8_t * cipherKey,
	uint16_t keyLength)
{
	uint8_t i;
	uint16_t sCipherKey;

	HWREG16(baseAddress + OFS_AESACTL0) &= (~(AESKL_1 + AESKL_2));

	switch(keyLength)
	{
		case AES256_KEYLENGTH_128BIT :
			HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__128;
			break;

		case AES256_KEYLENGTH_192BIT :
			HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__192;
			break;

		case AES256_KEYLENGTH_256BIT :
			HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__256;
			break;

		default :
			return STATUS_FAIL;
		}

		keyLength = keyLength / 8;

		for (i = 0; i < keyLength; i = i + 2)
		{
			sCipherKey = (uint16_t)(cipherKey[i]);
			sCipherKey = sCipherKey | ((uint16_t)(cipherKey[i + 1]) << 8);
			HWREG16(baseAddress + OFS_AESAKEY) = sCipherKey;
		}

	    // Wait until key is written
            while(0x00 == (HWREG16(baseAddress + OFS_AESASTAT) & AESKEYWR ));
	    return STATUS_SUCCESS;
}

void AES256_encryptData (uint16_t baseAddress,
	const uint8_t * data,
	uint8_t * encryptedData)
{
	uint8_t i;
	uint16_t tempData = 0;
	uint16_t tempVariable = 0;

	// Set module to encrypt mode
	HWREG16(baseAddress + OFS_AESACTL0) &= ~AESOP_3;


	// Write data to encrypt to module
	for (i = 0; i < 16; i = i + 2)
	{
		tempVariable = (uint16_t)(data[i]);
		tempVariable = tempVariable | ((uint16_t)(data[i+1]) << 8);
		HWREG16(baseAddress + OFS_AESADIN) = tempVariable;
	}

	// Key that is already written shall be used
	// Encryption is initialized by setting AESKEYWR to 1
	HWREG16(baseAddress + OFS_AESASTAT) |= AESKEYWR;

	// Wait unit finished ~167 MCLK
	while(AESBUSY == (HWREG16(baseAddress + OFS_AESASTAT) & AESBUSY) );

	// Write encrypted data back to variable
	for (i = 0; i < 16; i = i + 2)
	{
		tempData = HWREG16(baseAddress + OFS_AESADOUT);
		*(encryptedData + i) = (uint8_t)tempData;
		*(encryptedData +i + 1) = (uint8_t)(tempData >> 8);


	}
}

void AES256_decryptData (uint16_t baseAddress,
	const uint8_t * data,
	uint8_t * decryptedData)
{
	uint8_t i;
	uint16_t tempData = 0;
	uint16_t tempVariable = 0;

	// Set module to decrypt mode
	HWREG16(baseAddress + OFS_AESACTL0) |= (AESOP_3);

	// Write data to decrypt to module
	for (i = 0; i < 16; i = i + 2)
	{
		tempVariable = (uint16_t)(data[i+1]  << 8);
		tempVariable = tempVariable | ((uint16_t)(data[i]));
		HWREG16(baseAddress + OFS_AESADIN) = tempVariable;
	}

	// Key that is already written shall be used
	// Now decryption starts
	HWREG16(baseAddress + OFS_AESASTAT) |= AESKEYWR;

	// Wait unit finished ~167 MCLK
	while(AESBUSY == (HWREG16(baseAddress + OFS_AESASTAT) & AESBUSY ));

	// Write encrypted data back to variable
	for (i = 0; i < 16; i = i + 2)
	{
		tempData = HWREG16(baseAddress + OFS_AESADOUT);
		*(decryptedData + i) = (uint8_t)tempData;
		*(decryptedData +i + 1) = (uint8_t)(tempData >> 8);
	}
}

uint8_t AES256_setDecipherKey (uint16_t baseAddress,
	const uint8_t * cipherKey,
	uint16_t keyLength
	)
{
	uint8_t i;
	uint16_t tempVariable = 0;
	
	// Set module to decrypt mode
	HWREG16(baseAddress + OFS_AESACTL0) &= ~(AESOP0);
	HWREG16(baseAddress + OFS_AESACTL0) |= AESOP1;

	switch(keyLength)
	{
		case AES256_KEYLENGTH_128BIT :
			HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__128;
			break;

		case AES256_KEYLENGTH_192BIT :
			HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__192;
			break;

		case AES256_KEYLENGTH_256BIT :
			HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__256;
			break;

		default :
			return STATUS_FAIL;
	}


	keyLength = keyLength / 8;


	// Write cipher key to key register
	for (i = 0; i < keyLength; i = i + 2)
	{
		tempVariable = (uint16_t)(cipherKey[i]);
		tempVariable = tempVariable | ((uint16_t)(cipherKey[i + 1]) << 8);
		HWREG16(baseAddress + OFS_AESAKEY) = tempVariable;
	}

	// Wait until key is processed ~52 MCLK
	while((HWREG16(baseAddress + OFS_AESASTAT) & AESBUSY) == AESBUSY);

	return STATUS_SUCCESS;
}

void AES256_clearInterrupt (uint16_t baseAddress )
{
	HWREG16(baseAddress + OFS_AESACTL0) &=  ~AESRDYIFG;
}

uint32_t AES256_getInterruptStatus (uint16_t baseAddress)
{
    return ((HWREG16(baseAddress + OFS_AESACTL0) & AESRDYIFG) << 0x04);
}

void AES256_enableInterrupt (uint16_t baseAddress)
{
	HWREG16(baseAddress + OFS_AESACTL0) |=  AESRDYIE;
}

void AES256_disableInterrupt (uint16_t baseAddress)
{
	HWREG16(baseAddress + OFS_AESACTL0) &=  ~AESRDYIE;
}

void AES256_reset (uint16_t baseAddress)
{
	HWREG16(baseAddress + OFS_AESACTL0) |=  AESSWRST;
}

void AES256_startEncryptData (uint16_t baseAddress,
	const uint8_t * data)
{
	uint8_t i;
	uint16_t tempVariable = 0;

	// Set module to encrypt mode
	HWREG16(baseAddress + OFS_AESACTL0) &= ~AESOP_3;


	// Write data to encrypt to module
	for (i = 0; i < 16; i = i + 2)
	{
		tempVariable = (uint16_t)(data[i]);
		tempVariable = tempVariable | ((uint16_t)(data[i+1 ]) << 8);
		HWREG16(baseAddress + OFS_AESADIN) = tempVariable;
	}

	// Key that is already written shall be used
	// Encryption is initialized by setting AESKEYWR to 1
	HWREG16(baseAddress + OFS_AESASTAT) |= AESKEYWR;
}

void AES256_startDecryptData (uint16_t baseAddress,
	const uint8_t * data)
{
	uint8_t i;
	uint16_t tempVariable = 0;

	// Set module to decrypt mode
	HWREG16(baseAddress + OFS_AESACTL0) |= (AESOP_3);

	// Write data to decrypt to module
	for (i = 0; i < 16; i = i + 2)
	{
		tempVariable = (uint16_t)(data[i+1]  << 8);
		tempVariable = tempVariable | ((uint16_t)(data[i]));
		HWREG16(baseAddress + OFS_AESADIN) = tempVariable;
	}

	// Key that is already written shall be used
	// Now decryption starts
	HWREG16(baseAddress + OFS_AESASTAT) |= AESKEYWR;
}

uint8_t AES256_startSetDecipherKey (uint16_t baseAddress,
	const uint8_t * cipherKey,
	uint16_t keyLength)
{
	uint8_t i;
	uint16_t tempVariable = 0;

	HWREG16(baseAddress + OFS_AESACTL0) &= ~(AESOP0);
	HWREG16(baseAddress + OFS_AESACTL0) |= AESOP1;

	switch(keyLength)
	{
		case AES256_KEYLENGTH_128BIT :
			HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__128;
			break;

		case AES256_KEYLENGTH_192BIT :
			HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__192;
			break;

		case AES256_KEYLENGTH_256BIT :
			HWREG16(baseAddress + OFS_AESACTL0) |= AESKL__256;
			break;

		default :
			return STATUS_FAIL;
		}

	keyLength = keyLength / 8;

	// Write cipher key to key register
	for (i = 0; i < keyLength; i = i + 2)
	{
		tempVariable = (uint16_t)(cipherKey[i]);
		tempVariable = tempVariable | ((uint16_t)(cipherKey[i+1]) << 8);
		HWREG16(baseAddress + OFS_AESAKEY) = tempVariable;
	}

	return STATUS_SUCCESS;
}

uint8_t  AES256_getDataOut(uint16_t baseAddress,
							uint8_t *outputData
							)
{
	uint8_t i;
	uint16_t tempData = 0;

	// If module is busy, exit and return failure
	if( AESBUSY == (HWREG16(baseAddress + OFS_AESASTAT) & AESBUSY))
		return STATUS_FAIL;

	// Write encrypted data back to variable
	for (i = 0; i < 16; i = i + 2)
	{
		tempData = HWREG16(baseAddress + OFS_AESADOUT);
		*(outputData + i ) = (uint8_t)tempData;
		*(outputData +i + 1) = (uint8_t)(tempData >> 8);
	}

	return STATUS_SUCCESS;
}

uint16_t AES256_isBusy (uint16_t baseAddress)
{
    return (HWREG16(baseAddress + OFS_AESASTAT) & AESBUSY);
}

void AES256_clearErrorFlag (uint16_t baseAddress )
{
	HWREG16(baseAddress + OFS_AESACTL0) &=  ~AESERRFG;
}

uint32_t AES256_getErrorFlagStatus (uint16_t baseAddress)
{
    return (HWREG16(baseAddress + OFS_AESACTL0) & AESERRFG);
}

#endif
//*****************************************************************************
//
//! Close the doxygen group for aes256_api
//! @}
//
//*****************************************************************************