/* --COPYRIGHT--,BSD
 * Copyright (c) 2017, Texas Instruments Incorporated
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * *  Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * *  Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * *  Neither the name of Texas Instruments Incorporated nor the names of
 *    its contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * --/COPYRIGHT--*/
//*****************************************************************************
//
// aes.c - Driver for the aes Module.
//
//*****************************************************************************

//*****************************************************************************
//
//! \addtogroup aes_api aes
//! @{
//
//*****************************************************************************

#include "inc/hw_memmap.h"

#ifdef __MSP430_HAS_AES__
#include "aes.h"

#include <assert.h>

uint8_t AES_setCipherKey (uint16_t baseAddress,
     const uint8_t * CipherKey
     )
{
    uint8_t i = 0;
    uint16_t tempVariable = 0;

    // Wait until AES accelerator is busy
    while(AESBUSY == (HWREG16(baseAddress + OFS_AESASTAT) & AESBUSY) );

    for (i = 0; i < 16; 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 written
    while(0x00 == (HWREG16(baseAddress + OFS_AESASTAT) & AESKEYWR ));

    return STATUS_SUCCESS;
}

uint8_t AES_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);

    }

    return STATUS_SUCCESS;
}

uint8_t AES_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);
    }

    return STATUS_SUCCESS;
}

uint8_t AES_setDecipherKey (uint16_t baseAddress,
    const uint8_t * CipherKey)
{
    uint8_t i;
    uint16_t tempVariable = 0;

    // Set module to decrypt mode
    HWREG16(baseAddress + OFS_AESACTL0) &= ~(AESOP0);
    HWREG16(baseAddress + OFS_AESACTL0) |= AESOP1;

    // Write cipher key to key register
    for (i = 0; i < 16; 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 AES_clearInterrupt (uint16_t baseAddress )
{
    HWREG8(baseAddress + OFS_AESACTL0) &=  ~AESRDYIFG;
}

uint32_t AES_getInterruptStatus (uint16_t baseAddress)
{
    return ((HWREG8(baseAddress + OFS_AESACTL0) & AESRDYIFG) << 0x04);
}

void AES_enableInterrupt (uint16_t baseAddress)
{
    HWREG8(baseAddress + OFS_AESACTL0) |=  AESRDYIE;
}

void AES_disableInterrupt (uint16_t baseAddress)
{
    HWREG8(baseAddress + OFS_AESACTL0) &=  ~AESRDYIE;
}

void AES_reset (uint16_t baseAddress)
{
    HWREG8(baseAddress + OFS_AESACTL0) |=  AESSWRST;
}

uint8_t AES_startEncryptData (uint16_t baseAddress,
    const uint8_t * Data,
    uint8_t * encryptedData)
{
    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;

    return STATUS_SUCCESS;
}

uint8_t AES_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;

    return STATUS_SUCCESS;
}

uint8_t AES_startSetDecipherKey (uint16_t baseAddress,
    const uint8_t * CipherKey)
{
    uint8_t i;
    uint16_t tempVariable = 0;

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

    // Write cipher key to key register
    for (i = 0; i < 16; 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  AES_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;
}

uint8_t AES_isBusy (uint16_t baseAddress)
{
    return (HWREG16(baseAddress + OFS_AESASTAT) & AESBUSY);
}

void AES_clearErrorFlag (uint16_t baseAddress )
{
    HWREG8(baseAddress + OFS_AESACTL0) &=  ~AESERRFG;
}

uint32_t AES_getErrorFlagStatus (uint16_t baseAddress)
{
    return (HWREG8(baseAddress + OFS_AESACTL0) & AESERRFG);
}

uint8_t AES_startDecryptDataUsingEncryptionKey (
    uint16_t baseAddress,
    const uint8_t * Data)
{
    uint8_t i;
    uint16_t tempVariable = 0;

    // Set module to decrypt mode
    HWREG16(baseAddress + OFS_AESACTL0) &= ~(AESOP1);
    HWREG16(baseAddress + OFS_AESACTL0) |= AESOP0;

    // 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;

    return STATUS_SUCCESS;
}

uint8_t AES_decryptDataUsingEncryptionKey (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) &= ~(AESOP1);
    HWREG16(baseAddress + OFS_AESACTL0) |= AESOP0;

    // 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 ~214 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);
    }

    return STATUS_SUCCESS;
}

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