/*
 * File:	RijndaelCBCMAC.h
 *
 * Copyright (c) Freescale Semiconductor, Inc. All rights reserved.
 * See included license file for license details.
 */
#if !defined(_RijndaelCBCMAC_h_)
#define _RijndaelCBCMAC_h_

#include "AESKey.h"
#include <string.h>

/*!
 * \brief Class to compute CBC-MAC using the AES/Rijndael cipher.
 *
 * Currently only supports 128-bit keys and block sizes.
 */
class RijndaelCBCMAC
{
public:
    enum
    {
        BLOCK_SIZE = 16 //!< Number of bytes in one cipher block.
    };

    //! The cipher block data type.
    typedef uint8_t block_t[BLOCK_SIZE];

public:
    //! \brief Default constructor.
    //!
    //! The key and IV are both set to zero.
    RijndaelCBCMAC() {}
    //! \brief Constructor.
    RijndaelCBCMAC(const AESKey<128> &key, const uint8_t *iv = 0);

    //! \brief Process data.
    void update(const uint8_t *data, unsigned length);

    //! \brief Signal that all data has been processed.
    void finalize();

    //! \brief Returns a reference to the current MAC value.
    const block_t &getMAC() const { return m_mac; }
    //! \brief Assignment operator.
    RijndaelCBCMAC &operator=(const RijndaelCBCMAC &other)
    {
        m_key = other.m_key;
        memcpy(m_mac, other.m_mac, sizeof(m_mac));
        return *this;
    }

protected:
    AESKey<128> m_key; //!< 128-bit key to use for the CBC-MAC.
    block_t m_mac;     //!< Current message authentication code value.

    void updateOneBlock(const uint8_t *data);
};

#endif // _RijndaelCBCMAC_h_