// cham.h - written and placed in the public domain by Kim Sung Hee and Jeffrey Walton

//          Based on "CHAM: A Family of Lightweight Block Ciphers for

//          Resource-Constrained Devices" by Bonwook Koo, Dongyoung Roh,

//          Hyeonjin Kim, Younghoon Jung, Dong-Geon Lee, and Daesung Kwon

/// \file cham.h

/// \brief Classes for the CHAM block cipher

/// \since Crypto++ 8.0

#ifndef CRYPTOPP_CHAM_H

#define CRYPTOPP_CHAM_H

#include "config.h"

#include "seckey.h"

#include "secblock.h"

#include "algparam.h"

#if (CRYPTOPP_BOOL_X64 || CRYPTOPP_BOOL_X32 || CRYPTOPP_BOOL_X86)

# define CRYPTOPP_CHAM128_ADVANCED_PROCESS_BLOCKS 1

#endif

// Yet another SunStudio/SunCC workaround. Failed self tests

// in SSE code paths on i386 for SunStudio 12.3 and below.

#if defined(__SUNPRO_CC) && (__SUNPRO_CC <= 0x5120)

# undef CRYPTOPP_CHAM128_ADVANCED_PROCESS_BLOCKS

#endif

NAMESPACE_BEGIN(CryptoPP)

/// \brief CHAM block cipher information

/// \since Crypto++ 8.0

struct CHAM64_Info : public FixedBlockSize<8>, public FixedKeyLength<16>

{

    /// \brief The algorithm name

    /// \return the algorithm name

    /// \details StaticAlgorithmName returns the algorithm's name as a static

    ///   member function.

    static const std::string StaticAlgorithmName()

    {

        // Format is Cipher-Blocksize

        return "CHAM-64";

    }

};

/// \brief CHAM block cipher information

/// \since Crypto++ 8.0

struct CHAM128_Info : public FixedBlockSize<16>, public VariableKeyLength<16,16,32,16>

{

    /// \brief The algorithm name

    /// \return the algorithm name

    /// \details StaticAlgorithmName returns the algorithm's name as a static

    ///   member function.

    static const std::string StaticAlgorithmName()

    {

        // Format is Cipher-Blocksize

        return "CHAM-128";

    }

};

/// \brief CHAM 64-bit block cipher

/// \details CHAM64 provides 64-bit block size. The valid key size is 128-bit.

/// \note Crypto++ provides a byte oriented implementation

/// \sa CHAM128, <a href="http://www.cryptopp.com/wiki/CHAM">CHAM</a>,

///   <a href="https://pdfs.semanticscholar.org/2f57/61b5c2614cffd58a09cc83c375a2b32a2ed3.pdf">

///   CHAM: A Family of Lightweight Block Ciphers for Resource-Constrained Devices</a>

/// \since Crypto++ 8.0

class CRYPTOPP_NO_VTABLE CHAM64 : public CHAM64_Info, public BlockCipherDocumentation

{

public:

    /// \brief CHAM block cipher transformation functions

    /// \details Provides implementation common to encryption and decryption

    /// \since Crypto++ 8.0

    class CRYPTOPP_NO_VTABLE Base : public BlockCipherImpl<CHAM64_Info>

    {

    protected:

        void UncheckedSetKey(const byte *userKey, unsigned int keyLength, const NameValuePairs &params);

        SecBlock<word16> m_rk;

        mutable FixedSizeSecBlock<word16, 4> m_x;

        unsigned int m_kw;

    };

    /// \brief Encryption transformation

    /// \details Enc provides implementation for encryption transformation. All key and block

    ///   sizes are supported.

    /// \since Crypto++ 8.0

    class CRYPTOPP_NO_VTABLE Enc : public Base

    {

    public:

        void ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const;

    };

    /// \brief Decryption transformation

    /// \details Dec provides implementation for decryption transformation. All key and block

    ///   sizes are supported.

    /// \since Crypto++ 8.0

    class CRYPTOPP_NO_VTABLE Dec : public Base

    {

    public:

        void ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const;

    };

    /// \brief CHAM64 encryption

    typedef BlockCipherFinal<ENCRYPTION, Enc> Encryption;

    /// \brief CHAM64 decryption

    typedef BlockCipherFinal<DECRYPTION, Dec> Decryption;

};

/// \brief CHAM64 encryption

typedef CHAM64::Encryption CHAM64Encryption;

/// \brief CHAM64 decryption

typedef CHAM64::Decryption CHAM64Decryption;

/// \brief CHAM 128-bit block cipher

/// \details CHAM128 provides 128-bit block size. The valid key size is 128-bit and 256-bit.

/// \note Crypto++ provides a byte oriented implementation

/// \sa CHAM64, <a href="http://www.cryptopp.com/wiki/CHAM">CHAM</a>,

///   <a href="https://pdfs.semanticscholar.org/2f57/61b5c2614cffd58a09cc83c375a2b32a2ed3.pdf">

///   CHAM: A Family of Lightweight Block Ciphers for Resource-Constrained Devices</a>

/// \since Crypto++ 8.0

class CRYPTOPP_NO_VTABLE CHAM128 : public CHAM128_Info, public BlockCipherDocumentation

{

public:

    /// \brief CHAM block cipher transformation functions

    /// \details Provides implementation common to encryption and decryption

    /// \since Crypto++ 8.0

    class CRYPTOPP_NO_VTABLE Base : public BlockCipherImpl<CHAM128_Info>

    {

    protected:

        void UncheckedSetKey(const byte *userKey, unsigned int keyLength, const NameValuePairs &params);

        std::string AlgorithmProvider() const;

        SecBlock<word32> m_rk;

        mutable FixedSizeSecBlock<word32, 4> m_x;

        unsigned int m_kw;

    };

    /// \brief Encryption transformation

    /// \details Enc provides implementation for encryption transformation. All key and block

    ///   sizes are supported.

    /// \since Crypto++ 8.0

    class CRYPTOPP_NO_VTABLE Enc : public Base

    {

    public:

        void ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const;

#if CRYPTOPP_CHAM128_ADVANCED_PROCESS_BLOCKS

        size_t AdvancedProcessBlocks(const byte *inBlocks, const byte *xorBlocks, byte *outBlocks, size_t length, word32 flags) const;

#endif

    };

    /// \brief Decryption transformation

    /// \details Dec provides implementation for decryption transformation. All key and block

    ///   sizes are supported.

    /// \since Crypto++ 8.0

    class CRYPTOPP_NO_VTABLE Dec : public Base

    {

    public:

        void ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const;

#if CRYPTOPP_CHAM128_ADVANCED_PROCESS_BLOCKS

        size_t AdvancedProcessBlocks(const byte *inBlocks, const byte *xorBlocks, byte *outBlocks, size_t length, word32 flags) const;

#endif

    };

    /// \brief CHAM128 encryption

    typedef BlockCipherFinal<ENCRYPTION, Enc> Encryption;

    /// \brief CHAM128 decryption

    typedef BlockCipherFinal<DECRYPTION, Dec> Decryption;

};

/// \brief CHAM128 encryption

typedef CHAM128::Encryption CHAM128Encryption;

/// \brief CHAM128 decryption

typedef CHAM128::Decryption CHAM128Decryption;

NAMESPACE_END

#endif  // CRYPTOPP_CHAM_H