// serpent.h - originally written and placed in the public domain by Wei Dai

/// \file serpent.h

/// \brief Classes for the Serpent block cipher

/// \sa <a href="https://www.cl.cam.ac.uk/~rja14/serpent.html">A

///  Candidate Block Cipher for the Advanced Encryption Standard</a>

#ifndef CRYPTOPP_SERPENT_H

#define CRYPTOPP_SERPENT_H

#include "seckey.h"

#include "secblock.h"

NAMESPACE_BEGIN(CryptoPP)

/// \brief Serpent block cipher information

/// \since Crypto++ 3.1

struct Serpent_Info : public FixedBlockSize<16>, public VariableKeyLength<16, 16, 32, 8>, public FixedRounds<32>

{

  CRYPTOPP_STATIC_CONSTEXPR const char* StaticAlgorithmName() {return "Serpent";}

};

/// \brief Serpent block cipher

/// \sa <a href="http://www.cryptopp.com/wiki/Serpent">Serpent</a> on the

///  Crypto++ wiki, <a href="https://www.cl.cam.ac.uk/~rja14/serpent.html">A

///  Candidate Block Cipher for the Advanced Encryption Standard</a>

/// \since Crypto++ 3.1

class Serpent : public Serpent_Info, public BlockCipherDocumentation

{

  /// \brief Serpen block cipher base implementation

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

  /// \since Crypto++ 3.1

  class CRYPTOPP_NO_VTABLE Base : public BlockCipherImpl<Serpent_Info>

  {

  public:

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

  protected:

    FixedSizeSecBlock<word32, 33*4> m_key;

  };

  /// \brief Serpent encryption transformation

  /// \details Enc provides the encryption transformation.

  ///  All key sizes are supported.

  /// \since Crypto++ 3.1

  class CRYPTOPP_NO_VTABLE Enc : public Base

  {

  public:

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

  };

  /// \brief Serpent decryption transformation

  /// \details Dec provides the decryption transformation.

  ///  All key sizes are supported.

  /// \since Crypto++ 3.1

  class CRYPTOPP_NO_VTABLE Dec : public Base

  {

  public:

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

  };

public:

  typedef BlockCipherFinal<ENCRYPTION, Enc> Encryption;

  typedef BlockCipherFinal<DECRYPTION, Dec> Decryption;

};

typedef Serpent::Encryption SerpentEncryption;

typedef Serpent::Decryption SerpentDecryption;

NAMESPACE_END

#endif  // CRYPTOPP_SERPENT_H