/*
 * Compilation Copyright (c) 1995-2019 by Wei Dai.  All rights reserved.
 *	This copyright applies only to this software distribution package
 *	as a compilation, and does not imply a copyright on any particular
 *	file in the package.
 * 
 *	Boost Software License - Version 1.0 - August 17th, 2003
 *
 *	Permission is hereby granted, free of charge, to any person or organization
 *	obtaining a copy of the software and accompanying documentation covered by
 *	this license (the "Software") to use, reproduce, display, distribute,
 *	execute, and transmit the Software, and to prepare derivative works of the
 *	Software, and to permit third-parties to whom the Software is furnished to
 *	do so, all subject to the following:
 * 
 *	The copyright notices in the Software and this entire statement, including
 *	the above license grant, this restriction and the following disclaimer,
 *	must be included in all copies of the Software, in whole or in part, and
 *	all derivative works of the Software, unless such copies or derivative
 *	works are solely in the form of machine-executable object code generated by
 *	a source language processor.
 *
 *	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 *	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *	FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
 *	SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
 *	FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
 *	ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 *	DEALINGS IN THE SOFTWARE.
 */

// arc4.h - originally written and placed in the public domain by Wei Dai

/// \file arc4.h
/// \brief Classes for ARC4 cipher
/// \since Crypto++ 3.1

#ifndef CRYPTOPP_ARC4_H
#define CRYPTOPP_ARC4_H

#include "cryptlib.h"
#include "strciphr.h"
#include "secblock.h"
#include "smartptr.h"

NAMESPACE_BEGIN(CryptoPP)

namespace Weak1 {

/// \brief ARC4 base class
/// \details Implementations and overrides in \p Base apply to both \p ENCRYPTION and \p DECRYPTION directions
/// \since Crypto++ 3.1
class CRYPTOPP_NO_VTABLE ARC4_Base : public VariableKeyLength<16, 1, 256>, public RandomNumberGenerator, public SymmetricCipher, public SymmetricCipherDocumentation
{
public:
	~ARC4_Base();

	CRYPTOPP_STATIC_CONSTEXPR const char* StaticAlgorithmName() {return "ARC4";}

	void GenerateBlock(byte *output, size_t size);
	void DiscardBytes(size_t n);

    void ProcessData(byte *outString, const byte *inString, size_t length);

	bool IsRandomAccess() const {return false;}
	bool IsSelfInverting() const {return true;}
	bool IsForwardTransformation() const {return true;}

	typedef SymmetricCipherFinal<ARC4_Base> Encryption;
	typedef SymmetricCipherFinal<ARC4_Base> Decryption;

protected:
	void UncheckedSetKey(const byte *key, unsigned int length, const NameValuePairs &params);
	virtual unsigned int GetDefaultDiscardBytes() const {return 0;}

    FixedSizeSecBlock<byte, 256> m_state;
    byte m_x, m_y;
};

/// \brief Alleged RC4
/// \sa <a href="http://www.cryptopp.com/wiki/RC4">Alleged RC4</a>
/// \since Crypto++ 3.1
DOCUMENTED_TYPEDEF(SymmetricCipherFinal<ARC4_Base>, ARC4)

/// \brief MARC4 base class
/// \details Implementations and overrides in \p Base apply to both \p ENCRYPTION and \p DECRYPTION directions
/// \details MARC4 discards the first 256 bytes of keystream, which may be weaker than the rest
/// \since Crypto++ 3.1
class CRYPTOPP_NO_VTABLE MARC4_Base : public ARC4_Base
{
public:
	CRYPTOPP_STATIC_CONSTEXPR const char* StaticAlgorithmName() {return "MARC4";}

	typedef SymmetricCipherFinal<MARC4_Base> Encryption;
	typedef SymmetricCipherFinal<MARC4_Base> Decryption;

protected:
	unsigned int GetDefaultDiscardBytes() const {return 256;}
};

/// \brief Modified Alleged RC4
/// \sa <a href="http://www.cryptopp.com/wiki/RC4">Alleged RC4</a>
/// \since Crypto++ 3.1
DOCUMENTED_TYPEDEF(SymmetricCipherFinal<MARC4_Base>, MARC4)

}
#if CRYPTOPP_ENABLE_NAMESPACE_WEAK >= 1
namespace Weak {using namespace Weak1;}		// import Weak1 into CryptoPP::Weak
#else
using namespace Weak1;	// import Weak1 into CryptoPP with warning
#ifdef __GNUC__
#warning "You may be using a weak algorithm that has been retained for backwards compatibility. Please '#define CRYPTOPP_ENABLE_NAMESPACE_WEAK 1' before including this .h file and prepend the class name with 'Weak::' to remove this warning."
#else
#pragma message("You may be using a weak algorithm that has been retained for backwards compatibility. Please '#define CRYPTOPP_ENABLE_NAMESPACE_WEAK 1' before including this .h file and prepend the class name with 'Weak::' to remove this warning.")
#endif
#endif

NAMESPACE_END

#endif
