~zooko/cryptopp/trunk

#ifndef CRYPTOPP_AUTHENC_H

#define CRYPTOPP_AUTHENC_H

#include "cryptlib.h"

#include "secblock.h"

NAMESPACE_BEGIN(CryptoPP)

//! .

class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE AuthenticatedSymmetricCipherBase : public AuthenticatedSymmetricCipher

{

public:

	AuthenticatedSymmetricCipherBase() : m_state(State_Start) {}

	bool IsRandomAccess() const {return false;}

	bool IsSelfInverting() const {return true;}

	void UncheckedSetKey(const byte *,unsigned int,const CryptoPP::NameValuePairs &) {assert(false);}

	void SetKey(const byte *userKey, size_t keylength, const NameValuePairs &params);

	void Restart() {if (m_state > State_KeySet) m_state = State_KeySet;}

	void Resynchronize(const byte *iv, int length=-1);

	void Update(const byte *input, size_t length);

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

	void TruncatedFinal(byte *mac, size_t macSize);

protected:

	void AuthenticateData(const byte *data, size_t len);

	const SymmetricCipher & GetSymmetricCipher() const {return const_cast<AuthenticatedSymmetricCipherBase *>(this)->AccessSymmetricCipher();};

	virtual SymmetricCipher & AccessSymmetricCipher() =0;

	virtual bool AuthenticationIsOnPlaintext() const =0;

	virtual unsigned int AuthenticationBlockSize() const =0;

	virtual void SetKeyWithoutResync(const byte *userKey, size_t keylength, const NameValuePairs &params) =0;

	virtual void Resync(const byte *iv, size_t len) =0;

	virtual size_t AuthenticateBlocks(const byte *data, size_t len) =0;

	virtual void AuthenticateLastHeaderBlock() =0;

	virtual void AuthenticateLastConfidentialBlock() {}

	virtual void AuthenticateLastFooterBlock(byte *mac, size_t macSize) =0;

	enum State {State_Start, State_KeySet, State_IVSet, State_AuthUntransformed, State_AuthTransformed, State_AuthFooter};

	State m_state;

	unsigned int m_bufferedDataLength;

	lword m_totalHeaderLength, m_totalMessageLength, m_totalFooterLength;

	AlignedSecByteBlock m_buffer;

};

NAMESPACE_END

#endif