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Encryption and compression, native and managed

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29 Jun 2012CPOL7 min read 111.1K   6.9K   92  
DLL for native encryption and compression (using Crypto++). Includes RSA Key Generator in C#, and encryption and compression in ASP.NET (C#).
#ifndef CRYPTOPP_ZLIB_H
#define CRYPTOPP_ZLIB_H

#include "adler32.h"
#include "zdeflate.h"
#include "zinflate.h"

NAMESPACE_BEGIN(CryptoPP)

/// ZLIB Compressor (RFC 1950)
class ZlibCompressor : public Deflator
{
public:
	ZlibCompressor(BufferedTransformation *attachment=NULL, unsigned int deflateLevel=DEFAULT_DEFLATE_LEVEL, unsigned int log2WindowSize=DEFAULT_LOG2_WINDOW_SIZE, bool detectUncompressible=true)
		: Deflator(attachment, deflateLevel, log2WindowSize, detectUncompressible) {}
	ZlibCompressor(const NameValuePairs &parameters, BufferedTransformation *attachment=NULL)
		: Deflator(parameters, attachment) {}

	unsigned int GetCompressionLevel() const;

protected:
	void WritePrestreamHeader();
	void ProcessUncompressedData(const byte *string, size_t length);
	void WritePoststreamTail();

	Adler32 m_adler32;
};

/// ZLIB Decompressor (RFC 1950)
class ZlibDecompressor : public Inflator
{
public:
	typedef Inflator::Err Err;
	class HeaderErr : public Err {public: HeaderErr() : Err(INVALID_DATA_FORMAT, "ZlibDecompressor: header decoding error") {}};
	class Adler32Err : public Err {public: Adler32Err() : Err(DATA_INTEGRITY_CHECK_FAILED, "ZlibDecompressor: ADLER32 check error") {}};
	class UnsupportedAlgorithm : public Err {public: UnsupportedAlgorithm() : Err(INVALID_DATA_FORMAT, "ZlibDecompressor: unsupported algorithm") {}};
	class UnsupportedPresetDictionary : public Err {public: UnsupportedPresetDictionary() : Err(INVALID_DATA_FORMAT, "ZlibDecompressor: unsupported preset dictionary") {}};

	/*! \param repeat decompress multiple compressed streams in series
		\param autoSignalPropagation 0 to turn off MessageEnd signal
	*/
	ZlibDecompressor(BufferedTransformation *attachment = NULL, bool repeat = false, int autoSignalPropagation = -1);
	unsigned int GetLog2WindowSize() const {return m_log2WindowSize;}

private:
	unsigned int MaxPrestreamHeaderSize() const {return 2;}
	void ProcessPrestreamHeader();
	void ProcessDecompressedData(const byte *string, size_t length);
	unsigned int MaxPoststreamTailSize() const {return 4;}
	void ProcessPoststreamTail();

	unsigned int m_log2WindowSize;
	Adler32 m_adler32;
};

NAMESPACE_END

#endif

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License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


Written By
Software Developer
Argentina Argentina
System developer from Argentina.

Programmed in VB 5,6,.NET, C#, Java, PL-SQL, Transac-SQL, C, C++ and even some "calculator" language.

Love to build small, useful applications.
Usually building big and complicated apps based on solid, reliable components.

Hobbies: reading, photography, chess, paddle, running.

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