dbtool/digest.h

// Copyright (C) 1999-2001 Open Source Telecom Corporation.
//  
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// it under the terms of the GNU General Public License as published by
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#ifndef	DIGEST_H
#define	DIGEST_H

#include <cstdio>

extern "C" {
#include <string.h>
}



/**
 * The digest base class is used for implementing and deriving one way
 * hashing functions.
 *
 * @author David Sugar <dyfet@ostel.com>
 * @short base class for hashing services.
 */
class Digest {
protected:
	Digest() {};

	/**
	 * Reset the digest table to an initial default value.
	 */
	virtual void initDigest(void) = 0;

	/**
	 * Get the size of a digest in octets.
	 *
	 * @return number of bytes in digest.
	 */
	virtual unsigned getSize(void) = 0;

	/**
	 * Copy the binary digest buffer to user memory.
	 *
	 * @return number of bytes in digest.
	 * @param buffer to write into.
	 */
	virtual unsigned getDigest(unsigned char *buffer) = 0;

	/**
	 * Put data into the digest bypassing the stream subsystem.
	 *
	 * @param buffer to read from.
	 * @param length of data.
	 */
	virtual void putDigest(unsigned char *buffer, unsigned length) = 0;

};


/**
 * A md5 collection/computation accululator class.
 *
 * @author David Sugar <dyfet@ostel.com>
 * @short md5 hash accumulation.
 */
class MD5Digest : public Digest
{
private:
	unsigned long state[4];
	unsigned long count[2];
	unsigned char buf[64];
	unsigned bpos;
	unsigned char md5[16];
	bool updated;

protected:
	int overflow(int c);

	void Update(void);

	void Commit(void);

public:
	MD5Digest();

	void initDigest(void);

	inline unsigned getSize(void)
		{return 16;};

	unsigned getDigest(unsigned char *buffer);

	void putDigest(unsigned char *buffer, unsigned len);

	char* stringDigest();
};


#endif