//
// $Id: MD5.h,v 1.4 2007/01/09 17:43:01 bakerj Exp $
//
//****************************************************************************************//
// Copyright (c) 2002-2007, The MITRE Corporation
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
//     * Redistributions of source code must retain the above copyright notice, this list
//       of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above copyright notice, this 
//       list of conditions and the following disclaimer in the documentation and/or other
//       materials provided with the distribution.
//     * Neither the name of The MITRE Corporation nor the names of its contributors may be
//       used to endorse or promote products derived from this software without specific 
//       prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY 
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
// OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
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//****************************************************************************************//
//
// MD5.cpp - source code for the C++/object oriented translation and 
//          modification of MD5.
//
// Translation and modification (c) 1995 by Mordechai T. Abzug 
//
// This translation/ modification is provided "as is," without express or 
// implied warranty of any kind.
//
// The translator/ modifier does not claim (1) that MD5 will do what you think 
// it does; (2) that this translation/ modification is accurate; or (3) that 
// this software is "merchantible."  (Language for this disclaimer partially 
// copied from the disclaimer below).
//
//****************************************************************************************//
//
// Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
// rights reserved.
//
// License to copy and use this software is granted provided that it
// is identified as the "RSA Data Security, Inc. MD5 Message-Digest
// Algorithm" in all material mentioning or referencing this software
// or this function.
// 
// License is also granted to make and use derivative works provided
// that such works are identified as "derived from the RSA Data
// Security, Inc. MD5 Message-Digest Algorithm" in all material
// mentioning or referencing the derived work.
// 
// RSA Data Security, Inc. makes no representations concerning either
// the merchantability of this software or the suitability of this
// software for any particular purpose. It is provided "as is"
// without express or implied warranty of any kind.
// 
// These notices must be retained in any copies of any part of this
// documentation and/or software.
// 
//****************************************************************************************//

#ifndef MD5_H
#define MD5_H

#include <assert.h>

#include <fstream>
#include <iostream>

using namespace std;

/**
	Provides md5 support to the application.
*/
class MD5 {

public:
// methods for controlled operation:
  MD5              ();  // simple initializer
  void  update     (unsigned char *input, unsigned int input_length);
  void  update     (FILE *file);
  void  finalize   ();

// constructors for special circumstances.  All these constructors finalize
// the MD5 context.
  MD5              (FILE *file);            // digest file, close, finalize

// methods to acquire finalized result
  unsigned char    *raw_digest ();  // digest as a 16-byte binary array
  char *            hex_digest ();  // digest as a 33-byte ascii-hex string
  friend ostream&   operator<< (ostream&, MD5 context);



private:

// first, some types:
  typedef unsigned       int uint4; // assumes integer is 4 words long
  typedef unsigned short int uint2; // assumes short integer is 2 words long
  typedef unsigned      char uint1; // assumes char is 1 word long

// next, the private data:
  uint4 state[4];
  uint4 count[2];     // number of *bits*, mod 2^64
  uint1 buffer[64];   // input buffer
  uint1 digest[16];
  uint1 finalized;

// last, the private methods, mostly static:
  void init             ();               // called by all constructors
  void transform        (uint1 *buffer);  // does the real update work.  Note 
                                          // that length is implied to be 64.

  static void encode    (uint1 *dest, uint4 *src, uint4 length);
  static void decode    (uint4 *dest, uint1 *src, uint4 length);
  static void memcpy    (uint1 *dest, uint1 *src, uint4 length);
  static void memset    (uint1 *start, uint1 val, uint4 length);

  static inline uint4  rotate_left (uint4 x, uint4 n);
  static inline uint4  F           (uint4 x, uint4 y, uint4 z);
  static inline uint4  G           (uint4 x, uint4 y, uint4 z);
  static inline uint4  H           (uint4 x, uint4 y, uint4 z);
  static inline uint4  I           (uint4 x, uint4 y, uint4 z);
  static inline void   FF  (uint4& a, uint4 b, uint4 c, uint4 d, uint4 x, 
			    uint4 s, uint4 ac);
  static inline void   GG  (uint4& a, uint4 b, uint4 c, uint4 d, uint4 x, 
			    uint4 s, uint4 ac);
  static inline void   HH  (uint4& a, uint4 b, uint4 c, uint4 d, uint4 x, 
			    uint4 s, uint4 ac);
  static inline void   II  (uint4& a, uint4 b, uint4 c, uint4 d, uint4 x, 
			    uint4 s, uint4 ac);

};

#endif
