desdata.cpp

DES算法原理及实现,实现了3DES和DES的程序过程

/*
*	 Implementation file for class of representing des data block
*    Copyright (C) 2007  Stone
*
*    This program is free software: you can redistribute it and/or modify
*    it under the terms of the GNU General Public License as published by
*    the Free Software Foundation, either version 3 of the License, or
*    (at your option) any later version.
*
*    This program is distributed in the hope that it will be useful,
*    but WITHOUT ANY WARRANTY; without even the implied warranty of
*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
*    GNU General Public License for more details.
*
*    You should have received a copy of the GNU General Public License
*    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*
*    Contact me by [e-mail] 
*
*/
#include "StdAfx.h"
#include "desdata.h"
#include "deskey.h"
#include "spbitset.h"

desdata::data_t desdata::lo32(0XFFFFFFFF);

size_t desdata::ipb[] = 
{
	58,50,42,34,26,18,10,2,60,52,44,36,28,20,12,4,
	62,54,46,38,30,22,14,6,64,56,48,40,32,24,16,8,
	57,49,41,33,25,17,9,1,59,51,43,35,27,19,11,3,
	61,53,45,37,29,21,13,5,63,55,47,39,31,23,15,7
};
size_t desdata::ipr[] =
{
	40,8,48,16,56,24,64,32,39,7,47,15,55,23,63,31,
	38,6,46,14,54,22,62,30,37,5,45,13,53,21,61,29,
	36,4,44,12,52,20,60,28,35,3,43,11,51,19,59,27,
	34,2,42,10,50,18,58,26,33,1,41,9,49,17,57,25
};
size_t desdata::epd[] =
{
	32,1,2,3,4,5,4,5,6,7,8,9,
	8,9,10,11,12,13,12,13,14,15,16,17,
	16,17,18,19,20,21,20,21,22,23,24,25,
	24,25,26,27,28,29,28,29,30,31,32,1
};
size_t desdata::ppd[] =
{
	16,7,20,21,29,12,28,17,1,15,23,26,5,18,31,10,
	2,8,24,14,32,27,3,9,19,13,30,6,22,11,4,25
};
size_t desdata::sbx[8][4][16] =
{
	//1 
	14,4,13,1,2,15,11,8,3,10,6,12,5,9,0,7,
	0,15,7,4,14,2,13,1,10,6,12,11,9,5,3,8,
	4,1,14,8,13,6,2,11,15,12,9,7,3,10,5,0,
	15,12,8,2,4,9,1,7,5,11,3,14,10,0,6,13,
	//2
	15,1,8,14,6,11,3,4,9,7,2,13,12,0,5,10,
	3,13,4,7,15,2,8,14,12,0,1,10,6,9,11,5,
	0,14,7,11,10,4,13,1,5,8,12,6,9,3,2,15,
	13,8,10,1,3,15,4,2,11,6,7,12,0,5,14,9,
	//3
	10,0,9,14,6,3,15,5,1,13,12,7,11,4,2,8,
	13,7,0,9,3,4,6,10,2,8,5,14,12,11,15,1,
	13,6,4,9,8,15,3,0,11,1,2,12,5,10,14,7,
	1,10,13,0,6,9,8,7,4,15,14,3,11,5,2,12,
	//4
	7,13,14,3,0,6,9,10,1,2,8,5,11,12,4,15,
	13,8,11,5,6,15,0,3,4,7,2,12,1,10,14,9,
	10,6,9,0,12,11,7,13,15,1,3,14,5,2,8,4,
	3,15,0,6,10,1,13,8,9,4,5,11,12,7,2,14,
	//5
	2,12,4,1,7,10,11,6,8,5,3,15,13,0,14,9,
	14,11,2,12,4,7,13,1,5,0,15,10,3,9,8,6,
	4,2,1,11,10,13,7,8,15,9,12,5,6,3,0,14,
	11,8,12,7,1,14,2,13,6,15,0,9,10,4,5,3,
	//6
	12,1,10,15,9,2,6,8,0,13,3,4,14,7,5,11,
	10,15,4,2,7,12,9,5,6,1,13,14,0,11,3,8,
	9,14,15,5,2,8,12,3,7,0,4,10,1,13,11,6,
	4,3,2,12,9,5,15,10,11,14,1,7,6,0,8,13,
	//7
	4,11,2,14,15,0,8,13,3,12,9,7,5,10,6,1,
	13,0,11,7,4,9,1,10,14,3,5,12,2,15,8,6,
	1,4,11,13,12,3,7,14,10,15,6,8,0,5,9,2,
	6,11,13,8,1,4,10,7,9,5,0,15,14,2,3,12,
	//8
	13,2,8,4,6,15,11,1,10,9,3,14,5,0,12,7,
	1,15,13,8,10,3,7,4,12,5,6,11,0,14,9,2,
	7,11,4,1,9,12,14,2,0,6,10,13,15,3,5,8,
	2,1,14,7,4,10,8,13,15,12,9,0,3,5,6,11
};

desdata::desdata(void)
{
}

desdata::~desdata(void)
{
}

unsigned _int64 desdata::encrypt(const unsigned _int64& data,deskey& key)
{
	return des(data,key.begin(),key.end()); 
}

unsigned _int64 desdata::decrypt(const unsigned _int64& data,deskey& key)
{
	return des(data,key.rbegin(),key.rend());
}

template <class iterator>
unsigned _int64 desdata::des(const unsigned _int64& data,iterator begin,iterator end)
{
	unsigned _int64 result = 0;
	desdata::data_t d(data);
	d.extract(desdata::ipb,sizeof(desdata::ipb) / sizeof(desdata::ipb[0]));

	desdata::data_t right(d >> 32);
	desdata::data_t left(d & desdata::lo32);

	for (iterator i = begin; i != end; ++ i)
	{
		desdata::data_t ort(right);
		right.extract(desdata::epd,sizeof(desdata::epd) / sizeof(desdata::epd[0]));
		right ^= *i;
		sbox(right);
		right.extract(desdata::ppd,sizeof(desdata::ppd) / sizeof(desdata::ppd[0]));

		right ^= left;
		left = ort;
	}

	d = (left << 32) | right;

	d.extract(desdata::ipr,sizeof(desdata::ipr) / sizeof(desdata::ipr[0]));

	return d.to_ulonglong();
}

void desdata::sbox(desdata::data_t& right)
{
	unsigned _int64 result = 0;
	for (size_t i = 0; i < 8; ++ i)
	{
		size_t base = i * 6;
		size_t col = right.getbit(base) * 2 + right.getbit(base + 5);
		size_t row = right.getbit(base + 1) * 8 + right.getbit(base + 2) * 4 + right.getbit( base + 3) * 2 + right.getbit(base + 4);
		result |= (desdata::sbx[i][col][row] << (i * 4));
	}
	
	right = desdata::data_t(result);
}