des.cpp

数据加密的工具源代码

// DES.cpp: implementation of the DES class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "DES.h"
#include "des_array.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CDES::CDES()
{

} 

CDES::~CDES()
{

}

////////////////////////////////////////////////////////////////////
void CDES::deskey(unsigned char * key,short edf)
{
	int i, j, l, m, n;
	unsigned char pc1m[56], pcr[56];
	unsigned long kn[32];

	for ( j = 0; j < 56; j++ ) {
		l = pc1[j];
		m = l & 07;
		pc1m[j] = (key[l >> 3] & bytebit[m]) ? 1 : 0;
		}
	for( i = 0; i < 16; i++ ) {
		if( edf == DESCRYPT ) m = (15 - i) << 1;
		else m = i << 1;
		n = m + 1;
		kn[m] = kn[n] = 0L;
		for( j = 0; j < 28; j++ ) {
			l = j + totrot[i];
			if( l < 28 ) pcr[j] = pc1m[l];
			else pcr[j] = pc1m[l - 28];
			}
		for( j = 28; j < 56; j++ ) {
		    l = j + totrot[i];
		    if( l < 56 ) pcr[j] = pc1m[l];
		    else pcr[j] = pc1m[l - 28];
		    }
		for( j = 0; j < 24; j++ ) {
			if( pcr[pc2[j]] ) kn[m] |= bigbyte[j];
			if( pcr[pc2[j+24]] ) kn[n] |= bigbyte[j];
			}
		}
	cookey(kn);
	return;
}

void CDES::cookey(unsigned long * raw1)
{
	unsigned long *cook, *raw0;
	unsigned long dough[32];
	int i;

	cook = dough;
	for( i = 0; i < 16; i++, raw1++ ) {
		raw0 = raw1++;
		*cook	 = (*raw0 & 0x00fc0000L) << 6;
		*cook	|= (*raw0 & 0x00000fc0L) << 10;
		*cook	|= (*raw1 & 0x00fc0000L) >> 10;
		*cook++ |= (*raw1 & 0x00000fc0L) >> 6;
		*cook	 = (*raw0 & 0x0003f000L) << 12;
		*cook	|= (*raw0 & 0x0000003fL) << 16;
		*cook	|= (*raw1 & 0x0003f000L) >> 4;
		*cook++ |= (*raw1 & 0x0000003fL);
		}
	usekey(dough);
	return;
	}

void CDES::cpkey(unsigned long * into)
{
	unsigned long *from, *endp;

	from = KnL, endp = &KnL[32];
	while( from < endp ) *into++ = *from++;
	return;
	}

void CDES::usekey(unsigned long * from)
{
	unsigned long *to, *endp;

	to = KnL, endp = &KnL[32];
	while( to < endp ) *to++ = *from++;
	return;
	}

void CDES::des(unsigned char * inblock,unsigned char * outblock)
{
	unsigned long work[2];
	scrunch(inblock, work);
	desfunc(work, KnL);
	unscrun(work, outblock);
	return;
}

void CDES::scrunch(unsigned char * outof, unsigned long * into)
{
	*into	 = (*outof++ & 0xffL) << 24;
	*into	|= (*outof++ & 0xffL) << 16;
	*into	|= (*outof++ & 0xffL) << 8;
	*into++ |= (*outof++ & 0xffL);
	*into	 = (*outof++ & 0xffL) << 24;
	*into	|= (*outof++ & 0xffL) << 16;
	*into	|= (*outof++ & 0xffL) << 8;
	*into	|= (*outof   & 0xffL);
	return;
}

void CDES::unscrun(unsigned long * outof, unsigned char * into)
{
	*into++ = (*outof >> 24) & 0xffL;
	*into++ = (*outof >> 16) & 0xffL;
	*into++ = (*outof >>  8) & 0xffL;
	*into++ =  *outof++	 & 0xffL;
	*into++ = (*outof >> 24) & 0xffL;
	*into++ = (*outof >> 16) & 0xffL;
	*into++ = (*outof >>  8) & 0xffL;
	*into	=  *outof	 & 0xffL;
	return;
	}


void CDES::desfunc(unsigned long * block, unsigned long * keys)
{
	unsigned long fval, work, right, leftt;
	int round;

	leftt = block[0];
	right = block[1];
	work = ((leftt >> 4) ^ right) & 0x0f0f0f0fL;
	right ^= work;
	leftt ^= (work << 4);
	work = ((leftt >> 16) ^ right) & 0x0000ffffL;
	right ^= work;
	leftt ^= (work << 16);
	work = ((right >> 2) ^ leftt) & 0x33333333L;
	leftt ^= work;
	right ^= (work << 2);
	work = ((right >> 8) ^ leftt) & 0x00ff00ffL;
	leftt ^= work;
	right ^= (work << 8);
	right = ((right << 1) | ((right >> 31) & 1L)) & 0xffffffffL;
	work = (leftt ^ right) & 0xaaaaaaaaL;
	leftt ^= work;
	right ^= work;
	leftt = ((leftt << 1) | ((leftt >> 31) & 1L)) & 0xffffffffL;

	for( round = 0; round < 8; round++ ) {
		work  = (right << 28) | (right >> 4);
		work ^= *keys++;
		fval  = SP7[ work		 & 0x3fL];
		fval |= SP5[(work >>  8) & 0x3fL];
		fval |= SP3[(work >> 16) & 0x3fL];
		fval |= SP1[(work >> 24) & 0x3fL];
		work  = right ^ *keys++;
		fval |= SP8[ work		 & 0x3fL];
		fval |= SP6[(work >>  8) & 0x3fL];
		fval |= SP4[(work >> 16) & 0x3fL];
		fval |= SP2[(work >> 24) & 0x3fL];
		leftt ^= fval;
		work  = (leftt << 28) | (leftt >> 4);
		work ^= *keys++;
		fval  = SP7[ work		 & 0x3fL];
		fval |= SP5[(work >>  8) & 0x3fL];
		fval |= SP3[(work >> 16) & 0x3fL];
		fval |= SP1[(work >> 24) & 0x3fL];
		work  = leftt ^ *keys++;
		fval |= SP8[ work		 & 0x3fL];
		fval |= SP6[(work >>  8) & 0x3fL];
		fval |= SP4[(work >> 16) & 0x3fL];
		fval |= SP2[(work >> 24) & 0x3fL];
		right ^= fval;
		}

	right = (right << 31) | (right >> 1);
	work = (leftt ^ right) & 0xaaaaaaaaL;
	leftt ^= work;
	right ^= work;
	leftt = (leftt << 31) | (leftt >> 1);
	work = ((leftt >> 8) ^ right) & 0x00ff00ffL;
	right ^= work;
	leftt ^= (work << 8);
	work = ((leftt >> 2) ^ right) & 0x33333333L;
	right ^= work;
	leftt ^= (work << 2);
	work = ((right >> 16) ^ leftt) & 0x0000ffffL;
	leftt ^= work;
	right ^= (work << 16);
	work = ((right >> 4) ^ leftt) & 0x0f0f0f0fL;
	leftt ^= work;
	right ^= (work << 4);
	*block++ = right;
	*block = leftt;
	return;
}
////////////////////////////////////////////////////////////////////////

#define useDkey(a) use2key(a)
#define cpDkey(a) cp2key(a)
void CDES::des2key(unsigned char *hexkey,short mode)		
{
	short revmod;

	revmod = (mode == ENCRYPT) ? DESCRYPT : ENCRYPT;
	deskey(&hexkey[8], revmod);
	cpkey(KnR);
	deskey(hexkey, mode);
	cpkey(Kn3);				
	return;
	}

void CDES::Ddes(unsigned char *from,unsigned char *into)
{
	unsigned long work[2];

	scrunch(from, work);
	desfunc(work, KnL);
	desfunc(work, KnR);
	desfunc(work, Kn3);
	unscrun(work, into);
	return;
	}

void CDES::D2des(unsigned char *from, unsigned char *into)
{
	unsigned long *right, *l1, swap;
	unsigned long leftt[2], bufR[2];

	right = bufR;
	l1 = &leftt[1];
	scrunch(from, leftt);
	scrunch(&from[8], right);
	desfunc(leftt, KnL);
	desfunc(right, KnL);
	swap = *l1;
	*l1 = *right;
	*right = swap;
	desfunc(leftt, KnR);
	desfunc(right, KnR);
	swap = *l1;
	*l1 = *right;
	*right = swap;
	desfunc(leftt, Kn3);
	desfunc(right, Kn3);
	unscrun(leftt, into);
	unscrun(right, &into[8]);
	return;
	}

void CDES::makekey(char *aptr,unsigned char *kptr)
{
	register unsigned char *store;
	register int first, i;
	unsigned long savek[96];

	cpDkey(savek);
	des2key(Df_Key, ENCRYPT);
	for( i = 0; i < 8; i++ ) kptr[i] = Df_Key[i];
	first = 1;
	while( (*aptr != '\0') || first ) {
		store = kptr;
		for( i = 0; i < 8 && (*aptr != '\0'); i++ ) {
			*store++ ^= *aptr & 0x7f;
			*aptr++ = '\0';
			}
		Ddes(kptr, kptr);
		first = 0;
		}
	useDkey(savek);
	return;
}

void CDES::make2key(char *aptr,unsigned char *kptr)
{
	register unsigned char *store;
	register int first, i;
	unsigned long savek[96];

	cpDkey(savek);
	des2key(Df_Key, ENCRYPT);
	for( i = 0; i < 16; i++ ) kptr[i] = Df_Key[i];
	first = 1;
	while( (*aptr != '\0') || first ) {
		store = kptr;
		for( i = 0; i < 16 && (*aptr != '\0'); i++ ) {
			*store++ ^= *aptr & 0x7f;
			*aptr++ = '\0';
			}
		D2des(kptr, kptr);
		first = 0;
		}
	useDkey(savek);
	return;
}

void CDES::cp2key(unsigned long *into)
{
	register unsigned long *from, *endp;

	cpkey(into);
	into = &into[32];
	from = KnR, endp = &KnR[32];
	while( from < endp ) *into++ = *from++;
	return;
	}

void CDES::use2key(unsigned long *from)				
{
	register unsigned long *to, *endp;

	usekey(from);
	from = &from[32];
	to = KnR, endp = &KnR[32];
	while( to < endp ) *to++ = *from++;
	cpkey(Kn3);					// Kn3 = KnL 
	return;
	}

void CDES::des3key(unsigned char *hexkey,short mode)
{
	unsigned char *first, *third;
	short revmod;

	if( mode == ENCRYPT ) {
		revmod = DESCRYPT;
		first = hexkey;
		third = &hexkey[16];
		}
	else {
		revmod = ENCRYPT;
		first = &hexkey[16];
		third = hexkey;
		}
	deskey(&hexkey[8], revmod);
	cpkey(KnR);
	deskey(third, mode);
	cpkey(Kn3);
	deskey(first, mode);
	return;
	}

void CDES::cp3key(unsigned long *into)
{
	register unsigned long *from, *endp;

	cpkey(into);
	into = &into[32];
	from = KnR, endp = &KnR[32];
	while( from < endp ) *into++ = *from++;
	from = Kn3, endp = &Kn3[32];
	while( from < endp ) *into++ = *from++;
	return;
	}

void CDES::use3key(unsigned long *from)
{
	register unsigned long *to, *endp;

	usekey(from);
	from = &from[32];
	to = KnR, endp = &KnR[32];
	while( to < endp ) *to++ = *from++;
	to = Kn3, endp = &Kn3[32];
	while( to < endp ) *to++ = *from++;
	return;
	}

void CDES::D3des(unsigned char *from,unsigned char *into)	
{
	unsigned long swap, leftt[2], middl[2], right[2];

	scrunch(from, leftt);
	scrunch(&from[8], middl);
	scrunch(&from[16], right);
	desfunc(leftt, KnL);
	desfunc(middl, KnL);
	desfunc(right, KnL);
	swap = leftt[1];
	leftt[1] = middl[0];
	middl[0] = swap;
	swap = middl[1];
	middl[1] = right[0];
	right[0] = swap;
	desfunc(leftt, KnR);
	desfunc(middl, KnR);
	desfunc(right, KnR);
	swap = leftt[1];
	leftt[1] = middl[0];
	middl[0] = swap;
	swap = middl[1];
	middl[1] = right[0];
	right[0] = swap;
	desfunc(leftt, Kn3);
	desfunc(middl, Kn3);
	desfunc(right, Kn3);
	unscrun(leftt, into);
	unscrun(middl, &into[8]);
	unscrun(right, &into[16]);
	return;
}

void CDES::make3key(char *aptr,unsigned char *kptr)
{
	register unsigned char *store;
	register int first, i;
	unsigned long savek[96];

	cp3key(savek);
	des3key(Df_Key, ENCRYPT);
	for( i = 0; i < 24; i++ ) kptr[i] = Df_Key[i];
	first = 1;
	while( (*aptr != '\0') || first ) {
		store = kptr;
		for( i = 0; i < 24 && (*aptr != '\0'); i++ ) {
			*store++ ^= *aptr & 0x7f;
			*aptr++ = '\0';
			}
		D3des(kptr, kptr);
		first = 0;
		}
	use3key(savek);
	return;
}