des.h

这是一个DES加密的源码,源码很小,如果有写的不好的地方,望谅解!

//des.h  
//***DES encrypt head file***
//***by yjm***
//***May. 2005***
#include <iostream.h>
#include <string.h>
char ch[256];//此处可修改一次接受传入的字符串长度(64的倍数)
unsigned int inf[64],inf1[64],k[64],parity(0),EP[48];//

char* encrypt(char pw[],char key[],bool jiami);
char NumToHex(int x);
char* HexToStr(char ch[]);
bool IsNum(char c);
int CharToNum(char c);
char* StrToHex(char ch[]);
int ip[64]={		
		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	};
	int ip1[64]={
		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};
	//S盒(1，2，...8)
	int s[8][64]=
	{
		{
			14,0,4,15,13,7,1,4,2,14,15,2,11,13,8,1,
			3,10,10,6,6,12,12,11,5,9,9,5,0,3,7,8,
			4,15,1,12,14,8,8,2,13,4,6,9,2,1,11,7,
			15,5,12,11,9,3,7,14,3,10,10,0,5,6,0,13},
		{
			15,3,1,13,8,4,14,7,6,15,11,2,3,8,4,14,	
			9,12,7,0,2,1,13,10,12,6,0,9,5,11,10,5,
			0,13,14,8,7,10,11,1,10,3,4,15,13,4,1,2,	
			5,11,8,6,12,7,6,12,9,0,3,5,2,14,15,9},
		{
			10,13,0,7,9,0,14,9,6,3,3,4,15,6,5,10,
			1,2,13,8,12,5,7,14,11,12,4,11,2,15,8,1,	
			13,1,6,10,4,13,9,0,8,6,15,9,3,8,0,7,
			11,4,1,15,2,14,12,3,5,11,10,5,14,2,7,12},
		{
			7,13,13,8,14,11,3,5,0,6,6,15,9,0,10,3,
			1,4,2,7,8,2,5,12,11,1,12,10,4,14,15,9,
			10,3,6,15,9,0,0,6,12,10,11,1,7,13,13,8,
			15,9,1,4,3,5,14,11,5,12,2,7,8,2,4,14},
		{
			2,14,12,11,4,2,1,12,7,4,10,7,11,13,6,1,	
			8,5,5,0,3,15,15,10,13,3,0,9,14,8,9,6,
			4,11,2,8,1,12,11,7,10,1,13,14,7,2,8,13,	
			15,6,9,15,12,0,5,9,6,10,3,4,0,5,14,3},
		{	
			12,10,1,15,10,4,15,2,9,7,2,12,6,9,8,5,
			0,6,13,1,3,13,4,14,14,0,7,11,5,3,11,8,
			9,4,14,3,15,2,5,12,2,9,8,5,12,15,3,10,
			7,11,0,14,4,1,10,7,1,6,13,0,11,8,6,13},
		{	
			4,13,11,0,2,11,14,7,15,4,0,9,8,1,13,10,	
			3,14,12,3,9,5,7,12,5,2,10,15,6,8,1,6,
			1,6,4,11,11,13,13,8,12,1,3,4,7,10,14,7,	
			10,9,15,5,6,0,8,15,0,14,5,2,9,3,2,12},
		{
			13,1,2,15,8,13,4,8,6,10,15,3,11,7,1,4,
			10,12,9,5,3,6,14,11,5,0,0,14,12,9,7,2,
			1,2,11,1,4,14,1,7,9,4,12,10,14,8,2,13,
			0,15,6,12,10,9,13,0,15,3,3,5,5,6,8,11}
	};
	int pc1[56]={	//密钥置换PC-1
			57,49,41,33,25,17,9,
			1,58,50,42,34,26,18,
			10,2,59,51,43,35,27,
			19,11,3,60,52,44,36,
			63,55,47,39,31,23,15,
			7,62,54,46,38,30,22,	
			14,6,61,53,45,37,29,	
			21,13,5,28,20,12,4};
	int pc2[48]={	//密钥置换PC-2
			14,17,11,24,1,5,
			3,28,15,6,21,10,	
			23,19,12,4,26,8,	
			16,7,27,20,13,2,
			41,52,31,37,47,55,
			30,40,51,45,33,48,	
			44,49,39,56,34,53,	
			46,42,50,36,29,32};
	int E[48]=		//扩展运算E
	{
			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};
	int P[32]=		//置换P
	{
			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};


unsigned int cd[56],ki[16][48],kt[56],c[8],f[32];
void LS(int n)   //密钥左移函数
{
	int c0,d0,c1,d1;
	c0=cd[0];
	c1=cd[1];
	d0=cd[28];
	d1=cd[29];
	if(n==1||n==2||n==9||n==16)
	{
		for(int i=0;i<55;i++)	
			cd[i]=cd[i+1];	
		cd[27]=c0;
		cd[55]=d0;
	}
	else{
		for(int i=0;i<54;i++)
			cd[i]=cd[i+2];
		cd[26]=c0;
		cd[27]=c1;
		cd[54]=d0;
		cd[55]=d1;
	}
}
char* encrypt(char pw[],char key[],bool jiami)
{	
	char *p,*p1; 
	p=pw;
	p1=key;
	int temp;
	//产生初始密钥流(64 bit).............可以自动扩展密钥长度 取前8字节
	for(int i=0;i<8;i++)
	{
		if(*p1=='\0')
			p1=key;		
		temp=int(*p1);
		for(int j=0;j<7;j++)
		{			
			k[8*i-j+6]=temp%2;
			parity+=temp%2;
			temp/=2;
		};
		k[8*(i+1)-1]=parity%2;
		parity=0;
		p1++;
	}	
//密钥置换 PC-1	
	for(i=0;i<28;i++)
	{
		cd[i]=k[pc1[i]-1];
		cd[i+28]=k[pc1[i+28]-1];			
	}	
	
//密钥置换 PC-2 &&产生Ki(i=1,2...16)
	for(i=0;i<16;i++)
	{
		LS(i+1);
		for(int j=0;j<48;j++)		
			ki[i][j]=cd[pc2[j]-1];		
	}

	//////////////////......................................................	
	int len=strlen(pw),len1(0),*pp,*pp1;
	if(len%16>0)
		len1=16-len%16;
	pp=new int [(len+len1)*4];
	pp1=new int [(len+len1)*4];
	
	if(len1>0)
		for(int i=0;i<4*len1;i++)
			pp[len*4+i]=0;//不足64bit时用0补齐
	
	for(int t=0;t<len;t++)//明文组
	{
		temp=int(*(p+t));
		if(temp<=57&&temp>=48)
			temp-=48;
		else if(temp<=90&&temp>=65)
			temp-=55;
		for(int i=0;i<4;i++)
		{
			pp[4*t-i+3]=temp%2;
			temp/=2;			
		}	
	}	

	for(t=0;t<(len-1)/16+1;t++)//明文按64bit分组
	{
		for(int i=0;i<64;i++)		
				inf1[i]=pp[t*64+i];	
			
		for(int m=0;m<64;m++)	
			inf[m]=inf1[ip[m]-1];	
		//距阵分左右2边 L0 (0-31)和 R0(32-63)		
		//f函数运算		
		for(int kx=0;kx<16;kx++)
		{			//对Ri作E扩展			
			for(int j=0;j<48;j++)
			{			//A(32bit)⊕E→E(A)(48bit)	...		 E(A)⊕J
				if(jiami)
					EP[j]=inf[E[j]+31]^ki[kx][j];//加密********************
				else
					EP[j]=inf[E[j]+31]^ki[15-kx][j];//解密*****************
			}		
			for(j=0;j<8;j++)
			{
				temp=EP[j*6]*32+EP[j*6+1]*16+EP[j*6+2]*8+EP[j*6+3]*4+EP[j*6+4]*2+EP[j*6+5];
				c[j]=s[j][temp];
				for(int k=0;k<4;k++)//48bit--->32bit
				{
					EP[4*j+3-k]=c[j]%2;
					c[j]/=2;			
				}					
			}			
			for(j=0;j<32;j++)
			{			 //P置换→f(A,J)(32bit)			
				f[j]=inf[j]^EP[P[j]-1];//L⊕f(R,K)
				if(kx!=15)
				{
					inf[j]=inf[j+32];
					inf[j+32]=f[j];
				}
				else			
					inf[j]=f[j];
			}
			
		}
		
		//逆初始置换IP-1
		for(i=0;i<64;i++)	
			pp1[64*t+i]=inf[ip1[i]-1];	
	}

	temp=(len+len1);	
	char tt[256];//对应ch的长度
	for(i=0;i<temp;i++)	
		tt[i]=NumToHex(pp1[4*i]*8+pp1[4*i+1]*4+pp1[4*i+2]*2+pp1[4*i+3]);	
	tt[temp]='\0';///
	strcpy(ch,tt);

	delete pp;
	delete pp1;
//	AfxMessageBox(ch);	
	return ch;
}
char NumToHex(int x)
{	
	if(x>=0&&x<=9)
		return char(x+48);
	if(x>=10&&x<=15)
		return char(x+55);
	return '?';
}
char* HexToStr(char ch[])
{
	int len=strlen(ch)/2,temp;
	for(int i=0;i<len;i++)
	{	
		temp=CharToNum(ch[2*i])*16+CharToNum(ch[2*i+1]);
		if(temp>127)
			temp=128-temp;
		ch[i]=char(temp);	
	}
	ch[len]='\0';
	return ch;
}
bool IsNum(char c)
{
	if(c<='9'&&c>='0')
		return true;
	else 
		return false;
}
int CharToNum(char c)
{
	if(c<='9'&&c>='0')
		return int(c)-48;
	if(c<='Z'&&c>='A')
		return int(c)-55;
	if(c<='z'&&c>='a')
		return int(c)-87;
	return -1;
}
char* StrToHex(char* ch)
{
	int len=lstrlen(ch),n;
	char str[256];
	memset(str,0,256);
	memcpy(str,ch,strlen(ch));
	for(int i=len-1;i>=0;i--)
	{
		n=int(str[i]);
		if(n<0)
			n=128-n;	
		str[2*i]=NumToHex((n&0xf0)/16);
		str[2*i+1]=NumToHex(n&0x0f);	
	}
	//follow for DES's 64bit in////
	///////////////////////////////
//	str[len*2]='\0';
	strcpy(ch,str);
	
	return ch;	
}