des.cpp

一个好的DES程序.可能程序不是很完整,希望大家多多指教

#include<stdio.h>
int p1[]={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};//初始置换Ip
int p2[]={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};//逆初始置换Ip-1
int p3[]={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};//选择置换PC-1
int p4[]={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};//选择置换PC-2
int 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};//位选择函数
int 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};//置换函数P
int s[9][20][20]={
	{{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}},
	{{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}},
	{{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},{0,10,13,0,6,9,8,7,4,15,14,3,11,5,2,12}},
	{{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}},
	{{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}},
	{{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}},
	{{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}},
	{{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}}};
//S盒
int k[17][66];//密钥为全局变量
char ch[999999];
void create_my(int my[])//产生16个密钥
{
	int my_k[66],i,n,d[34];
	int c[66],j,len_my,rrr,rr;
	//for(i=1;i<=64;i++)printf("%d",my[i]);printf("\n");
    for(i=0;i<56;i++)
	{
		c[i+1]=my[p3[i]];//选择置换后的密钥
		//printf("%d",c[i+1]);
	}//printf("\n");
	n=16;
	for(j=1;j<=28;j++)d[j]=c[28+j];
	for(i=1;i<=16;i++)
	{
		//printf("i=%d\n",i);
		if((i==1)||(i==2)||(i==9)||(i==16))
		{
			rr=c[1];
			for(j=2;j<=28;j++)c[j-1]=c[j];c[28]=rr;
			rr=d[1];
			for(j=2;j<=28;j++)d[j-1]=d[j];d[28]=rr;
		}
		else 
		{
			rr=c[1];rrr=c[2];
			for(j=3;j<=28;j++)c[j-2]=c[j];
			c[28]=rrr;c[27]=rr;
			rr=d[1];rrr=d[2];
			for(j=3;j<=28;j++)d[j-2]=d[j];
			d[28]=rrr;d[27]=rr;
		}
		for(j=29;j<=56;j++)c[j]=d[j-28];
		//for(j=1;j<=28;j++)printf("%d",c[j]);printf("\n");
		//for(j=1;j<=28;j++)printf("%d",d[j]);printf("\n");
		for(j=1;j<=48;++j)k[i][j]=c[p4[j-1]];//k[][]为16个密钥
		//for(j=1;j<=48;j++)printf(/*"k[%d][%d]=%d "*/"%d",k[i][j]);
		//printf("\n");
		//i++;
	}
}
void yihuo(int enlar[],int t[])
{
	int i;
	for(i=1;i<=48;i++)
		if(enlar[i]==t[i])enlar[i]=0;
		else enlar[i]=1;
}
void encord(int ming[])//ming[]数组下标是从1开始的到64
{
	int i,j,n,y,rr,t,x,pp,ming_1[66],aa[34];
	int me[66],me_1[66],r[34],l[34],enlarge[66];
	for(i=1;i<=64;i++)ming_1[i]=ming[p1[i-1]];//初始IP置换,保存在数组ming_1中
	//for(i=1;i<=64;i++)printf("%d",ming_1[i]);printf("\n");
	//01000001 01000010 01000011 01000100 01000101 01000110 01000111 01001000
	//11111111 00000000 01111000 01010101 00000000 00000000 10000000 01100110
	for(i=1;i<=32;i++){l[i]=ming_1[i]; r[i]=ming_1[32+i];}
	//printf("进行16次处理之前的左32位和右32位的输出显示:\n");
	//for(i=1;i<=32;i++)printf("%d",l[i]);printf("\n");
	//for(i=1;i<=32;i++)printf("%d",r[i]);printf("\n");
	for(i=1;i<=16;i++)
	{
		for(j=1;j<=32;j++)aa[j]=r[j];
		//printf("第%d次处理前的非扩展数的显示:",i);\
		//for(j=1;j<=32;j++)printf("%d",r[j]);
		//printf("第%d次处理扩展函数的显示(32->48位)\n",i);
		for(j=1;j<=48;j++)enlarge[j]=r[e[j-1]];//将32位R[]函数扩展为48位，直接调用e数组扩展
		//for(j=1;j<=48;j++)printf("%d",enlarge[j]);printf("\n");
		yihuo(enlarge,k[i]);//异或运算的结果保存在数组enlarge[]中
		//for(j=1;j<=48;j++)printf("%d",enlarge[j]);printf("\n");
		for(j=0;j<=34;j++)me[j]=0;//幂文初始化为0,32位的数组
		for(int i0=0;i0<=33;i0++)me[i0]=0;
		for(j=1;j<=48;j+=6)
		{
			//for(int i1=j;i1<=j+5;i1++)printf("%d",me[i1]);printf("\n");
			rr=enlarge[j]*2+enlarge[j+5];
			t=enlarge[j+1]*8+enlarge[j+2]*4+enlarge[j+3]*2+enlarge[j+4];
			x=s[(j/6)][rr][t];//x是S盒中的p,r,t对应的元素，下一步要将x转化为四位的二进质数
			y=(j/6+1)*4;
			//printf("rr=%d c=%d j=%d s=%d\n",rr,t,(j/6),x);
            while(x)
			{
				me[y--]=x%2;  //密文保存在数组me[]中,下标从1开始
				x/=2;
			}
			//printf("压缩后的字符显示:\n");
			//for(int ii=j/6*4+1;ii<=(j/6+1)*4;ii++)printf("%d",me[ii]);printf("\n");
		}//压缩后的字符保存在数组me[]中，6位压缩为4位
		for(j=1;j<=32;j++)r[j]=me[p[j-1]];//p置换,进行了一轮变换后的r[]数组
		yihuo(r,l);
		//for(j=1;j<=32;j++)r[j]=me[j];
		for(j=1;j<=32;j++)l[j]=aa[j];
		//printf("进行%d次处理之前的左32位和右32位的输出显示:\n",i);
	}//进行16轮f变换
	printf("加密后的密文的结果显示\n");
	for(i=1;i<=32;i++)me[i]=r[i];
    for(i=1;i<=32;i++)me[32+i]=l[i];
	for(i=1;i<=64;i++)me_1[i]=me[p2[i-1]];//进行逆初始变换IP
	//for(i=1;i<=64;i++)printf("%d",me_1[i]);printf("\n");
	int cp;char cc;
	for(i=1;i<=8;i++)//
	{
	    cp=0;
     	for(j=(i-1)*8+1;j<=i*8;j++)cp=me_1[j]+2*cp;
     	cc=char(cp);
      printf("%d %c\n",cp,cc);
    }   	
}//加密函数
void decord(int me[])
{
    int cp,aa[34];
	int me_1[66],l[34],r[34],x,y,pp,enlarge[66],i,j,rr,t,ming[66],ming_1[66];
	for(i=1;i<=64;i++)me_1[i]=me[p1[i-1]];//初始IP置换，保存在数组me_1中
	for(i=1;i<=32;i++){l[i]=me_1[i]; r[i]=me_1[32+i];}
	for(i=1;i<=16;i++)
	{
		for(j=1;j<=32;j++)aa[j]=r[j];
		for(j=1;j<=48;j++)enlarge[j]=r[e[j-1]];//将32位R[]函数扩展为48位，直接调用e数组扩展
		yihuo(enlarge,k[16-i+1]);//异或运算的结果保存在数组enlarge[]中
		for(j=1;j<=34;j++)ming[j]=0;
		for(j=1;j<=48;j+=6)
		{
			rr=enlarge[j]*2+enlarge[j+5];
			t=enlarge[j+1]*8+enlarge[j+2]*4+enlarge[j+3]*2+enlarge[j+4];
			x=s[j/6][rr][t];//x是S盒中的p,r,t对应的元素，下一步要将x转化为四位的二进质数
			y=(j/6+1)*4;
            while(x)
			{
				ming[y--]=x%2;  //明文保存在数组ming[]中,下标从1开始
				x/=2;
			}
		}//压缩后的字符保存在数组ming[]中，6位压缩为4位
		for(j=1;j<=32;j++)r[j]=ming[p[j-1]];//进行了一轮变换后的r[]数组
		yihuo(r,l);
		for(j=1;j<=32;j++)l[j]=aa[j]; 
	}//进行16轮f变换
	printf("解密后的明文的结果显示\n");
	for(i=1;i<=32;i++)ming[i]=r[i];
    for(i=1;i<=32;i++)ming[32+i]=l[i];
	for(i=1;i<=64;i++)ming_1[i]=ming[p2[i-1]];//进行逆初始变换IP
	for(i=1;i<=64;i++)printf("%d",ming_1[i]);printf("\n");
	for(i=1;i<=8;i++)
	{
	    cp=0;
	    for(j=(i-1)*8+1;j<=i*8;j++)cp=ming_1[j]+2*cp;
	    printf("%d %c\n",cp,char(cp));
    }
	//printf("\n");
}//解密函数



int main()
{
    int i,j,jj,m,n,t,x;
	int a[66],my[68];
	char myy[9];
	int pp;
	while(1)
	{
		printf("您好!您现在登录的是加密解密系统,欢迎光临!此系统现在仅有加密功能和解密功能,请选择:\n");
		printf("请输入密钥K\n");
		for(i=0;i<66;i++)my[i]=0;
        for(i=0;i<8;i++)scanf("%c",&myy[i]);
		for(i=0;i<8;i++)
		{
			x=int(myy[i]);
			j=(i+1)*8;
			while(x)
			{
				my[j]=x%2;
				//printf("j=%d my[%d]=%d ",j,j,my[j]);
				x/=2;
				j--;
			}
		}//将密钥字符转化为0,1串
		//printf("\n");
		//01000001 01000010 01000011 01000100 01000101 01000110 01000111 01001000
		//01000001 01000010 01000011 01000100 01000101 01000110 01000111 01001000
		/*for(i=1;i<=64;i++)
		{
		    printf("%d",my[i]);
		}*/
		//printf("\n");
		for(i=1;i<=16;i++)
			for(j=1;j<=16;j++)k[i][j]=0;
		create_my(my);
		printf("密钥的输出显示:\n");
		for(i=1;i<=16;i++)
		{
			for(j=1;j<=16;j++)printf("%d",k[i][j]);
			printf("\n");	
		}
		printf("选1:加密\n");
		printf("选2:解密\n");
		printf("选0:退出本系统\n");
		scanf("%d",&pp);
		gets(ch);//特别要注意，一定要用这个语句把它吃掉 
		if(pp==0)break;
		if(pp==1)
		{
		   printf("请输入一串字符，将字符转换为0,1明文是自动的\n");
		   for(j=1;;j++)
		   {
			   scanf("%c",&ch[j]);
			   if(ch[j]=='#'){ch[j]='\0';break;}
		   }
		   int tt=1;
		   int xxx;
		   for(i=tt;ch[i]!='\0';i+=8)
		   {
			   for(t=0;t<66;t++)a[t]=0;
			   for(pp=i,xxx=1;pp<i+8;xxx++,pp++)
			   {
				   x=int(ch[pp]);
				   t=xxx*8;
				   while(x>0)
				   {
					   a[t]=x%2;
					   x/=2;
					   t--;
				   }
			   }
			   //for(i=1;i<=64;i++){printf("%d",a[i]);/*if(i%8==0)printf("\n");*/}
			   encord(a);//加密    //从这里开始还没有检查，应该有点小问题吧，尤其是encord()
		   }//for
		}//if(pp=1)的情况调用加密函数
		else if(pp==2)
		{
			printf("请输入一串字符，将字符转换为0,1密文是自动的\n");
			for(i=1;;i++)
			{
				scanf("%c",&ch[i]);
				if(i%8==0)
				{
					for(t=1;t<=66;t++)a[t]=0;//a[]数组下标从1开始到64，将8个字符转化为密文0,1串，保存在数组a[]中
					for(j=i-7;j<=i;j++)
					{
						x=ch[j];t=8*j;
						while(x)
						{
					      a[t]=x%2;
					      x/=2;
					      t--;
						}
					}
					decord(a);//解密
				}//if
			}//for
		}//if(pp=2)的情况调用解密函数
		else printf("选择有误，请重新选择\n");
	}
}