des.c

DES算法

#include <stc12.h>
unsigned char r_sf_cnt,s_sf_cnt; 
////////////初始置换表Init_Table ///////////////////
unsigned char code Init_Table[64] = 
					{
						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,
                    	56,48,40,32,24,16,8,0,58,50,42,34,26,18,10,2,
                    	60,52,44,36,28,20,12,4,62,54,46,38,30,22,14,6
					}; 
////////////逆初始置换表IP^-1 ///////////////////////
unsigned char code Init_1_Table[64] = 
					{
						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,
		   				33,1,41,9,49,17,57,25,32,0,40,8,48,16,56,24
					};
////////////置换选择1  ///////////////////////////////
unsigned char code C_Rep_1[56] = 
					{
						56,48,40,32,24,16,8,0,57,49,41,33,25,17,
	         			9,1,58,50,42,34,26,18,10,2,59,51,43,35,
	         			62,54,46,38,30,22,14,6,61,53,45,37,29,21,
	          			13,5,60,52,44,36,28,20,12,4,27,19,11,3
					};
////////////置换选择2 ////////////////////////////////
unsigned char code C_Rep_2[48] = 
					{
						13,16,10,23,0,4,2,27,14,5,20,9,22,18,11,3,
	          			25,7,15,6,26,19,12,1,40,51,30,36,46,54,29,39,
	          			50,44,32,46,43,48,38,55,33,52,45,41,49,35,28,31
			  		};
////////////扩充置换表E/////////////////////////////
unsigned char code E_Table[48] =
					{
						31, 0, 1, 2, 3, 4,3,  4, 5, 6, 7, 8,
	              		7, 8,9,10,11,12,11,12,13,14,15,16,
	              		15,16,17,18,19,20,19,20,21,22,23,24,
	              		23,24,25,26,27,28,27,28,29,30,31, 0
				  	};

////////////置换函数F //////////////////////////////
unsigned char code F_Table[32] = 
					{
						15,6,19,20,28,11,27,16,0,14,22,25,4,17,30,9,
				 		1,7,23,13,31,26,2,8,18,12,29,5,21,10,3,24
				  	};
////////////S盒	 ///////////////////////////////////
unsigned char code S[8][4][16] =
			  //S1
 	     {{{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}},
  	          //S2
 	     {{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}},
 	           //S3
 	     {{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}},
 	           //S4
 	     {{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}},
 	           //S5
 	     {{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}},
 	           //S6
 	     {{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}},
 	           //S7
 	     {{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}},
 	           //S8
 	     {{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}}};		 
 
unsigned char code M_Times[16] = {1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1};	

///////////////中断服务程序,进行数据处理/////////////////////

void Serial_ISR(void)interrupt 4
{   					
	unsigned char Data_Block[8],Data_Bits[64],subKeys[48];
	unsigned char cnt0,cnt1,s_cnt1,s_cnt2; 
	unsigned char temp0[64],temp1[48];
	unsigned char line,row,output;   
	unsigned char Flag;
	
 	if(RI)
	{	
	  	RI=0;
		Data_Block[r_sf_cnt]=SBUF;
		r_sf_cnt++;
		if(r_sf_cnt==8)
    	 {	
			ES=0;
			Flag=0;
			r_sf_cnt=0;	 
			for(cnt0 = 0; cnt0 < 8; cnt0++)
	 			for(cnt1=0;cnt1<8;cnt1++)					     
					Data_Bits[(cnt0<<3)+cnt1]=(Data_Block[cnt0]>>cnt1)&1; 	// 转变为二进制数据流
   		////////////////进行16轮代换////////////////////////////////////	
			for(cnt0 = 0; cnt0 < 16; cnt0++)
				{ 
			 		//////////生成子密钥//////////////
					for(cnt1=0;cnt1<56;cnt1++)						 
						temp0[cnt1]=Data_Bits[C_Rep_1[cnt1]];		  		
					for(cnt1=0;cnt1<M_Times[cnt0];cnt1++)		//循环左移
						temp1[cnt1]=temp0[cnt1]; 
    				for(cnt1=0;cnt1<M_Times[cnt0];cnt1++) 	   	//保存将要循环移动到右边的位
						temp1[cnt1+M_Times[cnt0]]=temp0[cnt1+28]; 
    				for(cnt1=0;cnt1<28-M_Times[cnt0];cnt1++)		//前28位移动
						temp0[cnt1]=temp0[cnt1+M_Times[cnt0]];   
    				for(cnt1=0;cnt1<M_Times[cnt0];cnt1++)
						temp0[cnt1+28-M_Times[cnt0]]=temp1[cnt1];	    		 
    				for(cnt1=0;cnt1<28-M_Times[cnt0];cnt1++)		 //后28位移动
						temp0[cnt1+28]=temp0[cnt1+28+M_Times[cnt0]]; 	  
					for(cnt1=0;cnt1<M_Times[cnt0];cnt1++)
						temp0[cnt1+56-M_Times[cnt0]]=temp1[cnt1+M_Times[cnt0]];	    
					for(cnt1 = 0; cnt1 < 48; cnt1++)
       					subKeys[cnt1] = temp0[C_Rep_2[cnt1]];   //C_Rep_2置换，产生子密钥 
					 //////////Init_Table置换//////////////////
					if(Flag==0)								  
						{
							for(cnt1 = 0; cnt1 < 64; cnt1++)	   
       	    					temp0[cnt1] = Data_Bits[Init_Table[cnt1]];  
							for(cnt1=0;cnt1<64;cnt1++)
								Data_Bits[cnt1]=temp0[cnt1]; 
							Flag=1;	
						}	
					//////将右半部分进行从32位48位扩展置换/////////////						
			  		for(cnt1 = 0; cnt1 < 32; cnt1++) 
						temp0[cnt1]=  Data_Bits[cnt1+32];   
    	  	 		for(cnt1 = 0; cnt1 < 48; cnt1++)	          
        				temp1[cnt1] = temp0[E_Table[cnt1]]^subKeys[cnt1];   	//将右半部分与子密钥进行异或操作 
  				////////////异或结果进入S盒，输出32位结果 ////////////
   					for(cnt1 = 0; cnt1 < 8; cnt1++)				
						{   
        					s_cnt1 = cnt1*6;   
       						s_cnt2 = cnt1<<2;   
        					//计算在S盒中的行与列   
       						line = (temp1[s_cnt1]<<1) + temp1[s_cnt1+5];   
        					row = (temp1[s_cnt1+1]<<3) + (temp1[s_cnt1+2]<<2) + (temp1[s_cnt1+3]<<1) + temp1[s_cnt1+4];   
        					output = S[cnt1][line][row];   
        					//化为2进制   	为什么没有高四位？
       						temp1[s_cnt2] = (output&0X08)>>3;   
        					temp1[s_cnt2+1] = (output&0X04)>>2;   
        					temp1[s_cnt2+2] = (output&0X02)>>1;   
        					temp1[s_cnt2+3] = output&0x01;   
   						}      
	 				/////////F置换////////////////////////////		  
      	   	    	for(cnt1 = 0; cnt1 < 32; cnt1++)			 
        				temp0[cnt1] = temp1[F_Table[cnt1]];   
    				for(cnt1 = 0; cnt1 < 32; cnt1++)
						temp1[cnt1]=temp0[cnt1];  	      
        			for(cnt1 = 0; cnt1 < 32; cnt1++)
        				Data_Bits[cnt1] ^= temp1[cnt1];  		//将明文左半部分与右半部分进行异或 
					///////////////左右移位	///////////////
					if(cnt0!=15)						
						{
							for(cnt1 = 0; cnt1 < 32; cnt1++)
								temp1[cnt1]=Data_Bits[cnt1];
							for(cnt1 = 0; cnt1 < 32; cnt1++)
								Data_Bits[cnt1]=Data_Bits[cnt1+32];
							for(cnt1 = 0; cnt1 < 32; cnt1++)
								Data_Bits[cnt1+32]=temp1[cnt1];
						}
						
					 
       	   		}  			   
	    	  //////////Init_1_Table置换//////////////////
			for(cnt0 = 0; cnt0< 64; cnt0++)
        		temp0[cnt0] = Data_Bits[Init_1_Table[cnt0]];
	  		for(cnt0=0;cnt0<64;cnt0++)
				Data_Bits[cnt0]=temp0[cnt0];	 		 							
			for(cnt0=0;cnt0<8;cnt0++)
				Data_Block[cnt0]=0;   
    		for(cnt0 = 0; cnt0 < 8; cnt0++)					   // 二进制数据流转换成字节
     	    		for(cnt1 = 0;cnt1 < 8; cnt1++)			   
       					Data_Block[cnt0] |=Data_Bits[(cnt0<<3)+cnt1]<<cnt1; 
            ES=1;
			SBUF=Data_Block[s_sf_cnt];
	     							
		 }
	}
	else
	{  	
		TI=0;
		s_sf_cnt++;
		if(s_sf_cnt==8)	 
			s_sf_cnt=0;
		else
           	SBUF=Data_Block[s_sf_cnt];
	
	 }
} 	 	 			  
//主函数 
void main(void)   
{  
	SCON=0XD0;
	TMOD=0X20;
	TH1=0XFD;
	TL1=0XFD;
	TR1=1;
	ES=1;
	EA=1;
	r_sf_cnt=0;
	s_sf_cnt=0;
	for(;;) {}
}