用脚本语言实现的des加密与解密(转载)

<script language="javascript">

// by liuminghua at 2005.1.10

var g_ip=new Array(   //初始置换ip
  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
);

var g_invip=new Array(  //逆初始置换ip
  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
);

var g_e=new Array(   //e 选位表
  32,1,2,3,4,5,4,5,6,7,8,9,8,9,10,11,12,13,12,13,14,15,16,17,16,17,18,19,20,21,20,21,22,23,24,25,24,25,26,27,28,29,28,29,30,31,32,31
);

var g_p=new Array(   //p 选位表
  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
);

var g_s=new Array(   //8个s合
  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,
  10,0,9,14,6,3,15,5,1,13,12,7,11,4,2,8,13,7,0,9,3,4,6,10,2,8,5,14,12,11,15,1,13,6,4,9,8,15,3,0,11,1,2,12,5,10,14,7,1,10,13,0,6,9,8,7,4,15,14,3,11,5,2,12,
  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      
);

var g_keyOut=new Array(768);

function InitKey(str_Key)
{
 var pc1=new Array(  //对64bit密钥进行置换为56位
   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 
 );
 var pc2=new Array(  //对经过移位得到的64bit选位得到48位密钥
   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
 );
 var nls=new Array(1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1);
  
 var b_array_key = new Array(64);
 for(n=i=0;i<8;i++)
  b_array_key[n++]=str_Key.charCodeAt(i)>>i&0x01;  //获得二进制
  
 var cd=new Array(56);
 var c=new Array(28);
 var d=new Array(28);
 
 for(i=0;i<56;i++)
  cd[i]=b_array_key[pc1[i]-1];
 for(i=0;i<28;i++){
  c[i]=cd[i];
  d[i]=cd[i+28];  //分离c,d
 }
 for(cnt=0;cnt<16;cnt++){
  for(i=0;i<nls[cnt];i++){
   c=lshift(c);
   d=lshift(d);
  }
  for(i=0;i<28;i++){
   cd[i]=c[i];
   cd[28+i]=d[i];
  }
  for(i=0;i<48;i++){
   g_keyOut[cnt*48+i]=cd[pc2[i]-1];
  }
 }
}
function lshift(p_Array)  //循环左移一位
{
 var tmp_Array=new Array(28);
 for(i=0;i<27;i++) tmp_Array[i]=p_Array[i+1];
 tmp_Array[27]=p_Array[0];
 return tmp_Array;
  
}

function frk(p_array_r,cnt)
{
 var b_array_fout=new Array(32);
 var b_array_expand=new Array(48);
 var array_pout=new Array(48);
 
 for(i=0;i<48;i++){  //将32位转换为48位
  b_array_expand[i]=p_array_r[g_e[i]-1];
 }
 var b_array_dor = new Array(48);
 for(i=0;i<48;i++){  //再与密钥ki按位异或,8组,每组6bit
  b_array_dor[i]= b_array_expand[i]^g_keyOut[cnt*48+i]; 
 }
 for(scnt=n=0;scnt<8;scnt++){
  row=(b_array_dor[scnt*6+0]<<1)+b_array_dor[scnt*6+5];
  col=(b_array_dor[scnt*6+1]<<3)+(b_array_dor[scnt*6+2]<<2)+(b_array_dor[scnt*6+3]<<1)+b_array_dor[scnt*6+4]
  var sout=new Array(8);
  sout[scnt]=g_s[scnt*64+(row<<4)+col];
  for(i=3;i>=0;i--){
   array_pout[n]=sout[scnt]>>i;
   sout[scnt]=sout[scnt]-(array_pout[n++]<<i);
  }
 }
 for(i=0;i<32;i++)
  b_array_fout[i]=array_pout[g_p[i]-1];
  
 return b_array_fout; 
}
function Des_EnCrypt(str_input)                    //加密
{
 // InitKey("454554454");   //only test , here
 
 var b_array_input = new Array(64);
 var b_array_lr = new Array(64);
 var b_array_l = new Array(32);
 var b_array_r = new Array(32);
 var b_array_fn = new Array(32);
 
 for(n=i=0;i<8;i++)
  for(j=0;j<8;j++)  
   b_array_input[n++]=str_input.charCodeAt(i)>>j&0x01;  //获得二进制  
 
 for(i=0;i<64;i++){
  b_array_lr[i]=b_array_input[g_ip[i]-1];
  if(i<32) b_array_l[i] =  b_array_lr[i];    
  else  b_array_r[i-32] = b_array_lr[i];   //分离l,r  
 }
 
 for(cnt=0;cnt<16;cnt++)
 {
  b_array_fn=frk(b_array_r,cnt);
  for(i=0;i<32;i++){
   j=b_array_r[i];
   b_array_r[i]=b_array_l[i]^b_array_fn[i];
   b_array_l[i]=j;
  }   
 }
 
 for(i=0;i<32;i++){
  b_array_lr[i]=b_array_r[i];
  b_array_lr[i+32]=b_array_l[i];
 }
 
 var fout=new Array(64); 
 for(i=0;i<64;i++) fout[i]=b_array_lr[g_invip[i]-1];
 var strout="";
 for(i=0;i<8;i++){
  sum=0; 
  for(j=0;j<8;j++){
   sum+=(fout[i*8+j]<<j);
  }
  strout+=String.fromCharCode(sum);
  //document.write(String.fromCharCode(sum)); 
 }
 
 return strout;
    
}
function Des_deCrypt(str_input)  //解密
{
 var b_array_input = new Array(64);
 var b_array_lr = new Array(64);
 var b_array_l = new Array(32);
 var b_array_r = new Array(32);
 var b_array_fn = new Array(32);
 
 for(n=i=0;i<8;i++)
  for(j=0;j<8;j++)  
   b_array_input[n++]=str_input.charCodeAt(i)>>j&0x01;  //获得二进制  
 
 for(i=0;i<64;i++){
  b_array_lr[i]=b_array_input[g_ip[i]-1];
  if(i<32) b_array_l[i] =  b_array_lr[i];    
  else  b_array_r[i-32] = b_array_lr[i];   //分离l,r  
 }
 
 for(cnt=15;cnt>=0;cnt--)
 {
  b_array_fn=frk(b_array_r,cnt);
  for(i=0;i<32;i++){
   j=b_array_r[i];
   b_array_r[i]=b_array_l[i]^b_array_fn[i];
   b_array_l[i]=j;
  }   
 }
 
 for(i=0;i<32;i++){
  b_array_lr[i]=b_array_r[i];
  b_array_lr[i+32]=b_array_l[i];
 }
 
 var fout=new Array(64); 
 for(i=0;i<64;i++) fout[i]=b_array_lr[g_invip[i]-1];
 var strout="";
 for(i=0;i<8;i++){
  sum=0; 
  for(j=0;j<8;j++){
   sum+=(fout[i*8+j]<<j);
  }
  strout+=String.fromCharCode(sum);
 }
 return strout;
}
</script>

posted on 2005-10-27 10:11  IORICC  阅读(460)  评论(0编辑  收藏  举报