des_me.java

有关于des的加解密算法的实现..是用java语言来编写的。.

/************************************************ 
DES 算法
*************************************************/ 

import java.lang.reflect.*; 
public class des_me { 
     /*static final是表示了只读，切能在同一个进程空间内的多个 
     Instance间共享*/ 
     private static String strDefaultKey = "87654321";
     public String digestHexStr; 
//28
     static final int pc_1_cp[]={
           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};//置换选择1的C0
//28
     static final int pc_1_dp[]={
           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};//置换选择1的D0
//48
     static final int pc_2p[]={
           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};//置换选择2
//16      
     static final int ls_countp[]={1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1};
//64      
     static final int iip_tab_p[]={
           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};//初始置换选择IP
//64
     static final int _iip_tab_p[]={
           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};//逆初始置换选择IP-1
//48
     static final int e_r_p[]={
           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};//选择运算E
//32
     static final int local_PP[]={
           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};//置换选择P
     //[8][4][16]
     static final int ccom_SSS_p[][][]={
           {{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}}, /* err on */

           {{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}, /* err on */
           {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}}};//代替函数组。。S1--S8
           
           
           
           
           
     byte[][] C=new byte[17][28];
     byte[][] D=new byte[17][28];
     byte[][] K=new byte[17][48];
     public des_me() { 
           return; 
     } 
     
     
     
     
     
     
     
     /*iu2b把int转换成byte
     */ 
     private static byte iu2b ( int input) { 
           byte output1;
           output1 = (byte)(input & 0xff); 
           return output1;
     } 
     
     
     
     
     

     /* 
     b2iu把byte按照不考虑正负号的原则的”升位”成int程序，
     因为java没有unsigned运算 
     */ 
     private static int b2iu(byte b) { 
           return b < 0 ? b & 0x7F + 128 : b; 
     } 







     /*byteHEX()，用来把一个byte类型的数转换成十六进制的ASCII表示， 
     　因为java中的byte的toString无法实现这一点，我们又没有C语言中的 
     sprintf(outbuf,"%02X",ib) 
     */ 
     public static String byteHEX(byte ib) { 
           char[] Digit = { '0','1','2','3','4','5','6','7','8','9', 'A','B','C','D','E','F' }; 
           char[] ob = new char[2]; 
           ob[0] = Digit[(ib >>> 4) & 0X0F]; 
           ob[1] = Digit[ib & 0X0F]; 
           String s = new String(ob); 
           return s; 
     } 
     
     
     
     
     
     /* desMemcpy是一个内部使用的byte数组的块拷贝函数，
           从input的inpos开始把len长度的 
           字节拷贝到output的outpos位置开始 
     */ 
     private void desMemcpy (byte[] output, byte[] input,      int outpos, int inpos, int len) { 
           int i; 
           for (i = 0; i < len; i++) 
                 output[outpos + i] = input[inpos + i]; 
     } 
     
     
     
     
     
     
     
     
     
     private void Fexpand0(byte[] in,byte[] out) {
           int divide;
           int i,j;
           byte temp1;

           for (i=0;i<8;i++)
           {
                 divide=7;
                 for (j=0;j<8;j++)
                 {
                       temp1=in;
                       out[8*i+j]=iu2b((b2iu(temp1)>>>divide)&1);
                       divide--;
                 }
           }
     }
     
     
     
     
     private void FLS(byte[] bits,byte[] buffer,int count) {
           int i,j;
           for (i=0;i<28;i++)
           {
                 buffer=bits[(i+count)%28];
           }
     }
     
     
     
     private void Fson(byte[] cc,byte[] dd,byte[] kk) {
           int i,j;
           byte[] buffer=new byte[56];
           for (i=0;i<28;i++)
                 buffer=cc;

           for (i=28;i<56;i++)
                 buffer=dd[i-28];

           for (i=0;i<48;i++)
                 kk=buffer[pc_2p-1];
     }
     private void Fsetkeystar(byte[] bits) {
           int i,j;

           for (i=0;i<28;i++)
                 C[0]=bits[pc_1_cp-1];
           for (i=0;i<28;i++)
                 D[0]=bits[pc_1_dp-1];
           for (j=0;j<16;j++)
           {
                 FLS(C[j],C[j+1],ls_countp[j]);
                 FLS(D[j],D[j+1],ls_countp[j]);
                 Fson(C[j+1],D[j+1],K[j+1]);
           }
     }
     private void Fiip(byte[] text,byte[] ll,byte[] rr) {
           int i,j;
           byte[] buffer=new byte[64];
           byte[] tmp=new byte[64];
           Fexpand0(text,buffer);

           for (i=0;i<32;i++)
                 ll=buffer[iip_tab_p-1];

           for (i=0;i<32;i++)
                 rr=buffer[iip_tab_p[i+32]-1];
     }
     private void Fs_box(byte[] aa,byte[] bb) {
           int i,j,k,m;
           int y,z;
           byte[] ss=new byte[8];
           m=0;
           for (i=0;i<8;i++)
           {
                 j=6*i;
                 y=b2iu(aa[j])*2+b2iu(aa[j+5]);
                 z=b2iu(aa[j+1])*8+b2iu(aa[j+2])*4+b2iu(aa[j+3])*2+b2iu(aa[j+4]);
                 ss=iu2b(ccom_SSS_p[y][z]);
                 y=3;
                 for (k=0;k<4;k++)
                 {
                       bb[m++]=iu2b((b2iu(ss)>>>y)&1);
                       y--;
                 }

           }
     }
     private void FF(int n,byte[] ll,byte[] rr,byte[] LL,byte[] RR) {
           int i,j;
           byte[] buffer=new byte[64],tmp=new byte[64];
           for (i=0;i<48;i++)
                 buffer=rr[e_r_p-1];
           for (i=0;i<48;i++)
                 buffer=iu2b((b2iu(buffer)+b2iu(K[n]))&1);

           Fs_box(buffer,tmp);

           for (i=0;i<32;i++)
                 buffer=tmp[local_PP-1];

           for (i=0;i<32;i++)
                 RR=iu2b((b2iu(buffer)+b2iu(ll))&1);

           for (i=0;i<32;i++)
                 LL=rr;
     }
     private void _Fiip(byte[] text,byte[] ll,byte[] rr) {
           int i,j;
           byte[] tmp=new byte[64];
           for (i=0;i<32;i++)
                 tmp=ll;
           for (i=32;i<64;i++)
                 tmp=rr[i-32];
           for (i=0;i<64;i++)
                 text=tmp[_iip_tab_p-1];
     }
     private void Fcompress016(byte[] out,byte[] in) {
           int times;
           int i,j;

           for (i=0;i<16;i++)
           {
                 times=3;
                 in='0';
                 for (j=0;j<4;j++)
                 {
                       in=iu2b(b2iu(in)+(b2iu(out[i*16+j])<<times));
                       times--;
                 }
           }
     }
     void Fcompress0(byte[] out,byte[] in) {
           int times;
           int i,j;

           for (i=0;i<8;i++)
           {
                 times=7;
                 in=0;
                 for (j=0;j<8;j++)
                 {
                       in=iu2b(b2iu(in)+(b2iu(out[i*8+j])<<times));
                       times--;
                 }
           }
     }
     private void Fencrypt0(byte[] text,byte[] mtext) {
           byte[] ll=new byte[64],rr=new byte[64],LL=new byte[64],RR=new byte[64];
           byte[] tmp=new byte[64];
           int i,j;
           Fiip(text,ll,rr);

           for (i=1;i<17;i++)
           {
                 FF(i,ll,rr,LL,RR);
                 for (j=0;j<32;j++)
                 {
                       ll[j]=LL[j];
                       rr[j]=RR[j];
                 }
           }

           _Fiip(tmp,rr,ll);

           Fcompress0(tmp,mtext);
     }
     private void FDES(byte[] key,byte[] text,byte[] mtext) {
           byte[] tmp=new byte[64];
           Fexpand0(key,tmp);
           Fsetkeystar(tmp);
           Fencrypt0(text,mtext);
     }
     
     
     
     
     
     
     

     /*加密*/
     public int ENCRYPT(byte[] key, byte[] s,byte[] d,int len ) {
           int i,j;
           byte[] cData=new byte[8];
           byte[] cEncryptData=new byte[8];
           for (i=0;i<len;i+=8) {
                 if ((i+8)>len) {
                       desMemcpy(cData,s,0,i,len-i);
                       for (j = len-i; j < 8; j++) 
                             cData[j] = 0; 
                 } else
                       desMemcpy(cData,s,0,i,8);
                 FDES(key,cData,cEncryptData);
                 desMemcpy(d,cEncryptData,i,0,8);

           }
           return i;
     }
     private void Fdiscrypt0(byte[] mtext,byte[] text) {
           byte[] ll=new byte[64],rr=new byte[64],LL=new byte[64],RR=new byte[64];
           byte[] tmp=new byte[64];
           int i,j;
           Fiip(mtext,ll,rr);

           for (i=16;i>0;i--)
           {
                 FF(i,ll,rr,LL,RR);
                 for (j=0;j<32;j++)
                 {
                       ll[j]=LL[j];
                       rr[j]=RR[j];
                 }
           }

           _Fiip(tmp,rr,ll);

           Fcompress0(tmp,text);
     }
     /*****************************************************************************
     * function:      DES
     * parameter:      u_char * key      ; key for encrypt
     *            u_char * mtext      ; encipher data 
     *            u_char * text      ; plain data
     * return:      none
     *****************************************************************************/
     private void _FDES(byte[] key,byte[] mtext,byte[] text) {
           byte[] tmp=new byte[64];
           Fexpand0(key,tmp);
           Fsetkeystar(tmp);
           Fdiscrypt0(mtext,text);
     }
     /*解密*/
     public int DECRYPT(byte[] key, byte[] s,byte[] d,int len ) {
           int i;
           byte[] cData=new byte[8];
           byte[] cEncryptData=new byte[8];
           for(i=0;i<len;i+=8) {
                 desMemcpy(cEncryptData,d,0,i,8);
                 _FDES(key,cEncryptData,cData);
                 desMemcpy(s,cData,i,0,8);
           }
           return i;
     }
     public static byte[] hexStr2ByteArr(String strIn) {
           byte[] arrB = strIn.getBytes();
           int iLen = arrB.length;

           //两个字符表示一个字节，所以字节数组长度是字符串长度除以2
           byte[] arrOut = new byte[iLen / 2];
           for (int i = 0; i < iLen; i = i + 2) {
                 String strTmp = new String(arrB, i, 2);
                 arrOut[i / 2] = (byte) Integer.parseInt(strTmp, 16);
           }
           return arrOut;
     }
     public static void main(String args[]) { 
           int i1,i2;
           des_me m = new des_me(); 
           String digestHexStr;
           //String str=new String("1111");
           String str=new String("速度飞洒答1111aaaa$%^&复洒");
           byte[] byte2=new byte[3000];
           byte[] byte1=str.getBytes(); 
           byte[] byteMingW=new byte[3000]; //密文
           byte[] byteMiW=new byte[3000];
           i1=m.ENCRYPT(m.strDefaultKey.getBytes(),byte1,byte2,byte1.length);
           digestHexStr = ""; 
           for (int i = 0; i < i1; i++) { 
                 digestHexStr += byteHEX(byte2); 
           } 
           System.out.println("密文:["+digestHexStr+"]");

           byteMiW=m.hexStr2ByteArr(digestHexStr);
           i2=m.DECRYPT(m.strDefaultKey.getBytes(),byteMingW,byteMiW,byteMiW.length);
           System.out.println("明文:["+new String(byteMingW,0,i2)+"]");
     } 
}