des加密字符串c语言

A. 用c语言写des加密算法

#include <stdio.h> #include <string.h> #include <windows.h> #include <conio.h> #include "Schedle.h" class CShift{ public: DWORDLONG mask[16]; int step[16]; CShift(){ for(int i=0;i<16;i++){ step[i]=2; mask[i]=0xc000000; } step[0]=step[1]=step[8]=step[15]=1; mask[0]=mask[1]=mask[8]=mask[15]=0x8000000; } }; class CDES{ public: CDES(){ m_dwlKey=0; m_dwlData=0; ConvertTableToMask(dwlKey_PC_1,64); //PrintTable(dwlKey_PC_1,7,8); ConvertTableToMask(dwlKey_PC_2,56); ConvertTableToMask(dwlData_IP,64); ConvertTableToMask(dwlData_Expansion,32); ConvertTableToMask(dwlData_FP,64); ConvertTableToMask(dwlData_P,32); Generate_S(); } void PrintBit(DWORDLONG); void EncryptKey(char *); unsigned char* EncryptData(unsigned char *); unsigned char* DescryptData(unsigned char*); private: void ConvertTableToMask(DWORDLONG *,int); void Generate_S(void); void PrintTable(DWORDLONG*,int,int); DWORDLONG ProcessByte(unsigned char*,BOOL); DWORDLONG PermuteTable(DWORDLONG,DWORDLONG*,int); void Generate_K(void); void EncryptKernel(void); DWORDLONG Generate_B(DWORDLONG,DWORDLONG*); /*For verify schele permutation only*/ DWORDLONG UnPermuteTable(DWORDLONG,DWORDLONG*,int); /**************************************/ DWORDLONG dwlData_S[9][4][16]; CShift m_shift; DWORDLONG m_dwlKey; DWORDLONG m_dwlData; DWORDLONG m_dwl_K[17]; }; void CDES::EncryptKey(char *key){ printf("\nOriginal Key: %s",key); m_dwlKey=ProcessByte((unsigned char*)key,TRUE); // PrintBit(m_dwlKey); m_dwlKey=PermuteTable(m_dwlKey,dwlKey_PC_1,56); // PrintBit(m_dwlKey); Generate_K(); // printf("\n******************************************\n"); } void CDES::Generate_K(void){ DWORDLONG C[17],D[17],tmp; C[0]=m_dwlKey>>28; D[0]=m_dwlKey&0xfffffff; for(int i=1;i<=16;i++){ tmp=(C[i-1]&m_shift.mask[i-1])>>(28-m_shift.step[i-1]); C[i]=((C[i-1]<<m_shift.step[i-1])|tmp)&0x0fffffff; tmp=(D[i-1]&m_shift.mask[i-1])>>(28-m_shift.step[i-1]); D[i]=((D[i-1]<<m_shift.step[i-1])|tmp)&0x0fffffff; m_dwl_K[i]=(C[i]<<28)|D[i]; m_dwl_K[i]=PermuteTable(m_dwl_K[i],dwlKey_PC_2,48); } } DWORDLONG CDES::ProcessByte(unsigned char *key,BOOL shift){ unsigned char tmp; DWORDLONG byte=0; int i=0; while(i<8){ while(*key){ if(byte!=0) byte<<=8; tmp=*key; if(shift) tmp<<=1; byte|=tmp; i++; key++; } if(i<8) byte<<=8; i++; } return byte; } DWORDLONG CDES::PermuteTable(DWORDLONG dwlPara,DWOR 基于des算法的rfid安全系统
DLONG* dwlTable,int nDestLen){ int i=0; DWORDLONG tmp=0,moveBit; while(i<nDestLen){ moveBit=1; if(dwlTable[i]&dwlPara){ moveBit<<=nDestLen-i-1; tmp|=moveBit; } i++; } return tmp; } DWORDLONG CDES::UnPermuteTable(DWORDLONG dwlPara,DWORDLONG* dwlTable,int nDestLen){ DWORDLONG tmp=0; int i=nDestLen-1; while(dwlPara!=0){ if(dwlPara&0x01) tmp|=dwlTable[i]; dwlPara>>=1; i--; } return tmp; } void CDES::PrintTable(DWORDLONG *dwlPara,int col,int row){ int i,j; for(i=0;i<row;i++){ printf("\n"); getch(); for(j=0;j<col;j++) PrintBit(dwlPara[i*col+j]); } } void CDES::PrintBit(DWORDLONG bitstream){ char out[76]; int i=0,j=0,space=0; while(bitstream!=0){ if(bitstream&0x01) out[i++]='1'; else out[i++]='0'; j++; if(j%8==0){ out[i++]=' '; space++; } bitstream=bitstream>>1; } out[i]='\0'; strcpy(out,strrev(out)); printf("%s **:%d\n",out,i-space); } void CDES::ConvertTableToMask(DWORDLONG *mask,int max){ int i=0; DWORDLONG nBit=1; while(mask[i]!=0){ nBit=1; nBit<<=max-mask[i]; mask[i++]=nBit; } } void CDES::Generate_S(void){ int i; int j,m,n; m=n=0; j=1; for(i=0;i<512;i++){ dwlData_S[j][m][n]=OS[i]; n=(n+1)%16; if(!n){ m=(m+1)%4; if(!m) j++; } } } unsigned char * CDES::EncryptData(unsigned char *block){ unsigned char *EncrytedData=new unsigned char(15); printf("\nOriginal Data: %s\n",block); m_dwlData=ProcessByte(block,0); // PrintBit(m_dwlData); m_dwlData=PermuteTable(m_dwlData,dwlData_IP,64); EncryptKernel(); // PrintBit(m_dwlData); DWORDLONG bit6=m_dwlData; for(int i=0;i<11;i++){ EncrytedData[7-i]=(unsigned char)(bit6&0x3f)+46; bit6>>=6; } EncrytedData[11]='\0'; printf("\nAfter Encrypted: %s",EncrytedData); for(i=0;i<8;i++){ EncrytedData[7-i]=(unsigned char)(m_dwlData&0xff); m_dwlData>>=8; } EncrytedData[8]='\0'; return EncrytedData; } void CDES::EncryptKernel(void){ int i=1; DWORDLONG L[17],R[17],B[9],EK,PSB; L[0]=m_dwlData>>32; R[0]=m_dwlData&0xffffffff; for(i=1;i<=16;i++){ L[i]=R[i-1]; R[i-1]=PermuteTable(R[i-1],dwlData_Expansion,48); //Expansion R EK=R[i-1]^m_dwl_K[i]; //E Permutation PSB=Generate_B(EK,B); //P Permutation R[i]=L[i-1]^PSB; } R[16]<<=32; m_dwlData=R[16]|L[16]; m_dwlData=PermuteTable(m_dwlData,dwlData_FP,64); } unsigned char* CDES::DescryptData(unsigned char *desData){ int i=1; unsigned char *DescryptedData=new unsigned char(15); DWORDLONG L[17],R[17],B[9],EK,PSB; DWORDLONG dataPara; dataPara=ProcessByte(desData,0); dataPara=PermuteTable(dataPara,dwlData_IP,64); R[16]=dataPara>>32; L[16]=dataPara&0xffffffff; for(i=16;i>=1;i--){ R[i-1]=L[i]; L[i]=PermuteTable(L[i],dwlData_Expansion,48); //Expansion L EK=L[i]^m_dwl_K[i]; //E Permutation PSB=Generate_B(EK,B); //P Permutation L[i-1]=R[i]^PSB; } L[0]<<=32; dataPara=L[0]|R[0]; dataPara=PermuteTable(dataPara,dwlData_FP,64); // PrintBit(dataPara); for(i=0;i<8;i++){ DescryptedData[7-i]=(unsigned char)(dataPara&0xff); dataPara>>=8; } DescryptedData[8]='\0'; printf("\nAfter Decrypted: %s\n",DescryptedData); return DescryptedData; } DWORDLONG CDES::Generate_B(DWORDLONG EKPara,DWORDLONG *block){ int i,m,n; DWORDLONG tmp=0; for(i=8;i>0;i--){ block[i]=EKPara&0x3f; m=(int)(block[i]&0x20)>>4; m|=block[i]&0x01; n=(int)(block[i]<<1)>>2; block[i]=dwlData_S[i][m][n]; EKPara>>=6; } for(i=1;i<=8;i++){ tmp|=block[i]; tmp<<=4; } tmp>>=4; tmp=PermuteTable(tmp,dwlData_P,32); return tmp; } void main(void){ CDES des; des.EncryptKey("12345678"); unsigned char *result=des.EncryptData((unsigned char*)"DemoData"); des.DescryptData(result); }[1]

B. 用C语言实现DES加密算法！

l iceEncryptText 文本加密解密
http://dl.icese.net/src.php?f=iceEncryptText.src.rar

C. DES加密算法C语言实现

/*********************************************************************/
/*-文件名：des.h */
/*- */
/*-功能： 实现DES加密算法的加密解密功能 */
/*********************************************************************/
typedef int INT32;
typedef char INT8;
typedef unsigned char ULONG8;
typedef unsigned short ULONG16;
typedef unsigned long ULONG32;

/*如果采用c++编译器的话采用如下宏定义
#define DllExport extern "C" __declspec(dllexport)
*/

#define DllExport __declspec(dllexport)

/*加密接口函数*/
DllExport INT32 DdesN(ULONG8 *data, ULONG8 **key, ULONG32 n_key,ULONG32 readlen);
DllExport INT32 desN(ULONG8 *data, ULONG8 **key, ULONG32 n_key,ULONG32 readlen);
DllExport INT32 des3(ULONG8 *data, ULONG8 *key,ULONG32 n ,ULONG32 readlen);
DllExport INT32 Ddes3(ULONG8 *data,ULONG8 *key,ULONG32 n ,ULONG32 readlen);
DllExport INT32 des(ULONG8 *data, ULONG8 *key,INT32 readlen);
DllExport INT32 Ddes(ULONG8 *data,ULONG8 *key,INT32 readlen);

*********************************************************************/
/*-文件名：des.c */
/*- */
/*-功能： 实现DES加密算法的加密解密功能 */
//*********************************************************************/
＃include <stdlib.h>
＃include <stdio.h>
＃include <string.h>
＃include <memory.h>
＃include <malloc.h>
＃include "des.h"

#define SUCCESS 0
#define FAIL -1

#define READFILESIZE 512

#define WZ_COMMEND_NUM 4
#define WZUSEHELPNUM 19
#define DESONE 1
#define DESTHREE 2
#define DESMULTI 3
INT8 *WZ_Commend_Help[] =
{

"基于DES的加密解密工具v1.0 ",/*0*/
"追求卓越,勇于创新 ",
"----着者 : 吴真--- ",
" "
};

INT8 *WZ_USE_HELP[]={
"输入5+n个参数:",
"\t1.可执行文件名 *.exe",
"\t2.操作类型 1:一层加密;2:一层解密;",
"\t\t13:N层单密钥加密;23:N层单密钥解密;",
"\t\t39:N层多密钥加密;49:N层多密钥解密",
"\t3.读出数据的文件名*.txt",
"\t4.写入数据的文件名*.txt",
"\t5.密钥(8字节例如:wuzhen12)",
"\t[6].N层单密钥的层数或者...二层加密|解密密钥",
"\t[7].三层加密|解密密钥",
"\t[8]. ...",
"\t[N].N层加密|解密密钥",
"\t 例1: des 1 1.txt 2.txt 12345678",
"\t : des 2 2.txt 3.txt 12345678",
"\t 例2: des 13 1.txt 2.txt tiantian 5",
"\t : des 23 2.txt 3.txt tiantian 5",
"\t 例3: des 39 1.txt 2.txt 12345678 tiantian gaoxinma",
"\t : des 49 2.txt 3.txt 12345678 tiantian gaoxinma",
"******************************"
};

INT32 hextofile( ULONG8 *buf ,FILE *writefile, ULONG32 length);/*以16进制写入文件*/
INT32 encodehex(ULONG8 *tobuf,ULONG8 *frombuf,ULONG32 len);/*16进制解码*/

INT32 file_enc(FILE *readfile,FILE *writefile,
ULONG8 *key,ULONG32 keynum,
ULONG8 **superkey,ULONG32 n_superkey,
ULONG8 flag);
INT32 file_dec(FILE *readfile,FILE *writefile,
ULONG8 *key,ULONG32 keynum,
ULONG8 **superkey,ULONG32 n_superkey,
ULONG8 flag);
void wz_print_help();

INT32 main(INT32 argc,INT8 *argv[])
{
INT8 *FILENAME1,*FILENAME2;
FILE *fp, *fp2;
ULONG8 *key ;
ULONG8 **superkey ;/*n层加密解密密钥*/
ULONG8 n_superkey ;
ULONG32 num;

if ( argc >= 5 && (atoi(argv[1]) == 39 || atoi(argv[1]) == 49 ) )
{
n_superkey = argc - 4 ;
superkey = ( INT8 **)calloc(1, n_superkey*sizeof( void *) ) ;
for ( num = 0 ; num < n_superkey ; num++)
{
superkey[num] = argv[4+num] ;
}

}
else if ( argc == 6 && (atoi(argv[1]) == 13 || atoi(argv[1]) == 23 ) && (atoi(argv[5])) > 0)
{

}
else if ( argc == 5 && ( atoi(argv[1]) == 1 || atoi(argv[1]) == 2 ))
{

}
else
{
wz_print_help();
return FAIL;
}
FILENAME1 = argv[2];
FILENAME2 = argv[3];
if ((fp= fopen(FILENAME1,"rb")) == NULL || (fp2 = fopen(FILENAME2,"wb"))==NULL)
{

printf("Can't open file\n");
return FAIL;
}

key = argv[4] ;
switch( atoi(argv[1] ))
{
case 1: /*加密*/
file_enc(fp,fp2,key,0, NULL,0, DESONE);
printf("\n \tDES 一层加密完毕,密文存于%s文件\n",FILENAME2);
break;
case 2:
file_dec(fp,fp2,key,0, NULL, 0,DESONE);
printf("\n \tDES 一层解密完毕,密文存于%s文件\n",FILENAME2);
break;
case 13:
file_enc(fp,fp2,key,atoi(argv[5]),NULL,0,DESTHREE);
printf("\n \tDES %u层单密钥加密完毕,密文存于%s文件\n",atoi(argv[5]),FILENAME2);
break;
case 23:
file_dec(fp,fp2,key,atoi(argv[5]),NULL,0,DESTHREE);
printf("\n \tDES %u层单密钥解密完毕,密文存于%s文件\n",atoi(argv[5]),FILENAME2);
break;
case 39:
file_enc(fp,fp2,NULL,0,superkey,n_superkey,DESMULTI);
printf("\n \tDES 多密钥加密完毕,密文存于%s文件\n",FILENAME2);
free(superkey);
superkey = NULL;
break;
case 49:
file_dec(fp,fp2,NULL,0,superkey,n_superkey,DESMULTI);
printf("\n \tDES 多密钥加密完毕,密文存于%s文件\n",FILENAME2);
free(superkey);
superkey = NULL;
break;
default:
printf("请选择是加密|解密 plese choose encrypt|deencrypt\n");
break;
}

fclose(fp);
fclose(fp2);
return SUCCESS;

}

void wz_print_help()
{
INT32 i ;
printf("\t");
for ( i = 0 ; i < 22 ; i++)
{
printf("%c ",5);
}
printf("\n");
for( i = 0 ; i < WZ_COMMEND_NUM ; i++)
{
printf("\t%c\t%s %c\n",5,WZ_Commend_Help[i],5);
}
printf("\t");
for ( i = 0 ; i < 22 ; i++)
{
printf("%c ",5);
}
printf("\n");
for( i = 0 ; i < WZUSEHELPNUM ; i++)
{
printf("\t%s\n",WZ_USE_HELP[i]);
}
return ;
}

INT32 file_enc(FILE *readfile,FILE *writefile,
ULONG8 *key,ULONG32 keynum,
ULONG8 **superkey,ULONG32 n_superkey,
ULONG8 flag)
{
INT32 filelen = 0,readlen = 0,writelen = 0;
ULONG32 totalfilelen = 0 ;/*统计实际的文件的长度*/
ULONG8 readbuf[READFILESIZE] = { 0 };
filelen = fread( readbuf, sizeof( INT8 ), READFILESIZE, readfile );
while( filelen == READFILESIZE )
{
totalfilelen += READFILESIZE;
switch(flag)
{
case DESONE:
des( readbuf,key,READFILESIZE);
break;
case DESTHREE:
des3( readbuf, key ,keynum,READFILESIZE);
break;
case DESMULTI:
desN( readbuf, superkey ,n_superkey,READFILESIZE);
break;
}
hextofile( readbuf, writefile, READFILESIZE );/*以16进制形式写入文件*/
memset(readbuf,0,READFILESIZE);
filelen = fread( readbuf, sizeof( INT8 ), READFILESIZE, readfile );
}
/*这是从文件中读出的最后一批数据,长度可能会等于0,所以要先判断*/

if ( filelen > 0 )
{
/*如果从文件中读出的长度不等于0,那么肯定有8个字节以上的空间
文件长度存在最后8个字节中*/
totalfilelen += filelen;
memcpy( &readbuf[READFILESIZE-8], (ULONG8*)&totalfilelen,4);
switch(flag)
{
case DESONE:
des( readbuf,key,READFILESIZE);
break;
case DESTHREE:
des3( readbuf, key ,keynum,READFILESIZE);
break;
case DESMULTI:
desN( readbuf, superkey ,n_superkey,READFILESIZE);
break;
}
hextofile( readbuf, writefile,READFILESIZE );/*以16进制形式写入文件*/
memset(readbuf,0 ,READFILESIZE);
}
else /*filelen == 0*/
{
memcpy( &readbuf[0], (ULONG8*)&totalfilelen,4);
switch(flag)
{
case DESONE:
des( readbuf,key,8);
break;
case DESTHREE:
des3( readbuf, key ,keynum,8);
break;
case DESMULTI:
desN( readbuf, superkey ,n_superkey,8);
break;
}
hextofile( readbuf, writefile, 8);/*以16进制形式写入文件*/
}
return SUCCESS;
}

INT32 file_dec(FILE *readfile,FILE *writefile,
ULONG8 *key,ULONG32 keynum,
ULONG8 **superkey,ULONG32 n_superkey,
ULONG8 flag)
{
INT32 filelen = 0,readlen = 0,writelen = 0;
ULONG32 totalfilelen = 0 ;/*统计实际的文件的长度*/
INT32 num = 0;
ULONG8 readbuf[READFILESIZE] = { 0 };
ULONG8 sendbuf[READFILESIZE*2] = { 0 };

fseek(readfile,-16,SEEK_END);/*最后16个字节的表示文件长度的空间*/
filelen = fread( sendbuf, sizeof( INT8 ), 16, readfile );
encodehex( readbuf,sendbuf,8);
switch(flag)
{
case DESONE:
Ddes( readbuf,key,8);
break;
case DESTHREE:
Ddes3( readbuf, key ,keynum,8);
break;
case DESMULTI:
DdesN( readbuf, superkey ,n_superkey,8);
break;
}
/*解密*/
memcpy((ULONG8*)&totalfilelen, &readbuf[0],4);/*得到文件总长*/
memset(readbuf,0 ,8);
memset(sendbuf,0 ,16);

num = totalfilelen/READFILESIZE;/*有几个READFILESIZE组*/
totalfilelen %= READFILESIZE;

fseek(readfile,0,SEEK_SET);/*跳到文件头*/
while(num--)
{
filelen = fread( sendbuf, sizeof( INT8 ), READFILESIZE*2, readfile );
encodehex( readbuf,sendbuf,READFILESIZE);
switch(flag)
{
case DESONE:
Ddes( readbuf,key,READFILESIZE);
break;
case DESTHREE:
Ddes3( readbuf, key ,keynum,READFILESIZE);
break;
case DESMULTI:
DdesN( readbuf, superkey ,n_superkey,READFILESIZE);
break;
}

writelen = fwrite(readbuf, sizeof( INT8 ), READFILESIZE, writefile);
memset(readbuf,0 ,READFILESIZE);
memset(sendbuf,0 ,READFILESIZE*2);
}
if ( totalfilelen > 0 )/*最后一块有多余的元素*/
{
filelen = fread( sendbuf, sizeof( INT8 ), READFILESIZE*2, readfile );
encodehex( readbuf,sendbuf,READFILESIZE);
switch(flag)
{
case DESONE:
Ddes( readbuf,key,READFILESIZE);
break;
case DESTHREE:
Ddes3( readbuf, key ,keynum,READFILESIZE);
break;
case DESMULTI:
DdesN( readbuf, superkey ,n_superkey,READFILESIZE);
break;
}
writelen = fwrite(readbuf, sizeof( INT8 ), totalfilelen, writefile);
memset(readbuf,0 ,READFILESIZE);
memset(sendbuf,0 ,READFILESIZE*2);

}
return SUCCESS;
}

INT32 hextofile( ULONG8 *buf ,FILE *writefile, ULONG32 length)
{
ULONG32 writelen = 0 ;
/*以16进制形式写入文件*/
while( writelen < length)
{
if(buf[writelen] == 0)
{
fprintf( writefile, "%x", 0 );
fprintf( writefile, "%x", 0 );
}
else if (buf[writelen] < 0x10)
{
fprintf( writefile, "%x", 0 );
fprintf( writefile, "%x", buf[writelen] );
}
else
{
fprintf( writefile, "%x", buf[writelen] );

}
writelen++;

}
return SUCCESS;
}
INT32 encodehex(ULONG8 *tobuf,ULONG8 *frombuf,ULONG32 len)
{
ULONG8 *readfirst = frombuf ;
ULONG8 *readend = &frombuf[1] ;
INT8 *s;
ULONG8 y[2] ;
ULONG32 i;
for ( i = 0 ; i < len ; i++)
{
y[0] = *readfirst ;
y[1] = *readend ;
readfirst += 2 ;
readend += 2 ;
tobuf[i] = (ULONG8)strtol((INT8*)y, &s, 16);
}
return SUCCESS;
}

D. c语言DES加密信息得到密文，java语言解密这段密文。

只要算法和密钥相同，必然可以解密成功

E. 如何实现C语言的DES加密算法实现，请关注

可能很长 ，这是在我以前一个程序里摘出来的。 原理：用户输入创建密码，机器读取，并把每一位密码进行加密，这里就是把每一位的 ASCII码加一（也可以有其他的加密方式），然后保存在文件里。解密时从文件中读取保存的乱码，然后把它每一位的asc

F. 急！急！急求des加密解密算法，用c语言编写的（最迟到明晚），谢谢！！！

#include "stdafx.h"

#include < bitset >
#include < vector >
#include < string >
#include < iostream >

using namespace std;
//using namespace gy;

typedef bitset< 4 > _b4;
typedef bitset< 6 > _b6;
typedef bitset< 8 > _b8;
typedef bitset< 28 > _b28;
typedef bitset< 32 > _b32;
typedef bitset< 48 > _b48;
typedef bitset< 56 > _b56;
typedef bitset< 64 > _b64;

typedef vector< _b8 > _vb8;
typedef vector< _b48 > _vb48;
typedef vector< _b64 > _vb64;

namespace {

const unsigned char odd_parity[256]={
1, 1, 2, 2, 4, 4, 7, 7, 8, 8, 11, 11, 13, 13, 14, 14,
16, 16, 19, 19, 21, 21, 22, 22, 25, 25, 26, 26, 28, 28, 31, 31,
32, 32, 35, 35, 37, 37, 38, 38, 41, 41, 42, 42, 44, 44, 47, 47,
49, 49, 50, 50, 52, 52, 55, 55, 56, 56, 59, 59, 61, 61, 62, 62,
64, 64, 67, 67, 69, 69, 70, 70, 73, 73, 74, 74, 76, 76, 79, 79,
81, 81, 82, 82, 84, 84, 87, 87, 88, 88, 91, 91, 93, 93, 94, 94,
97, 97, 98, 98,100,100,103,103,104,104,107,107,109,109,110,110,
112,112,115,115,117,117,118,118,121,121,122,122,124,124,127,127,
128,128,131,131,133,133,134,134,137,137,138,138,140,140,143,143,
145,145,146,146,148,148,151,151,152,152,155,155,157,157,158,158,
161,161,162,162,164,164,167,167,168,168,171,171,173,173,174,174,
176,176,179,179,181,181,182,182,185,185,186,186,188,188,191,191,
193,193,194,194,196,196,199,199,200,200,203,203,205,205,206,206,
208,208,211,211,213,213,214,214,217,217,218,218,220,220,223,223,
224,224,227,227,229,229,230,230,233,233,234,234,236,236,239,239,
241,241,242,242,244,244,247,247,248,248,251,251,253,253,254,254
};

const int keyperm_table56[56] = {
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
};

const int keycompperm_table[48] = {
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
};

const int keyshift_table[16] = {
1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1
};

const int datainitperm_table[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
};

const int dataexpperm_table[48] = {
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
};

const int datasbox_table[8][4][16] = {
{
{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},
}
};

const int datapperm_table[32] = {
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
};

const int datafp_table[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
};

template < size_t _NB >
void rotateleft_bitset(bitset< _NB >& input, size_t step)
{
bitset< _NB > tmp = input;
input <<= step;
tmp >>= _NB - step;
input |= tmp;
}

template < size_t _NB >
void rotateright_bitset(bitset< _NB >& input, size_t step)
{
bitset< _NB > tmp = input;
input >>= step;
tmp <<= _NB - step;
input |= tmp;
}

template < class Input, class Output, class Table>
void Des_Permutation( const Input& input, Output& output, const Table& table, size_t TableSize)
{
for (size_t i = 0; i < TableSize; ++i) {
output[i] = input[ table[i]-1 ];
}
}

void Des_Key_Permutation1(const _b64& input, _b56& output)
{
Des_Permutation(input, output, keyperm_table56, sizeof(keyperm_table56)/sizeof(int));
}

void Des_Key_CompPerm(const _b56& input, _b48& output)
{
Des_Permutation(input, output, keycompperm_table, sizeof(keycompperm_table)/sizeof(int));
}

void Des_Key_Shift(_b56& key56, size_t step)
{
_b28 l28, r28;
int i;
for (i = 0; i < 28; ++i) {
r28[i] = key56[i];
l28[i] = key56[28+i];
}
rotateleft_bitset(l28, step);
rotateleft_bitset(r28, step);
for (i = 0; i < 28; ++i) {
key56[i] = r28[i];
key56[28+i] = l28[i];
}
}

void Des_Key_Generate(const _b64& key, _vb48& subkey)
{
_b56 tmp56;
Des_Key_Permutation1(key, tmp56);

for (int i = 0; i < 16; ++i) {
_b48 tmp48;
Des_Key_Shift(tmp56, keyshift_table[i]);
Des_Key_CompPerm(tmp56, tmp48);
cout << "Key: " << tmp48 << endl;
subkey.push_back(tmp48);
}
}

void Des_Char_To_Binary(char c, string& binary)
{
unsigned char tmp = odd_parity[c];
binary.append( (tmp & 0x80) ? "1" : "0" );
binary.append( (tmp & 0x40) ? "1" : "0" );
binary.append( (tmp & 0x20) ? "1" : "0" );
binary.append( (tmp & 0x10) ? "1" : "0" );
binary.append( (tmp & 0x08) ? "1" : "0" );
binary.append( (tmp & 0x04) ? "1" : "0" );
binary.append( (tmp & 0x02) ? "1" : "0" );
binary.append( (tmp & 0x01) ? "1" : "0" );
}

void Des_String_To_Binary(const string& input, _b64& output)
{
string binary;
for (int i = 0; i < input.length(); ++i ) {
Des_Char_To_Binary(input[i], binary);
}
_b64 tmp64(binary);
output = tmp64;
}

void Des_String_To_Key(const string& key, _vb48& subkey)
{
_b64 tmp64;
Des_String_To_Binary(key, tmp64);
Des_Key_Generate(tmp64, subkey);
}

void Des_Data_ExpPerm(const _b32& input, _b48& output)
{
Des_Permutation(input, output, dataexpperm_table, sizeof(dataexpperm_table)/sizeof(int));
}

void Des_Data_IP(const _b64& input, _b64& output)
{
Des_Permutation(input, output, datainitperm_table, sizeof(datainitperm_table)/sizeof(int));
}

void Des_Data_S(const _b6& input, _b4& output, int step)
{
bitset< 2 > tmp2;
_b4 tmp4;
tmp2[0] = input[5];
tmp2[1] = input[0];
tmp4[0] = input[1];
tmp4[1] = input[2];
tmp4[2] = input[3];
tmp4[3] = input[4];
_b8 t8(datasbox_table[step][tmp2.to_ulong()][tmp4.to_ulong()]);
for (int i = 0; i < 4; ++i) {
output[i] = t8[i];
}
}

void Des_Data_S(const _b48& input, _b32& output)
{
_b6 tmp6;
_b4 tmp4;
int i, j;
for (i = 0; i < 8; ++i) {
for (j = 6; j < 0; --j) {
tmp6[j] = input[ 47 - i*6 - j];
}
Des_Data_S(tmp6, tmp4, i);
for (j = 0; j < 4; ++j) {
output[ 31 - (i << 2) - j] = tmp4[j];
}
}
}

void Des_Data_P(const _b32& input, _b32& output)
{
Des_Permutation(input, output, datapperm_table, sizeof(datapperm_table)/sizeof(int));
}

void Des_Data_F(_b64& input, const _b48& key)
{
_b32 l32, r32, tmp32, t32;
_b48 exp48;
int i;
for (i = 0; i < 32; ++i ) {
r32[i] = input[i];
l32[i] = input[32+i];
}
//cout << "r32** " << r32 << endl;
Des_Data_ExpPerm(r32, exp48);
//cout << "exp** " << exp48 << endl;
//cout << "key** " << key << endl;
exp48 ^= key;
//cout << "exp** " << exp48 << endl;
Des_Data_S(exp48, tmp32);
//cout << "tmp** " << tmp32 << endl;
Des_Data_P(tmp32, t32);
//cout << "t32** " << t32 << endl;
t32 ^= l32;
l32 = r32;
r32 = t32;
for (i = 0; i < 32; ++i ) {
input[i] = r32[i];
input[32+i] = l32[i];
}
}

void Des_data_FP(const _b64& input, _b64& output)
{
Des_Permutation(input, output, datafp_table, sizeof(datafp_table)/sizeof(int));
}

int Des_encode_64bit(const _vb48& key, const _b64 &data, _b64 &output)
{
_b64 tmp64;

Des_Data_IP(data, tmp64);
for (int i = 0; i < 16; ++i) {
//cout << " " << tmp64 << endl;
Des_Data_F(tmp64, key[i]);
//cout << " " << tmp64 << endl;
}
Des_data_FP(tmp64, output);
return 0;
}

int Des_encode(const string& key, const string& data, _b64 &output)
{
_vb48 subkey, decodekey;
_b64 data64, tmp64;

Des_String_To_Key(key, subkey);

for (int i = 0; i < 16; ++i) {
decodekey.push_back(subkey[ 15-i ]);
}

Des_String_To_Binary(data, data64);

//cout << "data: " << data64 << endl;

Des_encode_64bit(subkey, data64, output);
//cout << "code: " << output << endl;
Des_encode_64bit(decodekey, output, tmp64);
//cout << "reco: " << tmp64 << endl;
if (tmp64 == data64) {
cout << "Congratulation.$$$$$$$$$$$$$$$$$$$$$$$" << endl;
}else {
cout << "Error. **************************" << endl;
}

return 0;
}

int Des_decode(const string& key, const string& data, _b64 &output)
{
return 0;
}
}

namespace gy {

/* Mode: true for encode, false for decode */
int Des(const string& key, const string& data, _b64 &output, bool Mode)
{
if (Mode) {
return Des_encode(key, data, output);
}else {
return Des_decode(key, data, output);
}
}

void Run_Des(void)
{
int select = 0;
string data, key;
cout << "1. encode;" << endl << "2. decode;" << endl << "Your choise: ";
cin >> select;
cout << endl << "Please input the data: ";
cin >> data;
cout << endl << "Please input the key: ";
cin >> key;

_b64 output;

if (select == 1) {
Des(key, data, output, true);
}else {
Des(key, data, output, false);
}
}

}

G. 用C语言来实现DES加密算法（很急）两天内

DES虽然不难但是挺繁复的，代码如下，关键点都有英文解释，仔细看。各个函数的功能都可以从函数名看出来。

#include "pch.h"
#include "misc.h"
#include "des.h"

NAMESPACE_BEGIN(CryptoPP)

/* Tables defined in the Data Encryption Standard documents
* Three of these tables, the initial permutation, the final
* permutation and the expansion operator, are regular enough that
* for speed, we hard-code them. They're here for reference only.
* Also, the S and P boxes are used by a separate program, gensp.c,
* to build the combined SP box, Spbox[]. They're also here just
* for reference.
*/
#ifdef notdef
/* initial permutation IP */
static byte 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
};

/* final permutation IP^-1 */
static byte fp[] = {
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
};
/* expansion operation matrix */
static byte ei[] = {
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
};
/* The (in)famous S-boxes */
static byte sbox[8][64] = {
/* 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
};

/* 32-bit permutation function P used on the output of the S-boxes */
static byte p32i[] = {
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
};
#endif

/* permuted choice table (key) */
static const byte pc1[] = {
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
};

/* number left rotations of pc1 */
static const byte totrot[] = {
1,2,4,6,8,10,12,14,15,17,19,21,23,25,27,28
};

/* permuted choice key (table) */
static const byte pc2[] = {
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
};

/* End of DES-defined tables */

/* bit 0 is left-most in byte */
static const int bytebit[] = {
0200,0100,040,020,010,04,02,01
};

/* Set key (initialize key schele array) */
DES::DES(const byte *key, CipherDir dir)
: k(32)
{
SecByteBlock buffer(56+56+8);
byte *const pc1m=buffer; /* place to modify pc1 into */
byte *const pcr=pc1m+56; /* place to rotate pc1 into */
byte *const ks=pcr+56;
register int i,j,l;
int m;

for (j=0; j<56; j++) { /* convert pc1 to bits of key */
l=pc1[j]-1; /* integer bit location */
m = l & 07; /* find bit */
pc1m[j]=(key[l>>3] & /* find which key byte l is in */
bytebit[m]) /* and which bit of that byte */
? 1 : 0; /* and store 1-bit result */
}
for (i=0; i<16; i++) { /* key chunk for each iteration */
memset(ks,0,8); /* Clear key schele */
for (j=0; j<56; j++) /* rotate pc1 the right amount */
pcr[j] = pc1m[(l=j+totrot[i])<(j<28? 28 : 56) ? l: l-28];
/* rotate left and right halves independently */
for (j=0; j<48; j++){ /* select bits indivially */
/* check bit that goes to ks[j] */
if (pcr[pc2[j]-1]){
/* mask it in if it's there */
l= j % 6;
ks[j/6] |= bytebit[l] >> 2;
}
}
/* Now convert to odd/even interleaved form for use in F */
k[2*i] = ((word32)ks[0] << 24)
| ((word32)ks[2] << 16)
| ((word32)ks[4] << 8)
| ((word32)ks[6]);
k[2*i+1] = ((word32)ks[1] << 24)
| ((word32)ks[3] << 16)
| ((word32)ks[5] << 8)
| ((word32)ks[7]);
}

if (dir==DECRYPTION) // reverse key schele order
for (i=0; i<16; i+=2)
{
std::swap(k[i], k[32-2-i]);
std::swap(k[i+1], k[32-1-i]);
}
}
/* End of C code common to both versions */

/* C code only in portable version */

// Richard Outerbridge's initial permutation algorithm
/*
inline void IPERM(word32 &left, word32 &right)
{
word32 work;

work = ((left >> 4) ^ right) & 0x0f0f0f0f;
right ^= work;
left ^= work << 4;
work = ((left >> 16) ^ right) & 0xffff;
right ^= work;
left ^= work << 16;
work = ((right >> 2) ^ left) & 0x33333333;
left ^= work;
right ^= (work << 2);
work = ((right >> 8) ^ left) & 0xff00ff;
left ^= work;
right ^= (work << 8);
right = rotl(right, 1);
work = (left ^ right) & 0xaaaaaaaa;
left ^= work;
right ^= work;
left = rotl(left, 1);
}
inline void FPERM(word32 &left, word32 &right)
{
word32 work;

right = rotr(right, 1);
work = (left ^ right) & 0xaaaaaaaa;
left ^= work;
right ^= work;
left = rotr(left, 1);
work = ((left >> 8) ^ right) & 0xff00ff;
right ^= work;
left ^= work << 8;
work = ((left >> 2) ^ right) & 0x33333333;
right ^= work;
left ^= work << 2;
work = ((right >> 16) ^ left) & 0xffff;
left ^= work;
right ^= work << 16;
work = ((right >> 4) ^ left) & 0x0f0f0f0f;
left ^= work;
right ^= work << 4;
}
*/

// Wei Dai's modification to Richard Outerbridge's initial permutation
// algorithm, this one is faster if you have access to rotate instructions
// (like in MSVC)
inline void IPERM(word32 &left, word32 &right)
{
word32 work;

right = rotl(right, 4U);
work = (left ^ right) & 0xf0f0f0f0;
left ^= work;
right = rotr(right^work, 20U);
work = (left ^ right) & 0xffff0000;
left ^= work;
right = rotr(right^work, 18U);
work = (left ^ right) & 0x33333333;
left ^= work;
right = rotr(right^work, 6U);
work = (left ^ right) & 0x00ff00ff;
left ^= work;
right = rotl(right^work, 9U);
work = (left ^ right) & 0xaaaaaaaa;
left = rotl(left^work, 1U);
right ^= work;
}

inline void FPERM(word32 &left, word32 &right)
{
word32 work;

right = rotr(right, 1U);
work = (left ^ right) & 0xaaaaaaaa;
right ^= work;
left = rotr(left^work, 9U);
work = (left ^ right) & 0x00ff00ff;
right ^= work;
left = rotl(left^work, 6U);
work = (left ^ right) & 0x33333333;
right ^= work;
left = rotl(left^work, 18U);
work = (left ^ right) & 0xffff0000;
right ^= work;
left = rotl(left^work, 20U);
work = (left ^ right) & 0xf0f0f0f0;
right ^= work;
left = rotr(left^work, 4U);
}

// Encrypt or decrypt a block of data in ECB mode
void DES::ProcessBlock(const byte *inBlock, byte * outBlock) const
{
word32 l,r,work;

#ifdef IS_LITTLE_ENDIAN
l = byteReverse(*(word32 *)inBlock);
r = byteReverse(*(word32 *)(inBlock+4));
#else
l = *(word32 *)inBlock;
r = *(word32 *)(inBlock+4);
#endif

IPERM(l,r);

const word32 *kptr=k;

for (unsigned i=0; i<8; i++)
{
work = rotr(r, 4U) ^ kptr[4*i+0];
l ^= Spbox[6][(work) & 0x3f]
^ Spbox[4][(work >> 8) & 0x3f]
^ Spbox[2][(work >> 16) & 0x3f]
^ Spbox[0][(work >> 24) & 0x3f];
work = r ^ kptr[4*i+1];
l ^= Spbox[7][(work) & 0x3f]
^ Spbox[5][(work >> 8) & 0x3f]
^ Spbox[3][(work >> 16) & 0x3f]
^ Spbox[1][(work >> 24) & 0x3f];

work = rotr(l, 4U) ^ kptr[4*i+2];
r ^= Spbox[6][(work) & 0x3f]
^ Spbox[4][(work >> 8) & 0x3f]
^ Spbox[2][(work >> 16) & 0x3f]
^ Spbox[0][(work >> 24) & 0x3f];
work = l ^ kptr[4*i+3];
r ^= Spbox[7][(work) & 0x3f]
^ Spbox[5][(work >> 8) & 0x3f]
^ Spbox[3][(work >> 16) & 0x3f]
^ Spbox[1][(work >> 24) & 0x3f];
}

FPERM(l,r);

#ifdef IS_LITTLE_ENDIAN
*(word32 *)outBlock = byteReverse(r);
*(word32 *)(outBlock+4) = byteReverse(l);
#else
*(word32 *)outBlock = r;
*(word32 *)(outBlock+4) = l;
#endif
}

void DES_EDE_Encryption::ProcessBlock(byte *inoutBlock) const
{
e.ProcessBlock(inoutBlock);
d.ProcessBlock(inoutBlock);
e.ProcessBlock(inoutBlock);
}

void DES_EDE_Encryption::ProcessBlock(const byte *inBlock, byte *outBlock) const
{
e.ProcessBlock(inBlock, outBlock);
d.ProcessBlock(outBlock);
e.ProcessBlock(outBlock);
}

void DES_EDE_Decryption::ProcessBlock(byte *inoutBlock) const
{
d.ProcessBlock(inoutBlock);
e.ProcessBlock(inoutBlock);
d.ProcessBlock(inoutBlock);
}

void DES_EDE_Decryption::ProcessBlock(const byte *inBlock, byte *outBlock) const
{
d.ProcessBlock(inBlock, outBlock);
e.ProcessBlock(outBlock);
d.ProcessBlock(outBlock);
}

void TripleDES_Encryption::ProcessBlock(byte *inoutBlock) const
{
e1.ProcessBlock(inoutBlock);
d.ProcessBlock(inoutBlock);
e2.ProcessBlock(inoutBlock);
}

void TripleDES_Encryption::ProcessBlock(const byte *inBlock, byte *outBlock) const
{
e1.ProcessBlock(inBlock, outBlock);
d.ProcessBlock(outBlock);
e2.ProcessBlock(outBlock);
}

void TripleDES_Decryption::ProcessBlock(byte *inoutBlock) const
{
d1.ProcessBlock(inoutBlock);
e.ProcessBlock(inoutBlock);
d2.ProcessBlock(inoutBlock);
}

void TripleDES_Decryption::ProcessBlock(const byte *inBlock, byte *outBlock) const
{
d1.ProcessBlock(inBlock, outBlock);
e.ProcessBlock(outBlock);
d2.ProcessBlock(outBlock);
}

H. 谁可以给我一个c语言写的DES代码,要求(输入任意一个字符串,可以得到相应的密文)

首先新建头文件des_encode.H
内容如下：
void EncodeMain(); //EncodeMain function
void DecodeMain(); //Sorry ,it has not used
void Decode(int *str,int *keychar); //decode :input 8 chars,8 keychars
void Encode(int *str,int *keychar); //encode: input 8 chars,8 keychars
void keyBuild(int *keychar); //create key array
void StrtoBin(int *midkey,int *keychar); //change into binary
void keyCreate(int *midkey2,int movebit,int i); //call by keyBuild
void EncodeData(int *lData,int *rData,int *srt); //encodedata function
void F(int *rData,int *key); //F function
void Expand(int *rData,int *rDataP); //Expand function
void ExchangeS(int *rDataP,int *rData); //S-diagram change
void ExchangeP(int *rData); //P change
void FillBin(int *rData,int n,int s); // data to binary;call by S-Diagram change function
void DecodeData(int *str,int *lData,int *rData); //DecodeData from binary
int IP1[]={58, 50, 42, 34, 26, 18, 10, 2, 60, 52, 44, 36, 28, 20, 12, 4, //initial change
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 IP2[]={40, 8, 48, 16, 56, 24, 64, 32, 39, 7, 47, 15, 55, 23, 63, 31, //opp initial change
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
};
int s[][4][16]={{ //S-diagram array
{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}
}
};
int Ex[48]={ 32,1,2,3,4,5, //Expand array
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]={16,7,20,21, //P-change
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
};
int PC1[56]={57,49,41,33,25,17,9, //PC-1 in keyBuild
1,58,50,42,34,26,18,
10,2,59,51,43,35,27,
19,11,3,60,52,44,36,
63,55,47,39,31,33,15,
7,62,54,46,38,30,22,
14,6,61,53,45,37,29,
21,13,5,28,20,12,4
};
int PC2[48]={14,17,11,24,1,5, //PC-2 in keyBuild
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
};

再创建des.cpp
内容如下：
#include<stdio.h>
#include<string.h>
#include"des_encode.h"
int key[16][48];
char str[8];
void main() //main function
{
EncodeMain();

}

void EncodeMain() //EncodeMain function
{
int i;

char keychar[8];

int key2[8];
int strkey[8];

printf("请输入8个要加密的字符：\n");
for(i=0;i<8;i++)
scanf("%c",&str[i]);
getchar();
for(i=0;i<8;i++)
strkey[i]=str[i];
printf("\n输入明文的十六进制为:\n");
for(i=0;i<8;i++)
printf("%10x",strkey[i]);
printf("\n请输入密钥(8个字符):\n");
for(i=0;i<8;i++)
scanf("%c",&keychar[i]);
for(i=0;i<8;i++)
key2[i]=keychar[i];
getchar();
// printf("%c",keychar[i]);
Encode(strkey,key2);
printf("\n加密后十六进制密文是:\n");
for(i=0;i<8;i++)
printf("%10x",strkey[i]);
printf("\n\n清输入解密密码\n");
for(i=0;i<8;i++)
scanf("%c",&keychar[i]);
for(i=0;i<8;i++)
key2[i]=keychar[i];
Decode(strkey,key2);
for(i=0;i<8;i++)
printf("%10x",strkey[i]);
for(i=0;i<8;i++)
str[i]=strkey[i];
printf("\n明文为：\t");
for(i=0;i<8;i++)
printf("%c",str[i]);
printf("\n\n");

}

void keyBuild(int *keychar){ //create key array
int i,j;
int movebit[]={1,1,2,2,2,2,2,2,
1,2,2,2,2,2,2,1};
int midkey2[56];
int midkey[64];
StrtoBin(midkey,keychar);
for(i=0;i<56;i++)
midkey2[i]=midkey[PC1[i]-1];
for(i=0;i<16;i++)
keyCreate(midkey2,movebit[i],i);
}
void StrtoBin(int *midkey,int *keychar){ //change into binary
int trans[8],i,j,k,n;
n=0;
for(i=0;i<8;i++){
j=0;
while(keychar[i]!=0){
trans[j]=keychar[i]%2;
keychar[i]=keychar[i]/2;
j++;
}
for(k=j;k<8;k++)trans[k]=0;
for(k=0;k<8;k++)
midkey[n++]=trans[7-k];
}
}
void keyCreate(int *midkey2,int movebit,int n){
int i,temp[4];
temp[0]=midkey2[0];
temp[1]=midkey2[1];
temp[2]=midkey2[28];
temp[3]=midkey2[29];
if(movebit==2){
for(i=0;i<26;i++){
midkey2[i]=midkey2[i+2];
midkey2[i+28]=midkey2[i+30];
}
midkey2[26]=temp[0];midkey2[27]=temp[1];
midkey2[54]=temp[2];midkey2[55]=temp[3]; }
else
{ for(i=0;i<27;i++){
midkey2[i]=midkey2[i+1];
midkey2[i+28]=midkey2[i+29];
}
midkey2[27]=temp[0];midkey2[55]=temp[2];
}
for(i=0;i<48;i++)
key[n][i]=midkey2[PC2[i]-1];
}
void EncodeData(int *lData,int *rData,int *str){ //encodedata function
int i,j,temp[8],lint,rint;//int h;
int data[64];
lint=0,rint=0;
for(i=0;i<4;i++){
j=0;
while(str[i]!=0){
temp[j]=str[i]%2;
str[i]=str[i]/2;
j++;
}
while(j<8)temp[j++]=0;
for(j=0;j<8;j++)
lData[lint++]=temp[7-j];
j=0;
while(str[i+4]!=0){
temp[j]=str[i+4]%2;
str[i+4]=str[i+4]/2;
j++;
}
while(j<8)temp[j++]=0;
for(j=0;j<8;j++)rData[rint++]=temp[7-j];
}
for(i=0;i<32;i++){
data[i]=lData[i];
data[i+32]=rData[i];
}

for(i=0;i<32;i++){
lData[i]=data[IP1[i]-1];//printf("P1:%5d:%5d,%5d\n",IP1[i],lData[i],data[IP1[i]-1]);
rData[i]=data[IP1[i+32]-1];
}
}
void F(int *rData,int *key){ //F function
int i,rDataP[48];
Expand(rData,rDataP);

for(i=0;i<48;i++){
rDataP[i]=rDataP[i]^key[i];// printf("%10d",rDataP[i]);if((i+1)%6==0)printf("\n");
}

ExchangeS(rDataP,rData);

ExchangeP(rData);

}
void Expand(int *rData,int *rDataP){ //Expand function
int i;
for(i=0;i<48;i++)
rDataP[i]=rData[Ex[i]-1];
}
void ExchangeS(int *rDataP,int *rData){ //S-diagram change
int i,n,linex,liney;
linex=liney=0;
for(i=0;i<48;i+=6){
n=i/6; //printf("%10d\n",(rDataP[i]<<1));
linex=(rDataP[i]<<1)+rDataP[i+5];
liney=(rDataP[i+1]<<3)+(rDataP[i+2]<<2)+(rDataP[i+3]<<1)+rDataP[i+4];

FillBin(rData,n,s[n][linex][liney]);
}
}
void ExchangeP(int *rData){ //P change
int i,temp[32];
for(i=0;i<32;i++)
temp[i]=rData[i];

for(i=0;i<32;i++)
rData[i]=temp[P[i]-1];
}
void FillBin(int *rData,int n,int s){ // data to binary;call by S-Diagram change function
int temp[4],i;
for(i=0;i<4;i++){
temp[i]=s%2;
s=s/2;
}
for(i=0;i<4;i++)
rData[n*4+i]=temp[3-i];
}
void DecodeData(int *str,int *lData,int *rData){ //DecodeData from binary
int i;int a,b;int data[64];
a=0,b=0;
for(i=0;i<32;i++){
data[i]=lData[i];
data[i+32]=rData[i];
}
for(i=0;i<32;i++){
lData[i]=data[IP2[i]-1];
rData[i]=data[IP2[i+32]-1];
}
for(i=0;i<32;i++){
a=(lData[i]&0x1)+(a<<1);
b=(rData[i]&0x1)+(b<<1);
if((i+1)%8==0){
str[i/8]=a;a=0;//printf("%d",i/8);
str[i/8+4]=b;b=0;//printf("%d",i/8+4);
}
}

}

void Encode(int *str,int *keychar){ //encode: input 8 chars,8 keychars
int lData[32],rData[32],temp[32],rDataP[48];
int i,j;
keyBuild(keychar);

EncodeData(lData,rData,str);
for(i=0;i<16;i++){
for(j=0;j<32;j++)
temp[j]=rData[j];
F(rData,key[i]);
for(j=0;j<32;j++){
rData[j]=rData[j]^lData[j];
}

for(j=0;j<32;j++)
lData[j]=temp[j];
}

DecodeData(str,rData,lData);

}
void Decode(int *str,int *keychar){ //decode :input 8 chars,8 keychars
int lData[32],rData[32],temp[32],rDataP[48];
int i,j;
keyBuild(keychar);
EncodeData(lData,rData,str); //这个位置
for(i=0;i<16;i++){
for(j=0;j<32;j++)
temp[j]=rData[j];
F(rData,key[15-i]);
for(j=0;j<32;j++){
rData[j]=rData[j]^lData[j];
}

for(j=0;j<32;j++){
lData[j]=temp[j];
}
}
DecodeData(str,rData,lData);
}

OK了
如果还有问题
给我发站内信

I. 求一个用c语言写的DES加密算法~~

using system;
using system.security.cryptography;
using system.io;
using system.text;

public class encryptstringdes {

public static void main(string);
return;
}

// 使用utf8函数加密输入参数
utf8encoding utf8encoding = new utf8encoding();
byte.tochararray());

// 方式一：调用默认的des实现方法des_csp.
des des = des.create();
// 方式二：直接使用des_csp()实现des的实体
//des_csp des = new des_csp();

// 初始化des加密的密钥和一个随机的、8比特的初始化向量(iv)
byte iv = {0x12, 0x34, 0x56, 0x78, 0x90, 0xab, 0xcd, 0xef};
des.key = key;
des.iv = iv;

// 建立加密流
symmetricstreamencryptor sse = des.createencryptor();

// 使用cryptomemorystream方法获取加密过程的输出
cryptomemorystream cms = new cryptomemorystream();

// 将symmetricstreamencryptor流中的加密数据输出到cryptomemorystream中
sse.setsink(cms);

// 加密完毕，将结果输出到控制台
sse.write(inputbytearray);
sse.closestream();

// 获取加密数据
byte);
}
console.writeline();

//上面演示了如何进行加密，下面演示如何进行解密
symmetricstreamdecryptor ssd = des.createdecryptor();
cms = new cryptomemorystream();
ssd.setsink(cms);
ssd.write(encrypteddata);
ssd.closestream();

byte decryptedchararray = utf8encoding.getchars(decrypteddata);
console.writeline("解密后数据：");
console.write(decryptedchararray);
console.writeline();
}
}

编译：

d:\csharp>csc des_demo.cs
microsoft (r) c# compiler version 7.00.8905
right (c) microsoft corp 2000. all rights reserved.

运行实例：
d:\csharp>des_demo.exe 使用c#编写des加密程序的framework

加密结果：
3d 22 64 c6 57 d1 c4 c3 cf 77 ce 2f d0 e1 78 2a 4d ed 7a a8 83 f9 0e 14 e1 ba 38
7b 06 41 8d b5 e9 3f 00 0d c3 28 d1 f9 6d 17 4b 6e a7 41 68 40

J. c语言 c# des 有人做过两种语言des通信加密吗教教我

/// <summary>
/// DES加密（使用自定义密钥）（对称密码）
/// </summary>
/// <param name="strSource">待加密字串</param>
/// <param name="key">32位Key值</param>
/// <returns>加密后的字符串</returns>
public static string DESEncrypt(string strSource, byte[] key)
{
SymmetricAlgorithm sa = Rijndael.Create();
sa.Key = key;
sa.Mode = CipherMode.ECB;
sa.Padding = PaddingMode.Zeros;
MemoryStream ms = new MemoryStream();
CryptoStream cs = new CryptoStream(ms, sa.CreateEncryptor(), CryptoStreamMode.Write);
byte[] byt = Encoding.Unicode.GetBytes(strSource);
cs.Write(byt, 0, byt.Length);
cs.FlushFinalBlock();
cs.Close();
return Convert.ToBase64String(ms.ToArray());
}

实现的方法有很多，这是其中一个第一个是加密的字符串
参数的第二个是你的密匙，32位的字符，要解密的话，也必须需要你的密匙