des.cpp

这个程序是实现 DES算法的

#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); 
   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 schedule 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("\n该程序的密钥是: %s",key); 
   m_dwlKey=ProcessByte((unsigned char*)key,TRUE); 
   m_dwlKey=PermuteTable(m_dwlKey,dwlKey_PC_1,56); 
   Generate_K(); 
 } 
//.....................................................................
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,DWORDLONG* 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("\n该程序的明文是: %s\n",block); 
   m_dwlData=ProcessByte(block,0); 
   m_dwlData=PermuteTable(m_dwlData,dwlData_IP,64); 
   EncryptKernel(); 
   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("\n加密后的信息: %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); 
   EK=R[i-1]^m_dwl_K[i]; 
   PSB=Generate_B(EK,B); 
   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); 
   EK=L[i]^m_dwl_K[i]; 
   PSB=Generate_B(EK,B); 
   L[i-1]=R[i]^PSB; 
   } 

  L[0]<<=32; 
  dataPara=L[0]|R[0]; 
  dataPara=PermuteTable(dataPara,dwlData_FP,64); 

  for(i=0;i<8;i++){ 
  DescryptedData[7-i]=(unsigned char)(dataPara&0xff); 
  dataPara>>=8; 
  } 
  DescryptedData[8]='\0'; 
  printf("\n解密后的信息为: %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()
{
	printf("*************************************************\n");
	printf("*                                               *\n");
	printf("*           信息安全作业------蔡标              *\n");
    printf("*                                               *\n");
	printf("*************************************************\n");
    CDES des; 
    des.EncryptKey("123"); 
	printf("\n*************************************************");
    unsigned char *result=des.EncryptData((unsigned char*)"CAI BIAO"); 
	printf("\n*************************************************");
    des.DescryptData(result); 
	printf("\n*************************************************");
    printf("\n@BYEBYE@\n");
	printf("\n*************************************************\n");

}