DES算法,头文件

博客展示了DES算法的实现,包含一个DES类,其中有加密、解密等方法,还涉及对不同大小数据的处理。头文件是改写过的,代码中定义了多种函数和静态变量用于算法的具体操作。

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DES算法,头文件


自己改写过,请指教
#ifndef __DES_H
#define __DES_H

class DES
{
public:
// Encrypt/decrypt the data in "data", according to the "key".
// Caller is responsible for confirming the buffer size of "data"
// points to is 8*"blocks" bytes.
// The data encrypted/decrypted is stored in data.
// The return code is 1:success, other:failed.
int encrypt ( char key[8], char* data, int blocks = 1 );
int decrypt ( char key[8], char* data, int blocks = 1 );

// Encrypt/decrypt any size data,according to a special method.
// Before calling yencrypt, copy data to a new buffer with size
// calculated by extend.
int yencrypt ( char key[8], char* data, int size );
int ydecrypt ( char key[8], char* in, int blocks, int* size = 0 );

int extend ( int size ) { return (size/8+1)*8; };

private:
void des(unsigned char* in, unsigned char* out, int blocks);
void des_block(unsigned char* in, unsigned char* out);

private:
unsigned long KnL[32];
enum Mode { ENCRYPT, DECRYPT };
void deskey(unsigned char key[8], Mode md);
void usekey(unsigned long *);
void cookey(unsigned long *);

private:
void scrunch(unsigned char *, unsigned long *);
void unscrun(unsigned long *, unsigned char *);
void desfunc(unsigned long *, unsigned long *);

private:
static unsigned char Df_Key[24];
static unsigned short bytebit[8];
static unsigned long bigbyte[24];
static unsigned char pc1[56];
static unsigned char totrot[16];
static unsigned char pc2[48];
static unsigned long SP1[64];
static unsigned long SP2[64];
static unsigned long SP3[64];
static unsigned long SP4[64];
static unsigned long SP5[64];
static unsigned long SP6[64];
static unsigned long SP7[64];
static unsigned long SP8[64];

};

#endif


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DES算法的C语言代码及实现 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); }
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