des_cmac.cpp

#include<stdio.h>
#include<string.h>
#include<string>
#include<stdlib.h>
#include<iostream>
using namespace std;
void keyBuild(int *keychar);                                     //create key array
void keyCreate(int *midkey2,int movebit,int i);         //call by keyBuild
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 InitialPermutation(int *plaintext_64bit);
void Hex2Bit(char *text_byte,int *text_bit,int n);    //change into bit,n为bit的位数
void Bit2Hex(char *text_byte,int* text_bit,int n);    //change into hex,n为bit的位数
void RoundEncode(int n);
void cmac();
void Encode_cmac();
void k1_k2_create();
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]={16,7,20,21,29,12,28,17,                                                               //P-change
           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,
             63,55,47,39,31,23,15,
             7,62,54,46,38,30,22,
             14,6,61,53,45,37,29,
             21,13,5,28,20,12,4
 };
int PC2[48]={14,17,11,24,1,5,3,28,                                                     //PC-2 in keyBuild
             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
 };

int LSi[16]={1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1};

int subkey_bit[16][48];
char subkey_byte[16][16];
char plaintext_16byte[16];
int plaintext_64bit[64];
char ciphertext_16byte[16];
int ciphertext_64bit[64];
char key_16byte[16];
int key_64bit[64];
int mode;  //来区分是加密还是解密
string plaintext_cmac;
int k1[64];
char k1_byte[16];
int k1_temp[65];
int k2[64];
char k2_byte[16];
int k2_temp[66];
int main()                 //main function
{
    cmac();
    system("pause");
    return 0;
}
void cmac()
{
    cout<<"请输入密钥(16个字符):"<<endl;
    for(int i=0;i<16;i++)
        cin>>key_16byte[i];
    Hex2Bit(key_16byte,key_64bit,64);

    k1_k2_create();

    cout<<"请输入明文(可以大于16个字符)："<<endl;
    cin>>plaintext_cmac;
    int length=plaintext_cmac.size();
    cout<<"输入字符的长度为："<<length<<endl;
    for(int i=0;i<64;i++)
        //ciphertext_64bit初始化都为0！以便第一次异或ciphertext_64bit的时候没有取反！！
        ciphertext_64bit[i]=0;
    if(length%16==0)//如果输入的字符串长度正好是整数倍的分组长度，则如下处理
    {
        int i;
        for(i=0;i<length/16-1;i++)    //注意这里要-1
        {
            for(int j=0;j<16;j++)
                plaintext_16byte[j]=plaintext_cmac[j+i*16];
            Hex2Bit(plaintext_16byte,plaintext_64bit,64);
            for(int j=0;j<64;j++)
                plaintext_64bit[j]=plaintext_64bit[j]^ciphertext_64bit[j];
            Encode_cmac();
            cout<<"第"<<i+1<<"组加密后密文为："<<ciphertext_16byte<<endl;
        }
        for(int j=0;j<16;j++)
            plaintext_16byte[j]=plaintext_cmac[j+i*16];
        Hex2Bit(plaintext_16byte,plaintext_64bit,64);
        for(int j=0;j<64;j++)
            plaintext_64bit[j]=plaintext_64bit[j]^ciphertext_64bit[j];


        for(int j=0;j<64;j++)
            plaintext_64bit[j]=plaintext_64bit[j]^k1[j];//相当于与K1异或了！！！

        Encode_cmac();
        cout<<"第"<<i+1<<"组加密后密文为："<<ciphertext_16byte<<endl;
    }
    else if(length%16!=0)//如果输入的字符串长度不是整数倍的分组长度，则如下处理
    {
        int i;
        for(i=0;i<length/16;i++)   //注意这里不-1，与第一种情况不同。
        {
            for(int j=0;j<16;j++)
                plaintext_16byte[j]=plaintext_cmac[j+i*16];
            Hex2Bit(plaintext_16byte,plaintext_64bit,64);
            for(int j=0;j<64;j++)
                plaintext_64bit[j]=plaintext_64bit[j]^ciphertext_64bit[j];
            Encode_cmac();
            cout<<"第"<<i+1<<"组加密后密文为："<<ciphertext_16byte<<endl;
        }

        //下面几行与第一种情况主要不同的地方！！即处理100...000的情况
        for(int j=0;j<length%16;j++)
            plaintext_16byte[j]=plaintext_cmac[j+i*16];
        plaintext_16byte[length%16]='8';//即8=1000
        for(int j=length%16+1;j<16;j++)
            plaintext_16byte[j]='0';

        Hex2Bit(plaintext_16byte,plaintext_64bit,64);
        for(int j=0;j<64;j++)
            plaintext_64bit[j]=plaintext_64bit[j]^ciphertext_64bit[j];

        for(int j=0;j<64;j++)
            plaintext_64bit[j]=plaintext_64bit[j]^k2[j];;//相当于与K2异或了！！！

        Encode_cmac();
        cout<<"第"<<i+1<<"组加密后密文为："<<ciphertext_16byte<<endl;
    }
}
void Encode_cmac()
{
    InitialPermutation(plaintext_64bit);

    Hex2Bit(key_16byte,key_64bit,64);
    keyBuild(key_64bit);

    for(int i=0;i<16;i++)
    {
        RoundEncode(i);
        Bit2Hex(ciphertext_16byte,ciphertext_64bit,64);
    }
    int temp[64];   //逆初始置换
    for(int i=0;i<64;i++)
        temp[i]=ciphertext_64bit[i];
    for(int i=0;i<32;i++)
        ciphertext_64bit[i]=temp[i+32];
    for(int i=0;i<32;i++)
        ciphertext_64bit[i+32]=temp[i];

    for(int i=0;i<64;i++)
        temp[i]=ciphertext_64bit[i];
    for(int i=0;i<64;i++)
        ciphertext_64bit[i]=temp[ IP2[i]-1  ];
    Bit2Hex(ciphertext_16byte,ciphertext_64bit,64);
}
void k1_k2_create()   //用于产生k1和k2
{
    for(int i=0;i<64;i++)
        plaintext_64bit[i]=0;
    Encode_cmac();//对E(K,0^n)加密
    cout<<"L=E(K,0^n)="<<ciphertext_16byte<<endl;
    Hex2Bit(ciphertext_16byte,ciphertext_64bit,64);
    cout<<"L=E(K,0^n)二进制为：";
    for(int i=0;i<64;i++)
        cout<<ciphertext_64bit[i];
    cout<<endl;

    for(int i=0;i<64;i++)//给k1，k2赋初值，为L的值
    {
        k1[i]=ciphertext_64bit[i];
        k2[i]=ciphertext_64bit[i];
    }

    for(int i=0;i<64;i++)
        k1_temp[i]=k1[i];
    k1_temp[64]=0;//k1_temp为k1乘以x后的值。
    //if(k1_temp[0]==0)
    //由于要在有限域中取x^64+x^4+x^3+1 取余，当最高位即x^64为0的时候，k1不变，所以不用处理
    if(k1_temp[0]==1)
    {//取x^64+x^4+x^3+1 取余
        k1_temp[0]=k1_temp[0]^1;
        k1_temp[60]=k1_temp[60]^1;
        k1_temp[61]=k1_temp[61]^1;
        k1_temp[63]=k1_temp[63]^1;
        k1_temp[64]=k1_temp[64]^1;
    }
    for(int i=0;i<64;i++)
        k1[i]=k1_temp[i+1];//此时k1=L*x
    Bit2Hex(k1_byte,k1,64);
    cout<<"K1="<<k1_byte<<endl;

    for(int i=0;i<64;i++)
        k2_temp[i]=k2[i];
    k2_temp[64]=0;
    k2_temp[65]=0;//k2_temp为k2乘以x^2后的值。
    if(k2_temp[0]==1)
    {
        k2_temp[0]=k2_temp[0]^1;
        k2_temp[60]=k2_temp[60]^1;
        k2_temp[61]=k2_temp[61]^1;
        k2_temp[63]=k2_temp[63]^1;
        k2_temp[64]=k2_temp[64]^1;
    }
    if(k2_temp[1]==1)
    {
        k2_temp[1]=k2_temp[1]^1;
        k2_temp[61]=k2_temp[61]^1;
        k2_temp[62]=k2_temp[62]^1;
        k2_temp[64]=k2_temp[64]^1;
        k2_temp[65]=k2_temp[65]^1;
    }
    for(int i=0;i<64;i++)
        k2[i]=k2_temp[i+2];//此时k2=L*x^2
    Bit2Hex(k2_byte,k2,64);
    cout<<"K2="<<k2_byte<<endl;

}
void InitialPermutation(int *plaintext_64bit)
{
    int temptext[64];
    for(int i=0;i<64;i++)
        temptext[i]=plaintext_64bit[i];
    for(int i=0;i<64;i++)
        temptext[i]=plaintext_64bit[IP1[i]-1];
    for(int i=0;i<64;i++)
        ciphertext_64bit[i]=temptext[i];
    Bit2Hex(ciphertext_16byte,temptext,64);
}
void Hex2Bit(char *text_byte,int *text_bit,int n)    //change into bit,n为bit的位数
{
    int length=n/4;
    int temptext[length];
    for(int i=0;i<length;i++)
    {
        if(text_byte[i]>='a'&&text_byte[i]<='f')
            temptext[i]=text_byte[i]-'a'+10;
        else if(text_byte[i]>='0'&&text_byte[i]<='9')
            temptext[i]=text_byte[i]-'0';
    }
    for(int i=0;i<length;i++)
    {
        for(int j=3;j>=0;j--)
        {
            text_bit[i*4+j]=temptext[i]%2;
            temptext[i]/=2;
        }
    }
}
void Bit2Hex(char *text_byte,int* text_bit,int n)    //change into hex,n为bit的位数
{
    int length=n/4;
    int temptext[length];
    for(int i=0;i<length;i++)
    {
        temptext[i]=text_bit[i*4+0]*8;
        temptext[i]+=text_bit[i*4+1]*4;
        temptext[i]+=text_bit[i*4+2]*2;
        temptext[i]+=text_bit[i*4+3]*1;
    }
    for(int i=0;i<length;i++)
    {
        if(temptext[i]>=0&&temptext[i]<=9)
            text_byte[i]=temptext[i]+'0';
        else if(temptext[i]>=10&&temptext[i]<=15)
            text_byte[i]=(temptext[i]-10)+'a';
    }
}

void keyBuild(int *keychar)   //create key array
{
    int i,j,k;
    int movebit[]={1,1,2,2,2,2,2,2,
                   1,2,2,2,2,2,2,1};
    int midkey2[56];
    int midkey[64];
	int key[56];
	for(k=0;k<56;k++)
	{
      midkey2[k]=keychar[PC1[k]-1];
	}
    for(i=0;i<16;i++)                   //密钥按照移位表循环左移,i代表轮数
	{

      keyCreate(midkey2,movebit[i],i);
	}
}
// midkey2是pc-1置换后的56bit密钥，movebit为左移的位数，n为第几轮
void keyCreate(int *midkey2,int movebit,int n)  //create key
{
    int i,temp[4];
    temp[0]=midkey2[0];
    temp[1]=midkey2[1];
    temp[2]=midkey2[28];
    temp[3]=midkey2[29];
   if(movebit==2)      //左移两位的算法
   {
       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                     //左移一位的算法
     { 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];
     }
	 //pc-2置换后变成48位
    for(i=0;i<48;i++)
	{
      subkey_bit[n][i]=midkey2[PC2[i]-1];
	}
    Bit2Hex(subkey_byte[n],subkey_bit[n],48);
}


void RoundEncode(int n)  //第n轮加密
{
    int lData[32],rData[32];
    int rDataE[48];
    for(int i=0;i<32;i++)
        lData[i]=ciphertext_64bit[i];
    for(int i=0;i<32;i++)
        rData[i]=ciphertext_64bit[i+32];
    Expand(rData,rDataE);
    for(int i=0;i<48;i++)     //取异或
        rDataE[i]=rDataE[i]^subkey_bit[n][i];
    ExchangeS(rDataE,rData);  //S盒变换
    ExchangeP(rData);         //P置换
    for(int i=0;i<32;i++)      //取异或
        rData[i]=rData[i]^lData[i];
    for(int i=0;i<32;i++)
        ciphertext_64bit[i]=ciphertext_64bit[i+32];
    for(int i=0;i<32;i++)
        ciphertext_64bit[i+32]=rData[i];
}
void F(int *rData,int *key)     //F function
{
    int i,rDataP[48];
    Expand(rData,rDataP);    //将明文右半部分进行E扩展，扩展成48位的A
    for(i=0;i<48;i++)
	{
      rDataP[i]=rDataP[i]^key[i];    //将进行完E扩展的A与key1异或
    }
    ExchangeS(rDataP,rData);  //S盒变换
    ExchangeP(rData);
}
void Expand(int *rData,int *rDataP) //E扩展  将明文右半部分进行E扩展，扩展成48位
{
    int i;
    char temp[12];
    for(i=0;i<48;i++)
	{
      rDataP[i]=rData[Ex[i]-1];
	}
	Bit2Hex(temp,rDataP,48);
}
void ExchangeS(int *rDataP,int *rData){          //S盒变换
    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]);

    }
    char temp[8];
    Bit2Hex(temp,rData,32);
}
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 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];
	char temp2[8];
	Bit2Hex(temp2,rData,32);
}