Diffie-Hellman密钥交换综合实验报告

1、（网络安全方案设计基础）实验报告 #代码可运行时间： 2021年 5月 12日 1-2 节 地点：软件实验室姓 名班 级学 号指导教师实验成绩小李物联网18-1180*实验名称Diffie-Hellman密钥交换算法实验目的1、了解和掌握Diffie-Hellman算法原理及过程；2、通过密钥交换算法实现对称加解密密钥的保密传输；3、能够编写代码实现Diffie-Hellman算法，并实现数据保密传输。实验内容1、编写Diffie-Hellman程序，协商出用于收、发双方的加、解密密钥K；2、模拟发送端A，用协商出的密钥K，通过对称加密算法（具体算法不限）将文本文件加密；模拟接收端B，用协商出

2、的密钥K，对接收到的密文解密。实验过程#include #include /*函数声明*/void InitSbox(unsigned char sbox); void KeyExpansion(unsigned char key, char *k, int len);void UpsetSbox(unsigned char sbox, unsigned char key);void DataProcess(unsigned char sbox, FILE *fp1, FILE *fp2);void DataEncrypt(char *k, unsigned char *key, unsign

3、ed char *sbox, FILE *fp1, FILE *fp2);void DataDecrypt(char *k1, unsigned char *key, unsigned char *sbox, FILE *fp1, FILE *fp2);int write_file(char name,char data,int size);int read_file(char name,char data,int size);int usera();int userb();int Xa = 3, Xb = 5, Ya, Yb;/*初始化S盒*/void InitSbox(unsigned c

4、har sbox)int i;for( i = 0; i 256; i+) sboxi = i; /*密钥填充256数组*/void KeyExpansion(unsigned char key, char *k, int len)int i;if(len = 256)for( i = 0; i 256)for( i = 0; i 256; i+) keyi = ki; /*打乱S盒*/ void UpsetSbox(unsigned char sbox, unsigned char key)int j = 0,i;unsigned char temp;int n;for( i = 0; i

5、256; i+)n = j + (int)sboxi + (int)keyi;j = n % 256;temp = sboxi;sboxi = sboxj;sboxj = temp; /*加解密数据*/ void DataProcess(unsigned char sbox, FILE *fp1, FILE *fp2)/0加密，1解密int i=0, j=0,size=0;int temp2,temp1,t;char k,cipherchar,data_Stream100=0 x00;unsigned char temp;char ch = fgetc(fp1);while(ch != EOF

6、)printf(%c,ch);i = (i + 1) % 256; temp2 = j + (int)sboxi;j = temp2 % 256;temp = sboxi;sboxi = sboxj;sboxj = temp; temp1 = (int)sboxi + (int)sboxj; t = temp1 % 256;data_Streamsize+= k = sboxt; cipherchar = ch k;fputc(cipherchar, fp2);ch = fgetc(fp1);write_file(Stream.txt,data_Stream,size); /*加密总函数*/v

7、oid DataEncrypt(unsigned char *k, unsigned char *key, unsigned char *sbox, FILE *fp1, FILE *fp2) int len = strlen(k); KeyExpansion(key, k, len); InitSbox(sbox); UpsetSbox(sbox, key); printf(n明文为：); DataProcess(sbox, fp1, fp2); fclose(fp1); fclose(fp2); printf(n加密成功，加密内容存于“Ciphertext.txt”中nn); /*解密总函

8、数*/ void DataDecrypt(unsigned char *k1, unsigned char *key, unsigned char *sbox, FILE *fp1, FILE *fp2) int len = strlen(k1); KeyExpansion(key, k1, len); InitSbox(sbox); UpsetSbox(sbox, key);printf(n密文为：); DataProcess(sbox, fp1, fp2); fclose(fp1); fclose(fp2); printf(n解密成功，解密内容存于“Plaintext.txt”中!nn);

9、/*文件的写操作*/int write_file(char name,char data,int size) FILE *file=fopen(name,ab+);if(file=NULL) return 0; fwrite(data,sizeof(char),size,file);/写入一个数组 rewind(file);/移动指针到开头 fclose(file); return 1;/*文件的读操作*/int read_file(unsigned char name,char data,int size) FILE *file=fopen(name,rb+);if(file=NULL) r

10、eturn 0; rewind(file);/移动指针到开头 fread(data,sizeof(char),size,file);/读出一个数组 fclose(file); return 1;int main(int argc, const char * argv) int q = 11, alpha = 2; unsigned char k1res ; unsigned char k2res ;/*RC4变量*/unsigned char key125=0 x00,key225=0 x00;unsigned char key256 = 0 x00;unsigned char sbox256

11、 = 0 x00;FILE *fp1, *fp2; int flag = 1,i;/*A端操作*/printf(*A端操作*n);printf( q=11, a=2, Xa=3 n); /计算 Ya Ya = pow(alpha,Xa); Ya = Ya % q; printf(计算得出:Ya=(a)Xa mod q = %dn,Ya);printf(把Ya发送给B端.n); /*B端操作*/ printf(*B端操作*n);printf( q=11, a=2, Xb=5 n);/计算 Yb Yb = pow(alpha,Xb); Yb = Yb % q; printf(计算得出:Yb=(a)

12、Xb mod q = %dn,Yb);printf(把Yb发送给A端.nn); /*AB端收到数据后解密*/printf(*AB端计算秘钥结果*n); /把Yb给程序A并解出秘钥 k1res = usera(alpha,q);/把Ya给程序B并解出秘钥 k2res = userb(alpha,q);key10=k1res;key20=k2res; printf(nA程序收到Yb后计算，得到秘钥Ka:%d,k1res); printf(nB程序收到Ya后计算，得到秘钥Kb:%dn,k1res);/*RC4加密*/*加密*/ printf(n*A端进行RC4加密*n); fp1 = fopen(S

13、ource.txt,r); if(fp1 = NULL) printf(打开源文件失败!n); getchar(); exit(0); fp2 = fopen(Ciphertext.txt,w); if(fp2 = NULL) printf(打开加密后文件失败!n); getchar(); exit(0); printf(利用Ka加密进行加密); DataEncrypt(key1, key, sbox, fp1, fp2); /*解密*/ printf(*B端进行RC4解密*n); fp1 = fopen(Ciphertext.txt,r); if(fp1 = NULL) printf(打开加

14、密后文件失败!n); getchar(); exit(0); fp2 = fopen(Plaintext.txt,w); if(fp2 = NULL) printf(打开解密后文件失败!n); getchar(); exit(0); /read_file(Key.txt,key2,11); printf(利用Kb加密进行解密); DataDecrypt(key2, key, sbox, fp1, fp2);/*/return 0;int usera(alpha,q) int k1 = pow(Yb, Xa); k1 = k1 % q; return k1;int userb(alpha,q) int k2 = pow(Ya, Xb); k2 = k2 % q; return k2;实验结果主代码的运行结果（图1）：图1存储明文的文件（图2）：图2存储密文的文