finally get dh.c XD

dh.c

+/*socket programming part comes from comp30023 lab5 sample code.
+  credit to the person who write that sample code*/
+
+
+/* A simple client program for server.c
+
+   To compile: gcc client.c -o client
+
+   To run: start the server, then the client */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <string.h>
+#include <strings.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <unistd.h>
+#include <ctype.h>
+
+// Function to compute a^m mod n, comes from www.techiedelight.com
+int compute(int a, int m, int n)
+{
+	int r;
+	int y = 1;
+
+	while (m > 0)
+	{
+		r = m % 2;
+
+		// fast exponention
+		if (r == 1)
+			y = (y*a) % n;
+		a = a*a % n;
+
+		m = m / 2;
+	}
+
+	return y;
+}
+
+int main(int argc, char ** argv)
+{
+    int sockfd, portno, n;
+    struct sockaddr_in serv_addr;
+    struct hostent * server;
+
+    char buffer[256];
+
+    portno = 7800;
+
+
+    /* Translate host name into peer's IP address ;
+     * This is name translation service by the operating system
+     */
+    server = gethostbyname("172.26.37.44");
+
+    if (server == NULL)
+    {
+        fprintf(stderr, "ERROR, no such host\n");
+        exit(0);
+    }
+
+    /* Building data structures for socket */
+
+    bzero((char *)&serv_addr, sizeof(serv_addr));
+
+    serv_addr.sin_family = AF_INET;
+
+    bcopy(server->h_addr_list[0], (char *)&serv_addr.sin_addr.s_addr, server->h_length);
+
+    serv_addr.sin_port = htons(portno);
+
+    /* Create TCP socket -- active open
+    * Preliminary steps: Setup: creation of active open socket
+    */
+
+    sockfd = socket(AF_INET, SOCK_STREAM, 0);
+
+    if (sockfd < 0)
+    {
+        perror("ERROR opening socket");
+        exit(0);
+    }
+
+    if (connect(sockfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0)
+    {
+        perror("ERROR connecting");
+        exit(0);
+    }
+
+    /* Do processing
+    */
+
+    //send user name
+
+    bzero(buffer, 256);
+
+    sprintf(buffer, "xiaoxuanl4\n");
+    n = write(sockfd, buffer, strlen(buffer));
+    printf("%s\n", buffer);
+
+    //send g^b(mod p)
+
+    int g=15;
+    int p=97;
+
+    bzero(buffer, 256);
+
+    char hash[256];
+    FILE* file = popen("openssl sha256 dh.c", "r");
+    if(!file){
+        printf("something wrong with your command or file\n");
+        exit(0);
+    }
+
+    while(fgets(hash, 256, file)){
+        strcat(buffer, hash);
+        bzero(hash, 256);
+    }
+    pclose(file);
+    printf("%s\n", buffer);
+
+    char res[256];
+
+    char* temp = malloc(3*sizeof(char*));
+
+    temp = strstr(buffer, "SHA256(dh.c)= ") + 14;
+    temp[2] = '\0';
+    printf("%s\n", temp);
+    strcpy(res, temp);
+
+    temp = NULL;
+    free(temp);
+
+    int b1 = 0;
+    int b2 = 0;
+    int b = 0;
+
+
+    if(isalpha(res[0])) {
+		//fix with alpha case
+		 b1 = res[0] - 87;
+  	} else {
+  		//fix with integer case
+  		b1 = res[0] - 48;
+  	}
+    if(isalpha(res[1])) {
+		//fix with alpha case
+		 b2 = res[1] - 87;
+  	} else {
+  		//fix with integer case
+  		b2 = res[1] - 48;
+  	}
+
+    b = (b1*16)+b2;
+
+    printf("%d\n", b);
+
+    bzero(buffer, 256);
+    bzero(res, 256);
+
+    //Assume I am Bob
+  	int Bob_req = compute(g, b, p);
+
+  	sprintf(buffer, "%d\n", Bob_req);
+    n = write(sockfd, buffer, strlen(buffer));
+    printf("%s\n", buffer);
+    if (n < 0)
+    {
+        perror("ERROR writing to socket");
+        exit(0);
+    }
+
+    bzero(buffer, 256);
+
+    n = read(sockfd, buffer, 255);
+    printf("%s\n", buffer);
+    if (n < 0)
+    {
+        perror("ERROR reading from socket");
+        exit(0);
+    }
+    //server is Alice
+  	int Alice_res = atoi(buffer);
+  	int Bob_res_again= compute(Alice_res, b, p);
+
+    bzero(buffer, 256);
+  	sprintf(buffer, "%d\n", Bob_res_again);
+  	n = write(sockfd, buffer, strlen(buffer));
+    printf("%s\n", buffer);
+  	bzero(buffer, 256);
+
+    n = read(sockfd, buffer, 255);
+
+    printf("status report: %s\n", buffer);
+
+    return 0;
+}

hash.txt

+SHA256(dh.c)= e2ee2bf56359a4028d098efd16d996c11fedd74587356f82573f1b2f2029d0ea

project2.c

@@ -40,7 +40,6 @@ int main(int argc, char* argv[]){
     }
 
   //one arguement scenario
-
   if( argc == 2){
     int count = atoi(argv[1]);
     char guess[10];
@@ -58,9 +57,23 @@ int main(int argc, char* argv[]){
   }
 
   //two arguements scenarios
+  if( argc == 3){
+    FILE* test_file;
+    FILE* target_file;
+    test_file = fopen(argv[2],"r");
+    target_file = fopen(argv[3], "rb");
+
+    unsigned char target_harshes[10000][SHA256_BLOCK_SIZE];
+
+    
+
 
 
 
+
+
+  }
+
   return 0;
 
 }

xiaoxuanl4@172.26.37.159

+/*socket programming part comes from comp30023 lab5 sample code.
+  credit to the person who write that sample code*/
+
+
+/* A simple client program for server.c
+
+   To compile: gcc client.c -o client
+
+   To run: start the server, then the client */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <unistd.h>
+
+// Function to compute a^m mod n, comes from www.techiedelight.com
+int compute(int a, int m, int n)
+{
+	int r;
+	int y = 1;
+
+	while (m > 0)
+	{
+		r = m % 2;
+
+		// fast exponention
+		if (r == 1)
+			y = (y*a) % n;
+		a = a*a % n;
+
+		m = m / 2;
+	}
+
+	return y;
+}
+
+
+int main(int argc, char ** argv)
+{
+    int sockfd, portno, n;
+    struct sockaddr_in serv_addr;
+    struct hostent * server;
+
+    char buffer[256];
+
+    portno = 7800;
+
+
+    /* Translate host name into peer's IP address ;
+     * This is name translation service by the operating system
+     */
+    server = gethostbyname("172.26.37.44");
+
+    if (server == NULL)
+    {
+        fprintf(stderr, "ERROR, no such host\n");
+        exit(0);
+    }
+
+    /* Building data structures for socket */
+
+    bzero((char *)&serv_addr, sizeof(serv_addr));
+
+    serv_addr.sin_family = AF_INET;
+
+    bcopy(server->h_addr_list[0], (char *)&serv_addr.sin_addr.s_addr, server->h_length);
+
+    serv_addr.sin_port = htons(portno);
+
+    /* Create TCP socket -- active open
+    * Preliminary steps: Setup: creation of active open socket
+    */
+
+    sockfd = socket(AF_INET, SOCK_STREAM, 0);
+
+    if (sockfd < 0)
+    {
+        perror("ERROR opening socket");
+        exit(0);
+    }
+
+    if (connect(sockfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0)
+    {
+        perror("ERROR connecting");
+        exit(0);
+    }
+
+    /* Do processing
+    */
+
+    //send user name
+
+    bzero(buffer, 256);
+
+    sprintf(buffer, "xiaoxuanl4\n");
+    n = write(sockfd, buffer, strlen(buffer));
+
+    //send g^b(mod p)
+
+    int g=15;
+    int p=97;
+
+    bzero(buffer, 256);
+
+    char command[50];
+	  strcpy(command, "openssl sha256 dh.c > hash.txt" );
+    FILE *fp;
+	  fp = fopen("hash.txt", "r");
+	  while((fgetc(fp) != EOF) && (fgetc(fp) != ' ')) {
+      char first = fgetc(fp);
+  	  char second = fgetc(fp);
+    }
+
+  	int first_num;
+  	int second_num;
+
+    //converting
+    if(isalpha(first)){
+      first_num = first - 87;
+    }
+    else{
+      first_num = first - 48;
+    }
+
+    if(isalpha(second)){
+      second_num = second - 87;
+    }
+    else{
+       second_num = second - 48;
+    }
+    //finally my b value
+  	int b = (first_num * 16) + second_num;
+    //Assume I am Bob
+  	int Bob_req = compute(g, b, p);
+
+  	sprintf(buffer, "%d\n", Bob_req);
+    n = write(sockfd, buffer, strlen(buffer));
+
+    if (n < 0)
+    {
+        perror("ERROR writing to socket");
+        exit(0);
+    }
+
+    bzero(buffer, 256);
+
+    n = read(sockfd, buffer, 255);
+
+    if (n < 0)
+    {
+        perror("ERROR reading from socket");
+        exit(0);
+    }
+    //server is Alice
+  	int Alice_res = atoi(buffer);
+  	int Bob_res_again= compute(Alice_res, b, p);
+
+    bzero(buffer, 256);
+  	sprintf(buffer, "%d\n", Bob_res_again);
+  	n = write(sockfd, buffer, strlen(buffer));
+
+  	bzero(buffer, 256);
+
+    n = read(sockfd, buffer, 255);
+
+    printf("status report: %s\n", buffer);
+
+    return 0;
+}