2017-2018-1 20155211 《信息安全系统设计基础》第八周学习总结
课下测试一
1 完成家庭作业4.47，4.48，4.49
2 相应代码反汇编成X86-64汇编
3 把上述X86-64汇编翻译成Y86汇编，并给出相应机器码
-
4.47
-
4.48
- 4.49
- 遇到的问题：x86翻译成y86汇编时，运用虚拟机时一直报错，后用在线模拟器时出现了不同的报错。。经查询尚未解决。
课下测试二
把课上练习3的daytime服务器分别用多进程和多线程实现成并发服务器并测试
- 代码如下
- client1.c
#include <netinet/in.h> // for sockaddr_in
#include <sys/types.h> // for socket
#include <sys/socket.h> // for socket
#include <stdio.h> // for printf
#include <stdlib.h> // for exit
#include <string.h> // for bzero
#include <time.h>
#define HELLO_WORLD_SERVER_PORT 6666
#define BUFFER_SIZE 1024
void talk_to_server(char ** argv)
{
//设置一个socket地址结构client_addr,代表客户机internet地址, 端口
struct sockaddr_in client_addr;
bzero(&client_addr,sizeof(client_addr)); //把一段内存区的内容全部设置为0
client_addr.sin_family = AF_INET; //internet协议族
client_addr.sin_addr.s_addr = htons(INADDR_ANY);//INADDR_ANY表示自动获取本机地址
client_addr.sin_port = htons(0); //0表示让系统自动分配一个空闲端口
//创建用于internet的流协议(TCP)socket,用client_socket代表客户机socket
int client_socket = socket(AF_INET,SOCK_STREAM,0);
time_t t;
if( client_socket < 0)
{
printf("Create Socket Failed!
");
exit(1);
}
//把客户机的socket和客户机的socket地址结构联系起来
if( bind(client_socket,(struct sockaddr*)&client_addr,sizeof(client_addr)))
{
printf("Client Bind Port Failed!
");
exit(1);
}//设置一个socket地址结构server_addr,代表服务器的internet地址, 端口
struct sockaddr_in server_addr;
bzero(&server_addr,sizeof(server_addr));
server_addr.sin_family = AF_INET;
if(inet_aton(argv[1],&server_addr.sin_addr) == 0) //服务器的IP地址来自程序的参数
{
printf("Server IP Address Error!
");
exit(1);
}
server_addr.sin_port = htons(HELLO_WORLD_SERVER_PORT);
socklen_t server_addr_length = sizeof(server_addr);
//向服务器发起连接,连接成功后client_socket代表了客户机和服务器的一个socket连接
if(connect(client_socket,(struct sockaddr*)&server_addr, server_addr_length) < 0)
{
printf("Can Not Connect To %s!
",argv[1]);
exit(1);
}
char buffer[BUFFER_SIZE];
bzero(buffer,BUFFER_SIZE);
//从服务器接收数据到buffer中
int length = recv(client_socket,buffer,BUFFER_SIZE,0);
if(length < 0)
{
printf("Recieve Data From Server %s Failed!
", argv[1]);
exit(1);
}
printf("From Server %s : %s
",argv[1],buffer);
length = recv(client_socket,(void *)&t,sizeof(time_t),0);
if(length < 0)
{
printf("Recieve Data From Server %s Failed!
", argv[1]);
exit(1);
}
printf("当前时间： %s
",ctime(&t));
bzero(buffer,BUFFER_SIZE);
//strcpy(buffer,"Thanks!");
//向服务器发送buffer中的数据
send(client_socket,buffer,BUFFER_SIZE,0);
//关闭socket
close(client_socket);
}
int main(int argc, char **argv)
{
if (argc != 2)
{
printf("Usage: .\%s ServerIPAddress
",argv[0]);
exit(1);
}
talk_to_server(argv);
return 0;
}
- server1.c
#include <netinet/in.h> // for sockaddr_in
#include <sys/types.h> // for socket
#include <sys/socket.h> // for socket
#include <stdio.h> // for printf
#include <stdlib.h> // for exit
#include <string.h> // for bzero
#include <unistd.h> // for fork
#include <sys/signal.h> // for signal
#include <sys/wait.h> // for wait
#include <time.h>
#include <arpa/inet.h>
#define HELLO_WORLD_SERVER_PORT 6666
#define LENGTH_OF_LISTEN_QUEUE 20
#define BUFFER_SIZE 1024
void reaper(int sig)
{
int status;
//调用wait3读取子进程的返回值,使zombie状态的子进程彻底释放
while(wait3(&status,WNOHANG,(struct rusage*)0) >=0)
;
}
int main(int argc, char **argv)
{
//设置一个socket地址结构server_addr,代表服务器internet地址, 端口
struct sockaddr_in server_addr;
bzero(&server_addr,sizeof(server_addr)); //把一段内存区的内容全部设置为0
server_addr.sin_family = AF_INET;
server_addr.sin_addr.s_addr = htons(INADDR_ANY);
server_addr.sin_port = htons(HELLO_WORLD_SERVER_PORT);
time_t t;
//创建用于internet的流协议(TCP)socket,用server_socket代表服务器socket
int server_socket = socket(AF_INET,SOCK_STREAM,0);
if( server_socket < 0)
{
printf("Create Socket Failed!
");
exit(1);
}
//把socket和socket地址结构联系起来
if( bind(server_socket,(struct sockaddr*)&server_addr,sizeof(server_addr)))
{
printf("Server Bind Port : %d Failed!
", HELLO_WORLD_SERVER_PORT);
exit(1);
}
//server_socket用于监听
if ( listen(server_socket, LENGTH_OF_LISTEN_QUEUE) )
{
printf("Server Listen Failed!");
exit(1);
}
//通知操作系统,当收到子进程的退出信号(SIGCHLD)时,执行reaper函数,释放zombie状态的进程
(void)signal(SIGCHLD,reaper);
while (1) //服务器端要一直运行
{
//定义客户端的socket地址结构client_addr
struct sockaddr_in client_addr;
socklen_t length = sizeof(client_addr);
//接受一个到server_socket代表的socket的一个连接
//如果没有连接请求,就等待到有连接请求--这是accept函数的特性
//accept函数返回一个新的socket,这个socket(new_server_socket)用于同连接到的客户的通信
//new_server_socket代表了服务器和客户端之间的一个通信通道
//accept函数把连接到的客户端信息填写到客户端的socket地址结构client_addr中
int new_server_socket = accept(server_socket,(struct sockaddr*)&client_addr,&length);
if ( new_server_socket < 0)
{
printf("Server Accept Failed!
");
break;
}
int child_process_pid = fork(); //fork()后,子进程是主进程的拷贝
//在主进程和子进程中的区别是fork()的返回值不同.
if(child_process_pid == 0 )//如果当前进程是子进程,就执行与客户端的交互
{
t=time(NULL);
close(server_socket); //子进程中不需要被复制过来的server_socket
char buffer[BUFFER_SIZE];
bzero(buffer, BUFFER_SIZE);
strcat(buffer,"
"); //C语言字符串连接
//发送buffer中的字符串到new_server_socket,实际是给客户端
send(new_server_socket,buffer,BUFFER_SIZE,0);
printf("服务器实现者学号：20155211
");
printf("客户端IP：%s
",inet_ntoa(client_addr.sin_addr));
printf("当前时间： %s
",ctime(&t));
send(new_server_socket,(void *)&t,sizeof(time_t),0);
bzero(buffer,BUFFER_SIZE);
//接收客户端发送来的信息到buffer中
length = recv(new_server_socket,buffer,BUFFER_SIZE,0);
if (length < 0)
{
printf("Server Recieve Data Failed!
");
exit(1);
}
printf("
%s
",buffer);
//关闭与客户端的连接
close(new_server_socket);
exit(0);
}
else if(child_process_pid > 0) //如果当前进程是主进程
close(new_server_socket); //主进程中不需要用于同客户端交互的new_server_socket
}
//关闭监听用的socket
close(server_socket);
return 0;
}
- 多线程
#include "csapp.h"
#include <time.h>
#include <string.h>
#define MAXRECVLEN 1024
void echo(int connfd)
{
size_t n;
char buf[MAXLINE];
rio_t rio;
time_t ticks = time(NULL);
Rio_readinitb(&rio, connfd);
while((n = Rio_readlineb(&rio, buf, MAXLINE)) != 0) {
/*printf("server received %d bytes
", n);*/
printf("server received %d bytes
，%s",n,buf);
printf("服务器实现人：20155211xxy
当前时间：%.24s
",ctime(&ticks));
snprintf(buf,MAXRECVLEN,"当前时间：%.24s
",ctime(&ticks));
Rio_writen(connfd, buf, n);
}
}
void *thread(void *vargp);
int main(int argc, char **argv)
{
int listenfd, *connfdp, port, clientlen=sizeof(struct sockaddr_in);
struct sockaddr_in clientaddr;
pthread_t tid;
if (argc != 2) {
fprintf(stderr, "usage: %s <port>
", argv[0]);
exit(0);
}
port = atoi(argv[1]);
listenfd = Open_listenfd(port);
while (1) {
connfdp = Malloc(sizeof(int));
*connfdp = Accept(listenfd, (SA *) &clientaddr, &clientlen);
pthread_create(&tid, NULL, thread, connfdp);
}
}
/* thread routine */
void *thread(void *vargp)
{
int connfd = *((int *)vargp);
pthread_detach(pthread_self());
Free(vargp);
echo(connfd);
Close(connfd);
return NULL;
}
- 出现的问题
编译成功后运行时出现如下问题
尚未能解决
课上测试一
- 截图
课上测试三
- 问题如课下测试二