linux网络编程课程设计报告

-.z.《Linu*网络编程》课程设计班级：：指导老师：一、设计背景Linu*操作系统作为一个开源的操作系统被越来越多的人所应用，它的好处在于操作系统源代码的公开化！只要是基于GNU公约的软件你都可以任意使用并修改它的源代码。通过这次课程设计能更好的学习网络编程知识和掌握LINU*平台上应用程序设计开发的过程，将大学四年所学知识综合运用，为未来的工作学习打下基础。二、设计目的1、学习epoll跟FTP被动模式2、掌握linu*基本命令，例如ls、cd、login；3、学会如何编译、运行三、环境要求1、centos64位操作系统2、gcc编译器四、设计原理4．1客户端客户端程序的主要任务有以下3个：（1）、分析用户输入的命令。（2）、根据命令向服务器发出请求（3）、接受服务器返回请求的结果客户端为用户提供了3种命令：（1）、get:从服务器下载文件（2）、list:列出客户端当前目录的容（3）、quit离开4.2服务器端（1）、分析请求代码。（2）、根据请求代码做相应的处理（3）、等待返回结果或者应答信息五、软件测试结果六、部分主代码*include"ftserve.h"intmain(intargc,char*argv[]){ intsock_listen,sock_control,port,pid; if(argc!=2){ printf("usage:./ftserveport\n"); e*it(0); } port=atoi(argv[1]); //createsocket if((sock_listen=socket_create(port))<0){ perror("Errorcreatingsocket"); e*it(1); } while(1){ //waitforclientrequest //createnewsocketforcontrolconnection if((sock_control=socket_accept(sock_listen)) <0) break; //createchildprocesstodoactualfiletransfer if((pid=fork())<0){ perror("Errorforkingchildprocess"); }elseif(pid==0){ close(sock_listen); ftserve_process(sock_control); close(sock_control); e*it(0); } close(sock_control); } close(sock_listen); return0;}/***Sendfilespecifiedinfilenameoverdataconnection,sending*controlmessageovercontrolconnection*Handlescaseofnullorinvalidfilename*/voidftserve_retr(intsock_control,intsock_data,char*filename){ FILE*fd=NULL; chardata[MA*SIZE]; size_tnum_read; fd=fopen(filename,"r"); if(!fd){ //senderrorcode(550Requestedactionnottaken) send_response(sock_control,550); }else{ //sendokay(150Filestatusokay) send_response(sock_control,150); do{ num_read=fread(data,1,MA*SIZE,fd); if(num_read<0){ printf("errorinfread()\n"); } //sendblock if(send(sock_data,data,num_read,0)<0) perror("errorsendingfile\n"); }while(num_read>0); //sendmessage:226:closingconn,filetransfersuccessful send_response(sock_control,226); fclose(fd); }}/***Sendlistoffilesincurrentdirectory*overdataconnection*Return-1onerror,0onsuccess*/intftserve_list(intsock_data,intsock_control){ chardata[MA*SIZE]; size_tnum_read; FILE*fd; intrs=system("ls-l|tail-n+2>tmp.t*t"); if(rs<0){ e*it(1); } fd=fopen("tmp.t*t","r"); if(!fd){ e*it(1); } /*Seektothebeginningofthefile*/ fseek(fd,SEEK_SET,0); send_response(sock_control,1);//starting memset(data,0,MA*SIZE); while((num_read=fread(data,1,MA*SIZE,fd))>0){ if(send(sock_data,data,num_read,0)<0){ perror("err"); } memset(data,0,MA*SIZE); } fclose(fd); send_response(sock_control,226); //send226 return0; }/***Opendataconnectiontoclient*Returns:socketfordataconnection*or-1onerror*/intftserve_start_data_conn(intsock_control){ charbuf[1024]; intwait,sock_data; //Waitforgo-aheadoncontrolconn if(recv(sock_control,&wait,sizeofwait,0)<0){ perror("Errorwhilewaiting"); return-1; } //Getclientaddress structsockaddr_inclient_addr; socklen_tlen=sizeofclient_addr; getpeername(sock_control,(structsockaddr*)&client_addr,&len); inet_ntop(AF_INET,&client_addr.sin_addr,buf,sizeof(buf)); //Initiatedataconnectionwithclient if((sock_data=socket_connect(CLIENT_PORT_ID,buf))<0) return-1; returnsock_data; }/***Authenticateauser'scredentials*Return1ifauthenticated,0ifnot*/intftserve_check_user(char*user,char*pass){ charusername[MA*SIZE]; charpassword[MA*SIZE]; char*pch; charbuf[MA*SIZE]; char*line=NULL; size_tnum_read; size_tlen=0; FILE*fd; intauth=0; fd=fopen(".auth","r"); if(fd==NULL){ perror("filenotfound"); e*it(1); } while((num_read=getline(&line,&len,fd))!=-1){ memset(buf,0,MA*SIZE); strcpy(buf,line); pch=strtok(buf,""); strcpy(username,pch); if(pch!=NULL){ pch=strtok(NULL,""); strcpy(password,pch); } //removeendoflineandwhitespace trimstr(password,(int)strlen(password)); if((strcmp(user,username)==0)&&(strcmp(pass,password)==0)){ auth=1; break; } } free(line); fclose(fd); returnauth;}/***Loginconnectedclient*/intftserve_login(intsock_control){ charbuf[MA*SIZE]; charuser[MA*SIZE]; charpass[MA*SIZE]; memset(user,0,MA*SIZE); memset(pass,0,MA*SIZE); memset(buf,0,MA*SIZE); //Waittorecieveusername if((recv_data(sock_control,buf,sizeof(buf)))==-1){ perror("recverror\n"); e*it(1); } inti=5; intn=0; while(buf[i]!=0) user[n++]=buf[i++]; //tellclientwe'rereadyforpassword send_response(sock_control,331); //Waittorecievepassword memset(buf,0,MA*SIZE); if((recv_data(sock_control,buf,sizeof(buf)))==-1){ perror("recverror\n"); e*it(1); } i=5; n=0; while(buf[i]!=0){ pass[n++]=buf[i++]; } return(ftserve_check_user(user,pass));}/***Waitformandfromclientand*sendresponse*Returnsresponsecode*/intftserve_recv_cmd(intsock_control,char*cmd,char*arg){ intrc=200; charbuffer[MA*SIZE]; memset(buffer,0,MA*SIZE); memset(cmd,0,5); memset(arg,0,MA*SIZE); //Waittorecievemand if((recv_data(sock_control,buffer,sizeof(buffer)))==-1){ perror("recverror\n"); return-1; } strncpy(cmd,buffer,4); char*tmp=buffer+5; strcpy(arg,tmp); if(strcmp(cmd,"QUIT")==0){ rc=221; }elseif((strcmp(cmd,"USER")==0)||(strcmp(cmd,"PASS")==0)|| (strcmp(cmd,"LIST")==0)||(strcmp(cmd,"RETR")==0)){ rc=200; }else{//invalidmand rc=502; } send_response(sock_control,rc); returnrc;}/***Childprocesshandlesconnectiontoclient*/voidftserve_process(intsock_control){ intsock_data; charcmd[5]; chararg[MA*SIZE]; //Sendwelemessage send_response(sock_control,220); //Authenticateuser if(ftserve_login(sock_control)==1){ send_response(sock_control,230); }else{ send_response(sock_control,430)