上机1：基于WinPcap的网络嗅探器设计与实现

上机1：基于WinPcap的网络嗅探器设计与实现上机1：基于WinPcap的网络嗅探器设计1、目的与要求掌握基于WinPcap的网络编程模式。理解并能应用WinPcap设计并实现网络数据包的捕获与解析。2、设备与上机环境连网PC机（至少一台）。计算机硬件要求：IntelPentium5处理器、256MB以上内存，Ethernet网卡，网线若干。计算机软件要求：MSWindows9x/2000/XP操作系统，TCP/IP协议，WinPcap430，Visualc++6.0/.net系统。3、上机内容与步骤：在程序设计之前，请参照提供的软件安装WinPcap。之后，按照如下步骤操作：步骤1：在VC++6.0下创建一个DOS命令行程序，工程名：自己的学号-PacketDump intres; structpcap_pkthdr*header; constu_char*pkt_data; printf("pktdump_ex:printsthepacketsofthenetworkusingWinPcap.\n"); printf("Usage:pktdump_ex[-ssource]\n\n" "Examples:\n" "pktdump_ex-sfile.acp\n" "pktdump_ex-s\\Device\\NPF_{C8736017-F3C3-4373-94AC-9A if(argc<3) { printf("\nNoadapterselected:printingthedevicelist:\n"); /*Theuserdidn'tprovideapacketsource:Retrievethelocaldevicelist*/ if(pcap_findalldevs(&alldevs,errbuf)==-1) { fprintf(stderr,"Errorinpcap_findalldevs_ex:%s\n",errbuf); exit(1); } /*Printthelist*/ for(d=alldevs;d;d=d->next) { printf("%d.%s\n",++i,d->name); if(d->description) printf("(%s)\n",d->description); else printf("(Nodescriptionavailable)\n"); } if(i==0) { printf("\nNointerfacesfound!MakesureWinPcapisinstalled.\n"); return-1; } printf("Entertheinterfacenumber(1-%d):",i); scanf("%d",&inum); if(inum<1||inum>i) { printf("\nInterfacenumberoutofrange.\n"); /*Freethedevicelist*/ pcap_freealldevs(alldevs); return-1; } /*Jumptotheselectedadapter*/ for(d=alldevs,i=0;i<inum-1;d=d->next,i++); /*Opentheadapter*/ if((fp=pcap_open_live(d->name, //nameofthedevice 65536, //portionofthepackettocapture. //65536grantsthatthewholepacketwillbecapturedonalltheMACs. 1, //promiscuousmode(nonzeromeanspromiscuous) 1000, //readtimeout errbuf //errorbuffer ))==NULL) { fprintf(stderr,"\nErroropeningadapter\n"); return-1; } } else { /*Donotcheckfortheswitchtype('-s')*/ if((fp=pcap_open_live(argv[2], //nameofthedevice 65536, //portionofthepackettocapture. //65536grantsthatthewholepacketwillbecapturedonalltheMACs. 1, //promiscuousmode(nonzeromeanspromiscuous) 1000, //readtimeout errbuf //errorbuffer ))==NULL) { fprintf(stderr,"\nErroropeningadapter\n"); return-1; } } /*Readthepackets*/ while((res=pcap_next_ex(fp,&header,&pkt_data))>=0) { if(res==0) /*Timeoutelapsed*/ continue; /*printpkttimestampandpktlen*/ printf("%ld:%ld(%ld)\n",header->ts.tv_sec,header->ts.tv_usec,header->len); /*Printthepacket*/ for(i=1;(i<header->caplen+1);i++) { printf("%.2x",pkt_data[i-1]); if((i%LINE_LEN)==0)printf("\n"); } printf("\n\n"); } if(res==-1) { printf("Errorreadingthepackets:%s\n",pcap_geterr(fp)); return-1; } pcap_close(fp); return0;步骤3：为编译器指定包含文件和库文件搜索目录。假定WinPcap开发包WpdPack_4_0_2.zip被解压缩到C盘，如下图：为编译器指定包含文件和库文件搜索目录的方法如下：在VC++6.0下，打开Tools菜单，选择Options，然后选择Directories选项卡，指定WinPcap包含文件和库文件目录，如下图所示。步骤4：指定链接的库文件。方法：打开Project菜单，