TCP-IP程序设计_II

TCP/IP程序设计汪浩软件学院QQ:641461085引言Internet的应用程序WebServer/WebClientFTPServer/FTPClientMailServer/MailClientDNSServer/DNSClientQQ/eMule/xunlei/MSN/……Sniffer/网络安全工具编写这些Internet应用程序的基础是什么？TCP/IP协议TCP/IP（Socket）程序设计课程目标/内容熟练掌握Windows下的socket编程技术多进程模式TCPSocket程序设计多线程模式TCPSocket程序设计基于select复用模式的TCPSocket程序设计基于WSAAsyncSelect模式的TCPSocket程序设计基于WSAEventSelect模式的TCPSocket程序设计基于Overlapped模式的TCPSocket程序设计基于CompletionPort模式的TCPSocket程序设计WindowsTCPSocket的一些扩充函数以上各I/O模型的UDPSocket程序设计以上各I/O模型的RawSocket程序设计socket选项域名解析C#Socket程序设计OpenSSL的socket程序设计基于WinPcap的数据链路层程序设计教材及参考书TCP/IP协议W.RichardStevensetal.TCP/IPIllustrated,vol1~3(英文).清华大学出版社Socket编程W.RichardStevens.UnixNetworkProgramming(英文),2nd.清华大学出版社；3rd机械工业出版社AnthonyJones，JimOhlund.NetworkProgrammingforMsWindows.2nd.MicrosoftCorporationUnix编程W.RichardStevens,etal.AdvancedProgrammingintheUNIXEnviroment(英文).人民邮电出版社TCP/IP协议族体系结构概述TCP/IP与OSI的对应关系应用层应用层（HTTP/SMTP/POP3/FTP/DNS/SNMP…...）表示层会话层传输层传输层（TCP/UDP）网络层网络层--路由与分片(IP)（ARP/RARP/ICMP/IGMP）数据链路层网络接口层（Ethenet/ATM/FDDI）物理层OSITCP/IPInternet的基础协议是TCP/IP应用协议/程序HTTP—WebServer/WebClientSMTP/POP3—ExchangeServer/Foxmail/OutlookQQ/eMule/迅雷网游、即时通信……传输层（TCP/UDP）提供不同主机进程间的逻辑通信（SocketPairs）Microsoft,SUM,IBM网络层--路由与分片(IP)提供不同主机间的逻辑通信（IPAddr.)Cisco网络接口层（Ethenet/ATM/FDDI）提供连接在同一条链路上的设备间的逻辑通信3COM,D-Linketc编写Internet应用程序—SocketProgrammingGoal:learnhowtobuildclient/serverapplicationthatcommunicateusingsockets语言工具：C++C#JavaWEB应用程序应用程序QQ、eMule、网游应用程序ping应用程序Sniffer应用层WEBServer/WEBClient传输层TCPSocketUDPSocketTCPSocketUDPSocket网络层IPRawSocketIPRawSocketIPRawSocket网络接口层网络接口层网络接口层网络接口层网络接口层applicationtransportnetworkdatalinkphysicalapplicationtransportnetworkdatalinkphysicalnetworkdatalinkphysicalnetworkdatalinkphysicalnetworkdatalinkphysicalnetworkdatalinkphysicalnetworkdatalinkphysicalnetworkdatalinkphysicalnetworkdatalinkphysicalnetworkdatalinkphysicalnetworkdatalinkphysicalnetworkdatalinkphysicalnetworkdatalinkphysicalnetworkdatalinkphysicalnetworkdatalinkphysicalapplicationtransportnetworkdatalinkphysicalapplicationtransportnetworkdatalinkphysical传输层：提供不同主机进程间的逻辑通信套接口Socketpairs(源IP地址,源端口号；目标IP地址，目标端口号)网络层：提供不同主机间的逻辑通信IP地址(源IP地址；目标IP地址)“link”链路层：提供连接在同一条链路上的设备间的逻辑通信ProcessescommunicatingProcess:programrunningwithinahost.withinsamehost,twoprocessescommunicateusinginter-processcommunication(definedbyOS).processesindifferenthostscommunicatebyexchangingmessages(Sockets)Clientprocess:processthatinitiatescommunicationServerprocess:processthatwaitstobecontactedNote:applicationswithP2Parchitectureshaveclientprocesses&serverprocessesInter-processcommunicationofOS(e.g.Unix/Windows)UnixmessagepassingPipesandFIFOsMessagequeuesSynchronizationMutexesandconditionvariablesread-writelockssemaphoresSharedmemoryRemoteprocedurecallsWindowsWaitFunctions(WaitForSingleObjectetc)EventKernelObjectsWaitableTimerKernelObjectsSemaphoreKernelObjectsMutexKernelObjects数据的逐层封装应用层数据应用层数据应用层数据应用层数据TCP/UDP头IP头TCP/UDP头TCP/UDP头IP头物理帧头应用层传输层网络层网络接口层Client/Server编程模型Internet上的所有程序都是C/SC/Svs.B/SASimpleDaytimeClient/Server(IPv4)tcpdaytimecli.cpp/tcpdaytimesrv.cppClientIncludeourownheaderCreateTCPsocketSpecifyserver'sIPaddressandportEstablishconnectionwithserverReadanddisplayserver'sreplyTerminateprogramSocketPairThesocketpairforaTCPconnectionisthefour-tuplethelocalIPaddress,localport,foreignIPaddress,foreignportSocket(TCP/UDP)anIPaddress,aportnumbersourceport#destport#32bitsapplicationdata(variablelength)sequencenumberacknowledgementnumberReceivewindowUrgdatapnterchecksumFSRPAUheadlennotusedOptions(variablelength)Cont.ServerCreateaTCPsocketBindserver'swell-knownporttosocketConvertsockettolisteningsocketAcceptclientconnection,sendreplyTerminateconnectionErrorHandling:WrapperFunctionssockfd=Socket(AF_INET,SOCK_STREAM,0);Beginswithanuppercaseletterlib/wrapsock.cSomeElementSocketFunctionsandDataStructureslonga=0x12345678;0x120x340x560x780x780x560x340x12big-endianlittle-endian低地址高地址ByteOrderingFunctionsTheInternetprotocolsusebig-endianbyteorderingforthesemultibyteintegers--networkbyteorderlow-orderbytehigh-orderbyteAA+1high-orderbytelow-orderbyteAA+1Fourfunctionstoconvertbetweenthesetwobyteordershstandsforhost,nstandsfornetwork,sstandsforshort,lstandsforlong.SomeUsefulFunctionsSocketAddressStructures(1)IPv4SocketAddressStructure#includewinsock2.hIPaddr:192.168.1.1110000001010100000000001000000013232235777unsignedlong提供不同主机间的逻辑通信提供不同主机进程间的逻辑通信套接口Socketpairs/**Basicsystemtypedefinitions,takenfromtheBSDfilesys/types.h.*/typedefunsignedcharu_char;typedefunsignedshortu_short;typedefunsignedintu_int;typedefunsignedlongu_long;/**Thenewtypetobeusedinall*instanceswhichrefertosockets.*/typedefu_intSOCKET;structin_addr{union{struct{u_chars_b1,s_b2,s_b3,s_b4;}S_un_b;struct{u_shorts_w1,s_w2;}S_un_w;u_longS_addr;}S_un;#defines_addrS_un.S_addr/*canbeusedformosttcp&ipcode*/#defines_hostS_un.S_un_b.s_b2/*hostonimp*/#defines_netS_un.S_un_b.s_b1/*network*/#defines_impS_un.S_un_w.s_w2/*imp*/#defines_impnoS_un.S_un_b.s_b4/*imp#*/#defines_l