路由跟踪程序仿真

1、集美大学计算机工程学院实验报告课程名称：TCP/IP协议与通信程序设计班级：实验成绩：实验项目名称：路由跟踪程序仿真学号：上机实践日期：2016-06-16实验项目编号：13组号：1上机实践时间： 2学时一、 实验目的了解利用原始套接字进行通信程序的编写，编译和执行二、 实验内容与设计思想基于原始套接字编写路由跟踪仿真程序，以跟踪获取本机的 IP 数据包到达集美大学教务处网站服务主机（210.34.129.66）所经历的路由器的IP地址，并在客户端显示出来。提示：本机程序向目标主机发送一个封装ICMP回显请求的数据报，初始化TTL为1，当该包到达途中第一个路由器时，TTL值减为0发生超时错误，

2、第一个路由器反馈源主机ICMP超时差错报文。依次将数据报的TTL值递增1，以便IP包能到达下一个路由器，如法炮制，直到数据报达到目地主机，目地主机将返回ICMP回显应答消息。源主机依次解析处理期间收到的ICMP报文就可以得出数据报从源主机到达目地主机途中所经过的路由器IP。三、 实验使用环境操作系统： Microsoft Windows XP SP2编程环境： Visual C+ 6.0四、实验步骤和调试过程源代码：#define WIN32_LEAN_AND_MEAN #include <winsock2.h> /使用原始套接字需要WinSock2的支持 #include <

3、;ws2tcpip.h> /进行IPPROTO_IP级别设置时用到 #include <stdio.h> #include <stdlib.h> #define ICMP_ECHO 8 /发送Ping请求时的ICMP报文类型 #define ICMP_ECHOREPLY 0 /接收Ping回复时的ICMP报文类型 #define ICMP_TIMEOUT 11 /ICMP超时报文类型 #define ICMP_MIN 8 /Minimum 8-byte ICMP packet (header) #define MAX_PACKET 1024 /Max ICMP p

4、acket size #define DEICMP_PACKSIZE 44 /Defaut ICMP PACKET SIZE char lpdest16; /用来存放目的IP地址 DWORD cStartTickCount; /用来存放发送包的起始时间 #pragma comment( lib, "ws2_32.lib" ) typedef struct _icmphdr /ICMP头部定义，被封装在IP包中 BYTE i_type; /报文类型 BYTE i_code; /代码 USHORT i_cksum; /校验和 USHORT i_id; /标识符 USHORT i

5、_seq; /序号 IcmpHeader; /初始化ICMP头部 void FillICMPData(char *icmp_data,int datasize) IcmpHeader *icmp_hdr=NULL; char *datapart=NULL; icmp_hdr=(IcmpHeader *)icmp_data; icmp_hdr->i_type=ICMP_ECHO; /request an ICMP echo icmp_hdr->i_code=0; icmp_hdr->i_id=(USHORT)GetCurrentProcessId(); icmp_hdr->

6、;i_cksum=0; icmp_hdr->i_seq=0; datapart=icmp_data+sizeof(IcmpHeader); memset(datapart,'E',datasize-sizeof(IcmpHeader); /校验和函数 USHORT checksum(USHORT *buffer,int size) unsigned long cksum=0; while(size>1) cksum+=*buffer+; size-=sizeof(USHORT); if(size) cksum+=*(UCHAR *)buffer; cksum=(ck

7、sum>>16)+(cksum & 0xffff); cksum+=(cksum>>16); return (USHORT)(cksum); int DecodeIPHeader(char *buf,int bytes,struct sockaddr_in *from) IcmpHeader *icmphdr=NULL; DWORD tick; static int icmpcount=1; unsigned short iphdrlen; /判断接收操作是否超时 if(!buf) printf("%2d: *.*.*.* Request timed

8、out.n",icmpcount+); return 1; tick=GetTickCount(); iphdrlen=(buf0 & 0x0f)*4; icmphdr=(IcmpHeader *)(buf+iphdrlen); if(bytes<iphdrlen+ICMP_MIN) printf("Too few bytes from %sn",inet_ntoa(from->sin_addr); return 0; /判断接收的ICMP报文是否为超时报文 if(icmphdr->i_type=ICMP_TIMEOUT&&

9、;icmphdr->i_code=0) printf("%2d: %-15s %4dmsn",icmpcount+,inet_ntoa(from->sin_addr),tick-cStartTickCount); return 0; /判断接收的ICMP报文是否为回复报文 else if(icmphdr->i_type=ICMP_ECHOREPLY&&icmphdr->i_id=GetCurrentProcessId() printf("%2d: %-15s %4dmsn",icmpcount+,inet_ntoa

10、(from->sin_addr),tick-cStartTickCount); printf("Trace complete!n"); return 1; /其他类型,表示不可达 else printf("%2d: Destination host is unreachable!n",icmpcount+); return 1; int main() WSADATA wsaData; SOCKET sockRaw=INVALID_SOCKET; struct sockaddr_in dest, from; int i,bread,fromlen=s

11、izeof(from),timeout=1000,ret; struct hostent *hp=NULL; char *icmp_data=NULL,*recvbuf=NULL; USHORT seq_no=0; printf("输入追踪的目的(IP/主机名):"); scanf("%s",lpdest); if(WSAStartup(MAKEWORD(2,2),&wsaData)!=0) printf("WSAStartup() failed:%dn",GetLastError(); return -1; /创建套接字 s

12、ockRaw=WSASocket(AF_INET,SOCK_RAW,IPPROTO_ICMP,NULL,0,WSA_FLAG_OVERLAPPED); if(sockRaw=INVALID_SOCKET) printf("WSASocket() failed:%dn",WSAGetLastError(); return -1; /对锁定套接字设置超时 bread=setsockopt(sockRaw,SOL_SOCKET,SO_RCVTIMEO,(char *)&timeout,sizeof(timeout); if(bread=SOCKET_ERROR) prin

13、tf("setsockopt(SO_RCVTIMEO) failed:%dn",WSAGetLastError(); return -1; timeout=1000; bread=setsockopt(sockRaw,SOL_SOCKET,SO_SNDTIMEO,(char *)&timeout,sizeof(timeout); if(bread=SOCKET_ERROR) printf("setsockopt(SO_SNDTIMEO) failed:%dn",WSAGetLastError(); return -1; /解析目标地址，将主机名转

14、化为IP地址 memset(&dest,0,sizeof(dest); dest.sin_family=AF_INET; if(dest.sin_addr.S_un.S_addr=inet_addr(lpdest)=INADDR_NONE) if(hp=gethostbyname(lpdest)!=NULL) memcpy(&(dest.sin_addr.S_un.S_addr),hp->h_addr_list0,hp->h_length); dest.sin_family=hp->h_addrtype; printf("dest.sin_addr=

15、%sn",inet_ntoa(dest.sin_addr); else printf("gethostbyname() failed:%dn",WSAGetLastError(); return -1; /Create the ICMP pakcet icmp_data= (char*)HeapAlloc(GetProcessHeap(),HEAP_ZERO_MEMORY,MAX_PACKET); recvbuf = (char*)HeapAlloc(GetProcessHeap(),HEAP_ZERO_MEMORY,MAX_PACKET); if(!icmp_d

16、ata) printf("HeapAlloc() failed: %dn",GetLastError(); return -1; memset(icmp_data,0,MAX_PACKET); FillICMPData(icmp_data,DEICMP_PACKSIZE); printf("跳 IP地址 耗时n"); /开始发送/接收ICMP报文 for(i=1;i<=255;i+) int bwrote; /设置IP包的生存期 ret=setsockopt(sockRaw,IPPROTO_IP,IP_TTL,(char *)&i,size

17、of(int); if(ret=SOCKET_ERROR) printf("setsockopt(IP_TTL) failed:%dn",WSAGetLastError(); (IcmpHeader *)icmp_data)->i_cksum =0; (IcmpHeader *)icmp_data)->i_seq=seq_no+; /Sequence number of ICMP packets (IcmpHeader *)icmp_data)->i_cksum=checksum(USHORT *)icmp_data,DEICMP_PACKSIZE); /

18、发送ICMP包请求查询 cStartTickCount=GetTickCount(); bwrote=sendto(sockRaw,icmp_data,DEICMP_PACKSIZE,0,(struct sockaddr *)&dest,sizeof(dest); if(bwrote=SOCKET_ERROR) if(WSAGetLastError()=WSAETIMEDOUT) printf("timed outn"); continue; printf("sendto() failed:%dn",WSAGetLastError(); return -1; if(bwrote<DEICMP_PACKSIZE) printf("Wrote %d bytesn",bwrote); /接收ICMP回复包 bread=recvfrom(sockRaw,recvbuf,MAX_PACKET,0,(struct sockaddr *)&from,&fromlen); if(bread