if (argc >3) { datasize = atoi(argv[3]); if (datasize == 0) datasize = DEF_PACKET_SIZE; if (datasize >1024) /* 用户给出的数据包大小太大 */ { fprintf(stderr,"WARNING : data_size is too large ! "); datasize = DEF_PACKET_SIZE; } } else datasize = DEF_PACKET_SIZE; datasize += sizeof(IcmpHeader);icmp_data = (char*)xmalloc(MAX_PACKET); recvbuf = (char*)xmalloc(MAX_PACKET);if (!icmp_data) { fprintf(stderr,"HeapAlloc failed %d ",GetLastError()); ExitProcess(STATUS_FAILED); } memset(icmp_data,0,MAX_PACKET); fill_icmp_data(icmp_data,datasize);// //显示提示信息 // fprintf(stdout," Pinging %s .... ",dest_ip); for(int i=0;i{ int bwrote;((IcmpHeader*)icmp_data)->i_cksum = 0; ((IcmpHeader*)icmp_data)->timestamp = GetTickCount();((IcmpHeader*)icmp_data)->i_seq = seq_no++; ((IcmpHeader*)icmp_data)->i_cksum = checksum((USHORT*)icmp_data,datasize);

bwrote = sendto(sockRaw,icmp_data,datasize,0,(struct sockaddr*)&dest,sizeof(dest));

if (bwrote == SOCKET_ERROR){ if (WSAGetLastError() == WSAETIMEDOUT) { printf("Request timed out. "); continue; } fprintf(stderr,"sendto failed: %d ",WSAGetLastError()); ExitProcess(STATUS_FAILED); } if (bwrote < datasize ) { fprintf(stdout,"Wrote %d bytes ",bwrote); } bread = recvfrom(sockRaw,recvbuf,MAX_PACKET,0,(struct sockaddr*)&from,&fromlen);

if (bread == SOCKET_ERROR){ if (WSAGetLastError() == WSAETIMEDOUT) { printf("Request timed out. "); continue; } fprintf(stderr,"recvfrom failed: %d ",WSAGetLastError()); ExitProcess(STATUS_FAILED); } if(!decode_resp(recvbuf,bread,&from)) statistic++; /* 成功接收的数目++ */ Sleep(1000);}/* Display the statistic result */ fprintf(stdout," Ping statistics for %s ",dest_ip); fprintf(stdout," Packets: Sent = %d,Received = %d, Lost = %d (%2.0f%% loss) ",times,

statistic,(times-statistic),(float)(times-statistic)/times*100); WSACleanup(); return 0;} /* The response is an IP packet. We must decode the IP header to locate the ICMP data */ int decode_resp(char *buf, int bytes,struct sockaddr_in *from) {IpHeader *iphdr; IcmpHeader *icmphdr; unsigned short iphdrlen;iphdr = (IpHeader *)buf;iphdrlen = (iphdr->h_len) * 4 ; // number of 32-bit words *4 = bytesif (bytes < iphdrlen + ICMP_MIN) {

printf("Too few bytes from %s ",inet_ntoa(from->sin_addr)); }icmphdr = (IcmpHeader*)(buf + iphdrlen);if (icmphdr->i_type != ICMP_ECHOREPLY) { fprintf(stderr,"non-echo type %d recvd ",icmphdr->i_type); return 1; } if (icmphdr->i_id != (USHORT)GetCurrentProcessId()) { fprintf(stderr,"someone else’s packet! "); return 1; } printf("%d bytes from %s:",bytes, inet_ntoa(from->sin_addr)); printf(" icmp_seq = %d. ",icmphdr->i_seq); printf(" time: %d ms ",GetTickCount()-icmphdr->timestamp); printf(" "); return 0;} USHORT checksum(USHORT *buffer, int size) {unsigned long cksum=0;while(size >1) { cksum+=*buffer++; size -=sizeof(USHORT); }if(size) { cksum += *(UCHAR*)buffer; }cksum = (cksum >> 16) + (cksum & 0xffff); cksum += (cksum >>16); return (USHORT)(~cksum); } /* Helper function to fill in various stuff in our ICMP request. */ void fill_icmp_data(char * icmp_data, int datasize){IcmpHeader *icmp_hdr; char *datapart; icmp_hdr = (IcmpHeader*)icmp_data;icmp_hdr->i_type = ICMP_ECHO; icmp_hdr->i_code = 0; icmp_hdr->i_id = (USHORT)GetCurrentProcessId(); icmp_hdr->i_cksum = 0; icmp_hdr->i_seq = 0;datapart = icmp_data + sizeof(IcmpHeader); // // Place some junk in the buffer. // memset(datapart,’E’, datasize - sizeof(IcmpHeader));}/******************* 附: ping命令执行时显示的画面 *************** * C:Documents and Settingshouzhijiang>ping 236.56.54.12 * * * * Pinging 236.56.54.12 with 32 bytes of data: * * * * Request timed out. * * Request timed out. * * Request timed out. * * Request timed out. * * * * Ping statistics for 236.56.54.12: * * Packets: Sent = 4, Received = 0, Lost = 4 (100% loss), * * * *********************************************************//********************************************************* * C:Documents and Settingshouzhijiang>ping 127.0.0.1 * * * * Pinging 127.0.0.1 with 32 bytes of data: * * * * Reply from 127.0.0.1: bytes=32 time<1ms TTL=128 * * Reply from 127.0.0.1: bytes=32 time<1ms TTL=128 * * Reply from 127.0.0.1: bytes=32 time<1ms TTL=128 *

* Reply from 127.0.0.1: bytes=32 time<1ms TTL=128 * * * * Ping statistics for 127.0.0.1: * * Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), * * Approximate round trip times in milli-seconds: * * Minimum = 0ms, Maximum = 0ms, Average = 0ms * * *