微軟ping程序源代碼完整版(下)

if (argc >3)
    {
    datasize = atoi(argv[3]);
    if (datasize == 0)
    datasize = DEF_PACKET_SIZE;
    if (datasize >1024) /* 用戶給出的數(shù)據(jù)包大小太大 */
    {
    fprintf(stderr,"WARNING : data_size is too large !\n");
    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\n",GetLastError());
    ExitProcess(STATUS_FAILED);
    }
    memset(icmp_data,0,MAX_PACKET);
    fill_icmp_data(icmp_data,datasize);
    //
    //顯示提示信息
    //
    fprintf(stdout,"\nPinging %s ....\n\n",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.\n");
    continue;
    }
    fprintf(stderr,"sendto failed: %d\n",WSAGetLastError());
    ExitProcess(STATUS_FAILED);
    }
    if (bwrote < datasize ) {
    fprintf(stdout,"Wrote %d bytes\n",bwrote);
    }
    bread = recvfrom(sockRaw,recvbuf,MAX_PACKET,0,(struct sockaddr*)&from,&fromlen);
    if (bread == SOCKET_ERROR){
    if (WSAGetLastError() == WSAETIMEDOUT) {
    printf("Request timed out.\n");
    continue;
    }
    fprintf(stderr,"recvfrom failed: %d\n",WSAGetLastError());
    ExitProcess(STATUS_FAILED);
    }
    if(!decode_resp(recvbuf,bread,&from))
    statistic++; /* 成功接收的數(shù)目++ */
    Sleep(1000);
    }
    /*
    Display the statistic result
    */
    fprintf(stdout,"\nPing statistics for %s \n",dest_ip);
    fprintf(stdout," Packets: Sent = %d,Received = %d, Lost = %d (%2.0f%% loss)\n",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 = bytes
    if (bytes < iphdrlen + ICMP_MIN) {
    printf("Too few bytes from %s\n",inet_ntoa(from->sin_addr));
    }
    icmphdr = (IcmpHeader*)(buf + iphdrlen);
    if (icmphdr->i_type != ICMP_ECHOREPLY) {
    fprintf(stderr,"non-echo type %d recvd\n",icmphdr->i_type);
    return 1;
    }
    if (icmphdr->i_id != (USHORT)GetCurrentProcessId()) {
    fprintf(stderr,"someone else's packet!\n");
    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("\n");
    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命令執(zhí)行時顯示的畫面 ***************\
    * C:\Documents and Settings\houzhijiang>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 Settings\houzhijiang>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 *
    * *