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C-/C++-Quelltext

void Pinger::PingIP(unsigned int ip)
{
    const int SIZE = sizeof(ETH_HDR) + sizeof(IP_HDR) + sizeof(ICMP_HDR);
    unsigned char aPacket[SIZE];
    ZeroMemory(aPacket, SIZE);

    ETH_HDR* eth = (ETH_HDR*)aPacket;
    IP_HDR* ip_hdr = (IP_HDR*)(aPacket + sizeof(ETH_HDR));
    ICMP_HDR* icmp = (ICMP_HDR*)(aPacket + sizeof(IP_HDR) + sizeof(ETH_HDR));

    // Get destination MAC address
    unsigned char aMAC[MAC_LEN];
    m_pCore->GetMAC(ip, aMAC);

    memcpy(eth->aDstMac, aMAC, MAC_LEN);
    memcpy(eth->aSrcMac, m_pCore->m_aLocalMAC, MAC_LEN);
    eth->PType = PROTO_IP;

    ip_hdr->Version = 4;
    ip_hdr->IHL = sizeof(IP_HDR) / sizeof(unsigned long);
    ip_hdr->DSCP = 0;
    ip_hdr->ECN = 1;
    ip_hdr->Length = htons(SIZE - sizeof(ETH_HDR));
    ip_hdr->ID = 0;
    ip_hdr->Flags = DF; // 010, DF
    ip_hdr->FragOffset = 0;
    ip_hdr->TTL = 128;
    ip_hdr->Protocol = IPPROTO_ICMP;
    ip_hdr->Checksum = 0;
    ip_hdr->SourceIP = m_pCore->m_LocalIP;
    ip_hdr->DestIP = ip;

    ip_hdr->Checksum = Checksum((unsigned short*)ip_hdr, sizeof(IP_HDR));

    icmp->Type = ICMP_ECHO;
    icmp->Code = 0;
    icmp->Checksum = 0;
    icmp->RoH = 0;

    icmp->Checksum = Checksum((unsigned short*)icmp, sizeof(ICMP_HDR));
    
    // Send packet
    if (pcap_sendpacket(m_pCore->m_pDeviceHandle, (const unsigned char*)aPacket, SIZE) != NO_ERROR)
        std::cout << "Error sending ping (icmp) packet: " << pcap_geterr(m_pCore->m_pDeviceHandle) << std::endl;
    else
    {
        pingedIPs.push_back(ip);
    }
}