Question

接收数据包。

发送数据包后，我也想接收来自前一个数据包目标的数据包。

我尝试使用ReceivePacket，但总是得到packet12的空值。

我还有什么需要做的吗？
设置过滤器。

我查找了pcap.net的文件

我假设参数（“ ip and icmp”）与可在wireshark中使用的过滤器相同。
```
ip.src == 192.168.15.32 and icmp
```
但是此参数有错误。这和wireshark的过滤器不同吗？

代码：

using (PacketCommunicator inputCommunicator =
            selectedInputDevice.Open(65536, // portion of the packet to capture
                                            // 65536 guarantees that the whole packet will be captured on all the link layers
                PacketDeviceOpenAttributes.Promiscuous, // promiscuous mode
                1000)) // read timeout
        {
            using (PacketCommunicator outputCommunicator =
                selectedOutputDevice.Open(100, PacketDeviceOpenAttributes.Promiscuous, 1000))
            {
                // Check the MAC type
                if (inputCommunicator.DataLink != outputCommunicator.DataLink)
                {
                    Console.WriteLine("Warning: the datalink of the capture differs from the one of the selected interface.");
                    Console.WriteLine("Press a key to continue, or CTRL+C to stop.");
                    Console.ReadKey();
                }

                // Allocate a send buffer
                using (PacketSendBuffer sendBuffer = new PacketSendBuffer((uint)capLength))
                {
                    // Fill the buffer with the packets from the file

                    PcapDotNet.Packets.Packet tpacket;
                    while (inputCommunicator.ReceivePacket(out tpacket) ==
                           PacketCommunicatorReceiveResult.Ok)
                    {
                        sendBuffer.Enqueue(tpacket);
                        ++numPackets;
                    }

                    //                        bool isSync = true;

                    // Transmit the queue
                    Stopwatch stopwatch = new Stopwatch();
                    stopwatch.Start();
                    long startTimeMs = stopwatch.ElapsedMilliseconds;
                    Console.WriteLine("Start Time: " + DateTime.Now);

                    Console.ForegroundColor = ConsoleColor.Green;
                    Console.WriteLine("Sending a pcap file is in progress. Wait until it is finished");
                    Console.ResetColor();

                    outputCommunicator.Transmit(sendBuffer, isSync);

                    long endTimeMs = stopwatch.ElapsedMilliseconds;
                    Console.WriteLine("End Time: " + DateTime.Now);
                    long elapsedTimeMs = endTimeMs - startTimeMs;
                    Console.WriteLine("Elapsed Time: " + elapsedTimeMs);

                    Console.WriteLine("Elapsed time: " + elapsedTimeMs + " ms");
                    Console.WriteLine("Total packets generated = " + numPackets);
                    //                        Console.WriteLine("Average packets per second = " + averagePacketsPerSecond);
                    Console.WriteLine("============================================================");

                }
                inputCommunicator.SetFilter("ip and icmp");

                Console.WriteLine("Listening on " + selectedInputDevice.Description + "...");

                PcapDotNet.Packets.Packet packet12;

                inputCommunicator.ReceivePacket(out packet12);

               foreach (var options in packet12)
                    Console.WriteLine(options);

Answer 1

1。

在某一点上，您似乎使用了inputCommunicator

///用文件中的数据包填充缓冲区

但是在另一个地方，您使用相同的inputCommunicator来获取从某个目的地发送的数据包。

似乎您需要使用两个不同的Communicator并使用不同的设备创建它们。

2。

如果遇到错误，请提供错误。

您从何处获得ip.src的语法？您改用了src host吗？

pcap.net ReceivePacket无法正常工作

1 个答案: