121 lines
3.1 KiB
Go
121 lines
3.1 KiB
Go
package main
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import (
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"fmt"
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"log"
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"net"
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"os"
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"os/signal"
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"syscall"
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"github.com/google/gopacket"
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"github.com/google/gopacket/layers"
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"github.com/google/gopacket/pcap"
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"github.com/google/gopacket/pcapgo"
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)
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// 打印可用的网络接口信息
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func printAvailableInterfaces() {
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devices, err := pcap.FindAllDevs()
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if err != nil {
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log.Fatal(err)
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}
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fmt.Println("可用的网络接口:")
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for _, device := range devices {
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fmt.Printf("名称: %s\n描述: %s\n地址: %+v\n\n", device.Name, device.Description, device.Addresses)
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}
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}
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// 判断 IP 是否在链表中
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func isIPInList(ip net.IP) bool {
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for e := IpList.Front(); e != nil; e = e.Next() {
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if e.Value.(net.IP).Equal(ip) {
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return true
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}
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}
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return false
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}
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// 打印捕获到的每个数据包的信息
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func printPacketInfo(packet gopacket.Packet) {
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ipLayer := packet.Layer(layers.LayerTypeIPv4)
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if ipLayer != nil {
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ip, _ := ipLayer.(*layers.IPv4)
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IpMutex.Lock()
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defer IpMutex.Unlock()
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if !isIPInList(ip.SrcIP) {
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IpList.PushBack(ip.SrcIP)
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log.Printf("\033[31m 已添加源 IP: %s 到链表 \033[0m\n", ip.SrcIP)
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}
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}
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}
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// startPacketCapture 启动数据包捕获
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func startPacketCapture() {
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// 打开指定的网络接口进行实时数据包捕获
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handle, err := pcap.OpenLive(*InterfaceName, 65535, true, pcap.BlockForever)
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if err != nil {
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log.Fatalf("打开网络接口 %s 出错: %v", *InterfaceName, err)
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}
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// 确保在函数退出时关闭句柄，释放资源
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defer func() {
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fmt.Println("清理资源...")
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if handle != nil {
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handle.Close()
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}
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}()
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// 设置 BPF（Berkeley Packet Filter）过滤器，以便只捕获指定协议的数据包
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err = handle.SetBPFFilter(*Protocol)
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if err != nil {
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log.Fatalf("设置 BPF 过滤器出错: %v", err)
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}
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// 如果指定了输出文件，则创建文件并初始化 pcapgo.Writer
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var pcapWriter *pcapgo.Writer
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if *PcapFile != "" {
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file, err := os.Create(*PcapFile)
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if err != nil {
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log.Fatalf("创建输出文件出错: %v", err)
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}
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defer file.Close()
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pcapWriter = pcapgo.NewWriter(file)
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// 写入 pcap 文件头部，指定最大捕获长度和链路层类型
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err = pcapWriter.WriteFileHeader(65535, layers.LinkTypeEthernet)
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if err != nil {
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log.Fatalf("写入全局头部出错: %v", err)
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}
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}
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// 创建数据包源，用于从网络接口读取数据包
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packetSource := gopacket.NewPacketSource(handle, handle.LinkType())
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fmt.Printf("正在监听网络接口 %s, 使用过滤器 '%s'...\n", *InterfaceName, *Protocol)
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// 创建信号通道，用于捕获中断信号
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sigChan := make(chan os.Signal, 1)
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signal.Notify(sigChan, os.Interrupt, syscall.SIGTERM)
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// 启动一个 goroutine 来处理捕获到的数据包
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go func() {
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for packet := range packetSource.Packets() {
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// 打印数据包信息
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printPacketInfo(packet)
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// 如果指定了输出文件，则将数据包写入文件
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if pcapWriter != nil {
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err := pcapWriter.WritePacket(packet.Metadata().CaptureInfo, packet.Data())
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if err != nil {
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log.Printf("写入数据包出错: %v", err)
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}
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}
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}
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}()
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// 等待中断信号，收到信号后停止捕获
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<-sigChan
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fmt.Println("\n停止抓包...")
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}
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