golang使用gopacket包进行数据包捕获实践（未成功）

想用go抓TCP包，参考：https://www.cnblogs.com/lanyangsh/p/9821106.html，结果运行时提示wpcap.dll有问题，从网上下载了几个都不行。后来安装了win10Pcap，似乎可以了。但又提示：Error opening adapter: ��ɹ��ɡ� (0)

改为参考：https://blog.csdn.net/warrior_0319/article/details/83150408

1、获取所有的网络设备信息，代码：

package main

import (
    "fmt"
    "log"

    "github.com/google/gopacket/pcap"
)

func main() {
    // Find all devices
    devices, err := pcap.FindAllDevs()
    if err != nil {
        log.Fatal(err)
    }

    // Print device information
    fmt.Println("Devices found:")
    for _, device := range devices {
        fmt.Println("\nName: ", device.Name)
        fmt.Println("Description: ", device.Description)
        fmt.Println("Devices addresses:", device.Description)
        for _, address := range device.Addresses {
            fmt.Println("- IP address: ", address.IP)
            fmt.Println("- Subnet mask: ", address.Netmask)
        }
    }
}

2 打开设备实时捕捉，代码：

package main

import (
    "fmt"
    "log"
    "time"

    "github.com/google/gopacket"
    "github.com/google/gopacket/pcap"
)

var (
    device       string = "eth0"
    snapshot_len int32  = 1024
    promiscuous  bool   = false
    err          error
    timeout      time.Duration = 30 * time.Second
    handle       *pcap.Handle
)

func main() {
    // Open device
    handle, err = pcap.OpenLive(device, snapshot_len, promiscuous, timeout)
    if err != nil {
        log.Fatal(err)
    }
    defer handle.Close()

    // Use the handle as a packet source to process all packets
    packetSource := gopacket.NewPacketSource(handle, handle.LinkType())
    for packet := range packetSource.Packets() {
        // Process packet here
        fmt.Println(packet)
    }
}

然而，运行时再次遇到： Error opening adapter: ��ɹ��ɡ� (0)，感觉还是Pcap的问题，从https://www.winpcap.org/install/default.htm官网重新下载安装，还不行。

3 抓取结果保存为pcap格式文件

package main

import (
    "fmt"
    "os"
    "time"

    "github.com/google/gopacket"
    "github.com/google/gopacket/layers"
    "github.com/google/gopacket/pcap"
    "github.com/google/gopacket/pcapgo"
)

var (
    deviceName  string = "eth0"
    snapshotLen uint32 = 1024
    promiscuous bool   = false
    err         error
    timeout     time.Duration = -1 * time.Second
    handle      *pcap.Handle
    packetCount int = 0
)

func main() {
    // Open output pcap file and write header
    f, _ := os.Create("test.pcap")
    w := pcapgo.NewWriter(f)
    w.WriteFileHeader(snapshotLen, layers.LinkTypeEthernet)
    defer f.Close()

    // Open the device for capturing
    handle, err = pcap.OpenLive(deviceName, int32(snapshotLen), promiscuous, timeout)
    if err != nil {
        fmt.Printf("Error opening device %s: %v", deviceName, err)
        os.Exit(1)
    }
    defer handle.Close()

    // Start processing packets
    packetSource := gopacket.NewPacketSource(handle, handle.LinkType())
    for packet := range packetSource.Packets() {
        // Process packet here
        fmt.Println(packet)
        w.WritePacket(packet.Metadata().CaptureInfo, packet.Data())
        packetCount++

        // Only capture 100 and then stop
        if packetCount > 100 {
            break
        }
    }
}