remove tshark requirement

[schollz]

package main

import (
    "fmt"
    "log"
    "strings"
    "time"

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

var (
    device       string = "wlx98ded014a3a9"
    snapshot_len int32  = 1024
    promiscuous  bool   = false
    err          error
    timeout      time.Duration = 3 * 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.String())
        address := ""
        rssi := 0
        for _, layer := range packet.Layers() {
            if layer.LayerType() == layers.LayerTypeRadioTap {
                rt := layer.(*layers.RadioTap)
                rssi = int(rt.DBMAntennaSignal)
            } else if layer.LayerType() == layers.LayerTypeDot11 {
                dot11 := layer.(*layers.Dot11)
                addresses := []string{dot11.Address1.String(), dot11.Address2.String(), dot11.Address3.String(), dot11.Address4.String()}
                isOk := false
                tempAddress := ""
                for _, ad := range addresses {
                    if strings.Contains(ad, "ff:ff") {
                        isOk = true
                    } else if len(ad) > 0 {
                        tempAddress = ad
                    }
                }
                if isOk {
                    address = tempAddress
                }
            }
        }
        if address != "" && rssi != 0 {
            fmt.Println(time.Now(), address, rssi)
        }
        // break
    }
}