func pcapWrite(w *pcapgo.Writer, pack chan gopacket.Packet) error {
var err error
for {
packet := <-pack
fmt.Println("receive a package in pcap Write")
err = w.WritePacket(packet.Metadata().CaptureInfo, packet.Data()) // write the payload
if err != nil {
fmt.Println("error in Write File: ", err)
continue
}
fmt.Println("susccessfully write a package")
}
return err
}
func runNGNet(packetSource *gopacket.PacketSource) {
streamFactory := ngnet.NewHttpStreamFactory(eventChan)
pool := tcpassembly.NewStreamPool(streamFactory)
assembler := tcpassembly.NewAssembler(pool)
var pcapWriter *pcapgo.Writer
if *outputPcap != "" {
outPcapFile, err := os.Create(*outputPcap)
if err != nil {
log.Fatalln(err)
}
defer outPcapFile.Close()
pcapWriter = pcapgo.NewWriter(outPcapFile)
pcapWriter.WriteFileHeader(65536, layers.LinkTypeEthernet)
}
var count int = 0
for packet := range packetSource.Packets() {
count++
net_layer := packet.NetworkLayer()
if net_layer == nil {
continue
}
trans_layer := packet.TransportLayer()
if trans_layer == nil {
continue
}
tcp, _ := trans_layer.(*layers.TCP)
if tcp == nil {
continue
}
if pcapWriter != nil {
pcapWriter.WritePacket(packet.Metadata().CaptureInfo, packet.Data())
}
assembler.AssembleWithTimestamp(
net_layer.NetworkFlow(),
tcp,
packet.Metadata().CaptureInfo.Timestamp)
}
assembler.FlushAll()
streamFactory.Wait()
log.Println("Packet count: ", count)
}