Golang pcap.OpenOffline函數代碼示例

func runTestZone(){
	fmt.Println("We're in test zone")
	if handle, err := pcap.OpenOffline("/home/jnankin/Desktop/test.pcap"); err != nil {
		panic(err)
	} else {
		packetSource := gopacket.NewPacketSource(handle, handle.LinkType())
		for packet := range packetSource.Packets() {
			
			if packet.Layer(layers.LayerTypeTCP) != nil {
				appLayer := packet.ApplicationLayer()
				fmt.Println("APP LAYER: \n" + string(appLayer.Payload()) + "\n\n");
				
				sipMessage := sipparser.ParseMsg(string(appLayer.Payload()))
				fmt.Println("SIP BODY: \n" + sipMessage.Body + "\n\n");
				fmt.Println("Content length: \n" + sipMessage.ContentLength + "\n\n");
				
				/*SIP PDU detection: 1st Line contains SIP/2.0

foreach line, if it's a content length, set it.
    add each line to the current sip message
    if the line is blank:
        if I have a content length:
         add content length more bytes from the message to the current sip message
        
        add the current message to the list of messages found

if there are still messages in the buffer, the packet is fragmented and we need more messages

				*/
			}
		}
	}
}

func NewPcapFileSniffer(filename string) (*PcapHandle, error) {
	pcapFileHandle, err := pcap.OpenOffline(filename)
	pcapHandle := PcapHandle{
		handle: pcapFileHandle,
	}
	return &pcapHandle, err
}

func (c *cmdBenchmark) ParsingFinished() (err error) {
	if !c.shouldExecute {
		return
	}
	handle, err := pcap.OpenOffline(c.InputFileName)
	errs.CheckE(err)
	defer handle.Close()

	bo := packet.NewBufferedObtainer(handle)

	var pp packet.Processor
	if c.ProcCopy {
		pp = processor.NewCopyingProcessor()
	} else {
		pp = processor.NewReusingProcessor()
	}
	pp.SetObtainer(bo)

	var totalDuration time.Duration
	for i := 0; i < c.Iter; i++ {
		bo.Reset()
		start := time.Now()
		pp.ProcessAll()
		duration := time.Since(start)
		totalDuration += duration
	}
	timePerPacket := totalDuration / time.Duration(c.Iter*bo.Packets())
	fmt.Printf("total duration: %s, time/pkt: %s\n", totalDuration, timePerPacket)
	return
}

func TestTCP(t *testing.T) {
	handle, err := pcap.OpenOffline("tcptest.pcap")
	if err != nil {
		panic(err)
	}
	packetSource := gopacket.NewPacketSource(handle, handle.LinkType())
	defer handle.Close()
	tcpPack := make(chan gopacket.Packet, 10)
	nomalPack := make(chan gopacket.Packet, 5)
	for input_pack := range packetSource.Packets() { // send tcp package for channel
		tcpLayer := input_pack.Layer(layers.LayerTypeTCP)
		if tcpLayer != nil {
			tcpPack <- input_pack
			// send packet to tcp ASSEMBLER
		}
	}
	streamFactory := &DNSStreamFactory{normal: nomalPack}
	streamPool := tcpassembly.NewStreamPool(streamFactory)
	assembler := tcpassembly.NewAssembler(streamPool)
	go tcpAssemble(tcpPack, assembler)
	pack := <-nomalPack
	udpLayer := pack.Layer(layers.LayerTypeUDP)
	if udpLayer == nil {
		t.Errorf("can not fine udp Layer in result")
	}
	dns_message := new(dns.Msg)
	err = dns_message.Unpack(udpLayer.LayerPayload())
	if err != nil {
		t.Errorf("can not parse dns message")
	}
	fmt.Printf(dns_message.String())
}

func packetSource() *gopacket.PacketSource {
	if *inputPcap != "" {
		handle, err := pcap.OpenOffline(*inputPcap)
		if err != nil {
			log.Fatalln(err)
		}
		fmt.Printf("open pcap file \"%s\"\n", *inputPcap)
		return gopacket.NewPacketSource(handle, handle.LinkType())
	}

	if *device == "" {
		*device = autoSelectDev()
		if *device == "" {
			log.Fatalln("no device to capture")
		}
	}

	handle, err := pcap.OpenLive(*device, 1024*1024, true, pcap.BlockForever)
	if err != nil {
		log.Fatalln(err)
	}
	if *bpf != "" {
		if err = handle.SetBPFFilter(*bpf); err != nil {
			log.Fatalln("Failed to set BPF filter:", err)
		}
	}
	fmt.Printf("open live on device \"%s\", bpf \"%s\", serves on port %d\n", *device, *bpf, *bindingPort)
	return gopacket.NewPacketSource(handle, handle.LinkType())
}

func main() {
	flag.Parse()

	pcap, err := pcap.OpenOffline(*pcapFile)
	if err != nil {
		fmt.Fprintln(os.Stderr, "error opening pcap file:", err)
		os.Exit(1)
	}
	h := mongocaputils.NewPacketHandler(pcap)
	m := mongocaputils.NewMongoOpStream(*packetBufSize)

	ch := make(chan struct{})
	go func() {
		defer close(ch)
		for op := range m.Ops {
			if _, ok := op.Op.(*mongoproto.OpUnknown); !ok {
				fmt.Printf("%f %v\n", float64(op.Seen.Sub(m.FirstSeen))/10e8, op)
			}
		}
	}()

	if err := h.Handle(m, -1); err != nil {
		fmt.Fprintln(os.Stderr, "mongocapcat: error handling packet stream:", err)
	}
	<-ch
}

func TestNgnet(t *testing.T) {
	eventChan := make(chan interface{}, 1024)
	f := NewHttpStreamFactory(eventChan)
	pool := tcpassembly.NewStreamPool(f)
	assembler := tcpassembly.NewAssembler(pool)
	packetCount := 0
	fmt.Println("Run")
	if handle, err := pcap.OpenOffline("dump.pcapng"); err != nil {
		panic(err)
	} else {
		packetSource := gopacket.NewPacketSource(handle, handle.LinkType())
		for packet := range packetSource.Packets() {
			net_layer := packet.NetworkLayer()
			trans_layer := packet.TransportLayer()

			if net_layer == nil {
				continue
			}
			if trans_layer == nil {
				continue
			}
			packetCount++
			tcp, _ := trans_layer.(*layers.TCP)
			assembler.AssembleWithTimestamp(net_layer.NetworkFlow(), tcp, packet.Metadata().CaptureInfo.Timestamp)
		}
	}
	assembler.FlushAll()
	f.Wait()
	fmt.Println("packet:", packetCount, "http:", len(eventChan))
}

func ProcessPackets(pcapFile string,
	mongodHost string,
	mongodPort string) {
	if handle, err := pcap.OpenOffline(pcapFile); err != nil {
		panic(err)
	} else {
		var connectionWaitGroup sync.WaitGroup
		packetSource := gopacket.NewPacketSource(handle, handle.LinkType())
		firstPacket := <-packetSource.Packets()
		packetMinTimestamp = GetPacketTime(firstPacket)
		mapHostConnection = make(map[string]*MongoConnection)
		SendPacket(firstPacket,
			&connectionWaitGroup,
			mongodHost,
			mongodPort)
		for packet := range packetSource.Packets() {
			SendPacket(packet,
				&connectionWaitGroup,
				mongodHost,
				mongodPort)
		}
		for _, mConnection := range mapHostConnection {
			mConnection.EOF()
		}
		connectionWaitGroup.Wait()
	}
}

//init re-initializes a snifer for uses
func (s *Snifer) init() error {
	var handle *pcap.Handle
	var err error

	if s.conf.Offline {
		handle, err = pcap.OpenOffline(s.source)
		checkError(err, fmt.Sprintf("Create offline handle %s", s.source))
	} else {
		handle, err = pcap.OpenLive(s.source, s.conf.MaxPacket, s.conf.Promod, s.conf.Timeout)
		checkError(err, fmt.Sprintf("Create Live handle %s", s.source))

		if err == nil {
			err = handle.SetBPFFilter(s.conf.Filter)
			checkError(err, fmt.Sprintf("Setting BPFFilter %s: %s", s.source, s.conf.Filter))
		}

	}

	if err != nil {
		checkError(err, fmt.Sprintf("Creating Snifer for %s", s.source))
		return err
	}

	s.handle = handle
	log.Printf("Snifer: Handler created and ready!")

	return nil
}

func pcapInfo(filename string) (start time.Time, end time.Time, packets int, size int) {
	handleRead, err := pcap.OpenOffline(*fname)
	if err != nil {
		log.Fatal("PCAP OpenOffline error (handle to read packet):", err)
	}

	var previousTs time.Time
	var deltaTotal time.Duration

	for {
		data, ci, err := handleRead.ReadPacketData()
		if err != nil && err != io.EOF {
			log.Fatal(err)
		} else if err == io.EOF {
			break
		} else {

			if start.IsZero() {
				start = ci.Timestamp
			}
			end = ci.Timestamp
			packets++
			size += len(data)

			if previousTs.IsZero() {
				previousTs = ci.Timestamp
			} else {
				deltaTotal += ci.Timestamp.Sub(previousTs)
				previousTs = ci.Timestamp
			}
		}
	}
	fmt.Printf("Avg packet rate %d/s\n", packets/int(deltaTotal.Seconds()))
	return start, end, packets, size
}

func main() {
	flag.Parse()
	var handle *pcap.Handle
	var err error
	if *fname != "" {
		log.Printf("Reading from pcap dump %q", *fname)
		handle, err = pcap.OpenOffline(*fname)
	} else {
		log.Printf("Starting capture on interface %q", *iface)
		handle, err = pcap.OpenLive(*iface, int32(*snaplen), true, pcap.BlockForever)
	}
	if err != nil {
		log.Fatal(err)
	}

	if err := handle.SetBPFFilter(*filter); err != nil {
		log.Fatal(err)
	}

	packetSource := gopacket.NewPacketSource(handle, handle.LinkType())
	for packet := range packetSource.Packets() {
		if packet == nil {
			return
		}
		if udpLayer := packet.Layer(layers.LayerTypeUDP); udpLayer != nil {
			udp, _ := udpLayer.(*layers.UDP)
			fwdSIPPacket(udp.BaseLayer.Payload)
		}
	}
}

func main() {
	if len(os.Args) != 2 {
		fmt.Printf("Usage: %s pcap\n", os.Args[0])
		os.Exit(0)
	}

	input, output := os.Args[1], "out.ts"

	handle, err := pcap.OpenOffline(input)
	if err != nil {
		log.Fatal(err)
	}
	defer handle.Close()

	f, err := os.Create(output)
	if err != nil {
		log.Fatal(err)
	}
	defer f.Close()

	source := gopacket.NewPacketSource(handle, handle.LinkType())
	for packet := range source.Packets() {
		appLayer := packet.ApplicationLayer()
		if appLayer != nil {
			payload := appLayer.Payload()
			if len(payload) == UDPSize {
				f.Write(payload)
			} else if len(payload) == HRTPSize {
				offset := HRTPSize - UDPSize
				f.Write(payload[offset:HRTPSize])
			}
		}
	}
}

func getOpstream(cfg OpStreamSettings) (*packetHandlerContext, error) {
	if cfg.PacketBufSize < 1 {
		return nil, fmt.Errorf("invalid packet buffer size")
	}

	var pcapHandle *pcap.Handle
	var err error
	if len(cfg.PcapFile) > 0 {
		pcapHandle, err = pcap.OpenOffline(cfg.PcapFile)
		if err != nil {
			return nil, fmt.Errorf("error opening pcap file: %v", err)
		}
	} else if len(cfg.NetworkInterface) > 0 {
		pcapHandle, err = pcap.OpenLive(cfg.NetworkInterface, 32*1024*1024, false, pcap.BlockForever)
		if err != nil {
			return nil, fmt.Errorf("error listening to network interface: %v", err)
		}
	} else {
		return nil, fmt.Errorf("must specify either a pcap file or network interface to record from")
	}

	if len(cfg.Expression) > 0 {
		err = pcapHandle.SetBPFFilter(cfg.Expression)
		if err != nil {
			return nil, fmt.Errorf("error setting packet filter expression: %v", err)
		}
	}

	h := NewPacketHandler(pcapHandle)
	h.Verbose = userInfoLogger.isInVerbosity(DebugLow)

	toolDebugLogger.Logvf(Info, "Created packet buffer size %d", cfg.PacketBufSize)
	m := NewMongoOpStream(cfg.PacketBufSize)
	return &packetHandlerContext{h, m, pcapHandle}, nil
}

func openFile(pcapFile string) *pcap.Handle {
	handle, err := pcap.OpenOffline(pcapFile)
	if err != nil {
		log.Fatal("Open file", pcapFile, "error:", err)
	}
	return handle
}

func main() {
	defer util.Run()()
	var handle *pcap.Handle
	var err error

	// Set up pcap packet capture
	if *fname != "" {
		log.Printf("Reading from pcap dump %q", *fname)
		handle, err = pcap.OpenOffline(*fname)
	} else {
		log.Fatalln("Error: pcap file name is required!")
		// log.Printf("Starting capture on interface %q", *iface)
		// handle, err = pcap.OpenLive(*iface, int32(*snaplen), true, pcap.BlockForever)
	}
	if err != nil {
		log.Fatal(err)
	}

	if err := handle.SetBPFFilter(*filter); err != nil {
		log.Fatal(err)
	}

	// Set up assembly
	streamFactory := &httpStreamFactory{}
	streamPool := tcpassembly.NewStreamPool(streamFactory)
	assembler := tcpassembly.NewAssembler(streamPool)

	log.Println("reading in packets")
	// Read in packets, pass to assembler.
	packetSource := gopacket.NewPacketSource(handle, handle.LinkType())
	packets := packetSource.Packets()
	ticker := time.Tick(time.Minute)
	for {
		select {
		case packet := <-packets:
			// A nil packet indicates the end of a pcap file.
			if packet == nil {
				return
			}
			if *logAllPackets {
				log.Println("\npacket:")
				// log.Println(packet)
			}
			if packet.NetworkLayer() == nil || packet.TransportLayer() == nil || packet.TransportLayer().LayerType() != layers.LayerTypeTCP {
				log.Println("Unusable packet")
				continue
			}
			tcp := packet.TransportLayer().(*layers.TCP)
			log.Printf("\n.......................................................\n")
			log.Printf("packet:\n")
			log.Printf("packet.Metadata().Timestamp=%T=%v=%v:\n%#v\n", packet.Metadata().Timestamp, packet.Metadata().Timestamp, packet.Metadata().Timestamp.UTC(), packet.Metadata().Timestamp)
			assembler.AssembleWithTimestamp(packet.NetworkLayer().NetworkFlow(), tcp, packet.Metadata().Timestamp)

		case <-ticker:
			// Every minute, flush connections that haven't seen activity in the past 2 minutes.
			assembler.FlushOlderThan(time.Now().Add(time.Minute * -2))
		}
	}
}