ing

discovery/discoverer.go

@@ -142,6 +142,7 @@ LOOP:
 			}
 			req.(*ofDiscoveryRequest).release()
 
+			log.Print("Discovery Session complete")
 		case <-d.stopChan:
 			return
 		}

discovery/protocol/arp/arp.go

@@ -25,15 +25,11 @@ func Scan(discoverySession session.DiscoverySession) error {
 
 	zone := discoverySession.Zone()
 
-	ps, err := pcap.RetainScanner(zone)
+	ps := discoverySession.PCapScanner()
-	if nil != err {
+	if nil == ps {
-		return fmt.Errorf("Cannot retain pcap instance %v", err)
+		return fmt.Errorf("Cannot retain pcap instance")
 	}
 
-	defer func() {
-		pcap.ReleaseScanner(zone)
-	}()
-
 	arpChan := ps.OpenARP()
 	defer func() {
 		ps.CloseARP(arpChan)
@@ -57,16 +53,13 @@ func Scan(discoverySession session.DiscoverySession) error {
 				delay.Store(true)
 				if h := handlePacketARP(zone, targetHosts, hosts, packet); nil != h {
 					if h != nil {
-						// log.Print("Host ", h)
 						discoverySession.AddHost(h)
 					}
-
-					// resultChan <- h
 				}
 			case <-ticker.C:
 				if false == delay.Load().(bool) {
 					ticker.Stop()
-					timerStopped <- struct{}{}
+					close(timerStopped)
 					return
 				}
 				delay.Store(false)

discovery/protocol/icmp/icmp.go

@@ -4,21 +4,10 @@ import (
 	"git.loafle.net/overflow_scanner/probe/discovery/protocol/icmp/privileged"
 	"git.loafle.net/overflow_scanner/probe/discovery/protocol/icmp/unprivileged"
 	"git.loafle.net/overflow_scanner/probe/discovery/session"
-	"git.loafle.net/overflow_scanner/probe/internal/pcap"
 )
 
 func Scan(discoverySession session.DiscoverySession) error {
-	zone := discoverySession.Zone()
+	if nil != discoverySession.PCapScanner() {
-
-	var _privileged bool
-
-	_, err := pcap.RetainScanner(zone)
-	if nil == err {
-		pcap.ReleaseScanner(zone)
-		_privileged = true
-	}
-
-	if _privileged {
 		return privileged.Scan(discoverySession)
 	}
 

discovery/protocol/icmp/privileged/icmpv4.go

@@ -27,15 +27,11 @@ func scanV4(discoverySession session.DiscoverySession) error {
 
 	zone := discoverySession.Zone()
 
-	ps, err := pcap.RetainScanner(zone)
+	ps := discoverySession.PCapScanner()
-	if nil != err {
+	if nil == ps {
-		return fmt.Errorf("Cannot retain pcap instance %v", err)
+		return fmt.Errorf("Cannot retain pcap instance")
 	}
 
-	defer func() {
-		pcap.ReleaseScanner(zone)
-	}()
-
 	icmpChan := ps.OpenICMP4()
 	defer func() {
 		ps.CloseICMP4(icmpChan)

discovery/protocol/icmp/privileged/icmpv6.go

@@ -27,15 +27,11 @@ func scanV6(discoverySession session.DiscoverySession) error {
 
 	zone := discoverySession.Zone()
 
-	ps, err := pcap.RetainScanner(zone)
+	ps := discoverySession.PCapScanner()
-	if nil != err {
+	if nil == ps {
-		return fmt.Errorf("Cannot retain pcap instance %v", err)
+		return fmt.Errorf("Cannot retain pcap instance")
 	}
 
-	defer func() {
-		pcap.ReleaseScanner(zone)
-	}()
-
 	icmpChan := ps.OpenICMP6()
 	defer func() {
 		ps.CloseICMP6(icmpChan)

discovery/protocol/tcp/syn/synv4.go

@@ -19,13 +19,10 @@ import (
 )
 
 func scanV4(discoverySession session.DiscoverySession, targetHost *omd.Host) error {
-	ps, err := pcap.RetainScanner(targetHost.Zone)
+	ps := discoverySession.PCapScanner()
-	if nil != err {
+	if nil == ps {
-		return fmt.Errorf("Discovery: Cannot retain pcap instance %v", err)
+		return fmt.Errorf("Cannot retain pcap instance")
 	}
-	defer func() {
-		go pcap.ReleaseScanner(targetHost.Zone)
-	}()
 
 	tcpChan := ps.OpenTCP(targetHost.Address)
 	defer func() {
@@ -33,6 +30,9 @@ func scanV4(discoverySession session.DiscoverySession, targetHost *omd.Host) err
 	}()
 
 	timerStopped := make(chan struct{})
+	stopChan := make(chan struct{})
+	defer close(stopChan)
+
 	go func() {
 		ports := make(map[int]*omd.Port)
 
@@ -47,9 +47,13 @@ func scanV4(discoverySession session.DiscoverySession, targetHost *omd.Host) err
 					return
 				}
 				delay.Store(true)
+				// go func(packet *layers.TCP) {
 				if p := handlePacketTCP4(discoverySession, targetHost, ports, packet); nil != p {
 					discoverySession.AddPort(p)
+					log.Print(p)
 				}
+
+				// }(packet)
 			case <-ticker.C:
 				if false == delay.Load().(bool) {
 					ticker.Stop()
@@ -61,7 +65,7 @@ func scanV4(discoverySession session.DiscoverySession, targetHost *omd.Host) err
 		}
 	}()
 
-	if err := sendTCP4(discoverySession, ps, targetHost); nil != err {
+	if err := sendTCP4(discoverySession, ps, targetHost, stopChan); nil != err {
 		log.Printf("sendTCP %v", err)
 		return nil
 	}
@@ -74,7 +78,7 @@ func scanV4(discoverySession session.DiscoverySession, targetHost *omd.Host) err
 	}
 }
 
-func sendTCP4(discoverySession session.DiscoverySession, ps pcap.PCapScanner, host *omd.Host) error {
+func sendTCP4(discoverySession session.DiscoverySession, ps pcap.PCapScanner, host *omd.Host, stopChan chan struct{}) error {
 	dp := discoverySession.DiscoverPort()
 
 	tcpPacket, err := makePacketPortTCP4(host)
@@ -109,6 +113,8 @@ Loop:
 
 		select {
 		case <-timer.C:
+		case <-stopChan:
+			return nil
 		}
 	}
 

discovery/protocol/tcp/syn/synv4_test.go

@@ -8,7 +8,6 @@ import (
 	"git.loafle.net/overflow_scanner/probe/__test"
 	"git.loafle.net/overflow_scanner/probe/discovery/session"
 	"git.loafle.net/overflow_scanner/probe/discovery/types"
-	"git.loafle.net/overflow_scanner/probe/internal/pcap"
 	"github.com/google/gopacket/layers"
 )
 
@@ -65,27 +64,27 @@ func Test_scanV4(t *testing.T) {
 	}
 }
 
-func Test_sendTCP4(t *testing.T) {
+// func Test_sendTCP4(t *testing.T) {
-	type args struct {
+// 	type args struct {
-		discoverySession session.DiscoverySession
+// 		discoverySession session.DiscoverySession
-		ps               pcap.PCapScanner
+// 		ps               pcap.PCapScanner
-		host             *omd.Host
+// 		host             *omd.Host
-	}
+// 	}
-	tests := []struct {
+// 	tests := []struct {
-		name    string
+// 		name    string
-		args    args
+// 		args    args
-		wantErr bool
+// 		wantErr bool
-	}{
+// 	}{
-		// TODO: Add test cases.
+// 		// TODO: Add test cases.
-	}
+// 	}
-	for _, tt := range tests {
+// 	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
+// 		t.Run(tt.name, func(t *testing.T) {
-			if err := sendTCP4(tt.args.discoverySession, tt.args.ps, tt.args.host); (err != nil) != tt.wantErr {
+// 			if err := sendTCP4(tt.args.discoverySession, tt.args.ps, tt.args.host); (err != nil) != tt.wantErr {
-				t.Errorf("sendTCP4() error = %v, wantErr %v", err, tt.wantErr)
+// 				t.Errorf("sendTCP4() error = %v, wantErr %v", err, tt.wantErr)
-			}
+// 			}
-		})
+// 		})
-	}
+// 	}
-}
+// }
 
 func Test_handlePacketTCP4(t *testing.T) {
 	type args struct {

discovery/protocol/udp/matcher/matcher4.go

@@ -12,6 +12,7 @@ import (
 	omd "git.loafle.net/overflow/model/discovery"
 	omm "git.loafle.net/overflow/model/meta"
 	omu "git.loafle.net/overflow/model/util"
+	osm "git.loafle.net/overflow/service_matcher-go"
 	"git.loafle.net/overflow_scanner/probe/discovery/session"
 	"git.loafle.net/overflow_scanner/probe/internal/matcher"
 	"git.loafle.net/overflow_scanner/probe/internal/pcap"
@@ -20,13 +21,10 @@ import (
 )
 
 func scanV4(discoverySession session.DiscoverySession, targetHost *omd.Host) error {
-	ps, err := pcap.RetainScanner(targetHost.Zone)
+	ps := discoverySession.PCapScanner()
-	if nil != err {
+	if nil == ps {
-		return fmt.Errorf("Discovery: Cannot retain pcap instance %v", err)
+		return fmt.Errorf("Cannot retain pcap instance")
 	}
-	defer func() {
-		go pcap.ReleaseScanner(targetHost.Zone)
-	}()
 
 	udpChan := ps.OpenUDP(targetHost.Address)
 	defer func() {
@@ -108,9 +106,11 @@ func sendUDP4(discoverySession session.DiscoverySession, ps pcap.PCapScanner, ho
 				continue INNER_LOOP
 			}
 
+			matchCtx := osm.NewMatchCtx(host.Address, portNumber)
+
 			addr := &net.UDPAddr{IP: ip.To4(), Port: portNumber}
-			for i := 0; i < _matcher.PacketCount(); i++ {
+			for i := 0; i < _matcher.PacketCount(matchCtx); i++ {
-				p := _matcher.Packet(i)
+				p := _matcher.Packet(matchCtx, i)
 				if _, err := conn.WriteToUDP(p.Buffer, addr); err != nil {
 					log.Print("UDP write error", err)
 				}

discovery/protocol/upnp/upnp.go

@@ -28,8 +28,6 @@ LOOP:
 			continue LOOP
 		}
 
-		// log.Print(rd)
-
 		discoverySession.AddHost(&omd.Host{
 			MetaIPType: discoverySession.Zone().MetaIPType,
 			Name:       rd.FriendlyName,

discovery/session/discovery-session.go

@@ -10,6 +10,7 @@ import (
 	omd "git.loafle.net/overflow/model/discovery"
 	ounc "git.loafle.net/overflow/util-go/net/cidr"
 	"git.loafle.net/overflow_scanner/probe/discovery/types"
+	"git.loafle.net/overflow_scanner/probe/internal/pcap"
 )
 
 type DiscoverySession interface {
@@ -17,6 +18,8 @@ type DiscoverySession interface {
 
 	DiscoveryRequest() types.DiscoveryRequest
 
+	PCapScanner() pcap.PCapScanner
+
 	Zone() *omd.Zone
 	Host() *omd.Host
 	Port() *omd.Port
@@ -47,6 +50,7 @@ type DiscoverySession interface {
 
 type ofDiscoverySession struct {
 	discoveryRequest types.DiscoveryRequest
+	pCapScanner      pcap.PCapScanner
 
 	zone *omd.Zone
 	host *omd.Host
@@ -79,6 +83,7 @@ func (ds *ofDiscoverySession) init(request types.DiscoveryRequest) {
 	ds.discoverHost = nil
 	ds.discoverPort = nil
 	ds.discoverService = nil
+	ds.pCapScanner = nil
 
 	ds.hosts = make(map[string]*omd.Host)
 	ds.includeMachosts = make(map[string]*omd.Host)
@@ -168,9 +173,18 @@ func (ds *ofDiscoverySession) InitWithRequest(request types.DiscoveryRequest) er
 		ds.setDiscoverService(discoverService)
 	}
 
+	_pCapScanner := pcap.NewPCapScanner(ds.zone)
+	if err := _pCapScanner.Start(); nil == err {
+		ds.pCapScanner = _pCapScanner
+	}
+
 	return nil
 }
 
+func (ds *ofDiscoverySession) PCapScanner() pcap.PCapScanner {
+	return ds.pCapScanner
+}
+
 func (ds *ofDiscoverySession) SetDiscoveryDelegator(discoveryDelegator chan<- interface{}) {
 	ds.discoveryDelegator = discoveryDelegator
 }
@@ -568,20 +582,26 @@ func RetainDiscoverySession() *ofDiscoverySession {
 func ReleaseDiscoverySession(ds *ofDiscoverySession) {
 	close(ds.stopChan)
 
-	// timer := time.NewTimer(time.Microsecond * 500)
+	if nil != ds.pCapScanner {
-
+		ds.pCapScanner.Stop()
-	// select {
+	}
-	// case <-timer.C:
-	// }
 
+	ds.pCapScanner = nil
 	ds.discoveryRequest = nil
 	ds.zone = nil
 	ds.host = nil
 	ds.port = nil
+
+	ds.discoveryConfig = nil
+
 	ds.discoverHost = nil
 	ds.discoverPort = nil
 	ds.discoverService = nil
 
+	ds.targetHosts = nil
+
+	ds.discoveryDelegator = nil
+
 	ds.includeMachosts = nil
 	ds.hosts = nil
 	ds.ports = nil

discovery/target/host/host.go

@@ -6,7 +6,6 @@ import (
 	"git.loafle.net/overflow_scanner/probe/discovery/protocol/arp"
 	"git.loafle.net/overflow_scanner/probe/discovery/protocol/icmp"
 	"git.loafle.net/overflow_scanner/probe/discovery/session"
-	"git.loafle.net/overflow_scanner/probe/internal/pcap"
 )
 
 func Scan(discoverySession session.DiscoverySession) error {
@@ -15,17 +14,7 @@ func Scan(discoverySession session.DiscoverySession) error {
 		return nil
 	}
 
-	zone := discoverySession.Zone()
+	if nil != discoverySession.PCapScanner() {
-
-	var privileged bool
-
-	_, err := pcap.RetainScanner(zone)
-	if nil == err {
-		pcap.ReleaseScanner(zone)
-		privileged = true
-	}
-
-	if privileged {
 		return privilegedScan(discoverySession)
 	}
 

discovery/target/port/port.go

@@ -7,7 +7,6 @@ import (
 	"git.loafle.net/overflow_scanner/probe/discovery/protocol/tcp/connection"
 	"git.loafle.net/overflow_scanner/probe/discovery/protocol/tcp/syn"
 	"git.loafle.net/overflow_scanner/probe/discovery/session"
-	"git.loafle.net/overflow_scanner/probe/internal/pcap"
 )
 
 func Scan(discoverySession session.DiscoverySession, targetHost *omd.Host) error {
@@ -15,17 +14,7 @@ func Scan(discoverySession session.DiscoverySession, targetHost *omd.Host) error
 		return nil
 	}
 
-	zone := discoverySession.Zone()
+	if nil != discoverySession.PCapScanner() {
-
-	var privileged bool
-
-	_, err := pcap.RetainScanner(zone)
-	if nil == err {
-		pcap.ReleaseScanner(zone)
-		privileged = true
-	}
-
-	if privileged {
 		return privilegedScan(discoverySession, targetHost)
 	}
 

discovery/target/service/service-tcp.go

@@ -13,6 +13,10 @@ import (
 	"git.loafle.net/overflow_scanner/probe/internal/matcher"
 )
 
+const (
+	deadline = time.Millisecond * 500
+)
+
 func scanTCP(discoverySession session.DiscoverySession, targetPort *omd.Port) error {
 	hostAddress := targetPort.Host.Address
 	portNumber, err := ouej.NumberToInt(targetPort.PortNumber)
@@ -38,7 +42,7 @@ LOOP:
 			continue LOOP
 		}
 
-		if err := conn.SetReadDeadline(time.Now().Add(1 * time.Second)); nil != err {
+		if err := conn.SetReadDeadline(time.Now().Add(deadline)); nil != err {
 			continue LOOP
 		}
 		n, err := conn.Read(buf)
@@ -113,7 +117,7 @@ LOOP:
 		for j := 0; j < packetCount; j++ {
 			_packet := _matcher.Packet(matchCtx, j)
 
-			if err := conn.SetWriteDeadline(time.Now().Add(1 * time.Second)); nil != err {
+			if err := conn.SetWriteDeadline(time.Now().Add(deadline)); nil != err {
 				return nil
 			}
 			_, err := conn.Write(_packet.Buffer)
@@ -121,7 +125,7 @@ LOOP:
 				return nil
 			}
 
-			if err := conn.SetReadDeadline(time.Now().Add(1 * time.Second)); nil != err {
+			if err := conn.SetReadDeadline(time.Now().Add(deadline)); nil != err {
 				return nil
 			}
 			n, err := conn.Read(buf)
@@ -177,7 +181,7 @@ LOOP:
 		for j := 0; j < packetCount; j++ {
 			_packet := _matcher.Packet(matchCtx, j)
 
-			if err := conn.SetWriteDeadline(time.Now().Add(1 * time.Second)); nil != err {
+			if err := conn.SetWriteDeadline(time.Now().Add(deadline)); nil != err {
 				break INNER_LOOP
 			}
 			_, err := conn.Write(_packet.Buffer)
@@ -185,7 +189,7 @@ LOOP:
 				break INNER_LOOP
 			}
 
-			if err := conn.SetReadDeadline(time.Now().Add(1 * time.Second)); nil != err {
+			if err := conn.SetReadDeadline(time.Now().Add(deadline)); nil != err {
 				break INNER_LOOP
 			}
 			n, err := conn.Read(buf)

internal/pcap/packet.go

@@ -110,20 +110,27 @@ func handlePacketTCP(ps *pCapScan, packet gopacket.Packet) {
 	}
 
 	ip := ipLayer.(*layers.IPv4).SrcIP.String()
-
-	ps.tcpListenerChanMtx.RLock()
-	defer ps.tcpListenerChanMtx.RUnlock()
-
-	chs, ok := ps.tcpListenerChans[ip]
-	if ok {
-
 	layer := packet.Layer(layers.LayerTypeTCP)
 	tcp, _ := layer.(*layers.TCP)
 
+	ps.tcpListenerChanMtx.RLock()
+	defer func() {
+		ps.tcpListenerChanMtx.RUnlock()
+	}()
+
+	chs, ok := ps.tcpListenerChans[ip]
+	if ok {
+		// for _, ch := range chs {
+		// 	ch <- tcp
+		// }
 		for _, ch := range chs {
-			ch <- tcp
+			select {
+			case ch <- tcp:
+			default:
 			}
 		}
+
+	}
 }
 
 func handlePacketUDP(ps *pCapScan, packet gopacket.Packet) {

internal/pcap/pcap.go

@@ -1,33 +1,37 @@
 package pcap
 
 import (
+	"log"
 	"sync"
 	"time"
 
 	omd "git.loafle.net/overflow/model/discovery"
 )
 
-var mtx sync.Mutex
+var instances sync.Map
-var instances map[string]PCapScanner
+
+// var instances map[string]PCapScanner
 
 func init() {
-	instances = make(map[string]PCapScanner, 0)
+	// instances = make(map[string]PCapScanner, 0)
 }
 
 func RetainScanner(zone *omd.Zone) (PCapScanner, error) {
-	mtx.Lock()
-	defer mtx.Unlock()
-
 	var ps PCapScanner
-	var ok bool
+	// if ps, ok = instances[zone.Network]; !ok {
-	if ps, ok = instances[zone.Network]; !ok {
+
-		ps = newPCapScanner(zone)
+	_ps, ok := instances.Load(zone.Network)
-		if err := ps.start(); nil != err {
+	if !ok {
+		ps = NewPCapScanner(zone)
+		if err := ps.Start(); nil != err {
 			return nil, err
 		}
-		instances[zone.Network] = ps
+		instances.Store(zone.Network, ps)
+	} else {
+		ps = _ps.(PCapScanner)
 	}
 	ps.retain()
+	log.Print("Pcap retain")
 
 	return ps, nil
 }
@@ -35,26 +39,28 @@ func RetainScanner(zone *omd.Zone) (PCapScanner, error) {
 func ReleaseScanner(zone *omd.Zone) {
 
 	go func() {
-		time.Sleep(2 * time.Second)
+		time.Sleep(1 * time.Second)
 
-		mtx.Lock()
+		if _ps, ok := instances.Load(zone.Network); ok {
-		defer mtx.Unlock()
+			ps := _ps.(PCapScanner)
-
+			log.Print("Pcap release")
-		if ps, ok := instances[zone.Network]; ok {
 			if ps.release() {
-				ps.stop()
+				ps.Stop()
-				delete(instances, zone.Network)
+				instances.Delete(zone.Network)
 			}
 		}
 	}()
 }
 
 func ReleaseScannerAll() {
-	mtx.Lock()
+	instances.Range(func(k, v interface{}) bool {
-	defer mtx.Unlock()
+		ps := v.(PCapScanner)
-
+		if ps.release() {
-	for k, ps := range instances {
+			ps.Stop()
-		ps.stop()
+			instances.Delete(k)
-		delete(instances, k)
+			return false
 		}
+
+		return true
+	})
 }

internal/pcap/pcap_scan.go

@@ -9,9 +9,10 @@ import (
 	"github.com/google/gopacket"
 	"github.com/google/gopacket/layers"
 	"github.com/google/gopacket/pcap"
+	deadlock "github.com/sasha-s/go-deadlock"
 )
 
-func newPCapScanner(zone *omd.Zone) PCapScanner {
+func NewPCapScanner(zone *omd.Zone) PCapScanner {
 	ps := &pCapScan{
 		zone: zone,
 	}
@@ -37,8 +38,8 @@ type PCapScanner interface {
 
 	WritePacketData(data []byte) (err error)
 
-	start() error
+	Start() error
-	stop()
+	Stop()
 
 	retain()
 	release() bool
@@ -48,19 +49,24 @@ type pCapScan struct {
 	pCapHandle *pcap.Handle
 	zone       *omd.Zone
 
-	arpListenerChanMtx sync.RWMutex
+	// arpListenerChanMtx sync.RWMutex
+	arpListenerChanMtx deadlock.RWMutex
 	arpListenerChans   []chan *layers.ARP
 
-	icmp4ListenerChanMtx sync.RWMutex
+	// icmp4ListenerChanMtx sync.RWMutex
+	icmp4ListenerChanMtx deadlock.RWMutex
 	icmp4ListenerChans   []chan gopacket.Packet
 
-	icmp6ListenerChanMtx sync.RWMutex
+	// icmp6ListenerChanMtx sync.RWMutex
+	icmp6ListenerChanMtx deadlock.RWMutex
 	icmp6ListenerChans   []chan gopacket.Packet
 
-	tcpListenerChanMtx sync.RWMutex
+	// tcpListenerChanMtx sync.RWMutex
+	tcpListenerChanMtx deadlock.RWMutex
 	tcpListenerChans   map[string][]chan *layers.TCP
 
-	udpListenerChanMtx sync.RWMutex
+	// udpListenerChanMtx sync.RWMutex
+	udpListenerChanMtx deadlock.RWMutex
 	udpListenerChans   map[string][]chan gopacket.Packet
 
 	refCount int
@@ -68,7 +74,7 @@ type pCapScan struct {
 	stopWg   sync.WaitGroup
 }
 
-func (ps *pCapScan) start() error {
+func (ps *pCapScan) Start() error {
 	if ps.stopChan != nil {
 		return fmt.Errorf("PCapScanner: already running. Stop it before starting it again")
 	}
@@ -81,8 +87,8 @@ func (ps *pCapScan) start() error {
 	}
 	// set filter
 	// todo add tcp, udp filter
-	//if err = h.SetBPFFilter("arp and src net " + ps.zone.Network + " or (((tcp[tcpflags] & (tcp-syn|tcp-ack) != 0) or (tcp[tcpflags] & (tcp-rst) != 0)) and port 60000) or udp "); nil != err {
+	if err = h.SetBPFFilter("arp or icmp or icmp6 and src net " + ps.zone.Network + " or (((tcp[tcpflags] & (tcp-syn|tcp-ack) != 0) or (tcp[tcpflags] & (tcp-rst) != 0)) and port 60000) or udp "); nil != err {
-	if err = h.SetBPFFilter("arp or icmp or icmp6 or tcp or udp"); nil != err {
+		// if err = h.SetBPFFilter("arp or icmp or icmp6 or tcp or udp"); nil != err {
 		h.Close()
 		return err
 	}
@@ -102,7 +108,7 @@ func (ps *pCapScan) start() error {
 	return nil
 }
 
-func (ps *pCapScan) stop() {
+func (ps *pCapScan) Stop() {
 	if ps.stopChan == nil {
 		panic("PCapScanner: must be started before stopping it")
 	}
@@ -115,7 +121,7 @@ func (ps *pCapScan) OpenARP() chan *layers.ARP {
 	ps.arpListenerChanMtx.Lock()
 	defer ps.arpListenerChanMtx.Unlock()
 
-	c := make(chan *layers.ARP, 0)
+	c := make(chan *layers.ARP, 128)
 	ps.arpListenerChans = append(ps.arpListenerChans, c)
 	return c
 }
@@ -137,7 +143,7 @@ func (ps *pCapScan) OpenICMP4() chan gopacket.Packet {
 	ps.icmp4ListenerChanMtx.Lock()
 	defer ps.icmp4ListenerChanMtx.Unlock()
 
-	c := make(chan gopacket.Packet, 0)
+	c := make(chan gopacket.Packet, 128)
 	ps.icmp4ListenerChans = append(ps.icmp4ListenerChans, c)
 	return c
 }
@@ -159,7 +165,7 @@ func (ps *pCapScan) OpenICMP6() chan gopacket.Packet {
 	ps.icmp6ListenerChanMtx.Lock()
 	defer ps.icmp6ListenerChanMtx.Unlock()
 
-	c := make(chan gopacket.Packet, 0)
+	c := make(chan gopacket.Packet, 128)
 	ps.icmp6ListenerChans = append(ps.icmp6ListenerChans, c)
 	return c
 }
@@ -185,7 +191,7 @@ func (ps *pCapScan) OpenTCP(ip string) chan *layers.TCP {
 		ps.tcpListenerChans[ip] = make([]chan *layers.TCP, 0)
 	}
 
-	ch := make(chan *layers.TCP, 0)
+	ch := make(chan *layers.TCP, 1024)
 	ps.tcpListenerChans[ip] = append(ps.tcpListenerChans[ip], ch)
 
 	return ch
@@ -218,7 +224,7 @@ func (ps *pCapScan) OpenUDP(ip string) chan gopacket.Packet {
 		ps.udpListenerChans[ip] = make([]chan gopacket.Packet, 0)
 	}
 
-	ch := make(chan gopacket.Packet, 0)
+	ch := make(chan gopacket.Packet, 256)
 	ps.udpListenerChans[ip] = append(ps.udpListenerChans[ip], ch)
 
 	return ch
@@ -313,7 +319,7 @@ func handleReceive(ps *pCapScan) {
 	for {
 		select {
 		case packet := <-inPacket:
-			handlePacket(ps, packet)
+			go handlePacket(ps, packet)
 		case <-ps.stopChan:
 			ps.destroy()
 			return