misc: small fix or general refactoring i did not bother commenting

modules/syn_scan/banner_grabbing.go

@@ -2,15 +2,17 @@ package syn_scan
 
 import (
 	"fmt"
-	"github.com/bettercap/bettercap/network"
+	"time"
 
 	"github.com/evilsocket/islazy/async"
 )
 
+const bannerGrabTimeout = time.Duration(5) * time.Second
+
 type bannerGrabberFn func(mod *SynScanner, ip string, port int) string
 
 type grabberJob struct {
-	Host *network.Endpoint
+	IP   string
 	Port *OpenPort
 }
 
@@ -20,7 +22,7 @@ func (mod *SynScanner) bannerGrabber(arg async.Job) {
 		return
 	}
 
-	ip := job.Host.IpAddress
+	ip := job.IP
 	port := job.Port.Port
 	sport := fmt.Sprintf("%d", port)
 

modules/syn_scan/http_grabber.go

@@ -7,7 +7,6 @@ import (
 	"golang.org/x/net/html"
 	"net/http"
 	"strings"
-	"time"
 )
 
 func isTitleElement(n *html.Node) bool {
@@ -30,9 +29,8 @@ func searchForTitle(n *html.Node) string {
 
 func httpGrabber(mod *SynScanner, ip string, port int) string {
 	schema := "http"
-	timeout := time.Duration(10 * time.Second)
 	client := &http.Client{
-		Timeout: timeout,
+		Timeout: bannerGrabTimeout,
 		CheckRedirect: func(req *http.Request, via []*http.Request) error {
 			return nil
 		},
@@ -42,7 +40,7 @@ func httpGrabber(mod *SynScanner, ip string, port int) string {
 	if strings.Contains(sport, "443") {
 		schema = "https"
 		client = &http.Client{
-			Timeout: timeout,
+			Timeout: bannerGrabTimeout,
 			Transport: &http.Transport{
 				TLSClientConfig: &tls.Config{
 					InsecureSkipVerify: true,

modules/syn_scan/syn_scan.go

@@ -50,7 +50,7 @@ func NewSynScanner(s *session.Session) *SynScanner {
 	}
 
 	mod.scanQueue = async.NewQueue(0, mod.scanWorker)
-	mod.bannerQueue = async.NewQueue(4, mod.bannerGrabber)
+	mod.bannerQueue = async.NewQueue(0, mod.bannerGrabber)
 
 	mod.State.Store("scanning", &mod.addresses)
 	mod.State.Store("progress", 0.0)
@@ -120,6 +120,7 @@ func (mod *SynScanner) Configure() (err error) {
 		} else if err = mod.handle.SetBPFFilter(fmt.Sprintf("tcp dst port %d", synSourcePort)); err != nil {
 			return err
 		}
+		mod.packets = gopacket.NewPacketSource(mod.handle, mod.handle.LinkType()).Packets()
 	}
 	return nil
 }
@@ -155,10 +156,6 @@ func (mod *SynScanner) Stop() error {
 	return mod.SetRunning(false, func() {
 		mod.packets <- nil
 		mod.waitGroup.Wait()
-		mod.showProgress()
-		mod.addresses = []net.IP{}
-		mod.State.Store("progress", 0.0)
-		mod.State.Store("scanning", &mod.addresses)
 	})
 }
 
@@ -203,6 +200,7 @@ func (mod *SynScanner) synScan() error {
 		defer mod.waitGroup.Done()
 
 		defer mod.SetRunning(false, func() {
+			mod.showProgress()
 			mod.addresses = []net.IP{}
 			mod.State.Store("progress", 0.0)
 			mod.State.Store("scanning", &mod.addresses)
@@ -233,8 +231,6 @@ func (mod *SynScanner) synScan() error {
 			mod.waitGroup.Add(1)
 			defer mod.waitGroup.Done()
 
-			src := gopacket.NewPacketSource(mod.handle, mod.handle.LinkType())
-			mod.packets = src.Packets()
 			for packet := range mod.packets {
 				if !mod.Running() {
 					break

modules/syn_scan/syn_scan_reader.go

@@ -46,6 +46,12 @@ func (mod *SynScanner) onPacket(pkt gopacket.Packet) {
 		from := ip.SrcIP.String()
 		port := int(tcp.SrcPort)
 
+		openPort := &OpenPort{
+			Proto:   "tcp",
+			Port:    port,
+			Service: network.GetServiceByPort(port, "tcp"),
+		}
+
 		var host *network.Endpoint
 		if ip.SrcIP.Equal(mod.Session.Interface.IP) {
 			host = mod.Session.Interface
@@ -58,20 +64,13 @@ func (mod *SynScanner) onPacket(pkt gopacket.Packet) {
 		if host != nil {
 			ports := host.Meta.GetOr("ports", map[int]*OpenPort{}).(map[int]*OpenPort)
 			if _, found := ports[port]; !found {
-				openPort := &OpenPort{
-					Proto:   "tcp",
-					Port:    port,
-					Service: network.GetServiceByPort(port, "tcp"),
-				}
-
 				ports[port] = openPort
-
-				mod.bannerQueue.Add(async.Job(grabberJob{host, openPort}))
 			}
-
 			host.Meta.Set("ports", ports)
 		}
 
+		mod.bannerQueue.Add(async.Job(grabberJob{from, openPort}))
+
 		NewSynScanEvent(from, host, port).Push()
 	}
 }

modules/syn_scan/tcp_grabber.go

@@ -19,10 +19,16 @@ func cleanBanner(banner string) string {
 }
 
 func tcpGrabber(mod *SynScanner, ip string, port int) string {
-	if conn, err := net.Dial("tcp", fmt.Sprintf("%s:%d", ip, port)); err == nil {
+	dialer := net.Dialer{
+		Timeout: bannerGrabTimeout,
+	}
+
+	if conn, err := dialer.Dial("tcp", fmt.Sprintf("%s:%d", ip, port)); err == nil {
 		defer conn.Close()
 		msg, _ := bufio.NewReader(conn).ReadString('\n')
 		return cleanBanner(strings.Trim(msg, "\r\n\t "))
+	} else {
+		mod.Debug("%s:%d : %v", ip, port, err)
 	}
 	return ""
 }