refact: session/modules -> modules

modules/net_recon.go

@@ -0,0 +1,160 @@
+package modules
+
+import (
+	"fmt"
+	"github.com/evilsocket/bettercap-ng/net"
+	"github.com/evilsocket/bettercap-ng/session"
+	"time"
+)
+
+type Discovery struct {
+	session.SessionModule
+
+	refresh int
+	before  net.ArpTable
+	current net.ArpTable
+	quit    chan bool
+}
+
+func NewDiscovery(s *session.Session) *Discovery {
+	d := &Discovery{
+		SessionModule: session.NewSessionModule("net.recon", s),
+
+		refresh: 1,
+		before:  nil,
+		current: nil,
+		quit:    make(chan bool),
+	}
+
+	d.AddHandler(session.NewModuleHandler("net.recon on", "",
+		"Start network hosts discovery.",
+		func(args []string) error {
+			return d.Start()
+		}))
+
+	d.AddHandler(session.NewModuleHandler("net.recon off", "",
+		"Stop network hosts discovery.",
+		func(args []string) error {
+			return d.Stop()
+		}))
+
+	d.AddHandler(session.NewModuleHandler("net.show", "",
+		"Show current hosts list.",
+		func(args []string) error {
+			return d.Show()
+		}))
+
+	return d
+}
+
+func (d Discovery) Name() string {
+	return "Network Recon"
+}
+
+func (d Discovery) Description() string {
+	return "Read periodically the ARP cache in order to monitor for new hosts on the network."
+}
+
+func (d Discovery) Author() string {
+	return "Simone Margaritelli <evilsocket@protonmail.com>"
+}
+
+func (d Discovery) OnSessionEnded(s *session.Session) {
+	if d.Running() {
+		d.Stop()
+	}
+}
+
+func (d *Discovery) checkShared(new net.ArpTable) {
+	n_gw_shared := 0
+	for ip, mac := range new {
+		if ip != d.Session.Gateway.IpAddress && mac == d.Session.Gateway.HwAddress {
+			n_gw_shared++
+		}
+	}
+
+	if n_gw_shared > 0 {
+		a := ""
+		b := ""
+		if n_gw_shared == 1 {
+			a = ""
+			b = "s"
+		} else {
+			a = "s"
+			b = ""
+		}
+
+		d.Session.Events.Log(session.WARNING, "Found %d endpoint%s which share%s the same MAC of the gateway (%s), there're might be some IP isolation going on, skipping.", n_gw_shared, a, b, d.Session.Gateway.HwAddress)
+	}
+}
+
+func (d *Discovery) runDiff() {
+	var new net.ArpTable = make(net.ArpTable)
+	var rem net.ArpTable = make(net.ArpTable)
+
+	if d.before != nil {
+		new = net.ArpDiff(d.current, d.before)
+		rem = net.ArpDiff(d.before, d.current)
+	} else {
+		new = d.current
+	}
+
+	if len(new) > 0 || len(rem) > 0 {
+		d.checkShared(new)
+
+		// refresh target pool
+		for ip, mac := range rem {
+			d.Session.Targets.Remove(ip, mac)
+		}
+
+		for ip, mac := range new {
+			d.Session.Targets.AddIfNotExist(ip, mac)
+		}
+	}
+}
+
+func (d *Discovery) Start() error {
+	if d.Running() == false {
+		d.SetRunning(true)
+
+		go func() {
+			for {
+				select {
+				case <-time.After(time.Duration(d.refresh) * time.Second):
+					var err error
+
+					if d.current, err = net.ArpUpdate(d.Session.Interface.Name()); err != nil {
+						d.Session.Events.Log(session.ERROR, "%s", err)
+						continue
+					}
+
+					d.runDiff()
+
+					d.before = d.current
+
+				case <-d.quit:
+					return
+				}
+			}
+		}()
+
+		return nil
+	} else {
+		return fmt.Errorf("Network discovery already started.")
+	}
+}
+
+func (d *Discovery) Show() error {
+	d.Session.Targets.Dump()
+	return nil
+}
+
+func (d *Discovery) Stop() error {
+	if d.Running() == true {
+		d.SetRunning(false)
+		d.quit <- true
+		return nil
+	} else {
+		return fmt.Errorf("Network discovery already stopped.")
+	}
+}