new: implemented syn.scan module (closes #67)

modules/syn_scan.go

@@ -0,0 +1,254 @@
+package modules
+
+import (
+	"fmt"
+	"net"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/evilsocket/bettercap-ng/core"
+	"github.com/evilsocket/bettercap-ng/log"
+	"github.com/evilsocket/bettercap-ng/network"
+	"github.com/evilsocket/bettercap-ng/packets"
+	"github.com/evilsocket/bettercap-ng/session"
+
+	"github.com/google/gopacket"
+	"github.com/google/gopacket/layers"
+
+	"github.com/malfunkt/iprange"
+)
+
+const synSourcePort = 666
+
+type SynScanner struct {
+	session.SessionModule
+	addresses []net.IP
+	startPort int
+	endPort   int
+}
+
+func NewSynScanner(s *session.Session) *SynScanner {
+	ss := &SynScanner{
+		SessionModule: session.NewSessionModule("syn.scan", s),
+		addresses:     make([]net.IP, 0),
+		startPort:     0,
+		endPort:       0,
+	}
+
+	ss.AddHandler(session.NewModuleHandler("syn.scan IP-RANGE START-PORT END-PORT", "syn.scan ([^\\s]+) (\\d+)([\\s\\d]*)",
+		"Perform a syn port scanning against an IP address within the provided ports range.",
+		func(args []string) error {
+			var err error
+
+			list, err := iprange.Parse(args[0])
+			if err != nil {
+				return fmt.Errorf("Error while parsing IP range '%s': %s", args[0], err)
+			}
+
+			ss.addresses = list.Expand()
+			ss.startPort = 0
+			ss.endPort = 0
+
+			if ss.startPort, err = strconv.Atoi(core.Trim(args[1])); err != nil {
+				return fmt.Errorf("Invalid START-PORT: %s", err)
+			}
+
+			if ss.startPort > 65535 {
+				ss.startPort = 65535
+			}
+			ss.endPort = ss.startPort
+
+			argc := len(args)
+			if argc > 2 && core.Trim(args[2]) != "" {
+				if ss.endPort, err = strconv.Atoi(core.Trim(args[2])); err != nil {
+					return fmt.Errorf("Invalid END-PORT: %s", err)
+				}
+			}
+
+			if ss.endPort < ss.startPort {
+				return fmt.Errorf("END-PORT is greater than START-PORT")
+			}
+
+			return ss.synScan()
+		}))
+
+	return ss
+}
+
+func (s *SynScanner) Name() string {
+	return "syn.scan"
+}
+
+func (s *SynScanner) Description() string {
+	return "A module to perform SYN port scanning."
+}
+
+func (s *SynScanner) Author() string {
+	return "Simone Margaritelli <evilsocket@protonmail.com>"
+}
+
+func (s *SynScanner) Configure() error {
+	return nil
+}
+
+func (s *SynScanner) Start() error {
+	return nil
+}
+
+func (s *SynScanner) Stop() error {
+	return nil
+}
+
+func (s *SynScanner) getMAC(ip net.IP, probe bool) (net.HardwareAddr, error) {
+	var mac string
+	var hw net.HardwareAddr
+	var err error
+
+	// do we have this ip mac address?
+	mac, err = network.ArpLookup(s.Session.Interface.Name(), ip.String(), false)
+	if err != nil && probe == true {
+		from := s.Session.Interface.IP
+		from_hw := s.Session.Interface.HW
+
+		if err, probe := packets.NewUDPProbe(from, from_hw, ip, 139); err != nil {
+			log.Error("Error while creating UDP probe packet for %s: %s", ip.String(), err)
+		} else {
+			s.Session.Queue.Send(probe)
+		}
+
+		time.Sleep(500 * time.Millisecond)
+
+		mac, err = network.ArpLookup(s.Session.Interface.Name(), ip.String(), false)
+	}
+
+	if mac == "" {
+		return nil, fmt.Errorf("Could not find hardware address for %s.", ip.String())
+	}
+
+	mac = network.NormalizeMac(mac)
+	hw, err = net.ParseMAC(mac)
+	if err != nil {
+		return nil, fmt.Errorf("Error while parsing hardware address '%s' for %s: %s", mac, ip.String(), err)
+	}
+
+	return hw, nil
+}
+
+func (s *SynScanner) inRange(ip net.IP) bool {
+	for _, a := range s.addresses {
+		if a.Equal(ip) {
+			return true
+		}
+	}
+	return false
+}
+
+func (s *SynScanner) onPacket(pkt gopacket.Packet) {
+	var eth layers.Ethernet
+	var ip layers.IPv4
+	var tcp layers.TCP
+	foundLayerTypes := []gopacket.LayerType{}
+
+	parser := gopacket.NewDecodingLayerParser(
+		layers.LayerTypeEthernet,
+		&eth,
+		&ip,
+		&tcp,
+	)
+
+	err := parser.DecodeLayers(pkt.Data(), &foundLayerTypes)
+	if err != nil {
+		return
+	}
+
+	if s.inRange(ip.SrcIP) && tcp.DstPort == synSourcePort && tcp.SYN && tcp.ACK {
+		from := ip.SrcIP.String()
+
+		log.Info("Found open port %d for %s", tcp.SrcPort, core.Bold(from))
+
+		var host *network.Endpoint
+
+		if ip.SrcIP.Equal(s.Session.Interface.IP) {
+			host = s.Session.Interface
+		} else if ip.SrcIP.Equal(s.Session.Gateway.IP) {
+			host = s.Session.Gateway
+		} else {
+			host = s.Session.Lan.GetByIp(from)
+		}
+
+		if host != nil {
+			sports := strings.Split(host.Meta.Get("tcp-ports").(string), ",")
+			ports := []int{int(tcp.SrcPort)}
+
+			for _, s := range sports {
+				n, err := strconv.Atoi(s)
+				if err == nil {
+					ports = append(ports, n)
+				}
+			}
+
+			ports = core.UniqueInts(ports, true)
+			list := make([]string, len(ports))
+			for i, p := range ports {
+				list[i] = fmt.Sprintf("%d", p)
+			}
+
+			host.Meta.Set("tcp-ports", strings.Join(list, ","))
+		}
+	}
+}
+
+func (s *SynScanner) synScan() error {
+	if s.Running() == true {
+		return fmt.Errorf("A scan is already running, wait for it to end before starting a new one.")
+	}
+
+	s.SetRunning(true, func() {
+		defer s.SetRunning(false, nil)
+
+		naddrs := len(s.addresses)
+		plural := "es"
+		if naddrs == 1 {
+			plural = ""
+		}
+
+		if s.startPort != s.endPort {
+			log.Info("SYN scanning %d address%s from port %d to port %d ...", naddrs, plural, s.startPort, s.endPort)
+		} else {
+			log.Info("SYN scanning %d address%s on port %d ...", naddrs, plural, s.startPort)
+		}
+
+		// set the collector
+		s.Session.Queue.OnPacket(s.onPacket)
+		defer s.Session.Queue.OnPacket(nil)
+
+		// start sending SYN packets and wait
+		for _, address := range s.addresses {
+			mac, err := s.getMAC(address, true)
+			if err != nil {
+				log.Debug("Could not get MAC for %s: %s", address.String(), err)
+				continue
+			}
+
+			for dstPort := s.startPort; dstPort < s.endPort+1; dstPort++ {
+				err, raw := packets.NewTCPSyn(s.Session.Interface.IP, s.Session.Interface.HW, address, mac, synSourcePort, dstPort)
+				if err != nil {
+					log.Error("Error creating SYN packet: %s", err)
+					continue
+				}
+
+				if err := s.Session.Queue.Send(raw); err != nil {
+					log.Error("Error sending SYN packet: %s", err)
+				} else {
+					log.Debug("Sent %d bytes of SYN packet to %s for port %d", len(raw), address.String(), dstPort)
+				}
+			}
+		}
+
+		nports := s.endPort - s.startPort + 1
+		time.Sleep(time.Duration(nports*500) * time.Millisecond)
+	})
+
+	return nil
+}