new: new net.probe.upnp agent

modules/net_probe.go

@@ -15,6 +15,7 @@ import (
 type Probes struct {
 	NBNS bool
 	MDNS bool
+	UPNP bool
 }
 
 type Prober struct {
@@ -38,6 +39,10 @@ func NewProber(s *session.Session) *Prober {
 		"true",
 		"Enable mDNS discovery probes."))
 
+	p.AddParam(session.NewBoolParameter("net.probe.upnp",
+		"true",
+		"Enable UPNP discovery probes."))
+
 	p.AddParam(session.NewIntParameter("net.probe.throttle",
 		"10",
 		"If greater than 0, probe packets will be throttled by this value in milliseconds."))
@@ -89,6 +94,8 @@ func (p *Prober) Configure() error {
 		return err
 	} else if err, p.probes.MDNS = p.BoolParam("net.probe.mdns"); err != nil {
 		return err
+	} else if err, p.probes.UPNP = p.BoolParam("net.probe.upnp"); err != nil {
+		return err
 	} else {
 		log.Debug("Throttling packets of %d ms.", p.throttle)
 	}
@@ -124,6 +131,10 @@ func (p *Prober) Start() error {
 				p.sendProbeMDNS(from, from_hw)
 			}
 
+			if p.probes.UPNP {
+				p.sendProbeUPNP(from, from_hw)
+			}
+
 			for _, ip := range addresses {
 				if !p.Running() {
 					return

modules/net_probe_upnp.go

@@ -0,0 +1,20 @@
+package modules
+
+import (
+	"net"
+
+	"github.com/bettercap/bettercap/log"
+	"github.com/bettercap/bettercap/packets"
+)
+
+func (p *Prober) sendProbeUPNP(from net.IP, from_hw net.HardwareAddr) {
+	err, raw := packets.NewUPNPProbe(from, from_hw)
+	if err != nil {
+		log.Error("error while sending upnp probe: %v", err)
+		return
+	} else if err := p.Session.Queue.Send(raw); err != nil {
+		log.Error("error sending upnp packet: %s", err)
+	} else {
+		log.Debug("sent %d bytes of UPNP probe", len(raw))
+	}
+}

packets/upnp.go

@@ -0,0 +1,52 @@
+package packets
+
+import (
+	"fmt"
+	"net"
+
+	"github.com/google/gopacket"
+	"github.com/google/gopacket/layers"
+)
+
+const (
+	UPNPPort = 1900
+)
+
+var (
+	UPNPDestMac = net.HardwareAddr{0x01, 0x00, 0x5e, 0x00, 0x00, 0xfb}
+	UPNPDestIP  = net.ParseIP("239.255.255.250")
+)
+
+func NewUPNPProbe(from net.IP, from_hw net.HardwareAddr) (error, []byte) {
+	eth := layers.Ethernet{
+		SrcMAC:       from_hw,
+		DstMAC:       UPNPDestMac,
+		EthernetType: layers.EthernetTypeIPv4,
+	}
+
+	ip4 := layers.IPv4{
+		Protocol: layers.IPProtocolUDP,
+		Version:  4,
+		TTL:      64,
+		SrcIP:    from,
+		DstIP:    UPNPDestIP,
+	}
+
+	udp := layers.UDP{
+		SrcPort: layers.UDPPort(12345),
+		DstPort: layers.UDPPort(UPNPPort),
+	}
+
+	payload := []byte("M-SEARCH * HTTP/1.1\r\n" +
+		fmt.Sprintf("Host: %s:%d\r\n", UPNPDestIP, UPNPPort) +
+		"Man: ssdp:discover\r\n" +
+		"ST: ssdp:all\r\n" +
+		"MX: 2\r\n" +
+		"\r\n")
+
+	if err := udp.SetNetworkLayerForChecksum(&ip4); err != nil {
+		return err, nil
+	}
+
+	return Serialize(&eth, &ip4, &udp, gopacket.Payload(payload))
+}