bettercap/packets/mdns.go
2018-08-29 17:51:02 +03:00

29 lines
701 B
Go

package packets
import (
"github.com/google/gopacket"
"github.com/google/gopacket/layers"
"github.com/miekg/dns"
)
const MDNSPort = 5353
func MDNSGetHostname(pkt gopacket.Packet) string {
if ludp := pkt.Layer(layers.LayerTypeUDP); ludp != nil {
if udp := ludp.(*layers.UDP); udp != nil && udp.SrcPort == MDNSPort && udp.DstPort == MDNSPort {
var msg dns.Msg
if err := msg.Unpack(udp.Payload); err == nil && msg.Opcode == dns.OpcodeQuery && len(msg.Answer) > 0 {
for _, answer := range append(msg.Answer, msg.Extra...) {
switch rr := answer.(type) {
case *dns.PTR:
case *dns.A:
case *dns.AAAA:
return rr.Header().Name
}
}
}
}
}
return ""
}