package main

import (
	"dns"
	"flag"
	"fmt"
	"os"
	"strconv"
)

func q(w dns.RequestWriter, m *dns.Msg) {
	w.Send(m)
	r, err := w.Receive()
	if err != nil {
		fmt.Printf("%s\n", err.Error())
	}
	w.Write(r)
}

func main() {
	port := flag.Int("port", 53, "port number to use")
	flag.Usage = func() {
		fmt.Fprintf(os.Stderr, "Usage: %s [-port 53] [@server]\n", os.Args[0])
		flag.PrintDefaults()
	}

	conf, _ := dns.ClientConfigFromFile("/etc/resolv.conf")
	nameserver := "@" + conf.Servers[0]
	flag.Parse()

	for i := 0; i < flag.NArg(); i++ {
		// If it starts with @ it is a nameserver
		if flag.Arg(i)[0] == '@' {
			nameserver = flag.Arg(i)
			break
		}
	}
	nameserver = string([]byte(nameserver)[1:]) // chop off @
	nameserver += ":" + strconv.Itoa(*port)
	c := dns.NewClient()
	fp := new(fingerprint)
	for _, s := range fingerprints() {
		fp.setString(s)
		fp1 := probe(c, nameserver, fp)
		println(s, "|", fp1.String())
	}
}

// A list of all the evil finger prints
func fingerprints() []string {
	return []string{
		".,CH,TXT,QUERY,NOERROR,qr,aa,tc,RD,ra,ad,cd,z,0,0,0,0,DO,4097,NSID",          // general
		"auThoRs.bInD.,CH,TXT,QUERY,NOERROR,qr,aa,tc,rd,ra,ad,cd,z,0,0,0,0,do,0,nsid", // case
		"bind.,NONE,SOA,NOTIFY,NOERROR,qr,AA,tc,RD,ra,ad,cd,Z,0,0,0,0,do,0,nsid",      // notify
	}
}