dnscrypt-proxy/dnscrypt-proxy/plugin_block_undelegated.go

package main

import (
	"github.com/k-sone/critbitgo"
	"github.com/miekg/dns"
)

var undelegatedSet = []string{
	"0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa.",
	"0.in-addr.arpa.",
	"1.",
	"1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa.",
	"10.in-addr.arpa.",
	"100.100.in-addr.arpa.",
	"100.51.198.in-addr.arpa.",
	"101.100.in-addr.arpa.",
	"102.100.in-addr.arpa.",
	"103.100.in-addr.arpa.",
	"104.100.in-addr.arpa.",
	"105.100.in-addr.arpa.",
	"106.100.in-addr.arpa.",
	"107.100.in-addr.arpa.",
	"108.100.in-addr.arpa.",
	"109.100.in-addr.arpa.",
	"110.100.in-addr.arpa.",
	"111.100.in-addr.arpa.",
	"112.100.in-addr.arpa.",
	"113.0.203.in-addr.arpa.",
	"113.100.in-addr.arpa.",
	"114.100.in-addr.arpa.",
	"115.100.in-addr.arpa.",
	"116.100.in-addr.arpa.",
	"117.100.in-addr.arpa.",
	"118.100.in-addr.arpa.",
	"119.100.in-addr.arpa.",
	"120.100.in-addr.arpa.",
	"121.100.in-addr.arpa.",
	"122.100.in-addr.arpa.",
	"123.100.in-addr.arpa.",
	"124.100.in-addr.arpa.",
	"125.100.in-addr.arpa.",
	"126.100.in-addr.arpa.",
	"127.100.in-addr.arpa.",
	"127.in-addr.arpa.",
	"16.172.in-addr.arpa.",
	"168.192.in-addr.arpa.",
	"17.172.in-addr.arpa.",
	"18.172.in-addr.arpa.",
	"19.172.in-addr.arpa.",
	"2.0.192.in-addr.arpa.",
	"20.172.in-addr.arpa.",
	"21.172.in-addr.arpa.",
	"22.172.in-addr.arpa.",
	"23.172.in-addr.arpa.",
	"24.172.in-addr.arpa.",
	"25.172.in-addr.arpa.",
	"254.169.in-addr.arpa.",
	"255.255.255.255.in-addr.arpa.",
	"26.172.in-addr.arpa.",
	"27.172.in-addr.arpa.",
	"28.172.in-addr.arpa.",
	"29.172.in-addr.arpa.",
	"30.172.in-addr.arpa.",
	"31.172.in-addr.arpa.",
	"64.100.in-addr.arpa.",
	"65.100.in-addr.arpa.",
	"66.100.in-addr.arpa.",
	"67.100.in-addr.arpa.",
	"68.100.in-addr.arpa.",
	"69.100.in-addr.arpa.",
	"70.100.in-addr.arpa.",
	"71.100.in-addr.arpa.",
	"72.100.in-addr.arpa.",
	"73.100.in-addr.arpa.",
	"74.100.in-addr.arpa.",
	"75.100.in-addr.arpa.",
	"76.100.in-addr.arpa.",
	"77.100.in-addr.arpa.",
	"78.100.in-addr.arpa.",
	"79.100.in-addr.arpa.",
	"8.b.d.0.1.0.0.2.ip6.arpa.",
	"8.e.f.ip6.arpa.",
	"80.100.in-addr.arpa.",
	"81.100.in-addr.arpa.",
	"82.100.in-addr.arpa.",
	"83.100.in-addr.arpa.",
	"84.100.in-addr.arpa.",
	"85.100.in-addr.arpa.",
	"86.100.in-addr.arpa.",
	"87.100.in-addr.arpa.",
	"88.100.in-addr.arpa.",
	"89.100.in-addr.arpa.",
	"9.e.f.ip6.arpa.",
	"90.100.in-addr.arpa.",
	"91.100.in-addr.arpa.",
	"92.100.in-addr.arpa.",
	"93.100.in-addr.arpa.",
	"94.100.in-addr.arpa.",
	"95.100.in-addr.arpa.",
	"96.100.in-addr.arpa.",
	"97.100.in-addr.arpa.",
	"98.100.in-addr.arpa.",
	"99.100.in-addr.arpa.",
	"a.e.f.ip6.arpa.",
	"airdream.",
	"api.",
	"b.e.f.ip6.arpa.",
	"bbrouter.",
	"belkin.",
	"blinkap.",
	"corp.",
	"d.f.ip6.arpa.",
	"davolink.",
	"dearmyrouter.",
	"dhcp.",
	"dlink.",
	"domain.",
	"envoy.",
	"example.",
	"f.f.ip6.arpa.",
	"grp.",
	"gw==.",
	"home.",
	"hub.",
	"internal.",
	"intra.",
	"invalid.",
	"ksyun.",
	"lan.",
	"loc.",
	"local.",
	"localdomain.",
	"localnet.",
	"modem.",
	"mynet.",
	"myrouter.",
	"novalocal.",
	"openstacklocal.",
	"priv.",
	"prv.",
	"router.",
	"telus.",
	"test.",
	"totolink.",
	"wlan_ap.",
	"workgroup.",
	"zghjccbob3n0.",
}

type PluginBlockUndelegated struct {
	suffixes *critbitgo.Trie
}

func (plugin *PluginBlockUndelegated) Name() string {
	return "block_undelegated"
}

func (plugin *PluginBlockUndelegated) Description() string {
	return "Block undelegated DNS names"
}

func (plugin *PluginBlockUndelegated) Init(proxy *Proxy) error {
	suffixes := critbitgo.NewTrie()
	for _, line := range undelegatedSet {
		pattern := StringReverse(line)
		suffixes.Insert([]byte(pattern), true)
	}
	plugin.suffixes = suffixes
	return nil
}

func (plugin *PluginBlockUndelegated) Drop() error {
	return nil
}

func (plugin *PluginBlockUndelegated) Reload() error {
	return nil
}

func (plugin *PluginBlockUndelegated) Eval(pluginsState *PluginsState, msg *dns.Msg) error {
	revQname := StringReverse(pluginsState.qName)
	match, _, found := plugin.suffixes.LongestPrefix([]byte(revQname))
	if !found {
		return nil
	}
	if len(match) == len(revQname) || revQname[len(match)] == '.' {
		synth := EmptyResponseFromMessage(msg)
		synth.Rcode = dns.RcodeNameError
		pluginsState.synthResponse = synth
		pluginsState.action = PluginsActionSynth
		pluginsState.returnCode = PluginsReturnCodeSynth
	}
	return nil
}