1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
|
#!/usr/bin/env perl
#
# Copyright (C) Internet Systems Consortium, Inc. ("ISC")
#
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
#
# See the COPYRIGHT file distributed with this work for additional
# information regarding copyright ownership.
use strict;
use warnings;
use IO::File;
use Getopt::Long;
use Net::DNS::Nameserver;
my $pidf = new IO::File "ans.pid", "w" or die "cannot open pid file: $!";
print $pidf "$$\n" or die "cannot write pid file: $!";
$pidf->close or die "cannot close pid file: $!";
sub rmpid { unlink "ans.pid"; exit 1; };
$SIG{INT} = \&rmpid;
$SIG{TERM} = \&rmpid;
my $localaddr = "10.53.0.3";
my $localport = int($ENV{'PORT'});
if (!$localport) { $localport = 5300; }
my $verbose = 0;
my $ttl = 60;
my $zone = "example.broken";
my $nsname = "ns3.$zone";
my $synth = "synth-then-dname.$zone";
my $synth2 = "synth2-then-dname.$zone";
sub reply_handler {
my ($qname, $qclass, $qtype, $peerhost, $query, $conn) = @_;
my ($rcode, @ans, @auth, @add);
print ("request: $qname/$qtype\n");
STDOUT->flush();
if ($qname eq "example.broken") {
if ($qtype eq "SOA") {
my $rr = new Net::DNS::RR("$qname $ttl $qclass SOA . . 0 0 0 0 0");
push @ans, $rr;
} elsif ($qtype eq "NS") {
my $rr = new Net::DNS::RR("$qname $ttl $qclass NS $nsname");
push @ans, $rr;
$rr = new Net::DNS::RR("$nsname $ttl $qclass A $localaddr");
push @add, $rr;
}
$rcode = "NOERROR";
} elsif ($qname eq "cname-to-$synth2") {
my $rr = new Net::DNS::RR("$qname $ttl $qclass CNAME name.$synth2");
push @ans, $rr;
$rr = new Net::DNS::RR("name.$synth2 $ttl $qclass CNAME name");
push @ans, $rr;
$rr = new Net::DNS::RR("$synth2 $ttl $qclass DNAME .");
push @ans, $rr;
$rcode = "NOERROR";
} elsif ($qname eq "$synth" || $qname eq "$synth2") {
if ($qtype eq "DNAME") {
my $rr = new Net::DNS::RR("$qname $ttl $qclass DNAME .");
push @ans, $rr;
}
$rcode = "NOERROR";
} elsif ($qname eq "name.$synth") {
my $rr = new Net::DNS::RR("$qname $ttl $qclass CNAME name.");
push @ans, $rr;
$rr = new Net::DNS::RR("$synth $ttl $qclass DNAME .");
push @ans, $rr;
$rcode = "NOERROR";
} elsif ($qname eq "name.$synth2") {
my $rr = new Net::DNS::RR("$qname $ttl $qclass CNAME name.");
push @ans, $rr;
$rr = new Net::DNS::RR("$synth2 $ttl $qclass DNAME .");
push @ans, $rr;
$rcode = "NOERROR";
} else {
$rcode = "REFUSED";
}
return ($rcode, \@ans, \@auth, \@add, { aa => 1 });
}
GetOptions(
'port=i' => \$localport,
'verbose!' => \$verbose,
);
my $ns = Net::DNS::Nameserver->new(
LocalAddr => $localaddr,
LocalPort => $localport,
ReplyHandler => \&reply_handler,
Verbose => $verbose,
);
$ns->main_loop;
|