81 lines
1.9 KiB
Perl
81 lines
1.9 KiB
Perl
#!/usr/bin/perl -w
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# Copyright (C) Internet Systems Consortium, Inc. ("ISC")
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#
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# SPDX-License-Identifier: MPL-2.0
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#
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# This Source Code Form is subject to the terms of the Mozilla Public
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# License, v. 2.0. If a copy of the MPL was not distributed with this
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# file, you can obtain one at https://mozilla.org/MPL/2.0/.
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#
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# See the COPYRIGHT file distributed with this work for additional
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# information regarding copyright ownership.
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#
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# Don't respond if the "norespond" file exists; otherwise respond to
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# any A or AAAA query.
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#
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use IO::File;
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use IO::Socket;
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use Net::DNS;
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use Net::DNS::Packet;
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my $localport = int($ENV{'PORT'});
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if (!$localport) { $localport = 5300; }
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my $sock = IO::Socket::INET->new(LocalAddr => "10.53.0.5",
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LocalPort => $localport, Proto => "udp") or die "$!";
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my $pidf = new IO::File "ans.pid", "w" or die "cannot open pid file: $!";
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print $pidf "$$\n" or die "cannot write pid file: $!";
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$pidf->close or die "cannot close pid file: $!";
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sub rmpid { unlink "ans.pid"; exit 1; };
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$SIG{INT} = \&rmpid;
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$SIG{TERM} = \&rmpid;
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my $octet = 0;
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for (;;) {
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$sock->recv($buf, 512);
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print "**** request from " , $sock->peerhost, " port ", $sock->peerport, "\n";
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my $packet;
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if ($Net::DNS::VERSION > 0.68) {
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$packet = new Net::DNS::Packet(\$buf, 0);
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$@ and die $@;
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} else {
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my $err;
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($packet, $err) = new Net::DNS::Packet(\$buf, 0);
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$err and die $err;
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}
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print "REQUEST:\n";
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$packet->print;
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$packet->header->qr(1);
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my @questions = $packet->question;
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my $qname = $questions[0]->qname;
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my $qtype = $questions[0]->qtype;
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$packet->header->aa(1);
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if ($qtype eq "A") {
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$packet->push("answer",
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new Net::DNS::RR($qname .
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" 0 A 192.0.2." . $octet));
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$octet = $octet + 1;
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} elsif ($qtype eq "AAAA") {
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$packet->push("answer",
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new Net::DNS::RR($qname .
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" 300 AAAA 2001:db8:beef::1"));
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}
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$sock->send($packet->data);
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print "RESPONSE:\n";
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$packet->print;
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print "\n";
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}
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