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-rw-r--r--bin/tests/system/digdelv/ans5/ans.pl176
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diff --git a/bin/tests/system/digdelv/ans5/ans.pl b/bin/tests/system/digdelv/ans5/ans.pl
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+#!/usr/bin/perl
+
+# Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+#
+# SPDX-License-Identifier: MPL-2.0
+#
+# 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 https://mozilla.org/MPL/2.0/.
+#
+# See the COPYRIGHT file distributed with this work for additional
+# information regarding copyright ownership.
+
+# This is a TCP-only DNS server whose aim is to facilitate testing how dig
+# copes with prematurely closed TCP connections.
+#
+# This server can be configured (through a separate control socket) with a
+# series of responses to send for subsequent incoming TCP DNS queries. Only
+# one query is handled before closing each connection. In order to keep things
+# simple, the server is not equipped with any mechanism for handling malformed
+# queries.
+#
+# Available response types are defined in the %response_types hash in the
+# getAnswerSection() function below. Each RR returned is generated dynamically
+# based on the QNAME found in the incoming query.
+
+use IO::File;
+use Net::DNS;
+use Net::DNS::Packet;
+
+use strict;
+
+# Ignore SIGPIPE so we won't fail if peer closes a TCP socket early
+local $SIG{PIPE} = 'IGNORE';
+
+# Flush logged output after every line
+local $| = 1;
+
+my $server_addr = "10.53.0.5";
+if (@ARGV > 0) {
+ $server_addr = @ARGV[0];
+}
+
+my $mainport = int($ENV{'PORT'});
+if (!$mainport) { $mainport = 5300; }
+my $ctrlport = int($ENV{'EXTRAPORT1'});
+if (!$ctrlport) { $ctrlport = 5301; }
+
+my $ctlsock = IO::Socket::INET->new(LocalAddr => "$server_addr",
+ LocalPort => $ctrlport, Proto => "tcp", Listen => 5, Reuse => 1) or die "$!";
+
+my $tcpsock = IO::Socket::INET->new(LocalAddr => "$server_addr",
+ LocalPort => $mainport, Proto => "tcp", Listen => 5, Reuse => 1) or die "$!";
+
+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 @response_sequence = ("complete_axfr");
+my $connection_counter = 0;
+
+# Return the next answer type to send, incrementing the connection counter and
+# making sure the latter does not exceed the size of the array holding the
+# configured response sequence.
+sub getNextResponseType {
+ my $response_type = $response_sequence[$connection_counter];
+
+ $connection_counter++;
+ $connection_counter %= scalar(@response_sequence);
+
+ return $response_type;
+}
+
+# Return an array of resource records comprising the answer section of a given
+# response type.
+sub getAnswerSection {
+ my ($response_type, $qname) = @_;
+
+ my %response_types = (
+ no_response => [],
+
+ partial_axfr => [
+ Net::DNS::RR->new("$qname 300 IN SOA . . 0 0 0 0 300"),
+ Net::DNS::RR->new("$qname NS ."),
+ ],
+
+ complete_axfr => [
+ Net::DNS::RR->new("$qname 300 IN SOA . . 0 0 0 0 300"),
+ Net::DNS::RR->new("$qname NS ."),
+ Net::DNS::RR->new("$qname 300 IN SOA . . 0 0 0 0 300"),
+ ],
+ );
+
+ return $response_types{$response_type};
+}
+
+
+# Generate a Net::DNS::Packet containing the response to send on the current
+# TCP connection. If the answer section of the response is determined to be
+# empty, no data will be sent on the connection at all (immediate EOF).
+sub generateResponse {
+ my ($buf) = @_;
+ my $request;
+
+ if ($Net::DNS::VERSION > 0.68) {
+ $request = new Net::DNS::Packet(\$buf, 0);
+ $@ and die $@;
+ } else {
+ my $err;
+ ($request, $err) = new Net::DNS::Packet(\$buf, 0);
+ $err and die $err;
+ }
+
+ my @questions = $request->question;
+ my $qname = $questions[0]->qname;
+ my $qtype = $questions[0]->qtype;
+ my $qclass = $questions[0]->qclass;
+ my $id = $request->header->id;
+
+ my $packet = new Net::DNS::Packet($qname, $qtype, $qclass);
+ $packet->header->qr(1);
+ $packet->header->aa(1);
+ $packet->header->id($id);
+
+ my $response_type = getNextResponseType();
+ my $answers = getAnswerSection($response_type, $qname);
+ for my $rr (@$answers) {
+ $packet->push("answer", $rr);
+ }
+
+ print " Sending \"$response_type\" response\n";
+
+ return $packet->data if @$answers;
+}
+
+my $rin;
+my $rout;
+for (;;) {
+ $rin = '';
+ vec($rin, fileno($ctlsock), 1) = 1;
+ vec($rin, fileno($tcpsock), 1) = 1;
+
+ select($rout = $rin, undef, undef, undef);
+
+ if (vec($rout, fileno($ctlsock), 1)) {
+ my $conn = $ctlsock->accept;
+ @response_sequence = split(' ', $conn->getline);
+ $connection_counter = 0;
+ print "Response sequence set to: @response_sequence\n";
+ $conn->close;
+ } elsif (vec($rout, fileno($tcpsock), 1)) {
+ my $buf;
+ my $lenbuf;
+ my $conn = $tcpsock->accept;
+ my $n = $conn->sysread($lenbuf, 2);
+ die unless $n == 2;
+ my $len = unpack("n", $lenbuf);
+ $n = $conn->sysread($buf, $len);
+ die unless $n == $len;
+ print "TCP request\n";
+ my $response = generateResponse($buf);
+ if ($response) {
+ $len = length($response);
+ $n = $conn->syswrite(pack("n", $len), 2);
+ $n = $conn->syswrite($response, $len);
+ print " Sent: $n chars via TCP\n";
+ } else {
+ print " No response sent\n";
+ }
+ $conn->close;
+ }
+}