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package dnsd; |
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|
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use warnings; |
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use strict; |
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|
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use Net::DNS::Nameserver; |
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use Net::DNS::Resolver; |
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use Data::Dump qw/dump/; |
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use CouchDB; |
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|
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use server; |
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use client; |
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our $debug = server::debug; |
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|
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my $res = Net::DNS::Resolver->new( |
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# nameserver => [ '10.60.0.1' ], |
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recurse => 1, |
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debug => $debug, |
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); |
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|
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our ( $ptr_cache, $a_cache ); |
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sub name_ip { |
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my ( $name, $ip ) = @_; |
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$ptr_cache->{ join('.', reverse split(/\./, $ip)) } = $name; |
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$a_cache->{$name} = $ip; |
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return $ip; |
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} |
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|
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name_ip 'server' => $server::ip; |
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|
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foreach my $ip ( client::all_ips ) { |
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if ( my $name = client::conf( $ip => 'hostname' ) ) { |
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name_ip $name => $ip; |
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} |
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} |
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|
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sub reply_handler { |
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my ($qname, $qclass, $qtype, $peerhost,$query,$conn) = @_; |
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my ($rcode, @ans, @auth, @add); |
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|
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$debug = server::debug; |
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|
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my $audit = { |
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qname => $qname, |
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qclass => $qclass, |
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qtype => $qtype, |
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peerhost => $peerhost, |
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sockhost => $conn->{"sockhost"}, |
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source => 'unknown', |
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}; |
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|
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$query->print if $debug; |
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|
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my $local = $1 if $qname =~ m{^(.+)\.\Q$server::domain\E$}; |
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$local = $qname if $qname !~ m{\.}; |
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|
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my $ttl = 3600; |
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|
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if ( $local ) { |
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warn "local[$local] $qname $qtype"; |
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$rcode = "NOERROR"; |
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my $rdata; |
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if ( $qtype eq "A" ) { |
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if ( $rdata = $a_cache->{$local} ) { |
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$audit->{source} = 'local'; |
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} else { |
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$rcode = "NXDOMAIN"; |
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warn "## no $local in ",dump( $a_cache ); |
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} |
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} elsif ( $qtype eq 'PTR' ) { |
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$qname =~ s{\.in-addr\.arpa$}{} || warn "W: can't strip suffix from $qtype $qname"; |
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if ( my $rdata = $ptr_cache->{$qname} ) { |
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$rdata .= '.' . $server::domain; |
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push @ans, Net::DNS::RR->new("$qname $ttl $qclass $qtype $rdata"); |
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$audit->{source} = 'PTR'; |
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} else { |
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warn "## no $qname in ",dump( $ptr_cache ); |
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$rcode = "NXDOMAIN"; |
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} |
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} else { |
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$audit->{warn} = "qtype $qtype not supported"; |
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} |
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|
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push @ans, Net::DNS::RR->new("$qname $ttl $qclass $qtype $rdata") if $ttl; |
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|
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} elsif ( my $packet = $res->query( $qname, $qtype ) ) { |
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|
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$audit->{source} = 'upstream'; |
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$packet->print; |
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push @ans, $_ foreach $packet->answer; |
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$rcode = "NOERROR"; |
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|
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} else { |
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# not found |
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$rcode = "NXDOMAIN"; |
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} |
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|
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warn "rcode: $rcode ",dump( @ans ); |
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|
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$audit->{rcode} = $rcode; |
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$audit->{ans} = [ map { |
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my $data; |
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foreach my $n ( keys %$_ ) { |
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$data->{$n} = $_->{$n}; |
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} |
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$data; |
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} @ans ]; |
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|
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CouchDB::audit( 'response', $audit ); |
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|
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# mark the answer as authoritive (by setting the 'aa' flag |
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return ($rcode, \@ans, \@auth, \@add, { aa => 1 }); |
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} |
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|
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sub start { |
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my $ns = Net::DNS::Nameserver->new( |
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LocalPort => 53, |
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ReplyHandler => sub { |
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server->refresh; |
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reply_handler(@_); |
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}, |
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Verbose => $debug, |
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) || die "couldn't create nameserver object\n"; |
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|
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CouchDB::audit('start', { port => 53, domain => $server::domain }); |
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warn "DNS $server::domain"; |
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|
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$ns->main_loop; |
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} |
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|
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1; |