#!/usr/bin/perl
use IO::Socket;
	&dnsQueryPacket($ARGV[0],$ARGV[1]);

sub dnsQueryPacket{
	my $hostname = $_[0];
	# my @labels = split(/\./, $hostname) ; my $n = scalar(@labels) ; my $question = pack("(C/a*)$n C n2", @labels, 0, 1, 1) ; 
	my @labels;
	my $nlabels = 0;

	my @labels = split(/\./, $hostname) ;
	my $n = scalar(@labels) ;
	my $question = pack("(C/a*)$n C n2", @labels, 0, 1, 1) ;

	$header1 = &dnsheader;
	$server = '130.149.2.12';
	$sock = new IO::Socket::INET
(PeerAddr=>$server,PeerPort=>'53',Proto=>'udp') or die "Can't Connect";
	#sending request
	$sock->send($header1.$question);
	#receiveing request
	$sock->recv($buf,512);
	
	close($sock);
	}

	sub dnsheader{
		$id = 1000;
		$qr_Opcode_aa_tc_rd = '00000000';
		$ra_Z_Rcode = '00000000';
		$Qdcount = 1;
		$Ancount = 0;
		$Nscount = 0;
		$Arcount = 0;
		$header = pack("n,b8,b8,n4",$id++,
					 "$qr_Opcode_aa_tc_rd",#qr,opcode,aa,tc,rd fields
					 "$ra_Z_Rcode",#ra,Z,Rcode fields 
					 "$Qdcount",#one question(Qdcount)
					 "$Ancount",#no answers (ancount)
					 "$Nscount",
					 "$Arcount");#no addtl rr's
		return $header;
	}