#!/usr/bin/perl -w## see http://search.cpan.org/~atrak/NetPacket-0.04/use strict;BEGIN {	push @INC,"perl";	push @INC,"build/perl";	push @INC,"NetPacket-0.04";};use nfqueue;use NetPacket::IP qw(IP_PROTO_TCP);use NetPacket::TCP;my $debug = 1;my $q;sub cleanup(){	print "unbind\n";	$q->unbind();	print "close\n";	$q->close();}my @http_checks = (	"^GET ",	"^User-Agent",);sub _check_http{	my $data = shift;	foreach my $check (@http_checks) {		return 0 unless ($data =~ /$check/moi);	}	return 1;}sub cb{	my ($dummy,$payload) = @_;	if ($payload) {		print "\n";		my $ip_obj = NetPacket::IP->decode($payload->get_data());		print "Id: " . $payload->swig_id_get() . "\n";		if($ip_obj->{proto} == IP_PROTO_TCP) {			# decode the TCP header			my $tcp_obj = NetPacket::TCP->decode($ip_obj->{data});			if ($tcp_obj->{flags} & NetPacket::TCP::SYN) {				print("$ip_obj->{src_ip} => $ip_obj->{dest_ip} $ip_obj->{proto}\n");				print "TCP src_port: $tcp_obj->{src_port}\n";				print "TCP dst_port: $tcp_obj->{dest_port}\n";				print "TCP flags   : $tcp_obj->{flags}\n";			}			elsif ($tcp_obj->{flags} & NetPacket::TCP::PSH) {				print "TCP data:\n";				print "*" x 50 . "\n";				print $tcp_obj->{data};				print "*" x 50 . "\n";				if ($tcp_obj->{dest_port} == 80) {					_check_http($tcp_obj->{data}) or return $payload->set_verdict($nfqueue::NF_DROP);				}			}		}		print "\n";		$payload->set_verdict($nfqueue::NF_ACCEPT);	}}$q = new nfqueue::queue();print "open\n";$q->open();print "bind\n";$q->bind();$SIG{INT} = "cleanup";#print "set callback, wrong argument type (should fail)\n";#$q->set_callback("blah");print "setting callback\n";$q->set_callback(\&cb);print "creating queue\n";$q->create_queue(0);print "trying to run\n";$q->try_run();