#
# Shorewall 3.9 -- /usr/share/shorewall/Shorewall/Tunnels.pm
#
#     This program is under GPL [http://www.gnu.org/copyleft/gpl.htm]
#
#     (c) 2007 - Tom Eastep (teastep@shorewall.net)
#
#       Complete documentation is available at http://shorewall.net
#
#       This program is free software; you can redistribute it and/or modify
#       it under the terms of Version 2 of the GNU General Public License
#       as published by the Free Software Foundation.
#
#       This program is distributed in the hope that it will be useful,
#       but WITHOUT ANY WARRANTY; without even the implied warranty of
#       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
#       GNU General Public License for more details.
#
#       You should have received a copy of the GNU General Public License
#       along with this program; if not, write to the Free Software
#       Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA
#
#
package Shorewall::Tunnels;
require Exporter;
use Shorewall::Common;
use Shorewall::Config;
use Shorewall::Zones;
use Shorewall::Chains;

use strict;

our @ISA = qw(Exporter);
our @EXPORT = qw( setup_tunnels );
our @EXPORT_OK = ( );
our @VERSION = 1.00;

#
# Here starts the tunnel stuff -- we really should get rid of this crap...
#
sub setup_tunnels() {

    sub setup_one_ipsec {
	my ($inchainref, $outchainref, $kind, $source, $dest, $gatewayzones) = @_;

	( $kind, my $qualifier ) = split /:/, $kind;

	fatal_error "Invalid IPSEC modifier ($qualifier) in tunnel \"$line\"" if $qualifier && ( $qualifier ne 'noah' );
	
	my $noah = $qualifier || ($kind ne 'ipsec' );

	my $options = '-m $state --state NEW -j ACCEPT';
	
	add_rule $inchainref,  "-p 50 $source -j ACCEPT"; 
	add_rule $outchainref, "-p 50 $dest   -j ACCEPT"; 
	
	unless ( $noah ) {
	    add_rule $inchainref,  "-p 51 $source -j ACCEPT"; 
	    add_rule $outchainref, "-p 51 $dest   -j ACCEPT"; 
	}
	
	add_rule $outchainref,  "-p udp $dest --dport 500 $options";
	
	if ( $kind eq 'ipsec' ) {
	    add_rule $inchainref, "-p udp $source --dport $options";
	} else {
	    add_rule $inchainref, "-p udp $source -m multiport --dports 500,4500 $options";
	}
	
	for my $zone ( split /,/, $gatewayzones ) {
	    fatal_error "Invalid zone ($zone) in tunnel \"$line\"" unless $zones{$zone}{type} eq 'ipv4';
	    $inchainref  = ensure_filter_chain "${zone}2${firewall_zone}", 1;
	    $outchainref = ensure_filter_chain "${firewall_zone}2${zone}", 1;
	    
	    unless ( $capabilities{POLICY_MATCH} ) {
		add_rule $inchainref,  "-p 50 $source -j ACCEPT";
		add_rule $outchainref, "-p 50 $dest -j ACCEPT";
		
		unless ( $noah ) {
		    add_rule $inchainref,  "-p 51 $source -j ACCEPT";
		    add_rule $outchainref, "-p 51 $dest -j ACCEPT";
		}
	    }
	    
	    if ( $kind eq 'ipsec' ) {
		add_rule $inchainref,  "-p udp $source --dport 500 $options";
		add_rule $outchainref, "-p udp $dest --dport 500 $options";
	    } else {
		add_rule $inchainref,  "-p udp $source -m multiport --dports 500,4500 $options";
		add_rule $outchainref, "-p udp $dest -m multiport --dports 500,4500 $options";
	    }
	}
    }
    
    sub setup_one_other {
	my ($inchainref, $outchainref, $kind, $source, $dest , $protocol) = @_;
	
	add_rule $inchainref ,  "-p $protocol $source -j ACCEPT";
	add_rule $outchainref , "-p $protocol $dest -j ACCEPT";
    }
    
    sub setup_pptp_client {
	my ($inchainref, $outchainref, $kind, $source, $dest ) = @_;
	
	add_rule $outchainref,  "-p 47 $dest -j ACCEPT";
	add_rule $inchainref,   "-p 47 $source -j ACCEPT";
	add_rule $outchainref,  "-p tcp --dport 1723 $dest -j ACCEPT"
	}
    
    sub setup_pptp_server {
	my ($inchainref, $outchainref, $kind, $source, $dest ) = @_;
	
	add_rule $inchainref,  "-p 47 $dest -j ACCEPT";
	add_rule $outchainref, "-p 47 $source -j ACCEPT";
	add_rule $inchainref,  "-p tcp --dport 1723 $dest -j ACCEPT"
	}
    
    sub setup_one_openvpn {
	my ($inchainref, $outchainref, $kind, $source, $dest) = @_;
	
	my $protocol = 'udp';
	my $port     = 1194;
	
	( $kind, my ( $proto, $p ) ) = split /:/, $kind;
	
	$port     = $p     if $p;
	$protocol = $proto if $proto;
	
	add_rule $inchainref,  "-p $protocol $source --dport $port -j ACCEPT";
	add_rule $outchainref, "-p $protocol $dest --dport $port -j ACCEPT";
    }

    sub setup_one_openvpn_client {
	my ($inchainref, $outchainref, $kind, $source, $dest) = @_;
	
	my $protocol = 'udp';
	my $port     = 1194;
	
	( $kind, my ( $proto, $p ) ) = split /:/, $kind;
	
	$port     = $p     if $p;
	$protocol = $proto if $proto;
	
	add_rule $inchainref,  "-p $protocol $source --sport $port -j ACCEPT";
	add_rule $outchainref, "-p $protocol $dest --dport $port -j ACCEPT";
    }

    sub setup_one_openvpn_server {
	my ($inchainref, $outchainref, $kind, $source, $dest) = @_;
	
	my $protocol = 'udp';
	my $port     = 1194;
	
	( $kind, my ( $proto, $p ) ) = split /:/, $kind;
	
	$port     = $p     if $p;
	$protocol = $proto if $proto;

	add_rule $inchainref,  "-p $protocol $source --dport $port -j ACCEPT";
	add_rule $outchainref, "-p $protocol $dest --sport $port -j ACCEPT";
    }

    sub setup_one_generic {
	my ($inchainref, $outchainref, $kind, $source, $dest) = @_;
	
	my $protocol = 'udp';
	my $port     = '--dport 5000';
	
	if ( $kind =~ /.*:.*:.*/ ) {
	    ( $kind, $protocol, $port) = split /:/, $kind;
	    $port = "--dport $port";
	} else {
	    $port = '';
	    ( $kind, $protocol ) = split /:/ , $kind if $kind =~ /.*:.*/;
	}
	
	add_rule $inchainref,  "-p $protocol $source $port -j ACCEPT";
	add_rule $outchainref, "-p $protocol $dest $port -j ACCEPT";
    }
    
    sub setup_one_tunnel($$$$) {
	my ( $kind , $zone, $gateway, $gatewayzones ) = @_;
	
	fatal_error "Invalid zone ($zone) in tunnel \"$line\"" unless $zones{$zone}{type} eq 'ipv4';
	
	my $inchainref  = ensure_filter_chain "${zone}2${firewall_zone}", 1;
	my $outchainref = ensure_filter_chain "${firewall_zone}2${zone}", 1;
	
	my $source = match_source_net $gateway;
	my $dest   = match_dest_net   $gateway;
	
	my %tunneltypes = ( 'ipsec'         => { function => \&setup_one_ipsec ,         params   => [ $kind, $source, $dest , $gatewayzones ] } ,
			'ipsecnat'      => { function => \&setup_one_ipsec ,         params   => [ $kind, $source, $dest , $gatewayzones ] } ,
			'ipip'          => { function => \&setup_one_other,          params   => [ $source, $dest , 4 ] } ,
			'gre'           => { function => \&setup_one_other,          params   => [ $source, $dest , 47 ] } ,
			'6to4'          => { function => \&setup_one_other,          params   => [ $source, $dest , 41 ] } ,
			'pptpclient'    => { function => \&setup_pptp_client,        params   => [ $kind, $source, $dest ] } ,
			'pptpserver'    => { function => \&setup_pptp_server,        params   => [ $kind, $source, $dest ] } ,
			'openvpn'       => { function => \&setup_one_openvpn,        params   => [ $kind, $source, $dest ] } ,
			'openvpnclient' => { function => \&setup_one_openvpn_client, params   => [ $kind, $source, $dest ] } ,
			'openvpnserver' => { function => \&setup_one_openvpn_server, params   => [ $kind, $source, $dest ] } ,
			'generic'       => { function => \&setup_one_generic ,       params   => [ $kind, $source, $dest ] } ,
			);

	$kind = "\L$kind";

	(my $type) = split /:/, $kind;
	
	my $tunnelref = $tunneltypes{ $type };
	
	fatal_error "Tunnels of type $type are not supported: Tunnel \"$line\"" unless $tunnelref;
	
	$tunnelref->{function}->( $inchainref, $outchainref, @{$tunnelref->{params}} );
	
	progress_message "   Tunnel \"$line\" $done";
    }
    #
    # Setup_Tunnels() Starts Here
    #
    open TUNNELS, "$ENV{TMP_DIR}/tunnels" or fatal_error "Unable to open stripped tunnels file: $!";

    while ( $line = <TUNNELS> ) {

	chomp $line;
	$line =~ s/\s+/ /g;

	my ( $kind, $zone, $gateway, $gatewayzones, $extra ) = split /\s+/, $line;

	if ( $kind eq 'COMMENT' ) {
	    if ( $capabilities{COMMENTS} ) {
		( $comment = $line ) =~ s/^\s*COMMENT\s*//;
		$comment =~ s/\s*$//;
	    } else {
		warning_message "COMMENT ignored -- requires comment support in iptables/Netfilter";
	    }
	} else {
	    fatal_error "Invalid Tunnels file entry: \"$line\"" if $extra;
	    setup_one_tunnel $kind, $zone, $gateway, $gatewayzones;
	}
    }
	
    close TUNNELS;

    $comment = '';
}    

1;