package network::shorewall; # $Id$

use detect_devices;
use network::network;
use run_program;
use common;
use log;

my $shorewall_root = "/etc/shorewall";

sub check_iptables() {
    -f "$::prefix/etc/sysconfig/iptables" ||
    $::isStandalone && do {
	system('modprobe iptable_nat');
	-x '/sbin/iptables' && listlength(`/sbin/iptables -t nat -nL`) > 8;
    };
}

sub set_config_file {
    my ($file, @l) = @_;

    my $done;
    substInFile {
	if (!$done && (/^#LAST LINE/ || eof)) {
	    $_ = join('', map { join("\t", @$_) . "\n" } @l) . $_;
	    $done = 1;
	} else {
	    $_ = '' if /^[^#]/;
	}
    } "$::prefix${shorewall_root}/$file";
}

sub get_config_file {
    my ($file) = @_;
    map { [ split ' ' ] } grep { !/^#/ } cat_("$::prefix${shorewall_root}/$file");
}

sub dev_to_shorewall {
    my ($dev) = @_;
    $dev =~ /^ippp/ && "ippp+" ||
    $dev =~ /^ppp/ && "ppp+" ||
    $dev;
}

sub get_net_zone_interfaces {
    my ($net) = @_;
    #- read shorewall configuration first
    my @interfaces = map { $_->[1] } grep { $_->[0] eq 'net' } get_config_file('interfaces');
    #- else try to find the best interface available
    @interfaces ? @interfaces : dev_to_shorewall(network::tools::get_default_gateway_interface($net));
}

sub get_zones {
    my ($conf, $o_in) = @_;
    my $net = {};
    network::network::read_net_conf($net);
    #- find all interfaces but alias interfaces
    my @all_intf = grep { !/:/ } uniq(keys(%{$net->{ifcfg}}), detect_devices::get_net_interfaces());
    my %net_zone = map { $_ => undef } @all_intf;
    $net_zone{$_} = 1 foreach get_net_zone_interfaces($net);
    $o_in and $o_in->ask_from('', N("Please select the interfaces that will be protected by the firewall.

All interfaces directly connected to Internet should be selected,
while interfaces connected to a local network may be unselected.

Which interfaces should be protected?
"), [
        map {
            { text => network::tools::get_interface_description($net, $_), val => \$net_zone{$_}, type => 'bool' };
        } (sort keys %net_zone) ]);
    ($conf->{net_zone}, $conf->{loc_zone}) = partition { $net_zone{$_} } keys %net_zone;
}

sub add_interface_to_net_zone {
    my ($conf, $interface) = @_;
    if (!member($interface, @{$conf->{net_zone}})) {
        push @{$conf->{net_zone}}, $interface;
        @{$conf->{loc_zone}} = grep { $_ ne $interface } @{$conf->{loc_zone}};
    }
}

sub read {
    my ($o_in) = @_;
    #- read old rules file if config is not moved to rules.drakx yet
    my @rules = get_config_file(-f "$::prefix${shorewall_root}/rules.drakx" ? 'rules.drakx' : 'rules');
    my %conf = (disabled => !glob_("$::prefix/etc/rc3.d/S*shorewall"),
                ports => join(' ', map {
                    my $e = $_;
                    map { "$_/$e->[3]" } split(',', $e->[4]);
                } grep { $_->[0] eq 'ACCEPT' && $_->[1] eq 'net' } @rules),
               );
    $conf{redirects}{$_->[3]}{$_->[2]} = $_->[4] foreach grep { $_->[0] eq 'REDIRECT' } @rules;

    if (my ($e) = get_config_file('masq')) {
	($conf{masq}{net_interface}, $conf{masq}{subnet}) = @$e;
    }

    my @policy = get_config_file('policy');
    $conf{log_net_drop} = @policy ? (any { $_->[0] eq 'net' && $_->[1] eq 'all' && $_->[2] eq 'DROP' && $_->[3] } @policy) : 1;

    get_zones(\%conf, $o_in);
    $conf{net_zone}[0] && \%conf;
}

sub ports_by_proto {
    my ($ports) = @_;
    my %ports_by_proto;
    foreach (split ' ', $ports) {
	m!^(\d+(?::\d+)?)/(udp|tcp|icmp)$! or die "bad port $_\n";
	push @{$ports_by_proto{$2}}, $1;
    }
    \%ports_by_proto;
}

sub upgrade_to_shorewall3() {
    #- the 'FW' option has been removed from shorewall.conf as of shorewall 3.0
    my $ipsecfile_ok;
    substInFile {
        undef $_ if /^\s*FW=/;
        if ((/^\s*IPSECFILE=/ || eof) && !$ipsecfile_ok) {
            $ipsecfile_ok = 1;
            $_ = "IPSECFILE=zones\n";
        }
    } "$::prefix${shorewall_root}/shorewall.conf";
}

sub write {
    my ($conf, $o_in) = @_;
    my $use_pptp = any { /^ppp/ && cat_("$::prefix/etc/ppp/peers/$_") =~ /pptp/ } @{$conf->{net_zone}};
    my $ports_by_proto = ports_by_proto($conf->{ports});

    my ($include_drakx, $other_rules) = partition { $_ eq "INCLUDE\trules.drakx\n" } grep { !/^#/ } cat_("$::prefix${shorewall_root}/rules");
    #- warn if the config is already in rules.drakx and additionnal rules are configured
    if (!is_empty_array_ref($include_drakx) && !is_empty_array_ref($other_rules)) {
        my %actions = (
            keep => N("Keep custom rules"),
            drop => N("Drop custom rules"),
        );
        my $action = 'keep';
        !$o_in || $o_in->ask_from_(
            {
                messages => N("Your firewall configuration has been manually edited and contains
rules that may conflict with the configuration that has just been set up.
What do you want to do?"),
                title => N("Firewall"),
                icon => 'banner-security',
            },
            [ { val => \$action, type => 'list', list => [ 'keep', 'drop' ], format => sub { $actions{$_[0]} } } ]) or return;
        #- reset the rules files if the user has chosen to drop modifications
        undef $include_drakx if $action eq 'drop';
    }

    my $interface_settings = sub {
        my ($zone, $interface) = @_;
        [ $zone, $interface, 'detect', if_(detect_devices::is_bridge_interface($interface), 'routeback') ];
    };

    set_config_file("zones",
		    [ 'net', 'ipv4' ],
		    if_($conf->{loc_zone}[0], [ 'loc', 'ipv4' ]),
		    [ 'fw', 'firewall' ],
		   );
    set_config_file('interfaces',
                   (map { $interface_settings->('net', $_) } @{$conf->{net_zone}}),
                   (map { $interface_settings->('loc', $_) } @{$conf->{loc_zone} || []}),
		   );
    set_config_file('policy',
		    if_($conf->{loc_zone}[0], [ 'loc', 'net', 'ACCEPT' ], [ 'loc', 'fw', 'ACCEPT' ], [ 'fw', 'loc', 'ACCEPT' ]),
		    [ 'fw', 'net', 'ACCEPT' ],
		    [ 'net', 'all', 'DROP', if_($conf->{log_net_drop}, 'info') ],
		    [ 'all', 'all', 'REJECT', 'info' ],
		   );
    if (is_empty_array_ref($include_drakx)) {
        #- make sure the rules.drakx config is read, erasing user modifications
        set_config_file('rules', [ 'INCLUDE', 'rules.drakx' ]);
    }
    output_with_perm("$::prefix${shorewall_root}/" . 'rules.drakx', 0600, map { join("\t", @$_) . "\n" } (
    		    if_($use_pptp, [ 'ACCEPT', 'fw', 'loc:10.0.0.138', 'tcp', '1723' ]),
		    if_($use_pptp, [ 'ACCEPT', 'fw', 'loc:10.0.0.138', 'gre' ]),
		    (map_each { [ 'ACCEPT', 'net', 'fw', $::a, join(',', @$::b), '-' ] } %$ports_by_proto),
		    (map {
			map_each { [ 'REDIRECT', 'loc', $::a, $_, $::b, '-' ] } %{$conf->{redirects}{$_}};
		    } keys %{$conf->{redirects}}),
		   ));
    set_config_file('masq', if_(exists $conf->{masq}, [ $conf->{masq}{net_interface}, $conf->{masq}{subnet} ]));

    upgrade_to_shorewall3();

    require services;
    if ($conf->{disabled}) {
        services::disable('shorewall', $::isInstall);
        run_program::rooted($::prefix, '/sbin/shorewall', 'clear') unless $::isInstall;
    } else {
        services::enable('shorewall', $::isInstall);
    }
}

sub update_interfaces_list {
    my ($o_intf) = @_;
    $o_intf && member($o_intf, map { $_->[1] } get_config_file('interfaces')) and return;
    my $shorewall = network::shorewall::read();
    $shorewall && !$shorewall->{disabled} and network::shorewall::write($shorewall);
}

1;