2 ###############################################################################
4 # IPFire.org - A linux based firewall #
5 # Copyright (C) 2013 Alexander Marx <amarx@ipfire.org> #
7 # This program is free software: you can redistribute it and/or modify #
8 # it under the terms of the GNU General Public License as published by #
9 # the Free Software Foundation, either version 3 of the License, or #
10 # (at your option) any later version. #
12 # This program is distributed in the hope that it will be useful, #
13 # but WITHOUT ANY WARRANTY; without even the implied warranty of #
14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the #
15 # GNU General Public License for more details. #
17 # You should have received a copy of the GNU General Public License #
18 # along with this program. If not, see <http://www.gnu.org/licenses/>. #
20 ###############################################################################
24 require '/var/ipfire/general-functions.pl';
25 require "${General::swroot}/lang.pl";
26 require "/usr/lib/firewall/firewall-lib.pl";
28 # Set to one to enable debugging mode.
31 my $IPTABLES = "iptables --wait";
34 my $CHAIN_INPUT = "INPUTFW";
35 my $CHAIN_FORWARD = "FORWARDFW";
36 my $CHAIN_OUTPUT = "OUTGOINGFW";
37 my $CHAIN = $CHAIN_FORWARD;
38 my $CHAIN_NAT_SOURCE = "NAT_SOURCE";
39 my $CHAIN_NAT_DESTINATION = "NAT_DESTINATION";
40 my $CHAIN_MANGLE_NAT_DESTINATION_FIX = "NAT_DESTINATION";
41 my @VALID_CHAINS = ($CHAIN_INPUT, $CHAIN_FORWARD, $CHAIN_OUTPUT);
42 my @ANY_ADDRESSES = ("0.0.0.0/0.0.0.0", "0.0.0.0/0", "0/0");
44 my @PROTOCOLS = ("tcp", "udp", "icmp", "igmp", "ah", "esp", "gre", "ipv6", "ipip");
45 my @PROTOCOLS_WITH_PORTS = ("tcp", "udp");
47 my @VALID_TARGETS = ("ACCEPT", "DROP", "REJECT");
51 my %defaultNetworks=();
55 my %configoutgoingfw=();
59 my $configfwdfw = "${General::swroot}/firewall/config";
60 my $configinput = "${General::swroot}/firewall/input";
61 my $configoutgoing = "${General::swroot}/firewall/outgoing";
62 my $p2pfile = "${General::swroot}/firewall/p2protocols";
63 my $configgrp = "${General::swroot}/fwhosts/customgroups";
64 my $netsettings = "${General::swroot}/ethernet/settings";
66 &General
::readhash
("${General::swroot}/firewall/settings", \
%fwdfwsettings);
67 &General
::readhash
("${General::swroot}/optionsfw/settings", \
%fwoptions);
68 &General
::readhash
("$netsettings", \
%defaultNetworks);
69 &General
::readhasharray
($configfwdfw, \
%configfwdfw);
70 &General
::readhasharray
($configinput, \
%configinputfw);
71 &General
::readhasharray
($configoutgoing, \
%configoutgoingfw);
72 &General
::readhasharray
($configgrp, \
%customgrp);
74 my @log_limit_options = &make_log_limit_options
();
76 my $POLICY_INPUT_ALLOWED = 0;
77 my $POLICY_FORWARD_ALLOWED = ($fwdfwsettings{"POLICY"} eq "MODE2");
78 my $POLICY_OUTPUT_ALLOWED = ($fwdfwsettings{"POLICY1"} eq "MODE2");
80 my $POLICY_INPUT_ACTION = $fwoptions{"FWPOLICY2"};
81 my $POLICY_FORWARD_ACTION = $fwoptions{"FWPOLICY"};
82 my $POLICY_OUTPUT_ACTION = $fwoptions{"FWPOLICY1"};
91 # Reload firewall rules.
94 # Load P2P block rules.
97 # Reload firewall policy.
98 run
("/usr/sbin/firewall-policy");
102 # Executes or prints the given shell command.
111 print_error
("ERROR: $command");
119 print STDERR
"$message\n";
129 printf(" %2d: %s", $i++, $_);
137 return scalar @
$hash;
141 run
("$IPTABLES -F $CHAIN_INPUT");
142 run
("$IPTABLES -F $CHAIN_FORWARD");
143 run
("$IPTABLES -F $CHAIN_OUTPUT");
144 run
("$IPTABLES -t nat -F $CHAIN_NAT_SOURCE");
145 run
("$IPTABLES -t nat -F $CHAIN_NAT_DESTINATION");
146 run
("$IPTABLES -t mangle -F $CHAIN_MANGLE_NAT_DESTINATION_FIX");
150 if (! -z
"${General::swroot}/firewall/input"){
151 &buildrules
(\
%configinputfw);
153 if (! -z
"${General::swroot}/firewall/outgoing"){
154 &buildrules
(\
%configoutgoingfw);
156 if (! -z
"${General::swroot}/firewall/config"){
157 &buildrules
(\
%configfwdfw);
164 # Search for targets that need to be specially handled when adding
165 # forwarding rules. Additional rules will automatically get inserted
166 # into the INPUT/OUTPUT chains for these targets.
167 my @special_input_targets = ();
168 if (!$POLICY_FORWARD_ALLOWED) {
169 push(@special_input_targets, "ACCEPT");
172 if ($POLICY_INPUT_ACTION eq "DROP") {
173 push(@special_input_targets, "REJECT");
174 } elsif ($POLICY_INPUT_ACTION eq "REJECT") {
175 push(@special_input_targets, "DROP");
178 my @special_output_targets = ();
179 if ($POLICY_OUTPUT_ALLOWED) {
180 push(@special_output_targets, ("DROP", "REJECT"));
182 push(@special_output_targets, "ACCEPT");
184 if ($POLICY_OUTPUT_ACTION eq "DROP") {
185 push(@special_output_targets, "REJECT");
186 } elsif ($POLICY_OUTPUT_ACTION eq "REJECT") {
187 push(@special_output_targets, "DROP");
191 foreach my $key (sort {$a <=> $b} keys %$hash) {
192 # Skip disabled rules.
193 next unless ($$hash{$key}[2] eq 'ON');
195 # Count number of elements in this line
196 my $elements = &count_elements
($$hash{$key});
199 print_rule
($$hash{$key});
202 # Check if the target is valid.
203 my $target = $$hash{$key}[0];
204 if (!$target ~~ @VALID_TARGETS) {
205 print_error
("Invalid target '$target' for rule $key");
209 # Check if the chain is valid.
210 my $chain = $$hash{$key}[1];
211 if (!$chain ~~ @VALID_CHAINS) {
212 print_error
("Invalid chain '$chain' in rule $key");
216 # Collect all sources.
217 my @sources = &fwlib
::get_addresses
($hash, $key, "src");
219 # Collect all destinations.
220 my @destinations = &fwlib
::get_addresses
($hash, $key, "tgt");
222 # True if the destination is the firewall itself.
223 my $destination_is_firewall = ($$hash{$key}[5] eq "ipfire");
225 # Check if logging should be enabled.
226 my $LOG = ($$hash{$key}[17] eq 'ON');
228 # Check if NAT is enabled and initialize variables, that we use for that.
229 my $NAT = ($$hash{$key}[28] eq 'ON');
232 $NAT_MODE = uc($$hash{$key}[31]);
235 # Set up time constraints.
236 my @time_options = ();
237 if ($$hash{$key}[18] eq 'ON') {
238 push(@time_options, ("-m", "time"));
240 # Select all days of the week this match is active.
242 if ($$hash{$key}[19] ne '') {
243 push (@weekdays, "Mon");
245 if ($$hash{$key}[20] ne '') {
246 push (@weekdays, "Tue");
248 if ($$hash{$key}[21] ne '') {
249 push (@weekdays, "Wed");
251 if ($$hash{$key}[22] ne '') {
252 push (@weekdays, "Thu");
254 if ($$hash{$key}[23] ne '') {
255 push (@weekdays, "Fri");
257 if ($$hash{$key}[24] ne '') {
258 push (@weekdays, "Sat");
260 if ($$hash{$key}[25] ne '') {
261 push (@weekdays, "Sun");
264 push(@time_options, ("--weekdays", join(",", @weekdays)));
267 # Convert start time.
268 my $time_start = &format_time
($$hash{$key}[26]);
270 push(@time_options, ("--timestart", $time_start));
274 my $time_stop = &format_time
($$hash{$key}[27]);
276 push(@time_options, ("--timestop", $time_stop));
280 # Concurrent connection limit
281 my @ratelimit_options = ();
283 if (($elements ge 34) && ($$hash{$key}[32] eq 'ON')) {
284 my $conn_limit = $$hash{$key}[33];
286 if ($conn_limit ge 1) {
287 push(@ratelimit_options, ("-m", "connlimit"));
289 # Use the the entire source IP address
290 push(@ratelimit_options, "--connlimit-saddr");
291 push(@ratelimit_options, ("--connlimit-mask", "32"));
294 push(@ratelimit_options, ("--connlimit-upto", $conn_limit));
299 if (($elements ge 37) && ($$hash{$key}[34] eq 'ON')) {
300 my $rate_limit = "$$hash{$key}[35]/$$hash{$key}[36]";
303 push(@ratelimit_options, ("-m", "limit"));
304 push(@ratelimit_options, ("--limit", $rate_limit));
308 # Check which protocols are used in this rule and so that we can
309 # later group rules by protocols.
310 my @protocols = &get_protocols
($hash, $key);
312 print_error
("Invalid protocol configuration for rule $key");
316 foreach my $protocol (@protocols) {
317 # Check if the given protocol is supported.
318 if (($protocol ne "all") && (!$protocol ~~ @PROTOCOLS)) {
319 print_error
("Protocol $protocol is not supported (rule $key)");
323 # Prepare protocol options (like ICMP types, ports, etc...).
324 my @protocol_options = &get_protocol_options
($hash, $key, $protocol, 0);
326 # Check if this protocol knows ports.
327 my $protocol_has_ports = ($protocol ~~ @PROTOCOLS_WITH_PORTS);
329 foreach my $src (@sources) {
330 # Skip invalid source.
331 next unless (defined $src);
335 my $source = @
$src[0];
336 if ($source ~~ @ANY_ADDRESSES) {
340 my $source_intf = @
$src[1];
342 foreach my $dst (@destinations) {
343 # Skip invalid rules.
344 next unless (defined $dst);
345 next if (!$dst || ($dst eq "none"));
347 # Sanitize destination.
348 my $destination = @
$dst[0];
349 if ($destination ~~ @ANY_ADDRESSES) {
353 my $destination_intf = @
$dst[1];
355 # Array with iptables arguments.
359 if ($protocol ne "all") {
360 push(@options, @protocol_options);
363 # Prepare source options.
364 my @source_options = ();
365 if ($source =~ /mac/) {
366 push(@source_options, $source);
368 push(@source_options, ("-s", $source));
371 # Prepare destination options.
372 my @destination_options = ();
374 push(@destination_options, ("-d", $destination));
377 # Add time constraint options.
378 push(@options, @time_options);
380 # Add ratelimiting option
381 push(@options, @ratelimit_options);
383 my $firewall_is_in_source_subnet = 1;
385 $firewall_is_in_source_subnet = &firewall_is_in_subnet
($source);
388 my $firewall_is_in_destination_subnet = 1;
390 $firewall_is_in_destination_subnet = &firewall_is_in_subnet
($destination);
395 my $nat_address = &fwlib
::get_nat_address
($$hash{$key}[29], $source);
397 # Skip NAT rules if the NAT address is unknown
398 # (i.e. no internet connection has been established, yet).
399 next unless ($nat_address);
402 if ($NAT_MODE eq "DNAT") {
403 my @nat_options = ();
404 if ($protocol ne "all") {
405 my @nat_protocol_options = &get_protocol_options
($hash, $key, $protocol, 1);
406 push(@nat_options, @nat_protocol_options);
408 push(@nat_options, @time_options);
410 # Make port-forwardings useable from the internal networks.
411 my @internal_addresses = &fwlib
::get_internal_firewall_ip_addresses
(1);
412 unless ($nat_address ~~ @internal_addresses) {
413 &add_dnat_mangle_rules
($nat_address, $source_intf, @nat_options);
416 push(@nat_options, @source_options);
417 push(@nat_options, ("-d", $nat_address));
420 if ($protocol_has_ports) {
421 $dnat_port = &get_dnat_target_port
($hash, $key);
424 my @nat_action_options = ();
426 # Use iptables REDIRECT
427 my $use_redirect = ($destination_is_firewall && !$destination && $protocol_has_ports && $dnat_port);
429 push(@nat_action_options, ("-j", "REDIRECT", "--to-ports", $dnat_port));
433 if ($destination_is_firewall && !$destination) {
434 $destination = &fwlib
::get_external_address
();
436 next unless ($destination);
438 my ($dnat_address, $dnat_mask) = split("/", $destination);
439 @destination_options = ("-d", $dnat_address);
441 if ($protocol_has_ports) {
442 my $dnat_port = &get_dnat_target_port
($hash, $key);
445 $dnat_address .= ":$dnat_port";
449 push(@nat_action_options, ("-j", "DNAT", "--to-destination", $dnat_address));
453 run
("$IPTABLES -t nat -A $CHAIN_NAT_DESTINATION @nat_options @log_limit_options -j LOG --log-prefix 'DNAT '");
455 run
("$IPTABLES -t nat -A $CHAIN_NAT_DESTINATION @nat_options @nat_action_options");
458 } elsif ($NAT_MODE eq "SNAT") {
459 my @nat_options = @options;
461 push(@nat_options, @source_options);
462 push(@nat_options, @destination_options);
465 run
("$IPTABLES -t nat -A $CHAIN_NAT_SOURCE @nat_options @log_limit_options -j LOG --log-prefix 'SNAT '");
467 run
("$IPTABLES -t nat -A $CHAIN_NAT_SOURCE @nat_options -j SNAT --to-source $nat_address");
471 # Add source and destination interface to the filter rules.
472 # These are supposed to help filtering forged packets that originate
473 # from BLUE with an IP address from GREEN for instance.
475 push(@source_options, ("-i", $source_intf));
478 if ($destination_intf) {
479 push(@destination_options, ("-o", $destination_intf));
482 push(@options, @source_options);
483 push(@options, @destination_options);
485 # Insert firewall rule.
487 run
("$IPTABLES -A $chain @options @log_limit_options -j LOG --log-prefix '$chain '");
489 run
("$IPTABLES -A $chain @options -j $target");
491 # Handle forwarding rules and add corresponding rules for firewall access.
492 if ($chain eq $CHAIN_FORWARD) {
493 # If the firewall is part of the destination subnet and access to the destination network
494 # is granted/forbidden for any network that the firewall itself is part of, we grant/forbid access
495 # for the firewall, too.
496 if ($firewall_is_in_destination_subnet && ($target ~~ @special_input_targets)) {
498 run
("$IPTABLES -A $CHAIN_INPUT @options @log_limit_options -j LOG --log-prefix '$CHAIN_INPUT '");
500 run
("$IPTABLES -A $CHAIN_INPUT @options -j $target");
504 if ($firewall_is_in_source_subnet && ($target ~~ @special_output_targets)) {
506 run
("$IPTABLES -A $CHAIN_OUTPUT @options @log_limit_options -j LOG --log-prefix '$CHAIN_OUTPUT '");
508 run
("$IPTABLES -A $CHAIN_OUTPUT @options -j $target");
515 #Reload firewall.local if present
516 if ( -f
'/etc/sysconfig/firewall.local'){
517 run
("/etc/sysconfig/firewall.local reload");
521 # Formats the given timestamp into the iptables format which is "hh:mm" UTC.
525 # Convert the given time into minutes.
526 my $minutes = &time_convert_to_minutes
($val);
528 # Move the timestamp into UTC.
529 $minutes += &time_utc_offset
();
531 # Make sure $minutes is between 00:00 and 23:59.
536 if ($minutes > 1440) {
541 return sprintf("%02d:%02d", $minutes / 60, $minutes % 60);
544 # Calculates the offsets in minutes from the local timezone to UTC.
545 sub time_utc_offset
{
546 my @localtime = localtime(time);
547 my @gmtime = gmtime(time);
549 return ($gmtime[2] * 60 + $gmtime[1] % 60) - ($localtime[2] * 60 + $localtime[1] % 60);
552 # Takes a timestamp like "14:00" and converts it into minutes since midnight.
553 sub time_convert_to_minutes
{
554 my ($hrs, $min) = split(":", shift);
556 return ($hrs * 60) + $min;
560 open(FILE
, "<$p2pfile") or die "Unable to read $p2pfile";
562 foreach my $p2pentry (<FILE
>) {
563 my @p2pline = split(/\;/, $p2pentry);
564 next unless ($p2pline[2] eq "off");
566 push(@protocols, "--$p2pline[1]");
570 run
("$IPTABLES -F P2PBLOCK");
572 run
("$IPTABLES -A P2PBLOCK -m ipp2p @protocols -j DROP");
580 my $uses_source_ports = ($$hash{$key}[7] eq "ON");
581 my $uses_services = ($$hash{$key}[11] eq "ON");
585 # Rules which don't have source ports or services (like ICMP, ESP, ...).
586 if (!$uses_source_ports && !$uses_services) {
587 push(@protocols, $$hash{$key}[8]);
589 # Rules which either use ports or services.
590 } elsif ($uses_source_ports || $uses_services) {
591 # Check if service group or service
592 if ($$hash{$key}[14] eq 'cust_srv') {
593 push(@protocols, &fwlib
::get_srv_prot
($$hash{$key}[15]));
595 } elsif($$hash{$key}[14] eq 'cust_srvgrp'){
596 my $protos = &fwlib
::get_srvgrp_prot
($$hash{$key}[15]);
597 push(@protocols, split(",", $protos));
600 # Fetch the protocol for this rule.
601 my $protocol = lc($$hash{$key}[8]);
603 # Fetch source and destination ports for this rule.
604 my $source_ports = $$hash{$key}[10];
605 my $destination_ports = $$hash{$key}[15];
607 # Check if ports are set for protocols which do not support ports.
608 if (!($protocol ~~ @PROTOCOLS_WITH_PORTS) && ($source_ports || $destination_ports)) {
609 print_error
("$protocol does not support ports");
613 push(@protocols, $protocol);
617 # Remove all empty elements
618 @protocols = map { $_ ?
$_ : () } @protocols;
620 # If no protocol has been defined, we assume "all".
622 push(@protocols, "all");
625 # Make all protocol names lowercase.
626 @protocols = map { lc } @protocols;
631 sub get_protocol_options
{
634 my $protocol = shift;
635 my $nat_options_wanted = shift;
638 # Nothing to do if no protocol is specified.
639 if ($protocol eq "all") {
642 push(@options, ("-p", $protocol));
645 if ($protocol ~~ @PROTOCOLS_WITH_PORTS) {
646 # Process source ports.
647 my $use_src_ports = ($$hash{$key}[7] eq "ON");
648 my $src_ports = $$hash{$key}[10];
650 if ($use_src_ports && $src_ports) {
651 push(@options, &format_ports
($src_ports, "src"));
654 # Process destination ports.
655 my $use_dst_ports = ($$hash{$key}[11] eq "ON");
656 my $use_dnat = (($$hash{$key}[28] eq "ON") && ($$hash{$key}[31] eq "dnat"));
658 if ($use_dst_ports) {
659 my $dst_ports_mode = $$hash{$key}[14];
660 my $dst_ports = $$hash{$key}[15];
662 if (($dst_ports_mode eq "TGT_PORT") && $dst_ports) {
663 if ($nat_options_wanted && $use_dnat && $$hash{$key}[30]) {
664 $dst_ports = $$hash{$key}[30];
666 push(@options, &format_ports
($dst_ports, "dst"));
668 } elsif ($dst_ports_mode eq "cust_srv") {
669 if ($protocol eq "ICMP") {
670 push(@options, ("--icmp-type", &fwlib
::get_srv_port
($dst_ports, 3, "ICMP")));
672 $dst_ports = &fwlib
::get_srv_port
($dst_ports, 1, uc($protocol));
673 push(@options, &format_ports
($dst_ports, "dst"));
676 } elsif ($dst_ports_mode eq "cust_srvgrp") {
677 push(@options, &fwlib
::get_srvgrp_port
($dst_ports, uc($protocol)));
682 # Check if a single ICMP type is selected.
683 if ($protocol eq "icmp") {
684 my $icmp_type = $$hash{$key}[9];
686 if (($icmp_type ne "All ICMP-Types") && $icmp_type) {
687 push(@options, ("--icmp-type", $icmp_type));
699 if ($type eq "src") {
701 } elsif ($type eq "dst") {
707 if ($ports =~ /\|/) {
709 push(@options, ("-m", "multiport"));
713 push(@options, ($arg, $ports));
719 sub get_dnat_target_port
{
723 if ($$hash{$key}[14] eq "TGT_PORT") {
724 my $port = $$hash{$key}[15];
725 my $external_port = $$hash{$key}[30];
727 if ($external_port && ($port ne $external_port)) {
728 return $$hash{$key}[15];
733 sub add_dnat_mangle_rules
{
734 my $nat_address = shift;
735 my $interface = shift;
739 foreach my $zone ("GREEN", "BLUE", "ORANGE") {
742 # Skip rule if not all required information exists.
743 next unless (exists $defaultNetworks{$zone . "_NETADDRESS"});
744 next unless (exists $defaultNetworks{$zone . "_NETMASK"});
746 next if ($interface && $interface ne $defaultNetworks{$zone . "_DEV"});
748 my @mangle_options = @options;
750 my $netaddress = $defaultNetworks{$zone . "_NETADDRESS"};
751 $netaddress .= "/" . $defaultNetworks{$zone . "_NETMASK"};
753 push(@mangle_options, ("-s", $netaddress, "-d", $nat_address));
754 push(@mangle_options, ("-j", "MARK", "--set-mark", $mark));
756 run
("$IPTABLES -t mangle -A $CHAIN_MANGLE_NAT_DESTINATION_FIX @mangle_options");
760 sub make_log_limit_options
{
761 my @options = ("-m", "limit");
763 # Maybe we should get this from the configuration.
766 # We limit log messages to $limit messages per minute.
767 push(@options, ("--limit", "$limit/min"));
769 # And we allow bursts of 2x $limit.
770 push(@options, ("--limit-burst", $limit * 2));
775 sub firewall_is_in_subnet
{
778 # ORANGE is missing here, because nothing may ever access
779 # the firewall from this network.
780 my $address = &fwlib
::get_internal_firewall_ip_address
($subnet, 0);