config/firewall/rules.pl

   1 #!/usr/bin/perl -w
   2 ###############################################################################
   3 #                                                                             #
   4 # IPFire.org - A linux based firewall                                         #
   5 # Copyright (C) 2013 Alexander Marx <amarx@ipfire.org>                        #
   6 #                                                                             #
   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.                                         #
  11 #                                                                             #
  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.                                #
  16 #                                                                             #
  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/>.       #
  19 #                                                                             #
  20 ###############################################################################
  21
  22 use strict;
  23
  24 require '/var/ipfire/general-functions.pl';
  25 require "${General::swroot}/lang.pl";
  26 require "/usr/lib/firewall/firewall-lib.pl";
  27
  28 # Set to one to enable debugging mode.
  29 my $DEBUG = 0;
  30
  31 my $IPTABLES = "iptables --wait";
  32
  33 # iptables chains
  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");
  43
  44 my @PROTOCOLS = ("tcp", "udp", "icmp", "igmp", "ah", "esp", "gre", "ipv6", "ipip");
  45 my @PROTOCOLS_WITH_PORTS = ("tcp", "udp");
  46
  47 my @VALID_TARGETS = ("ACCEPT", "DROP", "REJECT");
  48
  49 my %fwdfwsettings=();
  50 my %fwoptions = ();
  51 my %defaultNetworks=();
  52 my %configfwdfw=();;
  53 my %customgrp=();
  54 my %configinputfw=();
  55 my %configoutgoingfw=();
  56 my %confignatfw=();
  57 my @p2ps=();
  58
  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";
  65
  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);
  73
  74 my @log_limit_options = &make_log_limit_options();
  75
  76 my $POLICY_INPUT_ALLOWED   = 0;
  77 my $POLICY_FORWARD_ALLOWED = ($fwdfwsettings{"POLICY"} eq "MODE2");
  78 my $POLICY_OUTPUT_ALLOWED  = ($fwdfwsettings{"POLICY1"} eq "MODE2");
  79
  80 my $POLICY_INPUT_ACTION    = $fwoptions{"FWPOLICY2"};
  81 my $POLICY_FORWARD_ACTION  = $fwoptions{"FWPOLICY"};
  82 my $POLICY_OUTPUT_ACTION   = $fwoptions{"FWPOLICY1"};
  83
  84 # MAIN
  85 &main();
  86
  87 sub main {
  88         # Flush all chains.
  89         &flush();
  90
  91         # Reload firewall rules.
  92         &preparerules();
  93
  94         # Load P2P block rules.
  95         &p2pblock();
  96
  97         # Reload firewall policy.
  98         run("/usr/sbin/firewall-policy");
  99 }
 100
 101 sub run {
 102         # Executes or prints the given shell command.
 103         my $command = shift;
 104
 105         if ($DEBUG) {
 106                 print "$command\n";
 107         } else {
 108                 system "$command";
 109
 110                 if ($?) {
 111                         print_error("ERROR: $command");
 112                 }
 113         }
 114 }
 115
 116 sub print_error {
 117         my $message = shift;
 118
 119         print STDERR "$message\n";
 120 }
 121
 122 sub print_rule {
 123         my $hash = shift;
 124
 125         print "\nRULE:";
 126
 127         my $i = 0;
 128         foreach (@$hash) {
 129                 printf("  %2d: %s", $i++, $_);
 130         }
 131         print "\n";
 132 }
 133
 134 sub flush {
 135         run("$IPTABLES -F $CHAIN_INPUT");
 136         run("$IPTABLES -F $CHAIN_FORWARD");
 137         run("$IPTABLES -F $CHAIN_OUTPUT");
 138         run("$IPTABLES -t nat -F $CHAIN_NAT_SOURCE");
 139         run("$IPTABLES -t nat -F $CHAIN_NAT_DESTINATION");
 140         run("$IPTABLES -t mangle -F $CHAIN_MANGLE_NAT_DESTINATION_FIX");
 141 }
 142
 143 sub preparerules {
 144         if (! -z  "${General::swroot}/firewall/input"){
 145                 &buildrules(\%configinputfw);
 146         }
 147         if (! -z  "${General::swroot}/firewall/outgoing"){
 148                 &buildrules(\%configoutgoingfw);
 149         }
 150         if (! -z  "${General::swroot}/firewall/config"){
 151                 &buildrules(\%configfwdfw);
 152         }
 153 }
 154
 155 sub buildrules {
 156         my $hash = shift;
 157
 158         # Search for targets that need to be specially handled when adding
 159         # forwarding rules. Additional rules will automatically get inserted
 160         # into the INPUT/OUTPUT chains for these targets.
 161         my @special_input_targets = ();
 162         if (!$POLICY_FORWARD_ALLOWED) {
 163                 push(@special_input_targets, "ACCEPT");
 164         }
 165
 166         if ($POLICY_INPUT_ACTION eq "DROP") {
 167                 push(@special_input_targets, "REJECT");
 168         } elsif ($POLICY_INPUT_ACTION eq "REJECT") {
 169                 push(@special_input_targets, "DROP");
 170         }
 171
 172         my @special_output_targets = ();
 173         if ($POLICY_OUTPUT_ALLOWED) {
 174                 push(@special_output_targets, ("DROP", "REJECT"));
 175         } else {
 176                 push(@special_output_targets, "ACCEPT");
 177
 178                 if ($POLICY_OUTPUT_ACTION eq "DROP") {
 179                         push(@special_output_targets, "REJECT");
 180                 } elsif ($POLICY_OUTPUT_ACTION eq "REJECT") {
 181                         push(@special_output_targets, "DROP");
 182                 }
 183         }
 184
 185         foreach my $key (sort {$a <=> $b} keys %$hash) {
 186                 # Skip disabled rules.
 187                 next unless ($$hash{$key}[2] eq 'ON');
 188
 189                 if ($DEBUG) {
 190                         print_rule($$hash{$key});
 191                 }
 192
 193                 # Check if the target is valid.
 194                 my $target = $$hash{$key}[0];
 195                 if (!$target ~~ @VALID_TARGETS) {
 196                         print_error("Invalid target '$target' for rule $key");
 197                         next;
 198                 }
 199
 200                 # Check if the chain is valid.
 201                 my $chain = $$hash{$key}[1];
 202                 if (!$chain ~~ @VALID_CHAINS) {
 203                         print_error("Invalid chain '$chain' in rule $key");
 204                         next;
 205                 }
 206
 207                 # Collect all sources.
 208                 my @sources = &fwlib::get_addresses($hash, $key, "src");
 209
 210                 # Collect all destinations.
 211                 my @destinations = &fwlib::get_addresses($hash, $key, "tgt");
 212
 213                 # True if the destination is the firewall itself.
 214                 my $destination_is_firewall = ($$hash{$key}[5] eq "ipfire");
 215
 216                 # Check if logging should be enabled.
 217                 my $LOG = ($$hash{$key}[17] eq 'ON');
 218
 219                 # Check if NAT is enabled and initialize variables, that we use for that.
 220                 my $NAT = ($$hash{$key}[28] eq 'ON');
 221                 my $NAT_MODE;
 222                 if ($NAT) {
 223                         $NAT_MODE = uc($$hash{$key}[31]);
 224                 }
 225
 226                 # Set up time constraints.
 227                 my @time_options = ();
 228                 if ($$hash{$key}[18] eq 'ON') {
 229                         push(@time_options, ("-m", "time"));
 230
 231                         # Select all days of the week this match is active.
 232                         my @weekdays = ();
 233                         if ($$hash{$key}[19] ne '') {
 234                                 push (@weekdays, "Mon");
 235                         }
 236                         if ($$hash{$key}[20] ne '') {
 237                                 push (@weekdays, "Tue");
 238                         }
 239                         if ($$hash{$key}[21] ne '') {
 240                                 push (@weekdays, "Wed");
 241                         }
 242                         if ($$hash{$key}[22] ne '') {
 243                                 push (@weekdays, "Thu");
 244                         }
 245                         if ($$hash{$key}[23] ne '') {
 246                                 push (@weekdays, "Fri");
 247                         }
 248                         if ($$hash{$key}[24] ne '') {
 249                                 push (@weekdays, "Sat");
 250                         }
 251                         if ($$hash{$key}[25] ne '') {
 252                                 push (@weekdays, "Sun");
 253                         }
 254                         if (@weekdays) {
 255                                 push(@time_options, ("--weekdays", join(",", @weekdays)));
 256                         }
 257
 258                         # Convert start time.
 259                         my $time_start = &format_time($$hash{$key}[26]);
 260                         if ($time_start) {
 261                                 push(@time_options, ("--timestart", $time_start));
 262                         }
 263
 264                         # Convert end time.
 265                         my $time_stop = &format_time($$hash{$key}[27]);
 266                         if ($time_stop) {
 267                                 push(@time_options, ("--timestop", $time_stop));
 268                         }
 269                 }
 270
 271                 # Check which protocols are used in this rule and so that we can
 272                 # later group rules by protocols.
 273                 my @protocols = &get_protocols($hash, $key);
 274                 if (!@protocols) {
 275                         print_error("Invalid protocol configuration for rule $key");
 276                         next;
 277                 }
 278
 279                 foreach my $protocol (@protocols) {
 280                         # Check if the given protocol is supported.
 281                         if (($protocol ne "all") && (!$protocol ~~ @PROTOCOLS)) {
 282                                 print_error("Protocol $protocol is not supported (rule $key)");
 283                                 next;
 284                         }
 285
 286                         # Prepare protocol options (like ICMP types, ports, etc...).
 287                         my @protocol_options = &get_protocol_options($hash, $key, $protocol, 0);
 288
 289                         # Check if this protocol knows ports.
 290                         my $protocol_has_ports = ($protocol ~~ @PROTOCOLS_WITH_PORTS);
 291
 292                         foreach my $src (@sources) {
 293                                 # Skip invalid source.
 294                                 next unless (defined $src);
 295                                 next unless ($src);
 296
 297                                 # Sanitize source.
 298                                 my $source = @$src[0];
 299                                 if ($source ~~ @ANY_ADDRESSES) {
 300                                         $source = "";
 301                                 }
 302
 303                                 my $source_intf = @$src[1];
 304
 305                                 foreach my $dst (@destinations) {
 306                                         # Skip invalid rules.
 307                                         next unless (defined $dst);
 308                                         next if (!$dst || ($dst eq "none"));
 309
 310                                         # Sanitize destination.
 311                                         my $destination = @$dst[0];
 312                                         if ($destination ~~ @ANY_ADDRESSES) {
 313                                                 $destination = "";
 314                                         }
 315
 316                                         my $destination_intf = @$dst[1];
 317
 318                                         # Array with iptables arguments.
 319                                         my @options = ();
 320
 321                                         # Append protocol.
 322                                         if ($protocol ne "all") {
 323                                                 push(@options, @protocol_options);
 324                                         }
 325
 326                                         # Prepare source options.
 327                                         my @source_options = ();
 328                                         if ($source =~ /mac/) {
 329                                                 push(@source_options, $source);
 330                                         } elsif ($source) {
 331                                                 push(@source_options, ("-s", $source));
 332                                         }
 333
 334                                         if ($source_intf) {
 335                                                 push(@source_options, ("-i", $source_intf));
 336                                         }
 337
 338                                         # Prepare destination options.
 339                                         my @destination_options = ();
 340                                         if ($destination) {
 341                                                 push(@destination_options, ("-d", $destination));
 342                                         }
 343
 344                                         if ($destination_intf) {
 345                                                 push(@destination_options, ("-o", $destination_intf));
 346                                         }
 347
 348                                         # Add time constraint options.
 349                                         push(@options, @time_options);
 350
 351                                         my $firewall_is_in_source_subnet = 1;
 352                                         if ($source) {
 353                                                 $firewall_is_in_source_subnet = &firewall_is_in_subnet($source);
 354                                         }
 355
 356                                         my $firewall_is_in_destination_subnet = 1;
 357                                         if ($destination) {
 358                                                 $firewall_is_in_destination_subnet = &firewall_is_in_subnet($destination);
 359                                         }
 360
 361                                         # Process NAT rules.
 362                                         if ($NAT) {
 363                                                 my $nat_address = &fwlib::get_nat_address($$hash{$key}[29], $source);
 364
 365                                                 # Skip NAT rules if the NAT address is unknown
 366                                                 # (i.e. no internet connection has been established, yet).
 367                                                 next unless ($nat_address);
 368
 369                                                 # Destination NAT
 370                                                 if ($NAT_MODE eq "DNAT") {
 371                                                         my @nat_options = ();
 372                                                         if ($protocol ne "all") {
 373                                                                 my @nat_protocol_options = &get_protocol_options($hash, $key, $protocol, 1);
 374                                                                 push(@nat_options, @nat_protocol_options);
 375                                                         }
 376                                                         push(@nat_options, @time_options);
 377
 378                                                         # Make port-forwardings useable from the internal networks.
 379                                                         my @internal_addresses = &fwlib::get_internal_firewall_ip_addresses(1);
 380                                                         unless ($nat_address ~~ @internal_addresses) {
 381                                                                 &add_dnat_mangle_rules($nat_address, $source_intf, @nat_options);
 382                                                         }
 383
 384                                                         push(@nat_options, @source_options);
 385                                                         push(@nat_options, ("-d", $nat_address));
 386
 387                                                         my $dnat_port;
 388                                                         if ($protocol_has_ports) {
 389                                                                 $dnat_port = &get_dnat_target_port($hash, $key);
 390                                                         }
 391
 392                                                         my @nat_action_options = ();
 393
 394                                                         # Use iptables REDIRECT
 395                                                         my $use_redirect = ($destination_is_firewall && !$destination && $protocol_has_ports && $dnat_port);
 396                                                         if ($use_redirect) {
 397                                                                 push(@nat_action_options, ("-j", "REDIRECT", "--to-ports", $dnat_port));
 398
 399                                                         # Use iptables DNAT
 400                                                         } else {
 401                                                                 if ($destination_is_firewall && !$destination) {
 402                                                                         $destination = &fwlib::get_external_address();
 403                                                                 }
 404                                                                 next unless ($destination);
 405
 406                                                                 my ($dnat_address, $dnat_mask) = split("/", $destination);
 407                                                                 @destination_options = ("-d", $dnat_address);
 408
 409                                                                 if ($protocol_has_ports) {
 410                                                                         my $dnat_port = &get_dnat_target_port($hash, $key);
 411
 412                                                                         if ($dnat_port) {
 413                                                                                 $dnat_address .= ":$dnat_port";
 414                                                                         }
 415                                                                 }
 416
 417                                                                 push(@nat_action_options, ("-j", "DNAT", "--to-destination", $dnat_address));
 418                                                         }
 419
 420                                                         if ($LOG) {
 421                                                                 run("$IPTABLES -t nat -A $CHAIN_NAT_DESTINATION @nat_options @log_limit_options -j LOG --log-prefix 'DNAT '");
 422                                                         }
 423                                                         run("$IPTABLES -t nat -A $CHAIN_NAT_DESTINATION @nat_options @nat_action_options");
 424
 425                                                 # Source NAT
 426                                                 } elsif ($NAT_MODE eq "SNAT") {
 427                                                         my @nat_options = @options;
 428
 429                                                         push(@nat_options, @source_options);
 430                                                         push(@nat_options, @destination_options);
 431
 432                                                         if ($LOG) {
 433                                                                 run("$IPTABLES -t nat -A $CHAIN_NAT_SOURCE @nat_options @log_limit_options -j LOG --log-prefix 'SNAT '");
 434                                                         }
 435                                                         run("$IPTABLES -t nat -A $CHAIN_NAT_SOURCE @nat_options -j SNAT --to-source $nat_address");
 436                                                 }
 437                                         }
 438
 439                                         push(@options, @source_options);
 440                                         push(@options, @destination_options);
 441
 442                                         # Insert firewall rule.
 443                                         if ($LOG && !$NAT) {
 444                                                 run("$IPTABLES -A $chain @options @log_limit_options -j LOG --log-prefix '$chain '");
 445                                         }
 446                                         run("$IPTABLES -A $chain @options -j $target");
 447
 448                                         # Handle forwarding rules and add corresponding rules for firewall access.
 449                                         if ($chain eq $CHAIN_FORWARD) {
 450                                                 # If the firewall is part of the destination subnet and access to the destination network
 451                                                 # is granted/forbidden for any network that the firewall itself is part of, we grant/forbid access
 452                                                 # for the firewall, too.
 453                                                 if ($firewall_is_in_destination_subnet && ($target ~~ @special_input_targets)) {
 454                                                         if ($LOG && !$NAT) {
 455                                                                 run("$IPTABLES -A $CHAIN_INPUT @options @log_limit_options -j LOG --log-prefix '$CHAIN_INPUT '");
 456                                                         }
 457                                                         run("$IPTABLES -A $CHAIN_INPUT @options -j $target");
 458                                                 }
 459
 460                                                 # Likewise.
 461                                                 if ($firewall_is_in_source_subnet && ($target ~~ @special_output_targets)) {
 462                                                         if ($LOG && !$NAT) {
 463                                                                 run("$IPTABLES -A $CHAIN_OUTPUT @options @log_limit_options -j LOG --log-prefix '$CHAIN_OUTPUT '");
 464                                                         }
 465                                                         run("$IPTABLES -A $CHAIN_OUTPUT @options -j $target");
 466                                                 }
 467                                         }
 468                                 }
 469                         }
 470                 }
 471         }
 472 }
 473
 474 # Formats the given timestamp into the iptables format which is "hh:mm" UTC.
 475 sub format_time {
 476         my $val = shift;
 477
 478         # Convert the given time into minutes.
 479         my $minutes = &time_convert_to_minutes($val);
 480
 481         # Move the timestamp into UTC.
 482         $minutes += &time_utc_offset();
 483
 484         # Make sure $minutes is between 00:00 and 23:59.
 485         if ($minutes < 0) {
 486                 $minutes += 1440;
 487         }
 488
 489         if ($minutes > 1440) {
 490                 $minutes -= 1440;
 491         }
 492
 493         # Format as hh:mm.
 494         return sprintf("%02d:%02d", $minutes / 60, $minutes % 60);
 495 }
 496
 497 # Calculates the offsets in minutes from the local timezone to UTC.
 498 sub time_utc_offset {
 499         my @localtime = localtime(time);
 500         my @gmtime = gmtime(time);
 501
 502         return ($gmtime[2] * 60 + $gmtime[1] % 60) - ($localtime[2] * 60 + $localtime[1] % 60);
 503 }
 504
 505 # Takes a timestamp like "14:00" and converts it into minutes since midnight.
 506 sub time_convert_to_minutes {
 507         my ($hrs, $min) = split(":", shift);
 508
 509         return ($hrs * 60) + $min;
 510 }
 511
 512 sub p2pblock {
 513         my $search_action;
 514         my $target;
 515
 516         if ($fwdfwsettings{"POLICY"} eq "MODE1") {
 517                 $search_action = "on";
 518                 $target = "ACCEPT";
 519         } else {
 520                 $search_action = "off";
 521                 $target = "DROP";
 522         }
 523
 524         open(FILE, "<$p2pfile") or die "Unable to read $p2pfile";
 525         my @protocols = ();
 526         foreach my $p2pentry (<FILE>) {
 527                 my @p2pline = split(/\;/, $p2pentry);
 528                 next unless ($p2pline[2] eq $search_action);
 529
 530                 push(@protocols, "--$p2pline[1]");
 531         }
 532         close(FILE);
 533
 534         if (@protocols) {
 535                 run("$IPTABLES -A FORWARDFW -m ipp2p @protocols -j $target");
 536         }
 537 }
 538
 539 sub get_protocols {
 540         my $hash = shift;
 541         my $key = shift;
 542
 543         my $uses_source_ports = ($$hash{$key}[7] eq "ON");
 544         my $uses_services = ($$hash{$key}[11] eq "ON");
 545
 546         my @protocols = ();
 547
 548         # Rules which don't have source ports or services (like ICMP, ESP, ...).
 549         if (!$uses_source_ports && !$uses_services) {
 550                 push(@protocols, $$hash{$key}[8]);
 551
 552         # Rules which either use ports or services.
 553         } elsif ($uses_source_ports || $uses_services) {
 554                 # Check if service group or service
 555                 if ($$hash{$key}[14] eq 'cust_srv') {
 556                         push(@protocols, &fwlib::get_srv_prot($$hash{$key}[15]));
 557
 558                 } elsif($$hash{$key}[14] eq 'cust_srvgrp'){
 559                         my $protos = &fwlib::get_srvgrp_prot($$hash{$key}[15]);
 560                         push(@protocols, split(",", $protos));
 561
 562                 } else {
 563                         # Fetch the protocol for this rule.
 564                         my $protocol = lc($$hash{$key}[8]);
 565
 566                         # Fetch source and destination ports for this rule.
 567                         my $source_ports = $$hash{$key}[10];
 568                         my $destination_ports = $$hash{$key}[15];
 569
 570                         # Check if ports are set for protocols which do not support ports.
 571                         if (!($protocol ~~ @PROTOCOLS_WITH_PORTS) && ($source_ports || $destination_ports)) {
 572                                 print_error("$protocol does not support ports");
 573                                 return ();
 574                         }
 575
 576                         push(@protocols, $protocol);
 577                 }
 578         }
 579
 580         # Remove all empty elements
 581         @protocols = map { $_ ? $_ : () } @protocols;
 582
 583         # If no protocol has been defined, we assume "all".
 584         if (!@protocols) {
 585                 push(@protocols, "all");
 586         }
 587
 588         # Make all protocol names lowercase.
 589         @protocols = map { lc } @protocols;
 590
 591         return @protocols;
 592 }
 593
 594 sub get_protocol_options {
 595         my $hash = shift;
 596         my $key  = shift;
 597         my $protocol = shift;
 598         my $nat_options_wanted = shift;
 599         my @options = ();
 600
 601         # Nothing to do if no protocol is specified.
 602         if ($protocol eq "all") {
 603                 return @options;
 604         } else {
 605                 push(@options, ("-p", $protocol));
 606         }
 607
 608         if ($protocol ~~ @PROTOCOLS_WITH_PORTS) {
 609                 # Process source ports.
 610                 my $use_src_ports = ($$hash{$key}[7] eq "ON");
 611                 my $src_ports     = $$hash{$key}[10];
 612
 613                 if ($use_src_ports && $src_ports) {
 614                         push(@options, &format_ports($src_ports, "src"));
 615                 }
 616
 617                 # Process destination ports.
 618                 my $use_dst_ports  = ($$hash{$key}[11] eq "ON");
 619                 my $use_dnat       = (($$hash{$key}[28] eq "ON") && ($$hash{$key}[31] eq "dnat"));
 620
 621                 if ($use_dst_ports) {
 622                         my $dst_ports_mode = $$hash{$key}[14];
 623                         my $dst_ports      = $$hash{$key}[15];
 624
 625                         if (($dst_ports_mode eq "TGT_PORT") && $dst_ports) {
 626                                 if ($nat_options_wanted && $use_dnat && $$hash{$key}[30]) {
 627                                         $dst_ports = $$hash{$key}[30];
 628                                 }
 629                                 push(@options, &format_ports($dst_ports, "dst"));
 630
 631                         } elsif ($dst_ports_mode eq "cust_srv") {
 632                                 if ($protocol eq "ICMP") {
 633                                         push(@options, ("--icmp-type", &fwlib::get_srv_port($dst_ports, 3, "ICMP")));
 634                                 } else {
 635                                         $dst_ports = &fwlib::get_srv_port($dst_ports, 1, uc($protocol));
 636                                         push(@options, &format_ports($dst_ports, "dst"));
 637                                 }
 638
 639                         } elsif ($dst_ports_mode eq "cust_srvgrp") {
 640                                 push(@options, &fwlib::get_srvgrp_port($dst_ports, uc($protocol)));
 641                         }
 642                 }
 643         }
 644
 645         # Check if a single ICMP type is selected.
 646         if ($protocol eq "icmp") {
 647                 my $icmp_type = $$hash{$key}[9];
 648
 649                 if (($icmp_type ne "All ICMP-Types") && $icmp_type) {
 650                         push(@options, ("--icmp-type", $icmp_type));
 651                 }
 652         }
 653
 654         return @options;
 655 }
 656
 657 sub format_ports {
 658         my $ports = shift;
 659         my $type = shift;
 660
 661         my $arg;
 662         if ($type eq "src") {
 663                 $arg = "--sport";
 664         } elsif ($type eq "dst") {
 665                 $arg = "--dport";
 666         }
 667
 668         my @options = ();
 669
 670         if ($ports =~ /\|/) {
 671                 $ports =~ s/\|/,/g;
 672                 push(@options, ("-m", "multiport"));
 673         }
 674
 675         if ($ports) {
 676                 push(@options, ($arg, $ports));
 677         }
 678
 679         return @options;
 680 }
 681
 682 sub get_dnat_target_port {
 683         my $hash = shift;
 684         my $key  = shift;
 685
 686         if ($$hash{$key}[14] eq "TGT_PORT") {
 687                 my $port = $$hash{$key}[15];
 688                 my $external_port = $$hash{$key}[30];
 689
 690                 if ($external_port && ($port ne $external_port)) {
 691                         return $$hash{$key}[15];
 692                 }
 693         }
 694 }
 695
 696 sub add_dnat_mangle_rules {
 697         my $nat_address = shift;
 698         my $interface = shift;
 699         my @options = @_;
 700
 701         my $mark = 0;
 702         foreach my $zone ("GREEN", "BLUE", "ORANGE") {
 703                 $mark++;
 704
 705                 # Skip rule if not all required information exists.
 706                 next unless (exists $defaultNetworks{$zone . "_NETADDRESS"});
 707                 next unless (exists $defaultNetworks{$zone . "_NETMASK"});
 708
 709                 next if ($interface && $interface ne $defaultNetworks{$zone . "_DEV"});
 710
 711                 my @mangle_options = @options;
 712
 713                 my $netaddress = $defaultNetworks{$zone . "_NETADDRESS"};
 714                 $netaddress .= "/" . $defaultNetworks{$zone . "_NETMASK"};
 715
 716                 push(@mangle_options, ("-s", $netaddress, "-d", $nat_address));
 717                 push(@mangle_options, ("-j", "MARK", "--set-mark", $mark));
 718
 719                 run("$IPTABLES -t mangle -A $CHAIN_MANGLE_NAT_DESTINATION_FIX @mangle_options");
 720         }
 721 }
 722
 723 sub make_log_limit_options {
 724         my @options = ("-m", "limit");
 725
 726         # Maybe we should get this from the configuration.
 727         my $limit = 10;
 728
 729         # We limit log messages to $limit messages per minute.
 730         push(@options, ("--limit", "$limit/min"));
 731
 732         # And we allow bursts of 2x $limit.
 733         push(@options, ("--limit-burst", $limit * 2));
 734
 735         return @options;
 736 }
 737
 738 sub firewall_is_in_subnet {
 739         my $subnet = shift;
 740
 741         # ORANGE is missing here, because nothing may ever access
 742         # the firewall from this network.
 743         my $address = &fwlib::get_internal_firewall_ip_address($subnet, 0);
 744
 745         if ($address) {
 746                 return 1;
 747         }
 748
 749         return 0;
 750 }