html/cgi-bin/ids.cgi

   1 #!/usr/bin/perl
   2 ###############################################################################
   3 #                                                                             #
   4 # IPFire.org - A linux based firewall                                         #
   5 # Copyright (C) 2007-2020  IPFire Team  <info@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 # enable only the following on debugging purpose
  25 #use warnings;
  26 #use CGI::Carp 'fatalsToBrowser';
  27
  28 require '/var/ipfire/general-functions.pl';
  29 require "${General::swroot}/lang.pl";
  30 require "${General::swroot}/header.pl";
  31 require "${General::swroot}/ids-functions.pl";
  32 require "${General::swroot}/network-functions.pl";
  33
  34 # Import ruleset providers file.
  35 require "$IDS::rulesetsourcesfile";
  36
  37 my %color = ();
  38 my %mainsettings = ();
  39 my %idsrules = ();
  40 my %idssettings=();
  41 my %used_providers=();
  42 my %cgiparams=();
  43 my %checked=();
  44 my %selected=();
  45 my %ignored=();
  46
  47 # Read-in main settings, for language, theme and colors.
  48 &General::readhash("${General::swroot}/main/settings", \%mainsettings);
  49 &General::readhash("/srv/web/ipfire/html/themes/ipfire/include/colors.txt", \%color);
  50
  51 # Get the available network zones, based on the config type of the system and store
  52 # the list of zones in an array.
  53 my @network_zones = &Network::get_available_network_zones();
  54
  55 # Check if openvpn is started and add it to the array of network zones.
  56 if ( -e "/var/run/openvpn.pid") {
  57         push(@network_zones, "ovpn");
  58 }
  59
  60 my $errormessage;
  61
  62 # Create files if they does not exist yet.
  63 &IDS::check_and_create_filelayout();
  64
  65 # Hash which contains the colour code of a network zone.
  66 my %colourhash = (
  67         'red' => $Header::colourred,
  68         'green' => $Header::colourgreen,
  69         'blue' => $Header::colourblue,
  70         'orange' => $Header::colourorange,
  71         'ovpn' => $Header::colourovpn
  72 );
  73
  74 &Header::showhttpheaders();
  75
  76 #Get GUI values
  77 &Header::getcgihash(\%cgiparams);
  78
  79 ## Add/edit an entry to the ignore file.
  80 #
  81 if (($cgiparams{'WHITELIST'} eq $Lang::tr{'add'}) || ($cgiparams{'WHITELIST'} eq $Lang::tr{'update'})) {
  82
  83         # Check if any input has been performed.
  84         if ($cgiparams{'IGNORE_ENTRY_ADDRESS'} ne '') {
  85
  86                 # Check if the given input is no valid IP-address or IP-address with subnet, display an error message.
  87                 if ((!&General::validip($cgiparams{'IGNORE_ENTRY_ADDRESS'})) && (!&General::validipandmask($cgiparams{'IGNORE_ENTRY_ADDRESS'}))) {
  88                         $errormessage = "$Lang::tr{'guardian invalid address or subnet'}";
  89                 }
  90         } else {
  91                 $errormessage = "$Lang::tr{'guardian empty input'}";
  92         }
  93
  94         # Go further if there was no error.
  95         if ($errormessage eq '') {
  96                 my %ignored = ();
  97                 my $id;
  98                 my $status;
  99
 100                 # Assign hash values.
 101                 my $new_entry_address = $cgiparams{'IGNORE_ENTRY_ADDRESS'};
 102                 my $new_entry_remark = $cgiparams{'IGNORE_ENTRY_REMARK'};
 103
 104                 # Read-in ignoredfile.
 105                 &General::readhasharray($IDS::ignored_file, \%ignored);
 106
 107                 # Check if we should edit an existing entry and got an ID.
 108                 if (($cgiparams{'WHITELIST'} eq $Lang::tr{'update'}) && ($cgiparams{'ID'})) {
 109                         # Assin the provided id.
 110                         $id = $cgiparams{'ID'};
 111
 112                         # Undef the given ID.
 113                         undef($cgiparams{'ID'});
 114
 115                         # Grab the configured status of the corresponding entry.
 116                         $status = $ignored{$id}[2];
 117                 } else {
 118                         # Each newly added entry automatically should be enabled.
 119                         $status = "enabled";
 120
 121                         # Generate the ID for the new entry.
 122                         #
 123                         # Sort the keys by their ID and store them in an array.
 124                         my @keys = sort { $a <=> $b } keys %ignored;
 125
 126                         # Reverse the key array.
 127                         my @reversed = reverse(@keys);
 128
 129                         # Obtain the last used id.
 130                         my $last_id = @reversed[0];
 131
 132                         # Increase the last id by one and use it as id for the new entry.
 133                         $id = ++$last_id;
 134                 }
 135
 136                 # Add/Modify the entry to/in the ignored hash.
 137                 $ignored{$id} = ["$new_entry_address", "$new_entry_remark", "$status"];
 138
 139                 # Write the changed ignored hash to the ignored file.
 140                 &General::writehasharray($IDS::ignored_file, \%ignored);
 141
 142                 # Regenerate the ignore file.
 143                 &IDS::generate_ignore_file();
 144         }
 145
 146         # Check if the IDS is running.
 147         if(&IDS::ids_is_running()) {
 148                 # Call suricatactrl to perform a reload.
 149                 &IDS::call_suricatactrl("reload");
 150         }
 151
 152 ## Toggle Enabled/Disabled for an existing entry on the ignore list.
 153 #
 154
 155 } elsif ($cgiparams{'WHITELIST'} eq $Lang::tr{'toggle enable disable'}) {
 156         my %ignored = ();
 157
 158         # Only go further, if an ID has been passed.
 159         if ($cgiparams{'ID'}) {
 160                 # Assign the given ID.
 161                 my $id = $cgiparams{'ID'};
 162
 163                 # Undef the given ID.
 164                 undef($cgiparams{'ID'});
 165
 166                 # Read-in ignoredfile.
 167                 &General::readhasharray($IDS::ignored_file, \%ignored);
 168
 169                 # Grab the configured status of the corresponding entry.
 170                 my $status = $ignored{$id}[2];
 171
 172                 # Switch the status.
 173                 if ($status eq "disabled") {
 174                         $status = "enabled";
 175                 } else {
 176                         $status = "disabled";
 177                 }
 178
 179                 # Modify the status of the existing entry.
 180                 $ignored{$id} = ["$ignored{$id}[0]", "$ignored{$id}[1]", "$status"];
 181
 182                 # Write the changed ignored hash to the ignored file.
 183                 &General::writehasharray($IDS::ignored_file, \%ignored);
 184
 185                 # Regenerate the ignore file.
 186                 &IDS::generate_ignore_file();
 187
 188                 # Check if the IDS is running.
 189                 if(&IDS::ids_is_running()) {
 190                         # Call suricatactrl to perform a reload.
 191                         &IDS::call_suricatactrl("reload");
 192                 }
 193         }
 194
 195 ## Remove entry from ignore list.
 196 #
 197 } elsif ($cgiparams{'WHITELIST'} eq $Lang::tr{'remove'}) {
 198         my %ignored = ();
 199
 200         # Read-in ignoredfile.
 201         &General::readhasharray($IDS::ignored_file, \%ignored);
 202
 203         # Drop entry from the hash.
 204         delete($ignored{$cgiparams{'ID'}});
 205
 206         # Undef the given ID.
 207         undef($cgiparams{'ID'});
 208
 209         # Write the changed ignored hash to the ignored file.
 210         &General::writehasharray($IDS::ignored_file, \%ignored);
 211
 212         # Regenerate the ignore file.
 213         &IDS::generate_ignore_file();
 214
 215         # Check if the IDS is running.
 216         if(&IDS::ids_is_running()) {
 217                 # Call suricatactrl to perform a reload.
 218                 &IDS::call_suricatactrl("reload");
 219         }
 220 }
 221
 222 # Check if the page is locked, in this case, the ids_page_lock_file exists.
 223 if (-e $IDS::ids_page_lock_file) {
 224         # Lock the webpage and print notice about autoupgrade of the ruleset
 225         # is in progess.
 226         &working_notice("$Lang::tr{'ids ruleset autoupdate in progress'}");
 227
 228         # Loop and check if the file still exists.
 229         while(-e $IDS::ids_page_lock_file) {
 230                 # Sleep for a second and re-check.
 231                 sleep 1;
 232         }
 233
 234         # Page has been unlocked, perform a reload.
 235         &reload();
 236 }
 237
 238 # Check if any error has been stored.
 239 if (-e $IDS::storederrorfile) {
 240         # Open file to read in the stored error message.
 241         open(FILE, "<$IDS::storederrorfile") or die "Could not open $IDS::storederrorfile. $!\n";
 242
 243         # Read the stored error message.
 244         $errormessage = <FILE>;
 245
 246         # Close file.
 247         close (FILE);
 248
 249         # Delete the file, which is now not longer required.
 250         unlink($IDS::storederrorfile);
 251 }
 252
 253 # Gather ruleset details.
 254 if ($cgiparams{'RULESET'}) {
 255         ## Grab all available rules and store them in the idsrules hash.
 256         #
 257
 258         # Get enabled providers.
 259         my @enabled_providers = &IDS::get_enabled_providers();
 260
 261         # Open rules directory and do a directory listing.
 262         opendir(DIR, $IDS::rulespath) or die $!;
 263                 # Loop through the direcory.
 264                 while (my $file = readdir(DIR)) {
 265
 266                         # We only want files.
 267                         next unless (-f "$IDS::rulespath/$file");
 268
 269                         # Ignore empty files.
 270                         next if (-z "$IDS::rulespath/$file");
 271
 272                         # Use a regular expression to find files ending in .rules
 273                         next unless ($file =~ m/\.rules$/);
 274
 275                         # Ignore files which are not read-able.
 276                         next unless (-R "$IDS::rulespath/$file");
 277
 278                         # Skip whitelist rules file.
 279                         next if( $file eq "whitelist.rules");
 280
 281                         # Splitt vendor from filename.
 282                         my @filename_parts = split(/-/, $file);
 283
 284                         # Assign vendor name for easy processing.
 285                         my $vendor = @filename_parts[0];
 286
 287                         # Skip rulefile if the provider is disabled.
 288                         next unless ($vendor ~~ @enabled_providers);
 289
 290                         # Call subfunction to read-in rulefile and add rules to
 291                         # the idsrules hash.
 292                         &readrulesfile("$file");
 293                 }
 294
 295         closedir(DIR);
 296
 297         # Loop through the array of used providers.
 298         foreach my $provider (@enabled_providers) {
 299                 # Gather used rulefiles.
 300                 my @used_rulesfiles = &IDS::read_used_provider_rulesfiles($provider);
 301
 302                 # Loop through the array of used rulesfiles.
 303                 foreach my $rulefile (@used_rulesfiles) {
 304                         # Check if the current rulefile exists in the %idsrules hash.
 305                         # If not, the file probably does not exist anymore or contains
 306                         # no rules.
 307                         if($idsrules{$rulefile}) {
 308                                 # Add the rulefile state to the %idsrules hash.
 309                                 $idsrules{$rulefile}{'Rulefile'}{'State'} = "on";
 310                         }
 311                 }
 312         }
 313 }
 314
 315 # Save ruleset.
 316 if ($cgiparams{'RULESET'} eq $Lang::tr{'ids apply'}) {
 317         # Arrays to store which rulefiles have been enabled and will be used.
 318         my @enabled_rulefiles;
 319
 320         # Hash to store the user-enabled and disabled sids.
 321         my %enabled_disabled_sids;
 322
 323         # Store if a restart of suricata is required.
 324         my $suricata_restart_required;
 325
 326         # Loop through the hash of idsrules.
 327         foreach my $rulefile(keys %idsrules) {
 328                 # Check if the state of the rulefile has been changed.
 329                 unless ($cgiparams{$rulefile} eq $idsrules{$rulefile}{'Rulefile'}{'State'}) {
 330                         # A restart of suricata is required to apply the changes of the used rulefiles.
 331                         $suricata_restart_required = 1;
 332                 }
 333
 334                 # Check if the rulefile is enabled.
 335                 if ($cgiparams{$rulefile} eq "on") {
 336                         # Add rulefile to the array of enabled rulefiles.
 337                         push(@enabled_rulefiles, $rulefile);
 338
 339                         # Drop item from cgiparams hash.
 340                         delete $cgiparams{$rulefile};
 341                 }
 342         }
 343
 344         # Read-in the files for enabled/disabled sids.
 345         # This will be done by calling the read_enabled_disabled_sids_file function two times
 346         # and merge the returned hashes together into the enabled_disabled_sids hash.
 347         %enabled_disabled_sids = (
 348                 &read_enabled_disabled_sids_file($IDS::disabled_sids_file),
 349                 &read_enabled_disabled_sids_file($IDS::enabled_sids_file));
 350
 351         # Loop through the hash of idsrules.
 352         foreach my $rulefile (keys %idsrules) {
 353                 # Loop through the single rules of the rulefile.
 354                 foreach my $sid (keys %{$idsrules{$rulefile}}) {
 355                         # Skip the current sid if it is not numeric.
 356                         next unless ($sid =~ /\d+/ );
 357
 358                         # Check if there exists a key in the cgiparams hash for this sid.
 359                         if (exists($cgiparams{$sid})) {
 360                                 # Look if the rule is disabled.
 361                                 if ($idsrules{$rulefile}{$sid}{'State'} eq "off") {
 362                                         # Check if the state has been set to 'on'.
 363                                         if ($cgiparams{$sid} eq "on") {
 364                                                 # Add/Modify the sid to/in the enabled_disabled_sids hash.
 365                                                 $enabled_disabled_sids{$sid} = "enabled";
 366
 367                                                 # Drop item from cgiparams hash.
 368                                                 delete $cgiparams{$rulefile}{$sid};
 369                                         }
 370                                 }
 371                         } else {
 372                                 # Look if the rule is enabled.
 373                                 if ($idsrules{$rulefile}{$sid}{'State'} eq "on") {
 374                                         # Check if the state is 'on' and should be disabled.
 375                                         # In this case there is no entry
 376                                         # for the sid in the cgiparams hash.
 377                                         # Add/Modify it to/in the enabled_disabled_sids hash.
 378                                         $enabled_disabled_sids{$sid} = "disabled";
 379
 380                                         # Drop item from cgiparams hash.
 381                                         delete $cgiparams{$rulefile}{$sid};
 382                                 }
 383                         }
 384                 }
 385         }
 386
 387         # Open enabled sid's file for writing.
 388         open(ENABLED_FILE, ">$IDS::enabled_sids_file") or die "Could not write to $IDS::enabled_sids_file. $!\n";
 389
 390         # Open disabled sid's file for writing.
 391         open(DISABLED_FILE, ">$IDS::disabled_sids_file") or die "Could not write to $IDS::disabled_sids_file. $!\n";
 392
 393         # Write header to the files.
 394         print ENABLED_FILE "#Autogenerated file. Any custom changes will be overwritten!\n";
 395         print DISABLED_FILE "#Autogenerated file. Any custom changes will be overwritten!\n";
 396
 397         # Check if the hash for enabled/disabled files contains any entries.
 398         if (%enabled_disabled_sids) {
 399                 # Loop through the hash.
 400                 foreach my $sid (keys %enabled_disabled_sids) {
 401                         # Check if the sid is enabled.
 402                         if ($enabled_disabled_sids{$sid} eq "enabled") {
 403                                 # Print the sid to the enabled_sids file.
 404                                 print ENABLED_FILE "enablesid $sid\n";
 405                         # Check if the sid is disabled.
 406                         } elsif ($enabled_disabled_sids{$sid} eq "disabled") {
 407                                 # Print the sid to the disabled_sids file.
 408                                 print DISABLED_FILE "disablesid $sid\n";
 409                         # Something strange happende - skip the current sid.
 410                         } else {
 411                                 next;
 412                         }
 413                 }
 414         }
 415
 416         # Close file for enabled_sids after writing.
 417         close(ENABLED_FILE);
 418
 419         # Close file for disabled_sids after writing.
 420         close(DISABLED_FILE);
 421
 422         # Handle enabled / disabled rulefiles.
 423         #
 424         # Get enabled providers.
 425         my @enabled_providers = &IDS::get_enabled_providers();
 426
 427         # Loop through the array of enabled providers.
 428         foreach my $provider(@enabled_providers) {
 429                 # Array to store the rulefiles which belong to the current processed provider.
 430                 my @provider_rulefiles = ();
 431
 432                 # Loop through the array of enabled rulefiles.
 433                 foreach my $rulesfile (@enabled_rulefiles) {
 434                         # Split the rulefile name.
 435                         my @filename_parts = split(/-/, "$rulesfile");
 436
 437                         # Assign vendor name for easy processings.
 438                         my $vendor = @filename_parts[0];
 439
 440                         # Check if the rulesvendor is our current processed enabled provider.
 441                         if ("$vendor" eq "$provider") {
 442                                 # Add the rulesfile to the array of provider rulesfiles.
 443                                 push(@provider_rulefiles, $rulesfile);
 444                         }
 445
 446                         # Check if any rulesfiles have been found for this provider.
 447                         if (@provider_rulefiles) {
 448                                 # Call function and write the providers used rulesfile file.
 449                                 &IDS::write_used_provider_rulefiles_file($provider, @provider_rulefiles);
 450                         }
 451                 }
 452         }
 453
 454         # Call function to generate and write the used rulefiles file.
 455         &IDS::write_main_used_rulefiles_file(@enabled_providers);
 456
 457         # Lock the webpage and print message.
 458         &working_notice("$Lang::tr{'ids apply ruleset changes'}");
 459
 460         # Call oinkmaster to alter the ruleset.
 461         &IDS::oinkmaster();
 462
 463         # Check if the IDS is running.
 464         if(&IDS::ids_is_running()) {
 465                 # Check if a restart of suricata is required.
 466                 if ($suricata_restart_required) {
 467                         # Call suricatactrl to perform the restart.
 468                         &IDS::call_suricatactrl("restart");
 469                 } else {
 470                         # Call suricatactrl to perform a reload.
 471                         &IDS::call_suricatactrl("reload");
 472                 }
 473         }
 474
 475         # Reload page.
 476         &reload();
 477
 478 # Download new ruleset.
 479 } elsif ($cgiparams{'RULESET'} eq $Lang::tr{'update ruleset'}) {
 480         # Check if the red device is active.
 481         unless (-e "${General::swroot}/red/active") {
 482                 $errormessage = "$Lang::tr{'could not download latest updates'} - $Lang::tr{'system is offline'}";
 483         }
 484
 485         # Check if enought free disk space is availabe.
 486         if(&IDS::checkdiskspace()) {
 487                 $errormessage = "$Lang::tr{'not enough disk space'}";
 488         }
 489
 490         # Check if any errors happend.
 491         unless ($errormessage) {
 492                 # Lock the webpage and print notice about downloading
 493                 # a new ruleset.
 494                 &working_notice("$Lang::tr{'ids download new ruleset'}");
 495
 496                 # Call subfunction to download the ruleset.
 497                 if(&IDS::downloadruleset()) {
 498                         $errormessage = $Lang::tr{'could not download latest updates'};
 499
 500                         # Call function to store the errormessage.
 501                         &IDS::_store_error_message($errormessage);
 502
 503                         # Preform a reload of the page.
 504                         &reload();
 505                 } else {
 506                         # Call subfunction to launch oinkmaster.
 507                         &IDS::oinkmaster();
 508
 509                         # Check if the IDS is running.
 510                         if(&IDS::ids_is_running()) {
 511                                 # Call suricatactrl to perform a reload.
 512                                 &IDS::call_suricatactrl("reload");
 513                         }
 514
 515                         # Perform a reload of the page.
 516                         &reload();
 517                 }
 518         }
 519 # Save IDS settings.
 520 } elsif ($cgiparams{'IDS'} eq $Lang::tr{'save'}) {
 521         my %oldidssettings;
 522         my $reload_page;
 523         my $monitored_zones = 0;
 524
 525         # Read-in current (old) IDS settings.
 526         &General::readhash("$IDS::ids_settings_file", \%oldidssettings);
 527
 528         # Prevent form name from been stored in conf file.
 529         delete $cgiparams{'IDS'};
 530
 531         # Check if the IDS should be enabled.
 532         if ($cgiparams{'ENABLE_IDS'} eq "on") {
 533                 # Check if any ruleset is available. Otherwise abort and display an error.
 534                 unless(%used_providers) {
 535                         $errormessage = $Lang::tr{'ids no ruleset available'};
 536                 }
 537
 538                 # Loop through the array of available interfaces.
 539                 foreach my $zone (@network_zones) {
 540                         # Convert interface name into upper case.
 541                         my $zone_upper = uc($zone);
 542
 543                         # Check if the IDS is enabled for this interaces.
 544                         if ($cgiparams{"ENABLE_IDS_$zone_upper"}) {
 545                                 # Increase count.
 546                                 $monitored_zones++;
 547                         }
 548                 }
 549
 550                 # Check if at least one zone should be monitored, or show an error.
 551                 unless ($monitored_zones >= 1) {
 552                         $errormessage = $Lang::tr{'ids no network zone'};
 553                 }
 554         }
 555
 556         # Go on if there are no error messages.
 557         if (!$errormessage) {
 558                 # Store settings into settings file.
 559                 &General::writehash("$IDS::ids_settings_file", \%cgiparams);
 560         }
 561
 562         # Check if the the automatic rule update hass been touched.
 563         if($cgiparams{'AUTOUPDATE_INTERVAL'} ne $oldidssettings{'AUTOUPDATE_INTERVAL'}) {
 564                 # Call suricatactrl to set the new interval.
 565                 &IDS::call_suricatactrl("cron", $cgiparams{'AUTOUPDATE_INTERVAL'});
 566         }
 567
 568         # Generate file to store the home net.
 569         &IDS::generate_home_net_file();
 570
 571         # Generate file to the store the DNS servers.
 572         &IDS::generate_dns_servers_file();
 573
 574         # Generate file to store the HTTP ports.
 575         &IDS::generate_http_ports_file();
 576
 577         # Write the modify sid's file and pass the taken ruleaction.
 578         &IDS::write_modify_sids_file();
 579
 580         # Check if "MONITOR_TRAFFIC_ONLY" has been changed.
 581         if($cgiparams{'MONITOR_TRAFFIC_ONLY'} ne $oldidssettings{'MONITOR_TRAFFIC_ONLY'}) {
 582                 # Check if a ruleset exists.
 583                 if (%used_providers) {
 584                         # Lock the webpage and print message.
 585                         &working_notice("$Lang::tr{'ids working'}");
 586
 587                         # Call oinkmaster to alter the ruleset.
 588                         &IDS::oinkmaster();
 589
 590                         # Set reload_page to "True".
 591                         $reload_page="True";
 592                 }
 593         }
 594
 595         # Check if the IDS currently is running.
 596         if(&IDS::ids_is_running()) {
 597                 # Check if ENABLE_IDS is set to on.
 598                 if($cgiparams{'ENABLE_IDS'} eq "on") {
 599                         # Call suricatactrl to perform a reload of suricata.
 600                         &IDS::call_suricatactrl("reload");
 601                 } else {
 602                         # Call suricatactrl to stop suricata.
 603                         &IDS::call_suricatactrl("stop");
 604                 }
 605         } else {
 606                 # Call suricatactrl to start suricata.
 607                 &IDS::call_suricatactrl("start");
 608         }
 609
 610         # Check if the page should be reloaded.
 611         if ($reload_page) {
 612                 # Perform a reload of the page.
 613                 &reload();
 614         }
 615
 616 # Toggle Enable/Disable autoupdate for a provider
 617 } elsif ($cgiparams{'AUTOUPDATE'} eq $Lang::tr{'toggle enable disable'}) {
 618         my %used_providers = ();
 619
 620         # Only go further, if an ID has been passed.
 621         if ($cgiparams{'ID'}) {
 622                 # Assign the given ID.
 623                 my $id = $cgiparams{'ID'};
 624
 625                 # Undef the given ID.
 626                 undef($cgiparams{'ID'});
 627
 628                 # Read-in providers settings file.
 629                 &General::readhasharray($IDS::providers_settings_file, \%used_providers);
 630
 631                 # Grab the configured status of the corresponding entry.
 632                 my $status_autoupdate = $used_providers{$id}[2];
 633
 634                 # Switch the status.
 635                 if ($status_autoupdate eq "disabled") {
 636                         $status_autoupdate = "enabled";
 637                 } else {
 638                         $status_autoupdate = "disabled";
 639                 }
 640
 641                 # Modify the status of the existing entry.
 642                 $used_providers{$id} = ["$used_providers{$id}[0]", "$used_providers{$id}[1]", "$status_autoupdate", "$used_providers{$id}[3]"];
 643
 644                 # Write the changed hash to the providers settings file.
 645                 &General::writehasharray($IDS::providers_settings_file, \%used_providers);
 646         }
 647
 648 # Add/Edit a provider to the list of used providers.
 649 #
 650 } elsif (($cgiparams{'PROVIDERS'} eq "$Lang::tr{'add'}") || ($cgiparams{'PROVIDERS'} eq "$Lang::tr{'update'}")) {
 651         my %used_providers = ();
 652
 653         # Read-in providers settings file.
 654         &General::readhasharray("$IDS::providers_settings_file", \%used_providers);
 655
 656         # Assign some nice human-readable values.
 657         my $provider = $cgiparams{'PROVIDER'};
 658         my $subscription_code = $cgiparams{'SUBSCRIPTION_CODE'};
 659         my $status_autoupdate;
 660
 661         # Handle autoupdate checkbox.
 662         if ($cgiparams{'ENABLE_AUTOUPDATE'} eq "on") {
 663                 $status_autoupdate = "enabled";
 664         } else {
 665                 $status_autoupdate = "disabled";
 666         }
 667
 668         # Check if we are going to add a new provider.
 669         if ($cgiparams{'PROVIDERS'} eq "$Lang::tr{'add'}") {
 670                 # Loop through the hash of used providers.
 671                 foreach my $id ( keys %used_providers) {
 672                         # Check if the choosen provider is already in use.
 673                         if ($used_providers{$id}[0] eq "$provider") {
 674                                 # XXX - add to language file.
 675                                 # Assign error message.
 676                                 $errormessage = "The choosen provider is already in use.";
 677                         }
 678                 }
 679         }
 680
 681         # Check if the provider requires a subscription code.
 682         if ($IDS::Ruleset::Providers{$provider}{'requires_subscription'} eq "True") {
 683                 # Check if an subscription code has been provided.
 684                 if ($subscription_code) {
 685                         # Check if the code contains unallowed chars.
 686                         unless ($subscription_code =~ /^[a-z0-9]+$/) {
 687                                 $errormessage = $Lang::tr{'invalid input for subscription code'};
 688                         }
 689                 } else {
 690                         # Print an error message, that an subsription code is required for this
 691                         # provider.
 692                         $errormessage = $Lang::tr{'ids subscription code required'};
 693                 }
 694         }
 695
 696         # Go further if there was no error.
 697         if ($errormessage eq '') {
 698                 my $id;
 699                 my $status;
 700
 701                 # Check if we should edit an existing entry and got an ID.
 702                 if (($cgiparams{'PROVIDERS'} eq $Lang::tr{'update'}) && ($cgiparams{'ID'})) {
 703                         # Assin the provided id.
 704                         $id = $cgiparams{'ID'};
 705
 706                         # Undef the given ID.
 707                         undef($cgiparams{'ID'});
 708
 709                         # Grab the configured status of the corresponding entry.
 710                         $status = $used_providers{$id}[3];
 711                 } else {
 712                         # Each newly added entry automatically should be enabled.
 713                         $status = "enabled";
 714
 715                         # Generate the ID for the new entry.
 716                         #
 717                         # Sort the keys by their ID and store them in an array.
 718                         my @keys = sort { $a <=> $b } keys %used_providers;
 719
 720                         # Reverse the key array.
 721                         my @reversed = reverse(@keys);
 722
 723                         # Obtain the last used id.
 724                         my $last_id = @reversed[0];
 725
 726                         # Increase the last id by one and use it as id for the new entry.
 727                         $id = ++$last_id;
 728                 }
 729
 730                 # Add/Modify the entry to/in the used providers hash..
 731                 $used_providers{$id} = ["$provider", "$subscription_code", "$status_autoupdate", "$status"];
 732
 733                 # Write the changed hash to the providers settings file.
 734                 &General::writehasharray($IDS::providers_settings_file, \%used_providers);
 735
 736                 # Check if a new provider will be added.
 737                 if ($cgiparams{'PROVIDERS'} eq $Lang::tr{'add'}) {
 738                         # Lock the webpage and print notice about downloading
 739                         # a new ruleset.
 740                         &working_notice("$Lang::tr{'ids working'}");
 741
 742                         # Download the ruleset.
 743                         &IDS::downloadruleset($provider);
 744
 745                         # Extract the ruleset
 746                         &IDS::extractruleset($provider);
 747
 748                         # Move the ruleset.
 749                         &IDS::move_tmp_ruleset();
 750
 751                         # Cleanup temporary directory.
 752                         &IDS::cleanup_tmp_directory();
 753
 754                         # Create new empty file for used rulefiles
 755                         # for this provider.
 756                         &IDS::write_used_provider_rulefiles_file($provider);
 757
 758                         # Perform a reload of the page.
 759                         &reload();
 760                 }
 761
 762                 # Undefine providers flag.
 763                 undef($cgiparams{'PROVIDERS'});
 764         }
 765
 766 ## Toggle Enabled/Disabled for an existing provider.
 767 #
 768 } elsif ($cgiparams{'PROVIDERS'} eq $Lang::tr{'toggle enable disable'}) {
 769         my %used_providers = ();
 770
 771         # Only go further, if an ID has been passed.
 772         if ($cgiparams{'ID'}) {
 773                 # Assign the given ID.
 774                 my $id = $cgiparams{'ID'};
 775
 776                 # Undef the given ID.
 777                 undef($cgiparams{'ID'});
 778
 779                 # Read-in file which contains the provider settings.
 780                 &General::readhasharray($IDS::providers_settings_file, \%used_providers);
 781
 782                 # Grab the configured status of the corresponding entry.
 783                 my $status = $used_providers{$id}[3];
 784
 785                 # Switch the status.
 786                 if ($status eq "enabled") {
 787                         $status = "disabled";
 788                 } else {
 789                         $status = "enabled";
 790                 }
 791
 792                 # Modify the status of the existing entry.
 793                 $used_providers{$id} = ["$used_providers{$id}[0]", "$used_providers{$id}[1]", "$used_providers{$id}[2]", "$status"];
 794
 795                 # Write the changed hash to the providers settings file.
 796                 &General::writehasharray($IDS::providers_settings_file, \%used_providers);
 797
 798                 # Get all enabled providers.
 799                 my @enabled_providers = &IDS::get_enabled_providers();
 800
 801                 # Write the main providers include file.
 802                 &IDS::write_main_used_rulefiles_file(@enabled_providers);
 803
 804                 # Check if the IDS is running.
 805                 if(&IDS::ids_is_running()) {
 806                         # Gather the amount of enabled providers (elements in the array).
 807                         my $amount = @enabled_providers;
 808
 809                         # Check if there are still enabled ruleset providers.
 810                         if ($amount >= 1) {
 811                                 # Call suricatactrl to perform a restart.
 812                                 &IDS::call_suricatactrl("restart");
 813
 814                         # No active ruleset provider, suricata has to be stopped.
 815                         } else {
 816                                 # Stop suricata.
 817                                 &IDS::call_suricatactrl("stop");
 818                         }
 819                 }
 820
 821                 # Undefine providers flag.
 822                 undef($cgiparams{'PROVIDERS'});
 823         }
 824
 825 ## Remove provider from the list of used providers.
 826 #
 827 } elsif ($cgiparams{'PROVIDERS'} eq $Lang::tr{'remove'}) {
 828         my %used_providers = ();
 829
 830         # Read-in provider settings file.
 831         &General::readhasharray($IDS::providers_settings_file, \%used_providers);
 832
 833         # Grab the provider name bevore deleting it from hash.
 834         my $provider = $used_providers{$cgiparams{'ID'}}[0];
 835
 836         # Drop entry from the hash.
 837         delete($used_providers{$cgiparams{'ID'}});
 838
 839         # Undef the given ID.
 840         undef($cgiparams{'ID'});
 841
 842         # Write the changed hash to the provide settings file.
 843         &General::writehasharray($IDS::providers_settings_file, \%used_providers);
 844
 845         # Drop the stored ruleset file.
 846         &IDS::drop_dl_rulesfile($provider);
 847
 848         # Get the name of the provider rulessets include file.
 849         my $provider_used_rulefile = &get_used_provider_rulesfile_file($provider);
 850
 851         # Drop the file, it is not longer needed.
 852         unlink("$provider_used_rulefile");
 853
 854         # Regenerate ruleset.
 855         &IDS::oinkmaster();
 856
 857         # Gather all enabled providers.
 858         my @enabled_providers = &IDS::get_enabled_providers();
 859
 860         # Regenerate main providers include file.
 861         &IDS::write_main_used_rulefiles_file(@enabled_providers);
 862
 863         # Check if the IDS is running.
 864         if(&IDS::ids_is_running()) {
 865                 # Get amount of enabled providers.
 866                 my $amount = @enabled_providers;
 867
 868                 # Check if at least one enabled provider remains.
 869                 if ($amount >= 1) {
 870                         # Call suricatactrl to perform a reload.
 871                         &IDS::call_suricatactrl("restart");
 872
 873                 # Stop suricata if no enabled provider remains.
 874                 } else {
 875                         # Call suricatactrel to perform the stop.
 876                         &IDS::call_suricatactrl("stop");
 877                 }
 878         }
 879
 880         # Undefine providers flag.
 881         undef($cgiparams{'PROVIDERS'});
 882 }
 883
 884 &Header::openpage($Lang::tr{'intrusion detection system'}, 1, '');
 885
 886 &Header::openbigbox('100%', 'left', '', $errormessage);
 887
 888 &show_display_error_message();
 889
 890 if ($cgiparams{'RULESET'} eq "$Lang::tr{'ids customize ruleset'}" ) {
 891         &show_customize_ruleset();
 892 } elsif ($cgiparams{'PROVIDERS'} ne "") {
 893         &show_add_provider();
 894 } else {
 895         &show_mainpage();
 896 }
 897
 898 &Header::closebigbox();
 899 &Header::closepage();
 900
 901 #
 902 ## Tiny function to show if a error message happened.
 903 #
 904 sub show_display_error_message() {
 905         if ($errormessage) {
 906                 &Header::openbox('100%', 'left', $Lang::tr{'error messages'});
 907                         print "<class name='base'>$errormessage\n";
 908                         print "&nbsp;</class>\n";
 909                 &Header::closebox();
 910         }
 911 }
 912
 913 #
 914 ## Function to display the main IDS page.
 915 #
 916 sub show_mainpage() {
 917         # Read-in idssettings and provider settings.
 918         &General::readhash("$IDS::ids_settings_file", \%idssettings);
 919         &General::readhasharray("$IDS::providers_settings_file", \%used_providers);
 920
 921         # If no autoupdate intervall has been configured yet, set default value.
 922         unless(exists($idssettings{'AUTOUPDATE_INTERVAL'})) {
 923                 # Set default to "weekly".
 924                 $idssettings{'AUTOUPDATE_INTERVAL'} = 'weekly';
 925         }
 926
 927         # Read-in ignored hosts.
 928         &General::readhasharray("$IDS::settingsdir/ignored", \%ignored);
 929
 930         $checked{'ENABLE_IDS'}{'off'} = '';
 931         $checked{'ENABLE_IDS'}{'on'} = '';
 932         $checked{'ENABLE_IDS'}{$idssettings{'ENABLE_IDS'}} = "checked='checked'";
 933         $checked{'MONITOR_TRAFFIC_ONLY'}{'off'} = '';
 934         $checked{'MONITOR_TRAFFIC_ONLY'}{'on'} = '';
 935         $checked{'MONITOR_TRAFFIC_ONLY'}{$idssettings{'MONITOR_TRAFFIC_ONLY'}} = "checked='checked'";
 936         $selected{'AUTOUPDATE_INTERVAL'}{'off'} = '';
 937         $selected{'AUTOUPDATE_INTERVAL'}{'daily'} = '';
 938         $selected{'AUTOUPDATE_INTERVAL'}{'weekly'} = '';
 939         $selected{'AUTOUPDATE_INTERVAL'}{$idssettings{'AUTOUPDATE_INTERVAL'}} = "selected='selected'";
 940
 941         # Draw current state of the IDS
 942         &Header::openbox('100%', 'left', $Lang::tr{'intrusion detection system'});
 943
 944         # Check if the IDS is running and obtain the process-id.
 945         my $pid = &IDS::ids_is_running();
 946
 947         # Display some useful information, if suricata daemon is running.
 948         if ($pid) {
 949                 # Gather used memory.
 950                 my $memory = &get_memory_usage($pid);
 951
 952                 print <<END;
 953                         <table width='95%' cellspacing='0' class='tbl'>
 954                                 <tr>
 955                                         <th bgcolor='$color{'color20'}' colspan='3' align='left'><strong>$Lang::tr{'intrusion detection'}</strong></th>
 956                                 </tr>
 957
 958                                 <tr>
 959                                         <td class='base'>$Lang::tr{'guardian daemon'}</td>
 960                                         <td align='center' colspan='2' width='75%' bgcolor='${Header::colourgreen}'><font color='white'><strong>$Lang::tr{'running'}</strong></font></td>
 961                                 </tr>
 962
 963                                 <tr>
 964                                         <td class='base'></td>
 965                                         <td bgcolor='$color{'color20'}' align='center'><strong>PID</strong></td>
 966                                         <td bgcolor='$color{'color20'}' align='center'><strong>$Lang::tr{'memory'}</strong></td>
 967                                 </tr>
 968
 969                                 <tr>
 970                                         <td class='base'></td>
 971                                         <td bgcolor='$color{'color22'}' align='center'>$pid</td>
 972                                         <td bgcolor='$color{'color22'}' align='center'>$memory KB</td>
 973                                 </tr>
 974                         </table>
 975 END
 976         } else {
 977                 # Otherwise display a hint that the service is not launched.
 978                 print <<END;
 979                         <table width='95%' cellspacing='0' class='tbl'>
 980                                 <tr>
 981                                         <th bgcolor='$color{'color20'}' colspan='3' align='left'><strong>$Lang::tr{'intrusion detection'}</strong></th>
 982                                 </tr>
 983
 984                                 <tr>
 985                                         <td class='base'>$Lang::tr{'guardian daemon'}</td>
 986                                         <td align='center' width='75%' bgcolor='${Header::colourred}'><font color='white'><strong>$Lang::tr{'stopped'}</strong></font></td>
 987                                 </tr>
 988                         </table>
 989 END
 990         }
 991
 992         # Only show this area, if at least one ruleset provider is configured.
 993         if (%used_providers) {
 994
 995 print <<END
 996
 997                 <br><br><h2>$Lang::tr{'settings'}</h2>
 998
 999                 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
1000                         <table width='100%' border='0'>
1001                                 <tr>
1002                                         <td class='base' colspan='2'>
1003                                                 <input type='checkbox' name='ENABLE_IDS' $checked{'ENABLE_IDS'}{'on'}>&nbsp;$Lang::tr{'ids enable'}
1004                                         </td>
1005
1006                                         <td class='base' colspan='2'>
1007                                                 <input type='checkbox' name='MONITOR_TRAFFIC_ONLY' $checked{'MONITOR_TRAFFIC_ONLY'}{'on'}>&nbsp;$Lang::tr{'ids monitor traffic only'}
1008                                 </td>
1009                                 </tr>
1010
1011                                 <tr>
1012                                         <td><br><br></td>
1013                                         <td><br><br></td>
1014                                         <td><br><br></td>
1015                                         <td><br><br></td>
1016                                 </tr>
1017
1018                                 <tr>
1019                                         <td colspan='4'><b>$Lang::tr{'ids monitored interfaces'}</b><br></td>
1020                                 </tr>
1021
1022                                 <tr>
1023 END
1024 ;
1025
1026                 # Loop through the array of available networks and print config options.
1027                 foreach my $zone (@network_zones) {
1028                         my $checked_input;
1029                         my $checked_forward;
1030
1031                         # Convert current zone name to upper case.
1032                         my $zone_upper = uc($zone);
1033
1034                         # Set zone name.
1035                         my $zone_name = $zone;
1036
1037                         # Dirty hack to get the correct language string for the red zone.
1038                         if ($zone eq "red") {
1039                                 $zone_name = "red1";
1040                         }
1041
1042                         # Grab checkbox status from settings hash.
1043                         if ($idssettings{"ENABLE_IDS_$zone_upper"} eq "on") {
1044                                 $checked_input = "checked = 'checked'";
1045                         }
1046
1047                         print "<td class='base' width='20%'>\n";
1048                         print "<input type='checkbox' name='ENABLE_IDS_$zone_upper' $checked_input>\n";
1049                         print "&nbsp;$Lang::tr{'enabled on'}<font color='$colourhash{$zone}'> $Lang::tr{$zone_name}</font>\n";
1050                         print "</td>\n";
1051                 }
1052
1053 print <<END
1054                                 </tr>
1055
1056                                 <tr>
1057                                         <td><br><br></td>
1058                                         <td><br><br></td>
1059                                         <td><br><br></td>
1060                                         <td><br><br></td>
1061                                 </tr>
1062
1063                                 <tr>
1064                                         <td colspan='4'><b>$Lang::tr{'ids automatic rules update'}</b></td>
1065                                 </tr>
1066
1067                                 <tr>
1068                                         <td>
1069                                                 <select name='AUTOUPDATE_INTERVAL'>
1070                                                         <option value='off' $selected{'AUTOUPDATE_INTERVAL'}{'off'} >- $Lang::tr{'Disabled'} -</option>
1071                                                         <option value='daily' $selected{'AUTOUPDATE_INTERVAL'}{'daily'} >$Lang::tr{'Daily'}</option>
1072                                                         <option value='weekly' $selected{'AUTOUPDATE_INTERVAL'}{'weekly'} >$Lang::tr{'Weekly'}</option>
1073                                                 </select>
1074                                         </td>
1075                                 </tr>
1076                         </table>
1077
1078                         <br><br>
1079
1080                         <table width='100%'>
1081                                 <tr>
1082                                         <td align='right'><input type='submit' name='IDS' value='$Lang::tr{'save'}' /></td>
1083                                 </tr>
1084                         </table>
1085                 </form>
1086 END
1087 ;
1088
1089         }
1090
1091         &Header::closebox();
1092
1093         #
1094         # Used Ruleset Providers section.
1095         #
1096         &Header::openbox('100%', 'center', $Lang::tr{'ids ruleset settings'});
1097
1098 print <<END;
1099         <table width='100%' border='0'>
1100                 <tr>
1101                         <td class='base' bgcolor='$color{'color20'}'><b>$Lang::tr{'ids provider'}</b></td>
1102                         <td class='base' bgcolor='$color{'color20'}'><b>$Lang::tr{'date'}</b></td>
1103                         <td class='base' bgcolor='$color{'color20'}' align='center'><b>$Lang::tr{'ids autoupdates'}</b></td>
1104                         <td class='base' bgcolor='$color{'color20'}'></td>
1105                         <td class='base' colspan='3' bgcolor='$color{'color20'}'></td>
1106                 </tr>
1107 END
1108                 # Check if some providers has been configured.
1109                 if (keys (%used_providers)) {
1110                         my $col = "";
1111
1112                         # Loop through all entries of the hash.
1113                         foreach my $id (sort keys(%used_providers)) {
1114                                 # Assign data array positions to some nice variable names.
1115                                 my $provider = $used_providers{$id}[0];
1116                                 my $provider_name = &get_provider_name($provider);
1117
1118                                 #XXX my $rulesdate = &IDS::get_ruleset_date($provider);
1119                                 my $rulesdate;
1120
1121                                 my $subscription_code = $used_providers{$id}[1];
1122                                 my $autoupdate_status = $used_providers{$id}[2];
1123                                 my $status  = $used_providers{$id}[3];
1124
1125                                 # Check if the item number is even or not.
1126                                 if ($id % 2) {
1127                                         $col="bgcolor='$color{'color22'}'";
1128                                 } else {
1129                                         $col="bgcolor='$color{'color20'}'";
1130                                 }
1131
1132                                 # Choose icons for the checkboxes.
1133                                 my $status_gif;
1134                                 my $status_gdesc;
1135                                 my $autoupdate_status_gif;
1136                                 my $autoupdate_status_gdesc;
1137
1138                                 # Check if the status is enabled and select the correct image and description.
1139                                 if ($status eq 'enabled' ) {
1140                                         $status_gif = 'on.gif';
1141                                         $status_gdesc = $Lang::tr{'click to disable'};
1142                                 } else {
1143                                         $status_gif = 'off.gif';
1144                                         $status_gdesc = $Lang::tr{'click to enable'};
1145                                 }
1146
1147                                 # Check if the autoupdate status is enabled and select the correct image and description.
1148                                 if ($autoupdate_status eq 'enabled') {
1149                                         $autoupdate_status_gif = 'on.gif';
1150                                         $autoupdate_status_gdesc = $Lang::tr{'click to disable'};
1151                                 } else {
1152                                         $autoupdate_status_gif = 'off.gif';
1153                                         $autoupdate_status_gdesc = $Lang::tr{'click to enable'};
1154                                 }
1155
1156 print <<END;
1157                                 <tr>
1158                                         <td width='33%' class='base' $col>$provider_name</td>
1159                                         <td width='30%' class='base' $col>$rulesdate</td>
1160
1161                                         <td align='center' $col>
1162                                                 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
1163                                                         <input type='hidden' name='AUTOUPDATE' value='$Lang::tr{'toggle enable disable'}' />
1164                                                         <input type='image' name='$Lang::tr{'toggle enable disable'}' src='/images/$autoupdate_status_gif' alt='$autoupdate_status_gdesc' title='$autoupdate_status_gdesc' />
1165                                                         <input type='hidden' name='ID' value='$id' />
1166                                                 </form>
1167                                         </td>
1168
1169                                         <td align='center' $col>
1170                                                 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
1171                                                         <input type='hidden' name='PROVIDERS' value='$Lang::tr{'toggle enable disable'}'>
1172                                                         <input type='image' name='$Lang::tr{'toggle enable disable'}' src='/images/$status_gif' alt='$status_gdesc' title='$status_gdesc'>
1173                                                         <input type='hidden' name='ID' value='$id'>
1174                                                 </form>
1175                                         </td>
1176
1177                                         <td align='center' $col>
1178                                                 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
1179                                                         <input type='hidden' name='PROVIDERS' value='$Lang::tr{'edit'}'>
1180                                                         <input type='image' name='$Lang::tr{'edit'}' src='/images/edit.gif' alt='$Lang::tr{'edit'}' title='$Lang::tr{'edit'}'>
1181                                                         <input type='hidden' name='ID' value='$id'>
1182                                                 </form>
1183                                         </td>
1184
1185                                         <td align='center' $col>
1186                                                 <form method='post' name='$provider' action='$ENV{'SCRIPT_NAME'}'>
1187                                                         <input type='image' name='$Lang::tr{'remove'}' src='/images/delete.gif' title='$Lang::tr{'remove'}' alt='$Lang::tr{'remove'}'>
1188                                                         <input type='hidden' name='ID' value='$id'>
1189                                                         <input type='hidden' name='PROVIDERS' value='$Lang::tr{'remove'}'>
1190                                                 </form>
1191                                         </td>
1192                                 </tr>
1193 END
1194                         }
1195
1196                 } else {
1197                         # Print notice that currently no hosts are ignored.
1198                         print "<tr>\n";
1199                         print "<td class='base' colspan='2'>$Lang::tr{'guardian no entries'}</td>\n";
1200                         print "</tr>\n";
1201                 }
1202
1203         print "</table>\n";
1204
1205         # Section to add new elements or edit existing ones.
1206 print <<END;
1207         <br>
1208         <hr>
1209         <br>
1210
1211         <div align='right'>
1212                 <table width='100%'>
1213                         <form method='post' action='$ENV{'SCRIPT_NAME'}'>
1214                                 <tr>
1215 END
1216
1217                                         # Only show this button if a ruleset provider is configured.
1218                                         if (%used_providers) {
1219                                                 print "<input type='submit' name='RULESET' value='$Lang::tr{'ids customize ruleset'}'>\n";
1220                                         }
1221 print <<END;
1222                                         <input type='submit' name='PROVIDERS' value='$Lang::tr{'ids add provider'}'>
1223                                 </tr>
1224                         </form>
1225                 </table>
1226         </div>
1227 END
1228
1229         &Header::closebox();
1230
1231         #
1232         # Whitelist / Ignorelist
1233         #
1234         &Header::openbox('100%', 'center', $Lang::tr{'ids ignored hosts'});
1235
1236         print <<END;
1237         <table width='100%'>
1238                 <tr>
1239                         <td class='base' bgcolor='$color{'color20'}'><b>$Lang::tr{'ip address'}</b></td>
1240                         <td class='base' bgcolor='$color{'color20'}'><b>$Lang::tr{'remark'}</b></td>
1241                         <td class='base' colspan='3' bgcolor='$color{'color20'}'></td>
1242                 </tr>
1243 END
1244                 # Check if some hosts have been added to be ignored.
1245                 if (keys (%ignored)) {
1246                         my $col = "";
1247
1248                         # Loop through all entries of the hash.
1249                         while( (my $key) = each %ignored)  {
1250                                 # Assign data array positions to some nice variable names.
1251                                 my $address = $ignored{$key}[0];
1252                                 my $remark = $ignored{$key}[1];
1253                                 my $status  = $ignored{$key}[2];
1254
1255                                 # Check if the key (id) number is even or not.
1256                                 if ($cgiparams{'ID'} eq $key) {
1257                                         $col="bgcolor='${Header::colouryellow}'";
1258                                 } elsif ($key % 2) {
1259                                         $col="bgcolor='$color{'color22'}'";
1260                                 } else {
1261                                         $col="bgcolor='$color{'color20'}'";
1262                                 }
1263
1264                                 # Choose icon for the checkbox.
1265                                 my $gif;
1266                                 my $gdesc;
1267
1268                                 # Check if the status is enabled and select the correct image and description.
1269                                 if ($status eq 'enabled' ) {
1270                                         $gif = 'on.gif';
1271                                         $gdesc = $Lang::tr{'click to disable'};
1272                                 } else {
1273                                         $gif = 'off.gif';
1274                                         $gdesc = $Lang::tr{'click to enable'};
1275                                 }
1276
1277 print <<END;
1278                                 <tr>
1279                                         <td width='20%' class='base' $col>$address</td>
1280                                         <td width='65%' class='base' $col>$remark</td>
1281
1282                                         <td align='center' $col>
1283                                                 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
1284                                                         <input type='hidden' name='WHITELIST' value='$Lang::tr{'toggle enable disable'}'>
1285                                                         <input type='image' name='$Lang::tr{'toggle enable disable'}' src='/images/$gif' alt='$gdesc' title='$gdesc'>
1286                                                         <input type='hidden' name='ID' value='$key'>
1287                                                 </form>
1288                                         </td>
1289
1290                                         <td align='center' $col>
1291                                                 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
1292                                                         <input type='hidden' name='WHITELIST' value='$Lang::tr{'edit'}'>
1293                                                         <input type='image' name='$Lang::tr{'edit'}' src='/images/edit.gif' alt='$Lang::tr{'edit'}' title='$Lang::tr{'edit'}'>
1294                                                         <input type='hidden' name='ID' value='$key'>
1295                                                 </form>
1296                                         </td>
1297
1298                                         <td align='center' $col>
1299                                                 <form method='post' name='$key' action='$ENV{'SCRIPT_NAME'}'>
1300                                                         <input type='image' name='$Lang::tr{'remove'}' src='/images/delete.gif' title='$Lang::tr{'remove'}' alt='$Lang::tr{'remove'}'>
1301                                                         <input type='hidden' name='ID' value='$key'>
1302                                                         <input type='hidden' name='WHITELIST' value='$Lang::tr{'remove'}'>
1303                                                 </form>
1304                                                 </td>
1305                                         </tr>
1306 END
1307                                 }
1308                         } else {
1309                                 # Print notice that currently no hosts are ignored.
1310                                 print "<tr>\n";
1311                                 print "<td class='base' colspan='2'>$Lang::tr{'guardian no entries'}</td>\n";
1312                                 print "</tr>\n";
1313                         }
1314
1315                 print "</table>\n";
1316
1317                 # Section to add new elements or edit existing ones.
1318 print <<END;
1319                 <br>
1320                 <hr>
1321                 <br>
1322
1323                 <div align='center'>
1324                         <table width='100%'>
1325 END
1326
1327                 # Assign correct headline and button text.
1328                 my $buttontext;
1329                 my $entry_address;
1330                 my $entry_remark;
1331
1332                 # Check if an ID (key) has been given, in this case an existing entry should be edited.
1333                 if ($cgiparams{'ID'} ne '') {
1334                         $buttontext = $Lang::tr{'update'};
1335                                 print "<tr><td class='boldbase' colspan='3'><b>$Lang::tr{'update'}</b></td></tr>\n";
1336
1337                                 # Grab address and remark for the given key.
1338                                 $entry_address = $ignored{$cgiparams{'ID'}}[0];
1339                                 $entry_remark = $ignored{$cgiparams{'ID'}}[1];
1340                         } else {
1341                                 $buttontext = $Lang::tr{'add'};
1342                                 print "<tr><td class='boldbase' colspan='3'><b>$Lang::tr{'dnsforward add a new entry'}</b></td></tr>\n";
1343                         }
1344
1345 print <<END;
1346                                 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
1347                                 <input type='hidden' name='ID' value='$cgiparams{'ID'}'>
1348                                 <tr>
1349                                         <td width='30%'>$Lang::tr{'ip address'}: </td>
1350                                         <td width='50%'><input type='text' name='IGNORE_ENTRY_ADDRESS' value='$entry_address' size='24' /></td>
1351
1352                                         <td width='30%'>$Lang::tr{'remark'}: </td>
1353                                         <td wicth='50%'><input type='text' name=IGNORE_ENTRY_REMARK value='$entry_remark' size='24' /></td>
1354                                         <td align='center' width='20%'><input type='submit' name='WHITELIST' value='$buttontext' /></td>
1355                                 </tr>
1356                                 </form>
1357                         </table>
1358                 </div>
1359 END
1360
1361         &Header::closebox();
1362 }
1363
1364 #
1365 ## Function to show the customize ruleset section.
1366 #
1367 sub show_customize_ruleset() {
1368         ### Java Script ###
1369         print"<script>\n";
1370
1371         # Java script variable declaration for show and hide.
1372         print"var show = \"$Lang::tr{'ids show'}\"\;\n";
1373         print"var hide = \"$Lang::tr{'ids hide'}\"\;\n";
1374
1375 print <<END
1376         // Tiny java script function to show/hide the rules
1377         // of a given category.
1378         function showhide(tblname) {
1379                 \$("#" + tblname).toggle();
1380
1381                 // Get current content of the span element.
1382                 var content = document.getElementById("span_" + tblname);
1383
1384                 if (content.innerHTML === show) {
1385                         content.innerHTML = hide;
1386                 } else {
1387                         content.innerHTML = show;
1388                 }
1389         }
1390         </script>
1391 END
1392 ;
1393         &Header::openbox('100%', 'LEFT', "$Lang::tr{'intrusion detection system rules'}" );
1394                 print"<form method='POST' action='$ENV{'SCRIPT_NAME'}'>\n";
1395
1396                 # Output display table for rule files
1397                 print "<table width='100%'>\n";
1398
1399                 # Loop over each rule file
1400                 foreach my $rulefile (sort keys(%idsrules)) {
1401                         my $rulechecked = '';
1402
1403                         # Check if rule file is enabled
1404                         if ($idsrules{$rulefile}{'Rulefile'}{'State'} eq 'on') {
1405                                 $rulechecked = 'CHECKED';
1406                         }
1407
1408                         # Convert rulefile name into category name.
1409                         my $categoryname = &_rulefile_to_category($rulefile);
1410
1411                         # Table and rows for the rule files.
1412                         print"<tr>\n";
1413                         print"<td class='base' width='5%'>\n";
1414                         print"<input type='checkbox' name='$rulefile' $rulechecked>\n";
1415                         print"</td>\n";
1416                         print"<td class='base' width='90%'><b>$rulefile</b></td>\n";
1417                         print"<td class='base' width='5%' align='right'>\n";
1418                         print"<a href=\"javascript:showhide('$categoryname')\"><span id='span_$categoryname'>$Lang::tr{'ids show'}</span></a>\n";
1419                         print"</td>\n";
1420                         print"</tr>\n";
1421
1422                         # Rows which will be hidden per default and will contain the single rules.
1423                         print"<tr  style='display:none' id='$categoryname'>\n";
1424                         print"<td colspan='3'>\n";
1425
1426                         # Local vars
1427                         my $lines;
1428                         my $rows;
1429                         my $col;
1430
1431                         # New table for the single rules.
1432                         print "<table width='100%'>\n";
1433
1434                         # Loop over rule file rules
1435                         foreach my $sid (sort {$a <=> $b} keys(%{$idsrules{$rulefile}})) {
1436                                 # Local vars
1437                                 my $ruledefchecked = '';
1438
1439                                 # Skip rulefile itself.
1440                                 next if ($sid eq "Rulefile");
1441
1442                                 # If 2 rules have been displayed, start a new row
1443                                 if (($lines % 2) == 0) {
1444                                         print "</tr><tr>\n";
1445
1446                                         # Increase rows by once.
1447                                         $rows++;
1448                                 }
1449
1450                                 # Colour lines.
1451                                 if ($rows % 2) {
1452                                         $col="bgcolor='$color{'color20'}'";
1453                                 } else {
1454                                         $col="bgcolor='$color{'color22'}'";
1455                                 }
1456
1457                                 # Set rule state
1458                                 if ($idsrules{$rulefile}{$sid}{'State'} eq 'on') {
1459                                         $ruledefchecked = 'CHECKED';
1460                                 }
1461
1462                                 # Create rule checkbox and display rule description
1463                                 print "<td class='base' width='5%' align='right' $col>\n";
1464                                 print "<input type='checkbox' NAME='$sid' $ruledefchecked>\n";
1465                                 print "</td>\n";
1466                                 print "<td class='base' width='45%' $col>$idsrules{$rulefile}{$sid}{'Description'}</td>";
1467
1468                                 # Increment rule count
1469                                 $lines++;
1470                         }
1471
1472                         # If do not have a second rule for row, create empty cell
1473                         if (($lines % 2) != 0) {
1474                                 print "<td class='base'></td>";
1475                         }
1476
1477                         # Close display table
1478                         print "</tr></table></td></tr>";
1479                 }
1480
1481                 # Close display table
1482                 print "</table>";
1483
1484                 print <<END
1485 <table width='100%'>
1486 <tr>
1487         <td width='100%' align='right'>
1488                 <input type='submit' value='$Lang::tr{'fwhost back'}'>
1489                 <input type='submit' name='RULESET' value='$Lang::tr{'ids apply'}'>
1490         </td>
1491 </tr>
1492 </table>
1493 </form>
1494 END
1495 ;
1496                 &Header::closebox();
1497         }
1498 }
1499
1500 #
1501 ## Function to show section for add/edit a provider.
1502 #
1503 sub show_add_provider() {
1504         my %used_providers = ();
1505         my @subscription_providers;
1506
1507         # Read -in providers settings file.
1508         &General::readhasharray("$IDS::providers_settings_file", \%used_providers);
1509
1510         # Get all supported ruleset providers.
1511         my @ruleset_providers = &IDS::get_ruleset_providers();
1512
1513         ### Java Script ###
1514         print "<script>\n";
1515
1516         # Generate Java Script Object which contains the URL of the providers.
1517         print "\t// Object, which contains the webpages of the ruleset providers.\n";
1518         print "\tvar url = {\n";
1519
1520         # Loop through the array of supported providers.
1521         foreach my $provider (@ruleset_providers) {
1522                 # Check if the provider requires a subscription.
1523                 if ($IDS::Ruleset::Providers{$provider}{'requires_subscription'} eq "True") {
1524                         # Add the provider to the array of subscription_providers.
1525                         push(@subscription_providers, $provider);
1526                 }
1527
1528                 # Grab the URL for the provider.
1529                 my $url = $IDS::Ruleset::Providers{$provider}{'website'};
1530
1531                 # Print the URL to the Java Script Object.
1532                 print "\t\t$provider: \"$url\"\,\n";
1533         }
1534
1535         # Close the Java Script Object declaration.
1536         print "\t}\;\n\n";
1537
1538         # Generate Java Script Array which contains the provider that requires a subscription.
1539         my $line = "";
1540         $line = join("', '", @subscription_providers);
1541
1542         print "\t// Array which contains the providers that requires a subscription.\n";
1543         print "\tsubscription_provider = ['$line']\;\n\n";
1544
1545 print <<END
1546         // Java Script function to swap the text input field for
1547         // entering a subscription code.
1548         var update_provider = function() {
1549                 if(inArray(\$('#PROVIDER').val(), subscription_provider)) {
1550                         \$('.subscription_code').show();
1551                 } else {
1552                         \$('.subscription_code').hide();
1553                 }
1554
1555                 // Call function to change the website url.
1556                 change_url(\$('#PROVIDER').val());
1557         };
1558
1559         // Java Script function to check if a given value is part of
1560         // an array.
1561         function inArray(value,array) {
1562                 var count=array.length;
1563
1564                 for(var i=0;i<count;i++) {
1565                         if(array[i]===value){
1566                                 return true;
1567                         }
1568                 }
1569
1570                 return false;
1571         }
1572
1573         // Tiny function to change the website url based on the selected element in the "PROVIDERS"
1574         // dropdown menu.
1575         function change_url(provider) {
1576                 // Get and change the href to the corresponding url.
1577                 document.getElementById("website").href = url[provider];
1578         }
1579
1580         // JQuery function to call corresponding function when
1581         // the ruleset provider is changed or the page is loaded for showing/hiding
1582         // the subscription_code area.
1583         \$(document).ready(function() {
1584                 \$('#PROVIDER').change(update_provider);
1585                         update_provider();
1586         });
1587
1588         </script>
1589 END
1590 ;
1591
1592         &Header::openbox('100%', 'center', $Lang::tr{'ids provider settings'});
1593
1594         # Check if an existing provider should be edited.
1595         if($cgiparams{'PROVIDERS'} eq "$Lang::tr{'edit'}") {
1596                 # Check if autoupdate is enabled for this provider.
1597                 if ($used_providers{$cgiparams{'ID'}}[2] eq "enabled") {
1598                         # Set the checkbox to be checked.
1599                         $checked{'ENABLE_AUTOUPDATE'} = "checked='checked'";
1600                 }
1601         } elsif ($cgiparams{'PROVIDERS'} eq "$Lang::tr{'ids add provider'}") {
1602                 # Set the autoupdate to true as default.
1603                 $checked{'ENABLE_AUTOUPDATE'} = "checked='checked'";
1604         }
1605
1606 print <<END
1607         <form method='post' action='$ENV{'SCRIPT_NAME'}'>
1608                 <table width='100%' border='0'>
1609                         <tr>
1610                                 <td colspan='2'><b>$Lang::tr{'ids provider'}</b></td>
1611                         </tr>
1612
1613                         <tr>
1614                                 <td width='40%'>
1615                                         <input type='hidden' name='ID' value='$cgiparams{'ID'}'>
1616                                         <select name='PROVIDER' id='PROVIDER'>
1617 END
1618 ;
1619                                                 # Loop through the array of ruleset providers.
1620                                                 foreach my $provider (@ruleset_providers) {
1621                                                         # Get the provider name.
1622                                                         my $provider_name = &get_provider_name($provider);
1623
1624                                                         # Pre-select the provider if one is given.
1625                                                         if (($used_providers{$cgiparams{'ID'}}[0] eq "$provider") || ($cgiparams{'PROVIDER'} eq "$provider")) {
1626                                                                 $selected{$provider} = "selected='selected'";
1627                                                         }
1628
1629                                                         # Add the provider to the dropdown menu.
1630                                                         print "<option value='$provider' $selected{$provider}>$provider_name</option>\n";
1631                                                 }
1632 print <<END
1633                                         </select>
1634                                 </td>
1635
1636                                 <td width='60%'>
1637                                         <b><a id="website" target="_blank" href="#">$Lang::tr{'ids visit provider website'}</a></b>
1638                                 </td>
1639                         </tr>
1640
1641                         <tr>
1642                                 <td colspan='2'><br><br></td>
1643                         </tr>
1644
1645                         <tr class='subscription_code' style='display:none' id='subscription_code'>
1646                                 <td colspan='2'>
1647                                         <table border='0'>
1648                                                 <tr>
1649                                                         <td>
1650                                                                 <b>$Lang::tr{'subscription code'}</b>
1651                                                         </td>
1652                                                 </tr>
1653
1654                                                 <tr>
1655                                                         <td>
1656                                                                 <input type='text' size='40' name='SUBSCRIPTION_CODE' value='$used_providers{$cgiparams{'ID'}}[1]'>
1657                                                         </td>
1658                                                 </tr>
1659
1660                                                 <tr>
1661                                                         <td><br><br></td>
1662                                                 </tr>
1663                                         </table>
1664                                 </td>
1665                         </tr>
1666
1667                         <tr>
1668                                 <td colspan='2'>
1669                                         <input type='checkbox' name='ENABLE_AUTOUPDATE' $checked{'ENABLE_AUTOUPDATE'}>&nbsp;$Lang::tr{'ids enable automatic updates'}
1670                                 </td>
1671                         </tr>
1672
1673                         <tr>
1674                                 <td colspan='2' align='right'>
1675                                         <input type='submit' value='$Lang::tr{'back'}'>
1676 END
1677 ;
1678                                 # Check if a provider should be added or edited.
1679                                 if ($cgiparams{'PROVIDERS'} eq "$Lang::tr{'edit'}") {
1680                                         # Display button for updating the existing provider.
1681                                         print "<input type='submit' name='PROVIDERS' value='$Lang::tr{'update'}'>\n";
1682                                 } else {
1683                                         # Display button to add the new provider.
1684                                         print "<input type='submit' name='PROVIDERS' value='$Lang::tr{'add'}'>\n";
1685                                 }
1686 print <<END
1687                                 </td>
1688                         </tr>
1689                 </table>
1690         </form>
1691 END
1692 ;
1693         &Header::closebox();
1694 }
1695
1696 #
1697 ## A function to display a notice, to lock the webpage and
1698 ## tell the user which action currently will be performed.
1699 #
1700 sub working_notice ($) {
1701         my ($message) = @_;
1702
1703         &Header::openpage($Lang::tr{'intrusion detection system'}, 1, '');
1704         &Header::openbigbox('100%', 'left', '', $errormessage);
1705         &Header::openbox( 'Waiting', 1,);
1706                 print <<END;
1707                         <table>
1708                                 <tr>
1709                                         <td><img src='/images/indicator.gif' alt='$Lang::tr{'aktiv'}' /></td>
1710                                         <td>$message</td>
1711                                 </tr>
1712                         </table>
1713 END
1714         &Header::closebox();
1715         &Header::closebigbox();
1716         &Header::closepage();
1717 }
1718
1719 #
1720 ## A tiny function to perform a reload of the webpage after one second.
1721 #
1722 sub reload () {
1723         print "<meta http-equiv='refresh' content='1'>\n";
1724
1725         # Stop the script.
1726         exit;
1727 }
1728
1729 #
1730 ## Private function to read-in and parse rules of a given rulefile.
1731 #
1732 ## The given file will be read, parsed and all valid rules will be stored by ID,
1733 ## message/description and it's state in the idsrules hash.
1734 #
1735 sub readrulesfile ($) {
1736         my $rulefile = shift;
1737
1738         # Open rule file and read in contents
1739         open(RULEFILE, "$IDS::rulespath/$rulefile") or die "Unable to read $rulefile!";
1740
1741         # Store file content in an array.
1742         my @lines = <RULEFILE>;
1743
1744         # Close file.
1745         close(RULEFILE);
1746
1747         # Loop over rule file contents
1748         foreach my $line (@lines) {
1749                 # Remove whitespaces.
1750                 chomp $line;
1751
1752                 # Skip blank  lines.
1753                 next if ($line =~ /^\s*$/);
1754
1755                 # Local vars.
1756                 my $sid;
1757                 my $msg;
1758
1759                 # Gather rule sid and message from the ruleline.
1760                 if ($line =~ m/.*msg:\"(.*?)\"\; .* sid:(.*?); /) {
1761                         $msg = $1;
1762                         $sid = $2;
1763
1764                         # Check if a rule has been found.
1765                         if ($sid && $msg) {
1766                                 # Add rule to the idsrules hash.
1767                                 $idsrules{$rulefile}{$sid}{'Description'} = $msg;
1768
1769                                 # Grab status of the rule. Check if ruleline starts with a "dash".
1770                                 if ($line =~ /^\#/) {
1771                                         # If yes, the rule is disabled.
1772                                         $idsrules{$rulefile}{$sid}{'State'} = "off";
1773                                 } else {
1774                                         # Otherwise the rule is enabled.
1775                                         $idsrules{$rulefile}{$sid}{'State'} = "on";
1776                                 }
1777                         }
1778                 }
1779         }
1780 }
1781
1782 #
1783 ## Function to get the used memory of a given process-id.
1784 #
1785 sub get_memory_usage($) {
1786         my ($pid) = @_;
1787
1788         my $memory = 0;
1789
1790         # Try to open the status file for the given process-id on the pseudo
1791         # file system proc.
1792         if (open(FILE, "/proc/$pid/status")) {
1793                 # Loop through the entire file.
1794                 while (<FILE>) {
1795                         # Splitt current line content and store them into variables.
1796                         my ($key, $value) = split(":", $_, 2);
1797
1798                         # Check if the current key is the one which contains the memory usage.
1799                         # The wanted one is VmRSS which contains the Real-memory (resident set)
1800                         # of the entire process.
1801                         if ($key eq "VmRSS") {
1802                                 # Found the memory usage add it to the memory variable.
1803                                 $memory += $value;
1804
1805                                 # Break the loop.
1806                                 last;
1807                         }
1808                 }
1809
1810                 # Close file handle.
1811                 close(FILE);
1812
1813                 # Return memory usage.
1814                 return $memory;
1815         }
1816
1817         # If the file could not be open, return nothing.
1818         return;
1819 }
1820
1821 #
1822 ## Function to read-in the given enabled or disables sids file.
1823 #
1824 sub read_enabled_disabled_sids_file($) {
1825         my ($file) = @_;
1826
1827         # Temporary hash to store the sids and their state. It will be
1828         # returned at the end of this function.
1829         my %temphash;
1830
1831         # Open the given filename.
1832         open(FILE, "$file") or die "Could not open $file. $!\n";
1833
1834         # Loop through the file.
1835         while(<FILE>) {
1836                 # Remove newlines.
1837                 chomp $_;
1838
1839                 # Skip blank lines.
1840                 next if ($_ =~ /^\s*$/);
1841
1842                 # Skip coments.
1843                 next if ($_ =~ /^\#/);
1844
1845                 # Splitt line into sid and state part.
1846                 my ($state, $sid) = split(" ", $_);
1847
1848                 # Skip line if the sid is not numeric.
1849                 next unless ($sid =~ /\d+/ );
1850
1851                 # Check if the sid was enabled.
1852                 if ($state eq "enablesid") {
1853                         # Add the sid and its state as enabled to the temporary hash.
1854                         $temphash{$sid} = "enabled";
1855                 # Check if the sid was disabled.
1856                 } elsif ($state eq "disablesid") {
1857                         # Add the sid and its state as disabled to the temporary hash.
1858                         $temphash{$sid} = "disabled";
1859                 # Invalid state - skip the current sid and state.
1860                 } else {
1861                         next;
1862                 }
1863         }
1864
1865         # Close filehandle.
1866         close(FILE);
1867
1868         # Return the hash.
1869         return %temphash;
1870 }
1871
1872 #
1873 ## Function to get the provider name from the language file or providers file for a given handle.
1874 #
1875 sub get_provider_name($) {
1876         my ($handle) = @_;
1877         my $provider_name;
1878
1879         # Get the required translation string for the given provider handle.
1880         my $tr_string = $IDS::Ruleset::Providers{$handle}{'tr_string'};
1881
1882         # Check if the translation string is available in the language files.
1883         if ($Lang::tr{$tr_string}) {
1884                 # Use the translated string from the language file.
1885                 $provider_name = $Lang::tr{$tr_string};
1886         } else {
1887                 # Fallback and use the provider summary from the providers file.
1888                 $provider_name = $IDS::Ruleset::Providers{$handle}{'summary'};
1889         }
1890
1891         # Return the obtained provider name.
1892         return $provider_name;
1893 }
1894
1895 #
1896 ## Private function to convert a given rulefile to a category name.
1897 ## ( No file extension anymore and if the name contained a dot, it
1898 ## would be replaced by a underline sign.)
1899 #
1900 sub _rulefile_to_category($) {
1901         my ($filename) = @_;
1902
1903         # Splitt the filename into single chunks and store them in a
1904         # temorary array.
1905         my @parts = split(/\./, $filename);
1906
1907         # Return / Remove last element of the temporary array.
1908         # This removes the file extension.
1909         pop @parts;
1910
1911         # Join together the single elements of the temporary array.
1912         # If these are more than one, use a "underline" for joining.
1913         my $category = join '_', @parts;
1914
1915         # Return the converted filename.
1916         return $category;
1917 }