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