html/cgi-bin/ids.cgi

   1 #!/usr/bin/perl
   2 ###############################################################################
   3 #                                                                             #
   4 # IPFire.org - A linux based firewall                                         #
   5 # Copyright (C) 2007-2018  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 "${General::swroot}/ids-functions.pl";
  32
  33 my %color = ();
  34 my %mainsettings = ();
  35 my %idsrules = ();
  36 my %idssettings=();
  37 my %rulessettings=();
  38 my %rulesetsources = ();
  39 my %cgiparams=();
  40 my %checked=();
  41 my %selected=();
  42 my %ignored=();
  43
  44 # Read-in main settings, for language, theme and colors.
  45 &General::readhash("${General::swroot}/main/settings", \%mainsettings);
  46 &General::readhash("/srv/web/ipfire/html/themes/".$mainsettings{'THEME'}."/include/colors.txt", \%color);
  47
  48 # Get the available network zones, based on the config type of the system and store
  49 # the list of zones in an array.
  50 my @network_zones = &IDS::get_available_network_zones();
  51
  52 my $errormessage;
  53
  54 # Create files if they does not exist yet.
  55 &IDS::check_and_create_filelayout();
  56
  57 # Hash which contains the colour code of a network zone.
  58 my %colourhash = (
  59         'red' => $Header::colourred,
  60         'green' => $Header::colourgreen,
  61         'blue' => $Header::colourblue,
  62         'orange' => $Header::colourorange
  63 );
  64
  65 &Header::showhttpheaders();
  66
  67 #Get GUI values
  68 &Header::getcgihash(\%cgiparams);
  69
  70 ## Add/edit an entry to the ignore file.
  71 #
  72 if (($cgiparams{'WHITELIST'} eq $Lang::tr{'add'}) || ($cgiparams{'WHITELIST'} eq $Lang::tr{'update'})) {
  73
  74         # Check if any input has been performed.
  75         if ($cgiparams{'IGNORE_ENTRY_ADDRESS'} ne '') {
  76
  77                 # Check if the given input is no valid IP-address or IP-address with subnet, display an error message.
  78                 if ((!&General::validip($cgiparams{'IGNORE_ENTRY_ADDRESS'})) && (!&General::validipandmask($cgiparams{'IGNORE_ENTRY_ADDRESS'}))) {
  79                         $errormessage = "$Lang::tr{'guardian invalid address or subnet'}";
  80                 }
  81         } else {
  82                 $errormessage = "$Lang::tr{'guardian empty input'}";
  83         }
  84
  85         # Go further if there was no error.
  86         if ($errormessage eq '') {
  87                 my %ignored = ();
  88                 my $id;
  89                 my $status;
  90
  91                 # Assign hash values.
  92                 my $new_entry_address = $cgiparams{'IGNORE_ENTRY_ADDRESS'};
  93                 my $new_entry_remark = $cgiparams{'IGNORE_ENTRY_REMARK'};
  94
  95                 # Read-in ignoredfile.
  96                 &General::readhasharray($IDS::ignored_file, \%ignored);
  97
  98                 # Check if we should edit an existing entry and got an ID.
  99                 if (($cgiparams{'WHITELIST'} eq $Lang::tr{'update'}) && ($cgiparams{'ID'})) {
 100                         # Assin the provided id.
 101                         $id = $cgiparams{'ID'};
 102
 103                         # Undef the given ID.
 104                         undef($cgiparams{'ID'});
 105
 106                         # Grab the configured status of the corresponding entry.
 107                         $status = $ignored{$id}[2];
 108                 } else {
 109                         # Each newly added entry automatically should be enabled.
 110                         $status = "enabled";
 111
 112                         # Generate the ID for the new entry.
 113                         #
 114                         # Sort the keys by their ID and store them in an array.
 115                         my @keys = sort { $a <=> $b } keys %ignored;
 116
 117                         # Reverse the key array.
 118                         my @reversed = reverse(@keys);
 119
 120                         # Obtain the last used id.
 121                         my $last_id = @reversed[0];
 122
 123                         # Increase the last id by one and use it as id for the new entry.
 124                         $id = ++$last_id;
 125                 }
 126
 127                 # Add/Modify the entry to/in the ignored hash.
 128                 $ignored{$id} = ["$new_entry_address", "$new_entry_remark", "$status"];
 129
 130                 # Write the changed ignored hash to the ignored file.
 131                 &General::writehasharray($IDS::ignored_file, \%ignored);
 132
 133                 # Regenerate the ignore file.
 134                 &IDS::generate_ignore_file();
 135         }
 136
 137         # Check if the IDS is running.
 138         if(&IDS::ids_is_running()) {
 139                 # Call suricatactrl to perform a reload.
 140                 &IDS::call_suricatactrl("reload");
 141         }
 142
 143 ## Toggle Enabled/Disabled for an existing entry on the ignore list.
 144 #
 145
 146 } elsif ($cgiparams{'WHITELIST'} eq $Lang::tr{'toggle enable disable'}) {
 147         my %ignored = ();
 148
 149         # Only go further, if an ID has been passed.
 150         if ($cgiparams{'ID'}) {
 151                 # Assign the given ID.
 152                 my $id = $cgiparams{'ID'};
 153
 154                 # Undef the given ID.
 155                 undef($cgiparams{'ID'});
 156
 157                 # Read-in ignoredfile.
 158                 &General::readhasharray($IDS::ignored_file, \%ignored);
 159
 160                 # Grab the configured status of the corresponding entry.
 161                 my $status = $ignored{$id}[2];
 162
 163                 # Switch the status.
 164                 if ($status eq "disabled") {
 165                         $status = "enabled";
 166                 } else {
 167                         $status = "disabled";
 168                 }
 169
 170                 # Modify the status of the existing entry.
 171                 $ignored{$id} = ["$ignored{$id}[0]", "$ignored{$id}[1]", "$status"];
 172
 173                 # Write the changed ignored hash to the ignored file.
 174                 &General::writehasharray($IDS::ignored_file, \%ignored);
 175
 176                 # Regenerate the ignore file.
 177                 &IDS::generate_ignore_file();
 178
 179                 # Check if the IDS is running.
 180                 if(&IDS::ids_is_running()) {
 181                         # Call suricatactrl to perform a reload.
 182                         &IDS::call_suricatactrl("reload");
 183                 }
 184         }
 185
 186 ## Remove entry from ignore list.
 187 #
 188 } elsif ($cgiparams{'WHITELIST'} eq $Lang::tr{'remove'}) {
 189         my %ignored = ();
 190
 191         # Read-in ignoredfile.
 192         &General::readhasharray($IDS::ignored_file, \%ignored);
 193
 194         # Drop entry from the hash.
 195         delete($ignored{$cgiparams{'ID'}});
 196
 197         # Undef the given ID.
 198         undef($cgiparams{'ID'});
 199
 200         # Write the changed ignored hash to the ignored file.
 201         &General::writehasharray($IDS::ignored_file, \%ignored);
 202
 203         # Regenerate the ignore file.
 204         &IDS::generate_ignore_file();
 205
 206         # Check if the IDS is running.
 207         if(&IDS::ids_is_running()) {
 208                 # Call suricatactrl to perform a reload.
 209                 &IDS::call_suricatactrl("reload");
 210         }
 211 }
 212
 213 # Check if any error has been stored.
 214 if (-e $IDS::storederrorfile) {
 215         # Open file to read in the stored error message.
 216         open(FILE, "<$IDS::storederrorfile") or die "Could not open $IDS::storederrorfile. $!\n";
 217
 218         # Read the stored error message.
 219         $errormessage = <FILE>;
 220
 221         # Close file.
 222         close (FILE);
 223
 224         # Delete the file, which is now not longer required.
 225         unlink($IDS::storederrorfile);
 226 }
 227
 228 ## Grab all available snort rules and store them in the idsrules hash.
 229 #
 230 # Open snort rules directory and do a directory listing.
 231 opendir(DIR, $IDS::rulespath) or die $!;
 232         # Loop through the direcory.
 233         while (my $file = readdir(DIR)) {
 234
 235                 # We only want files.
 236                 next unless (-f "$IDS::rulespath/$file");
 237
 238                 # Ignore empty files.
 239                 next if (-z "$IDS::rulespath/$file");
 240
 241                 # Use a regular expression to find files ending in .rules
 242                 next unless ($file =~ m/\.rules$/);
 243
 244                 # Ignore files which are not read-able.
 245                 next unless (-R "$IDS::rulespath/$file");
 246
 247                 # Skip whitelist rules file.
 248                 next if( $file eq "whitelist.rules");
 249
 250                 # Call subfunction to read-in rulefile and add rules to
 251                 # the idsrules hash.
 252                 &readrulesfile("$file");
 253         }
 254
 255 closedir(DIR);
 256
 257 # Gather used rulefiles.
 258 #
 259 # Check if the file for activated rulefiles is not empty.
 260 if(-f $IDS::used_rulefiles_file) {
 261         # Open the file for used rulefile and read-in content.
 262         open(FILE, $IDS::used_rulefiles_file) or die "Could not open $IDS::used_rulefiles_file. $!\n";
 263
 264         # Read-in content.
 265         my @lines = <FILE>;
 266
 267         # Close file.
 268         close(FILE);
 269
 270         # Loop through the array.
 271         foreach my $line (@lines) {
 272                 # Remove newlines.
 273                 chomp($line);
 274
 275                 # Skip comments.
 276                 next if ($line =~ /\#/);
 277
 278                 # Skip blank  lines.
 279                 next if ($line =~ /^\s*$/);
 280
 281                 # Gather rule sid and message from the ruleline.
 282                 if ($line =~ /.*- (.*)/) {
 283                         my $rulefile = $1;
 284
 285                         # Check if the current rulefile exists in the %idsrules hash.
 286                         # If not, the file probably does not exist anymore or contains
 287                         # no rules.
 288                         if($idsrules{$rulefile}) {
 289                                 # Add the rulefile state to the %idsrules hash.
 290                                 $idsrules{$rulefile}{'Rulefile'}{'State'} = "on";
 291                         }
 292                 }
 293         }
 294 }
 295
 296 # Save ruleset configuration.
 297 if ($cgiparams{'RULESET'} eq $Lang::tr{'save'}) {
 298         my %oldsettings;
 299
 300         # Read-in current (old) IDS settings.
 301         &General::readhash("$IDS::rules_settings_file", \%oldsettings);
 302
 303         # Prevent form name from been stored in conf file.
 304         delete $cgiparams{'RULESET'};
 305
 306         # Check if an oinkcode has been provided.
 307         if ($cgiparams{'OINKCODE'}) {
 308                 # Check if the oinkcode contains unallowed chars.
 309                 unless ($cgiparams{'OINKCODE'} =~ /^[a-z0-9]+$/) {
 310                         $errormessage = $Lang::tr{'invalid input for oink code'};
 311                 }
 312         }
 313
 314         # Go on if there are no error messages.
 315         if (!$errormessage) {
 316                 # Store settings into settings file.
 317                 &General::writehash("$IDS::rules_settings_file", \%cgiparams);
 318         }
 319
 320         # Check if the the automatic rule update hass been touched.
 321         if($cgiparams{'AUTOUPDATE_INTERVAL'} ne $oldsettings{'AUTOUPDATE_INTERVAL'}) {
 322                 # Call suricatactrl to set the new interval.
 323                 &IDS::call_suricatactrl("cron", $cgiparams{'AUTOUPDATE_INTERVAL'});
 324         }
 325
 326 # Save ruleset.
 327 } elsif ($cgiparams{'RULESET'} eq $Lang::tr{'update'}) {
 328         # Arrays to store which rulefiles have been enabled and will be used.
 329         my @enabled_rulefiles;
 330
 331         # Hash to store the user-enabled and disabled sids.
 332         my %enabled_disabled_sids;
 333
 334         # Loop through the hash of idsrules.
 335         foreach my $rulefile(keys %idsrules) {
 336                 # Check if the rulefile is enabled.
 337                 if ($cgiparams{$rulefile} eq "on") {
 338                         # Add rulefile to the array of enabled rulefiles.
 339                         push(@enabled_rulefiles, $rulefile);
 340
 341                         # Drop item from cgiparams hash.
 342                         delete $cgiparams{$rulefile};
 343                 }
 344         }
 345
 346         # Read-in the files for enabled/disabled sids.
 347         # This will be done by calling the read_enabled_disabled_sids_file function two times
 348         # and merge the returned hashes together into the enabled_disabled_sids hash.
 349         %enabled_disabled_sids = (
 350                 &read_enabled_disabled_sids_file($IDS::disabled_sids_file),
 351                 &read_enabled_disabled_sids_file($IDS::enabled_sids_file));
 352
 353         # Loop through the hash of idsrules.
 354         foreach my $rulefile (keys %idsrules) {
 355                 # Loop through the single rules of the rulefile.
 356                 foreach my $sid (keys %{$idsrules{$rulefile}}) {
 357                         # Skip the current sid if it is not numeric.
 358                         next unless ($sid =~ /\d+/ );
 359
 360                         # Check if there exists a key in the cgiparams hash for this sid.
 361                         if (exists($cgiparams{$sid})) {
 362                                 # Look if the rule is disabled.
 363                                 if ($idsrules{$rulefile}{$sid}{'State'} eq "off") {
 364                                         # Check if the state has been set to 'on'.
 365                                         if ($cgiparams{$sid} eq "on") {
 366                                                 # Add/Modify the sid to/in the enabled_disabled_sids hash.
 367                                                 $enabled_disabled_sids{$sid} = "enabled";
 368
 369                                                 # Drop item from cgiparams hash.
 370                                                 delete $cgiparams{$rulefile}{$sid};
 371                                         }
 372                                 }
 373                         } else {
 374                                 # Look if the rule is enabled.
 375                                 if ($idsrules{$rulefile}{$sid}{'State'} eq "on") {
 376                                         # Check if the state is 'on' and should be disabled.
 377                                         # In this case there is no entry
 378                                         # for the sid in the cgiparams hash.
 379                                         # Add/Modify it to/in the enabled_disabled_sids hash.
 380                                         $enabled_disabled_sids{$sid} = "disabled";
 381
 382                                         # Drop item from cgiparams hash.
 383                                         delete $cgiparams{$rulefile}{$sid};
 384                                 }
 385                         }
 386                 }
 387         }
 388
 389         # Open enabled sid's file for writing.
 390         open(ENABLED_FILE, ">$IDS::enabled_sids_file") or die "Could not write to $IDS::enabled_sids_file. $!\n";
 391
 392         # Open disabled sid's file for writing.
 393         open(DISABLED_FILE, ">$IDS::disabled_sids_file") or die "Could not write to $IDS::disabled_sids_file. $!\n";
 394
 395         # Write header to the files.
 396         print ENABLED_FILE "#Autogenerated file. Any custom changes will be overwritten!\n";
 397         print DISABLED_FILE "#Autogenerated file. Any custom changes will be overwritten!\n";
 398
 399         # Check if the hash for enabled/disabled files contains any entries.
 400         if (%enabled_disabled_sids) {
 401                 # Loop through the hash.
 402                 foreach my $sid (keys %enabled_disabled_sids) {
 403                         # Check if the sid is enabled.
 404                         if ($enabled_disabled_sids{$sid} eq "enabled") {
 405                                 # Print the sid to the enabled_sids file.
 406                                 print ENABLED_FILE "enablesid $sid\n";
 407                         # Check if the sid is disabled.
 408                         } elsif ($enabled_disabled_sids{$sid} eq "disabled") {
 409                                 # Print the sid to the disabled_sids file.
 410                                 print DISABLED_FILE "disablesid $sid\n";
 411                         # Something strange happende - skip the current sid.
 412                         } else {
 413                                 next;
 414                         }
 415                 }
 416         }
 417
 418         # Close file for enabled_sids after writing.
 419         close(ENABLED_FILE);
 420
 421         # Close file for disabled_sids after writing.
 422         close(DISABLED_FILE);
 423
 424         # Call function to generate and write the used rulefiles file.
 425         &IDS::write_used_rulefiles_file(@enabled_rulefiles);
 426
 427         # Lock the webpage and print message.
 428         &working_notice("$Lang::tr{'snort working'}");
 429
 430         # Call oinkmaster to alter the ruleset.
 431         &IDS::oinkmaster();
 432
 433         # Check if the IDS is running.
 434         if(&IDS::ids_is_running()) {
 435                 # Call suricatactrl to perform a reload.
 436                 &IDS::call_suricatactrl("reload");
 437         }
 438
 439         # Reload page.
 440         &reload();
 441
 442 # Download new ruleset.
 443 } elsif ($cgiparams{'RULESET'} eq $Lang::tr{'download new ruleset'}) {
 444         # Check if the red device is active.
 445         unless (-e "${General::swroot}/red/active") {
 446                 $errormessage = $Lang::tr{'could not download latest updates'};
 447         }
 448
 449         # Check if enought free disk space is availabe.
 450         if(&IDS::checkdiskspace()) {
 451                 $errormessage = "$Lang::tr{'not enough disk space'}";
 452         }
 453
 454         # Check if any errors happend.
 455         unless ($errormessage) {
 456                 # Lock the webpage and print notice about downloading
 457                 # a new ruleset.
 458                 &working_notice("$Lang::tr{'snort working'}");
 459
 460                 # Call subfunction to download the ruleset.
 461                 if(&IDS::downloadruleset()) {
 462                         $errormessage = $Lang::tr{'could not download latest updates'};
 463
 464                         # Call function to store the errormessage.
 465                         &IDS::_store_error_message($errormessage);
 466
 467                         # Preform a reload of the page.
 468                         &reload();
 469                 } else {
 470                         # Call subfunction to launch oinkmaster.
 471                         &IDS::oinkmaster();
 472
 473                         # Check if the IDS is running.
 474                         if(&IDS::ids_is_running()) {
 475                                 # Call suricatactrl to perform a reload.
 476                                 &IDS::call_suricatactrl("reload");
 477                         }
 478
 479                         # Perform a reload of the page.
 480                         &reload();
 481                 }
 482         }
 483 # Save snort settings.
 484 } elsif ($cgiparams{'IDS'} eq $Lang::tr{'save'}) {
 485         my %oldidssettings;
 486         my $reload_page;
 487         my $monitored_zones = 0;
 488
 489         # Read-in current (old) IDS settings.
 490         &General::readhash("$IDS::ids_settings_file", \%oldidssettings);
 491
 492         # Prevent form name from been stored in conf file.
 493         delete $cgiparams{'IDS'};
 494
 495         # Check if the IDS should be enabled.
 496         if ($cgiparams{'ENABLE_IDS'} eq "on") {
 497                 # Check if any ruleset is available. Otherwise abort and display an error.
 498                 unless(%idsrules) {
 499                         $errormessage = $Lang::tr{'ids no ruleset available'};
 500                 }
 501
 502                 # Loop through the array of available interfaces.
 503                 foreach my $zone (@network_zones) {
 504                         # Convert interface name into upper case.
 505                         my $zone_upper = uc($zone);
 506
 507                         # Check if the IDS is enabled for this interaces.
 508                         if ($cgiparams{"ENABLE_IDS_$zone_upper"}) {
 509                                 # Increase count.
 510                                 $monitored_zones++;
 511                         }
 512                 }
 513
 514                 # Check if at least one zone should be monitored, or show an error.
 515                 unless ($monitored_zones >= 1) {
 516                         $errormessage = $Lang::tr{'ids no network zone'};
 517                 }
 518         }
 519
 520         # Go on if there are no error messages.
 521         if (!$errormessage) {
 522                 # Store settings into settings file.
 523                 &General::writehash("$IDS::ids_settings_file", \%cgiparams);
 524         }
 525
 526         # Generate file to store the home net.
 527         &IDS::generate_home_net_file();
 528
 529         # Temporary variable to set the ruleaction.
 530         # Default is "drop" to use suricata as IPS.
 531         my $ruleaction="drop";
 532
 533         # Check if the traffic only should be monitored.
 534         if($cgiparams{'MONITOR_TRAFFIC_ONLY'} eq 'on') {
 535                 # Switch the ruleaction to "alert".
 536                 # Suricata acts as an IDS only.
 537                 $ruleaction="alert";
 538         }
 539
 540         # Write the modify sid's file and pass the taken ruleaction.
 541         &IDS::write_modify_sids_file($ruleaction);
 542
 543         # Check if "MONITOR_TRAFFIC_ONLY" has been changed.
 544         if($cgiparams{'MONITOR_TRAFFIC_ONLY'} ne $oldidssettings{'MONITOR_TRAFFIC_ONLY'}) {
 545                 # Check if a ruleset exists.
 546                 if (%idsrules) {
 547                         # Lock the webpage and print message.
 548                         &working_notice("$Lang::tr{'snort working'}");
 549
 550                         # Call oinkmaster to alter the ruleset.
 551                         &IDS::oinkmaster();
 552
 553                         # Set reload_page to "True".
 554                         $reload_page="True";
 555                 }
 556         }
 557
 558         # Check if the IDS currently is running.
 559         if(&IDS::ids_is_running()) {
 560                 # Check if ENABLE_IDS is set to on.
 561                 if($cgiparams{'ENABLE_IDS'} eq "on") {
 562                         # Call suricatactrl to perform a reload of suricata.
 563                         &IDS::call_suricatactrl("reload");
 564                 } else {
 565                         # Call suricatactrl to stop suricata.
 566                         &IDS::call_suricatactrl("stop");
 567                 }
 568         } else {
 569                 # Call suricatactrl to start suricata.
 570                 &IDS::call_suricatactrl("start");
 571         }
 572
 573         # Check if the page should be reloaded.
 574         if ($reload_page) {
 575                 # Perform a reload of the page.
 576                 &reload();
 577         }
 578 }
 579
 580 # Read-in idssettings and rulesetsettings
 581 &General::readhash("$IDS::ids_settings_file", \%idssettings);
 582 &General::readhash("$IDS::rules_settings_file", \%rulessettings);
 583
 584 # If no autoupdate intervall has been configured yet, set default value.
 585 unless(exists($rulessettings{'AUTOUPDATE_INTERVAL'})) {
 586         # Set default to "weekly".
 587         $rulessettings{'AUTOUPDATE_INTERVAL'} = 'weekly';
 588 }
 589
 590 # Read-in ignored hosts.
 591 &General::readhasharray("$IDS::settingsdir/ignored", \%ignored);
 592
 593 $checked{'ENABLE_IDS'}{'off'} = '';
 594 $checked{'ENABLE_IDS'}{'on'} = '';
 595 $checked{'ENABLE_IDS'}{$idssettings{'ENABLE_IDS'}} = "checked='checked'";
 596 $checked{'MONITOR_TRAFFIC_ONLY'}{'off'} = '';
 597 $checked{'MONITOR_TRAFFIC_ONLY'}{'on'} = '';
 598 $checked{'MONITOR_TRAFFIC_ONLY'}{$idssettings{'MONITOR_TRAFFIC_ONLY'}} = "checked='checked'";
 599 $selected{'RULES'}{'nothing'} = '';
 600 $selected{'RULES'}{'community'} = '';
 601 $selected{'RULES'}{'emerging'} = '';
 602 $selected{'RULES'}{'registered'} = '';
 603 $selected{'RULES'}{'subscripted'} = '';
 604 $selected{'RULES'}{$rulessettings{'RULES'}} = "selected='selected'";
 605 $selected{'AUTOUPDATE_INTERVAL'}{'off'} = '';
 606 $selected{'AUTOUPDATE_INTERVAL'}{'daily'} = '';
 607 $selected{'AUTOUPDATE_INTERVAL'}{'weekly'} = '';
 608 $selected{'AUTOUPDATE_INTERVAL'}{$rulessettings{'AUTOUPDATE_INTERVAL'}} = "selected='selected'";
 609
 610 &Header::openpage($Lang::tr{'intrusion detection system'}, 1, '');
 611
 612 ### Java Script ###
 613 print <<END
 614 <script>
 615         // JQuery function to show/hide the text input field for
 616         // Oinkcode/Subscription code.
 617         \$(function() {
 618                 \$('#RULES').change(function(){
 619                         if(\$('#RULES').val() == 'registered') {
 620                                 \$('#code').show();
 621                         } else if(\$('#RULES').val() == 'subscripted') {
 622                                 \$('#code').show();
 623                         } else if(\$('#RULES').val() == 'emerging_pro') {
 624                                 \$('#code').show();
 625                         } else {
 626                                 \$('#code').hide();
 627                         }
 628                 });
 629         });
 630
 631         // Tiny java script function to show/hide the rules
 632         // of a given category.
 633         function showhide(tblname) {
 634                 \$("#" + tblname).toggle();
 635         }
 636 </script>
 637 END
 638 ;
 639
 640 &Header::openbigbox('100%', 'left', '', $errormessage);
 641
 642 if ($errormessage) {
 643         &Header::openbox('100%', 'left', $Lang::tr{'error messages'});
 644         print "<class name='base'>$errormessage\n";
 645         print "&nbsp;</class>\n";
 646         &Header::closebox();
 647 }
 648
 649 # Draw current state of the IDS
 650 &Header::openbox('100%', 'left', $Lang::tr{'intrusion detection system'});
 651
 652 # Check if the IDS is running and obtain the process-id.
 653 my $pid = &IDS::ids_is_running();
 654
 655 # Display some useful information, if suricata daemon is running.
 656 if ($pid) {
 657         # Gather used memory.
 658         my $memory = &get_memory_usage($pid);
 659
 660         print <<END;
 661                 <table width='95%' cellspacing='0' class='tbl'>
 662                         <tr>
 663                                 <th bgcolor='$color{'color20'}' colspan='3' align='left'><strong>$Lang::tr{'intrusion detection'}</strong></th>
 664                         </tr>
 665
 666                         <tr>
 667                                 <td class='base'>$Lang::tr{'guardian daemon'}</td>
 668                                 <td align='center' colspan='2' width='75%' bgcolor='${Header::colourgreen}'><font color='white'><strong>$Lang::tr{'running'}</strong></font></td>
 669                         </tr>
 670
 671                         <tr>
 672                                 <td class='base'></td>
 673                                 <td bgcolor='$color{'color20'}' align='center'><strong>PID</strong></td>
 674                                 <td bgcolor='$color{'color20'}' align='center'><strong>$Lang::tr{'memory'}</strong></td>
 675                         </tr>
 676
 677                         <tr>
 678                                 <td class='base'></td>
 679                                 <td bgcolor='$color{'color22'}' align='center'>$pid</td>
 680                                 <td bgcolor='$color{'color22'}' align='center'>$memory KB</td>
 681                         </tr>
 682                 </table>
 683 END
 684 } else {
 685         # Otherwise display a hint that the service is not launched.
 686         print <<END;
 687                 <table width='95%' cellspacing='0' class='tbl'>
 688                         <tr>
 689                                 <th bgcolor='$color{'color20'}' colspan='3' align='left'><strong>$Lang::tr{'intrusion detection'}</strong></th>
 690                         </tr>
 691
 692                         <tr>
 693                                 <td class='base'>$Lang::tr{'guardian daemon'}</td>
 694                                 <td align='center' width='75%' bgcolor='${Header::colourred}'><font color='white'><strong>$Lang::tr{'stopped'}</strong></font></td>
 695                         </tr>
 696                 </table>
 697 END
 698 }
 699
 700 my $rulesdate;
 701
 702 # Check if a ruleset allready has been downloaded.
 703 if ( -f "$IDS::rulestarball"){
 704         # Call stat on the filename to obtain detailed information.
 705         my @Info = stat("$IDS::rulestarball");
 706
 707         # Grab details about the creation time.
 708         $rulesdate = localtime($Info[9]);
 709 }
 710
 711 print <<END
 712
 713 <br><br><h2>$Lang::tr{'settings'}</h2>
 714
 715 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
 716         <table width='100%' border='0'>
 717                 <tr>
 718                         <td class='base' colspan='2'>
 719                                 <input type='checkbox' name='ENABLE_IDS' $checked{'ENABLE_IDS'}{'on'}>$Lang::tr{'ids activate'} $Lang::tr{'intrusion detection system'}
 720                         </td>
 721
 722                         <td class='base' colspan='2'>
 723                                 <input type='checkbox' name='MONITOR_TRAFFIC_ONLY' $checked{'MONITOR_TRAFFIC_ONLY'}{'on'}>$Lang::tr{'ids monitor traffic only'}
 724                         </td>
 725                 </tr>
 726
 727                 <tr>
 728                         <td><br><br></td>
 729                         <td><br><br></td>
 730                         <td><br><br></td>
 731                         <td><br><br></td>
 732                 </tr>
 733
 734                 <tr>
 735                         <td colspan='4'><b>$Lang::tr{'ids monitored interfaces'}</b><br></td>
 736                 </tr>
 737
 738                 <tr>
 739 END
 740 ;
 741
 742 # Loop through the array of available networks and print config options.
 743 foreach my $zone (@network_zones) {
 744         my $checked_input;
 745         my $checked_forward;
 746
 747         # Convert current zone name to upper case.
 748         my $zone_upper = uc($zone);
 749
 750         # Set zone name.
 751         my $zone_name = $zone;
 752
 753         # Dirty hack to get the correct language string for the red zone.
 754         if ($zone eq "red") {
 755                 $zone_name = "red1";
 756         }
 757
 758         # Grab checkbox status from settings hash.
 759         if ($idssettings{"ENABLE_IDS_$zone_upper"} eq "on") {
 760                 $checked_input = "checked = 'checked'";
 761         }
 762
 763         print "<td class='base' width='25%'>\n";
 764         print "<input type='checkbox' name='ENABLE_IDS_$zone_upper' $checked_input>\n";
 765         print "&nbsp$Lang::tr{'enabled on'}<font color='$colourhash{$zone}'> $Lang::tr{$zone_name}</font>\n";
 766         print "</td>\n";
 767 }
 768
 769 print <<END
 770                 </tr>
 771         </table>
 772
 773         <br><br>
 774
 775         <table width='100%'>
 776                 <tr>
 777                         <td align='right'><input type='submit' name='IDS' value='$Lang::tr{'save'}' /></td>
 778                 </tr>
 779         </table>
 780 </form>
 781 END
 782 ;
 783
 784 &Header::closebox();
 785
 786 # Draw elements for ruleset configuration.
 787 &Header::openbox('100%', 'center', $Lang::tr{'ids ruleset settings'});
 788
 789 print <<END
 790 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
 791         <table width='100%' border='0'>
 792                 <tr>
 793                         <td><b>$Lang::tr{'ids rules update'}</b></td>
 794                         <td><b>$Lang::tr{'ids automatic rules update'}</b></td>
 795                 </tr>
 796
 797                 <tr>
 798                         <td><select name='RULES' id='RULES'>
 799                                 <option value='emerging' $selected{'RULES'}{'emerging'} >$Lang::tr{'emerging rules'}</option>
 800                                 <option value='emerging_pro' $selected{'RULES'}{'emerging_pro'} >$Lang::tr{'emerging pro rules'}</option>
 801                                 <option value='community' $selected{'RULES'}{'community'} >$Lang::tr{'community rules'}</option>
 802                                 <option value='registered' $selected{'RULES'}{'registered'} >$Lang::tr{'registered user rules'}</option>
 803                                 <option value='subscripted' $selected{'RULES'}{'subscripted'} >$Lang::tr{'subscripted user rules'}</option>
 804                         </select>
 805                         </td>
 806
 807                         <td>
 808                                 <select name='AUTOUPDATE_INTERVAL'>
 809                                         <option value='off' $selected{'AUTOUPDATE_INTERVAL'}{'off'} >$Lang::tr{'no'}</option>
 810                                         <option value='daily' $selected{'AUTOUPDATE_INTERVAL'}{'daily'} >$Lang::tr{'urlfilter daily'}</option>
 811                                         <option value='weekly' $selected{'AUTOUPDATE_INTERVAL'}{'weekly'} >$Lang::tr{'urlfilter weekly'}</option>
 812                                 </select>
 813                         </td>
 814                 </tr>
 815
 816                 <tr>
 817                         <td colspan='2'><br><br></td>
 818                 </tr>
 819
 820                 <tr style='display:none' id='code'>
 821                         <td colspan='2'>Oinkcode:&nbsp;<input type='text' size='40' name='OINKCODE' value='$rulessettings{'OINKCODE'}'></td>
 822                 </tr>
 823
 824                 <tr>
 825                         <td>&nbsp;</td>
 826
 827                         <td align='right'>
 828 END
 829 ;
 830                         # Check if a ruleset has been downloaded yet.
 831                         if (%idsrules) {
 832                                 # Display button to update the ruleset.
 833                                 print"<input type='submit' name='RULESET' value='$Lang::tr{'update ruleset'}'>\n";
 834                 }
 835 print <<END;
 836                                 <input type='submit' name='RULESET' value='$Lang::tr{'save'}'>
 837                         </td>
 838
 839                 </tr>
 840         </table>
 841 </form>
 842 END
 843 ;
 844
 845 &Header::closebox();
 846
 847 #
 848 # Whitelist / Ignorelist
 849 #
 850 &Header::openbox('100%', 'center', $Lang::tr{'guardian ignored hosts'});
 851
 852 print <<END;
 853         <table width='100%'>
 854                 <tr>
 855                         <td class='base' bgcolor='$color{'color20'}'><b>$Lang::tr{'ip address'}</b></td>
 856                         <td class='base' bgcolor='$color{'color20'}'><b>$Lang::tr{'remark'}</b></td>
 857                         <td class='base' colspan='3' bgcolor='$color{'color20'}'></td>
 858                 </tr>
 859 END
 860                 # Check if some hosts have been added to be ignored.
 861                 if (keys (%ignored)) {
 862                         my $col = "";
 863
 864                         # Loop through all entries of the hash.
 865                         while( (my $key) = each %ignored)  {
 866                                 # Assign data array positions to some nice variable names.
 867                                 my $address = $ignored{$key}[0];
 868                                 my $remark = $ignored{$key}[1];
 869                                 my $status  = $ignored{$key}[2];
 870
 871                                 # Check if the key (id) number is even or not.
 872                                 if ($cgiparams{'ID'} eq $key) {
 873                                         $col="bgcolor='${Header::colouryellow}'";
 874                                 } elsif ($key % 2) {
 875                                         $col="bgcolor='$color{'color22'}'";
 876                                 } else {
 877                                         $col="bgcolor='$color{'color20'}'";
 878                                 }
 879
 880                                 # Choose icon for the checkbox.
 881                                 my $gif;
 882                                 my $gdesc;
 883
 884                                 # Check if the status is enabled and select the correct image and description.
 885                                 if ($status eq 'enabled' ) {
 886                                         $gif = 'on.gif';
 887                                         $gdesc = $Lang::tr{'click to disable'};
 888                                 } else {
 889                                         $gif = 'off.gif';
 890                                         $gdesc = $Lang::tr{'click to enable'};
 891                                 }
 892
 893 print <<END;
 894                                 <tr>
 895                                         <td width='20%' class='base' $col>$address</td>
 896                                         <td width='65%' class='base' $col>$remark</td>
 897
 898                                         <td align='center' $col>
 899                                                 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
 900                                                         <input type='hidden' name='WHITELIST' value='$Lang::tr{'toggle enable disable'}' />
 901                                                         <input type='image' name='$Lang::tr{'toggle enable disable'}' src='/images/$gif' alt='$gdesc' title='$gdesc' />
 902                                                         <input type='hidden' name='ID' value='$key' />
 903                                                 </form>
 904                                         </td>
 905
 906                                         <td align='center' $col>
 907                                                 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
 908                                                         <input type='hidden' name='WHITELIST' value='$Lang::tr{'edit'}' />
 909                                                         <input type='image' name='$Lang::tr{'edit'}' src='/images/edit.gif' alt='$Lang::tr{'edit'}' title='$Lang::tr{'edit'}' />
 910                                                         <input type='hidden' name='ID' value='$key' />
 911                                                 </form>
 912                                         </td>
 913
 914                                         <td align='center' $col>
 915                                                 <form method='post' name='$key' action='$ENV{'SCRIPT_NAME'}'>
 916                                                         <input type='image' name='$Lang::tr{'remove'}' src='/images/delete.gif' title='$Lang::tr{'remove'}' alt='$Lang::tr{'remove'}'>
 917                                                         <input type='hidden' name='ID' value='$key'>
 918                                                         <input type='hidden' name='WHITELIST' value='$Lang::tr{'remove'}'>
 919                                                 </form>
 920                                         </td>
 921                                 </tr>
 922 END
 923                         }
 924                 } else {
 925                         # Print notice that currently no hosts are ignored.
 926                         print "<tr>\n";
 927                         print "<td class='base' colspan='2'>$Lang::tr{'guardian no entries'}</td>\n";
 928                         print "</tr>\n";
 929                 }
 930
 931         print "</table>\n";
 932
 933         # Section to add new elements or edit existing ones.
 934 print <<END;
 935         <br>
 936         <hr>
 937         <br>
 938
 939         <div align='center'>
 940                 <table width='100%'>
 941 END
 942
 943         # Assign correct headline and button text.
 944         my $buttontext;
 945         my $entry_address;
 946         my $entry_remark;
 947
 948         # Check if an ID (key) has been given, in this case an existing entry should be edited.
 949         if ($cgiparams{'ID'} ne '') {
 950                 $buttontext = $Lang::tr{'update'};
 951                         print "<tr><td class='boldbase' colspan='3'><b>$Lang::tr{'update'}</b></td></tr>\n";
 952
 953                         # Grab address and remark for the given key.
 954                         $entry_address = $ignored{$cgiparams{'ID'}}[0];
 955                         $entry_remark = $ignored{$cgiparams{'ID'}}[1];
 956                 } else {
 957                         $buttontext = $Lang::tr{'add'};
 958                         print "<tr><td class='boldbase' colspan='3'><b>$Lang::tr{'dnsforward add a new entry'}</b></td></tr>\n";
 959                 }
 960
 961 print <<END;
 962                         <form method='post' action='$ENV{'SCRIPT_NAME'}'>
 963                         <input type='hidden' name='ID' value='$cgiparams{'ID'}'>
 964                         <tr>
 965                                 <td width='30%'>$Lang::tr{'ip address'}: </td>
 966                                 <td width='50%'><input type='text' name='IGNORE_ENTRY_ADDRESS' value='$entry_address' size='24' /></td>
 967
 968                                 <td width='30%'>$Lang::tr{'remark'}: </td>
 969                                 <td wicth='50%'><input type='text' name=IGNORE_ENTRY_REMARK value='$entry_remark' size='24' /></td>
 970                                 <td align='center' width='20%'><input type='submit' name='WHITELIST' value='$buttontext' /></td>
 971                         </tr>
 972                         </form>
 973                 </table>
 974         </div>
 975 END
 976
 977 &Header::closebox();
 978
 979 # Only show the section for configuring the ruleset if one is present.
 980 if (%idsrules) {
 981         &Header::openbox('100%', 'LEFT', $Lang::tr{'intrusion detection system rules'});
 982
 983                 print"<form method='POST' action='$ENV{'SCRIPT_NAME'}'>\n";
 984
 985                 # Output display table for rule files
 986                 print "<table width='100%'>\n";
 987
 988                 # Loop over each rule file
 989                 foreach my $rulefile (sort keys(%idsrules)) {
 990                         my $rulechecked = '';
 991
 992                         # Check if rule file is enabled
 993                         if ($idsrules{$rulefile}{'Rulefile'}{'State'} eq 'on') {
 994                                 $rulechecked = 'CHECKED';
 995                         }
 996
 997                         # Convert rulefile name into category name.
 998                         my $categoryname = &_rulefile_to_category($rulefile);
 999
1000                         # Table and rows for the rule files.
1001                         print"<tr>\n";
1002                         print"<td class='base' width='5%'>\n";
1003                         print"<input type='checkbox' name='$rulefile' $rulechecked>\n";
1004                         print"</td>\n";
1005                         print"<td class='base' width='90%'><b>$rulefile</b></td>\n";
1006                         print"<td class='base' width='5%' align='right'>\n";
1007                         print"<a href=\"javascript:showhide('$categoryname')\">SHOW</a>\n";
1008                         print"</td>\n";
1009                         print"</tr>\n";
1010
1011                         # Rows which will be hidden per default and will contain the single rules.
1012                         print"<tr  style='display:none' id='$categoryname'>\n";
1013                         print"<td colspan='3'>\n";
1014
1015                         # Local vars
1016                         my $lines;
1017                         my $rows;
1018                         my $col;
1019
1020                         # New table for the single rules.
1021                         print "<table width='100%'>\n";
1022
1023                         # Loop over rule file rules
1024                         foreach my $sid (sort {$a <=> $b} keys(%{$idsrules{$rulefile}})) {
1025                                 # Local vars
1026                                 my $ruledefchecked = '';
1027
1028                                 # Skip rulefile itself.
1029                                 next if ($sid eq "Rulefile");
1030
1031                                 # If 2 rules have been displayed, start a new row
1032                                 if (($lines % 2) == 0) {
1033                                         print "</tr><tr>\n";
1034
1035                                         # Increase rows by once.
1036                                         $rows++;
1037                                 }
1038
1039                                 # Colour lines.
1040                                 if ($rows % 2) {
1041                                         $col="bgcolor='$color{'color20'}'";
1042                                 } else {
1043                                         $col="bgcolor='$color{'color22'}'";
1044                                 }
1045
1046                                 # Set rule state
1047                                 if ($idsrules{$rulefile}{$sid}{'State'} eq 'on') {
1048                                         $ruledefchecked = 'CHECKED';
1049                                 }
1050
1051                                 # Create rule checkbox and display rule description
1052                                 print "<td class='base' width='5%' align='right' $col>\n";
1053                                 print "<input type='checkbox' NAME='$sid' $ruledefchecked>\n";
1054                                 print "</td>\n";
1055                                 print "<td class='base' width='45%' $col>$idsrules{$rulefile}{$sid}{'Description'}</td>";
1056
1057                                 # Increment rule count
1058                                 $lines++;
1059                         }
1060
1061                         # If do not have a second rule for row, create empty cell
1062                         if (($lines % 2) != 0) {
1063                                 print "<td class='base'></td>";
1064                         }
1065
1066                         # Close display table
1067                         print "</tr></table></td></tr>";
1068                 }
1069
1070                 # Close display table
1071                 print "</table>";
1072
1073 print <<END
1074 <table width='100%'>
1075 <tr>
1076         <td width='100%' align='right'><input type='submit' name='RULESET' value='$Lang::tr{'update'}'>
1077                 &nbsp; <!-- space for future online help link -->
1078         </td>
1079 </tr>
1080 </table>
1081 </form>
1082 END
1083 ;
1084         &Header::closebox();
1085 }
1086
1087 &Header::closebigbox();
1088 &Header::closepage();
1089
1090 #
1091 ## A function to display a notice, to lock the webpage and
1092 ## tell the user which action currently will be performed.
1093 #
1094 sub working_notice ($) {
1095         my ($message) = @_;
1096
1097         &Header::openpage($Lang::tr{'intrusion detection system'}, 1, '');
1098         &Header::openbigbox('100%', 'left', '', $errormessage);
1099         &Header::openbox( 'Waiting', 1,);
1100                 print <<END;
1101                         <table>
1102                                 <tr>
1103                                         <td><img src='/images/indicator.gif' alt='$Lang::tr{'aktiv'}' /></td>
1104                                         <td>$message</td>
1105                                 </tr>
1106                         </table>
1107 END
1108         &Header::closebox();
1109         &Header::closebigbox();
1110         &Header::closepage();
1111 }
1112
1113 #
1114 ## A tiny function to perform a reload of the webpage after one second.
1115 #
1116 sub reload () {
1117         print "<meta http-equiv='refresh' content='1'>\n";
1118
1119         # Stop the script.
1120         exit;
1121 }
1122
1123 #
1124 ## Private function to read-in and parse rules of a given rulefile.
1125 #
1126 ## The given file will be read, parsed and all valid rules will be stored by ID,
1127 ## message/description and it's state in the idsrules hash.
1128 #
1129 sub readrulesfile ($) {
1130         my $rulefile = shift;
1131
1132         # Open rule file and read in contents
1133         open(RULEFILE, "$IDS::rulespath/$rulefile") or die "Unable to read $rulefile!";
1134
1135         # Store file content in an array.
1136         my @lines = <RULEFILE>;
1137
1138         # Close file.
1139         close(RULEFILE);
1140
1141         # Loop over rule file contents
1142         foreach my $line (@lines) {
1143                 # Remove whitespaces.
1144                 chomp $line;
1145
1146                 # Skip blank  lines.
1147                 next if ($line =~ /^\s*$/);
1148
1149                 # Local vars.
1150                 my $sid;
1151                 my $msg;
1152
1153                 # Gather rule sid and message from the ruleline.
1154                 if ($line =~ m/.*msg:\"(.*?)\"\; .* sid:(.*?); /) {
1155                         $msg = $1;
1156                         $sid = $2;
1157
1158                         # Check if a rule has been found.
1159                         if ($sid && $msg) {
1160                                 # Add rule to the idsrules hash.
1161                                 $idsrules{$rulefile}{$sid}{'Description'} = $msg;
1162
1163                                 # Grab status of the rule. Check if ruleline starts with a "dash".
1164                                 if ($line =~ /^\#/) {
1165                                         # If yes, the rule is disabled.
1166                                         $idsrules{$rulefile}{$sid}{'State'} = "off";
1167                                 } else {
1168                                         # Otherwise the rule is enabled.
1169                                         $idsrules{$rulefile}{$sid}{'State'} = "on";
1170                                 }
1171                         }
1172                 }
1173         }
1174 }
1175
1176 #
1177 ## Function to get the used memory of a given process-id.
1178 #
1179 sub get_memory_usage($) {
1180         my ($pid) = @_;
1181
1182         my $memory = 0;
1183
1184         # Try to open the status file for the given process-id on the pseudo
1185         # file system proc.
1186         if (open(FILE, "/proc/$pid/status")) {
1187                 # Loop through the entire file.
1188                 while (<FILE>) {
1189                         # Splitt current line content and store them into variables.
1190                         my ($key, $value) = split(":", $_, 2);
1191
1192                         # Check if the current key is the one which contains the memory usage.
1193                         # The wanted one is VmRSS which contains the Real-memory (resident set)
1194                         # of the entire process.
1195                         if ($key eq "VmRSS") {
1196                                 # Found the memory usage add it to the memory variable.
1197                                 $memory += $value;
1198
1199                                 # Break the loop.
1200                                 last;
1201                         }
1202                 }
1203
1204                 # Close file handle.
1205                 close(FILE);
1206
1207                 # Return memory usage.
1208                 return $memory;
1209         }
1210
1211         # If the file could not be open, return nothing.
1212         return;
1213 }
1214
1215 #
1216 ## Function to read-in the given enabled or disables sids file.
1217 #
1218 sub read_enabled_disabled_sids_file($) {
1219         my ($file) = @_;
1220
1221         # Temporary hash to store the sids and their state. It will be
1222         # returned at the end of this function.
1223         my %temphash;
1224
1225         # Open the given filename.
1226         open(FILE, "$file") or die "Could not open $file. $!\n";
1227
1228         # Loop through the file.
1229         while(<FILE>) {
1230                 # Remove newlines.
1231                 chomp $_;
1232
1233                 # Skip blank lines.
1234                 next if ($_ =~ /^\s*$/);
1235
1236                 # Skip coments.
1237                 next if ($_ =~ /^\#/);
1238
1239                 # Splitt line into sid and state part.
1240                 my ($state, $sid) = split(" ", $_);
1241
1242                 # Skip line if the sid is not numeric.
1243                 next unless ($sid =~ /\d+/ );
1244
1245                 # Check if the sid was enabled.
1246                 if ($state eq "enablesid") {
1247                         # Add the sid and its state as enabled to the temporary hash.
1248                         $temphash{$sid} = "enabled";
1249                 # Check if the sid was disabled.
1250                 } elsif ($state eq "disablesid") {
1251                         # Add the sid and its state as disabled to the temporary hash.
1252                         $temphash{$sid} = "disabled";
1253                 # Invalid state - skip the current sid and state.
1254                 } else {
1255                         next;
1256                 }
1257         }
1258
1259         # Close filehandle.
1260         close(FILE);
1261
1262         # Return the hash.
1263         return %temphash;
1264 }
1265
1266 #
1267 ## Private function to convert a given rulefile to a category name.
1268 ## ( No file extension anymore and if the name contained a dot, it
1269 ## would be replaced by a underline sign.)
1270 #
1271 sub _rulefile_to_category($) {
1272         my ($filename) = @_;
1273
1274         # Splitt the filename into single chunks and store them in a
1275         # temorary array.
1276         my @parts = split(/\./, $filename);
1277
1278         # Return / Remove last element of the temporary array.
1279         # This removes the file extension.
1280         pop @parts;
1281
1282         # Join together the single elements of the temporary array.
1283         # If these are more than one, use a "underline" for joining.
1284         my $category = join '_', @parts;
1285
1286         # Return the converted filename.
1287         return $category;
1288 }