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", $cgiparams{'AUTOUPDATE_INTERVAL'});
 324         }
 325
 326         # Check if a ruleset is present - if not or the source has been changed download it.
 327         if((! %idsrules) || ($oldsettings{'RULES'} ne $cgiparams{'RULES'})) {
 328                 # Check if the red device is active.
 329                 unless (-e "${General::swroot}/red/active") {
 330                         $errormessage = "$Lang::tr{'could not download latest updates'} - $Lang::tr{'system is offline'}";
 331                 }
 332
 333                 # Check if enought free disk space is availabe.
 334                 if(&IDS::checkdiskspace()) {
 335                         $errormessage = "$Lang::tr{'not enough disk space'}";
 336                 }
 337
 338                 # Check if any errors happend.
 339                 unless ($errormessage) {
 340                         # Lock the webpage and print notice about downloading
 341                         # a new ruleset.
 342                         &working_notice("$Lang::tr{'snort working'}");
 343
 344                         # Call subfunction to download the ruleset.
 345                         if(&IDS::downloadruleset()) {
 346                                 $errormessage = $Lang::tr{'could not download latest updates'};
 347
 348                                 # Call function to store the errormessage.
 349                                 &IDS::_store_error_message($errormessage);
 350                         } else {
 351                                 # Call subfunction to launch oinkmaster.
 352                                 &IDS::oinkmaster();
 353                         }
 354
 355                         # Check if the IDS is running.
 356                         if(&IDS::ids_is_running()) {
 357                                 # Call suricatactrl to stop the IDS - because of the changed
 358                                 # ruleset - the use has to configure it before suricata can be
 359                                 # used again.
 360                                 &IDS::call_suricatactrl("stop");
 361                         }
 362
 363                         # Perform a reload of the page.
 364                         &reload();
 365                 }
 366         }
 367
 368 # Save ruleset.
 369 } elsif ($cgiparams{'RULESET'} eq $Lang::tr{'update'}) {
 370         # Arrays to store which rulefiles have been enabled and will be used.
 371         my @enabled_rulefiles;
 372
 373         # Hash to store the user-enabled and disabled sids.
 374         my %enabled_disabled_sids;
 375
 376         # Loop through the hash of idsrules.
 377         foreach my $rulefile(keys %idsrules) {
 378                 # Check if the rulefile is enabled.
 379                 if ($cgiparams{$rulefile} eq "on") {
 380                         # Add rulefile to the array of enabled rulefiles.
 381                         push(@enabled_rulefiles, $rulefile);
 382
 383                         # Drop item from cgiparams hash.
 384                         delete $cgiparams{$rulefile};
 385                 }
 386         }
 387
 388         # Read-in the files for enabled/disabled sids.
 389         # This will be done by calling the read_enabled_disabled_sids_file function two times
 390         # and merge the returned hashes together into the enabled_disabled_sids hash.
 391         %enabled_disabled_sids = (
 392                 &read_enabled_disabled_sids_file($IDS::disabled_sids_file),
 393                 &read_enabled_disabled_sids_file($IDS::enabled_sids_file));
 394
 395         # Loop through the hash of idsrules.
 396         foreach my $rulefile (keys %idsrules) {
 397                 # Loop through the single rules of the rulefile.
 398                 foreach my $sid (keys %{$idsrules{$rulefile}}) {
 399                         # Skip the current sid if it is not numeric.
 400                         next unless ($sid =~ /\d+/ );
 401
 402                         # Check if there exists a key in the cgiparams hash for this sid.
 403                         if (exists($cgiparams{$sid})) {
 404                                 # Look if the rule is disabled.
 405                                 if ($idsrules{$rulefile}{$sid}{'State'} eq "off") {
 406                                         # Check if the state has been set to 'on'.
 407                                         if ($cgiparams{$sid} eq "on") {
 408                                                 # Add/Modify the sid to/in the enabled_disabled_sids hash.
 409                                                 $enabled_disabled_sids{$sid} = "enabled";
 410
 411                                                 # Drop item from cgiparams hash.
 412                                                 delete $cgiparams{$rulefile}{$sid};
 413                                         }
 414                                 }
 415                         } else {
 416                                 # Look if the rule is enabled.
 417                                 if ($idsrules{$rulefile}{$sid}{'State'} eq "on") {
 418                                         # Check if the state is 'on' and should be disabled.
 419                                         # In this case there is no entry
 420                                         # for the sid in the cgiparams hash.
 421                                         # Add/Modify it to/in the enabled_disabled_sids hash.
 422                                         $enabled_disabled_sids{$sid} = "disabled";
 423
 424                                         # Drop item from cgiparams hash.
 425                                         delete $cgiparams{$rulefile}{$sid};
 426                                 }
 427                         }
 428                 }
 429         }
 430
 431         # Open enabled sid's file for writing.
 432         open(ENABLED_FILE, ">$IDS::enabled_sids_file") or die "Could not write to $IDS::enabled_sids_file. $!\n";
 433
 434         # Open disabled sid's file for writing.
 435         open(DISABLED_FILE, ">$IDS::disabled_sids_file") or die "Could not write to $IDS::disabled_sids_file. $!\n";
 436
 437         # Write header to the files.
 438         print ENABLED_FILE "#Autogenerated file. Any custom changes will be overwritten!\n";
 439         print DISABLED_FILE "#Autogenerated file. Any custom changes will be overwritten!\n";
 440
 441         # Check if the hash for enabled/disabled files contains any entries.
 442         if (%enabled_disabled_sids) {
 443                 # Loop through the hash.
 444                 foreach my $sid (keys %enabled_disabled_sids) {
 445                         # Check if the sid is enabled.
 446                         if ($enabled_disabled_sids{$sid} eq "enabled") {
 447                                 # Print the sid to the enabled_sids file.
 448                                 print ENABLED_FILE "enablesid $sid\n";
 449                         # Check if the sid is disabled.
 450                         } elsif ($enabled_disabled_sids{$sid} eq "disabled") {
 451                                 # Print the sid to the disabled_sids file.
 452                                 print DISABLED_FILE "disablesid $sid\n";
 453                         # Something strange happende - skip the current sid.
 454                         } else {
 455                                 next;
 456                         }
 457                 }
 458         }
 459
 460         # Close file for enabled_sids after writing.
 461         close(ENABLED_FILE);
 462
 463         # Close file for disabled_sids after writing.
 464         close(DISABLED_FILE);
 465
 466         # Call function to generate and write the used rulefiles file.
 467         &IDS::write_used_rulefiles_file(@enabled_rulefiles);
 468
 469         # Lock the webpage and print message.
 470         &working_notice("$Lang::tr{'snort working'}");
 471
 472         # Call oinkmaster to alter the ruleset.
 473         &IDS::oinkmaster();
 474
 475         # Check if the IDS is running.
 476         if(&IDS::ids_is_running()) {
 477                 # Call suricatactrl to perform a reload.
 478                 &IDS::call_suricatactrl("reload");
 479         }
 480
 481         # Reload page.
 482         &reload();
 483
 484 # Download new ruleset.
 485 } elsif ($cgiparams{'RULESET'} eq $Lang::tr{'update ruleset'}) {
 486         # Check if the red device is active.
 487         unless (-e "${General::swroot}/red/active") {
 488                 $errormessage = "$Lang::tr{'could not download latest updates'} - $Lang::tr{'system is offline'}";
 489         }
 490
 491         # Check if enought free disk space is availabe.
 492         if(&IDS::checkdiskspace()) {
 493                 $errormessage = "$Lang::tr{'not enough disk space'}";
 494         }
 495
 496         # Check if any errors happend.
 497         unless ($errormessage) {
 498                 # Lock the webpage and print notice about downloading
 499                 # a new ruleset.
 500                 &working_notice("$Lang::tr{'snort working'}");
 501
 502                 # Call subfunction to download the ruleset.
 503                 if(&IDS::downloadruleset()) {
 504                         $errormessage = $Lang::tr{'could not download latest updates'};
 505
 506                         # Call function to store the errormessage.
 507                         &IDS::_store_error_message($errormessage);
 508
 509                         # Preform a reload of the page.
 510                         &reload();
 511                 } else {
 512                         # Call subfunction to launch oinkmaster.
 513                         &IDS::oinkmaster();
 514
 515                         # Check if the IDS is running.
 516                         if(&IDS::ids_is_running()) {
 517                                 # Call suricatactrl to perform a reload.
 518                                 &IDS::call_suricatactrl("reload");
 519                         }
 520
 521                         # Perform a reload of the page.
 522                         &reload();
 523                 }
 524         }
 525 # Save snort settings.
 526 } elsif ($cgiparams{'IDS'} eq $Lang::tr{'save'}) {
 527         my %oldidssettings;
 528         my $reload_page;
 529         my $monitored_zones = 0;
 530
 531         # Read-in current (old) IDS settings.
 532         &General::readhash("$IDS::ids_settings_file", \%oldidssettings);
 533
 534         # Prevent form name from been stored in conf file.
 535         delete $cgiparams{'IDS'};
 536
 537         # Check if the IDS should be enabled.
 538         if ($cgiparams{'ENABLE_IDS'} eq "on") {
 539                 # Check if any ruleset is available. Otherwise abort and display an error.
 540                 unless(%idsrules) {
 541                         $errormessage = $Lang::tr{'ids no ruleset available'};
 542                 }
 543
 544                 # Loop through the array of available interfaces.
 545                 foreach my $zone (@network_zones) {
 546                         # Convert interface name into upper case.
 547                         my $zone_upper = uc($zone);
 548
 549                         # Check if the IDS is enabled for this interaces.
 550                         if ($cgiparams{"ENABLE_IDS_$zone_upper"}) {
 551                                 # Increase count.
 552                                 $monitored_zones++;
 553                         }
 554                 }
 555
 556                 # Check if at least one zone should be monitored, or show an error.
 557                 unless ($monitored_zones >= 1) {
 558                         $errormessage = $Lang::tr{'ids no network zone'};
 559                 }
 560         }
 561
 562         # Go on if there are no error messages.
 563         if (!$errormessage) {
 564                 # Store settings into settings file.
 565                 &General::writehash("$IDS::ids_settings_file", \%cgiparams);
 566         }
 567
 568         # Generate file to store the home net.
 569         &IDS::generate_home_net_file();
 570
 571         # Temporary variable to set the ruleaction.
 572         # Default is "drop" to use suricata as IPS.
 573         my $ruleaction="drop";
 574
 575         # Check if the traffic only should be monitored.
 576         if($cgiparams{'MONITOR_TRAFFIC_ONLY'} eq 'on') {
 577                 # Switch the ruleaction to "alert".
 578                 # Suricata acts as an IDS only.
 579                 $ruleaction="alert";
 580         }
 581
 582         # Write the modify sid's file and pass the taken ruleaction.
 583         &IDS::write_modify_sids_file($ruleaction);
 584
 585         # Check if "MONITOR_TRAFFIC_ONLY" has been changed.
 586         if($cgiparams{'MONITOR_TRAFFIC_ONLY'} ne $oldidssettings{'MONITOR_TRAFFIC_ONLY'}) {
 587                 # Check if a ruleset exists.
 588                 if (%idsrules) {
 589                         # Lock the webpage and print message.
 590                         &working_notice("$Lang::tr{'snort working'}");
 591
 592                         # Call oinkmaster to alter the ruleset.
 593                         &IDS::oinkmaster();
 594
 595                         # Set reload_page to "True".
 596                         $reload_page="True";
 597                 }
 598         }
 599
 600         # Check if the IDS currently is running.
 601         if(&IDS::ids_is_running()) {
 602                 # Check if ENABLE_IDS is set to on.
 603                 if($cgiparams{'ENABLE_IDS'} eq "on") {
 604                         # Call suricatactrl to perform a reload of suricata.
 605                         &IDS::call_suricatactrl("reload");
 606                 } else {
 607                         # Call suricatactrl to stop suricata.
 608                         &IDS::call_suricatactrl("stop");
 609                 }
 610         } else {
 611                 # Call suricatactrl to start suricata.
 612                 &IDS::call_suricatactrl("start");
 613         }
 614
 615         # Check if the page should be reloaded.
 616         if ($reload_page) {
 617                 # Perform a reload of the page.
 618                 &reload();
 619         }
 620 }
 621
 622 # Read-in idssettings and rulesetsettings
 623 &General::readhash("$IDS::ids_settings_file", \%idssettings);
 624 &General::readhash("$IDS::rules_settings_file", \%rulessettings);
 625
 626 # If no autoupdate intervall has been configured yet, set default value.
 627 unless(exists($rulessettings{'AUTOUPDATE_INTERVAL'})) {
 628         # Set default to "weekly".
 629         $rulessettings{'AUTOUPDATE_INTERVAL'} = 'weekly';
 630 }
 631
 632 # Read-in ignored hosts.
 633 &General::readhasharray("$IDS::settingsdir/ignored", \%ignored);
 634
 635 $checked{'ENABLE_IDS'}{'off'} = '';
 636 $checked{'ENABLE_IDS'}{'on'} = '';
 637 $checked{'ENABLE_IDS'}{$idssettings{'ENABLE_IDS'}} = "checked='checked'";
 638 $checked{'MONITOR_TRAFFIC_ONLY'}{'off'} = '';
 639 $checked{'MONITOR_TRAFFIC_ONLY'}{'on'} = '';
 640 $checked{'MONITOR_TRAFFIC_ONLY'}{$idssettings{'MONITOR_TRAFFIC_ONLY'}} = "checked='checked'";
 641 $selected{'RULES'}{'nothing'} = '';
 642 $selected{'RULES'}{'community'} = '';
 643 $selected{'RULES'}{'emerging'} = '';
 644 $selected{'RULES'}{'registered'} = '';
 645 $selected{'RULES'}{'subscripted'} = '';
 646 $selected{'RULES'}{$rulessettings{'RULES'}} = "selected='selected'";
 647 $selected{'AUTOUPDATE_INTERVAL'}{'off'} = '';
 648 $selected{'AUTOUPDATE_INTERVAL'}{'daily'} = '';
 649 $selected{'AUTOUPDATE_INTERVAL'}{'weekly'} = '';
 650 $selected{'AUTOUPDATE_INTERVAL'}{$rulessettings{'AUTOUPDATE_INTERVAL'}} = "selected='selected'";
 651
 652 &Header::openpage($Lang::tr{'intrusion detection system'}, 1, '');
 653
 654 ### Java Script ###
 655 print"<script>\n";
 656
 657 # Java script variable declaration for show and hide.
 658 print"var show = \"$Lang::tr{'ids show'}\"\;\n";
 659 print"var hide = \"$Lang::tr{'ids hide'}\"\;\n";
 660
 661 print <<END
 662         // JQuery function to show/hide the text input field for
 663         // Oinkcode/Subscription code.
 664         \$(function() {
 665                 \$('#RULES').change(function(){
 666                         if(\$('#RULES').val() == 'registered') {
 667                                 \$('#code').show();
 668                         } else if(\$('#RULES').val() == 'subscripted') {
 669                                 \$('#code').show();
 670                         } else if(\$('#RULES').val() == 'emerging_pro') {
 671                                 \$('#code').show();
 672                         } else {
 673                                 \$('#code').hide();
 674                         }
 675                 });
 676         });
 677
 678         // Tiny java script function to show/hide the rules
 679         // of a given category.
 680         function showhide(tblname) {
 681                 \$("#" + tblname).toggle();
 682
 683                 // Get current content of the span element.
 684                 var content = document.getElementById("span_" + tblname);
 685
 686                 if (content.innerHTML === show) {
 687                         content.innerHTML = hide;
 688                 } else {
 689                         content.innerHTML = show;
 690                 }
 691         }
 692 </script>
 693 END
 694 ;
 695
 696 &Header::openbigbox('100%', 'left', '', $errormessage);
 697
 698 if ($errormessage) {
 699         &Header::openbox('100%', 'left', $Lang::tr{'error messages'});
 700         print "<class name='base'>$errormessage\n";
 701         print "&nbsp;</class>\n";
 702         &Header::closebox();
 703 }
 704
 705 # Draw current state of the IDS
 706 &Header::openbox('100%', 'left', $Lang::tr{'intrusion detection system'});
 707
 708 # Check if the IDS is running and obtain the process-id.
 709 my $pid = &IDS::ids_is_running();
 710
 711 # Display some useful information, if suricata daemon is running.
 712 if ($pid) {
 713         # Gather used memory.
 714         my $memory = &get_memory_usage($pid);
 715
 716         print <<END;
 717                 <table width='95%' cellspacing='0' class='tbl'>
 718                         <tr>
 719                                 <th bgcolor='$color{'color20'}' colspan='3' align='left'><strong>$Lang::tr{'intrusion detection'}</strong></th>
 720                         </tr>
 721
 722                         <tr>
 723                                 <td class='base'>$Lang::tr{'guardian daemon'}</td>
 724                                 <td align='center' colspan='2' width='75%' bgcolor='${Header::colourgreen}'><font color='white'><strong>$Lang::tr{'running'}</strong></font></td>
 725                         </tr>
 726
 727                         <tr>
 728                                 <td class='base'></td>
 729                                 <td bgcolor='$color{'color20'}' align='center'><strong>PID</strong></td>
 730                                 <td bgcolor='$color{'color20'}' align='center'><strong>$Lang::tr{'memory'}</strong></td>
 731                         </tr>
 732
 733                         <tr>
 734                                 <td class='base'></td>
 735                                 <td bgcolor='$color{'color22'}' align='center'>$pid</td>
 736                                 <td bgcolor='$color{'color22'}' align='center'>$memory KB</td>
 737                         </tr>
 738                 </table>
 739 END
 740 } else {
 741         # Otherwise display a hint that the service is not launched.
 742         print <<END;
 743                 <table width='95%' cellspacing='0' class='tbl'>
 744                         <tr>
 745                                 <th bgcolor='$color{'color20'}' colspan='3' align='left'><strong>$Lang::tr{'intrusion detection'}</strong></th>
 746                         </tr>
 747
 748                         <tr>
 749                                 <td class='base'>$Lang::tr{'guardian daemon'}</td>
 750                                 <td align='center' width='75%' bgcolor='${Header::colourred}'><font color='white'><strong>$Lang::tr{'stopped'}</strong></font></td>
 751                         </tr>
 752                 </table>
 753 END
 754 }
 755
 756 my $rulesdate;
 757
 758 # Check if a ruleset allready has been downloaded.
 759 if ( -f "$IDS::rulestarball"){
 760         # Call stat on the filename to obtain detailed information.
 761         my @Info = stat("$IDS::rulestarball");
 762
 763         # Grab details about the creation time.
 764         $rulesdate = localtime($Info[9]);
 765 }
 766
 767 # Only show this area, if a ruleset is present.
 768 if (%idsrules) {
 769
 770         print <<END
 771
 772         <br><br><h2>$Lang::tr{'settings'}</h2>
 773
 774         <form method='post' action='$ENV{'SCRIPT_NAME'}'>
 775                 <table width='100%' border='0'>
 776                         <tr>
 777                                 <td class='base' colspan='2'>
 778                                         <input type='checkbox' name='ENABLE_IDS' $checked{'ENABLE_IDS'}{'on'}>&nbsp;$Lang::tr{'ids enable'}
 779                                 </td>
 780
 781                                 <td class='base' colspan='2'>
 782                                         <input type='checkbox' name='MONITOR_TRAFFIC_ONLY' $checked{'MONITOR_TRAFFIC_ONLY'}{'on'}>&nbsp;$Lang::tr{'ids monitor traffic only'}
 783                         </td>
 784                         </tr>
 785
 786                         <tr>
 787                                 <td><br><br></td>
 788                                 <td><br><br></td>
 789                                 <td><br><br></td>
 790                                 <td><br><br></td>
 791                         </tr>
 792
 793                         <tr>
 794                                 <td colspan='4'><b>$Lang::tr{'ids monitored interfaces'}</b><br></td>
 795                         </tr>
 796
 797                         <tr>
 798 END
 799 ;
 800
 801         # Loop through the array of available networks and print config options.
 802         foreach my $zone (@network_zones) {
 803                 my $checked_input;
 804                 my $checked_forward;
 805
 806                 # Convert current zone name to upper case.
 807                 my $zone_upper = uc($zone);
 808
 809                 # Set zone name.
 810                 my $zone_name = $zone;
 811
 812                 # Dirty hack to get the correct language string for the red zone.
 813                 if ($zone eq "red") {
 814                         $zone_name = "red1";
 815                 }
 816
 817                 # Grab checkbox status from settings hash.
 818                 if ($idssettings{"ENABLE_IDS_$zone_upper"} eq "on") {
 819                         $checked_input = "checked = 'checked'";
 820                 }
 821
 822                 print "<td class='base' width='25%'>\n";
 823                 print "<input type='checkbox' name='ENABLE_IDS_$zone_upper' $checked_input>\n";
 824                 print "&nbsp;$Lang::tr{'enabled on'}<font color='$colourhash{$zone}'> $Lang::tr{$zone_name}</font>\n";
 825                 print "</td>\n";
 826         }
 827
 828 print <<END
 829                         </tr>
 830                 </table>
 831
 832                 <br><br>
 833
 834                 <table width='100%'>
 835                         <tr>
 836                                 <td align='right'><input type='submit' name='IDS' value='$Lang::tr{'save'}' /></td>
 837                         </tr>
 838                 </table>
 839         </form>
 840 END
 841 ;
 842
 843 }
 844
 845 &Header::closebox();
 846
 847 # Draw elements for ruleset configuration.
 848 &Header::openbox('100%', 'center', $Lang::tr{'ids ruleset settings'});
 849
 850 print <<END
 851 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
 852         <table width='100%' border='0'>
 853                 <tr>
 854                         <td><b>$Lang::tr{'ids rules update'}</b></td>
 855                         <td><b>$Lang::tr{'ids automatic rules update'}</b></td>
 856                 </tr>
 857
 858                 <tr>
 859                         <td><select name='RULES' id='RULES'>
 860                                 <option value='emerging' $selected{'RULES'}{'emerging'} >$Lang::tr{'emerging rules'}</option>
 861                                 <option value='emerging_pro' $selected{'RULES'}{'emerging_pro'} >$Lang::tr{'emerging pro rules'}</option>
 862                                 <option value='community' $selected{'RULES'}{'community'} >$Lang::tr{'community rules'}</option>
 863                                 <option value='registered' $selected{'RULES'}{'registered'} >$Lang::tr{'registered user rules'}</option>
 864                                 <option value='subscripted' $selected{'RULES'}{'subscripted'} >$Lang::tr{'subscripted user rules'}</option>
 865                         </select>
 866                         </td>
 867
 868                         <td>
 869                                 <select name='AUTOUPDATE_INTERVAL'>
 870                                         <option value='off' $selected{'AUTOUPDATE_INTERVAL'}{'off'} >- $Lang::tr{'Disabled'} -</option>
 871                                         <option value='daily' $selected{'AUTOUPDATE_INTERVAL'}{'daily'} >$Lang::tr{'Daily'}</option>
 872                                         <option value='weekly' $selected{'AUTOUPDATE_INTERVAL'}{'weekly'} >$Lang::tr{'Weekly'}</option>
 873                                 </select>
 874                         </td>
 875                 </tr>
 876
 877                 <tr>
 878                         <td colspan='2'><br><br></td>
 879                 </tr>
 880
 881                 <tr style='display:none' id='code'>
 882                         <td colspan='2'>Oinkcode:&nbsp;<input type='text' size='40' name='OINKCODE' value='$rulessettings{'OINKCODE'}'></td>
 883                 </tr>
 884
 885                 <tr>
 886                         <td>&nbsp;</td>
 887
 888                         <td align='right'>
 889 END
 890 ;
 891                         # Check if a ruleset has been downloaded yet.
 892                         if (%idsrules) {
 893                                 # Display button to update the ruleset.
 894                                 print"<input type='submit' name='RULESET' value='$Lang::tr{'update ruleset'}'>\n";
 895                 }
 896 print <<END;
 897                                 <input type='submit' name='RULESET' value='$Lang::tr{'save'}'>
 898                         </td>
 899
 900                 </tr>
 901         </table>
 902 </form>
 903 END
 904 ;
 905
 906 &Header::closebox();
 907
 908 #
 909 # Whitelist / Ignorelist
 910 #
 911 &Header::openbox('100%', 'center', $Lang::tr{'guardian ignored hosts'});
 912
 913 print <<END;
 914         <table width='100%'>
 915                 <tr>
 916                         <td class='base' bgcolor='$color{'color20'}'><b>$Lang::tr{'ip address'}</b></td>
 917                         <td class='base' bgcolor='$color{'color20'}'><b>$Lang::tr{'remark'}</b></td>
 918                         <td class='base' colspan='3' bgcolor='$color{'color20'}'></td>
 919                 </tr>
 920 END
 921                 # Check if some hosts have been added to be ignored.
 922                 if (keys (%ignored)) {
 923                         my $col = "";
 924
 925                         # Loop through all entries of the hash.
 926                         while( (my $key) = each %ignored)  {
 927                                 # Assign data array positions to some nice variable names.
 928                                 my $address = $ignored{$key}[0];
 929                                 my $remark = $ignored{$key}[1];
 930                                 my $status  = $ignored{$key}[2];
 931
 932                                 # Check if the key (id) number is even or not.
 933                                 if ($cgiparams{'ID'} eq $key) {
 934                                         $col="bgcolor='${Header::colouryellow}'";
 935                                 } elsif ($key % 2) {
 936                                         $col="bgcolor='$color{'color22'}'";
 937                                 } else {
 938                                         $col="bgcolor='$color{'color20'}'";
 939                                 }
 940
 941                                 # Choose icon for the checkbox.
 942                                 my $gif;
 943                                 my $gdesc;
 944
 945                                 # Check if the status is enabled and select the correct image and description.
 946                                 if ($status eq 'enabled' ) {
 947                                         $gif = 'on.gif';
 948                                         $gdesc = $Lang::tr{'click to disable'};
 949                                 } else {
 950                                         $gif = 'off.gif';
 951                                         $gdesc = $Lang::tr{'click to enable'};
 952                                 }
 953
 954 print <<END;
 955                                 <tr>
 956                                         <td width='20%' class='base' $col>$address</td>
 957                                         <td width='65%' class='base' $col>$remark</td>
 958
 959                                         <td align='center' $col>
 960                                                 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
 961                                                         <input type='hidden' name='WHITELIST' value='$Lang::tr{'toggle enable disable'}' />
 962                                                         <input type='image' name='$Lang::tr{'toggle enable disable'}' src='/images/$gif' alt='$gdesc' title='$gdesc' />
 963                                                         <input type='hidden' name='ID' value='$key' />
 964                                                 </form>
 965                                         </td>
 966
 967                                         <td align='center' $col>
 968                                                 <form method='post' action='$ENV{'SCRIPT_NAME'}'>
 969                                                         <input type='hidden' name='WHITELIST' value='$Lang::tr{'edit'}' />
 970                                                         <input type='image' name='$Lang::tr{'edit'}' src='/images/edit.gif' alt='$Lang::tr{'edit'}' title='$Lang::tr{'edit'}' />
 971                                                         <input type='hidden' name='ID' value='$key' />
 972                                                 </form>
 973                                         </td>
 974
 975                                         <td align='center' $col>
 976                                                 <form method='post' name='$key' action='$ENV{'SCRIPT_NAME'}'>
 977                                                         <input type='image' name='$Lang::tr{'remove'}' src='/images/delete.gif' title='$Lang::tr{'remove'}' alt='$Lang::tr{'remove'}'>
 978                                                         <input type='hidden' name='ID' value='$key'>
 979                                                         <input type='hidden' name='WHITELIST' value='$Lang::tr{'remove'}'>
 980                                                 </form>
 981                                         </td>
 982                                 </tr>
 983 END
 984                         }
 985                 } else {
 986                         # Print notice that currently no hosts are ignored.
 987                         print "<tr>\n";
 988                         print "<td class='base' colspan='2'>$Lang::tr{'guardian no entries'}</td>\n";
 989                         print "</tr>\n";
 990                 }
 991
 992         print "</table>\n";
 993
 994         # Section to add new elements or edit existing ones.
 995 print <<END;
 996         <br>
 997         <hr>
 998         <br>
 999
1000         <div align='center'>
1001                 <table width='100%'>
1002 END
1003
1004         # Assign correct headline and button text.
1005         my $buttontext;
1006         my $entry_address;
1007         my $entry_remark;
1008
1009         # Check if an ID (key) has been given, in this case an existing entry should be edited.
1010         if ($cgiparams{'ID'} ne '') {
1011                 $buttontext = $Lang::tr{'update'};
1012                         print "<tr><td class='boldbase' colspan='3'><b>$Lang::tr{'update'}</b></td></tr>\n";
1013
1014                         # Grab address and remark for the given key.
1015                         $entry_address = $ignored{$cgiparams{'ID'}}[0];
1016                         $entry_remark = $ignored{$cgiparams{'ID'}}[1];
1017                 } else {
1018                         $buttontext = $Lang::tr{'add'};
1019                         print "<tr><td class='boldbase' colspan='3'><b>$Lang::tr{'dnsforward add a new entry'}</b></td></tr>\n";
1020                 }
1021
1022 print <<END;
1023                         <form method='post' action='$ENV{'SCRIPT_NAME'}'>
1024                         <input type='hidden' name='ID' value='$cgiparams{'ID'}'>
1025                         <tr>
1026                                 <td width='30%'>$Lang::tr{'ip address'}: </td>
1027                                 <td width='50%'><input type='text' name='IGNORE_ENTRY_ADDRESS' value='$entry_address' size='24' /></td>
1028
1029                                 <td width='30%'>$Lang::tr{'remark'}: </td>
1030                                 <td wicth='50%'><input type='text' name=IGNORE_ENTRY_REMARK value='$entry_remark' size='24' /></td>
1031                                 <td align='center' width='20%'><input type='submit' name='WHITELIST' value='$buttontext' /></td>
1032                         </tr>
1033                         </form>
1034                 </table>
1035         </div>
1036 END
1037
1038 &Header::closebox();
1039
1040 # Only show the section for configuring the ruleset if one is present.
1041 if (%idsrules) {
1042         &Header::openbox('100%', 'LEFT', $Lang::tr{'intrusion detection system rules'});
1043
1044                 print"<form method='POST' action='$ENV{'SCRIPT_NAME'}'>\n";
1045
1046                 # Output display table for rule files
1047                 print "<table width='100%'>\n";
1048
1049                 # Loop over each rule file
1050                 foreach my $rulefile (sort keys(%idsrules)) {
1051                         my $rulechecked = '';
1052
1053                         # Check if rule file is enabled
1054                         if ($idsrules{$rulefile}{'Rulefile'}{'State'} eq 'on') {
1055                                 $rulechecked = 'CHECKED';
1056                         }
1057
1058                         # Convert rulefile name into category name.
1059                         my $categoryname = &_rulefile_to_category($rulefile);
1060
1061                         # Table and rows for the rule files.
1062                         print"<tr>\n";
1063                         print"<td class='base' width='5%'>\n";
1064                         print"<input type='checkbox' name='$rulefile' $rulechecked>\n";
1065                         print"</td>\n";
1066                         print"<td class='base' width='90%'><b>$rulefile</b></td>\n";
1067                         print"<td class='base' width='5%' align='right'>\n";
1068                         print"<a href=\"javascript:showhide('$categoryname')\"><span id='span_$categoryname'>$Lang::tr{'ids show'}</span></a>\n";
1069                         print"</td>\n";
1070                         print"</tr>\n";
1071
1072                         # Rows which will be hidden per default and will contain the single rules.
1073                         print"<tr  style='display:none' id='$categoryname'>\n";
1074                         print"<td colspan='3'>\n";
1075
1076                         # Local vars
1077                         my $lines;
1078                         my $rows;
1079                         my $col;
1080
1081                         # New table for the single rules.
1082                         print "<table width='100%'>\n";
1083
1084                         # Loop over rule file rules
1085                         foreach my $sid (sort {$a <=> $b} keys(%{$idsrules{$rulefile}})) {
1086                                 # Local vars
1087                                 my $ruledefchecked = '';
1088
1089                                 # Skip rulefile itself.
1090                                 next if ($sid eq "Rulefile");
1091
1092                                 # If 2 rules have been displayed, start a new row
1093                                 if (($lines % 2) == 0) {
1094                                         print "</tr><tr>\n";
1095
1096                                         # Increase rows by once.
1097                                         $rows++;
1098                                 }
1099
1100                                 # Colour lines.
1101                                 if ($rows % 2) {
1102                                         $col="bgcolor='$color{'color20'}'";
1103                                 } else {
1104                                         $col="bgcolor='$color{'color22'}'";
1105                                 }
1106
1107                                 # Set rule state
1108                                 if ($idsrules{$rulefile}{$sid}{'State'} eq 'on') {
1109                                         $ruledefchecked = 'CHECKED';
1110                                 }
1111
1112                                 # Create rule checkbox and display rule description
1113                                 print "<td class='base' width='5%' align='right' $col>\n";
1114                                 print "<input type='checkbox' NAME='$sid' $ruledefchecked>\n";
1115                                 print "</td>\n";
1116                                 print "<td class='base' width='45%' $col>$idsrules{$rulefile}{$sid}{'Description'}</td>";
1117
1118                                 # Increment rule count
1119                                 $lines++;
1120                         }
1121
1122                         # If do not have a second rule for row, create empty cell
1123                         if (($lines % 2) != 0) {
1124                                 print "<td class='base'></td>";
1125                         }
1126
1127                         # Close display table
1128                         print "</tr></table></td></tr>";
1129                 }
1130
1131                 # Close display table
1132                 print "</table>";
1133
1134 print <<END
1135 <table width='100%'>
1136 <tr>
1137         <td width='100%' align='right'><input type='submit' name='RULESET' value='$Lang::tr{'update'}'>
1138                 &nbsp; <!-- space for future online help link -->
1139         </td>
1140 </tr>
1141 </table>
1142 </form>
1143 END
1144 ;
1145         &Header::closebox();
1146 }
1147
1148 &Header::closebigbox();
1149 &Header::closepage();
1150
1151 #
1152 ## A function to display a notice, to lock the webpage and
1153 ## tell the user which action currently will be performed.
1154 #
1155 sub working_notice ($) {
1156         my ($message) = @_;
1157
1158         &Header::openpage($Lang::tr{'intrusion detection system'}, 1, '');
1159         &Header::openbigbox('100%', 'left', '', $errormessage);
1160         &Header::openbox( 'Waiting', 1,);
1161                 print <<END;
1162                         <table>
1163                                 <tr>
1164                                         <td><img src='/images/indicator.gif' alt='$Lang::tr{'aktiv'}' /></td>
1165                                         <td>$message</td>
1166                                 </tr>
1167                         </table>
1168 END
1169         &Header::closebox();
1170         &Header::closebigbox();
1171         &Header::closepage();
1172 }
1173
1174 #
1175 ## A tiny function to perform a reload of the webpage after one second.
1176 #
1177 sub reload () {
1178         print "<meta http-equiv='refresh' content='1'>\n";
1179
1180         # Stop the script.
1181         exit;
1182 }
1183
1184 #
1185 ## Private function to read-in and parse rules of a given rulefile.
1186 #
1187 ## The given file will be read, parsed and all valid rules will be stored by ID,
1188 ## message/description and it's state in the idsrules hash.
1189 #
1190 sub readrulesfile ($) {
1191         my $rulefile = shift;
1192
1193         # Open rule file and read in contents
1194         open(RULEFILE, "$IDS::rulespath/$rulefile") or die "Unable to read $rulefile!";
1195
1196         # Store file content in an array.
1197         my @lines = <RULEFILE>;
1198
1199         # Close file.
1200         close(RULEFILE);
1201
1202         # Loop over rule file contents
1203         foreach my $line (@lines) {
1204                 # Remove whitespaces.
1205                 chomp $line;
1206
1207                 # Skip blank  lines.
1208                 next if ($line =~ /^\s*$/);
1209
1210                 # Local vars.
1211                 my $sid;
1212                 my $msg;
1213
1214                 # Gather rule sid and message from the ruleline.
1215                 if ($line =~ m/.*msg:\"(.*?)\"\; .* sid:(.*?); /) {
1216                         $msg = $1;
1217                         $sid = $2;
1218
1219                         # Check if a rule has been found.
1220                         if ($sid && $msg) {
1221                                 # Add rule to the idsrules hash.
1222                                 $idsrules{$rulefile}{$sid}{'Description'} = $msg;
1223
1224                                 # Grab status of the rule. Check if ruleline starts with a "dash".
1225                                 if ($line =~ /^\#/) {
1226                                         # If yes, the rule is disabled.
1227                                         $idsrules{$rulefile}{$sid}{'State'} = "off";
1228                                 } else {
1229                                         # Otherwise the rule is enabled.
1230                                         $idsrules{$rulefile}{$sid}{'State'} = "on";
1231                                 }
1232                         }
1233                 }
1234         }
1235 }
1236
1237 #
1238 ## Function to get the used memory of a given process-id.
1239 #
1240 sub get_memory_usage($) {
1241         my ($pid) = @_;
1242
1243         my $memory = 0;
1244
1245         # Try to open the status file for the given process-id on the pseudo
1246         # file system proc.
1247         if (open(FILE, "/proc/$pid/status")) {
1248                 # Loop through the entire file.
1249                 while (<FILE>) {
1250                         # Splitt current line content and store them into variables.
1251                         my ($key, $value) = split(":", $_, 2);
1252
1253                         # Check if the current key is the one which contains the memory usage.
1254                         # The wanted one is VmRSS which contains the Real-memory (resident set)
1255                         # of the entire process.
1256                         if ($key eq "VmRSS") {
1257                                 # Found the memory usage add it to the memory variable.
1258                                 $memory += $value;
1259
1260                                 # Break the loop.
1261                                 last;
1262                         }
1263                 }
1264
1265                 # Close file handle.
1266                 close(FILE);
1267
1268                 # Return memory usage.
1269                 return $memory;
1270         }
1271
1272         # If the file could not be open, return nothing.
1273         return;
1274 }
1275
1276 #
1277 ## Function to read-in the given enabled or disables sids file.
1278 #
1279 sub read_enabled_disabled_sids_file($) {
1280         my ($file) = @_;
1281
1282         # Temporary hash to store the sids and their state. It will be
1283         # returned at the end of this function.
1284         my %temphash;
1285
1286         # Open the given filename.
1287         open(FILE, "$file") or die "Could not open $file. $!\n";
1288
1289         # Loop through the file.
1290         while(<FILE>) {
1291                 # Remove newlines.
1292                 chomp $_;
1293
1294                 # Skip blank lines.
1295                 next if ($_ =~ /^\s*$/);
1296
1297                 # Skip coments.
1298                 next if ($_ =~ /^\#/);
1299
1300                 # Splitt line into sid and state part.
1301                 my ($state, $sid) = split(" ", $_);
1302
1303                 # Skip line if the sid is not numeric.
1304                 next unless ($sid =~ /\d+/ );
1305
1306                 # Check if the sid was enabled.
1307                 if ($state eq "enablesid") {
1308                         # Add the sid and its state as enabled to the temporary hash.
1309                         $temphash{$sid} = "enabled";
1310                 # Check if the sid was disabled.
1311                 } elsif ($state eq "disablesid") {
1312                         # Add the sid and its state as disabled to the temporary hash.
1313                         $temphash{$sid} = "disabled";
1314                 # Invalid state - skip the current sid and state.
1315                 } else {
1316                         next;
1317                 }
1318         }
1319
1320         # Close filehandle.
1321         close(FILE);
1322
1323         # Return the hash.
1324         return %temphash;
1325 }
1326
1327 #
1328 ## Private function to convert a given rulefile to a category name.
1329 ## ( No file extension anymore and if the name contained a dot, it
1330 ## would be replaced by a underline sign.)
1331 #
1332 sub _rulefile_to_category($) {
1333         my ($filename) = @_;
1334
1335         # Splitt the filename into single chunks and store them in a
1336         # temorary array.
1337         my @parts = split(/\./, $filename);
1338
1339         # Return / Remove last element of the temporary array.
1340         # This removes the file extension.
1341         pop @parts;
1342
1343         # Join together the single elements of the temporary array.
1344         # If these are more than one, use a "underline" for joining.
1345         my $category = join '_', @parts;
1346
1347         # Return the converted filename.
1348         return $category;
1349 }