config/cfgroot/ids-functions.pl

   1 #!/usr/bin/perl -w
   2 ############################################################################
   3 #                                                                          #
   4 # This file is part of the IPFire Firewall.                                #
   5 #                                                                          #
   6 # IPFire is free software; you can redistribute it and/or modify           #
   7 # it under the terms of the GNU General Public License as published by     #
   8 # the Free Software Foundation; either version 2 of the License, or        #
   9 # (at your option) any later version.                                      #
  10 #                                                                          #
  11 # IPFire is distributed in the hope that it will be useful,                #
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of           #
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the            #
  14 # GNU General Public License for more details.                             #
  15 #                                                                          #
  16 # You should have received a copy of the GNU General Public License        #
  17 # along with IPFire; if not, write to the Free Software                    #
  18 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA #
  19 #                                                                          #
  20 # Copyright (C) 2018-2019 IPFire Team <info@ipfire.org>                    #
  21 #                                                                          #
  22 ############################################################################
  23
  24 use strict;
  25
  26 package IDS;
  27
  28 require '/var/ipfire/general-functions.pl';
  29 require "${General::swroot}/network-functions.pl";
  30 require "${General::swroot}/suricata/ruleset-sources";
  31
  32 # Location where all config and settings files are stored.
  33 our $settingsdir = "${General::swroot}/suricata";
  34
  35 # File where the main file for providers ruleset inclusion exists.
  36 our $suricata_used_providers_file = "$settingsdir/suricata-used-providers.yaml";
  37
  38 # File for static ruleset inclusions.
  39 our $suricata_default_rulefiles_file = "$settingsdir/suricata-default-rules.yaml";
  40
  41 # File where the addresses of the homenet are stored.
  42 our $homenet_file = "$settingsdir/suricata-homenet.yaml";
  43
  44 # File where the addresses of the used DNS servers are stored.
  45 our $dns_servers_file = "$settingsdir/suricata-dns-servers.yaml";
  46
  47 # File where the HTTP ports definition is stored.
  48 our $http_ports_file = "$settingsdir/suricata-http-ports.yaml";
  49
  50 # File which contains includes for provider specific rule modifications.
  51 our $oinkmaster_provider_includes_file = "$settingsdir/oinkmaster-provider-includes.conf";
  52
  53 # File which contains wheater the rules should be changed.
  54 our $modify_sids_file = "$settingsdir/oinkmaster-modify-sids.conf";
  55
  56 # File which stores the configured IPS settings.
  57 our $ids_settings_file = "$settingsdir/settings";
  58
  59 # File which stores the used and configured ruleset providers.
  60 our $providers_settings_file = "$settingsdir/providers-settings";
  61
  62 # File which stores the configured settings for whitelisted addresses.
  63 our $ignored_file = "$settingsdir/ignored";
  64
  65 # Location where the downloaded rulesets are stored.
  66 our $dl_rules_path = "/var/tmp";
  67
  68 # File to store any errors, which also will be read and displayed by the wui.
  69 our $storederrorfile = "/tmp/ids_storederror";
  70
  71 # File to lock the WUI, while the autoupdate script runs.
  72 our $ids_page_lock_file = "/tmp/ids_page_locked";
  73
  74 # Location where the rulefiles are stored.
  75 our $rulespath = "/var/lib/suricata";
  76
  77 # Location where the default rulefils are stored.
  78 our $default_rulespath = "/usr/share/suricata/rules";
  79
  80 # Location where the addition config files are stored.
  81 our $configspath = "/usr/share/suricata";
  82
  83 # Location of the classification file.
  84 our $classification_file = "$configspath/classification.config";
  85
  86 # Location of the sid to msg mappings file.
  87 our $sid_msg_file = "$rulespath/sid-msg.map";
  88
  89 # Location to store local rules. This file will not be touched.
  90 our $local_rules_file = "$rulespath/local.rules";
  91
  92 # File which contains the rules to whitelist addresses on suricata.
  93 our $whitelist_file = "$rulespath/whitelist.rules";
  94
  95 # File which contains a list of all supported ruleset sources.
  96 # (Sourcefire, Emergingthreads, etc..)
  97 our $rulesetsourcesfile = "$settingsdir/ruleset-sources";
  98
  99 # The pidfile of the IDS.
 100 our $idspidfile = "/var/run/suricata.pid";
 101
 102 # Location of suricatactrl.
 103 my $suricatactrl = "/usr/local/bin/suricatactrl";
 104
 105 # Prefix for each downloaded ruleset.
 106 my $dl_rulesfile_prefix = "idsrules";
 107
 108 # Temporary directory where the rulesets will be extracted.
 109 my $tmp_directory = "/tmp/ids_tmp";
 110
 111 # Temporary directory where the extracted rules files will be stored.
 112 my $tmp_rules_directory = "$tmp_directory/rules";
 113
 114 # Temporary directory where the extracted additional config files will be stored.
 115 my $tmp_conf_directory = "$tmp_directory/conf";
 116
 117 # Array with allowed commands of suricatactrl.
 118 my @suricatactrl_cmds = ( 'start', 'stop', 'restart', 'reload', 'fix-rules-dir', 'cron' );
 119
 120 # Array with supported cron intervals.
 121 my @cron_intervals = ('off', 'daily', 'weekly' );
 122
 123 # Array which contains the HTTP ports, which statically will be declared as HTTP_PORTS in the
 124 # http_ports_file.
 125 my @http_ports = ('80', '81');
 126
 127 # Array which contains a list of rulefiles which always will be included if they exist.
 128 my @static_included_rulefiles = ('local.rules', 'whitelist.rules');
 129
 130 # Array which contains a list of allways enabled application layer protocols.
 131 my @static_enabled_app_layer_protos = ('app-layer', 'decoder', 'files', 'stream');
 132
 133 # Hash which allows to convert the download type (dl_type) to a file suffix.
 134 my %dl_type_to_suffix = (
 135         "archive" => ".tar.gz",
 136         "plain" => ".rules",
 137 );
 138
 139 # Hash to translate an application layer protocol to the application name.
 140 my %tr_app_layer_proto = (
 141         "ikev2" => "ipsec",
 142         "krb5" => "kerberos",
 143 );
 144
 145 #
 146 ## Function to check and create all IDS related files, if the does not exist.
 147 #
 148 sub check_and_create_filelayout() {
 149         # Check if the files exist and if not, create them.
 150         unless (-f "$oinkmaster_provider_includes_file") { &create_empty_file($oinkmaster_provider_includes_file); }
 151         unless (-f "$modify_sids_file") { &create_empty_file($modify_sids_file); }
 152         unless (-f "$suricata_used_providers_file") { &create_empty_file($suricata_used_providers_file); }
 153         unless (-f "$suricata_default_rulefiles_file") { &create_empty_file($suricata_default_rulefiles_file); }
 154         unless (-f "$ids_settings_file") { &create_empty_file($ids_settings_file); }
 155         unless (-f "$providers_settings_file") { &create_empty_file($providers_settings_file); }
 156         unless (-f "$whitelist_file" ) { &create_empty_file($whitelist_file); }
 157 }
 158
 159 #
 160 ## Function to get a list of all available ruleset providers.
 161 ##
 162 ## They will be returned as a sorted array.
 163 #
 164 sub get_ruleset_providers() {
 165         my @providers;
 166
 167         # Loop through the hash of providers.
 168         foreach my $provider ( keys %IDS::Ruleset::Providers ) {
 169                 # Add the provider to the array.
 170                 push(@providers, $provider);
 171         }
 172
 173         # Sort and return the array.
 174         return sort(@providers);
 175 }
 176
 177 #
 178 ## Function to get a list of all enabled ruleset providers.
 179 ##
 180 ## They will be returned as an array.
 181 #
 182 sub get_enabled_providers () {
 183         my %used_providers = ();
 184
 185         # Array to store the enabled providers.
 186         my @enabled_providers = ();
 187
 188         # Read-in the providers config file.
 189         &General::readhasharray("$providers_settings_file", \%used_providers);
 190
 191         # Loop through the hash of used_providers.
 192         foreach my $id (keys %used_providers) {
 193                 # Skip disabled providers.
 194                 next unless ($used_providers{$id}[3] eq "enabled");
 195
 196                 # Grab the provider handle.
 197                 my $provider = "$used_providers{$id}[0]";
 198
 199                 # Add the provider to the array of enabled providers.
 200                 push(@enabled_providers, $provider);
 201         }
 202
 203         # Return the array.
 204         return @enabled_providers;
 205 }
 206
 207 #
 208 ## Function for checking if at least 300MB of free disk space are available
 209 ## on the "/var" partition.
 210 #
 211 sub checkdiskspace () {
 212         # Call diskfree to gather the free disk space of /var.
 213         my @df = &General::system_output("/bin/df", "-B", "M", "/var");
 214
 215         # Loop through the output.
 216         foreach my $line (@df) {
 217                 # Ignore header line.
 218                 next if $line =~ m/^Filesystem/;
 219
 220                 # Search for a line with the device information.
 221                 if ($line =~ m/dev/ ) {
 222                         # Split the line into single pieces.
 223                         my @values = split(' ', $line);
 224                         my ($filesystem, $blocks, $used, $available, $used_perenctage, $mounted_on) = @values;
 225
 226                         # Check if the available disk space is more than 300MB.
 227                         if ($available < 300) {
 228                                 # Log error to syslog.
 229                                 &_log_to_syslog("Not enough free disk space on /var. Only $available MB from 300 MB available.");
 230
 231                                 # Exit function and return "1" - False.
 232                                 return 1;
 233                         }
 234                 }
 235         }
 236
 237         # Everything okay, return nothing.
 238         return;
 239 }
 240
 241 #
 242 ## This function is responsible for downloading the configured IDS rulesets or if no one is specified
 243 ## all configured rulesets will be downloaded.
 244 ##
 245 ## * At first it gathers all configured ruleset providers, initialize the downloader and sets an
 246 ##   upstream proxy if configured.
 247 ## * After that, the given ruleset or in case all rulesets should be downloaded, it will determine wether it
 248 ##   is enabled or not.
 249 ## * The next step will be to generate the final download url, by obtaining the URL for the desired
 250 ##   ruleset, add the settings for the upstream proxy.
 251 ## * Finally the function will grab all the rules files or tarballs from the servers.
 252 #
 253 sub downloadruleset ($) {
 254         my ($provider) = @_;
 255
 256         # If no provider is given default to "all".
 257         $provider //= 'all';
 258
 259         # Hash to store the providers and access id's, for which rules should be downloaded.
 260         my %sheduled_providers = ();
 261
 262         # Get used provider settings.
 263         my %used_providers = ();
 264         &General::readhasharray("$providers_settings_file", \%used_providers);
 265
 266         # Check if a ruleset has been configured.
 267         unless(%used_providers) {
 268                 # Log that no ruleset has been configured and abort.
 269                 &_log_to_syslog("No ruleset provider has been configured.");
 270
 271                 # Return "1".
 272                 return 1;
 273         }
 274
 275         # Read proxysettings.
 276         my %proxysettings=();
 277         &General::readhash("${General::swroot}/proxy/settings", \%proxysettings);
 278
 279         # Load required perl module to handle the download.
 280         use LWP::UserAgent;
 281
 282         # Init the download module.
 283         #
 284         # Request SSL hostname verification and specify path
 285         # to the CA file.
 286         my $downloader = LWP::UserAgent->new(
 287                 ssl_opts => {
 288                         SSL_ca_file     => '/etc/ssl/cert.pem',
 289                         verify_hostname => 1,
 290                 }
 291         );
 292
 293         # Set timeout to 10 seconds.
 294         $downloader->timeout(10);
 295
 296         # Check if an upstream proxy is configured.
 297         if ($proxysettings{'UPSTREAM_PROXY'}) {
 298                 my $proxy_url;
 299
 300                 $proxy_url = "http://";
 301
 302                 # Check if the proxy requires authentication.
 303                 if (($proxysettings{'UPSTREAM_USER'}) && ($proxysettings{'UPSTREAM_PASSWORD'})) {
 304                         $proxy_url .= "$proxysettings{'UPSTREAM_USER'}\:$proxysettings{'UPSTREAM_PASSWORD'}\@";
 305                 }
 306
 307                 # Add proxy server address and port.
 308                 $proxy_url .= $proxysettings{'UPSTREAM_PROXY'};
 309
 310                 # Setup proxy settings.
 311                 $downloader->proxy(['http', 'https'], $proxy_url);
 312         }
 313
 314         # Loop through the hash of configured providers.
 315         foreach my $id ( keys %used_providers ) {
 316                 # Skip providers which are not enabled.
 317                 next if ($used_providers{$id}[3] ne "enabled");
 318
 319                 # Obtain the provider handle.
 320                 my $provider_handle = $used_providers{$id}[0];
 321
 322                 # Handle update off all providers.
 323                 if (($provider eq "all") || ($provider_handle eq "$provider")) {
 324                         # Add provider handle and it's id to the hash of sheduled providers.
 325                         $sheduled_providers{$provider_handle} = $id;
 326                 }
 327         }
 328
 329         # Loop through the hash of sheduled providers.
 330         foreach my $provider ( keys %sheduled_providers) {
 331                 # Log download/update of the ruleset.
 332                 &_log_to_syslog("Downloading ruleset for provider: $provider.");
 333
 334                 # Grab the download url for the provider.
 335                 my $url = $IDS::Ruleset::Providers{$provider}{'dl_url'};
 336
 337                 # Check if the provider requires a subscription.
 338                 if ($IDS::Ruleset::Providers{$provider}{'requires_subscription'} eq "True") {
 339                         # Grab the previously stored access id for the provider from hash.
 340                         my $id = $sheduled_providers{$provider};
 341
 342                         # Grab the subscription code.
 343                         my $subscription_code = $used_providers{$id}[1];
 344
 345                         # Add the subscription code to the download url.
 346                         $url =~ s/\<subscription_code\>/$subscription_code/g;
 347
 348                 }
 349
 350                 # Abort if no url could be determined for the provider.
 351                 unless ($url) {
 352                         # Log error and abort.
 353                         &_log_to_syslog("Unable to gather a download URL for the selected ruleset provider.");
 354                         return 1;
 355                 }
 356
 357                 # Variable to store the filesize of the remote object.
 358                 my $remote_filesize;
 359
 360                 # The sourcfire (snort rules) does not allow to send "HEAD" requests, so skip this check
 361                 # for this webserver.
 362                 #
 363                 # Check if the ruleset source contains "snort.org".
 364                 unless ($url =~ /\.snort\.org/) {
 365                         # Pass the requrested url to the downloader.
 366                         my $request = HTTP::Request->new(HEAD => $url);
 367
 368                         # Accept the html header.
 369                         $request->header('Accept' => 'text/html');
 370
 371                         # Perform the request and fetch the html header.
 372                         my $response = $downloader->request($request);
 373
 374                         # Check if there was any error.
 375                         unless ($response->is_success) {
 376                                 # Obtain error.
 377                                 my $error = $response->status_line();
 378
 379                                 # Log error message.
 380                                 &_log_to_syslog("Unable to download the ruleset. \($error\)");
 381
 382                                 # Return "1" - false.
 383                                 return 1;
 384                         }
 385
 386                         # Assign the fetched header object.
 387                         my $header = $response->headers();
 388
 389                         # Grab the remote file size from the object and store it in the
 390                         # variable.
 391                         $remote_filesize = $header->content_length;
 392                 }
 393
 394                 # Load perl module to deal with temporary files.
 395                 use File::Temp;
 396
 397                 # Generate temporary file name, located in "/var/tmp" and with a suffix of ".tmp".
 398                 my $tmp = File::Temp->new( SUFFIX => ".tmp", DIR => "/var/tmp/", UNLINK => 0 );
 399                 my $tmpfile = $tmp->filename();
 400
 401                 # Pass the requested url to the downloader.
 402                 my $request = HTTP::Request->new(GET => $url);
 403
 404                 # Perform the request and save the output into the tmpfile.
 405                 my $response = $downloader->request($request, $tmpfile);
 406
 407                 # Check if there was any error.
 408                 unless ($response->is_success) {
 409                         # Obtain error.
 410                         my $error = $response->content;
 411
 412                         # Log error message.
 413                         &_log_to_syslog("Unable to download the ruleset. \($error\)");
 414
 415                         # Return "1" - false.
 416                         return 1;
 417                 }
 418
 419                 # Load perl stat module.
 420                 use File::stat;
 421
 422                 # Perform stat on the tmpfile.
 423                 my $stat = stat($tmpfile);
 424
 425                 # Grab the local filesize of the downloaded tarball.
 426                 my $local_filesize = $stat->size;
 427
 428                 # Check if both file sizes match.
 429                 if (($remote_filesize) && ($remote_filesize ne $local_filesize)) {
 430                         # Log error message.
 431                         &_log_to_syslog("Unable to completely download the ruleset. ");
 432                         &_log_to_syslog("Only got $local_filesize Bytes instead of $remote_filesize Bytes. ");
 433
 434                         # Delete temporary file.
 435                         unlink("$tmpfile");
 436
 437                         # Return "1" - false.
 438                         return 1;
 439                 }
 440
 441                 # Genarate and assign file name and path to store the downloaded rules file.
 442                 my $dl_rulesfile = &_get_dl_rulesfile($provider);
 443
 444                 # Check if a file name could be obtained.
 445                 unless ($dl_rulesfile) {
 446                         # Log error message.
 447                         &_log_to_syslog("Unable to store the downloaded rules file. ");
 448
 449                         # Delete downloaded temporary file.
 450                         unlink("$tmpfile");
 451
 452                         # Return "1" - false.
 453                         return 1;
 454                 }
 455
 456                 # Load file copy module, which contains the move() function.
 457                 use File::Copy;
 458
 459                 # Overwrite the may existing rulefile or tarball with the downloaded one.
 460                 move("$tmpfile", "$dl_rulesfile");
 461
 462                 # Delete temporary file.
 463                 unlink("$tmpfile");
 464
 465                 # Set correct ownership for the tarball.
 466                 set_ownership("$dl_rulesfile");
 467         }
 468
 469         # If we got here, everything worked fine. Return nothing.
 470         return;
 471 }
 472
 473 #
 474 ## Function to extract a given ruleset.
 475 ##
 476 ## In case the ruleset provider offers a plain file, it simply will
 477 ## be copied.
 478 #
 479 sub extractruleset ($) {
 480         my ($provider) = @_;
 481
 482         # Load perl module to deal with archives.
 483         use Archive::Tar;
 484
 485         # Disable chown functionality when uncompressing files.
 486         $Archive::Tar::CHOWN = "0";
 487
 488         # Load perl module to deal with files and path.
 489         use File::Basename;
 490
 491         # Load perl module for file copying.
 492         use File::Copy;
 493
 494         # Get full path and downloaded rulesfile for the given provider.
 495         my $tarball = &_get_dl_rulesfile($provider);
 496
 497         # Check if the file exists.
 498         unless (-f $tarball) {
 499                 &_log_to_syslog("Could not find ruleset file: $tarball");
 500
 501                 # Return nothing.
 502                 return;
 503         }
 504
 505         # Check if the temporary directories exist, otherwise create them.
 506         mkdir("$tmp_directory") unless (-d "$tmp_directory");
 507         mkdir("$tmp_rules_directory") unless (-d "$tmp_rules_directory");
 508         mkdir("$tmp_conf_directory") unless (-d "$tmp_conf_directory");
 509
 510         # Omit the type (dl_type) of the stored ruleset.
 511         my $type = $IDS::Ruleset::Providers{$provider}{'dl_type'};
 512
 513         # Handle the different ruleset types.
 514         if ($type eq "plain") {
 515                 # Generate destination filename an full path.
 516                 my $destination = "$tmp_rules_directory/$provider\-ruleset.rules";
 517
 518                 # Copy the file into the temporary rules directory.
 519                 copy($tarball, $destination);
 520
 521         } elsif ( $type eq "archive") {
 522                 # Initialize the tar module.
 523                 my $tar = Archive::Tar->new($tarball);
 524
 525                 # Get the filelist inside the tarball.
 526                 my @packed_files = $tar->list_files;
 527
 528                 # Loop through the filelist.
 529                 foreach my $packed_file (@packed_files) {
 530                         my $destination;
 531
 532                         # Splitt the packed file into chunks.
 533                         my $file = fileparse($packed_file);
 534
 535                         # Handle msg-id.map file.
 536                         if ("$file" eq "sid-msg.map") {
 537                                 # Set extract destination to temporary config_dir.
 538                                 $destination = "$tmp_conf_directory/$provider\-sid-msg.map";
 539
 540                         # Handle classification.conf
 541                         } elsif ("$file" eq "classification.config") {
 542                                 # Set extract destination to temporary config_dir.
 543                                 $destination = "$tmp_conf_directory/$provider\-classification.config";
 544
 545                         # Handle rules files.
 546                         } elsif ($file =~ m/\.rules$/) {
 547                                 # Skip rule files which are not located in the rules directory or archive root.
 548                                 next unless(($packed_file =~ /^rules\//) || ($packed_file !~ /\//));
 549
 550                                 # Skip deleted.rules.
 551                                 #
 552                                 # Mostly they have been taken out for correctness or performance reasons and therfore
 553                                 # it is not a great idea to enable any of them.
 554                                 next if($file =~ m/deleted.rules$/);
 555
 556                                 my $rulesfilename;
 557
 558                                 # Splitt the filename into chunks.
 559                                 my @filename = split("-", $file);
 560
 561                                 # Reverse the array.
 562                                 @filename = reverse(@filename);
 563
 564                                 # Get the amount of elements in the array.
 565                                 my $elements = @filename;
 566
 567                                 # Remove last element of the hash.
 568                                 # It contains the vendor name, which will be replaced.
 569                                 if ($elements >= 3) {
 570                                 # Remove last element from hash.
 571                                         pop(@filename);
 572                                 }
 573
 574                                 # Check if the last element of the filename does not
 575                                 # contain the providers name.
 576                                 if ($filename[-1] ne "$provider") {
 577                                         # Add provider name as last element.
 578                                         push(@filename, $provider);
 579                                 }
 580
 581                                 # Reverse the array back.
 582                                 @filename = reverse(@filename);
 583
 584                                 # Generate the name for the rulesfile.
 585                                 $rulesfilename = join("-", @filename);
 586
 587                                 # Set extract destination to temporaray rules_dir.
 588                                 $destination = "$tmp_rules_directory/$rulesfilename";
 589                         } else {
 590                                 # Skip all other files.
 591                                 next;
 592                         }
 593
 594                         # Check if the destination file exists.
 595                         unless(-e "$destination") {
 596                                 # Extract the file to the temporary directory.
 597                                 $tar->extract_file("$packed_file", "$destination");
 598                         } else {
 599                                 # Load perl module to deal with temporary files.
 600                                 use File::Temp;
 601
 602                                 # Generate temporary file name, located in the temporary rules directory and a suffix of ".tmp".
 603                                 my $tmp = File::Temp->new( SUFFIX => ".tmp", DIR => "$tmp_rules_directory", UNLINK => 0 );
 604                                 my $tmpfile = $tmp->filename();
 605
 606                                 # Extract the file to the new temporary file name.
 607                                 $tar->extract_file("$packed_file", "$tmpfile");
 608
 609                                 # Open the the existing file.
 610                                 open(DESTFILE, ">>", "$destination") or die "Could not open $destination. $!\n";
 611                                 open(TMPFILE, "<", "$tmpfile") or die "Could not open $tmpfile. $!\n";
 612
 613                                 # Loop through the content of the temporary file.
 614                                 while (<TMPFILE>) {
 615                                         # Append the content line by line to the destination file.
 616                                         print DESTFILE "$_";
 617                                 }
 618
 619                                 # Close the file handles.
 620                                 close(TMPFILE);
 621                                 close(DESTFILE);
 622
 623                                 # Remove the temporary file.
 624                                 unlink("$tmpfile");
 625                         }
 626                 }
 627         }
 628 }
 629
 630 #
 631 ## A wrapper function to call the oinkmaster script, setup the rules structues and
 632 ## call the functions to merge the additional config files. (classification, sid-msg, etc.).
 633 #
 634 sub oinkmaster () {
 635         # Check if the files in rulesdir have the correct permissions.
 636         &_check_rulesdir_permissions();
 637
 638         # Cleanup the rules directory before filling it with the new rulests.
 639         &_cleanup_rulesdir();
 640
 641         # Get all enabled providers.
 642         my @enabled_providers = &get_enabled_providers();
 643
 644         # Loop through the array of enabled providers.
 645         foreach my $provider (@enabled_providers) {
 646                 # Call the extractruleset function.
 647                 &extractruleset($provider);
 648         }
 649
 650         # Load perl module to talk to the kernel syslog.
 651         use Sys::Syslog qw(:DEFAULT setlogsock);
 652
 653         # Establish the connection to the syslog service.
 654         openlog('oinkmaster', 'cons,pid', 'user');
 655
 656         # Call oinkmaster to generate ruleset.
 657         open(OINKMASTER, "/usr/local/bin/oinkmaster.pl -s -u dir://$tmp_rules_directory -C $settingsdir/oinkmaster.conf -o $rulespath 2>&1 |") or die "Could not execute oinkmaster $!\n";
 658
 659         # Log output of oinkmaster to syslog.
 660         while(<OINKMASTER>) {
 661                 # The syslog function works best with an array based input,
 662                 # so generate one before passing the message details to syslog.
 663                 my @syslog = ("INFO", "$_");
 664
 665                 # Send the log message.
 666                 syslog(@syslog);
 667         }
 668
 669         # Close the pipe to oinkmaster process.
 670         close(OINKMASTER);
 671
 672         # Close the log handle.
 673         closelog();
 674
 675         # Call function to merge the classification files.
 676         &merge_classifications(@enabled_providers);
 677
 678         # Call function to merge the sid to message mapping files.
 679         &merge_sid_msg(@enabled_providers);
 680
 681         # Cleanup temporary directory.
 682         &cleanup_tmp_directory();
 683 }
 684
 685 #
 686 ## Function to merge the classifications for a given amount of providers and write them
 687 ## to the classifications file.
 688 #
 689 sub merge_classifications(@) {
 690         my @providers = @_;
 691
 692         # Hash to store all collected classifications.
 693         my %classifications = ();
 694
 695         # Loop through the given array of providers.
 696         foreach my $provider (@providers) {
 697                 # Generate full path to classification file.
 698                 my $classification_file = "$tmp_conf_directory/$provider\-classification.config";
 699
 700                 # Skip provider if no classification file exists.
 701                 next unless (-f "$classification_file");
 702
 703                 # Open the classification file.
 704                 open(CLASSIFICATION, $classification_file) or die "Could not open file $classification_file. $!\n";
 705
 706                 # Loop through the file content.
 707                 while(<CLASSIFICATION>) {
 708                         # Parse the file and grab the classification details.
 709                         if ($_ =~/.*config classification\: (.*)/) {
 710                                 # Split the grabbed details.
 711                                 my ($short_name, $short_desc, $priority) = split("\,", $1);
 712
 713                                 # Check if the grabbed classification is allready known and the priority value is greater
 714                                 # than the stored one (which causes less priority in the IDS).
 715                                 if (($classifications{$short_name}) && ($classifications{$short_name}[1] >= $priority)) {
 716                                         #Change the priority value to the stricter one.
 717                                         $classifications{$short_name} = [ "$classifications{$short_name}[0]", "$priority" ];
 718                                 } else {
 719                                         # Add the classification to the hash.
 720                                         $classifications{$short_name} = [ "$short_desc", "$priority" ];
 721                                 }
 722                         }
 723                 }
 724
 725                 # Close the file.
 726                 close(CLASSIFICATION);
 727         }
 728
 729         # Open classification file for writing.
 730         open(FILE, ">", "$classification_file") or die "Could not write to $classification_file. $!\n";
 731
 732         # Print notice about autogenerated file.
 733         print FILE "#Autogenerated file. Any custom changes will be overwritten!\n\n";
 734
 735         # Sort and loop through the hash of classifications.
 736         foreach my $key (sort keys %classifications) {
 737                 # Assign some nice variable names for the items.
 738                 my $short_name = $key;
 739                 my $short_desc = $classifications{$key}[0];
 740                 my $priority = $classifications{$key}[1];
 741
 742                 # Write the classification to the file.
 743                 print FILE "config classification: $short_name,$short_desc,$priority\n";
 744         }
 745
 746         # Close file handle.
 747         close(FILE);
 748 }
 749
 750 #
 751 ## Function to merge the "sid to message mapping" files of various given providers.
 752 #
 753 sub merge_sid_msg (@) {
 754         my @providers = @_;
 755
 756         # Hash which contains all the sid to message mappings.
 757         my %mappings = ();
 758
 759         # Loop through the array of given providers.
 760         foreach my $provider (@providers) {
 761                 # Generate full path and filename.
 762                 my $sid_msg_file = "$tmp_conf_directory/$provider\-sid-msg.map";
 763
 764                 # Skip provider if no sid to msg mapping file for this provider exists.
 765                 next unless (-f $sid_msg_file);
 766
 767                 # Open the file.
 768                 open(MAPPING, $sid_msg_file) or die "Could not open $sid_msg_file. $!\n";
 769
 770                 # Loop through the file content.
 771                 while (<MAPPING>) {
 772                         # Remove newlines.
 773                         chomp($_);
 774
 775                         # Skip lines which do not start with a number,
 776                         next unless ($_ =~ /^\d+/);
 777
 778                         # Split line content and assign it to an array.
 779                         my @line = split(/ \|\| /, $_);
 780
 781                         # Grab the first element (and remove it) from the line array.
 782                         # It contains the sid.
 783                         my $sid = shift(@line);
 784
 785                         # Store the grabbed sid and the remain array as hash value.
 786                         # It still contains the messages, references etc.
 787                         $mappings{$sid} = [@line];
 788                 }
 789
 790                 # Close file handle.
 791                 close(MAPPING);
 792         }
 793
 794         # Open mappings file for writing.
 795         open(FILE, ">", $sid_msg_file) or die "Could not write $sid_msg_file. $!\n";
 796
 797         # Write notice about autogenerated file.
 798         print FILE "#Autogenerated file. Any custom changes will be overwritten!\n\n";
 799
 800         # Loop through the hash of mappings.
 801         foreach my $sid ( sort keys %mappings) {
 802                 # Grab data for the sid.
 803                 my @data = @{$mappings{$sid}};
 804
 805                 # Add the sid to the data array.
 806                 unshift(@data, $sid);
 807
 808                 # Generate line.
 809                 my $line = join(" \|\| ", @data);
 810
 811                 print FILE "$line\n";
 812
 813         }
 814
 815         # Close file handle.
 816         close(FILE);
 817 }
 818
 819 #
 820 ## A very tiny function to move an extracted ruleset from the temporary directory into
 821 ## the rules directory.
 822 #
 823 sub move_tmp_ruleset() {
 824         # Load perl module.
 825         use File::Copy;
 826
 827         # Do a directory listing of the temporary directory.
 828         opendir  DH, $tmp_rules_directory;
 829
 830         # Loop over all files.
 831         while(my $file = readdir DH) {
 832                 # Move them to the rules directory.
 833                 move "$tmp_rules_directory/$file" , "$rulespath/$file";
 834         }
 835
 836         # Close directory handle.
 837         closedir DH;
 838 }
 839
 840 #
 841 ## Function to cleanup the temporary IDS directroy.
 842 #
 843 sub cleanup_tmp_directory () {
 844         # Load rmtree() function from file path perl module.
 845         use File::Path 'rmtree';
 846
 847         # Delete temporary directory and all containing files.
 848         rmtree([ "$tmp_directory" ]);
 849 }
 850
 851 #
 852 ## Function to do all the logging stuff if the downloading or updating of the ruleset fails.
 853 #
 854 sub log_error ($) {
 855         my ($error) = @_;
 856
 857         # Remove any newline.
 858         chomp($error);
 859
 860         # Call private function to log the error message to syslog.
 861         &_log_to_syslog($error);
 862
 863         # Call private function to write/store the error message in the storederrorfile.
 864         &_store_error_message($error);
 865 }
 866
 867 #
 868 ## Function to log a given error message to the kernel syslog.
 869 #
 870 sub _log_to_syslog ($) {
 871         my ($message) = @_;
 872
 873         # Load perl module to talk to the kernel syslog.
 874         use Sys::Syslog qw(:DEFAULT setlogsock);
 875
 876         # The syslog function works best with an array based input,
 877         # so generate one before passing the message details to syslog.
 878         my @syslog = ("ERR", "<ERROR> $message");
 879
 880         # Establish the connection to the syslog service.
 881         openlog('oinkmaster', 'cons,pid', 'user');
 882
 883         # Send the log message.
 884         syslog(@syslog);
 885
 886         # Close the log handle.
 887         closelog();
 888 }
 889
 890 #
 891 ## Private function to write a given error message to the storederror file.
 892 #
 893 sub _store_error_message ($) {
 894         my ($message) = @_;
 895
 896         # Remove any newline.
 897         chomp($message);
 898
 899         # Open file for writing.
 900         open (ERRORFILE, ">$storederrorfile") or die "Could not write to $storederrorfile. $!\n";
 901
 902         # Write error to file.
 903         print ERRORFILE "$message\n";
 904
 905         # Close file.
 906         close (ERRORFILE);
 907
 908         # Set correct ownership for the file.
 909         &set_ownership("$storederrorfile");
 910 }
 911
 912 #
 913 ## Private function to get the path and filename for a downloaded ruleset by a given provider.
 914 #
 915 sub _get_dl_rulesfile($) {
 916         my ($provider) = @_;
 917
 918         # Gather the download type for the given provider.
 919         my $dl_type = $IDS::Ruleset::Providers{$provider}{'dl_type'};
 920
 921         # Obtain the file suffix for the download file type.
 922         my $suffix = $dl_type_to_suffix{$dl_type};
 923
 924         # Check if a suffix has been found.
 925         unless ($suffix) {
 926                 # Abort return - nothing.
 927                 return;
 928         }
 929
 930         # Generate the full filename and path for the stored rules file.
 931         my $rulesfile = "$dl_rules_path/$dl_rulesfile_prefix-$provider$suffix";
 932
 933         # Return the generated filename.
 934         return $rulesfile;
 935 }
 936
 937 #
 938 ## Tiny function to delete the stored ruleset file or tarball for a given provider.
 939 #
 940 sub drop_dl_rulesfile ($) {
 941         my ($provider) = @_;
 942
 943         # Gather the full path and name of the stored rulesfile.
 944         my $rulesfile = &_get_dl_rulesfile($provider);
 945
 946         # Check if the given rulesfile exists.
 947         if (-f $rulesfile) {
 948                 # Delete the stored rulesfile.
 949                 unlink($rulesfile) or die "Could not delete $rulesfile. $!\n";
 950         }
 951 }
 952
 953 #
 954 ## Tiny function to get/generate the full path and filename for the providers oinkmaster
 955 ## modified sids file.
 956 #
 957 sub get_oinkmaster_provider_modified_sids_file ($) {
 958         my ($provider) = @_;
 959
 960         # Generate the filename.
 961         my $filename = "$settingsdir/oinkmaster-$provider-modified-sids.conf";
 962
 963         # Return the filename.
 964         return $filename;
 965 }
 966
 967 #
 968 ## Function to directly altering the oinkmaster provider includes file.
 969 ##
 970 ## Requires tha acition "remove" or "add" and a provider handle.
 971 #
 972 sub alter_oinkmaster_provider_includes_file ($$) {
 973         my ($action, $provider) = @_;
 974
 975         # Call function to get the path and name for the given providers
 976         # oinkmaster modified sids file.
 977         my $provider_modified_sids_file = &get_oinkmaster_provider_modified_sids_file($provider);
 978
 979         # Open the file for reading..
 980         open (FILE, $oinkmaster_provider_includes_file) or die "Could not read $oinkmaster_provider_includes_file. $!\n";
 981
 982         # Read-in file content.
 983         my @lines = <FILE>;
 984
 985         # Close file after reading.
 986         close(FILE);
 987
 988         # Re-open the file for writing.
 989         open(FILE, ">", $oinkmaster_provider_includes_file) or die "Could not write to $oinkmaster_provider_includes_file. $!\n";
 990
 991         # Loop through the file content.
 992         foreach my $line (@lines) {
 993                 # Remove newlines.
 994                 chomp($line);
 995
 996                 # Skip line if we found our given provider and the action should be remove.
 997                 next if (($line =~ /$provider/) && ($action eq "remove"));
 998
 999                 # Write the read-in line back to the file.
1000                 print FILE "$line\n";
1001         }
1002
1003         # Check if the file exists and add the provider if requested.
1004         if ((-f $provider_modified_sids_file) && ($action eq "add")) {
1005                 print FILE "include $provider_modified_sids_file\n";
1006         }
1007
1008         # Close file handle.
1009         close(FILE);
1010 }
1011
1012 #
1013 ## Function to read-in the given enabled or disables sids file.
1014 #
1015 sub read_enabled_disabled_sids_file($) {
1016         my ($file) = @_;
1017
1018         # Temporary hash to store the sids and their state. It will be
1019         # returned at the end of this function.
1020         my %temphash;
1021
1022         # Open the given filename.
1023         open(FILE, "$file") or die "Could not open $file. $!\n";
1024
1025         # Loop through the file.
1026         while(<FILE>) {
1027                 # Remove newlines.
1028                 chomp $_;
1029
1030                 # Skip blank lines.
1031                 next if ($_ =~ /^\s*$/);
1032
1033                 # Skip coments.
1034                 next if ($_ =~ /^\#/);
1035
1036                 # Splitt line into sid and state part.
1037                 my ($state, $sid) = split(" ", $_);
1038
1039                 # Skip line if the sid is not numeric.
1040                 next unless ($sid =~ /\d+/ );
1041
1042                 # Check if the sid was enabled.
1043                 if ($state eq "enablesid") {
1044                         # Add the sid and its state as enabled to the temporary hash.
1045                         $temphash{$sid} = "enabled";
1046                 # Check if the sid was disabled.
1047                 } elsif ($state eq "disablesid") {
1048                         # Add the sid and its state as disabled to the temporary hash.
1049                         $temphash{$sid} = "disabled";
1050                 # Invalid state - skip the current sid and state.
1051                 } else {
1052                         next;
1053                 }
1054         }
1055
1056         # Close filehandle.
1057         close(FILE);
1058
1059         # Return the hash.
1060         return %temphash;
1061 }
1062
1063 #
1064 ## Function to check if the IDS is running.
1065 #
1066 sub ids_is_running () {
1067         if(-f $idspidfile) {
1068                 # Open PID file for reading.
1069                 open(PIDFILE, "$idspidfile") or die "Could not open $idspidfile. $!\n";
1070
1071                 # Grab the process-id.
1072                 my $pid = <PIDFILE>;
1073
1074                 # Close filehandle.
1075                 close(PIDFILE);
1076
1077                 # Remove any newline.
1078                 chomp($pid);
1079
1080                 # Check if a directory for the process-id exists in proc.
1081                 if(-d "/proc/$pid") {
1082                         # The IDS daemon is running return the process id.
1083                         return $pid;
1084                 }
1085         }
1086
1087         # Return nothing - IDS is not running.
1088         return;
1089 }
1090
1091 #
1092 ## Function to call suricatactrl binary with a given command.
1093 #
1094 sub call_suricatactrl ($) {
1095         # Get called option.
1096         my ($option, $interval) = @_;
1097
1098         # Loop through the array of supported commands and check if
1099         # the given one is part of it.
1100         foreach my $cmd (@suricatactrl_cmds) {
1101                 # Skip current command unless the given one has been found.
1102                 next unless($cmd eq $option);
1103
1104                 # Check if the given command is "cron".
1105                 if ($option eq "cron") {
1106                         # Check if an interval has been given.
1107                         if ($interval) {
1108                                 # Check if the given interval is valid.
1109                                 foreach my $element (@cron_intervals) {
1110                                         # Skip current element until the given one has been found.
1111                                         next unless($element eq $interval);
1112
1113                                         # Call the suricatactrl binary and pass the "cron" command
1114                                         # with the requrested interval.
1115                                         &General::system("$suricatactrl", "$option", "$interval");
1116
1117                                         # Return "1" - True.
1118                                         return 1;
1119                                 }
1120                         }
1121
1122                         # If we got here, the given interval is not supported or none has been given. - Return nothing.
1123                         return;
1124                 } else {
1125                         # Call the suricatactrl binary and pass the requrested
1126                         # option to it.
1127                         &General::system("$suricatactrl", "$option");
1128
1129                         # Return "1" - True.
1130                         return 1;
1131                 }
1132         }
1133
1134         # Command not found - return nothing.
1135         return;
1136 }
1137
1138 #
1139 ## Function to create a new empty file.
1140 #
1141 sub create_empty_file($) {
1142         my ($file) = @_;
1143
1144         # Check if the given file exists.
1145         if(-e $file) {
1146                 # Do nothing to prevent from overwriting existing files.
1147                 return;
1148         }
1149
1150         # Open the file for writing.
1151         open(FILE, ">$file") or die "Could not write to $file. $!\n";
1152
1153         # Close file handle.
1154         close(FILE);
1155
1156         # Return true.
1157         return 1;
1158 }
1159
1160 #
1161 ## Private function to check if the file permission of the rulespath are correct.
1162 ## If not, call suricatactrl to fix them.
1163 #
1164 sub _check_rulesdir_permissions() {
1165         # Check if the rulepath main directory is writable.
1166         unless (-W $rulespath) {
1167                 # If not call suricatctrl to fix it.
1168                 &call_suricatactrl("fix-rules-dir");
1169         }
1170
1171         # Open snort rules directory and do a directory listing.
1172         opendir(DIR, $rulespath) or die $!;
1173         # Loop through the direcory.
1174         while (my $file = readdir(DIR)) {
1175                 # We only want files.
1176                 next unless (-f "$rulespath/$file");
1177
1178                 # Check if the file is writable by the user.
1179                 if (-W "$rulespath/$file") {
1180                         # Everything is okay - go on to the next file.
1181                         next;
1182                 } else {
1183                         # There are wrong permissions, call suricatactrl to fix it.
1184                         &call_suricatactrl("fix-rules-dir");
1185                 }
1186         }
1187 }
1188
1189 #
1190 ## Private function to cleanup the directory which contains
1191 ## the IDS rules, before extracting and modifing the new ruleset.
1192 #
1193 sub _cleanup_rulesdir() {
1194         # Open rules directory and do a directory listing.
1195         opendir(DIR, $rulespath) or die $!;
1196
1197         # Loop through the direcory.
1198         while (my $file = readdir(DIR)) {
1199                 # We only want files.
1200                 next unless (-f "$rulespath/$file");
1201
1202                 # Skip rules file for whitelisted hosts.
1203                 next if ("$rulespath/$file" eq $whitelist_file);
1204
1205                 # Skip rules file with local rules.
1206                 next if ("$rulespath/$file" eq $local_rules_file);
1207
1208                 # Delete the current processed file, if not, exit this function
1209                 # and return an error message.
1210                 unlink("$rulespath/$file") or return "Could not delete $rulespath/$file. $!\n";
1211         }
1212
1213         # Return nothing;
1214         return;
1215 }
1216
1217 #
1218 ## Function to generate the file which contains the home net information.
1219 #
1220 sub generate_home_net_file() {
1221         my %netsettings;
1222
1223         # Read-in network settings.
1224         &General::readhash("${General::swroot}/ethernet/settings", \%netsettings);
1225
1226         # Get available network zones.
1227         my @network_zones = &Network::get_available_network_zones();
1228
1229         # Temporary array to store network address and prefix of the configured
1230         # networks.
1231         my @networks;
1232
1233         # Loop through the array of available network zones.
1234         foreach my $zone (@network_zones) {
1235                 # Check if the current processed zone is red.
1236                 if($zone eq "red") {
1237                         # Grab the IP-address of the red interface.
1238                         my $red_address = &get_red_address();
1239
1240                         # Check if an address has been obtained.
1241                         if ($red_address) {
1242                                 # Generate full network string.
1243                                 my $red_network = join("/", $red_address, "32");
1244
1245                                 # Add the red network to the array of networks.
1246                                 push(@networks, $red_network);
1247                         }
1248
1249                         # Check if the configured RED_TYPE is static.
1250                         if ($netsettings{'RED_TYPE'} eq "STATIC") {
1251                                 # Get configured and enabled aliases.
1252                                 my @aliases = &get_aliases();
1253
1254                                 # Loop through the array.
1255                                 foreach my $alias (@aliases) {
1256                                         # Add "/32" prefix.
1257                                         my $network = join("/", $alias, "32");
1258
1259                                         # Add the generated network to the array of networks.
1260                                         push(@networks, $network);
1261                                 }
1262                         }
1263                 # Process remaining network zones.
1264                 } else {
1265                         # Convert current zone name into upper case.
1266                         $zone = uc($zone);
1267
1268                         # Generate key to access the required data from the netsettings hash.
1269                         my $zone_netaddress = $zone . "_NETADDRESS";
1270                         my $zone_netmask = $zone . "_NETMASK";
1271
1272                         # Obtain the settings from the netsettings hash.
1273                         my $netaddress = $netsettings{$zone_netaddress};
1274                         my $netmask = $netsettings{$zone_netmask};
1275
1276                         # Convert the subnetmask into prefix notation.
1277                         my $prefix = &Network::convert_netmask2prefix($netmask);
1278
1279                         # Generate full network string.
1280                         my $network = join("/", $netaddress,$prefix);
1281
1282                         # Check if the network is valid.
1283                         if(&Network::check_subnet($network)) {
1284                                 # Add the generated network to the array of networks.
1285                                 push(@networks, $network);
1286                         }
1287                 }
1288         }
1289
1290         # Format home net declaration.
1291         my $line = "\"[" . join(',', @networks) . "]\"";
1292
1293         # Open file to store the addresses of the home net.
1294         open(FILE, ">$homenet_file") or die "Could not open $homenet_file. $!\n";
1295
1296         # Print yaml header.
1297         print FILE "%YAML 1.1\n";
1298         print FILE "---\n\n";
1299
1300         # Print notice about autogenerated file.
1301         print FILE "#Autogenerated file. Any custom changes will be overwritten!\n";
1302
1303         # Print the generated and required HOME_NET declaration to the file.
1304         print FILE "HOME_NET:\t$line\n";
1305
1306         # Close file handle.
1307         close(FILE);
1308 }
1309
1310 #
1311 # Function to generate and write the file which contains the configured and used DNS servers.
1312 #
1313 sub generate_dns_servers_file() {
1314         # Get the used DNS servers.
1315         my @nameservers = &General::get_nameservers();
1316
1317         # Get network settings.
1318         my %netsettings;
1319         &General::readhash("${General::swroot}/ethernet/settings", \%netsettings);
1320
1321         # Format dns servers declaration.
1322         my $line = "";
1323
1324         # Check if the system has configured nameservers.
1325         if (@nameservers) {
1326                 # Add the GREEN address as DNS servers.
1327                 push(@nameservers, $netsettings{'GREEN_ADDRESS'});
1328
1329                 # Check if a BLUE zone exists.
1330                 if ($netsettings{'BLUE_ADDRESS'}) {
1331                         # Add the BLUE address to the array of nameservers.
1332                         push(@nameservers, $netsettings{'BLUE_ADDRESS'});
1333                 }
1334
1335                 # Generate the line which will be written to the DNS servers file.
1336                 $line = join(",", @nameservers);
1337         } else {
1338                 # External net simply contains (any).
1339                 $line = "\$EXTERNAL_NET";
1340         }
1341
1342         # Open file to store the used DNS server addresses.
1343         open(FILE, ">$dns_servers_file") or die "Could not open $dns_servers_file. $!\n";
1344
1345         # Print yaml header.
1346         print FILE "%YAML 1.1\n";
1347         print FILE "---\n\n";
1348
1349         # Print notice about autogenerated file.
1350         print FILE "#Autogenerated file. Any custom changes will be overwritten!\n";
1351
1352         # Print the generated DNS declaration to the file.
1353         print FILE "DNS_SERVERS:\t\"[$line]\"\n";
1354
1355         # Close file handle.
1356         close(FILE);
1357 }
1358
1359 #
1360 # Function to generate and write the file which contains the HTTP_PORTS definition.
1361 #
1362 sub generate_http_ports_file() {
1363         my %proxysettings;
1364
1365         # Read-in proxy settings
1366         &General::readhash("${General::swroot}/proxy/advanced/settings", \%proxysettings);
1367
1368         # Check if the proxy is enabled.
1369         if (( -e "${General::swroot}/proxy/enable") || (-e "${General::swroot}/proxy/enable_blue")) {
1370                 # Add the proxy port to the array of HTTP ports.
1371                 push(@http_ports, $proxysettings{'PROXY_PORT'});
1372         }
1373
1374         # Check if the transparent mode of the proxy is enabled.
1375         if ((-e "${General::swroot}/proxy/transparent") || (-e "${General::swroot}/proxy/transparent_blue")) {
1376                 # Add the transparent proxy port to the array of HTTP ports.
1377                 push(@http_ports, $proxysettings{'TRANSPARENT_PORT'});
1378         }
1379
1380         # Format HTTP_PORTS declaration.
1381         my $line = "";
1382
1383         # Generate line which will be written to the http ports file.
1384         $line = join(",", @http_ports);
1385
1386         # Open file to store the HTTP_PORTS.
1387         open(FILE, ">$http_ports_file") or die "Could not open $http_ports_file. $!\n";
1388
1389         # Print yaml header.
1390         print FILE "%YAML 1.1\n";
1391         print FILE "---\n\n";
1392
1393         # Print notice about autogenerated file.
1394         print FILE "#Autogenerated file. Any custom changes will be overwritten!\n";
1395
1396         # Print the generated HTTP_PORTS declaration to the file.
1397         print FILE "HTTP_PORTS:\t\"[$line]\"\n";
1398
1399         # Close file handle.
1400         close(FILE);
1401 }
1402
1403 #
1404 ## Function to generate and write the file for used rulefiles file for a given provider.
1405 ##
1406 ## The function requires as first argument a provider handle, and as second an array with files.
1407 #
1408 sub write_used_provider_rulefiles_file($@) {
1409         my ($provider, @files) = @_;
1410
1411         # Get the path and file for the provider specific used rulefiles file.
1412         my $used_provider_rulesfile_file = &get_used_provider_rulesfile_file($provider);
1413
1414         # Open file for used rulefiles.
1415         open (FILE, ">", "$used_provider_rulesfile_file") or die "Could not write to $used_provider_rulesfile_file. $!\n";
1416
1417         # Write yaml header to the file.
1418         print FILE "%YAML 1.1\n";
1419         print FILE "---\n\n";
1420
1421         # Write header to file.
1422         print FILE "#Autogenerated file. Any custom changes will be overwritten!\n";
1423
1424         # Loop through the array of given files.
1425         foreach my $file (@files) {
1426                 # Check if the given filename exists and write it to the file of used rulefiles.
1427                 if(-f "$rulespath/$file") {
1428                         print FILE " - $file\n";
1429                 }
1430         }
1431
1432         # Close file after writing.
1433         close(FILE);
1434 }
1435
1436 #
1437 ## Function to write the main file for provider rulesfiles inclusions.
1438 ##
1439 ## This function requires an array of provider handles.
1440 #
1441 sub write_main_used_rulefiles_file (@) {
1442         my (@providers) = @_;
1443
1444         # Call function to write the static rulefiles file.
1445         &_write_default_rulefiles_file();
1446
1447         # Open file for used rulefils inclusion.
1448         open (FILE, ">", "$suricata_used_providers_file") or die "Could not write to $suricata_used_providers_file. $!\n";
1449
1450         # Write yaml header to the file.
1451         print FILE "%YAML 1.1\n";
1452         print FILE "---\n\n";
1453
1454         # Write header to file.
1455         print FILE "#Autogenerated file. Any custom changes will be overwritten!\n";
1456
1457         # Loop through the list of given providers.
1458         foreach my $provider (@providers) {
1459                 # Call function to get the providers used rulefiles file.
1460                 my $filename = &get_used_provider_rulesfile_file($provider);
1461
1462                 # Check if the file exists and write it into the used rulefiles file.
1463                 if (-f $filename) {
1464                         # Print the provider to the file.
1465                         print FILE "include\: $filename\n";
1466                 }
1467         }
1468
1469         # Close the filehandle after writing.
1470         close(FILE);
1471 }
1472
1473 sub _write_default_rulefiles_file () {
1474         # Get enabled application layer protocols.
1475         my @enabled_app_layer_protos = &get_suricata_enabled_app_layer_protos();
1476
1477         # Open file.
1478         open (FILE, ">", $suricata_default_rulefiles_file) or die "Could not write to $suricata_default_rulefiles_file. $!\n";
1479
1480         # Write yaml header to the file.
1481         print FILE "%YAML 1.1\n";
1482         print FILE "---\n\n";
1483
1484         # Write notice about autogenerated file.
1485         print FILE "#Autogenerated file. Any custom changes will be overwritten!\n";
1486
1487         # Loop through the array of static included rulesfiles.
1488         foreach my $file (@static_included_rulefiles) {
1489                 # Check if the file exists.
1490                 if (-f "$rulespath/$file") {
1491                         # Write the rulesfile name to the file.
1492                         print FILE " - $rulespath/$file\n";
1493                 }
1494         }
1495
1496         print FILE "\n#Default rules for used application layer protocols.\n";
1497         foreach my $enabled_app_layer_proto (@enabled_app_layer_protos) {
1498                 # Check if the current processed app layer proto needs to be translated
1499                 # into an application name.
1500                 if (exists($tr_app_layer_proto{$enabled_app_layer_proto})) {
1501                         # Obtain the translated application name for this protocol.
1502                         $enabled_app_layer_proto = $tr_app_layer_proto{$enabled_app_layer_proto};
1503                 }
1504
1505                 # Generate filename.
1506                 my $rulesfile = "$default_rulespath/$enabled_app_layer_proto\.rules";
1507
1508                 # Check if such a file exists.
1509                 if (-f "$rulesfile") {
1510                         # Write the rulesfile name to the file.
1511                         print FILE " - $rulesfile\n";
1512                 }
1513
1514                 # Generate filename with "events" in filename.
1515                 $rulesfile = "$default_rulespath/$enabled_app_layer_proto\-events.rules";
1516
1517                 # Check if this file exists.
1518                 if (-f "$rulesfile" ) {
1519                         # Write the rulesfile name to the file.
1520                         print FILE " - $rulesfile\n";
1521                 }
1522         }
1523
1524         # Close the file handle
1525         close(FILE);
1526 }
1527
1528 #
1529 ## Tiny function to generate the full path and name for the used_provider_rulesfile file of a given provider.
1530 #
1531 sub get_used_provider_rulesfile_file ($) {
1532         my ($provider) = @_;
1533
1534         my $filename = "$settingsdir/suricata\-$provider\-used\-rulefiles.yaml";
1535
1536         # Return the gernerated file.
1537         return $filename;
1538 }
1539
1540 #
1541 ## Function to generate and write the file for modify the ruleset.
1542 #
1543 sub write_modify_sids_file() {
1544         # Get configured settings.
1545         my %idssettings=();
1546         &General::readhash("$ids_settings_file", \%idssettings);
1547
1548         # Open modify sid's file for writing.
1549         open(FILE, ">$modify_sids_file") or die "Could not write to $modify_sids_file. $!\n";
1550
1551         # Write file header.
1552         print FILE "#Autogenerated file. Any custom changes will be overwritten!\n";
1553
1554         # Check if the traffic only should be monitored.
1555         unless($idssettings{'MONITOR_TRAFFIC_ONLY'} eq 'on') {
1556                 # Suricata is in IPS mode, which means that the rule actions have to be changed
1557                 # from 'alert' to 'drop', however not all rules should be changed.  Some rules
1558                 # exist purely to set a flowbit which is used to convey other information, such
1559                 # as a specific type of file being downloaded, to other rulewhich then check for
1560                 # malware in that file.  Rules which fall into the first category should stay as
1561                 # alert since not all flows of that type contain malware.
1562
1563                 # These types of rulesfiles contain meta-data which gives the action that should
1564                 # be used when in IPS mode.  Do the following:
1565                 #
1566                 # 1. Disable all rules and set the action to 'drop'
1567                 # 2. Set the action back to 'alert' if the rule contains 'flowbits:noalert;'
1568                 #    This should give rules not in the policy a reasonable default if the user
1569                 #    manually enables them.
1570                 # 3. Enable rules and set actions according to the meta-data strings.
1571
1572                 my $policy = 'balanced';  # Placeholder to allow policy to be changed.
1573
1574                         print FILE <<END;
1575 modifysid * "^#(?:alert|drop)(.+policy $policy-ips alert)" | "alert\${1}"
1576 modifysid * "^#(?:alert|drop)(.+policy $policy-ips drop)" | "drop\${1}"
1577 modifysid * "^(#?)(?:alert|drop)" | "\${1}drop"
1578 modifysid * "^(#?)drop(.+flowbits:noalert;)" | "\${1}alert\${2}"
1579 END
1580                 }
1581
1582         # Close file handle.
1583         close(FILE);
1584 }
1585
1586 #
1587 ## Function to get the ruleset date for a given provider.
1588 ##
1589 ## The function simply return the creation date in a human read-able format
1590 ## of the stored providers rulesfile.
1591 #
1592 sub get_ruleset_date($) {
1593         my ($provider) = @_;
1594         my $date;
1595         my $mtime;
1596
1597         # Load neccessary perl modules for file stat and to format the timestamp.
1598         use File::stat;
1599         use POSIX qw( strftime );
1600
1601         # Get the stored rulesfile for this provider.
1602         my $stored_rulesfile = &_get_dl_rulesfile($provider);
1603
1604         # Check if we got a file.
1605         if (-f $stored_rulesfile) {
1606                 # Call stat on the rulestarball.
1607                 my $stat = stat("$stored_rulesfile");
1608
1609                 # Get timestamp the file creation.
1610                 $mtime = $stat->mtime;
1611         }
1612
1613         # Check if the timestamp has not been grabbed.
1614         unless ($mtime) {
1615                 # Return N/A for Not available.
1616                 return "N/A";
1617         }
1618
1619         # Convert into human read-able format.
1620         $date = strftime('%Y-%m-%d %H:%M:%S', localtime($mtime));
1621
1622         # Return the date.
1623         return $date;
1624 }
1625
1626 #
1627 ## Function to gather the version of suricata.
1628 #
1629 sub get_suricata_version($) {
1630         my ($format) = @_;
1631
1632         # Execute piped suricata command and return the version information.
1633         open(SURICATA, "suricata -V |") or die "Couldn't execute program: $!";
1634
1635         # Grab and store the output of the piped program.
1636         my $version_string = <SURICATA>;
1637
1638         # Close pipe.
1639         close(SURICATA);
1640
1641         # Remove newlines.
1642         chomp($version_string);
1643
1644         # Grab the version from the version string.
1645         $version_string =~ /([0-9]+([.][0-9]+)+)/;
1646
1647         # Splitt the version into single chunks.
1648         my ($major_ver, $minor_ver, $patchlevel) = split(/\./, $1);
1649
1650         # Check and return the requested version sheme.
1651         if ($format eq "major") {
1652                 # Return the full version.
1653                 return "$major_ver";
1654         } elsif ($format eq "minor") {
1655                 # Return the major and minor part.
1656                 return "$major_ver.$minor_ver";
1657         } else {
1658                 # Return the full version string.
1659                 return "$major_ver.$minor_ver.$patchlevel";
1660         }
1661 }
1662
1663 #
1664 ## Function to get the enabled application layer protocols.
1665 #
1666 sub get_suricata_enabled_app_layer_protos() {
1667         # Array to store and return the enabled app layer protos.
1668         my @enabled_app_layer_protos = ();
1669
1670         # Execute piped suricata command and return the list of
1671         # enabled application layer protocols.
1672         open(SURICATA, "suricata --list-app-layer-protos |") or die "Could not execute program: $!";
1673
1674         # Grab and store the list of enabled application layer protocols.
1675         my @output = <SURICATA>;
1676
1677         # Close pipe.
1678         close(SURICATA);
1679
1680         # Merge allways enabled static application layers protocols array.
1681         @enabled_app_layer_protos = @static_enabled_app_layer_protos;
1682
1683         # Loop through the array which contains the output of suricata.
1684         foreach my $line (@output) {
1685                 # Skip header line which starts with "===".
1686                 next if ($line =~ /^\s*=/);
1687
1688                 # Skip info or warning lines.
1689                 next if ($line =~ /\s*--/);
1690
1691                 # Remove newlines.
1692                 chomp($line);
1693
1694                 # Add enabled app layer proto to the array.
1695                 push(@enabled_app_layer_protos, $line);
1696         }
1697
1698         # Sort the array.
1699         @enabled_app_layer_protos = sort(@enabled_app_layer_protos);
1700
1701         # Return the array.
1702         return @enabled_app_layer_protos;
1703 }
1704
1705 #
1706 ## Function to generate the rules file with whitelisted addresses.
1707 #
1708 sub generate_ignore_file() {
1709         my %ignored = ();
1710
1711         # SID range 1000000-1999999 Reserved for Local Use
1712         # Put your custom rules in this range to avoid conflicts
1713         my $sid = 1500000;
1714
1715         # Read-in ignoredfile.
1716         &General::readhasharray($IDS::ignored_file, \%ignored);
1717
1718         # Open ignorefile for writing.
1719         open(FILE, ">$IDS::whitelist_file") or die "Could not write to $IDS::whitelist_file. $!\n";
1720
1721         # Config file header.
1722         print FILE "# Autogenerated file.\n";
1723         print FILE "# All user modifications will be overwritten.\n\n";
1724
1725         # Add all user defined addresses to the whitelist.
1726         #
1727         # Check if the hash contains any elements.
1728         if (keys (%ignored)) {
1729                 # Loop through the entire hash and write the host/network
1730                 # and remark to the ignore file.
1731                 while ( (my $key) = each %ignored) {
1732                         my $address = $ignored{$key}[0];
1733                         my $remark = $ignored{$key}[1];
1734                         my $status = $ignored{$key}[2];
1735
1736                         # Check if the status of the entry is "enabled".
1737                         if ($status eq "enabled") {
1738                                 # Check if the address/network is valid.
1739                                 if ((&General::validip($address)) || (&General::validipandmask($address))) {
1740                                         # Write rule line to the file to pass any traffic from this IP
1741                                         print FILE "pass ip $address any -> any any (msg:\"pass all traffic from/to $address\"\; bypass; sid:$sid\;)\n";
1742
1743                                         # Increment sid.
1744                                         $sid++;
1745                                 }
1746                         }
1747                 }
1748         }
1749
1750         close(FILE);
1751 }
1752
1753 #
1754 ## Function to set correct ownership for single files and directories.
1755 #
1756
1757 sub set_ownership($) {
1758         my ($target) = @_;
1759
1760         # User and group of the WUI.
1761         my $uname = "nobody";
1762         my $grname = "nobody";
1763
1764         # The chown function implemented in perl requies the user and group as nummeric id's.
1765         my $uid = getpwnam($uname);
1766         my $gid = getgrnam($grname);
1767
1768         # Check if the given target exists.
1769         unless ($target) {
1770                 # Stop the script and print error message.
1771                 die "The $target does not exist. Cannot change the ownership!\n";
1772         }
1773
1774         # Check weather the target is a file or directory.
1775         if (-f $target) {
1776                 # Change ownership ot the single file.
1777                 chown($uid, $gid, "$target");
1778         } elsif (-d $target) {
1779                 # Do a directory listing.
1780                 opendir(DIR, $target) or die $!;
1781                         # Loop through the direcory.
1782                         while (my $file = readdir(DIR)) {
1783
1784                                 # We only want files.
1785                                 next unless (-f "$target/$file");
1786
1787                                 # Set correct ownership for the files.
1788                                 chown($uid, $gid, "$target/$file");
1789                         }
1790
1791                 closedir(DIR);
1792
1793                 # Change ownership of the directory.
1794                 chown($uid, $gid, "$target");
1795         }
1796 }
1797
1798 #
1799 ## Function to read-in the aliases file and returns all configured and enabled aliases.
1800 #
1801 sub get_aliases() {
1802         # Location of the aliases file.
1803         my $aliases_file = "${General::swroot}/ethernet/aliases";
1804
1805         # Array to store the aliases.
1806         my @aliases;
1807
1808         # Check if the file is empty.
1809         if (-z $aliases_file) {
1810                 # Abort nothing to do.
1811                 return;
1812         }
1813
1814         # Open the aliases file.
1815         open(ALIASES, $aliases_file) or die "Could not open $aliases_file. $!\n";
1816
1817         # Loop through the file content.
1818         while (my $line = <ALIASES>) {
1819                 # Remove newlines.
1820                 chomp($line);
1821
1822                 # Splitt line content into single chunks.
1823                 my ($address, $state, $remark) = split(/\,/, $line);
1824
1825                 # Check if the state of the current processed alias is "on".
1826                 if ($state eq "on") {
1827                         # Check if the address is valid.
1828                         if(&Network::check_ip_address($address)) {
1829                                 # Add the alias to the array of aliases.
1830                                 push(@aliases, $address);
1831                         }
1832                 }
1833         }
1834
1835         # Close file handle.
1836         close(ALIASES);
1837
1838         # Return the array.
1839         return @aliases;
1840 }
1841
1842 #
1843 ## Function to grab the current assigned IP-address on red.
1844 #
1845 sub get_red_address() {
1846         # File, which contains the current IP-address of the red interface.
1847         my $file = "${General::swroot}/red/local-ipaddress";
1848
1849         # Check if the file exists.
1850         if (-e $file) {
1851                 # Open the given file.
1852                 open(FILE, "$file") or die "Could not open $file.";
1853
1854                 # Obtain the address from the first line of the file.
1855                 my $address = <FILE>;
1856
1857                 # Close filehandle
1858                 close(FILE);
1859
1860                 # Remove newlines.
1861                 chomp $address;
1862
1863                 # Check if the grabbed address is valid.
1864                 if (&General::validip($address)) {
1865                         # Return the address.
1866                         return $address;
1867                 }
1868         }
1869
1870         # Return nothing.
1871         return;
1872 }
1873
1874 #
1875 ## Function to get the used rules files of a given provider.
1876 #
1877 sub read_used_provider_rulesfiles($) {
1878         my ($provider) = @_;
1879
1880         # Array to store the used rulefiles.
1881         my @used_rulesfiles = ();
1882
1883         # Get the used rulesefile file for the provider.
1884         my $rulesfile_file = &get_used_provider_rulesfile_file($provider);
1885
1886         # Check if the a used rulesfile exists for this provider.
1887         if (-f $rulesfile_file) {
1888                 # Open the file or used rulefiles and read-in content.
1889                 open(FILE, $rulesfile_file) or die "Could not open $rulesfile_file. $!\n";
1890
1891                 while (<FILE>) {
1892                         # Assign the current line to a nice variable.
1893                         my $line = $_;
1894
1895                         # Remove newlines.
1896                         chomp($line);
1897
1898                         # Skip comments.
1899                         next if ($line =~ /\#/);
1900
1901                         # Skip blank  lines.
1902                         next if ($line =~ /^\s*$/);
1903
1904                         # Gather the rulefile.
1905                         if ($line =~ /.*- (.*)/) {
1906                                 my $rulefile = $1;
1907
1908                                 # Add the rulefile to the array of used rulesfiles.
1909                                 push(@used_rulesfiles, $rulefile);
1910                         }
1911                 }
1912
1913                 # Close the file.
1914                 close(FILE);
1915         }
1916
1917         # Return the array of used rulesfiles.
1918         return @used_rulesfiles;
1919 }
1920
1921 #
1922 ## Function to write the lock file for locking the WUI, while
1923 ## the autoupdate script runs.
1924 #
1925 sub lock_ids_page() {
1926         # Call subfunction to create the file.
1927         &create_empty_file($ids_page_lock_file);
1928 }
1929
1930 #
1931 ## Function to release the lock of the WUI, again.
1932 #
1933 sub unlock_ids_page() {
1934         # Delete lock file.
1935         unlink($ids_page_lock_file);
1936 }
1937
1938 1;