plugins/filters/filters.php

   1 <?php
   2
   3 /**
   4  * Message and Spam Filter Plugin - Filtering Functions
   5  *
   6  * @copyright 1999-2020 The SquirrelMail Project Team
   7  * @license http://opensource.org/licenses/gpl-license.php GNU Public License
   8  * @version $Id$
   9  * @package plugins
  10  * @subpackage filters
  11  */
  12
  13 // TODO: This plugin has an issue that seems to corrupt folder cache for subfolders of INBOX
  14 /**
  15  * do not allow to call this file directly
  16  */
  17 if (isset($_SERVER['SCRIPT_FILENAME']) && $_SERVER['SCRIPT_FILENAME'] == __FILE__) {
  18     header("Location: ../../src/login.php");
  19     die();
  20 }
  21
  22 /** load globals */
  23 global $UseSeparateImapConnection,
  24     $AllowSpamFilters, $SpamFilters_YourHop, $SpamFilters_ShowCommercial,
  25     $SpamFilters_DNScache, $SpamFilters_BulkQuery, $SpamFilters_SharedCache,
  26     $SpamFilters_CacheTTL;
  27
  28 /**
  29  * load required functions. Plugin depends on IMAP functions and they are not
  30  * loaded in src/webmail.php
  31  */
  32 include_once (SM_PATH . 'functions/imap.php');
  33
  34 /** load default config */
  35 if (file_exists(SM_PATH . 'plugins/filters/config_default.php')) {
  36     include_once (SM_PATH . 'plugins/filters/config_default.php');
  37 } else {
  38     // default config was removed.
  39     $UseSeparateImapConnection = false;
  40     $AllowSpamFilters = true;
  41     $SpamFilters_YourHop = ' ';
  42     $SpamFilters_ShowCommercial = false;
  43     $SpamFilters_DNScache = array();
  44     $SpamFilters_BulkQuery = '';
  45     $SpamFilters_SharedCache = true;
  46     $SpamFilters_CacheTTL = 7200;
  47 }
  48
  49 if (file_exists(SM_PATH . 'config/filters_config.php')) {
  50     include_once (SM_PATH . 'config/filters_config.php');
  51 } elseif (file_exists(SM_PATH . 'plugins/filters/config.php')) {
  52     include_once (SM_PATH . 'plugins/filters/config.php');
  53 }
  54
  55 /**
  56  * Register option blocks
  57  * @access private
  58  */
  59 function filters_optpage_register_block() {
  60     global $optpage_blocks, $AllowSpamFilters;
  61
  62     $optpage_blocks[] = array(
  63         'name' => _("Message Filters"),
  64         'url'  => SM_PATH . 'plugins/filters/options.php',
  65         'desc' => _("Filtering enables messages with different criteria to be automatically filtered into different folders for easier organization."),
  66         'js'   => false
  67     );
  68
  69     if ($AllowSpamFilters) {
  70         $optpage_blocks[] = array(
  71             'name' => _("SPAM Filters"),
  72             'url'  => SM_PATH . 'plugins/filters/spamoptions.php',
  73             'desc' => _("SPAM filters allow you to select from various DNS based blacklists to detect junk email in your INBOX and move it to another folder (like Trash)."),
  74             'js'   => false
  75         );
  76     }
  77 }
  78
  79 /* Receive the status of the folder and do something with it */
  80 function filters_folder_status($statusarr) {
  81
  82     global $filter_inbox_count;
  83     if (empty($filter_inbox_count)) $filter_inbox_count=0;
  84
  85     if ($statusarr['MAILBOX'] == 'INBOX')
  86     {
  87      if (!empty($statusarr['MESSAGES'])) $filter_inbox_count=$statusarr['MESSAGES'];
  88     }
  89 }
  90
  91 /**
  92  * Saves the DNS Cache to disk
  93  * @access private
  94  */
  95 function filters_SaveCache () {
  96     global $data_dir, $SpamFilters_DNScache;
  97
  98     if (file_exists($data_dir . '/dnscache')) {
  99         $fp = fopen($data_dir . '/dnscache', 'r');
 100     } else {
 101         $fp = false;
 102     }
 103     if ($fp) {
 104         flock($fp,LOCK_EX);
 105     } else {
 106        $fp = fopen($data_dir . '/dnscache', 'w+');
 107        fclose($fp);
 108        $fp = fopen($data_dir . '/dnscache', 'r');
 109        flock($fp,LOCK_EX);
 110     }
 111     $fp1 = fopen($data_dir . '/dnscache', 'w+');
 112
 113     foreach ($SpamFilters_DNScache as $Key=> $Value) {
 114        $tstr = $Key . ',' . $Value['L'] . ',' . $Value['T'] . "\n";
 115        fputs ($fp1, $tstr);
 116     }
 117     fclose($fp1);
 118     flock($fp,LOCK_UN);
 119     fclose($fp);
 120 }
 121
 122 /**
 123  * Loads the DNS Cache from disk
 124  * @access private
 125  */
 126 function filters_LoadCache () {
 127     global $data_dir, $SpamFilters_DNScache;
 128
 129     if (file_exists($data_dir . '/dnscache')) {
 130         $SpamFilters_DNScache = array();
 131         if ($fp = fopen ($data_dir . '/dnscache', 'r')) {
 132             flock($fp,LOCK_SH);
 133             while ($data = fgetcsv($fp,1024)) {
 134                if ($data[2] > time()) {
 135                   $SpamFilters_DNScache[$data[0]]['L'] = $data[1];
 136                   $SpamFilters_DNScache[$data[0]]['T'] = $data[2];
 137                }
 138             }
 139             flock($fp,LOCK_UN);
 140         }
 141     }
 142 }
 143
 144 /**
 145  * Uses the BulkQuery executable to query all the RBLs at once
 146  * @param array $filters Array of SPAM Filters
 147  * @param array $IPs Array of IP Addresses
 148  * @access private
 149  */
 150 function filters_bulkquery($filters, $IPs) {
 151     global $attachment_dir, $username,
 152            $SpamFilters_DNScache, $SpamFilters_BulkQuery,
 153            $SpamFilters_CacheTTL;
 154
 155     if (count($IPs) > 0) {
 156         $rbls = array();
 157         foreach ($filters as $key => $value) {
 158             if ($filters[$key]['enabled']) {
 159                 if ($filters[$key]['dns']) {
 160                     $rbls[$filters[$key]['dns']] = true;
 161                 }
 162             }
 163         }
 164
 165         $bqfil = $attachment_dir . $username . '-bq.in';
 166         $fp = fopen($bqfil, 'w');
 167         fputs ($fp, $SpamFilters_CacheTTL . "\n");
 168         foreach ($rbls as $key => $value) {
 169             fputs ($fp, '.' . $key . "\n");
 170         }
 171         fputs ($fp, "----------\n");
 172         foreach ($IPs as $key => $value) {
 173             fputs ($fp, $key . "\n");
 174         }
 175         fclose ($fp);
 176         $bqout = array();
 177         exec ($SpamFilters_BulkQuery . ' < ' . $bqfil, $bqout);
 178         foreach ($bqout as $value) {
 179             $Chunks = explode(',', $value);
 180             $SpamFilters_DNScache[$Chunks[0]]['L'] = $Chunks[1];
 181             $SpamFilters_DNScache[$Chunks[0]]['T'] = $Chunks[2] + time();
 182         }
 183         unlink($bqfil);
 184     }
 185 }
 186
 187 /**
 188  * Starts the filtering process
 189  * @param array $hook_args (since 1.5.2) do hook arguments. Is used to check
 190  * hook name, array key = 0.
 191  * @access private
 192  */
 193 function start_filters($hook_args) {
 194     global $imapServerAddress, $imapPort, $imap_stream_options, $imap_stream,
 195            $imapConnection, $UseSeparateImapConnection, $AllowSpamFilters,
 196            $filter_inbox_count, $username;
 197
 198     // if there were filtering errors previously during
 199     // this login session, we won't try again
 200     //
 201     // (errors that this plugin was able to catch or a "NO"
 202     // response/failure from IMAP found in the current session,
 203     // which could have resulted from an attempted filter copy
 204     // (over quota), in which case execution halts before this
 205     // plugin can catch the problem -- note, however, that any
 206     // other IMAP "NO" failure (caused by unrelated actions) at
 207     // any time during the current session will cause this plugin
 208     // to effectively shut down)
 209     //
 210     sqgetGlobalVar('filters_error', $filters_error, SQ_SESSION, FALSE);
 211     sqgetGlobalVar('IMAP_FATAL_ERROR_TYPE', $imap_fatal_error, SQ_SESSION, '');
 212     if ($filters_error || $imap_fatal_error == 'NO')
 213         return;
 214
 215     /**
 216      * check hook that calls filtering. If filters are called by right_main_after_header,
 217      * do filtering only when we are in INBOX folder.
 218      */
 219     if ($hook_args[0]=='right_main_after_header' &&
 220         (sqgetGlobalVar('mailbox',$mailbox,SQ_FORM) && $mailbox!='INBOX')) {
 221         return;
 222     }
 223
 224     $filters = load_filters();
 225
 226     // No point running spam filters if there aren't any to run //
 227     if ($AllowSpamFilters) {
 228         $spamfilters = load_spam_filters();
 229
 230         $AllowSpamFilters = false;
 231         foreach($spamfilters as $value) {
 232             if ($value['enabled'] == SMPREF_ON) {
 233                 $AllowSpamFilters = true;
 234                 break;
 235             }
 236         }
 237     }
 238
 239     // No user filters, and no spam filters, no need to continue //
 240     if (!$AllowSpamFilters && empty($filters)) {
 241         return;
 242     }
 243
 244
 245     // Detect if we have already connected to IMAP or not.
 246     // Also check if we are forced to use a separate IMAP connection
 247     if ((!isset($imap_stream) && !isset($imapConnection)) ||
 248         $UseSeparateImapConnection ) {
 249             $stream = sqimap_login($username, false, $imapServerAddress,
 250                                 $imapPort, 10, $imap_stream_options);
 251             $previously_connected = false;
 252     } else if (isset($imapConnection)) {
 253         $stream = $imapConnection;
 254         $previously_connected = true;
 255     } else {
 256         $previously_connected = true;
 257         $stream = $imap_stream;
 258     }
 259
 260     if (!isset($filter_inbox_count)) {
 261         $aStatus = sqimap_status_messages ($stream, 'INBOX', array('MESSAGES'));
 262         if (!empty($aStatus['MESSAGES'])) {
 263             $filter_inbox_count=$aStatus['MESSAGES'];
 264         } else {
 265             $filter_inbox_count=0;
 266         }
 267     }
 268
 269     if ($filter_inbox_count > 0) {
 270         sqimap_mailbox_select($stream, 'INBOX');
 271         // Filter spam from inbox before we sort them into folders
 272         if ($AllowSpamFilters) {
 273             spam_filters($stream);
 274         }
 275
 276         // Sort into folders
 277         user_filters($stream);
 278     }
 279
 280     if (!$previously_connected) {
 281         sqimap_logout($stream);
 282     }
 283 }
 284
 285 /**
 286  * Does the loop through each filter
 287  * @param stream imap_stream the stream to read from
 288  * @access private
 289  */
 290 function user_filters($imap_stream) {
 291     global $data_dir, $username;
 292     $filters = load_filters();
 293     if (! $filters) return;
 294     $filters_user_scan = getPref($data_dir, $username, 'filters_user_scan');
 295
 296     $expunge = false;
 297     // For every rule
 298     for ($i=0, $num = count($filters); $i < $num; $i++) {
 299         // If it is the "combo" rule
 300         if ($filters[$i]['where'] == 'To or Cc') {
 301             /*
 302             *  If it's "TO OR CC", we have to do two searches, one for TO
 303             *  and the other for CC.
 304             */
 305             $expunge = filter_search_and_delete($imap_stream, 'TO',
 306                   $filters[$i]['what'], $filters[$i]['folder'], $filters_user_scan, $expunge);
 307             $expunge = filter_search_and_delete($imap_stream, 'CC',
 308                   $filters[$i]['what'], $filters[$i]['folder'], $filters_user_scan, $expunge);
 309         } else if ($filters[$i]['where'] == 'Header and Body') {
 310             $expunge = filter_search_and_delete($imap_stream, 'TEXT',
 311                   $filters[$i]['what'], $filters[$i]['folder'], $filters_user_scan, $expunge);
 312         } else if ($filters[$i]['where'] == 'Message Body') {
 313             $expunge = filter_search_and_delete($imap_stream, 'BODY',
 314                   $filters[$i]['what'], $filters[$i]['folder'], $filters_user_scan, $expunge);
 315         } else {
 316             /*
 317             *  If it's a normal TO, CC, SUBJECT, or FROM, then handle it
 318             *  normally.
 319             */
 320             $expunge = filter_search_and_delete($imap_stream, $filters[$i]['where'],
 321                  $filters[$i]['what'], $filters[$i]['folder'], $filters_user_scan, $expunge);
 322         }
 323     }
 324     // Clean out the mailbox whether or not auto_expunge is on
 325     // That way it looks like it was redirected properly
 326     if ($expunge) {
 327         sqimap_mailbox_expunge($imap_stream, 'INBOX');
 328     }
 329 }
 330
 331 /**
 332  * Creates and runs the IMAP command to filter messages
 333  * @param string $imap_stream TODO: Document this parameter
 334  * @param string $where Which part of the message to search (TO, CC, SUBJECT, etc...)
 335  * @param string $what String to search for
 336  * @param string $where_to Folder it will move to
 337  * @param string $user_scan Whether to search all or just unseen
 338  * @param string $should_expunge
 339  * @access private
 340  */
 341 function filter_search_and_delete($imap_stream, $where, $what, $where_to, $user_scan,
 342                                   $should_expunge) {
 343     global $languages, $squirrelmail_language, $allow_charset_search, $imap_server_type;
 344
 345     //TODO: make use of new mailbox cache. See mailbox_display.phpinfo
 346
 347     if (strtolower($where_to) == 'inbox') {
 348         return array();
 349     }
 350
 351     if ($user_scan == 'new') {
 352         $category = 'UNSEEN';
 353     } else {
 354         $category = 'ALL';
 355     }
 356     $category .= ' UNDELETED';
 357
 358     if ($allow_charset_search &&
 359         isset($languages[$squirrelmail_language]['CHARSET']) &&
 360         $languages[$squirrelmail_language]['CHARSET']) {
 361         $search_str = 'SEARCH CHARSET '
 362                     . strtoupper($languages[$squirrelmail_language]['CHARSET'])
 363                     . ' ' . $category;
 364     } else {
 365         $search_str = 'SEARCH CHARSET US-ASCII ' . $category;
 366     }
 367     if ($where == 'Header') {
 368         $what  = explode(':', $what);
 369         $where = strtoupper($where);
 370         $where = trim($where . ' ' . $what[0]);
 371         $what  = addslashes(trim($what[1]));
 372     }
 373
 374     // see comments in squirrelmail sqimap_search function
 375     if ($imap_server_type == 'macosx' || $imap_server_type == 'hmailserver') {
 376         $search_str .= ' ' . $where . ' ' . $what;
 377         /* read data back from IMAP */
 378         $read = sqimap_run_command($imap_stream, $search_str, true, $response, $message, TRUE);
 379     } else {
 380         $search_str .= ' ' . $where . ' {' . strlen($what) . "}";
 381         $sid = sqimap_session_id(true);
 382         fputs ($imap_stream, $sid . ' ' . $search_str . "\r\n");
 383         $read2 = sqimap_fgets($imap_stream);
 384         # server should respond with Ready for argument, then we will send search text
 385         #echo "RR2 $read2<br>";
 386         fputs ($imap_stream, "$what\r\n");
 387         #echo "SS $what<br>";
 388         $read2 = sqimap_fgets($imap_stream);
 389         #echo "RR2 $read2<br>";
 390         $read[]=$read2;
 391         $read3 = sqimap_fgets($imap_stream);
 392         #echo "RR3 $read3<br>";
 393         list($rtag,$response,$message)=explode(' ',$read3,3);
 394 ##        $read2 = sqimap_retrieve_imap_response($imap_stream, $sid, true,
 395 ##              $response, $message, $search_str, false, true, false);
 396         #echo "RR2 $read2 / RESPONSE $response<br>";
 397     }
 398
 399     if (isset($read[0])) {
 400         $ids = array();
 401         for ($i = 0, $iCnt = count($read); $i < $iCnt; ++$i) {
 402             if (preg_match("/^\* SEARCH (.+)$/", $read[$i], $regs)) {
 403                 $ids += explode(' ', trim($regs[1]));
 404             }
 405         }
 406         if ($response == 'OK' && count($ids)) {
 407             if (sqimap_mailbox_exists($imap_stream, $where_to)) {
 408                 if (!sqimap_msgs_list_move ($imap_stream, $ids, $where_to, false)) {
 409                     // if errors occurred, don't try to filter again during this session
 410                     sqsession_register(TRUE, 'filters_error');
 411                     global $color;
 412                     error_box(_("A problem occurred filtering messages. Check filter settings and account quota if applicable. Filtering is disabled for the remainder of this login session."), $color);
 413                 }
 414
 415                 // expunge even in the case of errors, in case some
 416                 // messages were filtered before the error happened
 417                 $should_expunge = true;
 418             }
 419         } elseif ($response != 'OK') {
 420             $query = $search_str . "\r\n".$what ."\r\n";
 421             if ($response == 'NO') {
 422                 if (strpos($message,'BADCHARSET') !== false ||
 423                     strpos($message,'character') !== false) {
 424                     sqm_trigger_imap_error('SQM_IMAP_BADCHARSET',$query, $response, $message);
 425                 } else {
 426                     sqm_trigger_imap_error('SQM_IMAP_ERROR',$query, $response, $message);
 427                 }
 428             } else {
 429                 sqm_trigger_imap_error('SQM_IMAP_ERROR',$query, $response, $message);
 430             }
 431         }
 432     }
 433     return $should_expunge;
 434 }
 435
 436 /**
 437  * Loops through all the Received Headers to find IP Addresses
 438  * @param stream imap_stream the stream to read from
 439  * @access private
 440  */
 441 function spam_filters($imap_stream) {
 442     global $data_dir, $username;
 443     global $SpamFilters_YourHop;
 444     global $SpamFilters_DNScache;
 445     global $SpamFilters_SharedCache;
 446     global $SpamFilters_BulkQuery;
 447     global $SpamFilters_CacheTTL;
 448
 449     $filters_spam_scan = getPref($data_dir, $username, 'filters_spam_scan');
 450     $filters_spam_folder = getPref($data_dir, $username, 'filters_spam_folder');
 451     $filters = load_spam_filters();
 452
 453     if ($SpamFilters_SharedCache) {
 454        filters_LoadCache();
 455     }
 456
 457     $run = false;
 458
 459     foreach ($filters as $Value) {
 460         if ($Value['enabled']) {
 461             $run = true;
 462             break;
 463         }
 464     }
 465
 466     // short-circuit
 467     if (!$run) {
 468         return;
 469     }
 470
 471     // Ask for a big list of all "Received" headers in the inbox with
 472     // flags for each message.  Kinda big.
 473
 474     if ($filters_spam_scan == 'new') {
 475         $search_array = array();
 476         $read = sqimap_run_command($imap_stream, 'SEARCH UNSEEN', true, $response, $message, TRUE);
 477         if (isset($read[0])) {
 478             for ($i = 0, $iCnt = count($read); $i < $iCnt; ++$i) {
 479                 if (preg_match("/^\* SEARCH (.+)$/", $read[$i], $regs)) {
 480                     $search_array = explode(' ', trim($regs[1]));
 481                     break;
 482                 }
 483             }
 484         }
 485     }
 486     if ($filters_spam_scan == 'new' && count($search_array)) {
 487         $headers = sqimap_get_small_header_list ($imap_stream, $search_array, array('Received'),array());
 488     } else if ($filters_spam_scan != 'new') {
 489         $headers = sqimap_get_small_header_list ($imap_stream, null , array('Received'),array());
 490     } else {
 491         return;
 492     }
 493     if (!count($headers)) {
 494         return;
 495     }
 496     $bulkquery = (strlen($SpamFilters_BulkQuery) > 0 ? true : false);
 497     $IPs = array();
 498     $aSpamIds = array();
 499     foreach ($headers as $id => $aValue) {
 500         if (isset($aValue['UID'])) {
 501             $MsgNum = $aValue['UID'];
 502         } else {
 503             $MsgNum = $id;
 504         }
 505         // Look through all of the Received headers for IP addresses
 506         if (isset($aValue['RECEIVED'])) {
 507             foreach ($aValue['RECEIVED'] as $received) {
 508                 // Check to see if this line is the right "Received from" line
 509                 // to check
 510
 511                 // $aValue['Received'] is an array with all the received lines.
 512                 // We should check them from bottom to top and only check the first 2.
 513                 // Currently we check only the header where $SpamFilters_YourHop in occures
 514
 515                 if (is_int(strpos($received, $SpamFilters_YourHop))) {
 516                     if (preg_match('/([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})/',$received,$aMatch)) {
 517                         $isspam = false;
 518                         if (filters_spam_check_site($aMatch[1],$aMatch[2],$aMatch[3],$aMatch[4],$filters)) {
 519                             $aSpamIds[] = $MsgNum;
 520                             $isspam = true;
 521                         }
 522
 523                         if ($bulkquery) {
 524                             array_shift($aMatch);
 525                             $IP = explode('.', $aMatch);
 526                             foreach ($filters as $key => $value) {
 527                                 if ($filters[$key]['enabled'] && $filters[$key]['dns']) {
 528                                     if (strlen($SpamFilters_DNScache[$IP.'.'.$filters[$key]['dns']]) == 0) {
 529                                         $IPs[$IP] = true;
 530                                         break;
 531                                     }
 532                                 }
 533                             }
 534                         }
 535                         // If we've checked one IP and YourHop is
 536                         // just a space
 537                         if ($SpamFilters_YourHop == ' ' || $isspam) {
 538                             break;  // don't check any more
 539                         }
 540                     }
 541                 }
 542             }
 543         }
 544     }
 545     // Lookie!  It's spam!  Yum!
 546     if (count($aSpamIds) && sqimap_mailbox_exists($imap_stream, $filters_spam_folder)) {
 547         if (!sqimap_msgs_list_move($imap_stream, $aSpamIds, $filters_spam_folder)) {
 548            // if errors occurred, don't try to filter again during this session
 549            sqsession_register(TRUE, 'filters_error');
 550            global $color;
 551            error_box(_("A problem occurred filtering messages. Check filter settings and account quota if applicable. Filtering is disabled for the remainder of this login session."), $color);
 552         }
 553
 554         // expunge even in the case of errors, in case some
 555         // messages were filtered before the error happened
 556         sqimap_mailbox_expunge($imap_stream, 'INBOX');
 557     }
 558
 559     if ($bulkquery && count($IPs)) {
 560         filters_bulkquery($filters, $IPs);
 561     }
 562
 563     if ($SpamFilters_SharedCache) {
 564        filters_SaveCache();
 565     } else {
 566        sqsession_register($SpamFilters_DNScache, 'SpamFilters_DNScache');
 567     }
 568 }
 569
 570 /**
 571  * Does the loop through each enabled filter for the specified IP address.
 572  * IP format:  $a.$b.$c.$d
 573  * @param int $a First subset of IP
 574  * @param int $b Second subset of IP
 575  * @param int $c Third subset of IP
 576  * @param int $d Forth subset of IP
 577  * @param array $filters The Spam Filters
 578  * @return boolean Whether the IP is Spam
 579  * @access private
 580  */
 581 function filters_spam_check_site($a, $b, $c, $d, &$filters) {
 582     global $SpamFilters_DNScache, $SpamFilters_CacheTTL;
 583     foreach ($filters as $key => $value) {
 584         if ($filters[$key]['enabled']) {
 585             if ($filters[$key]['dns']) {
 586
 587                 /**
 588                  * RFC allows . on end of hostname to force domain lookup to
 589                  * not use search domain from resolv.conf, i.e. to ensure
 590                  * search domain isn't used if no hostname is found
 591                  */
 592                 $filter_revip = $d . '.' . $c . '.' . $b . '.' . $a . '.' .
 593                                 $filters[$key]['dns'] . '.';
 594
 595                 if(!isset($SpamFilters_DNScache[$filter_revip]['L']))
 596                         $SpamFilters_DNScache[$filter_revip]['L'] = '';
 597
 598                 if(!isset($SpamFilters_DNScache[$filter_revip]['T']))
 599                         $SpamFilters_DNScache[$filter_revip]['T'] = '';
 600
 601                 if (strlen($SpamFilters_DNScache[$filter_revip]['L']) == 0) {
 602                     $SpamFilters_DNScache[$filter_revip]['L'] =
 603                                     gethostbyname($filter_revip);
 604                     $SpamFilters_DNScache[$filter_revip]['T'] =
 605                                        time() + $SpamFilters_CacheTTL;
 606                 }
 607
 608                 /**
 609                  * gethostbyname returns ip if resolved, or returns original
 610                  * host supplied to function if there is no resolution
 611                  */
 612                 if ($SpamFilters_DNScache[$filter_revip]['L'] != $filter_revip) {
 613                     return 1;
 614                 }
 615             }
 616         }
 617     }
 618     return 0;
 619 }
 620
 621 /**
 622  * Loads the filters from the user preferences
 623  * @return array All the user filters
 624  * @access private
 625  */
 626 function load_filters() {
 627     global $data_dir, $username;
 628
 629     $filters = array();
 630     for ($i = 0; $fltr = getPref($data_dir, $username, 'filter' . $i); $i++) {
 631         $ary = explode(',', $fltr);
 632         $filters[$i]['where'] = $ary[0];
 633         $filters[$i]['what'] = str_replace('###COMMA###', ',', $ary[1]);
 634         $filters[$i]['folder'] = $ary[2];
 635     }
 636     return $filters;
 637 }
 638
 639 /**
 640  * Loads the Spam Filters and checks the preferences for the enabled status
 641  * @return array All the spam filters
 642  * @access private
 643  */
 644 function load_spam_filters() {
 645     global $data_dir, $username, $SpamFilters_ShowCommercial;
 646
 647     if ($SpamFilters_ShowCommercial) {
 648         $filters['MAPS RBL']['prefname'] = 'filters_spam_maps_rbl';
 649         $filters['MAPS RBL']['name'] = 'MAPS Realtime Blackhole List';
 650         $filters['MAPS RBL']['link'] = 'http://www.mail-abuse.org/rbl/';
 651         $filters['MAPS RBL']['dns'] = 'blackholes.mail-abuse.org';
 652         $filters['MAPS RBL']['result'] = '127.0.0.2';
 653         $filters['MAPS RBL']['comment'] =
 654             _("COMMERCIAL - This list contains servers that are verified spam senders. It is a pretty reliable list to scan spam from.");
 655
 656         $filters['MAPS RSS']['prefname'] = 'filters_spam_maps_rss';
 657         $filters['MAPS RSS']['name'] = 'MAPS Relay Spam Stopper';
 658         $filters['MAPS RSS']['link'] = 'http://www.mail-abuse.org/rss/';
 659         $filters['MAPS RSS']['dns'] = 'relays.mail-abuse.org';
 660         $filters['MAPS RSS']['result'] = '127.0.0.2';
 661         $filters['MAPS RSS']['comment'] =
 662             _("COMMERCIAL - Servers that are configured (or misconfigured) to allow spam to be relayed through their system will be banned with this. Another good one to use.");
 663
 664         $filters['MAPS DUL']['prefname'] = 'filters_spam_maps_dul';
 665         $filters['MAPS DUL']['name'] = 'MAPS Dial-Up List';
 666         $filters['MAPS DUL']['link'] = 'http://www.mail-abuse.org/dul/';
 667         $filters['MAPS DUL']['dns'] = 'dialups.mail-abuse.org';
 668         $filters['MAPS DUL']['result'] = '127.0.0.3';
 669         $filters['MAPS DUL']['comment'] =
 670             _("COMMERCIAL - Dial-up users are often filtered out since they should use their ISP's mail servers to send mail. Spammers typically get a dial-up account and send spam directly from there.");
 671
 672         $filters['MAPS RBLplus-RBL']['prefname'] = 'filters_spam_maps_rblplus_rbl';
 673         $filters['MAPS RBLplus-RBL']['name'] = 'MAPS RBL+ RBL List';
 674         $filters['MAPS RBLplus-RBL']['link'] = 'http://www.mail-abuse.org/';
 675         $filters['MAPS RBLplus-RBL']['dns'] = 'rbl-plus.mail-abuse.org';
 676         $filters['MAPS RBLplus-RBL']['result'] = '127.0.0.2';
 677         $filters['MAPS RBLplus-RBL']['comment'] =
 678             _("COMMERCIAL - RBL+ Blackhole entries.");
 679
 680         $filters['MAPS RBLplus-RSS']['prefname'] = 'filters_spam_maps_rblplus_rss';
 681         $filters['MAPS RBLplus-RSS']['name'] = 'MAPS RBL+ List RSS entries';
 682         $filters['MAPS RBLplus-RSS']['link'] = 'http://www.mail-abuse.org/';
 683         $filters['MAPS RBLplus-RSS']['dns'] = 'rbl-plus.mail-abuse.org';
 684         $filters['MAPS RBLplus-RSS']['result'] = '127.0.0.2';
 685         $filters['MAPS RBLplus-RSS']['comment'] =
 686             _("COMMERCIAL - RBL+ OpenRelay entries.");
 687
 688         $filters['MAPS RBLplus-DUL']['prefname'] = 'filters_spam_maps_rblplus_dul';
 689         $filters['MAPS RBLplus-DUL']['name'] = 'MAPS RBL+ List DUL entries';
 690         $filters['MAPS RBLplus-DUL']['link'] = 'http://www.mail-abuse.org/';
 691         $filters['MAPS RBLplus-DUL']['dns'] = 'rbl-plus.mail-abuse.org';
 692         $filters['MAPS RBLplus-DUL']['result'] = '127.0.0.3';
 693         $filters['MAPS RBLplus-DUL']['comment'] =
 694             _("COMMERCIAL - RBL+ Dial-up entries.");
 695     }
 696
 697     $filters['FiveTen Direct']['prefname'] = 'filters_spam_fiveten_src';
 698     $filters['FiveTen Direct']['name'] = 'Five-Ten-sg.com Direct SPAM Sources';
 699     $filters['FiveTen Direct']['link'] = 'http://www.five-ten-sg.com/blackhole.php';
 700     $filters['FiveTen Direct']['dns'] = 'blackholes.five-ten-sg.com';
 701     $filters['FiveTen Direct']['result'] = '127.0.0.2';
 702     $filters['FiveTen Direct']['comment'] =
 703         _("FREE - Five-Ten-sg.com - Direct SPAM sources.");
 704
 705     $filters['FiveTen DUL']['prefname'] = 'filters_spam_fiveten_dul';
 706     $filters['FiveTen DUL']['name'] = 'Five-Ten-sg.com DUL Lists';
 707     $filters['FiveTen DUL']['link'] = 'http://www.five-ten-sg.com/blackhole.php';
 708     $filters['FiveTen DUL']['dns'] = 'blackholes.five-ten-sg.com';
 709     $filters['FiveTen DUL']['result'] = '127.0.0.3';
 710     $filters['FiveTen DUL']['comment'] =
 711         _("FREE - Five-Ten-sg.com - Dial-up lists - includes some DSL IPs.");
 712
 713     $filters['FiveTen Unc. OptIn']['prefname'] = 'filters_spam_fiveten_oi';
 714     $filters['FiveTen Unc. OptIn']['name'] = 'Five-Ten-sg.com Unconfirmed OptIn Lists';
 715     $filters['FiveTen Unc. OptIn']['link'] = 'http://www.five-ten-sg.com/blackhole.php';
 716     $filters['FiveTen Unc. OptIn']['dns'] = 'blackholes.five-ten-sg.com';
 717     $filters['FiveTen Unc. OptIn']['result'] = '127.0.0.4';
 718     $filters['FiveTen Unc. OptIn']['comment'] =
 719         _("FREE - Five-Ten-sg.com - Bulk mailers that do not use confirmed opt-in.");
 720
 721     $filters['FiveTen Others']['prefname'] = 'filters_spam_fiveten_oth';
 722     $filters['FiveTen Others']['name'] = 'Five-Ten-sg.com Other Misc. Servers';
 723     $filters['FiveTen Others']['link'] = 'http://www.five-ten-sg.com/blackhole.php';
 724     $filters['FiveTen Others']['dns'] = 'blackholes.five-ten-sg.com';
 725     $filters['FiveTen Others']['result'] = '127.0.0.5';
 726     $filters['FiveTen Others']['comment'] =
 727         _("FREE - Five-Ten-sg.com - Other misc. servers.");
 728
 729     $filters['FiveTen Single Stage']['prefname'] = 'filters_spam_fiveten_ss';
 730     $filters['FiveTen Single Stage']['name'] = 'Five-Ten-sg.com Single Stage Servers';
 731     $filters['FiveTen Single Stage']['link'] = 'http://www.five-ten-sg.com/blackhole.php';
 732     $filters['FiveTen Single Stage']['dns'] = 'blackholes.five-ten-sg.com';
 733     $filters['FiveTen Single Stage']['result'] = '127.0.0.6';
 734     $filters['FiveTen Single Stage']['comment'] =
 735         _("FREE - Five-Ten-sg.com - Single Stage servers.");
 736
 737     $filters['FiveTen SPAM Support']['prefname'] = 'filters_spam_fiveten_supp';
 738     $filters['FiveTen SPAM Support']['name'] = 'Five-Ten-sg.com SPAM Support Servers';
 739     $filters['FiveTen SPAM Support']['link'] = 'http://www.five-ten-sg.com/blackhole.php';
 740     $filters['FiveTen SPAM Support']['dns'] = 'blackholes.five-ten-sg.com';
 741     $filters['FiveTen SPAM Support']['result'] = '127.0.0.7';
 742     $filters['FiveTen SPAM Support']['comment'] =
 743         _("FREE - Five-Ten-sg.com - SPAM Support servers.");
 744
 745     $filters['FiveTen Web forms']['prefname'] = 'filters_spam_fiveten_wf';
 746     $filters['FiveTen Web forms']['name'] = 'Five-Ten-sg.com Web Form IPs';
 747     $filters['FiveTen Web forms']['link'] = 'http://www.five-ten-sg.com/blackhole.php';
 748     $filters['FiveTen Web forms']['dns'] = 'blackholes.five-ten-sg.com';
 749     $filters['FiveTen Web forms']['result'] = '127.0.0.8';
 750     $filters['FiveTen Web forms']['comment'] =
 751         _("FREE - Five-Ten-sg.com - Web Form IPs.");
 752
 753     $filters['Dorkslayers']['prefname'] = 'filters_spam_dorks';
 754     $filters['Dorkslayers']['name'] = 'Dorkslayers Lists';
 755     $filters['Dorkslayers']['link'] = 'http://www.dorkslayers.com';
 756     $filters['Dorkslayers']['dns'] = 'orbs.dorkslayers.com';
 757     $filters['Dorkslayers']['result'] = '127.0.0.2';
 758     $filters['Dorkslayers']['comment'] =
 759         _("FREE - Dorkslayers appears to include only really bad open relays outside the US to avoid being sued. Interestingly enough, their website recommends you NOT use their service.");
 760
 761     $filters['SPAMhaus']['prefname'] = 'filters_spam_spamhaus';
 762     $filters['SPAMhaus']['name'] = 'SPAMhaus Lists';
 763     $filters['SPAMhaus']['link'] = 'http://www.spamhaus.org';
 764     $filters['SPAMhaus']['dns'] = 'sbl.spamhaus.org';
 765     $filters['SPAMhaus']['result'] = '127.0.0.2';
 766     $filters['SPAMhaus']['comment'] =
 767         _("FREE - SPAMhaus - A list of well-known SPAM sources.");
 768
 769     $filters['SPAMcop']['prefname'] = 'filters_spam_spamcop';
 770     $filters['SPAMcop']['name'] = 'SPAM Cop Lists';
 771     $filters['SPAMcop']['link'] = 'http://spamcop.net/bl.shtml';
 772     $filters['SPAMcop']['dns'] = 'bl.spamcop.net';
 773     $filters['SPAMcop']['result'] = '127.0.0.2';
 774     $filters['SPAMcop']['comment'] =
 775         _("FREE, for now - SpamCop - An interesting solution that lists servers that have a very high spam to legit email ratio (85 percent or more).");
 776
 777     $filters['dev.null.dk']['prefname'] = 'filters_spam_devnull';
 778     $filters['dev.null.dk']['name'] = 'dev.null.dk Lists';
 779     $filters['dev.null.dk']['link'] = 'http://dev.null.dk/';
 780     $filters['dev.null.dk']['dns'] = 'dev.null.dk';
 781     $filters['dev.null.dk']['result'] = '127.0.0.2';
 782     $filters['dev.null.dk']['comment'] =
 783         _("FREE - dev.null.dk - I don't have any detailed info on this list.");
 784
 785     $filters['visi.com']['prefname'] = 'filters_spam_visi';
 786     $filters['visi.com']['name'] = 'visi.com Relay Stop List';
 787     $filters['visi.com']['link'] = 'http://relays.visi.com';
 788     $filters['visi.com']['dns'] = 'relays.visi.com';
 789     $filters['visi.com']['result'] = '127.0.0.2';
 790     $filters['visi.com']['comment'] =
 791         _("FREE - visi.com - Relay Stop List. Very conservative OpenRelay List.");
 792
 793     $filters['ahbl.org Open Relays']['prefname'] = 'filters_spam_2mb_or';
 794     $filters['ahbl.org Open Relays']['name'] = 'ahbl.org Open Relays List';
 795     $filters['ahbl.org Open Relays']['link'] = 'http://www.ahbl.org/';
 796     $filters['ahbl.org Open Relays']['dns'] = 'dnsbl.ahbl.org';
 797     $filters['ahbl.org Open Relays']['result'] = '127.0.0.2';
 798     $filters['ahbl.org Open Relays']['comment'] =
 799         _("FREE - ahbl.org Open Relays - Another list of Open Relays.");
 800
 801     $filters['ahbl.org SPAM Source']['prefname'] = 'filters_spam_2mb_ss';
 802     $filters['ahbl.org SPAM Source']['name'] = 'ahbl.org SPAM Source List';
 803     $filters['ahbl.org SPAM Source']['link'] = 'http://www.ahbl.org/';
 804     $filters['ahbl.org SPAM Source']['dns'] = 'dnsbl.ahbl.org';
 805     $filters['ahbl.org SPAM Source']['result'] = '127.0.0.4';
 806     $filters['ahbl.org SPAM Source']['comment'] =
 807         _("FREE - ahbl.org SPAM Source - List of Direct SPAM Sources.");
 808
 809     $filters['ahbl.org SPAM ISPs']['prefname'] = 'filters_spam_2mb_isp';
 810     $filters['ahbl.org SPAM ISPs']['name'] = 'ahbl.org SPAM-friendly ISP List';
 811     $filters['ahbl.org SPAM ISPs']['link'] = 'http://www.ahbl.org/';
 812     $filters['ahbl.org SPAM ISPs']['dns'] = 'dnsbl.ahbl.org';
 813     $filters['ahbl.org SPAM ISPs']['result'] = '127.0.0.7';
 814     $filters['ahbl.org SPAM ISPs']['comment'] =
 815         _("FREE - ahbl.org SPAM ISPs - List of SPAM-friendly ISPs.");
 816
 817     $filters['Leadmon DUL']['prefname'] = 'filters_spam_lm_dul';
 818     $filters['Leadmon DUL']['name'] = 'Leadmon.net DUL List';
 819     $filters['Leadmon DUL']['link'] = 'http://www.leadmon.net/spamguard/';
 820     $filters['Leadmon DUL']['dns'] = 'spamguard.leadmon.net';
 821     $filters['Leadmon DUL']['result'] = '127.0.0.2';
 822     $filters['Leadmon DUL']['comment'] =
 823         _("FREE - Leadmon DUL - Another list of Dial-up or otherwise dynamically assigned IPs.");
 824
 825     $filters['Leadmon SPAM Source']['prefname'] = 'filters_spam_lm_ss';
 826     $filters['Leadmon SPAM Source']['name'] = 'Leadmon.net SPAM Source List';
 827     $filters['Leadmon SPAM Source']['link'] = 'http://www.leadmon.net/spamguard/';
 828     $filters['Leadmon SPAM Source']['dns'] = 'spamguard.leadmon.net';
 829     $filters['Leadmon SPAM Source']['result'] = '127.0.0.3';
 830     $filters['Leadmon SPAM Source']['comment'] =
 831         _("FREE - Leadmon SPAM Source - List of IPs Leadmon.net has received SPAM directly from.");
 832
 833     $filters['Leadmon Bulk Mailers']['prefname'] = 'filters_spam_lm_bm';
 834     $filters['Leadmon Bulk Mailers']['name'] = 'Leadmon.net Bulk Mailers List';
 835     $filters['Leadmon Bulk Mailers']['link'] = 'http://www.leadmon.net/spamguard/';
 836     $filters['Leadmon Bulk Mailers']['dns'] = 'spamguard.leadmon.net';
 837     $filters['Leadmon Bulk Mailers']['result'] = '127.0.0.4';
 838     $filters['Leadmon Bulk Mailers']['comment'] =
 839         _("FREE - Leadmon Bulk Mailers - Bulk mailers that do not require confirmed opt-in or that have allowed known spammers to become clients and abuse their services.");
 840
 841     $filters['Leadmon Open Relays']['prefname'] = 'filters_spam_lm_or';
 842     $filters['Leadmon Open Relays']['name'] = 'Leadmon.net Open Relays List';
 843     $filters['Leadmon Open Relays']['link'] = 'http://www.leadmon.net/spamguard/';
 844     $filters['Leadmon Open Relays']['dns'] = 'spamguard.leadmon.net';
 845     $filters['Leadmon Open Relays']['result'] = '127.0.0.5';
 846     $filters['Leadmon Open Relays']['comment'] =
 847         _("FREE - Leadmon Open Relays - Single Stage Open Relays that are not listed on other active RBLs.");
 848
 849     $filters['Leadmon Multi-stage']['prefname'] = 'filters_spam_lm_ms';
 850     $filters['Leadmon Multi-stage']['name'] = 'Leadmon.net Multi-Stage Relay List';
 851     $filters['Leadmon Multi-stage']['link'] = 'http://www.leadmon.net/spamguard/';
 852     $filters['Leadmon Multi-stage']['dns'] = 'spamguard.leadmon.net';
 853     $filters['Leadmon Multi-stage']['result'] = '127.0.0.6';
 854     $filters['Leadmon Multi-stage']['comment'] =
 855         _("FREE - Leadmon Multi-stage - Multi-Stage Open Relays that are not listed on other active RBLs and that have sent SPAM to Leadmon.net.");
 856
 857     $filters['Leadmon SpamBlock']['prefname'] = 'filters_spam_lm_sb';
 858     $filters['Leadmon SpamBlock']['name'] = 'Leadmon.net SpamBlock Sites List';
 859     $filters['Leadmon SpamBlock']['link'] = 'http://www.leadmon.net/spamguard/';
 860     $filters['Leadmon SpamBlock']['dns'] = 'spamguard.leadmon.net';
 861     $filters['Leadmon SpamBlock']['result'] = '127.0.0.7';
 862     $filters['Leadmon SpamBlock']['comment'] =
 863         _("FREE - Leadmon SpamBlock - Sites on this listing have sent Leadmon.net direct SPAM from IPs in netblocks where the entire block has no DNS mappings. It's a list of BLOCKS of IPs being used by people who have SPAMmed Leadmon.net.");
 864
 865     $filters['NJABL Open Relays']['prefname'] = 'filters_spam_njabl_or';
 866     $filters['NJABL Open Relays']['name'] = 'NJABL Open Relay/Direct Spam Source List';
 867     $filters['NJABL Open Relays']['link'] = 'http://www.njabl.org/';
 868     $filters['NJABL Open Relays']['dns'] = 'dnsbl.njabl.org';
 869     $filters['NJABL Open Relays']['result'] = '127.0.0.2';
 870     $filters['NJABL Open Relays']['comment'] =
 871         _("FREE, for now - Not Just Another Blacklist - Both Open Relays and Direct SPAM Sources.");
 872
 873     $filters['NJABL DUL']['prefname'] = 'filters_spam_njabl_dul';
 874     $filters['NJABL DUL']['name'] = 'NJABL Dial-ups List';
 875     $filters['NJABL DUL']['link'] = 'http://www.njabl.org/';
 876     $filters['NJABL DUL']['dns'] = 'dnsbl.njabl.org';
 877     $filters['NJABL DUL']['result'] = '127.0.0.3';
 878     $filters['NJABL DUL']['comment'] =
 879         _("FREE, for now - Not Just Another Blacklist - Dial-up IPs.");
 880
 881     foreach ($filters as $Key => $Value) {
 882         $filters[$Key]['enabled'] = (bool)getPref($data_dir, $username, $filters[$Key]['prefname']);
 883     }
 884
 885     return $filters;
 886 }
 887
 888 /**
 889  * Removes a User filter
 890  * @param int $id ID of the filter to remove
 891  * @access private
 892  */
 893 function remove_filter ($id) {
 894     global $data_dir, $username;
 895
 896     while ($nextFilter = getPref($data_dir, $username, 'filter' . ($id + 1))) {
 897         setPref($data_dir, $username, 'filter' . $id, $nextFilter);
 898         $id ++;
 899     }
 900
 901     removePref($data_dir, $username, 'filter' . $id);
 902 }
 903
 904 /**
 905  * Swaps two filters
 906  * @param int $id1 ID of first filter to swap
 907  * @param int $id2 ID of second filter to swap
 908  * @access private
 909  */
 910 function filter_swap($id1, $id2) {
 911     global $data_dir, $username;
 912
 913     $FirstFilter = getPref($data_dir, $username, 'filter' . $id1);
 914     $SecondFilter = getPref($data_dir, $username, 'filter' . $id2);
 915
 916     if ($FirstFilter && $SecondFilter) {
 917         setPref($data_dir, $username, 'filter' . $id2, $FirstFilter);
 918         setPref($data_dir, $username, 'filter' . $id1, $SecondFilter);
 919     }
 920 }
 921
 922 /**
 923  * This updates the filter rules when renaming or deleting folders
 924  * @param array $args
 925  * @access private
 926  */
 927 function update_for_folder ($args) {
 928     $old_folder = $args[0];
 929     $new_folder = $args[2];
 930     $action = $args[1];
 931     global $data_dir, $username;
 932     $filters = array();
 933     $filters = load_filters();
 934     $filter_count = count($filters);
 935     $p = 0;
 936     for ($i = 0; $i < $filter_count; $i++) {
 937         if (!empty($filters)) {
 938             if ($old_folder == $filters[$i]['folder']) {
 939                 if ($action == 'rename') {
 940                     $filters[$i]['folder'] = $new_folder;
 941                     setPref($data_dir, $username, 'filter'.$i,
 942                     $filters[$i]['where'].','.$filters[$i]['what'].','.$new_folder);
 943                 }
 944                 elseif ($action == 'delete') {
 945                     remove_filter($p);
 946                     $p = $p-1;
 947                 }
 948             }
 949         $p++;
 950         }
 951     }
 952 }
 953
 954 /**
 955  * Display formated error message
 956  * @param string $string text message
 957  * @return string html formated text message
 958  * @access private
 959  */
 960 function do_error($string) {
 961     global $color;
 962     echo "<p align=\"center\"><font color=\"$color[2]\">";
 963     echo $string;
 964     echo "</font></p>\n";
 965 }