functions/mime.php

   1 <?php
   2
   3 /**
   4  * mime.php
   5  *
   6  * Copyright (c) 1999-2002 The SquirrelMail Project Team
   7  * Licensed under the GNU GPL. For full terms see the file COPYING.
   8  *
   9  * This contains the functions necessary to detect and decode MIME
  10  * messages.
  11  *
  12  * $Id$
  13  */
  14
  15 require_once('../functions/imap.php');
  16 require_once('../functions/attachment_common.php');
  17
  18 /* --------------------------------------------------------------------------------- */
  19 /* MIME DECODING                                                                     */
  20 /* --------------------------------------------------------------------------------- */
  21
  22 /* This function gets the structure of a message and stores it in the "message" class.
  23  * It will return this object for use with all relevant header information and
  24  * fully parsed into the standard "message" object format.
  25  */
  26
  27 function mime_structure ($bodystructure, $flags=array()) {
  28
  29     // isolate the body structure and remove beginning and end parenthesis
  30     $read = trim(substr ($bodystructure, strpos(strtolower($bodystructure), 'bodystructure') + 13));
  31     $msg = &new message();
  32     $read = trim(substr ($read, 0, -1));
  33     $res = $msg->parseStructure($read);
  34     $msg = $res[0];
  35     $msg->setEnt('0');
  36     if (count($flags)) {
  37         foreach ($flags as $flag) {
  38             $char = strtoupper($flag{1});
  39             switch ($char) {
  40             case 'S':
  41                 if (strtolower($flag) == '\\seen') {
  42                     $msg->is_seen = true;
  43                 }
  44                 break;
  45             case 'A':
  46                 if (strtolower($flag) == '\\answered') {
  47                     $msg->is_answered = true;
  48                 }
  49                 break;
  50             case 'D':
  51                 if (strtolower($flag) == '\\deleted') {
  52                     $msg->is_deleted = true;
  53                 }
  54                 break;
  55             case 'F':
  56                 if (strtolower($flag) == '\\flagged') {
  57                     $msg->is_flagged = true;
  58                 }
  59                 break;
  60             case 'M':
  61                 if (strtolower($flag) == '$mdnsent') {
  62                     $msg->is_mdnsent = true;
  63                 }
  64                 break;
  65             default:
  66                 break;
  67             }
  68         }
  69     }
  70     //    listEntities($msg);
  71     return( $msg );
  72 }
  73
  74 /* this starts the parsing of a particular structure.  It is called recursively,
  75  * so it can be passed different structures.  It returns an object of type
  76  * $message.
  77  * First, it checks to see if it is a multipart message.  If it is, then it
  78  * handles that as it sees is necessary.  If it is just a regular entity,
  79  * then it parses it and adds the necessary header information (by calling out
  80  * to mime_get_elements()
  81  */
  82
  83 function mime_fetch_body($imap_stream, $id, $ent_id) {
  84     global $uid_support;
  85     /*
  86      * do a bit of error correction.  If we couldn't find the entity id, just guess
  87      * that it is the first one.  That is usually the case anyway.
  88      */
  89     if (!$ent_id) {
  90         $ent_id = 1;
  91     }
  92     $cmd = "FETCH $id BODY[$ent_id]";
  93
  94     $data = sqimap_run_command ($imap_stream, $cmd, true, $response, $message, $uid_support);
  95     do {
  96         $topline = trim(array_shift( $data ));
  97     } while( $topline && $topline[0] == '*' && !preg_match( '/\* [0-9]+ FETCH.*/i', $topline )) ;
  98
  99     $wholemessage = implode('', $data);
 100     if (ereg('\\{([^\\}]*)\\}', $topline, $regs)) {
 101
 102         $ret = substr( $wholemessage, 0, $regs[1] );
 103         /*
 104             There is some information in the content info header that could be important
 105             in order to parse html messages. Let's get them here.
 106         */
 107         if ( $ret{0} == '<' ) {
 108             $data = sqimap_run_command ($imap_stream, "FETCH $id BODY[$ent_id.MIME]", true, $response, $message, $uid_support);
 109         }
 110     } else if (ereg('"([^"]*)"', $topline, $regs)) {
 111         $ret = $regs[1];
 112     } else {
 113         global $where, $what, $mailbox, $passed_id, $startMessage;
 114         $par = 'mailbox=' . urlencode($mailbox) . "&amp;passed_id=$passed_id";
 115         if (isset($where) && isset($what)) {
 116             $par .= '&amp;where='. urlencode($where) . "&amp;what=" . urlencode($what);
 117         } else {
 118             $par .= "&amp;startMessage=$startMessage&amp;show_more=0";
 119         }
 120         $par .= '&amp;response=' . urlencode($response) .
 121                 '&amp;message=' . urlencode($message).
 122                 '&amp;topline=' . urlencode($topline);
 123
 124         echo   '<tt><br>' .
 125                '<table width="80%"><tr>' .
 126                '<tr><td colspan=2>' .
 127                _("Body retrieval error. The reason for this is most probably that the message is malformed. Please help us making future versions better by submitting this message to the developers knowledgebase!") .
 128                " <A HREF=\"../src/retrievalerror.php?$par\"><br>" .
 129                _("Submit message") . '</A><BR>&nbsp;' .
 130                '</td></tr>' .
 131                '<td><b>' . _("Command:") . "</td><td>$cmd</td></tr>" .
 132                '<td><b>' . _("Response:") . "</td><td>$response</td></tr>" .
 133                '<td><b>' . _("Message:") . "</td><td>$message</td></tr>" .
 134                '<td><b>' . _("FETCH line:") . "</td><td>$topline</td></tr>" .
 135                "</table><BR></tt></font><hr>";
 136
 137         $data = sqimap_run_command ($imap_stream, "FETCH $passed_id BODY[]", true, $response, $message, $uid_support);
 138         array_shift($data);
 139         $wholemessage = implode('', $data);
 140
 141         $ret = $wholemessage;
 142     }
 143     return( $ret );
 144 }
 145
 146 function mime_print_body_lines ($imap_stream, $id, $ent_id, $encoding) {
 147     global $uid_support;
 148     // do a bit of error correction.  If we couldn't find the entity id, just guess
 149     // that it is the first one.  That is usually the case anyway.
 150     if (!$ent_id) {
 151         $ent_id = 1;
 152     }
 153     $sid = sqimap_session_id($uid_support);
 154     // Don't kill the connection if the browser is over a dialup
 155     // and it would take over 30 seconds to download it.
 156
 157     // don´t call set_time_limit in safe mode.
 158     if (!ini_get("safe_mode")) {
 159         set_time_limit(0);
 160     }
 161     if ($uid_support) {
 162        $sid_s = substr($sid,0,strpos($sid, ' '));
 163     } else {
 164        $sid_s = $sid;
 165     }
 166
 167     $body = mime_fetch_body ($imap_stream, $id, $ent_id);
 168     echo decodeBody($body, $encoding);
 169     return;
 170 /*
 171     fputs ($imap_stream, "$sid FETCH $id BODY[$ent_id]\r\n");
 172     $cnt = 0;
 173     $continue = true;
 174     $read = fgets ($imap_stream,8192);
 175
 176
 177     // This could be bad -- if the section has sqimap_session_id() . ' OK'
 178     // or similar, it will kill the download.
 179     while (!ereg("^".$sid_s." (OK|BAD|NO)(.*)$", $read, $regs)) {
 180         if (trim($read) == ')==') {
 181             $read1 = $read;
 182             $read = fgets ($imap_stream,4096);
 183             if (ereg("^".$sid." (OK|BAD|NO)(.*)$", $read, $regs)) {
 184                 return;
 185             } else {
 186                 echo decodeBody($read1, $encoding) .
 187                      decodeBody($read, $encoding);
 188             }
 189         } else if ($cnt) {
 190             echo decodeBody($read, $encoding);
 191         }
 192         $read = fgets ($imap_stream,4096);
 193         $cnt++;
 194 //      break;
 195     }
 196 */
 197 }
 198
 199 /* -[ END MIME DECODING ]----------------------------------------------------------- */
 200
 201 /* findDisplayEntity
 202  * Checks to see if $message contains content of type $type0/$type1
 203  * returns the first entity number it finds of that type, or NULL if
 204  * none is found.  Takes optional argument $start to allow the caller
 205  * to continue where they left off
 206  */
 207 function findDisplayEntity($message, $type0, $type1, $start=0) {
 208     if ($message) {
 209         for ($i = $start;isset($message->entities[$i]); $i++) {
 210             $entity = $message->entities[$i];
 211             if ($entity->type0 == $type0 && $entity->type1 == $type1) {
 212                 return $i;
 213             }
 214         }
 215     }
 216     return NULL;
 217 }
 218
 219 // This is here for debugging purposese.  It will print out a list
 220 // of all the entity IDs that are in the $message object.
 221
 222 function listEntities ($message) {
 223   if ($message) {
 224     echo "<tt>" . $message->entity_id . ' : ' . $message->type0 . '/' . $message->type1 . ' parent = '. $message->parent->entity_id. '<br>';
 225     for ($i = 0;isset($message->entities[$i]); $i++) {
 226        echo "$i : ";
 227        $msg = listEntities($message->entities[$i]);
 228
 229        if ($msg) {
 230           echo "return: ";
 231           return $msg;
 232        }
 233     }
 234   }
 235 }
 236
 237 function getPriorityStr($priority) {
 238    $priority_level = substr($priority,0,1);
 239
 240    switch($priority_level) {
 241      /* check for a higher then normal priority. */
 242      case '1':
 243      case '2':
 244         $priority_string = _("High");
 245         break;
 246
 247       /* check for a lower then normal priority. */
 248      case '4':
 249      case '5':
 250         $priority_string = _("Low");
 251         break;
 252
 253      /* check for a normal priority. */
 254      case '3':
 255      default:
 256         $priority_level = '3';
 257         $priority_string = _("Normal");
 258         break;
 259
 260    }
 261    return $priority_string;
 262 }
 263
 264 /* returns a $message object for a particular entity id */
 265 function getEntity ($message, $ent_id) {
 266     return $message->getEntity($ent_id);
 267 }
 268
 269 /*
 270  * translateText
 271  * Extracted from strings.php 23/03/2002
 272  */
 273
 274 function translateText(&$body, $wrap_at, $charset) {
 275     global $where, $what; /* from searching */
 276     global $color; /* color theme */
 277
 278     require_once('../functions/url_parser.php');
 279
 280     $body_ary = explode("\n", $body);
 281     $PriorQuotes = 0;
 282     for ($i=0; $i < count($body_ary); $i++) {
 283         $line = $body_ary[$i];
 284         if (strlen($line) - 2 >= $wrap_at) {
 285             sqWordWrap($line, $wrap_at);
 286         }
 287         $line = charset_decode($charset, $line);
 288         $line = str_replace("\t", '        ', $line);
 289
 290         parseUrl ($line);
 291
 292         $Quotes = 0;
 293         $pos = 0;
 294         $j = strlen( $line );
 295
 296         while ( $pos < $j ) {
 297             if ($line[$pos] == ' ') {
 298                 $pos ++;
 299             } else if (strpos($line, '&gt;', $pos) === $pos) {
 300                 $pos += 4;
 301                 $Quotes ++;
 302             } else {
 303                 break;
 304             }
 305         }
 306
 307         if ($Quotes > 1) {
 308             if (! isset($color[14])) {
 309                 $color[14] = '#FF0000';
 310             }
 311             $line = '<FONT COLOR="' . $color[14] . '">' . $line . '</FONT>';
 312         } elseif ($Quotes) {
 313             if (! isset($color[13])) {
 314                 $color[13] = '#800000';
 315             }
 316             $line = '<FONT COLOR="' . $color[13] . '">' . $line . '</FONT>';
 317         }
 318
 319         $body_ary[$i] = $line;
 320     }
 321     $body = '<pre>' . implode("\n", $body_ary) . '</pre>';
 322 }
 323
 324
 325 /* This returns a parsed string called $body. That string can then
 326 be displayed as the actual message in the HTML. It contains
 327 everything needed, including HTML Tags, Attachments at the
 328 bottom, etc.
 329 */
 330 function formatBody($imap_stream, $message, $color, $wrap_at, $ent_num, $id, $mailbox='INBOX') {
 331     // this if statement checks for the entity to show as the
 332     // primary message. To add more of them, just put them in the
 333     // order that is their priority.
 334     global $startMessage, $username, $key, $imapServerAddress, $imapPort,
 335            $show_html_default, $has_unsafe_images, $view_unsafe_images, $sort;
 336
 337     $has_unsafe_images= 0;
 338     $body = '';
 339     $urlmailbox = urlencode($mailbox);
 340     $body_message = getEntity($message, $ent_num);
 341     if (($body_message->header->type0 == 'text') ||
 342         ($body_message->header->type0 == 'rfc822')) {
 343         $body = mime_fetch_body ($imap_stream, $id, $ent_num);
 344         $body = decodeBody($body, $body_message->header->encoding);
 345         $hookResults = do_hook("message_body", $body);
 346         $body = $hookResults[1];
 347
 348         // If there are other types that shouldn't be formatted, add
 349         // them here
 350         if ($body_message->header->type1 == 'html') {
 351             if ( $show_html_default <> 1 ) {
 352                 $entity_conv = array('&nbsp;' => ' ',
 353                                      '&gt;'   => '>',
 354                                      '&lt;'   => '<');
 355                 $body = strip_tags( $body );
 356                 $body = strtr($body, $entity_conv);
 357                 $body = trim($body);
 358                 translateText($body, $wrap_at,
 359                               $body_message->header->getParameter['charset']);
 360             } else {
 361                 $body = magicHTML( $body, $id, $message, $mailbox );
 362             }
 363         } else {
 364             translateText($body, $wrap_at,
 365                $body_message->header->getParameter('charset'));
 366         }
 367
 368         if ($has_unsafe_images) {
 369             if ($view_unsafe_images) {
 370                 $body .= "<CENTER><SMALL><A HREF=\"read_body.php?passed_id=$id&amp;passed_ent_id=".$message->entity_id."&amp;mailbox=$urlmailbox&amp;sort=$sort&amp;startMessage=$startMessage&amp;show_more=0\">". _("Hide Unsafe Images") ."</A></SMALL></CENTER><BR>\n";
 371             } else {
 372                 $body .= "<CENTER><SMALL><A HREF=\"read_body.php?passed_id=$id&amp;passed_ent_id=".$message->entity_id."&amp;mailbox=$urlmailbox&amp;sort=$sort&amp;startMessage=$startMessage&amp;show_more=0&amp;view_unsafe_images=1\">". _("View Unsafe Images") ."</A></SMALL></CENTER><BR>\n";
 373             }
 374         }
 375     }
 376     return ($body);
 377 }
 378
 379
 380 function formatAttachments($message, $exclude_id, $mailbox, $id) {
 381     global $where, $what;
 382     global $startMessage, $color;
 383     static $ShownHTML = 0;
 384
 385     $att_ar = $message->getAttachments($exclude_id);
 386
 387     if (!count($att_ar)) return '';
 388
 389     $attachments = '';
 390
 391     $urlMailbox = urlencode($mailbox);
 392
 393     foreach ($att_ar as $att) {
 394         $ent = urldecode($att->entity_id);
 395         $header = $att->header;
 396         $type0 = strtolower($header->type0);
 397         $type1 = strtolower($header->type1);
 398         $name = '';
 399         $Links['download link']['text'] = _("download");
 400         $Links['download link']['href'] =
 401                 "../src/download.php?absolute_dl=true&amp;passed_id=$id&amp;mailbox=$urlMailbox&amp;ent_id=$ent";
 402         $ImageURL = '';
 403         if ($type0 =='message' && $type1 == 'rfc822') {
 404             $default_page = '../src/read_body.php';
 405             $rfc822_header = $att->rfc822_header;
 406             $filename = decodeHeader($rfc822_header->subject);
 407
 408             $from_o = $rfc822_header->from;
 409             if (is_object($from_o)) {
 410                 $from_name = $from_o->getAddress(false);
 411             } else {
 412                 $from_name = _("Unknown sender");
 413             }
 414             $from_name = decodeHeader(htmlspecialchars($from_name));
 415             $description = $from_name;
 416         } else {
 417             $default_page = '../src/download.php';
 418             if (is_object($header->disposition)) {
 419                $filename = decodeHeader($header->disposition->getProperty('filename'));
 420                if (trim($filename) == '') {
 421                   $name = decodeHeader($header->disposition->getProperty('name'));
 422                   if (trim($name) == '') {
 423                      if ( trim( $header->id ) == '' )
 424                         $filename = 'untitled-[' . $ent . ']' ;
 425                      else
 426                         $filename = 'cid: ' . $header->id;
 427                   } else {
 428                      $filename = $name;
 429                   }
 430                }
 431             } else {
 432                if ( trim( $header->id ) == '' )
 433                   $filename = 'untitled-[' . $ent . ']' ;
 434                else
 435                   $filename = 'cid: ' . $header->id;
 436             }
 437
 438             if ($header->description) {
 439                 $description = htmlspecialchars($header->description);
 440             } else {
 441                 $description = '';
 442             }
 443         }
 444
 445         $display_filename = $filename;
 446         if (isset($passed_ent_id)) {
 447            $passed_ent_id_link = '&amp;passed_ent_id='.$passed_ent_id;
 448         } else {
 449            $passed_ent_id_link = '';
 450         }
 451         $DefaultLink = $default_page . "?startMessage=$startMessage"
 452                      . "&amp;passed_id=$id&amp;mailbox=$urlMailbox"
 453                      . '&amp;ent_id='.$ent.$passed_ent_id_link;
 454         if ($where && $what) {
 455            $DefaultLink = '&amp;where='. urlencode($where).'&amp;what='.urlencode($what);
 456         }
 457         /* this executes the attachment hook with a specific MIME-type.
 458             * if that doens't have results, it tries if there's a rule
 459             * for a more generic type. */
 460         $HookResults = do_hook("attachment $type0/$type1", $Links,
 461             $startMessage, $id, $urlMailbox, $ent, $DefaultLink,
 462             $display_filename, $where, $what);
 463         if(count($HookResults[1]) <= 1) {
 464             $HookResults = do_hook("attachment $type0/*", $Links,
 465                     $startMessage, $id, $urlMailbox, $ent, $DefaultLink,
 466                     $display_filename, $where, $what);
 467         }
 468
 469         $Links = $HookResults[1];
 470         $DefaultLink = $HookResults[6];
 471
 472         $attachments .= '<TR><TD>' .
 473                         "<A HREF=\"$DefaultLink\">$display_filename</A>&nbsp;</TD>" .
 474                         '<TD><SMALL><b>' . show_readable_size($header->size) .
 475                         '</b>&nbsp;&nbsp;</small></TD>' .
 476                         "<TD><SMALL>[ $type0/$type1 ]&nbsp;</SMALL></TD>" .
 477                         '<TD><SMALL>';
 478         $attachments .= '<b>' . $description . '</b>';
 479         $attachments .= '</SMALL></TD><TD><SMALL>&nbsp;';
 480
 481         $SkipSpaces = 1;
 482         foreach ($Links as $Val) {
 483             if ($SkipSpaces) {
 484                 $SkipSpaces = 0;
 485             } else {
 486                 $attachments .= '&nbsp;&nbsp;|&nbsp;&nbsp;';
 487             }
 488             $attachments .= '<a href="' . $Val['href'] . '">' .  $Val['text'] . '</a>';
 489         }
 490         unset($Links);
 491         $attachments .= "</TD></TR>\n";
 492     }
 493     return $attachments;
 494 }
 495
 496 /** this function decodes the body depending on the encoding type. **/
 497 function decodeBody($body, $encoding) {
 498     global $languages, $squirrelmail_language;
 499
 500   $body = str_replace("\r\n", "\n", $body);
 501   $encoding = strtolower($encoding);
 502
 503   global $show_html_default;
 504
 505   if ($encoding == 'quoted-printable' ||
 506       $encoding == 'quoted_printable') {
 507      $body = quoted_printable_decode($body);
 508
 509      while (ereg("=\n", $body))
 510         $body = ereg_replace ("=\n", "", $body);
 511
 512   } else if ($encoding == 'base64') {
 513      $body = base64_decode($body);
 514   }
 515
 516   if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 517       function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
 518       $body = $languages[$squirrelmail_language]['XTRA_CODE']('decode', $body);
 519   }
 520
 521   // All other encodings are returned raw.
 522   return $body;
 523 }
 524
 525 /*
 526  * This functions decode strings that is encoded according to
 527  * RFC1522 (MIME Part Two: Message Header Extensions for Non-ASCII Text).
 528  * Patched by Christian Schmidt <christian@ostenfeld.dk>  23/03/2002
 529  */
 530 function decodeHeader ($string, $utfencode=true) {
 531     global $languages, $squirrelmail_language;
 532     if (is_array($string)) {
 533         $string = implode("\n", $string);
 534     }
 535
 536     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 537         function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
 538         $string = $languages[$squirrelmail_language]['XTRA_CODE']('decodeheader', $string);
 539     }
 540
 541     $i = 0;
 542     while (preg_match('/^(.{' . $i . '})(.*)=\?([^?]*)\?(Q|B)\?([^?]*)\?=/Ui',
 543                       $string, $res)) {
 544         $prefix = $res[1];
 545         // Ignore white-space between consecutive encoded-words
 546         if (strspn($res[2], " \t") != strlen($res[2])) {
 547             $prefix .= $res[2];
 548         }
 549
 550         if (ucfirst($res[4]) == 'B') {
 551             $replace = base64_decode($res[5]);
 552         } else {
 553             $replace = str_replace('_', ' ', $res[5]);
 554             $replace = preg_replace('/=([0-9a-f]{2})/ie', 'chr(hexdec("\1"))',
 555                                     $replace);
 556             /* Only encode into entities by default. Some places
 557                don't need the encoding, like the compose form. */
 558             if ($utfencode) {
 559                 $replace = charset_decode($res[3], $replace);
 560             }
 561         }
 562         $string = $prefix . $replace . substr($string, strlen($res[0]));
 563         $i = strlen($prefix) + strlen($replace);
 564     }
 565     return( $string );
 566 }
 567
 568 /*
 569  * Encode a string according to RFC 1522 for use in headers if it
 570  * contains 8-bit characters or anything that looks like it should
 571  * be encoded.
 572  */
 573 function encodeHeader ($string) {
 574     global $default_charset, $languages, $squirrelmail_language;
 575
 576     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 577         function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
 578         return  $languages[$squirrelmail_language]['XTRA_CODE']('encodeheader', $string);
 579     }
 580
 581     // Encode only if the string contains 8-bit characters or =?
 582     $j = strlen( $string  );
 583     $l = strstr($string, '=?');         // Must be encoded ?
 584     $ret = '';
 585     for( $i=0; $i < $j; ++$i) {
 586         switch( $string{$i} ) {
 587            case '=':
 588           $ret .= '=3D';
 589           break;
 590         case '?':
 591           $ret .= '=3F';
 592           break;
 593         case '_':
 594           $ret .= '=5F';
 595           break;
 596         case ' ':
 597           $ret .= '_';
 598           break;
 599         default:
 600           $k = ord( $string{$i} );
 601           if ( $k > 126 ) {
 602              $ret .= sprintf("=%02X", $k);
 603              $l = TRUE;
 604           } else
 605              $ret .= $string{$i};
 606         }
 607     }
 608
 609     if ( $l ) {
 610         $string = "=?$default_charset?Q?$ret?=";
 611     }
 612
 613     return( $string );
 614 }
 615
 616 /* This function trys to locate the entity_id of a specific mime element */
 617
 618 function find_ent_id( $id, $message ) {
 619     $ret = '';
 620     for ($i=0; $ret == '' && $i < count($message->entities); $i++) {
 621         if ( $message->entities[$i]->header->type0 == 'multipart')  {
 622             $ret = find_ent_id( $id, $message->entities[$i] );
 623         } else {
 624             if ( strcasecmp( $message->entities[$i]->header->id, $id ) == 0 )
 625                 $ret = $message->entities[$i]->entity_id;
 626         }
 627     }
 628     return( $ret );
 629 }
 630
 631 /**
 632  ** HTMLFILTER ROUTINES
 633  */
 634
 635 /**
 636  * This function returns the final tag out of the tag name, an array
 637  * of attributes, and the type of the tag. This function is called by
 638  * sq_sanitize internally.
 639  *
 640  * @param  $tagname  the name of the tag.
 641  * @param  $attary   the array of attributes and their values
 642  * @param  $tagtype  The type of the tag (see in comments).
 643  * @return           a string with the final tag representation.
 644  */
 645 function sq_tagprint($tagname, $attary, $tagtype){
 646     $me = "sq_tagprint";
 647     if ($tagtype == 2){
 648         $fulltag = '</' . $tagname . '>';
 649     } else {
 650         $fulltag = '<' . $tagname;
 651         if (is_array($attary) && sizeof($attary)){
 652             $atts = Array();
 653             while (list($attname, $attvalue) = each($attary)){
 654                 array_push($atts, "$attname=$attvalue");
 655             }
 656             $fulltag .= ' ' . join(" ", $atts);
 657         }
 658         if ($tagtype == 3){
 659             $fulltag .= " /";
 660         }
 661         $fulltag .= ">";
 662     }
 663     return $fulltag;
 664 }
 665
 666 /**
 667  * A small helper function to use with array_walk. Modifies a by-ref
 668  * value and makes it lowercase.
 669  *
 670  * @param  $val a value passed by-ref.
 671  * @return      void since it modifies a by-ref value.
 672  */
 673 function sq_casenormalize(&$val){
 674     $val = strtolower($val);
 675 }
 676
 677 /**
 678  * This function skips any whitespace from the current position within
 679  * a string and to the next non-whitespace value.
 680  *
 681  * @param  $body   the string
 682  * @param  $offset the offset within the string where we should start
 683  *                 looking for the next non-whitespace character.
 684  * @return         the location within the $body where the next
 685  *                 non-whitespace char is located.
 686  */
 687 function sq_skipspace($body, $offset){
 688     $me = "sq_skipspace";
 689     preg_match("/^(\s*)/s", substr($body, $offset), $matches);
 690     if (sizeof($matches{1})){
 691         $count = strlen($matches{1});
 692         $offset += $count;
 693     }
 694     return $offset;
 695 }
 696
 697 /**
 698  * This function looks for the next character within a string.  It's
 699  * really just a glorified "strpos", except it catches if failures
 700  * nicely.
 701  *
 702  * @param  $body   The string to look for needle in.
 703  * @param  $offset Start looking from this position.
 704  * @param  $needle The character/string to look for.
 705  * @return         location of the next occurance of the needle, or
 706  *                 strlen($body) if needle wasn't found.
 707  */
 708 function sq_findnxstr($body, $offset, $needle){
 709     $me = "sq_findnxstr";
 710     $pos = strpos($body, $needle, $offset);
 711     if ($pos === FALSE){
 712         $pos = strlen($body);
 713     }
 714     return $pos;
 715 }
 716
 717 /**
 718  * This function takes a PCRE-style regexp and tries to match it
 719  * within the string.
 720  *
 721  * @param  $body   The string to look for needle in.
 722  * @param  $offset Start looking from here.
 723  * @param  $reg    A PCRE-style regex to match.
 724  * @return         Returns a false if no matches found, or an array
 725  *                 with the following members:
 726  *                 - integer with the location of the match within $body
 727  *                 - string with whatever content between offset and the match
 728  *                 - string with whatever it is we matched
 729  */
 730 function sq_findnxreg($body, $offset, $reg){
 731     $me = "sq_findnxreg";
 732     $matches = Array();
 733     $retarr = Array();
 734     preg_match("%^(.*?)($reg)%s", substr($body, $offset), $matches);
 735     if (!$matches{0}){
 736         $retarr = false;
 737     } else {
 738         $retarr{0} = $offset + strlen($matches{1});
 739         $retarr{1} = $matches{1};
 740         $retarr{2} = $matches{2};
 741     }
 742     return $retarr;
 743 }
 744
 745 /**
 746  * This function looks for the next tag.
 747  *
 748  * @param  $body   String where to look for the next tag.
 749  * @param  $offset Start looking from here.
 750  * @return         false if no more tags exist in the body, or
 751  *                 an array with the following members:
 752  *                 - string with the name of the tag
 753  *                 - array with attributes and their values
 754  *                 - integer with tag type (1, 2, or 3)
 755  *                 - integer where the tag starts (starting "<")
 756  *                 - integer where the tag ends (ending ">")
 757  *                 first three members will be false, if the tag is invalid.
 758  */
 759 function sq_getnxtag($body, $offset){
 760     $me = "sq_getnxtag";
 761     if ($offset > strlen($body)){
 762         return false;
 763     }
 764     $lt = sq_findnxstr($body, $offset, "<");
 765     if ($lt == strlen($body)){
 766         return false;
 767     }
 768     /**
 769      * We are here:
 770      * blah blah <tag attribute="value">
 771      * \---------^
 772      */
 773     $pos = sq_skipspace($body, $lt+1);
 774     if ($pos >= strlen($body)){
 775         return Array(false, false, false, $lt, strlen($body));
 776     }
 777     /**
 778      * There are 3 kinds of tags:
 779      * 1. Opening tag, e.g.:
 780      *    <a href="blah">
 781      * 2. Closing tag, e.g.:
 782      *    </a>
 783      * 3. XHTML-style content-less tag, e.g.:
 784      *    <img src="blah"/>
 785      */
 786     $tagtype = false;
 787     switch (substr($body, $pos, 1)){
 788     case "/":
 789         $tagtype = 2;
 790         $pos++;
 791         break;
 792     case "!":
 793         /**
 794          * A comment or an SGML declaration.
 795          */
 796         if (substr($body, $pos+1, 2) == "--"){
 797             $gt = strpos($body, "-->", $pos);
 798             if ($gt === false){
 799                 $gt = strlen($body);
 800             } else {
 801                 $gt += 2;
 802             }
 803             return Array(false, false, false, $lt, $gt);
 804         } else {
 805             $gt = sq_findnxstr($body, $pos, ">");
 806             return Array(false, false, false, $lt, $gt);
 807         }
 808         break;
 809     default:
 810         /**
 811          * Assume tagtype 1 for now. If it's type 3, we'll switch values
 812          * later.
 813          */
 814         $tagtype = 1;
 815         break;
 816     }
 817
 818     $tag_start = $pos;
 819     $tagname = '';
 820     /**
 821      * Look for next [\W-_], which will indicate the end of the tag name.
 822      */
 823     $regary = sq_findnxreg($body, $pos, "[^\w\-_]");
 824     if ($regary == false){
 825         return Array(false, false, false, $lt, strlen($body));
 826     }
 827     list($pos, $tagname, $match) = $regary;
 828     $tagname = strtolower($tagname);
 829
 830     /**
 831      * $match can be either of these:
 832      * '>'  indicating the end of the tag entirely.
 833      * '\s' indicating the end of the tag name.
 834      * '/'  indicating that this is type-3 xhtml tag.
 835      *
 836      * Whatever else we find there indicates an invalid tag.
 837      */
 838     switch ($match){
 839     case "/":
 840         /**
 841          * This is an xhtml-style tag with a closing / at the
 842          * end, like so: <img src="blah"/>. Check if it's followed
 843          * by the closing bracket. If not, then this tag is invalid
 844          */
 845         if (substr($body, $pos, 2) == "/>"){
 846             $pos++;
 847             $tagtype = 3;
 848         } else {
 849             $gt = sq_findnxstr($body, $pos, ">");
 850             $retary = Array(false, false, false, $lt, $gt);
 851             return $retary;
 852         }
 853     case ">":
 854         return Array($tagname, false, $tagtype, $lt, $pos);
 855         break;
 856     default:
 857         /**
 858          * Check if it's whitespace
 859          */
 860         if (preg_match("/\s/", $match)){
 861         } else {
 862             /**
 863              * This is an invalid tag! Look for the next closing ">".
 864              */
 865             $gt = sq_findnxstr($body, $offset, ">");
 866             return Array(false, false, false, $lt, $gt);
 867         }
 868     }
 869
 870     /**
 871      * At this point we're here:
 872      * <tagname  attribute='blah'>
 873      * \-------^
 874      *
 875      * At this point we loop in order to find all attributes.
 876      */
 877     $attname = '';
 878     $atttype = false;
 879     $attary = Array();
 880
 881     while ($pos <= strlen($body)){
 882         $pos = sq_skipspace($body, $pos);
 883         if ($pos == strlen($body)){
 884             /**
 885              * Non-closed tag.
 886              */
 887             return Array(false, false, false, $lt, $pos);
 888         }
 889         /**
 890          * See if we arrived at a ">" or "/>", which means that we reached
 891          * the end of the tag.
 892          */
 893         $matches = Array();
 894         if (preg_match("%^(\s*)(>|/>)%s", substr($body, $pos), $matches)) {
 895             /**
 896              * Yep. So we did.
 897              */
 898             $pos += strlen($matches{1});
 899             if ($matches{2} == "/>"){
 900                 $tagtype = 3;
 901                 $pos++;
 902             }
 903             return Array($tagname, $attary, $tagtype, $lt, $pos);
 904         }
 905
 906         /**
 907          * There are several types of attributes, with optional
 908          * [:space:] between members.
 909          * Type 1:
 910          *   attrname[:space:]=[:space:]'CDATA'
 911          * Type 2:
 912          *   attrname[:space:]=[:space:]"CDATA"
 913          * Type 3:
 914          *   attr[:space:]=[:space:]CDATA
 915          * Type 4:
 916          *   attrname
 917          *
 918          * We leave types 1 and 2 the same, type 3 we check for
 919          * '"' and convert to "&quot" if needed, then wrap in
 920          * double quotes. Type 4 we convert into:
 921          * attrname="yes".
 922          */
 923         $regary = sq_findnxreg($body, $pos, "[^\w\-_]");
 924         if ($regary == false){
 925             /**
 926              * Looks like body ended before the end of tag.
 927              */
 928             return Array(false, false, false, $lt, strlen($body));
 929         }
 930         list($pos, $attname, $match) = $regary;
 931         $attname = strtolower($attname);
 932         /**
 933          * We arrived at the end of attribute name. Several things possible
 934          * here:
 935          * '>'  means the end of the tag and this is attribute type 4
 936          * '/'  if followed by '>' means the same thing as above
 937          * '\s' means a lot of things -- look what it's followed by.
 938          *      anything else means the attribute is invalid.
 939          */
 940         switch($match){
 941         case "/":
 942             /**
 943              * This is an xhtml-style tag with a closing / at the
 944              * end, like so: <img src="blah"/>. Check if it's followed
 945              * by the closing bracket. If not, then this tag is invalid
 946              */
 947             if (substr($body, $pos, 2) == "/>"){
 948                 $pos++;
 949                 $tagtype = 3;
 950             } else {
 951                 $gt = sq_findnxstr($body, $pos, ">");
 952                 $retary = Array(false, false, false, $lt, $gt);
 953                 return $retary;
 954             }
 955         case ">":
 956             $attary{$attname} = '"yes"';
 957             return Array($tagname, $attary, $tagtype, $lt, $pos);
 958             break;
 959         default:
 960             /**
 961              * Skip whitespace and see what we arrive at.
 962              */
 963             $pos = sq_skipspace($body, $pos);
 964             $char = substr($body, $pos, 1);
 965             /**
 966              * Two things are valid here:
 967              * '=' means this is attribute type 1 2 or 3.
 968              * \w means this was attribute type 4.
 969              * anything else we ignore and re-loop. End of tag and
 970              * invalid stuff will be caught by our checks at the beginning
 971              * of the loop.
 972              */
 973             if ($char == "="){
 974                 $pos++;
 975                 $pos = sq_skipspace($body, $pos);
 976                 /**
 977                  * Here are 3 possibilities:
 978                  * "'"  attribute type 1
 979                  * '"'  attribute type 2
 980                  * everything else is the content of tag type 3
 981                  */
 982                 $quot = substr($body, $pos, 1);
 983                 if ($quot == "'"){
 984                     $regary = sq_findnxreg($body, $pos+1, "\'");
 985                     if ($regary == false){
 986                         return Array(false, false, false, $lt, strlen($body));
 987                     }
 988                     list($pos, $attval, $match) = $regary;
 989                     $pos++;
 990                     $attary{$attname} = "'" . $attval . "'";
 991                 } else if ($quot == '"'){
 992                     $regary = sq_findnxreg($body, $pos+1, '\"');
 993                     if ($regary == false){
 994                         return Array(false, false, false, $lt, strlen($body));
 995                     }
 996                     list($pos, $attval, $match) = $regary;
 997                     $pos++;
 998                     $attary{$attname} = '"' . $attval . '"';
 999                 } else {
1000                     /**
1001                      * These are hateful. Look for \s, or >.
1002                      */
1003                     $regary = sq_findnxreg($body, $pos, "[\s>]");
1004                     if ($regary == false){
1005                         return Array(false, false, false, $lt, strlen($body));
1006                     }
1007                     list($pos, $attval, $match) = $regary;
1008                     /**
1009                      * If it's ">" it will be caught at the top.
1010                      */
1011                     $attval = preg_replace("/\"/s", "&quot;", $attval);
1012                     $attary{$attname} = '"' . $attval . '"';
1013                 }
1014             } else if (preg_match("|[\w/>]|", $char)) {
1015                 /**
1016                  * That was attribute type 4.
1017                  */
1018                 $attary{$attname} = '"yes"';
1019             } else {
1020                 /**
1021                  * An illegal character. Find next '>' and return.
1022                  */
1023                 $gt = sq_findnxstr($body, $pos, ">");
1024                 return Array(false, false, false, $lt, $gt);
1025             }
1026         }
1027     }
1028     /**
1029      * The fact that we got here indicates that the tag end was never
1030      * found. Return invalid tag indication so it gets stripped.
1031      */
1032     return Array(false, false, false, $lt, strlen($body));
1033 }
1034
1035 /**
1036  * This function checks attribute values for entity-encoded values
1037  * and returns them translated into 8-bit strings so we can run
1038  * checks on them.
1039  *
1040  * @param  $attvalue A string to run entity check against.
1041  * @return           Translated value.
1042  */
1043 function sq_deent($attvalue){
1044     $me="sq_deent";
1045     /**
1046      * See if we have to run the checks first. All entities must start
1047      * with "&".
1048      */
1049     if (strpos($attvalue, "&") === false){
1050         return $attvalue;
1051     }
1052     /**
1053      * Check named entities first.
1054      */
1055     $trans = get_html_translation_table(HTML_ENTITIES);
1056     /**
1057      * Leave &quot; in, as it can mess us up.
1058      */
1059     $trans = array_flip($trans);
1060     unset($trans{"&quot;"});
1061     while (list($ent, $val) = each($trans)){
1062         $attvalue = preg_replace("/$ent*(\W)/si", "$val\\1", $attvalue);
1063     }
1064     /**
1065      * Now translate numbered entities from 1 to 255 if needed.
1066      */
1067     if (strpos($attvalue, "#") !== false){
1068         $omit = Array(34, 39);
1069         for ($asc=1; $asc<256; $asc++){
1070             if (!in_array($asc, $omit)){
1071                 $chr = chr($asc);
1072                 $attvalue = preg_replace("/\&#0*$asc;*(\D)/si", "$chr\\1",
1073                                          $attvalue);
1074                 $attvalue = preg_replace("/\&#x0*".dechex($asc).";*(\W)/si",
1075                                          "$chr\\1", $attvalue);
1076             }
1077         }
1078     }
1079     return $attvalue;
1080 }
1081
1082 /**
1083  * This function runs various checks against the attributes.
1084  *
1085  * @param  $tagname         String with the name of the tag.
1086  * @param  $attary          Array with all tag attributes.
1087  * @param  $rm_attnames     See description for sq_sanitize
1088  * @param  $bad_attvals     See description for sq_sanitize
1089  * @param  $add_attr_to_tag See description for sq_sanitize
1090  * @param  $message         message object
1091  * @param  $id              message id
1092  * @return                  Array with modified attributes.
1093  */
1094 function sq_fixatts($tagname,
1095                     $attary,
1096                     $rm_attnames,
1097                     $bad_attvals,
1098                     $add_attr_to_tag,
1099                     $message,
1100                     $id,
1101                     $mailbox
1102                     ){
1103     $me = "sq_fixatts";
1104     while (list($attname, $attvalue) = each($attary)){
1105         /**
1106          * See if this attribute should be removed.
1107          */
1108         foreach ($rm_attnames as $matchtag=>$matchattrs){
1109             if (preg_match($matchtag, $tagname)){
1110                 foreach ($matchattrs as $matchattr){
1111                     if (preg_match($matchattr, $attname)){
1112                         unset($attary{$attname});
1113                         continue;
1114                     }
1115                 }
1116             }
1117         }
1118         /**
1119          * Remove any entities.
1120          */
1121         $attvalue = sq_deent($attvalue);
1122
1123         /**
1124          * Now let's run checks on the attvalues.
1125          * I don't expect anyone to comprehend this. If you do,
1126          * get in touch with me so I can drive to where you live and
1127          * shake your hand personally. :)
1128          */
1129         foreach ($bad_attvals as $matchtag=>$matchattrs){
1130             if (preg_match($matchtag, $tagname)){
1131                 foreach ($matchattrs as $matchattr=>$valary){
1132                     if (preg_match($matchattr, $attname)){
1133                         /**
1134                          * There are two arrays in valary.
1135                          * First is matches.
1136                          * Second one is replacements
1137                          */
1138                         list($valmatch, $valrepl) = $valary;
1139                         $newvalue =
1140                             preg_replace($valmatch, $valrepl, $attvalue);
1141                         if ($newvalue != $attvalue){
1142                             $attary{$attname} = $newvalue;
1143                         }
1144                     }
1145                 }
1146             }
1147         }
1148         /**
1149          * Turn cid: urls into http-friendly ones.
1150          */
1151         if (preg_match("/^[\'\"]\s*cid:/si", $attvalue)){
1152             $attary{$attname} = sq_cid2http($message, $id, $attvalue, $mailbox);
1153         }
1154     }
1155     /**
1156      * See if we need to append any attributes to this tag.
1157      */
1158     foreach ($add_attr_to_tag as $matchtag=>$addattary){
1159         if (preg_match($matchtag, $tagname)){
1160             $attary = array_merge($attary, $addattary);
1161         }
1162     }
1163     return $attary;
1164 }
1165
1166 /**
1167  * This function edits the style definition to make them friendly and
1168  * usable in squirrelmail.
1169  *
1170  * @param  $message  the message object
1171  * @param  $id       the message id
1172  * @param  $content  a string with whatever is between <style> and </style>
1173  * @return           a string with edited content.
1174  */
1175 function sq_fixstyle($message, $id, $content){
1176     global $view_unsafe_images;
1177     $me = "sq_fixstyle";
1178     /**
1179      * First look for general BODY style declaration, which would be
1180      * like so:
1181      * body {background: blah-blah}
1182      * and change it to .bodyclass so we can just assign it to a <div>
1183      */
1184     $content = preg_replace("|body(\s*\{.*?\})|si", ".bodyclass\\1", $content);
1185     $secremoveimg = "../images/" . _("sec_remove_eng.png");
1186     /**
1187      * Fix url('blah') declarations.
1188      */
1189     $content = preg_replace("|url\(([\'\"])\s*\S+script\s*:.*?([\'\"])\)|si",
1190                             "url(\\1$secremoveimg\\2)", $content);
1191     /**
1192      * Fix url('https*://.*) declarations but only if $view_unsafe_images
1193      * is false.
1194      */
1195     if (!$view_unsafe_images){
1196         $content = preg_replace("|url\(([\'\"])\s*https*:.*?([\'\"])\)|si",
1197                                 "url(\\1$secremoveimg\\2)", $content);
1198     }
1199
1200     /**
1201      * Fix urls that refer to cid:
1202      */
1203     while (preg_match("|url\(([\'\"]\s*cid:.*?[\'\"])\)|si", $content,
1204                       $matches)){
1205         $cidurl = $matches{1};
1206         $httpurl = sq_cid2http($message, $id, $cidurl);
1207         $content = preg_replace("|url\($cidurl\)|si",
1208                                 "url($httpurl)", $content);
1209     }
1210
1211     /**
1212      * Fix stupid css declarations which lead to vulnerabilities
1213      * in IE.
1214      */
1215     $match   = Array('/expression/si',
1216                      '/behaviou*r/si',
1217                      '/binding/si');
1218     $replace = Array('idiocy', 'idiocy', 'idiocy');
1219     $content = preg_replace($match, $replace, $content);
1220     return $content;
1221 }
1222
1223 /**
1224  * This function converts cid: url's into the ones that can be viewed in
1225  * the browser.
1226  *
1227  * @param  $message  the message object
1228  * @param  $id       the message id
1229  * @param  $cidurl   the cid: url.
1230  * @return           a string with a http-friendly url
1231  */
1232 function sq_cid2http($message, $id, $cidurl, $mailbox){
1233     /**
1234      * Get rid of quotes.
1235      */
1236     $quotchar = substr($cidurl, 0, 1);
1237     $cidurl = str_replace($quotchar, "", $cidurl);
1238     $cidurl = substr(trim($cidurl), 4);
1239     $httpurl = $quotchar . "../src/download.php?absolute_dl=true&amp;" .
1240         "passed_id=$id&amp;mailbox=" . urlencode($mailbox) .
1241         "&amp;ent_id=" . find_ent_id($cidurl, $message) . $quotchar;
1242     return $httpurl;
1243 }
1244
1245 /**
1246  * This function changes the <body> tag into a <div> tag since we
1247  * can't really have a body-within-body.
1248  *
1249  * @param  $attary  an array of attributes and values of <body>
1250  * @return          a modified array of attributes to be set for <div>
1251  */
1252 function sq_body2div($attary){
1253     $me = "sq_body2div";
1254     $divattary = Array("class"=>"'bodyclass'");
1255     $bgcolor="#ffffff";
1256     $text="#000000";
1257     $styledef="";
1258     if (is_array($attary) && sizeof($attary) > 0){
1259         foreach ($attary as $attname=>$attvalue){
1260             $quotchar = substr($attvalue, 0, 1);
1261             $attvalue = str_replace($quotchar, "", $attvalue);
1262             switch ($attname){
1263             case "background":
1264                 $styledef .= "background-image: url('$attvalue'); ";
1265                 break;
1266             case "bgcolor":
1267                 $styledef .= "background-color: $attvalue; ";
1268                 break;
1269             case "text":
1270                 $styledef .= "color: $attvalue; ";
1271             }
1272         }
1273         if (strlen($styledef) > 0){
1274             $divattary{"style"} = "\"$styledef\"";
1275         }
1276     }
1277     return $divattary;
1278 }
1279
1280 /**
1281  * This is the main function and the one you should actually be calling.
1282  * There are several variables you should be aware of an which need
1283  * special description.
1284  *
1285  * Since the description is quite lengthy, see it here:
1286  * http://www.mricon.com/html/phpfilter.html
1287  *
1288  * @param $body                 the string with HTML you wish to filter
1289  * @param $tag_list             see description above
1290  * @param $rm_tags_with_content see description above
1291  * @param $self_closing_tags    see description above
1292  * @param $force_tag_closing    see description above
1293  * @param $rm_attnames          see description above
1294  * @param $bad_attvals          see description above
1295  * @param $add_attr_to_tag      see description above
1296  * @param $message              message object
1297  * @param $id                   message id
1298  * @return                      sanitized html safe to show on your pages.
1299  */
1300 function sq_sanitize($body,
1301                      $tag_list,
1302                      $rm_tags_with_content,
1303                      $self_closing_tags,
1304                      $force_tag_closing,
1305                      $rm_attnames,
1306                      $bad_attvals,
1307                      $add_attr_to_tag,
1308                      $message,
1309                      $id,
1310                      $mailbox
1311                      ){
1312     $me = "sq_sanitize";
1313     /**
1314      * Normalize rm_tags and rm_tags_with_content.
1315      */
1316     @array_walk($rm_tags, 'sq_casenormalize');
1317     @array_walk($rm_tags_with_content, 'sq_casenormalize');
1318     @array_walk($self_closing_tags, 'sq_casenormalize');
1319     /**
1320      * See if tag_list is of tags to remove or tags to allow.
1321      * false  means remove these tags
1322      * true   means allow these tags
1323      */
1324     $rm_tags = array_shift($tag_list);
1325     $curpos = 0;
1326     $open_tags = Array();
1327     $trusted = "<!-- begin sanitized html -->\n";
1328     $skip_content = false;
1329     /**
1330      * Take care of netscape's stupid javascript entities like
1331      * &{alert('boo')};
1332      */
1333     $body = preg_replace("/&(\{.*?\};)/si", "&amp;\\1", $body);
1334
1335     while (($curtag=sq_getnxtag($body, $curpos)) != FALSE){
1336         list($tagname, $attary, $tagtype, $lt, $gt) = $curtag;
1337         $free_content = substr($body, $curpos, $lt-$curpos);
1338         /**
1339          * Take care of <style>
1340          */
1341         if ($tagname == "style" && $tagtype == 2){
1342             /**
1343              * This is a closing </style>. Edit the
1344              * content before we apply it.
1345              */
1346             $free_content = sq_fixstyle($message, $id, $free_content);
1347         }
1348         if ($skip_content == false){
1349             $trusted .= $free_content;
1350         } else {
1351         }
1352         if ($tagname != FALSE){
1353             if ($tagtype == 2){
1354                 if ($skip_content == $tagname){
1355                     /**
1356                      * Got to the end of tag we needed to remove.
1357                      */
1358                     $tagname = false;
1359                     $skip_content = false;
1360                 } else {
1361                     if ($skip_content == false){
1362                         if ($tagname == "body"){
1363                             $tagname = "div";
1364                         } else {
1365                             if (isset($open_tags{$tagname}) &&
1366                                 $open_tags{$tagname} > 0){
1367                                 $open_tags{$tagname}--;
1368                             } else {
1369                                 $tagname = false;
1370                             }
1371                         }
1372                     } else {
1373                     }
1374                 }
1375             } else {
1376                 /**
1377                  * $rm_tags_with_content
1378                  */
1379                 if ($skip_content == false){
1380                     /**
1381                      * See if this is a self-closing type and change
1382                      * tagtype appropriately.
1383                      */
1384                     if ($tagtype == 1
1385                         && in_array($tagname, $self_closing_tags)){
1386                         $tagtype=3;
1387                     }
1388                     /**
1389                      * See if we should skip this tag and any content
1390                      * inside it.
1391                      */
1392                     if ($tagtype == 1 &&
1393                         in_array($tagname, $rm_tags_with_content)){
1394                         $skip_content = $tagname;
1395                     } else {
1396                         if (($rm_tags == false
1397                              && in_array($tagname, $tag_list)) ||
1398                             ($rm_tags == true &&
1399                              !in_array($tagname, $tag_list))){
1400                             $tagname = false;
1401                         } else {
1402                             if ($tagtype == 1){
1403                                 if (isset($open_tags{$tagname})){
1404                                     $open_tags{$tagname}++;
1405                                 } else {
1406                                     $open_tags{$tagname}=1;
1407                                 }
1408                             }
1409                             /**
1410                              * This is where we run other checks.
1411                              */
1412                             if (is_array($attary) && sizeof($attary) > 0){
1413                                 $attary = sq_fixatts($tagname,
1414                                                      $attary,
1415                                                      $rm_attnames,
1416                                                      $bad_attvals,
1417                                                      $add_attr_to_tag,
1418                                                      $message,
1419                                                      $id,
1420                                                      $mailbox
1421                                                      );
1422                             }
1423                             /**
1424                              * Convert body into div.
1425                              */
1426                             if ($tagname == "body"){
1427                                 $tagname = "div";
1428                                 $attary = sq_body2div($attary, $message, $id);
1429                             }
1430                         }
1431                     }
1432                 } else {
1433                 }
1434             }
1435             if ($tagname != false && $skip_content == false){
1436                 $trusted .= sq_tagprint($tagname, $attary, $tagtype);
1437             }
1438         } else {
1439         }
1440         $curpos = $gt+1;
1441     }
1442     $trusted .= substr($body, $curpos, strlen($body)-$curpos);
1443     if ($force_tag_closing == true){
1444         foreach ($open_tags as $tagname=>$opentimes){
1445             while ($opentimes > 0){
1446                 $trusted .= '</' . $tagname . '>';
1447                 $opentimes--;
1448             }
1449         }
1450         $trusted .= "\n";
1451     }
1452     $trusted .= "<!-- end sanitized html -->\n";
1453     return $trusted;
1454 }
1455
1456 /**
1457  * This is a wrapper function to call html sanitizing routines.
1458  *
1459  * @param  $body  the body of the message
1460  * @param  $id    the id of the message
1461  * @return        a string with html safe to display in the browser.
1462  */
1463 function magicHTML($body, $id, $message, $mailbox = 'INBOX'){
1464     global $attachment_common_show_images, $view_unsafe_images,
1465         $has_unsafe_images;
1466     /**
1467      * Don't display attached images in HTML mode.
1468      */
1469     $attachment_common_show_images = false;
1470     $tag_list = Array(
1471                       false,
1472                       "object",
1473                       "meta",
1474                       "html",
1475                       "head",
1476                       "base",
1477                       "link"
1478                       );
1479
1480     $rm_tags_with_content = Array(
1481                                   "script",
1482                                   "applet",
1483                                   "embed",
1484                                   "title"
1485                                   );
1486
1487     $self_closing_tags =  Array(
1488                                 "img",
1489                                 "br",
1490                                 "hr",
1491                                 "input"
1492                                 );
1493
1494     $force_tag_closing = false;
1495
1496     $rm_attnames = Array(
1497                          "/.*/" =>
1498                          Array(
1499                                "/target/si",
1500                                "/^on.*/si",
1501                                "/^dynsrc/si",
1502                                "/^data.*/si"
1503                                )
1504                          );
1505
1506     $secremoveimg = "../images/" . _("sec_remove_eng.png");
1507     $bad_attvals = Array(
1508         "/.*/" =>
1509             Array(
1510                 "/^src|background/i" =>
1511                     Array(
1512                           Array(
1513                                 "|^([\'\"])\s*\.\./.*([\'\"])|si",
1514                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1515                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1516                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1517                                 ),
1518                           Array(
1519                                 "\\1$secremoveimg\\2",
1520                                 "\\1$secremoveimg\\2",
1521                                 "\\1$secremoveimg\\2",
1522                                 "\\1$secremoveimg\\2"
1523                                 )
1524                         ),
1525                 "/^href|action/i" =>
1526                     Array(
1527                           Array(
1528                                 "|^([\'\"])\s*\.\./.*([\'\"])|si",
1529                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1530                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1531                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1532                                 ),
1533                           Array(
1534                                 "\\1#\\2",
1535                                 "\\1#\\2",
1536                                 "\\1#\\2",
1537                                 "\\1#\\2"
1538                                 )
1539                         ),
1540                 "/^style/si" =>
1541                     Array(
1542                           Array(
1543                                 "/expression/si",
1544                                 "/binding/si",
1545                                 "/behaviou*r/si",
1546                                 "|url\(([\'\"])\s*\.\./.*([\'\"])\)|si",
1547                                 "/url\(([\'\"])\s*\S+script\s*:.*([\'\"])\)/si",
1548                                 "/url\(([\'\"])\s*mocha\s*:.*([\'\"])\)/si",
1549                                 "/url\(([\'\"])\s*about\s*:.*([\'\"])\)/si"
1550                                ),
1551                           Array(
1552                                 "idiocy",
1553                                 "idiocy",
1554                                 "idiocy",
1555                                 "url(\\1#\\2)",
1556                                 "url(\\1#\\2)",
1557                                 "url(\\1#\\2)",
1558                                 "url(\\1#\\2)"
1559                                )
1560                           )
1561                 )
1562         );
1563     if (!$view_unsafe_images){
1564         /**
1565          * Remove any references to http/https if view_unsafe_images set
1566          * to false.
1567          */
1568          array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[0],
1569                     '/^([\'\"])\s*https*:.*([\'\"])/si');
1570          array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[1],
1571                     "\\1$secremoveimg\\2");
1572          array_push($bad_attvals{'/.*/'}{'/^style/si'}[0],
1573                     '/url\(([\'\"])\s*https*:.*([\'\"])\)/si');
1574          array_push($bad_attvals{'/.*/'}{'/^style/si'}[1],
1575                     "url(\\1$secremoveimg\\2)");
1576     }
1577
1578     $add_attr_to_tag = Array(
1579                              "/^a$/si" => Array('target'=>'"_new"')
1580                              );
1581     $trusted = sq_sanitize($body,
1582                            $tag_list,
1583                            $rm_tags_with_content,
1584                            $self_closing_tags,
1585                            $force_tag_closing,
1586                            $rm_attnames,
1587                            $bad_attvals,
1588                            $add_attr_to_tag,
1589                            $message,
1590                            $id,
1591                            $mailbox
1592                            );
1593     if (preg_match("|$secremoveimg|si", $trusted)){
1594         $has_unsafe_images = true;
1595     }
1596     return $trusted;
1597 }
1598
1599 ?>