functions/mime.php

   1 <?php
   2
   3 /**
   4 * mime.php
   5 *
   6 * Copyright (c) 1999-2005 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 * @version $Id$
  13 * @package squirrelmail
  14 */
  15
  16 /** The typical includes... */
  17 require_once(SM_PATH . 'functions/imap.php');
  18 require_once(SM_PATH . 'functions/attachment_common.php');
  19 /** add sqm_baseuri()*/
  20 include_once(SM_PATH . 'functions/display_messages.php');
  21
  22 /* -------------------------------------------------------------------------- */
  23 /* MIME DECODING                                                              */
  24 /* -------------------------------------------------------------------------- */
  25
  26 /**
  27 * Get the MIME structure
  28 *
  29 * This function gets the structure of a message and stores it in the "message" class.
  30 * It will return this object for use with all relevant header information and
  31 * fully parsed into the standard "message" object format.
  32 */
  33 function mime_structure ($bodystructure, $flags=array()) {
  34
  35     /* Isolate the body structure and remove beginning and end parenthesis. */
  36     $read = trim(substr ($bodystructure, strpos(strtolower($bodystructure), 'bodystructure') + 13));
  37     $read = trim(substr ($read, 0, -1));
  38     $i = 0;
  39     $msg = Message::parseStructure($read,$i);
  40     if (!is_object($msg)) {
  41         include_once(SM_PATH . 'functions/display_messages.php');
  42         global $color, $mailbox;
  43         /* removed urldecode because $_GET is auto urldecoded ??? */
  44         displayPageHeader( $color, $mailbox );
  45         $errormessage  = _("SquirrelMail could not decode the bodystructure of the message");
  46         $errormessage .= '<br />'._("the provided bodystructure by your imap-server").':<br /><br />';
  47         $errormessage .= '<pre>' . htmlspecialchars($read) . '</pre>';
  48         plain_error_message( $errormessage, $color );
  49         echo '</body></html>';
  50         exit;
  51     }
  52     if (count($flags)) {
  53         foreach ($flags as $flag) {
  54             $char = strtoupper($flag{1});
  55             switch ($char) {
  56                 case 'S':
  57                     if (strtolower($flag) == '\\seen') {
  58                         $msg->is_seen = true;
  59                     }
  60                     break;
  61                 case 'A':
  62                     if (strtolower($flag) == '\\answered') {
  63                         $msg->is_answered = true;
  64                     }
  65                     break;
  66                 case 'D':
  67                     if (strtolower($flag) == '\\deleted') {
  68                         $msg->is_deleted = true;
  69                     }
  70                     break;
  71                 case 'F':
  72                     if (strtolower($flag) == '\\flagged') {
  73                         $msg->is_flagged = true;
  74                     }
  75                     break;
  76                 case 'M':
  77                     if (strtolower($flag) == '$mdnsent') {
  78                         $msg->is_mdnsent = true;
  79                     }
  80                     break;
  81                 default:
  82                     break;
  83             }
  84         }
  85     }
  86     //    listEntities($msg);
  87     return $msg;
  88 }
  89
  90
  91
  92 /* This starts the parsing of a particular structure.  It is called recursively,
  93 * so it can be passed different structures.  It returns an object of type
  94 * $message.
  95 * First, it checks to see if it is a multipart message.  If it is, then it
  96 * handles that as it sees is necessary.  If it is just a regular entity,
  97 * then it parses it and adds the necessary header information (by calling out
  98 * to mime_get_elements()
  99 */
 100
 101 function mime_fetch_body($imap_stream, $id, $ent_id=1, $fetch_size=0) {
 102     /* Do a bit of error correction.  If we couldn't find the entity id, just guess
 103     * that it is the first one.  That is usually the case anyway.
 104     */
 105
 106     if (!$ent_id) {
 107         $cmd = "FETCH $id BODY[]";
 108     } else {
 109         $cmd = "FETCH $id BODY[$ent_id]";
 110     }
 111
 112     if ($fetch_size!=0) $cmd .= "<0.$fetch_size>";
 113
 114     $data = sqimap_run_command ($imap_stream, $cmd, true, $response, $message, TRUE);
 115     do {
 116         $topline = trim(array_shift($data));
 117     } while($topline && ($topline[0] == '*') && !preg_match('/\* [0-9]+ FETCH.*/i', $topline)) ;
 118
 119     $wholemessage = implode('', $data);
 120     if (ereg('\\{([^\\}]*)\\}', $topline, $regs)) {
 121         $ret = substr($wholemessage, 0, $regs[1]);
 122         /* There is some information in the content info header that could be important
 123         * in order to parse html messages. Let's get them here.
 124         */
 125 //        if ($ret{0} == '<') {
 126 //            $data = sqimap_run_command ($imap_stream, "FETCH $id BODY[$ent_id.MIME]", true, $response, $message, TRUE);
 127 //        }
 128     } else if (ereg('"([^"]*)"', $topline, $regs)) {
 129         $ret = $regs[1];
 130     } else {
 131         global $where, $what, $mailbox, $passed_id, $startMessage;
 132         $par = 'mailbox=' . urlencode($mailbox) . '&amp;passed_id=' . $passed_id;
 133         if (isset($where) && isset($what)) {
 134             $par .= '&amp;where=' . urlencode($where) . '&amp;what=' . urlencode($what);
 135         } else {
 136             $par .= '&amp;startMessage=' . $startMessage . '&amp;show_more=0';
 137         }
 138         $par .= '&amp;response=' . urlencode($response) .
 139                 '&amp;message='  . urlencode($message)  .
 140                 '&amp;topline='  . urlencode($topline);
 141
 142         echo   '<tt><br />' .
 143             '<table width="80%"><tr>' .
 144             '<tr><td colspan="2">' .
 145             _("Body retrieval error. The reason for this is most probably that the message is malformed.") .
 146             '</td></tr>' .
 147             '<tr><td><b>' . _("Command:") . "</td><td>$cmd</td></tr>" .
 148             '<tr><td><b>' . _("Response:") . "</td><td>$response</td></tr>" .
 149             '<tr><td><b>' . _("Message:") . "</td><td>$message</td></tr>" .
 150             '<tr><td><b>' . _("FETCH line:") . "</td><td>$topline</td></tr>" .
 151             "</table><br /></tt></font><hr />";
 152
 153         $data = sqimap_run_command ($imap_stream, "FETCH $passed_id BODY[]", true, $response, $message, TRUE);
 154         array_shift($data);
 155         $wholemessage = implode('', $data);
 156
 157         $ret = $wholemessage;
 158     }
 159     return $ret;
 160 }
 161
 162 function mime_print_body_lines ($imap_stream, $id, $ent_id=1, $encoding, $rStream='php://stdout') {
 163
 164     /* Don't kill the connection if the browser is over a dialup
 165     * and it would take over 30 seconds to download it.
 166     * Don't call set_time_limit in safe mode.
 167     */
 168
 169     if (!ini_get('safe_mode')) {
 170         set_time_limit(0);
 171     }
 172     /* in case of base64 encoded attachments, do not buffer them.
 173     Instead, echo the decoded attachment directly to screen */
 174     if (strtolower($encoding) == 'base64') {
 175         if (!$ent_id) {
 176             $query = "FETCH $id BODY[]";
 177         } else {
 178             $query = "FETCH $id BODY[$ent_id]";
 179         }
 180         sqimap_run_command($imap_stream,$query,true,$response,$message,TRUE,'sqimap_base64_decode',$rStream,true);
 181     } else {
 182         $body = mime_fetch_body ($imap_stream, $id, $ent_id);
 183         if (is_resource($rStream)) {
 184             fputs($rStream,decodeBody($body,$encoding));
 185         } else {
 186             echo decodeBody($body, $encoding);
 187         }
 188     }
 189
 190     /*
 191     TODO, use the same method for quoted printable.
 192     However, I assume that quoted printable attachments aren't that large
 193     so the performancegain / memory usage drop will be minimal.
 194     If we decide to add that then we need to adapt sqimap_fread because
 195     we need to split te result on \n and fread doesn't stop at \n. That
 196     means we also should provide $results from sqimap_fread (by ref) to
 197     te function and set $no_return to false. The $filter function for
 198     quoted printable should handle unsetting of $results.
 199     */
 200     /*
 201     TODO 2: find out how we write to the output stream php://stdout. fwrite
 202     doesn't work because 'php://stdout isn't a stream.
 203     */
 204
 205     return;
 206 }
 207
 208 /* -[ END MIME DECODING ]----------------------------------------------------------- */
 209
 210 /* This is here for debugging purposes.  It will print out a list
 211 * of all the entity IDs that are in the $message object.
 212 */
 213 function listEntities ($message) {
 214     if ($message) {
 215         echo "<tt>" . $message->entity_id . ' : ' . $message->type0 . '/' . $message->type1 . ' parent = '. $message->parent->entity_id. '<br />';
 216         for ($i = 0; isset($message->entities[$i]); $i++) {
 217             echo "$i : ";
 218             $msg = listEntities($message->entities[$i]);
 219
 220             if ($msg) {
 221                 echo "return: ";
 222                 return $msg;
 223             }
 224         }
 225     }
 226 }
 227
 228 function getPriorityStr($priority) {
 229     $priority_level = substr($priority,0,1);
 230
 231     switch($priority_level) {
 232         /* Check for a higher then normal priority. */
 233         case '1':
 234         case '2':
 235             $priority_string = _("High");
 236             break;
 237
 238         /* Check for a lower then normal priority. */
 239         case '4':
 240         case '5':
 241             $priority_string = _("Low");
 242             break;
 243
 244         /* Check for a normal priority. */
 245         case '3':
 246         default:
 247             $priority_level = '3';
 248             $priority_string = _("Normal");
 249             break;
 250
 251     }
 252     return $priority_string;
 253 }
 254
 255 /* returns a $message object for a particular entity id */
 256 function getEntity ($message, $ent_id) {
 257     return $message->getEntity($ent_id);
 258 }
 259
 260 /* translateText
 261 * Extracted from strings.php 23/03/2002
 262 */
 263
 264 function translateText(&$body, $wrap_at, $charset) {
 265     global $where, $what;   /* from searching */
 266     global $color;          /* color theme */
 267
 268     require_once(SM_PATH . 'functions/url_parser.php');
 269
 270     $body_ary = explode("\n", $body);
 271     for ($i=0; $i < count($body_ary); $i++) {
 272         $line = $body_ary[$i];
 273         if (strlen($line) - 2 >= $wrap_at) {
 274             sqWordWrap($line, $wrap_at, $charset);
 275         }
 276         $line = charset_decode($charset, $line);
 277         $line = str_replace("\t", '        ', $line);
 278
 279         parseUrl ($line);
 280
 281         $quotes = 0;
 282         $pos = 0;
 283         $j = strlen($line);
 284
 285         while ($pos < $j) {
 286             if ($line[$pos] == ' ') {
 287                 $pos++;
 288             } else if (strpos($line, '&gt;', $pos) === $pos) {
 289                 $pos += 4;
 290                 $quotes++;
 291             } else {
 292                 break;
 293             }
 294         }
 295
 296         if ($quotes % 2) {
 297             if (!isset($color[13])) {
 298                 $color[13] = '#800000';
 299             }
 300             $line = '<font color="' . $color[13] . '">' . $line . '</font>';
 301         } elseif ($quotes) {
 302             if (!isset($color[14])) {
 303                 $color[14] = '#FF0000';
 304             }
 305             $line = '<font color="' . $color[14] . '">' . $line . '</font>';
 306         }
 307
 308         $body_ary[$i] = $line;
 309     }
 310     $body = '<pre>' . implode("\n", $body_ary) . '</pre>';
 311 }
 312
 313 /**
 314  * This returns a parsed string called $body. That string can then
 315  * be displayed as the actual message in the HTML. It contains
 316  * everything needed, including HTML Tags, Attachments at the
 317  * bottom, etc.
 318  *
 319  * Since 1.2.0 function uses message_body hook.
 320  * Till 1.3.0 function included output of formatAttachments().
 321  *
 322  * @param resource $imap_stream imap connection resource
 323  * @param object $message squirrelmail message object
 324  * @param array $color squirrelmail color theme array
 325  * @param integer $wrap_at number of characters per line
 326  * @param string $ent_num (since 1.3.0) message part id
 327  * @param integer $id (since 1.3.0) message id
 328  * @param string $mailbox (since 1.3.0) imap folder name
 329  * @param boolean $clean (since 1.5.1) Do not output stuff that's irrelevant for the printable version.
 330  * @return string html formated message text
 331  */
 332 function formatBody($imap_stream, $message, $color, $wrap_at, $ent_num, $id, $mailbox='INBOX', $clean=FALSE) {
 333     /* This if statement checks for the entity to show as the
 334     * primary message. To add more of them, just put them in the
 335     * order that is their priority.
 336     */
 337     global $startMessage, $languages, $squirrelmail_language,
 338         $show_html_default, $sort, $has_unsafe_images, $passed_ent_id, $use_iframe,$iframe_height;
 339
 340     // workaround for not updated config.php
 341     if (! isset($use_iframe)) $use_iframe = false;
 342
 343     if( !sqgetGlobalVar('view_unsafe_images', $view_unsafe_images, SQ_GET) ) {
 344         $view_unsafe_images = false;
 345     }
 346
 347     $body = '';
 348     $urlmailbox = urlencode($mailbox);
 349     $body_message = getEntity($message, $ent_num);
 350     if (($body_message->header->type0 == 'text') ||
 351         ($body_message->header->type0 == 'rfc822')) {
 352         $body = mime_fetch_body ($imap_stream, $id, $ent_num);
 353         $body = decodeBody($body, $body_message->header->encoding);
 354
 355         if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 356             function_exists($languages[$squirrelmail_language]['XTRA_CODE'] . '_decode')) {
 357             if (mb_detect_encoding($body) != 'ASCII') {
 358                 $body = call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_decode',$body);
 359             }
 360         }
 361         $hookResults = do_hook("message_body", $body);
 362         $body = $hookResults[1];
 363
 364         /* If there are other types that shouldn't be formatted, add
 365         * them here.
 366         */
 367
 368         if ($body_message->header->type1 == 'html') {
 369             if ($show_html_default <> 1) {
 370                 $entity_conv = array('&nbsp;' => ' ',
 371                                     '<p>'    => "\n",
 372                                     '<P>'    => "\n",
 373                                     '<br>'   => "\n",
 374                                     '<BR>'   => "\n",
 375                                     '<br />' => "\n",
 376                                     '<BR />' => "\n",
 377                                     '&gt;'   => '>',
 378                                     '&lt;'   => '<');
 379                 $body = strtr($body, $entity_conv);
 380                 $body = strip_tags($body);
 381                 $body = trim($body);
 382                 translateText($body, $wrap_at,
 383                             $body_message->header->getParameter('charset'));
 384             } elseif ($use_iframe && ! $clean) {
 385                 // $clean is used to remove iframe in printable view.
 386
 387                 /**
 388                  * If we don't add html message between iframe tags,
 389                  * we must detect unsafe images and modify $has_unsafe_images.
 390                  */
 391                 $html_body =  magicHTML($body, $id, $message, $mailbox);
 392
 393                 // creating iframe url
 394                 $iframeurl=sqm_baseuri().'src/view_html.php?'
 395                     . 'mailbox=' . $urlmailbox
 396                     . '&amp;passed_id=' . $id
 397                     . '&amp;ent_id=' . $ent_num
 398                     . '&amp;view_unsafe_images=' . (int) $view_unsafe_images;
 399
 400                 // adding warning message
 401                 $body = html_tag('div',_("Viewing HTML formatted email"),'center');
 402
 403                 /**
 404                  * height can't be set to 100%, because it does not work as expected when
 405                  * iframe is inside the table. Browsers do not create full height objects
 406                  * even when iframe is not nested. Maybe there is some way to get full size
 407                  * with CSS. Tested in firefox 1.02 and opera 7.53
 408                  *
 409                  * width="100%" does not work as expected, when table width is not set (automatic)
 410                  *
 411                  * tokul: I think <iframe> are safer sandbox than <object>. Objects might
 412                  * need special handling for IE and IE6SP2.
 413                  */
 414                 $body.= "<div><iframe name=\"message_frame\" width=\"100%\" height=\"$iframe_height\" src=\"$iframeurl\""
 415                     .' frameborder="1" marginwidth="0" marginheight="0" scrolling="auto">' . "\n";
 416
 417                 // Message for browsers without iframe support
 418                 //$body.= _("Your browser does not support inline frames.
 419                 // You can view HTML formated message by following below link.");
 420                 //$body.= "<br /><a href=\"$iframeurl\">"._("View HTML Message")."</a>";
 421
 422                 // if browser can't render iframe, it renders html message.
 423                 $body.= $html_body;
 424
 425                 // close iframe
 426                 $body.="</iframe></div>\n";
 427             } else {
 428                 // old way of html rendering
 429                 $body = magicHTML($body, $id, $message, $mailbox);
 430             }
 431         } else {
 432             translateText($body, $wrap_at,
 433                         $body_message->header->getParameter('charset'));
 434         }
 435
 436         // if this is the clean display (i.e. printer friendly), stop here.
 437         if ( $clean ) {
 438             return $body;
 439         }
 440
 441         $link = 'passed_id=' . $id . '&amp;ent_id='.$ent_num.
 442                 '&amp;mailbox=' . $urlmailbox .'&amp;sort=' . $sort .
 443                 '&amp;startMessage=' . $startMessage . '&amp;show_more=0';
 444         if (isset($passed_ent_id)) {
 445             $link .= '&amp;passed_ent_id='.$passed_ent_id;
 446         }
 447         $body .= '<center><small><a href="download.php?absolute_dl=true&amp;' .
 448                 $link . '">' . _("Download this as a file") .  '</a>';
 449         if ($view_unsafe_images) {
 450             $text = _("Hide Unsafe Images");
 451         } else {
 452             if (isset($has_unsafe_images) && $has_unsafe_images) {
 453                 $link .= '&amp;view_unsafe_images=1';
 454                 $text = _("View Unsafe Images");
 455             } else {
 456                 $text = '';
 457             }
 458         }
 459         if($text != '') {
 460             $body .= '&nbsp;|&nbsp;<a href="read_body.php?' . $link . '">' . $text . '</a>';
 461         }
 462         $body .= '</small></center><br />' . "\n";
 463     }
 464     return $body;
 465 }
 466
 467 /**
 468  * Displays attachment links and information
 469  *
 470  * Since 1.3.0 function is not included in formatBody() call.
 471  *
 472  * Since 1.0.2 uses attachment $type0/$type1 hook.
 473  * Since 1.2.5 uses attachment $type0/* hook.
 474  * Since 1.5.0 uses attachments_bottom hook.
 475  *
 476  * @param object $message SquirrelMail message object
 477  * @param array $exclude_id message parts that are not attachments.
 478  * @param string $mailbox mailbox name
 479  * @param integer $id message id
 480  * @return string html formated attachment information.
 481  */
 482 function formatAttachments($message, $exclude_id, $mailbox, $id) {
 483     global $where, $what, $startMessage, $color, $passed_ent_id;
 484
 485     $att_ar = $message->getAttachments($exclude_id);
 486
 487     if (!count($att_ar)) return '';
 488
 489     $attachments = '';
 490
 491     $urlMailbox = urlencode($mailbox);
 492
 493     foreach ($att_ar as $att) {
 494         $ent = $att->entity_id;
 495         $header = $att->header;
 496         $type0 = strtolower($header->type0);
 497         $type1 = strtolower($header->type1);
 498         $name = '';
 499         $links['download link']['text'] = _("Download");
 500         $links['download link']['href'] = sqm_baseuri() .
 501                 "src/download.php?absolute_dl=true&amp;passed_id=$id&amp;mailbox=$urlMailbox&amp;ent_id=$ent";
 502         if ($type0 =='message' && $type1 == 'rfc822') {
 503             $default_page = sqm_baseuri() . 'src/read_body.php';
 504             $rfc822_header = $att->rfc822_header;
 505             $filename = $rfc822_header->subject;
 506             if (trim( $filename ) == '') {
 507                 $filename = 'untitled-[' . $ent . ']' ;
 508             }
 509             $from_o = $rfc822_header->from;
 510             if (is_object($from_o)) {
 511                 $from_name = decodeHeader($from_o->getAddress(false));
 512             } else {
 513                 $from_name = _("Unknown sender");
 514             }
 515             $description = $from_name;
 516         } else {
 517             $default_page = sqm_baseuri() . 'src/download.php';
 518             $filename = $att->getFilename();
 519             if ($header->description) {
 520                 $description = decodeHeader($header->description);
 521             } else {
 522                 $description = '';
 523             }
 524         }
 525
 526         $display_filename = $filename;
 527         if (isset($passed_ent_id)) {
 528             $passed_ent_id_link = '&amp;passed_ent_id='.$passed_ent_id;
 529         } else {
 530             $passed_ent_id_link = '';
 531         }
 532         $defaultlink = $default_page . "?startMessage=$startMessage"
 533                     . "&amp;passed_id=$id&amp;mailbox=$urlMailbox"
 534                     . '&amp;ent_id='.$ent.$passed_ent_id_link;
 535         if ($where && $what) {
 536         $defaultlink .= '&amp;where='. urlencode($where).'&amp;what='.urlencode($what);
 537         }
 538
 539         /* This executes the attachment hook with a specific MIME-type.
 540         * If that doesn't have results, it tries if there's a rule
 541         * for a more generic type.
 542         */
 543         $hookresults = do_hook("attachment $type0/$type1", $links,
 544                             $startMessage, $id, $urlMailbox, $ent, $defaultlink,
 545                             $display_filename, $where, $what);
 546         if(count($hookresults[1]) <= 1) {
 547             $hookresults = do_hook("attachment $type0/*", $links,
 548                                 $startMessage, $id, $urlMailbox, $ent, $defaultlink,
 549                                 $display_filename, $where, $what);
 550         }
 551
 552         $links = $hookresults[1];
 553         $defaultlink = $hookresults[6];
 554
 555         $attachments .= '<tr><td>' .
 556                         '<a href="'.$defaultlink.'">'.decodeHeader($display_filename).'</a>&nbsp;</td>' .
 557                         '<td><small><b>' . show_readable_size($header->size) .
 558                         '</b>&nbsp;&nbsp;</small></td>' .
 559                         '<td><small>[ '.htmlspecialchars($type0).'/'.htmlspecialchars($type1).' ]&nbsp;</small></td>' .
 560                         '<td><small>';
 561         $attachments .= '<b>' . $description . '</b>';
 562         $attachments .= '</small></td><td><small>&nbsp;';
 563
 564         $skipspaces = 1;
 565         foreach ($links as $val) {
 566             if ($skipspaces) {
 567                 $skipspaces = 0;
 568             } else {
 569                 $attachments .= '&nbsp;&nbsp;|&nbsp;&nbsp;';
 570             }
 571             $attachments .= '<a href="' . $val['href'] . '">'
 572                 . (isset($val['text']) && !empty($val['text']) ? $val['text'] : '')
 573                 . (isset($val['extra']) && !empty($val['extra']) ? $val['extra'] : '')
 574                 . '</a>';
 575         }
 576         unset($links);
 577         $attachments .= "</td></tr>\n";
 578     }
 579     $attachmentadd = do_hook_function('attachments_bottom',$attachments);
 580     if ($attachmentadd != '')
 581         $attachments = $attachmentadd;
 582     return $attachments;
 583 }
 584
 585 function sqimap_base64_decode(&$string) {
 586
 587     // Base64 encoded data goes in pairs of 4 bytes. To achieve on the
 588     // fly decoding (to reduce memory usage) you have to check if the
 589     // data has incomplete pairs
 590
 591     // Remove the noise in order to check if the 4 bytes pairs are complete
 592     $string = str_replace(array("\r\n","\n", "\r", " "),array('','','',''),$string);
 593
 594     $sStringRem = '';
 595     $iMod = strlen($string) % 4;
 596     if ($iMod) {
 597         $sStringRem = substr($string,-$iMod);
 598         // Check if $sStringRem contains padding characters
 599         if (substr($sStringRem,-1) != '=') {
 600             $string = substr($string,0,-$iMod);
 601         } else {
 602             $sStringRem = '';
 603         }
 604     }
 605     $string = base64_decode($string);
 606     return $sStringRem;
 607 }
 608
 609
 610 /* This function decodes the body depending on the encoding type. */
 611 function decodeBody($body, $encoding) {
 612     global $show_html_default;
 613
 614     $body = str_replace("\r\n", "\n", $body);
 615     $encoding = strtolower($encoding);
 616
 617     $encoding_handler = do_hook_function('decode_body', $encoding);
 618
 619
 620     // plugins get first shot at decoding the body
 621     //
 622     if (!empty($encoding_handler) && function_exists($encoding_handler)) {
 623         $body = $encoding_handler('decode', $body);
 624
 625     } else if ($encoding == 'quoted-printable' ||
 626         $encoding == 'quoted_printable') {
 627         $body = quoted_printable_decode($body);
 628
 629         while (ereg("=\n", $body)) {
 630             $body = ereg_replace ("=\n", '', $body);
 631         }
 632
 633     } else if ($encoding == 'base64') {
 634         $body = base64_decode($body);
 635     }
 636
 637     // All other encodings are returned raw.
 638     return $body;
 639 }
 640
 641 /**
 642 * Decodes headers
 643 *
 644 * This functions decode strings that is encoded according to
 645 * RFC1522 (MIME Part Two: Message Header Extensions for Non-ASCII Text).
 646 * Patched by Christian Schmidt <christian@ostenfeld.dk>  23/03/2002
 647 *
 648 * @param string $string header string that has to be made readable
 649 * @param boolean $utfencode change message in order to be readable on user's charset. defaults to true
 650 * @param boolean $htmlsave preserve spaces and sanitize html special characters. defaults to true
 651 * @param boolean $decide decide if string can be utfencoded. defaults to false
 652 * @return string decoded header string
 653 */
 654 function decodeHeader ($string, $utfencode=true,$htmlsave=true,$decide=false) {
 655     global $languages, $squirrelmail_language,$default_charset;
 656     if (is_array($string)) {
 657         $string = implode("\n", $string);
 658     }
 659
 660     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 661         function_exists($languages[$squirrelmail_language]['XTRA_CODE'] . '_decodeheader')) {
 662         $string = call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_decodeheader', $string);
 663         // Do we need to return at this point?
 664         // return $string;
 665     }
 666     $i = 0;
 667     $iLastMatch = -2;
 668     $encoded = true;
 669
 670     $aString = explode(' ',$string);
 671     $ret = '';
 672     foreach ($aString as $chunk) {
 673         if ($encoded && $chunk === '') {
 674             continue;
 675         } elseif ($chunk === '') {
 676             $ret .= ' ';
 677             continue;
 678         }
 679         $encoded = false;
 680         /* if encoded words are not separated by a linear-space-white we still catch them */
 681         $j = $i-1;
 682
 683         while ($match = preg_match('/^(.*)=\?([^?]*)\?(Q|B)\?([^?]*)\?=(.*)$/Ui',$chunk,$res)) {
 684             /* if the last chunk isn't an encoded string then put back the space, otherwise don't */
 685             if ($iLastMatch !== $j) {
 686                 if ($htmlsave) {
 687                     $ret .= '&#32;';
 688                 } else {
 689                     $ret .= ' ';
 690                 }
 691             }
 692             $iLastMatch = $i;
 693             $j = $i;
 694             if ($htmlsave) {
 695                 $ret .= htmlspecialchars($res[1]);
 696             } else {
 697                 $ret .= $res[1];
 698             }
 699             $encoding = ucfirst($res[3]);
 700
 701             /* decide about valid decoding */
 702             if ($decide && is_conversion_safe($res[2])) {
 703             $utfencode=true;
 704             $can_be_encoded=true;
 705             } else {
 706             $can_be_encoded=false;
 707             }
 708             switch ($encoding)
 709             {
 710             case 'B':
 711                 $replace = base64_decode($res[4]);
 712                 if ($utfencode) {
 713                     if ($can_be_encoded) {
 714                         /* convert string to different charset,
 715                         * if functions asks for it (usually in compose)
 716                         */
 717                         $ret .= charset_convert($res[2],$replace,$default_charset);
 718                     } else {
 719                         // convert string to html codes in order to display it
 720                         $ret .= charset_decode($res[2],$replace);
 721                     }
 722                 } else {
 723                     if ($htmlsave) {
 724                         $replace = htmlspecialchars($replace);
 725                     }
 726                     $ret.= $replace;
 727                 }
 728                 break;
 729             case 'Q':
 730                 $replace = str_replace('_', ' ', $res[4]);
 731                 $replace = preg_replace('/=([0-9a-f]{2})/ie', 'chr(hexdec("\1"))',
 732                                     $replace);
 733                 if ($utfencode) {
 734                 if ($can_be_encoded) {
 735                     /* convert string to different charset,
 736                     * if functions asks for it (usually in compose)
 737                     */
 738                     $replace = charset_convert($res[2], $replace,$default_charset);
 739                 } else {
 740                     // convert string to html codes in order to display it
 741                     $replace = charset_decode($res[2], $replace);
 742                 }
 743                 } else {
 744                     if ($htmlsave) {
 745                         $replace = htmlspecialchars($replace);
 746                     }
 747                 }
 748                 $ret .= $replace;
 749                 break;
 750             default:
 751                 break;
 752             }
 753             $chunk = $res[5];
 754             $encoded = true;
 755         }
 756         if (!$encoded) {
 757             if ($htmlsave) {
 758                 $ret .= '&#32;';
 759             } else {
 760                 $ret .= ' ';
 761             }
 762         }
 763
 764         if (!$encoded && $htmlsave) {
 765             $ret .= htmlspecialchars($chunk);
 766         } else {
 767             $ret .= $chunk;
 768         }
 769         ++$i;
 770     }
 771     /* remove the first added space */
 772     if ($ret) {
 773         if ($htmlsave) {
 774             $ret = substr($ret,5);
 775         } else {
 776             $ret = substr($ret,1);
 777         }
 778     }
 779
 780     return $ret;
 781 }
 782
 783 /**
 784 * Encodes header as quoted-printable
 785 *
 786 * Encode a string according to RFC 1522 for use in headers if it
 787 * contains 8-bit characters or anything that looks like it should
 788 * be encoded.
 789 *
 790 * @param string $string header string, that has to be encoded
 791 * @return string quoted-printable encoded string
 792 */
 793 function encodeHeader ($string) {
 794     global $default_charset, $languages, $squirrelmail_language;
 795
 796     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 797         function_exists($languages[$squirrelmail_language]['XTRA_CODE'] . '_encodeheader')) {
 798         return  call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_encodeheader', $string);
 799     }
 800
 801     // Encode only if the string contains 8-bit characters or =?
 802     $j = strlen($string);
 803     $max_l = 75 - strlen($default_charset) - 7;
 804     $aRet = array();
 805     $ret = '';
 806     $iEncStart = $enc_init = false;
 807     $cur_l = $iOffset = 0;
 808     for($i = 0; $i < $j; ++$i) {
 809         switch($string{$i})
 810         {
 811         case '=':
 812         case '<':
 813         case '>':
 814         case ',':
 815         case '?':
 816         case '_':
 817             if ($iEncStart === false) {
 818                 $iEncStart = $i;
 819             }
 820             $cur_l+=3;
 821             if ($cur_l > ($max_l-2)) {
 822                 /* if there is an stringpart that doesn't need encoding, add it */
 823                 $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 824                 $aRet[] = "=?$default_charset?Q?$ret?=";
 825                 $iOffset = $i;
 826                 $cur_l = 0;
 827                 $ret = '';
 828                 $iEncStart = false;
 829             } else {
 830                 $ret .= sprintf("=%02X",ord($string{$i}));
 831             }
 832             break;
 833         case '(':
 834         case ')':
 835             if ($iEncStart !== false) {
 836                 $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 837                 $aRet[] = "=?$default_charset?Q?$ret?=";
 838                 $iOffset = $i;
 839                 $cur_l = 0;
 840                 $ret = '';
 841                 $iEncStart = false;
 842             }
 843             break;
 844         case ' ':
 845             if ($iEncStart !== false) {
 846                 $cur_l++;
 847                 if ($cur_l > $max_l) {
 848                     $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 849                     $aRet[] = "=?$default_charset?Q?$ret?=";
 850                     $iOffset = $i;
 851                     $cur_l = 0;
 852                     $ret = '';
 853                     $iEncStart = false;
 854                 } else {
 855                     $ret .= '_';
 856                 }
 857             }
 858             break;
 859         default:
 860             $k = ord($string{$i});
 861             if ($k > 126) {
 862                 if ($iEncStart === false) {
 863                     // do not start encoding in the middle of a string, also take the rest of the word.
 864                     $sLeadString = substr($string,0,$i);
 865                     $aLeadString = explode(' ',$sLeadString);
 866                     $sToBeEncoded = array_pop($aLeadString);
 867                     $iEncStart = $i - strlen($sToBeEncoded);
 868                     $ret .= $sToBeEncoded;
 869                     $cur_l += strlen($sToBeEncoded);
 870                 }
 871                 $cur_l += 3;
 872                 /* first we add the encoded string that reached it's max size */
 873                 if ($cur_l > ($max_l-2)) {
 874                     $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 875                     $aRet[] = "=?$default_charset?Q?$ret?= "; /* the next part is also encoded => separate by space */
 876                     $cur_l = 3;
 877                     $ret = '';
 878                     $iOffset = $i;
 879                     $iEncStart = $i;
 880                 }
 881                 $enc_init = true;
 882                 $ret .= sprintf("=%02X", $k);
 883             } else {
 884                 if ($iEncStart !== false) {
 885                     $cur_l++;
 886                     if ($cur_l > $max_l) {
 887                         $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 888                         $aRet[] = "=?$default_charset?Q?$ret?=";
 889                         $iEncStart = false;
 890                         $iOffset = $i;
 891                         $cur_l = 0;
 892                         $ret = '';
 893                     } else {
 894                         $ret .= $string{$i};
 895                     }
 896                 }
 897             }
 898             break;
 899         }
 900     }
 901
 902     if ($enc_init) {
 903         if ($iEncStart !== false) {
 904             $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 905             $aRet[] = "=?$default_charset?Q?$ret?=";
 906         } else {
 907             $aRet[] = substr($string,$iOffset);
 908         }
 909         $string = implode('',$aRet);
 910     }
 911     return $string;
 912 }
 913
 914 /* This function trys to locate the entity_id of a specific mime element */
 915 function find_ent_id($id, $message) {
 916     for ($i = 0, $ret = ''; $ret == '' && $i < count($message->entities); $i++) {
 917         if ($message->entities[$i]->header->type0 == 'multipart')  {
 918             $ret = find_ent_id($id, $message->entities[$i]);
 919         } else {
 920             if (strcasecmp($message->entities[$i]->header->id, $id) == 0) {
 921 //                if (sq_check_save_extension($message->entities[$i])) {
 922                     return $message->entities[$i]->entity_id;
 923 //                }
 924             } elseif (!empty($message->entities[$i]->header->parameters['name'])) {
 925                 /**
 926                  * This is part of a fix for Outlook Express 6.x generating
 927                  * cid URLs without creating content-id headers
 928                  * @@JA - 20050207
 929                  */
 930                 if (strcasecmp($message->entities[$i]->header->parameters['name'], $id) == 0) {
 931                     return $message->entities[$i]->entity_id;
 932                 }
 933             }
 934         }
 935     }
 936     return $ret;
 937 }
 938
 939 function sq_check_save_extension($message) {
 940     $filename = $message->getFilename();
 941     $ext = substr($filename, strrpos($filename,'.')+1);
 942     $save_extensions = array('jpg','jpeg','gif','png','bmp');
 943     return in_array($ext, $save_extensions);
 944 }
 945
 946
 947 /**
 948 ** HTMLFILTER ROUTINES
 949 */
 950
 951 /**
 952 * This function is more or less a wrapper around stripslashes. Apparently
 953 * Explorer is stupid enough to just remove the backslashes and then
 954 * execute the content of the attribute as if nothing happened.
 955 * Who does that?
 956 *
 957 * @param  attvalue   The value of the attribute
 958 * @return attvalue   The value of the attribute stripslashed.
 959 */
 960 function sq_unbackslash($attvalue){
 961     /**
 962     * Remove any backslashes. See if there are any first.
 963     */
 964
 965     if (strstr($attvalue, '\\') !== false){
 966         $attvalue = stripslashes($attvalue);
 967     }
 968     return $attvalue;
 969 }
 970
 971 /**
 972 * Kill any tabs, newlines, or carriage returns. Our friends the
 973 * makers of the browser with 95% market value decided that it'd
 974 * be funny to make "java[tab]script" be just as good as "javascript".
 975 *
 976 * @param  attvalue  The attribute value before extraneous spaces removed.
 977 * @return attvalue  The attribute value after extraneous spaces removed.
 978 */
 979 function sq_unspace($attvalue){
 980     if (strcspn($attvalue, "\t\r\n") != strlen($attvalue)){
 981         $attvalue = str_replace(Array("\t", "\r", "\n"), Array('', '', ''),
 982                                 $attvalue);
 983     }
 984     return $attvalue;
 985 }
 986
 987 /**
 988 * This function returns the final tag out of the tag name, an array
 989 * of attributes, and the type of the tag. This function is called by
 990 * sq_sanitize internally.
 991 *
 992 * @param  $tagname  the name of the tag.
 993 * @param  $attary   the array of attributes and their values
 994 * @param  $tagtype  The type of the tag (see in comments).
 995 * @return           a string with the final tag representation.
 996 */
 997 function sq_tagprint($tagname, $attary, $tagtype){
 998     $me = 'sq_tagprint';
 999
1000     if ($tagtype == 2){
1001         $fulltag = '</' . $tagname . '>';
1002     } else {
1003         $fulltag = '<' . $tagname;
1004         if (is_array($attary) && sizeof($attary)){
1005             $atts = Array();
1006             while (list($attname, $attvalue) = each($attary)){
1007                 array_push($atts, "$attname=$attvalue");
1008             }
1009             $fulltag .= ' ' . join(" ", $atts);
1010         }
1011         if ($tagtype == 3){
1012             $fulltag .= ' /';
1013         }
1014         $fulltag .= '>';
1015     }
1016     return $fulltag;
1017 }
1018
1019 /**
1020 * A small helper function to use with array_walk. Modifies a by-ref
1021 * value and makes it lowercase.
1022 *
1023 * @param  $val a value passed by-ref.
1024 * @return      void since it modifies a by-ref value.
1025 */
1026 function sq_casenormalize(&$val){
1027     $val = strtolower($val);
1028 }
1029
1030 /**
1031 * This function skips any whitespace from the current position within
1032 * a string and to the next non-whitespace value.
1033 *
1034 * @param  $body   the string
1035 * @param  $offset the offset within the string where we should start
1036 *                 looking for the next non-whitespace character.
1037 * @return         the location within the $body where the next
1038 *                 non-whitespace char is located.
1039 */
1040 function sq_skipspace($body, $offset){
1041     $me = 'sq_skipspace';
1042     preg_match('/^(\s*)/s', substr($body, $offset), $matches);
1043     if (sizeof($matches{1})){
1044         $count = strlen($matches{1});
1045         $offset += $count;
1046     }
1047     return $offset;
1048 }
1049
1050 /**
1051 * This function looks for the next character within a string.  It's
1052 * really just a glorified "strpos", except it catches if failures
1053 * nicely.
1054 *
1055 * @param  $body   The string to look for needle in.
1056 * @param  $offset Start looking from this position.
1057 * @param  $needle The character/string to look for.
1058 * @return         location of the next occurance of the needle, or
1059 *                 strlen($body) if needle wasn't found.
1060 */
1061 function sq_findnxstr($body, $offset, $needle){
1062     $me  = 'sq_findnxstr';
1063     $pos = strpos($body, $needle, $offset);
1064     if ($pos === FALSE){
1065         $pos = strlen($body);
1066     }
1067     return $pos;
1068 }
1069
1070 /**
1071 * This function takes a PCRE-style regexp and tries to match it
1072 * within the string.
1073 *
1074 * @param  $body   The string to look for needle in.
1075 * @param  $offset Start looking from here.
1076 * @param  $reg    A PCRE-style regex to match.
1077 * @return         Returns a false if no matches found, or an array
1078 *                 with the following members:
1079 *                 - integer with the location of the match within $body
1080 *                 - string with whatever content between offset and the match
1081 *                 - string with whatever it is we matched
1082 */
1083 function sq_findnxreg($body, $offset, $reg){
1084     $me = 'sq_findnxreg';
1085     $matches = Array();
1086     $retarr = Array();
1087     preg_match("%^(.*?)($reg)%si", substr($body, $offset), $matches);
1088     if (!isset($matches{0}) || !$matches{0}){
1089         $retarr = false;
1090     } else {
1091         $retarr{0} = $offset + strlen($matches{1});
1092         $retarr{1} = $matches{1};
1093         $retarr{2} = $matches{2};
1094     }
1095     return $retarr;
1096 }
1097
1098 /**
1099 * This function looks for the next tag.
1100 *
1101 * @param  $body   String where to look for the next tag.
1102 * @param  $offset Start looking from here.
1103 * @return         false if no more tags exist in the body, or
1104 *                 an array with the following members:
1105 *                 - string with the name of the tag
1106 *                 - array with attributes and their values
1107 *                 - integer with tag type (1, 2, or 3)
1108 *                 - integer where the tag starts (starting "<")
1109 *                 - integer where the tag ends (ending ">")
1110 *                 first three members will be false, if the tag is invalid.
1111 */
1112 function sq_getnxtag($body, $offset){
1113     $me = 'sq_getnxtag';
1114     if ($offset > strlen($body)){
1115         return false;
1116     }
1117     $lt = sq_findnxstr($body, $offset, "<");
1118     if ($lt == strlen($body)){
1119         return false;
1120     }
1121     /**
1122     * We are here:
1123     * blah blah <tag attribute="value">
1124     * \---------^
1125     */
1126     $pos = sq_skipspace($body, $lt+1);
1127     if ($pos >= strlen($body)){
1128         return Array(false, false, false, $lt, strlen($body));
1129     }
1130     /**
1131     * There are 3 kinds of tags:
1132     * 1. Opening tag, e.g.:
1133     *    <a href="blah">
1134     * 2. Closing tag, e.g.:
1135     *    </a>
1136     * 3. XHTML-style content-less tag, e.g.:
1137     *    <img src="blah" />
1138     */
1139     $tagtype = false;
1140     switch (substr($body, $pos, 1)){
1141         case '/':
1142             $tagtype = 2;
1143             $pos++;
1144             break;
1145         case '!':
1146             /**
1147             * A comment or an SGML declaration.
1148             */
1149             if (substr($body, $pos+1, 2) == "--"){
1150                 $gt = strpos($body, "-->", $pos);
1151                 if ($gt === false){
1152                     $gt = strlen($body);
1153                 } else {
1154                     $gt += 2;
1155                 }
1156                 return Array(false, false, false, $lt, $gt);
1157             } else {
1158                 $gt = sq_findnxstr($body, $pos, ">");
1159                 return Array(false, false, false, $lt, $gt);
1160             }
1161             break;
1162         default:
1163             /**
1164             * Assume tagtype 1 for now. If it's type 3, we'll switch values
1165             * later.
1166             */
1167             $tagtype = 1;
1168             break;
1169     }
1170
1171     $tagname = '';
1172     /**
1173     * Look for next [\W-_], which will indicate the end of the tag name.
1174     */
1175     $regary = sq_findnxreg($body, $pos, "[^\w\-_]");
1176     if ($regary == false){
1177         return Array(false, false, false, $lt, strlen($body));
1178     }
1179     list($pos, $tagname, $match) = $regary;
1180     $tagname = strtolower($tagname);
1181
1182     /**
1183     * $match can be either of these:
1184     * '>'  indicating the end of the tag entirely.
1185     * '\s' indicating the end of the tag name.
1186     * '/'  indicating that this is type-3 xhtml tag.
1187     *
1188     * Whatever else we find there indicates an invalid tag.
1189     */
1190     switch ($match){
1191         case '/':
1192             /**
1193             * This is an xhtml-style tag with a closing / at the
1194             * end, like so: <img src="blah" />. Check if it's followed
1195             * by the closing bracket. If not, then this tag is invalid
1196             */
1197             if (substr($body, $pos, 2) == "/>"){
1198                 $pos++;
1199                 $tagtype = 3;
1200             } else {
1201                 $gt = sq_findnxstr($body, $pos, ">");
1202                 $retary = Array(false, false, false, $lt, $gt);
1203                 return $retary;
1204             }
1205         case '>':
1206             return Array($tagname, false, $tagtype, $lt, $pos);
1207             break;
1208         default:
1209             /**
1210             * Check if it's whitespace
1211             */
1212             if (!preg_match('/\s/', $match)){
1213                 /**
1214                 * This is an invalid tag! Look for the next closing ">".
1215                 */
1216                 $gt = sq_findnxstr($body, $lt, ">");
1217                 return Array(false, false, false, $lt, $gt);
1218             }
1219             break;
1220     }
1221
1222     /**
1223     * At this point we're here:
1224     * <tagname  attribute='blah'>
1225     * \-------^
1226     *
1227     * At this point we loop in order to find all attributes.
1228     */
1229     $attname = '';
1230     $attary = Array();
1231
1232     while ($pos <= strlen($body)){
1233         $pos = sq_skipspace($body, $pos);
1234         if ($pos == strlen($body)){
1235             /**
1236             * Non-closed tag.
1237             */
1238             return Array(false, false, false, $lt, $pos);
1239         }
1240         /**
1241         * See if we arrived at a ">" or "/>", which means that we reached
1242         * the end of the tag.
1243         */
1244         $matches = Array();
1245         if (preg_match("%^(\s*)(>|/>)%s", substr($body, $pos), $matches)) {
1246             /**
1247             * Yep. So we did.
1248             */
1249             $pos += strlen($matches{1});
1250             if ($matches{2} == "/>"){
1251                 $tagtype = 3;
1252                 $pos++;
1253             }
1254             return Array($tagname, $attary, $tagtype, $lt, $pos);
1255         }
1256
1257         /**
1258         * There are several types of attributes, with optional
1259         * [:space:] between members.
1260         * Type 1:
1261         *   attrname[:space:]=[:space:]'CDATA'
1262         * Type 2:
1263         *   attrname[:space:]=[:space:]"CDATA"
1264         * Type 3:
1265         *   attr[:space:]=[:space:]CDATA
1266         * Type 4:
1267         *   attrname
1268         *
1269         * We leave types 1 and 2 the same, type 3 we check for
1270         * '"' and convert to "&quot" if needed, then wrap in
1271         * double quotes. Type 4 we convert into:
1272         * attrname="yes".
1273         */
1274         $regary = sq_findnxreg($body, $pos, "[^:\w\-_]");
1275         if ($regary == false){
1276             /**
1277             * Looks like body ended before the end of tag.
1278             */
1279             return Array(false, false, false, $lt, strlen($body));
1280         }
1281         list($pos, $attname, $match) = $regary;
1282         $attname = strtolower($attname);
1283         /**
1284         * We arrived at the end of attribute name. Several things possible
1285         * here:
1286         * '>'  means the end of the tag and this is attribute type 4
1287         * '/'  if followed by '>' means the same thing as above
1288         * '\s' means a lot of things -- look what it's followed by.
1289         *      anything else means the attribute is invalid.
1290         */
1291         switch($match){
1292             case '/':
1293                 /**
1294                 * This is an xhtml-style tag with a closing / at the
1295                 * end, like so: <img src="blah" />. Check if it's followed
1296                 * by the closing bracket. If not, then this tag is invalid
1297                 */
1298                 if (substr($body, $pos, 2) == "/>"){
1299                     $pos++;
1300                     $tagtype = 3;
1301                 } else {
1302                     $gt = sq_findnxstr($body, $pos, ">");
1303                     $retary = Array(false, false, false, $lt, $gt);
1304                     return $retary;
1305                 }
1306             case '>':
1307                 $attary{$attname} = '"yes"';
1308                 return Array($tagname, $attary, $tagtype, $lt, $pos);
1309                 break;
1310             default:
1311                 /**
1312                 * Skip whitespace and see what we arrive at.
1313                 */
1314                 $pos = sq_skipspace($body, $pos);
1315                 $char = substr($body, $pos, 1);
1316                 /**
1317                 * Two things are valid here:
1318                 * '=' means this is attribute type 1 2 or 3.
1319                 * \w means this was attribute type 4.
1320                 * anything else we ignore and re-loop. End of tag and
1321                 * invalid stuff will be caught by our checks at the beginning
1322                 * of the loop.
1323                 */
1324                 if ($char == "="){
1325                     $pos++;
1326                     $pos = sq_skipspace($body, $pos);
1327                     /**
1328                     * Here are 3 possibilities:
1329                     * "'"  attribute type 1
1330                     * '"'  attribute type 2
1331                     * everything else is the content of tag type 3
1332                     */
1333                     $quot = substr($body, $pos, 1);
1334                     if ($quot == "'"){
1335                         $regary = sq_findnxreg($body, $pos+1, "\'");
1336                         if ($regary == false){
1337                             return Array(false, false, false, $lt, strlen($body));
1338                         }
1339                         list($pos, $attval, $match) = $regary;
1340                         $pos++;
1341                         $attary{$attname} = "'" . $attval . "'";
1342                     } else if ($quot == '"'){
1343                         $regary = sq_findnxreg($body, $pos+1, '\"');
1344                         if ($regary == false){
1345                             return Array(false, false, false, $lt, strlen($body));
1346                         }
1347                         list($pos, $attval, $match) = $regary;
1348                         $pos++;
1349                         $attary{$attname} = '"' . $attval . '"';
1350                     } else {
1351                         /**
1352                         * These are hateful. Look for \s, or >.
1353                         */
1354                         $regary = sq_findnxreg($body, $pos, "[\s>]");
1355                         if ($regary == false){
1356                             return Array(false, false, false, $lt, strlen($body));
1357                         }
1358                         list($pos, $attval, $match) = $regary;
1359                         /**
1360                         * If it's ">" it will be caught at the top.
1361                         */
1362                         $attval = preg_replace("/\"/s", "&quot;", $attval);
1363                         $attary{$attname} = '"' . $attval . '"';
1364                     }
1365                 } else if (preg_match("|[\w/>]|", $char)) {
1366                     /**
1367                     * That was attribute type 4.
1368                     */
1369                     $attary{$attname} = '"yes"';
1370                 } else {
1371                     /**
1372                     * An illegal character. Find next '>' and return.
1373                     */
1374                     $gt = sq_findnxstr($body, $pos, ">");
1375                     return Array(false, false, false, $lt, $gt);
1376                 }
1377                 break;
1378         }
1379     }
1380     /**
1381     * The fact that we got here indicates that the tag end was never
1382     * found. Return invalid tag indication so it gets stripped.
1383     */
1384     return Array(false, false, false, $lt, strlen($body));
1385 }
1386
1387 /**
1388 * This function checks attribute values for entity-encoded values
1389 * and returns them translated into 8-bit strings so we can run
1390 * checks on them.
1391 *
1392 * @param  $attvalue A string to run entity check against.
1393 * @return           Translated value.
1394 */
1395
1396 function sq_deent($attvalue){
1397     $me = 'sq_deent';
1398     /**
1399     * See if we have to run the checks first. All entities must start
1400     * with "&".
1401     */
1402     if (strpos($attvalue, '&') === false){
1403         return $attvalue;
1404     }
1405     /**
1406     * Check named entities first.
1407     */
1408     $trans = get_html_translation_table(HTML_ENTITIES);
1409     /**
1410     * Leave &quot; in, as it can mess us up.
1411     */
1412     $trans = array_flip($trans);
1413     unset($trans{'&quot;'});
1414     while (list($ent, $val) = each($trans)){
1415         $attvalue = preg_replace('/' . $ent . '*/si', $val, $attvalue);
1416     }
1417     /**
1418     * Now translate numbered entities from 1 to 255 if needed.
1419     */
1420     if (strpos($attvalue, '#') !== false){
1421         $omit = Array(34, 39);
1422         for ($asc = 256; $asc >= 0; $asc--){
1423             if (!in_array($asc, $omit)){
1424                 $chr = chr($asc);
1425                 $octrule = '/\&#0*' . $asc . ';*/si';
1426                 $hexrule = '/\&#x0*' . dechex($asc) . ';*/si';
1427                 $attvalue = preg_replace($octrule, $chr, $attvalue);
1428                 $attvalue = preg_replace($hexrule, $chr, $attvalue);
1429             }
1430         }
1431     }
1432     return $attvalue;
1433 }
1434
1435 /**
1436 * This function runs various checks against the attributes.
1437 *
1438 * @param  $tagname         String with the name of the tag.
1439 * @param  $attary          Array with all tag attributes.
1440 * @param  $rm_attnames     See description for sq_sanitize
1441 * @param  $bad_attvals     See description for sq_sanitize
1442 * @param  $add_attr_to_tag See description for sq_sanitize
1443 * @param  $message         message object
1444 * @param  $id              message id
1445 * @return                  Array with modified attributes.
1446 */
1447 function sq_fixatts($tagname,
1448                     $attary,
1449                     $rm_attnames,
1450                     $bad_attvals,
1451                     $add_attr_to_tag,
1452                     $message,
1453                     $id,
1454                     $mailbox
1455                     ){
1456     $me = 'sq_fixatts';
1457     while (list($attname, $attvalue) = each($attary)){
1458         /**
1459         * See if this attribute should be removed.
1460         */
1461         foreach ($rm_attnames as $matchtag=>$matchattrs){
1462             if (preg_match($matchtag, $tagname)){
1463                 foreach ($matchattrs as $matchattr){
1464                     if (preg_match($matchattr, $attname)){
1465                         unset($attary{$attname});
1466                         continue;
1467                     }
1468                 }
1469             }
1470         }
1471         /**
1472         * Remove any backslashes, entities, and extraneous whitespace.
1473         */
1474         $attvalue = sq_unbackslash($attvalue);
1475         $attvalue = sq_deent($attvalue);
1476         $attvalue = sq_unspace($attvalue);
1477
1478         /**
1479         * Remove \r \n \t \0 " " "\\"
1480         */
1481         $attvalue = str_replace(Array("\r", "\n", "\t", "\0", " ", "\\"),
1482                         Array('', '','','','',''), $attvalue);
1483
1484         /**
1485         * Now let's run checks on the attvalues.
1486         * I don't expect anyone to comprehend this. If you do,
1487         * get in touch with me so I can drive to where you live and
1488         * shake your hand personally. :)
1489         */
1490         foreach ($bad_attvals as $matchtag=>$matchattrs){
1491             if (preg_match($matchtag, $tagname)){
1492                 foreach ($matchattrs as $matchattr=>$valary){
1493                     if (preg_match($matchattr, $attname)){
1494                         /**
1495                         * There are two arrays in valary.
1496                         * First is matches.
1497                         * Second one is replacements
1498                         */
1499                         list($valmatch, $valrepl) = $valary;
1500                         $newvalue =
1501                             preg_replace($valmatch, $valrepl, $attvalue);
1502                         if ($newvalue != $attvalue){
1503                             $attary{$attname} = $newvalue;
1504                         }
1505                     }
1506                 }
1507             }
1508         }
1509
1510
1511         /**
1512          * Replace empty src tags with the blank image.  src is only used
1513          * for frames, images, and image inputs.  Doing a replace should
1514          * not affect them working as should be, however it will stop
1515          * IE from being kicked off when src for img tags are not set
1516          */
1517         if (($attname == 'src') && ($attvalue == '""')) {
1518             $attary{$attname} = '"' . SM_PATH . 'images/blank.png"';
1519         }
1520
1521         /**
1522         * Turn cid: urls into http-friendly ones.
1523         */
1524         if (preg_match("/^[\'\"]\s*cid:/si", $attvalue)){
1525             $attary{$attname} = sq_cid2http($message, $id, $attvalue, $mailbox);
1526         }
1527
1528         /**
1529          * "Hack" fix for Outlook using propriatary outbind:// protocol in img tags.
1530          * One day MS might actually make it match something useful, for now, falling
1531          * back to using cid2http, so we can grab the blank.png.
1532          */
1533         if (preg_match("/^[\'\"]\s*outbind:\/\//si", $attvalue)) {
1534             $attary{$attname} = sq_cid2http($message, $id, $attvalue, $mailbox);
1535         }
1536
1537     }
1538     /**
1539     * See if we need to append any attributes to this tag.
1540     */
1541     foreach ($add_attr_to_tag as $matchtag=>$addattary){
1542         if (preg_match($matchtag, $tagname)){
1543             $attary = array_merge($attary, $addattary);
1544         }
1545     }
1546     return $attary;
1547 }
1548
1549 /**
1550 * This function edits the style definition to make them friendly and
1551 * usable in SquirrelMail.
1552 *
1553 * @param  $message  the message object
1554 * @param  $id       the message id
1555 * @param  $content  a string with whatever is between <style> and </style>
1556 * @param  $mailbox  the message mailbox
1557 * @return           a string with edited content.
1558 */
1559 function sq_fixstyle($body, $pos, $message, $id, $mailbox){
1560     global $view_unsafe_images;
1561     $me = 'sq_fixstyle';
1562     $ret = sq_findnxreg($body, $pos, '</\s*style\s*>');
1563     if ($ret == FALSE){
1564         return array(FALSE, strlen($body));
1565     }
1566     $newpos = $ret[0] + strlen($ret[2]);
1567     $content = $ret[1];
1568     /**
1569     * First look for general BODY style declaration, which would be
1570     * like so:
1571     * body {background: blah-blah}
1572     * and change it to .bodyclass so we can just assign it to a <div>
1573     */
1574     $content = preg_replace("|body(\s*\{.*?\})|si", ".bodyclass\\1", $content);
1575     $secremoveimg = '../images/' . _("sec_remove_eng.png");
1576     /**
1577     * Fix url('blah') declarations.
1578     */
1579     $content = preg_replace("|url\s*\(\s*([\'\"])\s*\S+script\s*:.*?([\'\"])\s*\)|si",
1580                             "url(\\1$secremoveimg\\2)", $content);
1581     /**
1582     * Fix url('https*://.*) declarations but only if $view_unsafe_images
1583     * is false.
1584     */
1585     if (!$view_unsafe_images){
1586         $content = preg_replace("|url\s*\(\s*([\'\"])\s*https*:.*?([\'\"])\s*\)|si",
1587                                 "url(\\1$secremoveimg\\2)", $content);
1588     }
1589
1590     /**
1591     * Fix urls that refer to cid:
1592     */
1593     while (preg_match("|url\s*\(\s*([\'\"]\s*cid:.*?[\'\"])\s*\)|si",
1594                     $content, $matches)){
1595         $cidurl = $matches{1};
1596         $httpurl = sq_cid2http($message, $id, $cidurl, $mailbox);
1597         $content = preg_replace("|url\s*\(\s*$cidurl\s*\)|si",
1598                                 "url($httpurl)", $content);
1599     }
1600
1601     /**
1602     * Fix stupid css declarations which lead to vulnerabilities
1603     * in IE.
1604     */
1605     $match   = Array('/expression/i',
1606                     '/behaviou*r/i',
1607                     '/binding/i',
1608                     '/include-source/i');
1609     $replace = Array('idiocy', 'idiocy', 'idiocy', 'idiocy');
1610     $content = preg_replace($match, $replace, $content);
1611     return array($content, $newpos);
1612 }
1613
1614 /**
1615 * This function converts cid: url's into the ones that can be viewed in
1616 * the browser.
1617 *
1618 * @param  $message  the message object
1619 * @param  $id       the message id
1620 * @param  $cidurl   the cid: url.
1621 * @param  $mailbox  the message mailbox
1622 * @return           a string with a http-friendly url
1623 */
1624 function sq_cid2http($message, $id, $cidurl, $mailbox){
1625     /**
1626     * Get rid of quotes.
1627     */
1628     $quotchar = substr($cidurl, 0, 1);
1629     if ($quotchar == '"' || $quotchar == "'"){
1630         $cidurl = str_replace($quotchar, "", $cidurl);
1631     } else {
1632         $quotchar = '';
1633     }
1634     $cidurl = substr(trim($cidurl), 4);
1635     $linkurl = find_ent_id($cidurl, $message);
1636     /* in case of non-save cid links $httpurl should be replaced by a sort of
1637     unsave link image */
1638     $httpurl = '';
1639
1640    /**
1641     * This is part of a fix for Outlook Express 6.x generating
1642     * cid URLs without creating content-id headers. These images are
1643     * not part of the multipart/related html mail. The html contains
1644     * <img src="cid:{some_id}/image_filename.ext"> references to
1645     * attached images with as goal to render them inline although
1646     * the attachment disposition property is not inline.
1647     **/
1648
1649     if (empty($linkurl)) {
1650         if (preg_match('/{.*}\//', $cidurl)) {
1651             $cidurl = preg_replace('/{.*}\//','', $cidurl);
1652             if (!empty($cidurl)) {
1653                 $linkurl = find_ent_id($cidurl, $message);
1654             }
1655         }
1656     }
1657
1658     if (!empty($linkurl)) {
1659         $httpurl = $quotchar . SM_PATH . 'src/download.php?absolute_dl=true&amp;' .
1660                    "passed_id=$id&amp;mailbox=" . urlencode($mailbox) .
1661                    '&amp;ent_id=' . $linkurl . $quotchar;
1662     } else {
1663         /**
1664          * If we couldn't generate a proper img url, drop in a blank image
1665          * instead of sending back empty, otherwise it causes unusual behaviour
1666          */
1667         $httpurl = $quotchar . SM_PATH . 'images/blank.png';
1668     }
1669
1670     return $httpurl;
1671 }
1672
1673 /**
1674 * This function changes the <body> tag into a <div> tag since we
1675 * can't really have a body-within-body.
1676 *
1677 * @param  $attary   an array of attributes and values of <body>
1678 * @param  $mailbox  mailbox we're currently reading (for cid2http)
1679 * @param  $message  current message (for cid2http)
1680 * @param  $id       current message id (for cid2http)
1681 * @return           a modified array of attributes to be set for <div>
1682 */
1683 function sq_body2div($attary, $mailbox, $message, $id){
1684     $me = 'sq_body2div';
1685     $divattary = Array('class' => "'bodyclass'");
1686     $text = '#000000';
1687     $has_bgc_stl = $has_txt_stl = false;
1688     $styledef = '';
1689     if (is_array($attary) && sizeof($attary) > 0){
1690         foreach ($attary as $attname=>$attvalue){
1691             $quotchar = substr($attvalue, 0, 1);
1692             $attvalue = str_replace($quotchar, "", $attvalue);
1693             switch ($attname){
1694                 case 'background':
1695                     $attvalue = sq_cid2http($message, $id,
1696                                             $attvalue, $mailbox);
1697                     $styledef .= "background-image: url('$attvalue'); ";
1698                     break;
1699                 case 'bgcolor':
1700                     $has_bgc_stl = true;
1701                     $styledef .= "background-color: $attvalue; ";
1702                     break;
1703                 case 'text':
1704                     $has_txt_stl = true;
1705                     $styledef .= "color: $attvalue; ";
1706                     break;
1707             }
1708         }
1709         // Outlook defines a white bgcolor and no text color. This can lead to
1710         // white text on a white bg with certain themes.
1711         if ($has_bgc_stl && !$has_txt_stl) {
1712             $styledef .= "color: $text; ";
1713         }
1714         if (strlen($styledef) > 0){
1715             $divattary{"style"} = "\"$styledef\"";
1716         }
1717     }
1718     return $divattary;
1719 }
1720
1721 /**
1722 * This is the main function and the one you should actually be calling.
1723 * There are several variables you should be aware of an which need
1724 * special description.
1725 *
1726 * Since the description is quite lengthy, see it here:
1727 * http://linux.duke.edu/projects/mini/htmlfilter/
1728 *
1729 * @param $body                 the string with HTML you wish to filter
1730 * @param $tag_list             see description above
1731 * @param $rm_tags_with_content see description above
1732 * @param $self_closing_tags    see description above
1733 * @param $force_tag_closing    see description above
1734 * @param $rm_attnames          see description above
1735 * @param $bad_attvals          see description above
1736 * @param $add_attr_to_tag      see description above
1737 * @param $message              message object
1738 * @param $id                   message id
1739 * @return                      sanitized html safe to show on your pages.
1740 */
1741 function sq_sanitize($body,
1742                     $tag_list,
1743                     $rm_tags_with_content,
1744                     $self_closing_tags,
1745                     $force_tag_closing,
1746                     $rm_attnames,
1747                     $bad_attvals,
1748                     $add_attr_to_tag,
1749                     $message,
1750                     $id,
1751                     $mailbox
1752                     ){
1753     $me = 'sq_sanitize';
1754     $rm_tags = array_shift($tag_list);
1755     /**
1756     * Normalize rm_tags and rm_tags_with_content.
1757     */
1758     @array_walk($tag_list, 'sq_casenormalize');
1759     @array_walk($rm_tags_with_content, 'sq_casenormalize');
1760     @array_walk($self_closing_tags, 'sq_casenormalize');
1761     /**
1762     * See if tag_list is of tags to remove or tags to allow.
1763     * false  means remove these tags
1764     * true   means allow these tags
1765     */
1766     $curpos = 0;
1767     $open_tags = Array();
1768     $trusted = "\n<!-- begin sanitized html -->\n";
1769     $skip_content = false;
1770     /**
1771     * Take care of netscape's stupid javascript entities like
1772     * &{alert('boo')};
1773     */
1774     $body = preg_replace("/&(\{.*?\};)/si", "&amp;\\1", $body);
1775
1776     while (($curtag = sq_getnxtag($body, $curpos)) != FALSE){
1777         list($tagname, $attary, $tagtype, $lt, $gt) = $curtag;
1778         $free_content = substr($body, $curpos, $lt-$curpos);
1779         /**
1780         * Take care of <style>
1781         */
1782         if ($tagname == "style" && $tagtype == 1){
1783             list($free_content, $curpos) =
1784                 sq_fixstyle($body, $gt+1, $message, $id, $mailbox);
1785             if ($free_content != FALSE){
1786                 $trusted .= sq_tagprint($tagname, $attary, $tagtype);
1787                 $trusted .= $free_content;
1788                 $trusted .= sq_tagprint($tagname, false, 2);
1789             }
1790             continue;
1791         }
1792         if ($skip_content == false){
1793             $trusted .= $free_content;
1794         }
1795         if ($tagname != FALSE){
1796             if ($tagtype == 2){
1797                 if ($skip_content == $tagname){
1798                     /**
1799                     * Got to the end of tag we needed to remove.
1800                     */
1801                     $tagname = false;
1802                     $skip_content = false;
1803                 } else {
1804                     if ($skip_content == false){
1805                         if ($tagname == "body"){
1806                             $tagname = "div";
1807                         }
1808                         if (isset($open_tags{$tagname}) &&
1809                             $open_tags{$tagname} > 0){
1810                             $open_tags{$tagname}--;
1811                         } else {
1812                             $tagname = false;
1813                         }
1814                     }
1815                 }
1816             } else {
1817                 /**
1818                 * $rm_tags_with_content
1819                 */
1820                 if ($skip_content == false){
1821                     /**
1822                     * See if this is a self-closing type and change
1823                     * tagtype appropriately.
1824                     */
1825                     if ($tagtype == 1
1826                         && in_array($tagname, $self_closing_tags)){
1827                         $tagtype = 3;
1828                     }
1829                     /**
1830                     * See if we should skip this tag and any content
1831                     * inside it.
1832                     */
1833                     if ($tagtype == 1 &&
1834                         in_array($tagname, $rm_tags_with_content)){
1835                         $skip_content = $tagname;
1836                     } else {
1837                         if (($rm_tags == false
1838                             && in_array($tagname, $tag_list)) ||
1839                             ($rm_tags == true &&
1840                             !in_array($tagname, $tag_list))){
1841                             $tagname = false;
1842                         } else {
1843                             /**
1844                             * Convert body into div.
1845                             */
1846                             if ($tagname == "body"){
1847                                 $tagname = "div";
1848                                 $attary = sq_body2div($attary, $mailbox,
1849                                                     $message, $id);
1850                             }
1851                             if ($tagtype == 1){
1852                                 if (isset($open_tags{$tagname})){
1853                                     $open_tags{$tagname}++;
1854                                 } else {
1855                                     $open_tags{$tagname}=1;
1856                                 }
1857                             }
1858                             /**
1859                             * This is where we run other checks.
1860                             */
1861                             if (is_array($attary) && sizeof($attary) > 0){
1862                                 $attary = sq_fixatts($tagname,
1863                                                     $attary,
1864                                                     $rm_attnames,
1865                                                     $bad_attvals,
1866                                                     $add_attr_to_tag,
1867                                                     $message,
1868                                                     $id,
1869                                                     $mailbox
1870                                                     );
1871                             }
1872                         }
1873                     }
1874                 }
1875             }
1876             if ($tagname != false && $skip_content == false){
1877                 $trusted .= sq_tagprint($tagname, $attary, $tagtype);
1878             }
1879         }
1880         $curpos = $gt+1;
1881     }
1882     $trusted .= substr($body, $curpos, strlen($body)-$curpos);
1883     if ($force_tag_closing == true){
1884         foreach ($open_tags as $tagname=>$opentimes){
1885             while ($opentimes > 0){
1886                 $trusted .= '</' . $tagname . '>';
1887                 $opentimes--;
1888             }
1889         }
1890         $trusted .= "\n";
1891     }
1892     $trusted .= "<!-- end sanitized html -->\n";
1893     return $trusted;
1894 }
1895
1896 /**
1897 * This is a wrapper function to call html sanitizing routines.
1898 *
1899 * @param  $body  the body of the message
1900 * @param  $id    the id of the message
1901 * @param  $message
1902 * @param  $mailbox
1903 * @param  boolean $take_mailto_links When TRUE, converts mailto: links
1904 *                                    into internal SM compose links
1905 *                                    (optional; default = TRUE)
1906 * @return        a string with html safe to display in the browser.
1907 */
1908 function magicHTML($body, $id, $message, $mailbox = 'INBOX', $take_mailto_links = true) {
1909
1910     require_once(SM_PATH . 'functions/url_parser.php');  // for $MailTo_PReg_Match
1911
1912     global $attachment_common_show_images, $view_unsafe_images,
1913         $has_unsafe_images;
1914
1915     /**
1916     * Don't display attached images in HTML mode.
1917     */
1918     $attachment_common_show_images = false;
1919     $tag_list = Array(
1920                     false,
1921                     "object",
1922                     "meta",
1923                     "html",
1924                     "head",
1925                     "base",
1926                     "link",
1927                     "frame",
1928                     "iframe",
1929                     "plaintext",
1930                     "marquee"
1931                     );
1932
1933     $rm_tags_with_content = Array(
1934                                 "script",
1935                                 "applet",
1936                                 "embed",
1937                                 "title",
1938                                 "frameset",
1939                                 "xml"
1940                                 );
1941
1942     $self_closing_tags =  Array(
1943                                 "img",
1944                                 "br",
1945                                 "hr",
1946                                 "input",
1947                                 "outbind"
1948                                 );
1949
1950     $force_tag_closing = true;
1951
1952     $rm_attnames = Array(
1953                         "/.*/" =>
1954                         Array(
1955                             "/target/i",
1956                             "/^on.*/i",
1957                             "/^dynsrc/i",
1958                             "/^data.*/i",
1959                             "/^lowsrc.*/i"
1960                             )
1961                         );
1962
1963     $secremoveimg = "../images/" . _("sec_remove_eng.png");
1964     $bad_attvals = Array(
1965         "/.*/" =>
1966             Array(
1967                 "/^src|background/i" =>
1968                     Array(
1969                         Array(
1970                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1971                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1972                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1973                                 ),
1974                         Array(
1975                                 "\\1$secremoveimg\\2",
1976                                 "\\1$secremoveimg\\2",
1977                                 "\\1$secremoveimg\\2",
1978                                 "\\1$secremoveimg\\2"
1979                                 )
1980                         ),
1981                 "/^href|action/i" =>
1982                     Array(
1983                         Array(
1984                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1985                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1986                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1987                                 ),
1988                         Array(
1989                                 "\\1#\\1",
1990                                 "\\1#\\1",
1991                                 "\\1#\\1",
1992                                 "\\1#\\1"
1993                                 )
1994                         ),
1995                 "/^style/i" =>
1996                     Array(
1997                         Array(
1998                                 "/expression/i",
1999                                 "/binding/i",
2000                                 "/behaviou*r/i",
2001                                 "/include-source/i",
2002                                 "/position\s*:\s*absolute/i",
2003                                 "/url\s*\(\s*([\'\"])\s*\S+script\s*:.*([\'\"])\s*\)/si",
2004                                 "/url\s*\(\s*([\'\"])\s*mocha\s*:.*([\'\"])\s*\)/si",
2005                                 "/url\s*\(\s*([\'\"])\s*about\s*:.*([\'\"])\s*\)/si",
2006                                 "/(.*)\s*:\s*url\s*\(\s*([\'\"]*)\s*\S+script\s*:.*([\'\"]*)\s*\)/si"
2007                             ),
2008                         Array(
2009                                 "idiocy",
2010                                 "idiocy",
2011                                 "idiocy",
2012                                 "idiocy",
2013                                 "",
2014                                 "url(\\1#\\1)",
2015                                 "url(\\1#\\1)",
2016                                 "url(\\1#\\1)",
2017                                 "url(\\1#\\1)",
2018                                 "\\1:url(\\2#\\3)"
2019                             )
2020                         )
2021                 )
2022         );
2023     if( !sqgetGlobalVar('view_unsafe_images', $view_unsafe_images, SQ_GET) ) {
2024         $view_unsafe_images = false;
2025     }
2026     if (!$view_unsafe_images){
2027         /**
2028         * Remove any references to http/https if view_unsafe_images set
2029         * to false.
2030         */
2031         array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[0],
2032                     '/^([\'\"])\s*https*:.*([\'\"])/si');
2033         array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[1],
2034                     "\\1$secremoveimg\\1");
2035         array_push($bad_attvals{'/.*/'}{'/^style/i'}[0],
2036                     '/url\(([\'\"])\s*https*:.*([\'\"])\)/si');
2037         array_push($bad_attvals{'/.*/'}{'/^style/i'}[1],
2038                     "url(\\1$secremoveimg\\1)");
2039     }
2040
2041     $add_attr_to_tag = Array(
2042         "/^a$/i" =>
2043             Array('target'=>'"_blank"',
2044                 'title'=>'"'._("This external link will open in a new window").'"'
2045             )
2046     );
2047     $trusted = sq_sanitize($body,
2048                         $tag_list,
2049                         $rm_tags_with_content,
2050                         $self_closing_tags,
2051                         $force_tag_closing,
2052                         $rm_attnames,
2053                         $bad_attvals,
2054                         $add_attr_to_tag,
2055                         $message,
2056                         $id,
2057                         $mailbox
2058                         );
2059     if (preg_match("|$secremoveimg|i", $trusted)){
2060         $has_unsafe_images = true;
2061     }
2062
2063
2064     // we want to parse mailto's in HTML output, change to SM compose links
2065     // this is a modified version of code from url_parser.php... but Marc is
2066     // right: we need a better filtering implementation; adding this randomly
2067     // here is not a great solution
2068     //
2069     if ($take_mailto_links) {
2070         // parseUrl($trusted);   // this even parses URLs inside of tags... too aggressive
2071         global $MailTo_PReg_Match;
2072         $MailTo_PReg_Match = '/mailto:' . substr($MailTo_PReg_Match, 1);
2073         if ((preg_match_all($MailTo_PReg_Match, $trusted, $regs)) && ($regs[0][0] != '')) {
2074             foreach ($regs[0] as $i => $mailto_before) {
2075                 $mailto_params = $regs[10][$i];
2076
2077                 // get rid of any tailing quote since we have to add send_to to the end
2078                 //
2079                 if (substr($mailto_before, strlen($mailto_before) - 1) == '"')
2080                     $mailto_before = substr($mailto_before, 0, strlen($mailto_before) - 1);
2081                 if (substr($mailto_params, strlen($mailto_params) - 1) == '"')
2082                     $mailto_params = substr($mailto_params, 0, strlen($mailto_params) - 1);
2083
2084                 if ($regs[1][$i]) {    //if there is an email addr before '?', we need to merge it with the params
2085                     $to = 'to=' . $regs[1][$i];
2086                     if (strpos($mailto_params, 'to=') > -1)    //already a 'to='
2087                         $mailto_params = str_replace('to=', $to . '%2C%20', $mailto_params);
2088                     else {
2089                         if ($mailto_params)    //already some params, append to them
2090                             $mailto_params .= '&amp;' . $to;
2091                         else
2092                             $mailto_params .= '?' . $to;
2093                     }
2094                 }
2095
2096                 $url_str = preg_replace(array('/to=/i', '/(?<!b)cc=/i', '/bcc=/i'), array('send_to=', 'send_to_cc=', 'send_to_bcc='), $mailto_params);
2097
2098                 // we'll already have target=_blank, no need to allow comp_in_new
2099                 // here (which would be a lot more work anyway)
2100                 //
2101                 global $compose_new_win;
2102                 $temp_comp_in_new = $compose_new_win;
2103                 $compose_new_win = 0;
2104                 $comp_uri = makeComposeLink('src/compose.php' . $url_str, $mailto_before);
2105                 $compose_new_win = $temp_comp_in_new;
2106
2107                 // remove <a href=" and anything after the next quote (we only
2108                 // need the uri, not the link HTML) in compose uri
2109                 //
2110                 $comp_uri = substr($comp_uri, 9);
2111                 $comp_uri = substr($comp_uri, 0, strpos($comp_uri, '"', 1));
2112                 $trusted = str_replace($mailto_before, $comp_uri, $trusted);
2113             }
2114         }
2115     }
2116
2117     return $trusted;
2118 }
2119
2120 /**
2121 * function SendDownloadHeaders - send file to the browser
2122 *
2123 * Original Source: SM core src/download.php
2124 * moved here to make it available to other code, and separate
2125 * front end from back end functionality.
2126 *
2127 * @param string $type0 first half of mime type
2128 * @param string $type1 second half of mime type
2129 * @param string $filename filename to tell the browser for downloaded file
2130 * @param boolean $force whether to force the download dialog to pop
2131 * @param optional integer $filesize send the Content-Header and length to the browser
2132 * @return void
2133 */
2134 function SendDownloadHeaders($type0, $type1, $filename, $force, $filesize=0) {
2135     global $languages, $squirrelmail_language;
2136     $isIE = $isIE6 = 0;
2137
2138     sqgetGlobalVar('HTTP_USER_AGENT', $HTTP_USER_AGENT, SQ_SERVER);
2139
2140     if (strstr($HTTP_USER_AGENT, 'compatible; MSIE ') !== false &&
2141         strstr($HTTP_USER_AGENT, 'Opera') === false) {
2142         $isIE = 1;
2143     }
2144
2145     if (strstr($HTTP_USER_AGENT, 'compatible; MSIE 6') !== false &&
2146         strstr($HTTP_USER_AGENT, 'Opera') === false) {
2147         $isIE6 = 1;
2148     }
2149
2150     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
2151         function_exists($languages[$squirrelmail_language]['XTRA_CODE'] . '_downloadfilename')) {
2152         $filename =
2153         call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_downloadfilename', $filename, $HTTP_USER_AGENT);
2154     } else {
2155         $filename = ereg_replace('[\\/:\*\?"<>\|;]', '_', str_replace('&nbsp;', ' ', $filename));
2156     }
2157
2158     // A Pox on Microsoft and it's Internet Explorer!
2159     //
2160     // IE has lots of bugs with file downloads.
2161     // It also has problems with SSL.  Both of these cause problems
2162     // for us in this function.
2163     //
2164     // See this article on Cache Control headers and SSL
2165     // http://support.microsoft.com/default.aspx?scid=kb;en-us;323308
2166     //
2167     // The best thing you can do for IE is to upgrade to the latest
2168     // version
2169     //set all the Cache Control Headers for IE
2170     if ($isIE) {
2171         $filename=rawurlencode($filename);
2172         header ("Pragma: public");
2173         header ("Cache-Control: no-store, max-age=0, no-cache, must-revalidate"); # HTTP/1.1
2174         header ("Cache-Control: post-check=0, pre-check=0", false);
2175         header ("Cache-control: private");
2176
2177         //set the inline header for IE, we'll add the attachment header later if we need it
2178         header ("Content-Disposition: inline; filename=$filename");
2179     }
2180
2181     if (!$force) {
2182         // Try to show in browser window
2183         header ("Content-Disposition: inline; filename=\"$filename\"");
2184         header ("Content-Type: $type0/$type1; name=\"$filename\"");
2185     } else {
2186         // Try to pop up the "save as" box
2187
2188         // IE makes this hard.  It pops up 2 save boxes, or none.
2189         // http://support.microsoft.com/support/kb/articles/Q238/5/88.ASP
2190         // http://support.microsoft.com/default.aspx?scid=kb;EN-US;260519
2191         // But, according to Microsoft, it is "RFC compliant but doesn't
2192         // take into account some deviations that allowed within the
2193         // specification."  Doesn't that mean RFC non-compliant?
2194         // http://support.microsoft.com/support/kb/articles/Q258/4/52.ASP
2195
2196         // all browsers need the application/octet-stream header for this
2197         header ("Content-Type: application/octet-stream; name=\"$filename\"");
2198
2199         // http://support.microsoft.com/support/kb/articles/Q182/3/15.asp
2200         // Do not have quotes around filename, but that applied to
2201         // "attachment"... does it apply to inline too?
2202         header ("Content-Disposition: attachment; filename=\"$filename\"");
2203
2204         if ($isIE && !$isIE6) {
2205             // This combination seems to work mostly.  IE 5.5 SP 1 has
2206             // known issues (see the Microsoft Knowledge Base)
2207
2208             // This works for most types, but doesn't work with Word files
2209             header ("Content-Type: application/download; name=\"$filename\"");
2210
2211             // These are spares, just in case.  :-)
2212             //header("Content-Type: $type0/$type1; name=\"$filename\"");
2213             //header("Content-Type: application/x-msdownload; name=\"$filename\"");
2214             //header("Content-Type: application/octet-stream; name=\"$filename\"");
2215         } else {
2216             // another application/octet-stream forces download for Netscape
2217             header ("Content-Type: application/octet-stream; name=\"$filename\"");
2218         }
2219     }
2220
2221     //send the content-length header if the calling function provides it
2222     if ($filesize > 0) {
2223         header("Content-Length: $filesize");
2224     }
2225
2226 }  // end fn SendDownloadHeaders
2227
2228 ?>