functions/mime.php

   1 <?php
   2
   3 /**
   4  * mime.php
   5  *
   6  * Copyright (c) 1999-2002 The SquirrelMail Project Team
   7  * Licensed under the GNU GPL. For full terms see the file COPYING.
   8  *
   9  * This contains the functions necessary to detect and decode MIME
  10  * messages.
  11  *
  12  * $Id$
  13  */
  14
  15 require_once(SM_PATH . 'functions/imap.php');
  16 require_once(SM_PATH . 'functions/attachment_common.php');
  17
  18 /* --------------------------------------------------------------------------------- */
  19 /* MIME DECODING                                                                     */
  20 /* --------------------------------------------------------------------------------- */
  21
  22 /* This function gets the structure of a message and stores it in the "message" class.
  23  * It will return this object for use with all relevant header information and
  24  * fully parsed into the standard "message" object format.
  25  */
  26
  27 function mime_structure ($bodystructure, $flags=array()) {
  28
  29     /* Isolate the body structure and remove beginning and end parenthesis. */
  30     $read = trim(substr ($bodystructure, strpos(strtolower($bodystructure), 'bodystructure') + 13));
  31     $read = trim(substr ($read, 0, -1));
  32     $msg =& new Message();
  33     $res  = $msg->parseStructure($read);
  34     $msg  = $res[0];
  35     if (!is_object($msg)) {
  36         include_once(SM_PATH . 'functions/display_messages.php');
  37         global $color, $mailbox;
  38         displayPageHeader( $color, urldecode($mailbox) );
  39         echo "<BODY TEXT=\"$color[8]\" BGCOLOR=\"$color[4]\" LINK=\"$color[7]\" VLINK=\"$color[7]\" ALINK=\"$color[7]\">\n\n" .
  40          '<CENTER>';
  41         $errormessage  = _("SquirrelMail could not decode the bodystructure of the message");
  42         $errormessage .= '<BR>'._("the provided bodystructure by your imap-server").':<BR><BR>';
  43         $errormessage .= '<table><tr><td>' . htmlspecialchars($read) . '</td></tr></table>';
  44         plain_error_message( $errormessage, $color );
  45         echo '</body></html>';
  46         exit;
  47     }
  48     $msg->setEnt('0');
  49     if (count($flags)) {
  50         foreach ($flags as $flag) {
  51             $char = strtoupper($flag{1});
  52             switch ($char) {
  53                 case 'S':
  54                     if (strtolower($flag) == '\\seen') {
  55                         $msg->is_seen = true;
  56                     }
  57                     break;
  58                 case 'A':
  59                     if (strtolower($flag) == '\\answered') {
  60                         $msg->is_answered = true;
  61                     }
  62                     break;
  63                 case 'D':
  64                     if (strtolower($flag) == '\\deleted') {
  65                         $msg->is_deleted = true;
  66                     }
  67                     break;
  68                 case 'F':
  69                     if (strtolower($flag) == '\\flagged') {
  70                         $msg->is_flagged = true;
  71                     }
  72                     break;
  73                 case 'M':
  74                     if (strtolower($flag) == '$mdnsent') {
  75                         $msg->is_mdnsent = true;
  76                     }
  77                     break;
  78                 default:
  79                     break;
  80             }
  81         }
  82     }
  83     //    listEntities($msg);
  84     return $msg;
  85 }
  86
  87 /* This starts the parsing of a particular structure.  It is called recursively,
  88  * so it can be passed different structures.  It returns an object of type
  89  * $message.
  90  * First, it checks to see if it is a multipart message.  If it is, then it
  91  * handles that as it sees is necessary.  If it is just a regular entity,
  92  * then it parses it and adds the necessary header information (by calling out
  93  * to mime_get_elements()
  94  */
  95
  96 function mime_fetch_body($imap_stream, $id, $ent_id) {
  97     global $uid_support;
  98     /* Do a bit of error correction.  If we couldn't find the entity id, just guess
  99      * that it is the first one.  That is usually the case anyway.
 100      */
 101     if (!$ent_id) {
 102         $ent_id = 1;
 103     }
 104     $cmd = "FETCH $id BODY[$ent_id]";
 105
 106     $data = sqimap_run_command ($imap_stream, $cmd, true, $response, $message, $uid_support);
 107     do {
 108         $topline = trim(array_shift($data));
 109     } while($topline && ($topline[0] == '*') && !preg_match('/\* [0-9]+ FETCH.*/i', $topline)) ;
 110
 111     $wholemessage = implode('', $data);
 112     if (ereg('\\{([^\\}]*)\\}', $topline, $regs)) {
 113         $ret = substr($wholemessage, 0, $regs[1]);
 114         /* There is some information in the content info header that could be important
 115          * in order to parse html messages. Let's get them here.
 116          */
 117         if ($ret{0} == '<') {
 118             $data = sqimap_run_command ($imap_stream, "FETCH $id BODY[$ent_id.MIME]", true, $response, $message, $uid_support);
 119         }
 120     } else if (ereg('"([^"]*)"', $topline, $regs)) {
 121         $ret = $regs[1];
 122     } else {
 123         global $where, $what, $mailbox, $passed_id, $startMessage;
 124         $par = 'mailbox=' . urlencode($mailbox) . '&amp;passed_id=' . $passed_id;
 125         if (isset($where) && isset($what)) {
 126             $par .= '&amp;where=' . urlencode($where) . '&amp;what=' . urlencode($what);
 127         } else {
 128             $par .= '&amp;startMessage=' . $startMessage . '&amp;show_more=0';
 129         }
 130         $par .= '&amp;response=' . urlencode($response) .
 131                 '&amp;message='  . urlencode($message)  .
 132                 '&amp;topline='  . urlencode($topline);
 133
 134         echo   '<tt><br>' .
 135                '<table width="80%"><tr>' .
 136                '<tr><td colspan=2>' .
 137                _("Body retrieval error. The reason for this is most probably that the message is malformed.") .
 138                '</td></tr>' .
 139                '<tr><td><b>' . _("Command:") . "</td><td>$cmd</td></tr>" .
 140                '<tr><td><b>' . _("Response:") . "</td><td>$response</td></tr>" .
 141                '<tr><td><b>' . _("Message:") . "</td><td>$message</td></tr>" .
 142                '<tr><td><b>' . _("FETCH line:") . "</td><td>$topline</td></tr>" .
 143                "</table><BR></tt></font><hr>";
 144
 145         $data = sqimap_run_command ($imap_stream, "FETCH $passed_id BODY[]", true, $response, $message, $uid_support);
 146         array_shift($data);
 147         $wholemessage = implode('', $data);
 148
 149         $ret = $wholemessage;
 150     }
 151     return $ret;
 152 }
 153
 154 function mime_print_body_lines ($imap_stream, $id, $ent_id, $encoding) {
 155     global $uid_support;
 156     /* Do a bit of error correction.  If we couldn't find the entity id, just guess
 157      * that it is the first one.  That is usually the case anyway.
 158      */
 159     if (!$ent_id) {
 160         $ent_id = 1;
 161     }
 162     $sid = sqimap_session_id($uid_support);
 163     /* Don't kill the connection if the browser is over a dialup
 164      * and it would take over 30 seconds to download it.
 165      * Don´t call set_time_limit in safe mode.
 166      */
 167
 168     if (!ini_get('safe_mode')) {
 169         set_time_limit(0);
 170     }
 171     if ($uid_support) {
 172        $sid_s = substr($sid,0,strpos($sid, ' '));
 173     } else {
 174        $sid_s = $sid;
 175     }
 176
 177     $body = mime_fetch_body ($imap_stream, $id, $ent_id);
 178     echo decodeBody($body, $encoding);
 179     return;
 180 /*
 181     fputs ($imap_stream, "$sid FETCH $id BODY[$ent_id]\r\n");
 182     $cnt = 0;
 183     $continue = true;
 184     $read = fgets ($imap_stream,8192);
 185
 186
 187     // This could be bad -- if the section has sqimap_session_id() . ' OK'
 188     // or similar, it will kill the download.
 189     while (!ereg("^".$sid_s." (OK|BAD|NO)(.*)$", $read, $regs)) {
 190         if (trim($read) == ')==') {
 191             $read1 = $read;
 192             $read = fgets ($imap_stream,4096);
 193             if (ereg("^".$sid." (OK|BAD|NO)(.*)$", $read, $regs)) {
 194                 return;
 195             } else {
 196                 echo decodeBody($read1, $encoding) .
 197                      decodeBody($read, $encoding);
 198             }
 199         } else if ($cnt) {
 200             echo decodeBody($read, $encoding);
 201         }
 202         $read = fgets ($imap_stream,4096);
 203         $cnt++;
 204 //      break;
 205     }
 206 */
 207 }
 208
 209 /* -[ END MIME DECODING ]----------------------------------------------------------- */
 210
 211 /* This is here for debugging purposes.  It will print out a list
 212  * of all the entity IDs that are in the $message object.
 213  */
 214 function listEntities ($message) {
 215     if ($message) {
 216         echo "<tt>" . $message->entity_id . ' : ' . $message->type0 . '/' . $message->type1 . ' parent = '. $message->parent->entity_id. '<br>';
 217         for ($i = 0; isset($message->entities[$i]); $i++) {
 218             echo "$i : ";
 219             $msg = listEntities($message->entities[$i]);
 220
 221             if ($msg) {
 222                 echo "return: ";
 223                 return $msg;
 224             }
 225         }
 226     }
 227 }
 228
 229 function getPriorityStr($priority) {
 230     $priority_level = substr($priority,0,1);
 231
 232     switch($priority_level) {
 233         /* Check for a higher then normal priority. */
 234         case '1':
 235         case '2':
 236             $priority_string = _("High");
 237             break;
 238
 239         /* Check for a lower then normal priority. */
 240         case '4':
 241         case '5':
 242             $priority_string = _("Low");
 243             break;
 244
 245         /* Check for a normal priority. */
 246         case '3':
 247         default:
 248             $priority_level = '3';
 249             $priority_string = _("Normal");
 250             break;
 251
 252     }
 253     return $priority_string;
 254 }
 255
 256 /* returns a $message object for a particular entity id */
 257 function getEntity ($message, $ent_id) {
 258     return $message->getEntity($ent_id);
 259 }
 260
 261 /* translateText
 262  * Extracted from strings.php 23/03/2002
 263  */
 264
 265 function translateText(&$body, $wrap_at, $charset) {
 266     global $where, $what;   /* from searching */
 267     global $color;          /* color theme */
 268
 269     require_once(SM_PATH . 'functions/url_parser.php');
 270
 271     $body_ary = explode("\n", $body);
 272     for ($i=0; $i < count($body_ary); $i++) {
 273         $line = $body_ary[$i];
 274         if (strlen($line) - 2 >= $wrap_at) {
 275             sqWordWrap($line, $wrap_at);
 276         }
 277         $line = charset_decode($charset, $line);
 278         $line = str_replace("\t", '        ', $line);
 279
 280         parseUrl ($line);
 281
 282         $quotes = 0;
 283         $pos = 0;
 284         $j = strlen($line);
 285
 286         while ($pos < $j) {
 287             if ($line[$pos] == ' ') {
 288                 $pos++;
 289             } else if (strpos($line, '&gt;', $pos) === $pos) {
 290                 $pos += 4;
 291                 $quotes++;
 292             } else {
 293                 break;
 294             }
 295         }
 296
 297         if ($quotes > 1) {
 298             if (!isset($color[14])) {
 299                 $color[14] = '#FF0000';
 300             }
 301             $line = '<FONT COLOR="' . $color[14] . '">' . $line . '</FONT>';
 302         } elseif ($quotes) {
 303             if (!isset($color[13])) {
 304                 $color[13] = '#800000';
 305             }
 306             $line = '<FONT COLOR="' . $color[13] . '">' . $line . '</FONT>';
 307         }
 308
 309         $body_ary[$i] = $line;
 310     }
 311     $body = '<pre>' . implode("\n", $body_ary) . '</pre>';
 312 }
 313
 314
 315 /* This returns a parsed string called $body. That string can then
 316  * be displayed as the actual message in the HTML. It contains
 317  * everything needed, including HTML Tags, Attachments at the
 318  * bottom, etc.
 319  */
 320 function formatBody($imap_stream, $message, $color, $wrap_at, $ent_num, $id, $mailbox='INBOX') {
 321     /* This if statement checks for the entity to show as the
 322      * primary message. To add more of them, just put them in the
 323      * order that is their priority.
 324      */
 325     global $startMessage, $username, $key, $imapServerAddress, $imapPort,
 326            $show_html_default, $has_unsafe_images, $sort;
 327
 328     if ( (float)substr(PHP_VERSION,0,3) < 4.1 ) {
 329         global $_GET;
 330     }
 331     if(isset($_GET['view_unsafe_images'])) {
 332         $view_unsafe_images = $_GET['view_unsafe_images'];
 333     }
 334
 335     $has_unsafe_images= 0;
 336     $body = '';
 337     $urlmailbox = urlencode($mailbox);
 338     $body_message = getEntity($message, $ent_num);
 339     if (($body_message->header->type0 == 'text') ||
 340         ($body_message->header->type0 == 'rfc822')) {
 341         $body = mime_fetch_body ($imap_stream, $id, $ent_num);
 342         $body = decodeBody($body, $body_message->header->encoding);
 343         $hookResults = do_hook("message_body", $body);
 344         $body = $hookResults[1];
 345
 346         /* If there are other types that shouldn't be formatted, add
 347          * them here.
 348          */
 349
 350         if ($body_message->header->type1 == 'html') {
 351             if ($show_html_default <> 1) {
 352                 $entity_conv = array('&nbsp;' => ' ',
 353                                      '<p>'    => "\n",
 354                                      '<br>'   => "\n",
 355                                      '<P>'    => "\n",
 356                                      '<BR>'   => "\n",
 357                                      '&gt;'   => '>',
 358                                      '&lt;'   => '<');
 359                 $body = strtr($body, $entity_conv);
 360                 $body = strip_tags($body);
 361                 $body = trim($body);
 362                 translateText($body, $wrap_at,
 363                               $body_message->header->getParameter('charset'));
 364             } else {
 365                 $body = magicHTML($body, $id, $message, $mailbox);
 366             }
 367         } else {
 368             translateText($body, $wrap_at,
 369                           $body_message->header->getParameter('charset'));
 370         }
 371
 372         if ($has_unsafe_images) {
 373             if ($view_unsafe_images) {
 374                 $untext = '">' . _("Hide Unsafe Images");
 375             } else {
 376                 $untext = '&amp;view_unsafe_images=1">' . _("View Unsafe Images");
 377             }
 378             $body .= '<center><small><a href="read_body.php?passed_id=' . $id .
 379                      '&amp;passed_ent_id=' . $message->entity_id . '&amp;mailbox=' . $urlmailbox .
 380                      '&amp;sort=' . $sort . '&amp;startMessage=' . $startMessage . '&amp;show_more=0' .
 381                      $untext . '</a></small></center><br>' . "\n";
 382         }
 383     }
 384     return $body;
 385 }
 386
 387
 388 function formatAttachments($message, $exclude_id, $mailbox, $id) {
 389     global $where, $what, $startMessage, $color;
 390     static $ShownHTML = 0;
 391
 392     $att_ar = $message->getAttachments($exclude_id);
 393
 394     if (!count($att_ar)) return '';
 395
 396     $attachments = '';
 397
 398     $urlMailbox = urlencode($mailbox);
 399
 400     foreach ($att_ar as $att) {
 401         $ent = urldecode($att->entity_id);
 402         $header = $att->header;
 403         $type0 = strtolower($header->type0);
 404         $type1 = strtolower($header->type1);
 405         $name = '';
 406         $links['download link']['text'] = _("download");
 407         $links['download link']['href'] =
 408                 "../src/download.php?absolute_dl=true&amp;passed_id=$id&amp;mailbox=$urlMailbox&amp;ent_id=$ent";
 409         $ImageURL = '';
 410         if ($type0 =='message' && $type1 == 'rfc822') {
 411             $default_page = '../src/read_body.php';
 412             $rfc822_header = $att->rfc822_header;
 413             $filename = decodeHeader($rfc822_header->subject);
 414
 415             $from_o = $rfc822_header->from;
 416             if (is_object($from_o)) {
 417                 $from_name = $from_o->getAddress(false);
 418             } else {
 419                 $from_name = _("Unknown sender");
 420             }
 421             $from_name = decodeHeader(htmlspecialchars($from_name));
 422             $description = $from_name;
 423         } else {
 424             $default_page = '../src/download.php';
 425             if (is_object($header->disposition)) {
 426                 $filename = decodeHeader($header->disposition->getProperty('filename'));
 427                 if (trim($filename) == '') {
 428                     $name = decodeHeader($header->disposition->getProperty('name'));
 429                     if (trim($name) == '') {
 430                         if (trim( $header->id ) == '') {
 431                             $filename = 'untitled-[' . $ent . ']' ;
 432                         } else {
 433                             $filename = 'cid: ' . $header->id;
 434                         }
 435                     } else {
 436                         $filename = $name;
 437                     }
 438                 }
 439             } else {
 440                 if (trim( $header->id ) == '') {
 441                     $filename = 'untitled-[' . $ent . ']' ;
 442                 } else {
 443                     $filename = 'cid: ' . $header->id;
 444                 }
 445             }
 446
 447             if ($header->description) {
 448                 $description = htmlspecialchars($header->description);
 449             } else {
 450                 $description = '';
 451             }
 452         }
 453
 454         $display_filename = $filename;
 455         if (isset($passed_ent_id)) {
 456             $passed_ent_id_link = '&amp;passed_ent_id='.$passed_ent_id;
 457         } else {
 458             $passed_ent_id_link = '';
 459         }
 460         $defaultlink = $default_page . "?startMessage=$startMessage"
 461                      . "&amp;passed_id=$id&amp;mailbox=$urlMailbox"
 462                      . '&amp;ent_id='.$ent.$passed_ent_id_link;
 463         if ($where && $what) {
 464            $defaultlink .= '&amp;where='. urlencode($where).'&amp;what='.urlencode($what);
 465         }
 466         /* This executes the attachment hook with a specific MIME-type.
 467          * If that doesn't have results, it tries if there's a rule
 468          * for a more generic type.
 469          */
 470         $hookresults = do_hook("attachment $type0/$type1", $links,
 471                                $startMessage, $id, $urlMailbox, $ent, $defaultlink,
 472                                $display_filename, $where, $what);
 473         if(count($hookresults[1]) <= 1) {
 474             $hookresults = do_hook("attachment $type0/*", $links,
 475                                    $startMessage, $id, $urlMailbox, $ent, $defaultlink,
 476                                    $display_filename, $where, $what);
 477         }
 478
 479         $links = $hookresults[1];
 480         $defaultlink = $hookresults[6];
 481
 482         $attachments .= '<TR><TD>' .
 483                         "<A HREF=\"$defaultlink\">$display_filename</A>&nbsp;</TD>" .
 484                         '<TD><SMALL><b>' . show_readable_size($header->size) .
 485                         '</b>&nbsp;&nbsp;</small></TD>' .
 486                         "<TD><SMALL>[ $type0/$type1 ]&nbsp;</SMALL></TD>" .
 487                         '<TD><SMALL>';
 488         $attachments .= '<b>' . $description . '</b>';
 489         $attachments .= '</SMALL></TD><TD><SMALL>&nbsp;';
 490
 491         $skipspaces = 1;
 492         foreach ($links as $val) {
 493             if ($skipspaces) {
 494                 $skipspaces = 0;
 495             } else {
 496                 $attachments .= '&nbsp;&nbsp;|&nbsp;&nbsp;';
 497             }
 498             $attachments .= '<a href="' . $val['href'] . '">' .  $val['text'] . '</a>';
 499         }
 500         unset($links);
 501         $attachments .= "</TD></TR>\n";
 502     }
 503     return $attachments;
 504 }
 505
 506 /* This function decodes the body depending on the encoding type. */
 507 function decodeBody($body, $encoding) {
 508     global $languages, $squirrelmail_language;
 509     global $show_html_default;
 510
 511     $body = str_replace("\r\n", "\n", $body);
 512     $encoding = strtolower($encoding);
 513
 514     if ($encoding == 'quoted-printable' ||
 515         $encoding == 'quoted_printable') {
 516         $body = quoted_printable_decode($body);
 517
 518         while (ereg("=\n", $body)) {
 519             $body = ereg_replace ("=\n", '', $body);
 520         }
 521
 522     } else if ($encoding == 'base64') {
 523         $body = base64_decode($body);
 524     }
 525
 526     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 527         function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
 528         $body = $languages[$squirrelmail_language]['XTRA_CODE']('decode', $body);
 529     }
 530
 531     // All other encodings are returned raw.
 532     return $body;
 533 }
 534
 535 /*
 536  * This functions decode strings that is encoded according to
 537  * RFC1522 (MIME Part Two: Message Header Extensions for Non-ASCII Text).
 538  * Patched by Christian Schmidt <christian@ostenfeld.dk>  23/03/2002
 539  */
 540 function decodeHeader ($string, $utfencode=true) {
 541     global $languages, $squirrelmail_language;
 542     if (is_array($string)) {
 543         $string = implode("\n", $string);
 544     }
 545
 546     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 547         function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
 548         $string = $languages[$squirrelmail_language]['XTRA_CODE']('decodeheader', $string);
 549     }
 550
 551     $i = 0;
 552     while (preg_match('/^(.{' . $i . '})(.*)=\?([^?]*)\?(Q|B)\?([^?]*)\?=/Ui',
 553                       $string, $res)) {
 554         $prefix = $res[1];
 555         /* Ignore white-space between consecutive encoded-words. */
 556         if (strspn($res[2], " \t") != strlen($res[2])) {
 557             $prefix .= $res[2];
 558         }
 559
 560         if (ucfirst($res[4]) == 'B') {
 561             $replace = base64_decode($res[5]);
 562         } else {
 563             $replace = str_replace('_', ' ', $res[5]);
 564             $replace = preg_replace('/=([0-9a-f]{2})/ie', 'chr(hexdec("\1"))',
 565                                     $replace);
 566             /* Only encode into entities by default. Some places
 567              * don't need the encoding, like the compose form.
 568              */
 569             if ($utfencode) {
 570                 $replace = charset_decode($res[3], $replace);
 571             }
 572         }
 573         $string = $prefix . $replace . substr($string, strlen($res[0]));
 574         $i = strlen($prefix) + strlen($replace);
 575     }
 576     return $string;
 577 }
 578
 579 /*
 580  * Encode a string according to RFC 1522 for use in headers if it
 581  * contains 8-bit characters or anything that looks like it should
 582  * be encoded.
 583  */
 584 function encodeHeader ($string) {
 585     global $default_charset, $languages, $squirrelmail_language;
 586
 587     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 588         function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
 589         return  $languages[$squirrelmail_language]['XTRA_CODE']('encodeheader', $string);
 590     }
 591
 592     // Encode only if the string contains 8-bit characters or =?
 593     $j = strlen($string);
 594     $l = strstr($string, '=?');         // Must be encoded ?
 595     $ret = '';
 596     for($i = 0; $i < $j; ++$i) {
 597         switch($string{$i}) {
 598             case '=':
 599                 $ret .= '=3D';
 600                 break;
 601             case '?':
 602                 $ret .= '=3F';
 603                 break;
 604             case '_':
 605                 $ret .= '=5F';
 606                 break;
 607             case ' ':
 608                 $ret .= '_';
 609                 break;
 610             default:
 611                 $k = ord($string{$i});
 612                 if ($k > 126) {
 613                     $ret .= sprintf("=%02X", $k);
 614                     $l = TRUE;
 615                 } else {
 616                     $ret .= $string{$i};
 617                 }
 618                 break;
 619         }
 620     }
 621
 622     if ($l) {
 623         $string = "=?$default_charset?Q?$ret?=";
 624     }
 625
 626     return $string;
 627 }
 628
 629 /* This function trys to locate the entity_id of a specific mime element */
 630 function find_ent_id($id, $message) {
 631     for ($i = 0, $ret = ''; $ret == '' && $i < count($message->entities); $i++) {
 632         if ($message->entities[$i]->header->type0 == 'multipart')  {
 633             $ret = find_ent_id($id, $message->entities[$i]);
 634         } else {
 635             if (strcasecmp($message->entities[$i]->header->id, $id) == 0) {
 636 //                if (sq_check_save_extension($message->entities[$i])) {
 637                     return $message->entities[$i]->entity_id;
 638 //                }
 639             }
 640         }
 641     }
 642     return $ret;
 643 }
 644
 645 function sq_check_save_extension($message) {
 646     $filename = $message->getFilename();
 647     $ext = substr($filename, strrpos($filename,'.')+1);
 648     $save_extensions = array('jpg','jpeg','gif','png','bmp');
 649     return in_array($ext, $save_extensions);
 650 }
 651
 652
 653 /**
 654  ** HTMLFILTER ROUTINES
 655  */
 656
 657 /**
 658  * This function returns the final tag out of the tag name, an array
 659  * of attributes, and the type of the tag. This function is called by
 660  * sq_sanitize internally.
 661  *
 662  * @param  $tagname  the name of the tag.
 663  * @param  $attary   the array of attributes and their values
 664  * @param  $tagtype  The type of the tag (see in comments).
 665  * @return           a string with the final tag representation.
 666  */
 667 function sq_tagprint($tagname, $attary, $tagtype){
 668     $me = 'sq_tagprint';
 669
 670     if ($tagtype == 2){
 671         $fulltag = '</' . $tagname . '>';
 672     } else {
 673         $fulltag = '<' . $tagname;
 674         if (is_array($attary) && sizeof($attary)){
 675             $atts = Array();
 676             while (list($attname, $attvalue) = each($attary)){
 677                 array_push($atts, "$attname=$attvalue");
 678             }
 679             $fulltag .= ' ' . join(" ", $atts);
 680         }
 681         if ($tagtype == 3){
 682             $fulltag .= ' /';
 683         }
 684         $fulltag .= '>';
 685     }
 686     return $fulltag;
 687 }
 688
 689 /**
 690  * A small helper function to use with array_walk. Modifies a by-ref
 691  * value and makes it lowercase.
 692  *
 693  * @param  $val a value passed by-ref.
 694  * @return      void since it modifies a by-ref value.
 695  */
 696 function sq_casenormalize(&$val){
 697     $val = strtolower($val);
 698 }
 699
 700 /**
 701  * This function skips any whitespace from the current position within
 702  * a string and to the next non-whitespace value.
 703  *
 704  * @param  $body   the string
 705  * @param  $offset the offset within the string where we should start
 706  *                 looking for the next non-whitespace character.
 707  * @return         the location within the $body where the next
 708  *                 non-whitespace char is located.
 709  */
 710 function sq_skipspace($body, $offset){
 711     $me = 'sq_skipspace';
 712     preg_match('/^(\s*)/s', substr($body, $offset), $matches);
 713     if (sizeof($matches{1})){
 714         $count = strlen($matches{1});
 715         $offset += $count;
 716     }
 717     return $offset;
 718 }
 719
 720 /**
 721  * This function looks for the next character within a string.  It's
 722  * really just a glorified "strpos", except it catches if failures
 723  * nicely.
 724  *
 725  * @param  $body   The string to look for needle in.
 726  * @param  $offset Start looking from this position.
 727  * @param  $needle The character/string to look for.
 728  * @return         location of the next occurance of the needle, or
 729  *                 strlen($body) if needle wasn't found.
 730  */
 731 function sq_findnxstr($body, $offset, $needle){
 732     $me  = 'sq_findnxstr';
 733     $pos = strpos($body, $needle, $offset);
 734     if ($pos === FALSE){
 735         $pos = strlen($body);
 736     }
 737     return $pos;
 738 }
 739
 740 /**
 741  * This function takes a PCRE-style regexp and tries to match it
 742  * within the string.
 743  *
 744  * @param  $body   The string to look for needle in.
 745  * @param  $offset Start looking from here.
 746  * @param  $reg    A PCRE-style regex to match.
 747  * @return         Returns a false if no matches found, or an array
 748  *                 with the following members:
 749  *                 - integer with the location of the match within $body
 750  *                 - string with whatever content between offset and the match
 751  *                 - string with whatever it is we matched
 752  */
 753 function sq_findnxreg($body, $offset, $reg){
 754     $me = 'sq_findnxreg';
 755     $matches = Array();
 756     $retarr = Array();
 757     preg_match("%^(.*?)($reg)%s", substr($body, $offset), $matches);
 758     if (!$matches{0}){
 759         $retarr = false;
 760     } else {
 761         $retarr{0} = $offset + strlen($matches{1});
 762         $retarr{1} = $matches{1};
 763         $retarr{2} = $matches{2};
 764     }
 765     return $retarr;
 766 }
 767
 768 /**
 769  * This function looks for the next tag.
 770  *
 771  * @param  $body   String where to look for the next tag.
 772  * @param  $offset Start looking from here.
 773  * @return         false if no more tags exist in the body, or
 774  *                 an array with the following members:
 775  *                 - string with the name of the tag
 776  *                 - array with attributes and their values
 777  *                 - integer with tag type (1, 2, or 3)
 778  *                 - integer where the tag starts (starting "<")
 779  *                 - integer where the tag ends (ending ">")
 780  *                 first three members will be false, if the tag is invalid.
 781  */
 782 function sq_getnxtag($body, $offset){
 783     $me = 'sq_getnxtag';
 784     if ($offset > strlen($body)){
 785         return false;
 786     }
 787     $lt = sq_findnxstr($body, $offset, "<");
 788     if ($lt == strlen($body)){
 789         return false;
 790     }
 791     /**
 792      * We are here:
 793      * blah blah <tag attribute="value">
 794      * \---------^
 795      */
 796     $pos = sq_skipspace($body, $lt+1);
 797     if ($pos >= strlen($body)){
 798         return Array(false, false, false, $lt, strlen($body));
 799     }
 800     /**
 801      * There are 3 kinds of tags:
 802      * 1. Opening tag, e.g.:
 803      *    <a href="blah">
 804      * 2. Closing tag, e.g.:
 805      *    </a>
 806      * 3. XHTML-style content-less tag, e.g.:
 807      *    <img src="blah"/>
 808      */
 809     $tagtype = false;
 810     switch (substr($body, $pos, 1)){
 811         case '/':
 812             $tagtype = 2;
 813             $pos++;
 814             break;
 815         case '!':
 816             /**
 817              * A comment or an SGML declaration.
 818              */
 819             if (substr($body, $pos+1, 2) == "--"){
 820                 $gt = strpos($body, "-->", $pos);
 821                 if ($gt === false){
 822                     $gt = strlen($body);
 823                 } else {
 824                     $gt += 2;
 825                 }
 826                 return Array(false, false, false, $lt, $gt);
 827             } else {
 828                 $gt = sq_findnxstr($body, $pos, ">");
 829                 return Array(false, false, false, $lt, $gt);
 830             }
 831             break;
 832         default:
 833             /**
 834              * Assume tagtype 1 for now. If it's type 3, we'll switch values
 835              * later.
 836              */
 837             $tagtype = 1;
 838             break;
 839     }
 840
 841     $tag_start = $pos;
 842     $tagname = '';
 843     /**
 844      * Look for next [\W-_], which will indicate the end of the tag name.
 845      */
 846     $regary = sq_findnxreg($body, $pos, "[^\w\-_]");
 847     if ($regary == false){
 848         return Array(false, false, false, $lt, strlen($body));
 849     }
 850     list($pos, $tagname, $match) = $regary;
 851     $tagname = strtolower($tagname);
 852
 853     /**
 854      * $match can be either of these:
 855      * '>'  indicating the end of the tag entirely.
 856      * '\s' indicating the end of the tag name.
 857      * '/'  indicating that this is type-3 xhtml tag.
 858      *
 859      * Whatever else we find there indicates an invalid tag.
 860      */
 861     switch ($match){
 862         case '/':
 863             /**
 864              * This is an xhtml-style tag with a closing / at the
 865              * end, like so: <img src="blah"/>. Check if it's followed
 866              * by the closing bracket. If not, then this tag is invalid
 867              */
 868             if (substr($body, $pos, 2) == "/>"){
 869                 $pos++;
 870                 $tagtype = 3;
 871             } else {
 872                 $gt = sq_findnxstr($body, $pos, ">");
 873                 $retary = Array(false, false, false, $lt, $gt);
 874                 return $retary;
 875             }
 876         case '>':
 877             return Array($tagname, false, $tagtype, $lt, $pos);
 878             break;
 879         default:
 880             /**
 881              * Check if it's whitespace
 882              */
 883             if (!preg_match('/\s/', $match)){
 884                 /**
 885                  * This is an invalid tag! Look for the next closing ">".
 886                  */
 887                 $gt = sq_findnxstr($body, $offset, ">");
 888                 return Array(false, false, false, $lt, $gt);
 889             }
 890             break;
 891     }
 892
 893     /**
 894      * At this point we're here:
 895      * <tagname  attribute='blah'>
 896      * \-------^
 897      *
 898      * At this point we loop in order to find all attributes.
 899      */
 900     $attname = '';
 901     $atttype = false;
 902     $attary = Array();
 903
 904     while ($pos <= strlen($body)){
 905         $pos = sq_skipspace($body, $pos);
 906         if ($pos == strlen($body)){
 907             /**
 908              * Non-closed tag.
 909              */
 910             return Array(false, false, false, $lt, $pos);
 911         }
 912         /**
 913          * See if we arrived at a ">" or "/>", which means that we reached
 914          * the end of the tag.
 915          */
 916         $matches = Array();
 917         if (preg_match("%^(\s*)(>|/>)%s", substr($body, $pos), $matches)) {
 918             /**
 919              * Yep. So we did.
 920              */
 921             $pos += strlen($matches{1});
 922             if ($matches{2} == "/>"){
 923                 $tagtype = 3;
 924                 $pos++;
 925             }
 926             return Array($tagname, $attary, $tagtype, $lt, $pos);
 927         }
 928
 929         /**
 930          * There are several types of attributes, with optional
 931          * [:space:] between members.
 932          * Type 1:
 933          *   attrname[:space:]=[:space:]'CDATA'
 934          * Type 2:
 935          *   attrname[:space:]=[:space:]"CDATA"
 936          * Type 3:
 937          *   attr[:space:]=[:space:]CDATA
 938          * Type 4:
 939          *   attrname
 940          *
 941          * We leave types 1 and 2 the same, type 3 we check for
 942          * '"' and convert to "&quot" if needed, then wrap in
 943          * double quotes. Type 4 we convert into:
 944          * attrname="yes".
 945          */
 946         $regary = sq_findnxreg($body, $pos, "[^\w\-_]");
 947         if ($regary == false){
 948             /**
 949              * Looks like body ended before the end of tag.
 950              */
 951             return Array(false, false, false, $lt, strlen($body));
 952         }
 953         list($pos, $attname, $match) = $regary;
 954         $attname = strtolower($attname);
 955         /**
 956          * We arrived at the end of attribute name. Several things possible
 957          * here:
 958          * '>'  means the end of the tag and this is attribute type 4
 959          * '/'  if followed by '>' means the same thing as above
 960          * '\s' means a lot of things -- look what it's followed by.
 961          *      anything else means the attribute is invalid.
 962          */
 963         switch($match){
 964             case '/':
 965                 /**
 966                  * This is an xhtml-style tag with a closing / at the
 967                  * end, like so: <img src="blah"/>. Check if it's followed
 968                  * by the closing bracket. If not, then this tag is invalid
 969                  */
 970                 if (substr($body, $pos, 2) == "/>"){
 971                     $pos++;
 972                     $tagtype = 3;
 973                 } else {
 974                     $gt = sq_findnxstr($body, $pos, ">");
 975                     $retary = Array(false, false, false, $lt, $gt);
 976                     return $retary;
 977                 }
 978             case '>':
 979                 $attary{$attname} = '"yes"';
 980                 return Array($tagname, $attary, $tagtype, $lt, $pos);
 981                 break;
 982             default:
 983                 /**
 984                  * Skip whitespace and see what we arrive at.
 985                  */
 986                 $pos = sq_skipspace($body, $pos);
 987                 $char = substr($body, $pos, 1);
 988                 /**
 989                  * Two things are valid here:
 990                  * '=' means this is attribute type 1 2 or 3.
 991                  * \w means this was attribute type 4.
 992                  * anything else we ignore and re-loop. End of tag and
 993                  * invalid stuff will be caught by our checks at the beginning
 994                  * of the loop.
 995                  */
 996                 if ($char == "="){
 997                     $pos++;
 998                     $pos = sq_skipspace($body, $pos);
 999                     /**
1000                      * Here are 3 possibilities:
1001                      * "'"  attribute type 1
1002                      * '"'  attribute type 2
1003                      * everything else is the content of tag type 3
1004                      */
1005                     $quot = substr($body, $pos, 1);
1006                     if ($quot == "'"){
1007                         $regary = sq_findnxreg($body, $pos+1, "\'");
1008                         if ($regary == false){
1009                             return Array(false, false, false, $lt, strlen($body));
1010                         }
1011                         list($pos, $attval, $match) = $regary;
1012                         $pos++;
1013                         $attary{$attname} = "'" . $attval . "'";
1014                     } else if ($quot == '"'){
1015                         $regary = sq_findnxreg($body, $pos+1, '\"');
1016                         if ($regary == false){
1017                             return Array(false, false, false, $lt, strlen($body));
1018                         }
1019                         list($pos, $attval, $match) = $regary;
1020                         $pos++;
1021                         $attary{$attname} = '"' . $attval . '"';
1022                     } else {
1023                         /**
1024                          * These are hateful. Look for \s, or >.
1025                          */
1026                         $regary = sq_findnxreg($body, $pos, "[\s>]");
1027                         if ($regary == false){
1028                             return Array(false, false, false, $lt, strlen($body));
1029                         }
1030                         list($pos, $attval, $match) = $regary;
1031                         /**
1032                          * If it's ">" it will be caught at the top.
1033                          */
1034                         $attval = preg_replace("/\"/s", "&quot;", $attval);
1035                         $attary{$attname} = '"' . $attval . '"';
1036                     }
1037                 } else if (preg_match("|[\w/>]|", $char)) {
1038                     /**
1039                      * That was attribute type 4.
1040                      */
1041                     $attary{$attname} = '"yes"';
1042                 } else {
1043                     /**
1044                      * An illegal character. Find next '>' and return.
1045                      */
1046                     $gt = sq_findnxstr($body, $pos, ">");
1047                     return Array(false, false, false, $lt, $gt);
1048                 }
1049                 break;
1050         }
1051     }
1052     /**
1053      * The fact that we got here indicates that the tag end was never
1054      * found. Return invalid tag indication so it gets stripped.
1055      */
1056     return Array(false, false, false, $lt, strlen($body));
1057 }
1058
1059 /**
1060  * This function checks attribute values for entity-encoded values
1061  * and returns them translated into 8-bit strings so we can run
1062  * checks on them.
1063  *
1064  * @param  $attvalue A string to run entity check against.
1065  * @return           Translated value.
1066  */
1067 function sq_deent($attvalue){
1068     $me = 'sq_deent';
1069     /**
1070      * See if we have to run the checks first. All entities must start
1071      * with "&".
1072      */
1073     if (strpos($attvalue, "&") === false){
1074         return $attvalue;
1075     }
1076     /**
1077      * Check named entities first.
1078      */
1079     $trans = get_html_translation_table(HTML_ENTITIES);
1080     /**
1081      * Leave &quot; in, as it can mess us up.
1082      */
1083     $trans = array_flip($trans);
1084     unset($trans{"&quot;"});
1085     while (list($ent, $val) = each($trans)){
1086         $attvalue = preg_replace("/$ent*(\W)/si", "$val\\1", $attvalue);
1087     }
1088     /**
1089      * Now translate numbered entities from 1 to 255 if needed.
1090      */
1091     if (strpos($attvalue, "#") !== false){
1092         $omit = Array(34, 39);
1093         for ($asc=1; $asc<256; $asc++){
1094             if (!in_array($asc, $omit)){
1095                 $chr = chr($asc);
1096                 $attvalue = preg_replace("/\&#0*$asc;*(\D)/si", "$chr\\1",
1097                                          $attvalue);
1098                 $attvalue = preg_replace("/\&#x0*".dechex($asc).";*(\W)/si",
1099                                          "$chr\\1", $attvalue);
1100             }
1101         }
1102     }
1103     return $attvalue;
1104 }
1105
1106 /**
1107  * This function runs various checks against the attributes.
1108  *
1109  * @param  $tagname         String with the name of the tag.
1110  * @param  $attary          Array with all tag attributes.
1111  * @param  $rm_attnames     See description for sq_sanitize
1112  * @param  $bad_attvals     See description for sq_sanitize
1113  * @param  $add_attr_to_tag See description for sq_sanitize
1114  * @param  $message         message object
1115  * @param  $id              message id
1116  * @return                  Array with modified attributes.
1117  */
1118 function sq_fixatts($tagname,
1119                     $attary,
1120                     $rm_attnames,
1121                     $bad_attvals,
1122                     $add_attr_to_tag,
1123                     $message,
1124                     $id,
1125                     $mailbox
1126                     ){
1127     $me = 'sq_fixatts';
1128     while (list($attname, $attvalue) = each($attary)){
1129         /**
1130          * See if this attribute should be removed.
1131          */
1132         foreach ($rm_attnames as $matchtag=>$matchattrs){
1133             if (preg_match($matchtag, $tagname)){
1134                 foreach ($matchattrs as $matchattr){
1135                     if (preg_match($matchattr, $attname)){
1136                         unset($attary{$attname});
1137                         continue;
1138                     }
1139                 }
1140             }
1141         }
1142         /**
1143          * Remove any entities.
1144          */
1145         $attvalue = sq_deent($attvalue);
1146
1147         /**
1148          * Now let's run checks on the attvalues.
1149          * I don't expect anyone to comprehend this. If you do,
1150          * get in touch with me so I can drive to where you live and
1151          * shake your hand personally. :)
1152          */
1153         foreach ($bad_attvals as $matchtag=>$matchattrs){
1154             if (preg_match($matchtag, $tagname)){
1155                 foreach ($matchattrs as $matchattr=>$valary){
1156                     if (preg_match($matchattr, $attname)){
1157                         /**
1158                          * There are two arrays in valary.
1159                          * First is matches.
1160                          * Second one is replacements
1161                          */
1162                         list($valmatch, $valrepl) = $valary;
1163                         $newvalue =
1164                             preg_replace($valmatch, $valrepl, $attvalue);
1165                         if ($newvalue != $attvalue){
1166                             $attary{$attname} = $newvalue;
1167                         }
1168                     }
1169                 }
1170             }
1171         }
1172         /**
1173          * Turn cid: urls into http-friendly ones.
1174          */
1175         if (preg_match("/^[\'\"]\s*cid:/si", $attvalue)){
1176             $attary{$attname} = sq_cid2http($message, $id, $attvalue, $mailbox);
1177         }
1178     }
1179     /**
1180      * See if we need to append any attributes to this tag.
1181      */
1182     foreach ($add_attr_to_tag as $matchtag=>$addattary){
1183         if (preg_match($matchtag, $tagname)){
1184             $attary = array_merge($attary, $addattary);
1185         }
1186     }
1187     return $attary;
1188 }
1189
1190 /**
1191  * This function edits the style definition to make them friendly and
1192  * usable in squirrelmail.
1193  *
1194  * @param  $message  the message object
1195  * @param  $id       the message id
1196  * @param  $content  a string with whatever is between <style> and </style>
1197  * @return           a string with edited content.
1198  */
1199 function sq_fixstyle($message, $id, $content){
1200     global $view_unsafe_images;
1201     $me = 'sq_fixstyle';
1202     /**
1203      * First look for general BODY style declaration, which would be
1204      * like so:
1205      * body {background: blah-blah}
1206      * and change it to .bodyclass so we can just assign it to a <div>
1207      */
1208     $content = preg_replace("|body(\s*\{.*?\})|si", ".bodyclass\\1", $content);
1209     $secremoveimg = '../images/' . _("sec_remove_eng.png");
1210     /**
1211      * Fix url('blah') declarations.
1212      */
1213     $content = preg_replace("|url\(([\'\"])\s*\S+script\s*:.*?([\'\"])\)|si",
1214                             "url(\\1$secremoveimg\\2)", $content);
1215     /**
1216      * Fix url('https*://.*) declarations but only if $view_unsafe_images
1217      * is false.
1218      */
1219     if (!$view_unsafe_images){
1220         $content = preg_replace("|url\(([\'\"])\s*https*:.*?([\'\"])\)|si",
1221                                 "url(\\1$secremoveimg\\2)", $content);
1222     }
1223
1224     /**
1225      * Fix urls that refer to cid:
1226      */
1227     while (preg_match("|url\(([\'\"]\s*cid:.*?[\'\"])\)|si", $content,
1228                       $matches)){
1229         $cidurl = $matches{1};
1230         $httpurl = sq_cid2http($message, $id, $cidurl);
1231         $content = preg_replace("|url\($cidurl\)|si",
1232                                 "url($httpurl)", $content);
1233     }
1234
1235     /**
1236      * Fix stupid css declarations which lead to vulnerabilities
1237      * in IE.
1238      */
1239     $match   = Array('/expression/si',
1240                      '/behaviou*r/si',
1241                      '/binding/si');
1242     $replace = Array('idiocy', 'idiocy', 'idiocy');
1243     $content = preg_replace($match, $replace, $content);
1244     return $content;
1245 }
1246
1247 /**
1248  * This function converts cid: url's into the ones that can be viewed in
1249  * the browser.
1250  *
1251  * @param  $message  the message object
1252  * @param  $id       the message id
1253  * @param  $cidurl   the cid: url.
1254  * @return           a string with a http-friendly url
1255  */
1256 function sq_cid2http($message, $id, $cidurl, $mailbox){
1257     /**
1258      * Get rid of quotes.
1259      */
1260     $quotchar = substr($cidurl, 0, 1);
1261     $cidurl = str_replace($quotchar, "", $cidurl);
1262     $cidurl = substr(trim($cidurl), 4);
1263     $linkurl = find_ent_id($cidurl, $message);
1264     /* in case of non-save cid links $httpurl should be replaced by a sort of
1265        unsave link image */
1266     $httpurl = '';
1267     if ($linkurl) {
1268         $httpurl = $quotchar . '../src/download.php?absolute_dl=true&amp;' .
1269                    "passed_id=$id&amp;mailbox=" . urlencode($mailbox) .
1270                    '&amp;ent_id=' . $linkurl . $quotchar;
1271     }
1272     return $httpurl;
1273 }
1274
1275 /**
1276  * This function changes the <body> tag into a <div> tag since we
1277  * can't really have a body-within-body.
1278  *
1279  * @param  $attary  an array of attributes and values of <body>
1280  * @return          a modified array of attributes to be set for <div>
1281  */
1282 function sq_body2div($attary){
1283     $me = 'sq_body2div';
1284     $divattary = Array('class' => "'bodyclass'");
1285     $bgcolor = '#ffffff';
1286     $text = '#000000';
1287     $styledef = '';
1288     if (is_array($attary) && sizeof($attary) > 0){
1289         foreach ($attary as $attname=>$attvalue){
1290             $quotchar = substr($attvalue, 0, 1);
1291             $attvalue = str_replace($quotchar, "", $attvalue);
1292             switch ($attname){
1293                 case 'background':
1294                     $styledef .= "background-image: url('$attvalue'); ";
1295                     break;
1296                 case 'bgcolor':
1297                     $styledef .= "background-color: $attvalue; ";
1298                     break;
1299                 case 'text':
1300                     $styledef .= "color: $attvalue; ";
1301                     break;
1302             }
1303         }
1304         if (strlen($styledef) > 0){
1305             $divattary{"style"} = "\"$styledef\"";
1306         }
1307     }
1308     return $divattary;
1309 }
1310
1311 /**
1312  * This is the main function and the one you should actually be calling.
1313  * There are several variables you should be aware of an which need
1314  * special description.
1315  *
1316  * Since the description is quite lengthy, see it here:
1317  * http://www.mricon.com/html/phpfilter.html
1318  *
1319  * @param $body                 the string with HTML you wish to filter
1320  * @param $tag_list             see description above
1321  * @param $rm_tags_with_content see description above
1322  * @param $self_closing_tags    see description above
1323  * @param $force_tag_closing    see description above
1324  * @param $rm_attnames          see description above
1325  * @param $bad_attvals          see description above
1326  * @param $add_attr_to_tag      see description above
1327  * @param $message              message object
1328  * @param $id                   message id
1329  * @return                      sanitized html safe to show on your pages.
1330  */
1331 function sq_sanitize($body,
1332                      $tag_list,
1333                      $rm_tags_with_content,
1334                      $self_closing_tags,
1335                      $force_tag_closing,
1336                      $rm_attnames,
1337                      $bad_attvals,
1338                      $add_attr_to_tag,
1339                      $message,
1340                      $id,
1341                      $mailbox
1342                      ){
1343     $me = 'sq_sanitize';
1344     /**
1345      * Normalize rm_tags and rm_tags_with_content.
1346      */
1347     @array_walk($rm_tags, 'sq_casenormalize');
1348     @array_walk($rm_tags_with_content, 'sq_casenormalize');
1349     @array_walk($self_closing_tags, 'sq_casenormalize');
1350     /**
1351      * See if tag_list is of tags to remove or tags to allow.
1352      * false  means remove these tags
1353      * true   means allow these tags
1354      */
1355     $rm_tags = array_shift($tag_list);
1356     $curpos = 0;
1357     $open_tags = Array();
1358     $trusted = "<!-- begin sanitized html -->\n";
1359     $skip_content = false;
1360     /**
1361      * Take care of netscape's stupid javascript entities like
1362      * &{alert('boo')};
1363      */
1364     $body = preg_replace("/&(\{.*?\};)/si", "&amp;\\1", $body);
1365
1366     while (($curtag=sq_getnxtag($body, $curpos)) != FALSE){
1367         list($tagname, $attary, $tagtype, $lt, $gt) = $curtag;
1368         $free_content = substr($body, $curpos, $lt-$curpos);
1369         /**
1370          * Take care of <style>
1371          */
1372         if ($tagname == "style" && $tagtype == 2){
1373             /**
1374              * This is a closing </style>. Edit the
1375              * content before we apply it.
1376              */
1377             $free_content = sq_fixstyle($message, $id, $free_content);
1378         }
1379         if ($skip_content == false){
1380             $trusted .= $free_content;
1381         }
1382         if ($tagname != FALSE){
1383             if ($tagtype == 2){
1384                 if ($skip_content == $tagname){
1385                     /**
1386                      * Got to the end of tag we needed to remove.
1387                      */
1388                     $tagname = false;
1389                     $skip_content = false;
1390                 } else {
1391                     if ($skip_content == false){
1392                         if ($tagname == "body"){
1393                             $tagname = "div";
1394                         } else {
1395                             if (isset($open_tags{$tagname}) &&
1396                                 $open_tags{$tagname} > 0){
1397                                 $open_tags{$tagname}--;
1398                             } else {
1399                                 $tagname = false;
1400                             }
1401                         }
1402                     }
1403                 }
1404             } else {
1405                 /**
1406                  * $rm_tags_with_content
1407                  */
1408                 if ($skip_content == false){
1409                     /**
1410                      * See if this is a self-closing type and change
1411                      * tagtype appropriately.
1412                      */
1413                     if ($tagtype == 1
1414                         && in_array($tagname, $self_closing_tags)){
1415                         $tagtype=3;
1416                     }
1417                     /**
1418                      * See if we should skip this tag and any content
1419                      * inside it.
1420                      */
1421                     if ($tagtype == 1 &&
1422                         in_array($tagname, $rm_tags_with_content)){
1423                         $skip_content = $tagname;
1424                     } else {
1425                         if (($rm_tags == false
1426                              && in_array($tagname, $tag_list)) ||
1427                             ($rm_tags == true &&
1428                              !in_array($tagname, $tag_list))){
1429                             $tagname = false;
1430                         } else {
1431                             if ($tagtype == 1){
1432                                 if (isset($open_tags{$tagname})){
1433                                     $open_tags{$tagname}++;
1434                                 } else {
1435                                     $open_tags{$tagname}=1;
1436                                 }
1437                             }
1438                             /**
1439                              * This is where we run other checks.
1440                              */
1441                             if (is_array($attary) && sizeof($attary) > 0){
1442                                 $attary = sq_fixatts($tagname,
1443                                                      $attary,
1444                                                      $rm_attnames,
1445                                                      $bad_attvals,
1446                                                      $add_attr_to_tag,
1447                                                      $message,
1448                                                      $id,
1449                                                      $mailbox
1450                                                      );
1451                             }
1452                             /**
1453                              * Convert body into div.
1454                              */
1455                             if ($tagname == "body"){
1456                                 $tagname = "div";
1457                                 $attary = sq_body2div($attary, $message, $id);
1458                             }
1459                         }
1460                     }
1461                 }
1462             }
1463             if ($tagname != false && $skip_content == false){
1464                 $trusted .= sq_tagprint($tagname, $attary, $tagtype);
1465             }
1466         }
1467         $curpos = $gt+1;
1468     }
1469     $trusted .= substr($body, $curpos, strlen($body)-$curpos);
1470     if ($force_tag_closing == true){
1471         foreach ($open_tags as $tagname=>$opentimes){
1472             while ($opentimes > 0){
1473                 $trusted .= '</' . $tagname . '>';
1474                 $opentimes--;
1475             }
1476         }
1477         $trusted .= "\n";
1478     }
1479     $trusted .= "<!-- end sanitized html -->\n";
1480     return $trusted;
1481 }
1482
1483 /**
1484  * This is a wrapper function to call html sanitizing routines.
1485  *
1486  * @param  $body  the body of the message
1487  * @param  $id    the id of the message
1488  * @return        a string with html safe to display in the browser.
1489  */
1490 function magicHTML($body, $id, $message, $mailbox = 'INBOX'){
1491     global $attachment_common_show_images, $view_unsafe_images,
1492            $has_unsafe_images;
1493     /**
1494      * Don't display attached images in HTML mode.
1495      */
1496     $attachment_common_show_images = false;
1497     $tag_list = Array(
1498                       false,
1499                       "object",
1500                       "meta",
1501                       "html",
1502                       "head",
1503                       "base",
1504                       "link",
1505                       "frame",
1506                       "iframe"
1507                       );
1508
1509     $rm_tags_with_content = Array(
1510                                   "script",
1511                                   "applet",
1512                                   "embed",
1513                                   "title"
1514                                   );
1515
1516     $self_closing_tags =  Array(
1517                                 "img",
1518                                 "br",
1519                                 "hr",
1520                                 "input"
1521                                 );
1522
1523     $force_tag_closing = false;
1524
1525     $rm_attnames = Array(
1526                          "/.*/" =>
1527                          Array(
1528                                "/target/si",
1529                                "/^on.*/si",
1530                                "/^dynsrc/si",
1531                                "/^data.*/si"
1532                                )
1533                          );
1534
1535     $secremoveimg = "../images/" . _("sec_remove_eng.png");
1536     $bad_attvals = Array(
1537         "/.*/" =>
1538             Array(
1539                 "/^src|background/i" =>
1540                     Array(
1541                           Array(
1542                                 "|^([\'\"])\s*\.\./.*([\'\"])|si",
1543                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1544                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1545                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1546                                 ),
1547                           Array(
1548                                 "\\1$secremoveimg\\2",
1549                                 "\\1$secremoveimg\\2",
1550                                 "\\1$secremoveimg\\2",
1551                                 "\\1$secremoveimg\\2"
1552                                 )
1553                         ),
1554                 "/^href|action/i" =>
1555                     Array(
1556                           Array(
1557                                 "|^([\'\"])\s*\.\./.*([\'\"])|si",
1558                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1559                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1560                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1561                                 ),
1562                           Array(
1563                                 "\\1#\\2",
1564                                 "\\1#\\2",
1565                                 "\\1#\\2",
1566                                 "\\1#\\2"
1567                                 )
1568                         ),
1569                 "/^style/si" =>
1570                     Array(
1571                           Array(
1572                                 "/expression/si",
1573                                 "/binding/si",
1574                                 "/behaviou*r/si",
1575                                 "|url\(([\'\"])\s*\.\./.*([\'\"])\)|si",
1576                                 "/url\(([\'\"])\s*\S+script\s*:.*([\'\"])\)/si",
1577                                 "/url\(([\'\"])\s*mocha\s*:.*([\'\"])\)/si",
1578                                 "/url\(([\'\"])\s*about\s*:.*([\'\"])\)/si"
1579                                ),
1580                           Array(
1581                                 "idiocy",
1582                                 "idiocy",
1583                                 "idiocy",
1584                                 "url(\\1#\\2)",
1585                                 "url(\\1#\\2)",
1586                                 "url(\\1#\\2)",
1587                                 "url(\\1#\\2)"
1588                                )
1589                           )
1590                 )
1591         );
1592     if (!$view_unsafe_images){
1593         /**
1594          * Remove any references to http/https if view_unsafe_images set
1595          * to false.
1596          */
1597          array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[0],
1598                     '/^([\'\"])\s*https*:.*([\'\"])/si');
1599          array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[1],
1600                     "\\1$secremoveimg\\2");
1601          array_push($bad_attvals{'/.*/'}{'/^style/si'}[0],
1602                     '/url\(([\'\"])\s*https*:.*([\'\"])\)/si');
1603          array_push($bad_attvals{'/.*/'}{'/^style/si'}[1],
1604                     "url(\\1$secremoveimg\\2)");
1605     }
1606
1607     $add_attr_to_tag = Array(
1608                              "/^a$/si" => Array('target'=>'"_new"')
1609                              );
1610     $trusted = sq_sanitize($body,
1611                            $tag_list,
1612                            $rm_tags_with_content,
1613                            $self_closing_tags,
1614                            $force_tag_closing,
1615                            $rm_attnames,
1616                            $bad_attvals,
1617                            $add_attr_to_tag,
1618                            $message,
1619                            $id,
1620                            $mailbox
1621                            );
1622     if (preg_match("|$secremoveimg|si", $trusted)){
1623         $has_unsafe_images = true;
1624     }
1625     return $trusted;
1626 }
1627
1628 ?>