functions/mime.php

   1 <?php
   2
   3 /**
   4  * mime.php
   5  *
   6  * Copyright (c) 1999-2003 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     $i = 0;
  33     $msg = Message::parseStructure($read,$i);
  34     if (!is_object($msg)) {
  35         include_once(SM_PATH . 'functions/display_messages.php');
  36         global $color, $mailbox;
  37         displayPageHeader( $color, urldecode($mailbox) );
  38         echo "<BODY TEXT=\"$color[8]\" BGCOLOR=\"$color[4]\" LINK=\"$color[7]\" VLINK=\"$color[7]\" ALINK=\"$color[7]\">\n\n" .
  39          '<CENTER>';
  40         $errormessage  = _("SquirrelMail could not decode the bodystructure of the message");
  41         $errormessage .= '<BR>'._("the provided bodystructure by your imap-server").':<BR><BR>';
  42         $errormessage .= '<table><tr><td>' . htmlspecialchars($read) . '</td></tr></table>';
  43         plain_error_message( $errormessage, $color );
  44         echo '</body></html>';
  45         exit;
  46     }
  47     if (count($flags)) {
  48         foreach ($flags as $flag) {
  49             $char = strtoupper($flag{1});
  50             switch ($char) {
  51                 case 'S':
  52                     if (strtolower($flag) == '\\seen') {
  53                         $msg->is_seen = true;
  54                     }
  55                     break;
  56                 case 'A':
  57                     if (strtolower($flag) == '\\answered') {
  58                         $msg->is_answered = true;
  59                     }
  60                     break;
  61                 case 'D':
  62                     if (strtolower($flag) == '\\deleted') {
  63                         $msg->is_deleted = true;
  64                     }
  65                     break;
  66                 case 'F':
  67                     if (strtolower($flag) == '\\flagged') {
  68                         $msg->is_flagged = true;
  69                     }
  70                     break;
  71                 case 'M':
  72                     if (strtolower($flag) == '$mdnsent') {
  73                         $msg->is_mdnsent = true;
  74                     }
  75                     break;
  76                 default:
  77                     break;
  78             }
  79         }
  80     }
  81     //    listEntities($msg);
  82     return $msg;
  83 }
  84
  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=1) {
  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         $cmd = "FETCH $id BODY[]";
 103     } else {
 104         $cmd = "FETCH $id BODY[$ent_id]";
 105     }
 106
 107     $data = sqimap_run_command ($imap_stream, $cmd, true, $response, $message, $uid_support);
 108     do {
 109         $topline = trim(array_shift($data));
 110     } while($topline && ($topline[0] == '*') && !preg_match('/\* [0-9]+ FETCH.*/i', $topline)) ;
 111
 112     $wholemessage = implode('', $data);
 113     if (ereg('\\{([^\\}]*)\\}', $topline, $regs)) {
 114         $ret = substr($wholemessage, 0, $regs[1]);
 115         /* There is some information in the content info header that could be important
 116          * in order to parse html messages. Let's get them here.
 117          */
 118         if ($ret{0} == '<') {
 119             $data = sqimap_run_command ($imap_stream, "FETCH $id BODY[$ent_id.MIME]", true, $response, $message, $uid_support);
 120         }
 121     } else if (ereg('"([^"]*)"', $topline, $regs)) {
 122         $ret = $regs[1];
 123     } else {
 124         global $where, $what, $mailbox, $passed_id, $startMessage;
 125         $par = 'mailbox=' . urlencode($mailbox) . '&amp;passed_id=' . $passed_id;
 126         if (isset($where) && isset($what)) {
 127             $par .= '&amp;where=' . urlencode($where) . '&amp;what=' . urlencode($what);
 128         } else {
 129             $par .= '&amp;startMessage=' . $startMessage . '&amp;show_more=0';
 130         }
 131         $par .= '&amp;response=' . urlencode($response) .
 132                 '&amp;message='  . urlencode($message)  .
 133                 '&amp;topline='  . urlencode($topline);
 134
 135         echo   '<tt><br>' .
 136                '<table width="80%"><tr>' .
 137                '<tr><td colspan=2>' .
 138                _("Body retrieval error. The reason for this is most probably that the message is malformed.") .
 139                '</td></tr>' .
 140                '<tr><td><b>' . _("Command:") . "</td><td>$cmd</td></tr>" .
 141                '<tr><td><b>' . _("Response:") . "</td><td>$response</td></tr>" .
 142                '<tr><td><b>' . _("Message:") . "</td><td>$message</td></tr>" .
 143                '<tr><td><b>' . _("FETCH line:") . "</td><td>$topline</td></tr>" .
 144                "</table><BR></tt></font><hr>";
 145
 146         $data = sqimap_run_command ($imap_stream, "FETCH $passed_id BODY[]", true, $response, $message, $uid_support);
 147         array_shift($data);
 148         $wholemessage = implode('', $data);
 149
 150         $ret = $wholemessage;
 151     }
 152     return $ret;
 153 }
 154
 155 function mime_print_body_lines ($imap_stream, $id, $ent_id=1, $encoding) {
 156     global $uid_support;
 157
 158     $sid = sqimap_session_id($uid_support);
 159     /* Don't kill the connection if the browser is over a dialup
 160      * and it would take over 30 seconds to download it.
 161      * Don´t call set_time_limit in safe mode.
 162      */
 163
 164     if (!ini_get('safe_mode')) {
 165         set_time_limit(0);
 166     }
 167     if ($uid_support) {
 168        $sid_s = substr($sid,0,strpos($sid, ' '));
 169     } else {
 170        $sid_s = $sid;
 171     }
 172
 173     $body = mime_fetch_body ($imap_stream, $id, $ent_id);
 174     echo decodeBody($body, $encoding);
 175     return;
 176 /*
 177     fputs ($imap_stream, "$sid FETCH $id BODY[$ent_id]\r\n");
 178     $cnt = 0;
 179     $continue = true;
 180     $read = fgets ($imap_stream,8192);
 181
 182
 183     // This could be bad -- if the section has sqimap_session_id() . ' OK'
 184     // or similar, it will kill the download.
 185     while (!ereg("^".$sid_s." (OK|BAD|NO)(.*)$", $read, $regs)) {
 186         if (trim($read) == ')==') {
 187             $read1 = $read;
 188             $read = fgets ($imap_stream,4096);
 189             if (ereg("^".$sid." (OK|BAD|NO)(.*)$", $read, $regs)) {
 190                 return;
 191             } else {
 192                 echo decodeBody($read1, $encoding) .
 193                      decodeBody($read, $encoding);
 194             }
 195         } else if ($cnt) {
 196             echo decodeBody($read, $encoding);
 197         }
 198         $read = fgets ($imap_stream,4096);
 199         $cnt++;
 200 //      break;
 201     }
 202 */
 203 }
 204
 205 /* -[ END MIME DECODING ]----------------------------------------------------------- */
 206
 207 /* This is here for debugging purposes.  It will print out a list
 208  * of all the entity IDs that are in the $message object.
 209  */
 210 function listEntities ($message) {
 211     if ($message) {
 212         echo "<tt>" . $message->entity_id . ' : ' . $message->type0 . '/' . $message->type1 . ' parent = '. $message->parent->entity_id. '<br>';
 213         for ($i = 0; isset($message->entities[$i]); $i++) {
 214             echo "$i : ";
 215             $msg = listEntities($message->entities[$i]);
 216
 217             if ($msg) {
 218                 echo "return: ";
 219                 return $msg;
 220             }
 221         }
 222     }
 223 }
 224
 225 function getPriorityStr($priority) {
 226     $priority_level = substr($priority,0,1);
 227
 228     switch($priority_level) {
 229         /* Check for a higher then normal priority. */
 230         case '1':
 231         case '2':
 232             $priority_string = _("High");
 233             break;
 234
 235         /* Check for a lower then normal priority. */
 236         case '4':
 237         case '5':
 238             $priority_string = _("Low");
 239             break;
 240
 241         /* Check for a normal priority. */
 242         case '3':
 243         default:
 244             $priority_level = '3';
 245             $priority_string = _("Normal");
 246             break;
 247
 248     }
 249     return $priority_string;
 250 }
 251
 252 /* returns a $message object for a particular entity id */
 253 function getEntity ($message, $ent_id) {
 254     return $message->getEntity($ent_id);
 255 }
 256
 257 /* translateText
 258  * Extracted from strings.php 23/03/2002
 259  */
 260
 261 function translateText(&$body, $wrap_at, $charset) {
 262     global $where, $what;   /* from searching */
 263     global $color;          /* color theme */
 264
 265     require_once(SM_PATH . 'functions/url_parser.php');
 266
 267     $body_ary = explode("\n", $body);
 268     for ($i=0; $i < count($body_ary); $i++) {
 269         $line = $body_ary[$i];
 270         if (strlen($line) - 2 >= $wrap_at) {
 271             sqWordWrap($line, $wrap_at);
 272         }
 273         $line = charset_decode($charset, $line);
 274         $line = str_replace("\t", '        ', $line);
 275
 276         parseUrl ($line);
 277
 278         $quotes = 0;
 279         $pos = 0;
 280         $j = strlen($line);
 281
 282         while ($pos < $j) {
 283             if ($line[$pos] == ' ') {
 284                 $pos++;
 285             } else if (strpos($line, '&gt;', $pos) === $pos) {
 286                 $pos += 4;
 287                 $quotes++;
 288             } else {
 289                 break;
 290             }
 291         }
 292
 293         if ($quotes > 1) {
 294             if (!isset($color[14])) {
 295                 $color[14] = '#FF0000';
 296             }
 297             $line = '<FONT COLOR="' . $color[14] . '">' . $line . '</FONT>';
 298         } elseif ($quotes) {
 299             if (!isset($color[13])) {
 300                 $color[13] = '#800000';
 301             }
 302             $line = '<FONT COLOR="' . $color[13] . '">' . $line . '</FONT>';
 303         }
 304
 305         $body_ary[$i] = $line;
 306     }
 307     $body = '<pre>' . implode("\n", $body_ary) . '</pre>';
 308 }
 309
 310
 311 /* This returns a parsed string called $body. That string can then
 312  * be displayed as the actual message in the HTML. It contains
 313  * everything needed, including HTML Tags, Attachments at the
 314  * bottom, etc.
 315  */
 316 function formatBody($imap_stream, $message, $color, $wrap_at, $ent_num, $id, $mailbox='INBOX') {
 317     /* This if statement checks for the entity to show as the
 318      * primary message. To add more of them, just put them in the
 319      * order that is their priority.
 320      */
 321     global $startMessage, $username, $key, $imapServerAddress, $imapPort,
 322            $show_html_default, $sort, $has_unsafe_images;
 323
 324     if( !sqgetGlobalVar('view_unsafe_images', $view_unsafe_images, SQ_GET) ) {
 325         $view_unsafe_images = false;
 326     }
 327
 328     $body = '';
 329     $urlmailbox = urlencode($mailbox);
 330     $body_message = getEntity($message, $ent_num);
 331     if (($body_message->header->type0 == 'text') ||
 332         ($body_message->header->type0 == 'rfc822')) {
 333         $body = mime_fetch_body ($imap_stream, $id, $ent_num);
 334         $body = decodeBody($body, $body_message->header->encoding);
 335         $hookResults = do_hook("message_body", $body);
 336         $body = $hookResults[1];
 337
 338         /* If there are other types that shouldn't be formatted, add
 339          * them here.
 340          */
 341
 342         if ($body_message->header->type1 == 'html') {
 343             if ($show_html_default <> 1) {
 344                 $entity_conv = array('&nbsp;' => ' ',
 345                                      '<p>'    => "\n",
 346                                      '<br>'   => "\n",
 347                                      '<P>'    => "\n",
 348                                      '<BR>'   => "\n",
 349                                      '&gt;'   => '>',
 350                                      '&lt;'   => '<');
 351                 $body = strtr($body, $entity_conv);
 352                 $body = strip_tags($body);
 353                 $body = trim($body);
 354                 translateText($body, $wrap_at,
 355                               $body_message->header->getParameter('charset'));
 356             } else {
 357                 $body = magicHTML($body, $id, $message, $mailbox);
 358             }
 359         } else {
 360             translateText($body, $wrap_at,
 361                           $body_message->header->getParameter('charset'));
 362         }
 363
 364         if ($view_unsafe_images) {
 365             $untext = '">' . _("Hide Unsafe Images");
 366         } else {
 367             if (isset($has_unsafe_images) && $has_unsafe_images) {
 368                 $untext = '&amp;view_unsafe_images=1">' . _("View Unsafe Images");
 369             } else {
 370                 $untext = '">';
 371             }
 372         }
 373         $body .= '<center><small><a href="read_body.php?passed_id=' . $id .
 374                  '&amp;passed_ent_id=' . $message->entity_id . '&amp;mailbox=' . $urlmailbox .
 375                  '&amp;sort=' . $sort . '&amp;startMessage=' . $startMessage . '&amp;show_more=0' .
 376                  $untext . '</a></small></center><br>' . "\n";
 377
 378     }
 379     return $body;
 380 }
 381
 382
 383 function formatAttachments($message, $exclude_id, $mailbox, $id) {
 384     global $where, $what, $startMessage, $color;
 385     static $ShownHTML = 0;
 386
 387     $att_ar = $message->getAttachments($exclude_id);
 388
 389     if (!count($att_ar)) return '';
 390
 391     $attachments = '';
 392
 393     $urlMailbox = urlencode($mailbox);
 394
 395     foreach ($att_ar as $att) {
 396         $ent = urldecode($att->entity_id);
 397         $header = $att->header;
 398         $type0 = strtolower($header->type0);
 399         $type1 = strtolower($header->type1);
 400         $name = '';
 401         $links['download link']['text'] = _("download");
 402         $links['download link']['href'] =
 403                 "../src/download.php?absolute_dl=true&amp;passed_id=$id&amp;mailbox=$urlMailbox&amp;ent_id=$ent";
 404         $ImageURL = '';
 405         if ($type0 =='message' && $type1 == 'rfc822') {
 406             $default_page = '../src/read_body.php';
 407             $rfc822_header = $att->rfc822_header;
 408             $filename = decodeHeader($rfc822_header->subject);
 409             if (trim( $filename ) == '') {
 410                 $filename = 'untitled-[' . $ent . ']' ;
 411             }
 412             $from_o = $rfc822_header->from;
 413             if (is_object($from_o)) {
 414                 $from_name = $from_o->getAddress(false);
 415             } else {
 416                 $from_name = _("Unknown sender");
 417             }
 418             $from_name = decodeHeader(htmlspecialchars($from_name));
 419             $description = $from_name;
 420         } else {
 421             $default_page = '../src/download.php';
 422             if (is_object($header->disposition)) {
 423                 $filename = decodeHeader($header->disposition->getProperty('filename'));
 424                 if (trim($filename) == '') {
 425                     $name = decodeHeader($header->disposition->getProperty('name'));
 426                     if (trim($name) == '') {
 427                         $name = decodeHeader($header->getParameter('name'));
 428                         if(trim($name) == '') {
 429                             if (trim( $header->id ) == '') {
 430                                 $filename = 'untitled-[' . $ent . ']' ;
 431                             } else {
 432                                 $filename = 'cid: ' . $header->id;
 433                             }
 434                         } else {
 435                             $filename = $name;
 436                         }
 437                     } else {
 438                         $filename = $name;
 439                     }
 440                 }
 441             } else {
 442                 if (trim( $header->id ) == '') {
 443                     $filename = 'untitled-[' . $ent . ']' ;
 444                 } else {
 445                     $filename = 'cid: ' . $header->id;
 446                 }
 447             }
 448
 449             if ($header->description) {
 450                 $description = htmlspecialchars($header->description);
 451             } else {
 452                 $description = '';
 453             }
 454         }
 455
 456         $display_filename = $filename;
 457         if (isset($passed_ent_id)) {
 458             $passed_ent_id_link = '&amp;passed_ent_id='.$passed_ent_id;
 459         } else {
 460             $passed_ent_id_link = '';
 461         }
 462         $defaultlink = $default_page . "?startMessage=$startMessage"
 463                      . "&amp;passed_id=$id&amp;mailbox=$urlMailbox"
 464                      . '&amp;ent_id='.$ent.$passed_ent_id_link.'&amp;absolute_dl=true';
 465         if ($where && $what) {
 466            $defaultlink .= '&amp;where='. urlencode($where).'&amp;what='.urlencode($what);
 467         }
 468         /* This executes the attachment hook with a specific MIME-type.
 469          * If that doesn't have results, it tries if there's a rule
 470          * for a more generic type.
 471          */
 472         $hookresults = do_hook("attachment $type0/$type1", $links,
 473                                $startMessage, $id, $urlMailbox, $ent, $defaultlink,
 474                                $display_filename, $where, $what);
 475         if(count($hookresults[1]) <= 1) {
 476             $hookresults = do_hook("attachment $type0/*", $links,
 477                                    $startMessage, $id, $urlMailbox, $ent, $defaultlink,
 478                                    $display_filename, $where, $what);
 479         }
 480
 481         $links = $hookresults[1];
 482         $defaultlink = $hookresults[6];
 483
 484         $attachments .= '<TR><TD>' .
 485                         "<A HREF=\"$defaultlink\">$display_filename</A>&nbsp;</TD>" .
 486                         '<TD><SMALL><b>' . show_readable_size($header->size) .
 487                         '</b>&nbsp;&nbsp;</small></TD>' .
 488                         "<TD><SMALL>[ $type0/$type1 ]&nbsp;</SMALL></TD>" .
 489                         '<TD><SMALL>';
 490         $attachments .= '<b>' . $description . '</b>';
 491         $attachments .= '</SMALL></TD><TD><SMALL>&nbsp;';
 492
 493         $skipspaces = 1;
 494         foreach ($links as $val) {
 495             if ($skipspaces) {
 496                 $skipspaces = 0;
 497             } else {
 498                 $attachments .= '&nbsp;&nbsp;|&nbsp;&nbsp;';
 499             }
 500             $attachments .= '<a href="' . $val['href'] . '">' .  $val['text'] . '</a>';
 501         }
 502         unset($links);
 503         $attachments .= "</TD></TR>\n";
 504     }
 505     return $attachments;
 506 }
 507
 508 /* This function decodes the body depending on the encoding type. */
 509 function decodeBody($body, $encoding) {
 510     global $languages, $squirrelmail_language;
 511     global $show_html_default;
 512
 513     $body = str_replace("\r\n", "\n", $body);
 514     $encoding = strtolower($encoding);
 515
 516     if ($encoding == 'quoted-printable' ||
 517         $encoding == 'quoted_printable') {
 518         $body = quoted_printable_decode($body);
 519
 520         while (ereg("=\n", $body)) {
 521             $body = ereg_replace ("=\n", '', $body);
 522         }
 523
 524     } else if ($encoding == 'base64') {
 525         $body = base64_decode($body);
 526     }
 527
 528     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 529         function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
 530         $body = $languages[$squirrelmail_language]['XTRA_CODE']('decode', $body);
 531     }
 532
 533     // All other encodings are returned raw.
 534     return $body;
 535 }
 536
 537 /*
 538  * This functions decode strings that is encoded according to
 539  * RFC1522 (MIME Part Two: Message Header Extensions for Non-ASCII Text).
 540  * Patched by Christian Schmidt <christian@ostenfeld.dk>  23/03/2002
 541  */
 542 function decodeHeader ($string, $utfencode=true) {
 543     global $languages, $squirrelmail_language;
 544     if (is_array($string)) {
 545         $string = implode("\n", $string);
 546     }
 547
 548     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 549         function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
 550         $string = $languages[$squirrelmail_language]['XTRA_CODE']('decodeheader', $string);
 551     }
 552
 553     $i = 0;
 554     while (preg_match('/^(.{' . $i . '})(.*)=\?([^?]*)\?(Q|B)\?([^?]*)\?=/Ui',
 555                       $string, $res)) {
 556         $prefix = $res[1];
 557         /* Ignore white-space between consecutive encoded-words. */
 558         if (strspn($res[2], " \t") != strlen($res[2])) {
 559             $prefix .= $res[2];
 560         }
 561
 562         if (ucfirst($res[4]) == 'B') {
 563             $replace = base64_decode($res[5]);
 564         } else {
 565             $replace = str_replace('_', ' ', $res[5]);
 566             $replace = preg_replace('/=([0-9a-f]{2})/ie', 'chr(hexdec("\1"))',
 567                                     $replace);
 568             /* Only encode into entities by default. Some places
 569              * don't need the encoding, like the compose form.
 570              */
 571             if ($utfencode) {
 572                 $replace = charset_decode($res[3], $replace);
 573             }
 574         }
 575         $string = $prefix . $replace . substr($string, strlen($res[0]));
 576         $i = strlen($prefix) + strlen($replace);
 577     }
 578     return $string;
 579 }
 580
 581 /*
 582  * Encode a string according to RFC 1522 for use in headers if it
 583  * contains 8-bit characters or anything that looks like it should
 584  * be encoded.
 585  */
 586 function encodeHeader ($string) {
 587     global $default_charset, $languages, $squirrelmail_language;
 588
 589     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 590         function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
 591         return  $languages[$squirrelmail_language]['XTRA_CODE']('encodeheader', $string);
 592     }
 593
 594     // Encode only if the string contains 8-bit characters or =?
 595     $j = strlen($string);
 596     $l = strstr($string, '=?');         // Must be encoded ?
 597     $ret = '';
 598     for($i = 0; $i < $j; ++$i) {
 599         switch($string{$i}) {
 600             case '=':
 601                 $ret .= '=3D';
 602                 break;
 603             case '?':
 604                 $ret .= '=3F';
 605                 break;
 606             case '_':
 607                 $ret .= '=5F';
 608                 break;
 609             case ' ':
 610                 $ret .= '_';
 611                 break;
 612             default:
 613                 $k = ord($string{$i});
 614                 if ($k > 126) {
 615                     $ret .= sprintf("=%02X", $k);
 616                     $l = TRUE;
 617                 } else {
 618                     $ret .= $string{$i};
 619                 }
 620                 break;
 621         }
 622     }
 623
 624     if ($l) {
 625         $string = "=?$default_charset?Q?$ret?=";
 626     }
 627
 628     return $string;
 629 }
 630
 631 /* This function trys to locate the entity_id of a specific mime element */
 632 function find_ent_id($id, $message) {
 633     for ($i = 0, $ret = ''; $ret == '' && $i < count($message->entities); $i++) {
 634         if ($message->entities[$i]->header->type0 == 'multipart')  {
 635             $ret = find_ent_id($id, $message->entities[$i]);
 636         } else {
 637             if (strcasecmp($message->entities[$i]->header->id, $id) == 0) {
 638 //                if (sq_check_save_extension($message->entities[$i])) {
 639                     return $message->entities[$i]->entity_id;
 640 //                }
 641             }
 642         }
 643     }
 644     return $ret;
 645 }
 646
 647 function sq_check_save_extension($message) {
 648     $filename = $message->getFilename();
 649     $ext = substr($filename, strrpos($filename,'.')+1);
 650     $save_extensions = array('jpg','jpeg','gif','png','bmp');
 651     return in_array($ext, $save_extensions);
 652 }
 653
 654
 655 /**
 656  ** HTMLFILTER ROUTINES
 657  */
 658
 659 /**
 660  * This function returns the final tag out of the tag name, an array
 661  * of attributes, and the type of the tag. This function is called by
 662  * sq_sanitize internally.
 663  *
 664  * @param  $tagname  the name of the tag.
 665  * @param  $attary   the array of attributes and their values
 666  * @param  $tagtype  The type of the tag (see in comments).
 667  * @return           a string with the final tag representation.
 668  */
 669 function sq_tagprint($tagname, $attary, $tagtype){
 670     $me = 'sq_tagprint';
 671
 672     if ($tagtype == 2){
 673         $fulltag = '</' . $tagname . '>';
 674     } else {
 675         $fulltag = '<' . $tagname;
 676         if (is_array($attary) && sizeof($attary)){
 677             $atts = Array();
 678             while (list($attname, $attvalue) = each($attary)){
 679                 array_push($atts, "$attname=$attvalue");
 680             }
 681             $fulltag .= ' ' . join(" ", $atts);
 682         }
 683         if ($tagtype == 3){
 684             $fulltag .= ' /';
 685         }
 686         $fulltag .= '>';
 687     }
 688     return $fulltag;
 689 }
 690
 691 /**
 692  * A small helper function to use with array_walk. Modifies a by-ref
 693  * value and makes it lowercase.
 694  *
 695  * @param  $val a value passed by-ref.
 696  * @return      void since it modifies a by-ref value.
 697  */
 698 function sq_casenormalize(&$val){
 699     $val = strtolower($val);
 700 }
 701
 702 /**
 703  * This function skips any whitespace from the current position within
 704  * a string and to the next non-whitespace value.
 705  *
 706  * @param  $body   the string
 707  * @param  $offset the offset within the string where we should start
 708  *                 looking for the next non-whitespace character.
 709  * @return         the location within the $body where the next
 710  *                 non-whitespace char is located.
 711  */
 712 function sq_skipspace($body, $offset){
 713     $me = 'sq_skipspace';
 714     preg_match('/^(\s*)/s', substr($body, $offset), $matches);
 715     if (sizeof($matches{1})){
 716         $count = strlen($matches{1});
 717         $offset += $count;
 718     }
 719     return $offset;
 720 }
 721
 722 /**
 723  * This function looks for the next character within a string.  It's
 724  * really just a glorified "strpos", except it catches if failures
 725  * nicely.
 726  *
 727  * @param  $body   The string to look for needle in.
 728  * @param  $offset Start looking from this position.
 729  * @param  $needle The character/string to look for.
 730  * @return         location of the next occurance of the needle, or
 731  *                 strlen($body) if needle wasn't found.
 732  */
 733 function sq_findnxstr($body, $offset, $needle){
 734     $me  = 'sq_findnxstr';
 735     $pos = strpos($body, $needle, $offset);
 736     if ($pos === FALSE){
 737         $pos = strlen($body);
 738     }
 739     return $pos;
 740 }
 741
 742 /**
 743  * This function takes a PCRE-style regexp and tries to match it
 744  * within the string.
 745  *
 746  * @param  $body   The string to look for needle in.
 747  * @param  $offset Start looking from here.
 748  * @param  $reg    A PCRE-style regex to match.
 749  * @return         Returns a false if no matches found, or an array
 750  *                 with the following members:
 751  *                 - integer with the location of the match within $body
 752  *                 - string with whatever content between offset and the match
 753  *                 - string with whatever it is we matched
 754  */
 755 function sq_findnxreg($body, $offset, $reg){
 756     $me = 'sq_findnxreg';
 757     $matches = Array();
 758     $retarr = Array();
 759     preg_match("%^(.*?)($reg)%s", substr($body, $offset), $matches);
 760     if (!$matches{0}){
 761         $retarr = false;
 762     } else {
 763         $retarr{0} = $offset + strlen($matches{1});
 764         $retarr{1} = $matches{1};
 765         $retarr{2} = $matches{2};
 766     }
 767     return $retarr;
 768 }
 769
 770 /**
 771  * This function looks for the next tag.
 772  *
 773  * @param  $body   String where to look for the next tag.
 774  * @param  $offset Start looking from here.
 775  * @return         false if no more tags exist in the body, or
 776  *                 an array with the following members:
 777  *                 - string with the name of the tag
 778  *                 - array with attributes and their values
 779  *                 - integer with tag type (1, 2, or 3)
 780  *                 - integer where the tag starts (starting "<")
 781  *                 - integer where the tag ends (ending ">")
 782  *                 first three members will be false, if the tag is invalid.
 783  */
 784 function sq_getnxtag($body, $offset){
 785     $me = 'sq_getnxtag';
 786     if ($offset > strlen($body)){
 787         return false;
 788     }
 789     $lt = sq_findnxstr($body, $offset, "<");
 790     if ($lt == strlen($body)){
 791         return false;
 792     }
 793     /**
 794      * We are here:
 795      * blah blah <tag attribute="value">
 796      * \---------^
 797      */
 798     $pos = sq_skipspace($body, $lt+1);
 799     if ($pos >= strlen($body)){
 800         return Array(false, false, false, $lt, strlen($body));
 801     }
 802     /**
 803      * There are 3 kinds of tags:
 804      * 1. Opening tag, e.g.:
 805      *    <a href="blah">
 806      * 2. Closing tag, e.g.:
 807      *    </a>
 808      * 3. XHTML-style content-less tag, e.g.:
 809      *    <img src="blah"/>
 810      */
 811     $tagtype = false;
 812     switch (substr($body, $pos, 1)){
 813         case '/':
 814             $tagtype = 2;
 815             $pos++;
 816             break;
 817         case '!':
 818             /**
 819              * A comment or an SGML declaration.
 820              */
 821             if (substr($body, $pos+1, 2) == "--"){
 822                 $gt = strpos($body, "-->", $pos);
 823                 if ($gt === false){
 824                     $gt = strlen($body);
 825                 } else {
 826                     $gt += 2;
 827                 }
 828                 return Array(false, false, false, $lt, $gt);
 829             } else {
 830                 $gt = sq_findnxstr($body, $pos, ">");
 831                 return Array(false, false, false, $lt, $gt);
 832             }
 833             break;
 834         default:
 835             /**
 836              * Assume tagtype 1 for now. If it's type 3, we'll switch values
 837              * later.
 838              */
 839             $tagtype = 1;
 840             break;
 841     }
 842
 843     $tag_start = $pos;
 844     $tagname = '';
 845     /**
 846      * Look for next [\W-_], which will indicate the end of the tag name.
 847      */
 848     $regary = sq_findnxreg($body, $pos, "[^\w\-_]");
 849     if ($regary == false){
 850         return Array(false, false, false, $lt, strlen($body));
 851     }
 852     list($pos, $tagname, $match) = $regary;
 853     $tagname = strtolower($tagname);
 854
 855     /**
 856      * $match can be either of these:
 857      * '>'  indicating the end of the tag entirely.
 858      * '\s' indicating the end of the tag name.
 859      * '/'  indicating that this is type-3 xhtml tag.
 860      *
 861      * Whatever else we find there indicates an invalid tag.
 862      */
 863     switch ($match){
 864         case '/':
 865             /**
 866              * This is an xhtml-style tag with a closing / at the
 867              * end, like so: <img src="blah"/>. Check if it's followed
 868              * by the closing bracket. If not, then this tag is invalid
 869              */
 870             if (substr($body, $pos, 2) == "/>"){
 871                 $pos++;
 872                 $tagtype = 3;
 873             } else {
 874                 $gt = sq_findnxstr($body, $pos, ">");
 875                 $retary = Array(false, false, false, $lt, $gt);
 876                 return $retary;
 877             }
 878         case '>':
 879             return Array($tagname, false, $tagtype, $lt, $pos);
 880             break;
 881         default:
 882             /**
 883              * Check if it's whitespace
 884              */
 885             if (!preg_match('/\s/', $match)){
 886                 /**
 887                  * This is an invalid tag! Look for the next closing ">".
 888                  */
 889                 $gt = sq_findnxstr($body, $offset, ">");
 890                 return Array(false, false, false, $lt, $gt);
 891             }
 892             break;
 893     }
 894
 895     /**
 896      * At this point we're here:
 897      * <tagname  attribute='blah'>
 898      * \-------^
 899      *
 900      * At this point we loop in order to find all attributes.
 901      */
 902     $attname = '';
 903     $atttype = false;
 904     $attary = Array();
 905
 906     while ($pos <= strlen($body)){
 907         $pos = sq_skipspace($body, $pos);
 908         if ($pos == strlen($body)){
 909             /**
 910              * Non-closed tag.
 911              */
 912             return Array(false, false, false, $lt, $pos);
 913         }
 914         /**
 915          * See if we arrived at a ">" or "/>", which means that we reached
 916          * the end of the tag.
 917          */
 918         $matches = Array();
 919         if (preg_match("%^(\s*)(>|/>)%s", substr($body, $pos), $matches)) {
 920             /**
 921              * Yep. So we did.
 922              */
 923             $pos += strlen($matches{1});
 924             if ($matches{2} == "/>"){
 925                 $tagtype = 3;
 926                 $pos++;
 927             }
 928             return Array($tagname, $attary, $tagtype, $lt, $pos);
 929         }
 930
 931         /**
 932          * There are several types of attributes, with optional
 933          * [:space:] between members.
 934          * Type 1:
 935          *   attrname[:space:]=[:space:]'CDATA'
 936          * Type 2:
 937          *   attrname[:space:]=[:space:]"CDATA"
 938          * Type 3:
 939          *   attr[:space:]=[:space:]CDATA
 940          * Type 4:
 941          *   attrname
 942          *
 943          * We leave types 1 and 2 the same, type 3 we check for
 944          * '"' and convert to "&quot" if needed, then wrap in
 945          * double quotes. Type 4 we convert into:
 946          * attrname="yes".
 947          */
 948         $regary = sq_findnxreg($body, $pos, "[^\w\-_]");
 949         if ($regary == false){
 950             /**
 951              * Looks like body ended before the end of tag.
 952              */
 953             return Array(false, false, false, $lt, strlen($body));
 954         }
 955         list($pos, $attname, $match) = $regary;
 956         $attname = strtolower($attname);
 957         /**
 958          * We arrived at the end of attribute name. Several things possible
 959          * here:
 960          * '>'  means the end of the tag and this is attribute type 4
 961          * '/'  if followed by '>' means the same thing as above
 962          * '\s' means a lot of things -- look what it's followed by.
 963          *      anything else means the attribute is invalid.
 964          */
 965         switch($match){
 966             case '/':
 967                 /**
 968                  * This is an xhtml-style tag with a closing / at the
 969                  * end, like so: <img src="blah"/>. Check if it's followed
 970                  * by the closing bracket. If not, then this tag is invalid
 971                  */
 972                 if (substr($body, $pos, 2) == "/>"){
 973                     $pos++;
 974                     $tagtype = 3;
 975                 } else {
 976                     $gt = sq_findnxstr($body, $pos, ">");
 977                     $retary = Array(false, false, false, $lt, $gt);
 978                     return $retary;
 979                 }
 980             case '>':
 981                 $attary{$attname} = '"yes"';
 982                 return Array($tagname, $attary, $tagtype, $lt, $pos);
 983                 break;
 984             default:
 985                 /**
 986                  * Skip whitespace and see what we arrive at.
 987                  */
 988                 $pos = sq_skipspace($body, $pos);
 989                 $char = substr($body, $pos, 1);
 990                 /**
 991                  * Two things are valid here:
 992                  * '=' means this is attribute type 1 2 or 3.
 993                  * \w means this was attribute type 4.
 994                  * anything else we ignore and re-loop. End of tag and
 995                  * invalid stuff will be caught by our checks at the beginning
 996                  * of the loop.
 997                  */
 998                 if ($char == "="){
 999                     $pos++;
1000                     $pos = sq_skipspace($body, $pos);
1001                     /**
1002                      * Here are 3 possibilities:
1003                      * "'"  attribute type 1
1004                      * '"'  attribute type 2
1005                      * everything else is the content of tag type 3
1006                      */
1007                     $quot = substr($body, $pos, 1);
1008                     if ($quot == "'"){
1009                         $regary = sq_findnxreg($body, $pos+1, "\'");
1010                         if ($regary == false){
1011                             return Array(false, false, false, $lt, strlen($body));
1012                         }
1013                         list($pos, $attval, $match) = $regary;
1014                         $pos++;
1015                         $attary{$attname} = "'" . $attval . "'";
1016                     } else if ($quot == '"'){
1017                         $regary = sq_findnxreg($body, $pos+1, '\"');
1018                         if ($regary == false){
1019                             return Array(false, false, false, $lt, strlen($body));
1020                         }
1021                         list($pos, $attval, $match) = $regary;
1022                         $pos++;
1023                         $attary{$attname} = '"' . $attval . '"';
1024                     } else {
1025                         /**
1026                          * These are hateful. Look for \s, or >.
1027                          */
1028                         $regary = sq_findnxreg($body, $pos, "[\s>]");
1029                         if ($regary == false){
1030                             return Array(false, false, false, $lt, strlen($body));
1031                         }
1032                         list($pos, $attval, $match) = $regary;
1033                         /**
1034                          * If it's ">" it will be caught at the top.
1035                          */
1036                         $attval = preg_replace("/\"/s", "&quot;", $attval);
1037                         $attary{$attname} = '"' . $attval . '"';
1038                     }
1039                 } else if (preg_match("|[\w/>]|", $char)) {
1040                     /**
1041                      * That was attribute type 4.
1042                      */
1043                     $attary{$attname} = '"yes"';
1044                 } else {
1045                     /**
1046                      * An illegal character. Find next '>' and return.
1047                      */
1048                     $gt = sq_findnxstr($body, $pos, ">");
1049                     return Array(false, false, false, $lt, $gt);
1050                 }
1051                 break;
1052         }
1053     }
1054     /**
1055      * The fact that we got here indicates that the tag end was never
1056      * found. Return invalid tag indication so it gets stripped.
1057      */
1058     return Array(false, false, false, $lt, strlen($body));
1059 }
1060
1061 /**
1062  * This function checks attribute values for entity-encoded values
1063  * and returns them translated into 8-bit strings so we can run
1064  * checks on them.
1065  *
1066  * @param  $attvalue A string to run entity check against.
1067  * @return           Translated value.
1068  */
1069 function sq_deent($attvalue){
1070     $me = 'sq_deent';
1071     /**
1072      * See if we have to run the checks first. All entities must start
1073      * with "&".
1074      */
1075     if (strpos($attvalue, "&") === false){
1076         return $attvalue;
1077     }
1078     /**
1079      * Check named entities first.
1080      */
1081     $trans = get_html_translation_table(HTML_ENTITIES);
1082     /**
1083      * Leave &quot; in, as it can mess us up.
1084      */
1085     $trans = array_flip($trans);
1086     unset($trans{"&quot;"});
1087     while (list($ent, $val) = each($trans)){
1088         $attvalue = preg_replace("/$ent*(\W)/si", "$val\\1", $attvalue);
1089     }
1090     /**
1091      * Now translate numbered entities from 1 to 255 if needed.
1092      */
1093     if (strpos($attvalue, "#") !== false){
1094         $omit = Array(34, 39);
1095         for ($asc=1; $asc<256; $asc++){
1096             if (!in_array($asc, $omit)){
1097                 $chr = chr($asc);
1098                 $attvalue = preg_replace("/\&#0*$asc;*(\D)/si", "$chr\\1",
1099                                          $attvalue);
1100                 $attvalue = preg_replace("/\&#x0*".dechex($asc).";*(\W)/si",
1101                                          "$chr\\1", $attvalue);
1102             }
1103         }
1104     }
1105     return $attvalue;
1106 }
1107
1108 /**
1109  * This function runs various checks against the attributes.
1110  *
1111  * @param  $tagname         String with the name of the tag.
1112  * @param  $attary          Array with all tag attributes.
1113  * @param  $rm_attnames     See description for sq_sanitize
1114  * @param  $bad_attvals     See description for sq_sanitize
1115  * @param  $add_attr_to_tag See description for sq_sanitize
1116  * @param  $message         message object
1117  * @param  $id              message id
1118  * @return                  Array with modified attributes.
1119  */
1120 function sq_fixatts($tagname,
1121                     $attary,
1122                     $rm_attnames,
1123                     $bad_attvals,
1124                     $add_attr_to_tag,
1125                     $message,
1126                     $id,
1127                     $mailbox
1128                     ){
1129     $me = 'sq_fixatts';
1130     while (list($attname, $attvalue) = each($attary)){
1131         /**
1132          * See if this attribute should be removed.
1133          */
1134         foreach ($rm_attnames as $matchtag=>$matchattrs){
1135             if (preg_match($matchtag, $tagname)){
1136                 foreach ($matchattrs as $matchattr){
1137                     if (preg_match($matchattr, $attname)){
1138                         unset($attary{$attname});
1139                         continue;
1140                     }
1141                 }
1142             }
1143         }
1144         /**
1145          * Remove any entities.
1146          */
1147         $attvalue = sq_deent($attvalue);
1148
1149         /**
1150          * Now let's run checks on the attvalues.
1151          * I don't expect anyone to comprehend this. If you do,
1152          * get in touch with me so I can drive to where you live and
1153          * shake your hand personally. :)
1154          */
1155         foreach ($bad_attvals as $matchtag=>$matchattrs){
1156             if (preg_match($matchtag, $tagname)){
1157                 foreach ($matchattrs as $matchattr=>$valary){
1158                     if (preg_match($matchattr, $attname)){
1159                         /**
1160                          * There are two arrays in valary.
1161                          * First is matches.
1162                          * Second one is replacements
1163                          */
1164                         list($valmatch, $valrepl) = $valary;
1165                         $newvalue =
1166                             preg_replace($valmatch, $valrepl, $attvalue);
1167                         if ($newvalue != $attvalue){
1168                             $attary{$attname} = $newvalue;
1169                         }
1170                     }
1171                 }
1172             }
1173         }
1174         /**
1175          * Turn cid: urls into http-friendly ones.
1176          */
1177         if (preg_match("/^[\'\"]\s*cid:/si", $attvalue)){
1178             $attary{$attname} = sq_cid2http($message, $id, $attvalue, $mailbox);
1179         }
1180     }
1181     /**
1182      * See if we need to append any attributes to this tag.
1183      */
1184     foreach ($add_attr_to_tag as $matchtag=>$addattary){
1185         if (preg_match($matchtag, $tagname)){
1186             $attary = array_merge($attary, $addattary);
1187         }
1188     }
1189     return $attary;
1190 }
1191
1192 /**
1193  * This function edits the style definition to make them friendly and
1194  * usable in squirrelmail.
1195  *
1196  * @param  $message  the message object
1197  * @param  $id       the message id
1198  * @param  $content  a string with whatever is between <style> and </style>
1199  * @return           a string with edited content.
1200  */
1201 function sq_fixstyle($message, $id, $content){
1202     global $view_unsafe_images;
1203     $me = 'sq_fixstyle';
1204     /**
1205      * First look for general BODY style declaration, which would be
1206      * like so:
1207      * body {background: blah-blah}
1208      * and change it to .bodyclass so we can just assign it to a <div>
1209      */
1210     $content = preg_replace("|body(\s*\{.*?\})|si", ".bodyclass\\1", $content);
1211     $secremoveimg = '../images/' . _("sec_remove_eng.png");
1212     /**
1213      * Fix url('blah') declarations.
1214      */
1215     $content = preg_replace("|url\(([\'\"])\s*\S+script\s*:.*?([\'\"])\)|si",
1216                             "url(\\1$secremoveimg\\2)", $content);
1217     /**
1218      * Fix url('https*://.*) declarations but only if $view_unsafe_images
1219      * is false.
1220      */
1221     if (!$view_unsafe_images){
1222         $content = preg_replace("|url\(([\'\"])\s*https*:.*?([\'\"])\)|si",
1223                                 "url(\\1$secremoveimg\\2)", $content);
1224     }
1225
1226     /**
1227      * Fix urls that refer to cid:
1228      */
1229     while (preg_match("|url\(([\'\"]\s*cid:.*?[\'\"])\)|si", $content,
1230                       $matches)){
1231         $cidurl = $matches{1};
1232         $httpurl = sq_cid2http($message, $id, $cidurl);
1233         $content = preg_replace("|url\($cidurl\)|si",
1234                                 "url($httpurl)", $content);
1235     }
1236
1237     /**
1238      * Fix stupid css declarations which lead to vulnerabilities
1239      * in IE.
1240      */
1241     $match   = Array('/expression/si',
1242                      '/behaviou*r/si',
1243                      '/binding/si');
1244     $replace = Array('idiocy', 'idiocy', 'idiocy');
1245     $content = preg_replace($match, $replace, $content);
1246     return $content;
1247 }
1248
1249 /**
1250  * This function converts cid: url's into the ones that can be viewed in
1251  * the browser.
1252  *
1253  * @param  $message  the message object
1254  * @param  $id       the message id
1255  * @param  $cidurl   the cid: url.
1256  * @return           a string with a http-friendly url
1257  */
1258 function sq_cid2http($message, $id, $cidurl, $mailbox){
1259     /**
1260      * Get rid of quotes.
1261      */
1262     $quotchar = substr($cidurl, 0, 1);
1263     $cidurl = str_replace($quotchar, "", $cidurl);
1264     $cidurl = substr(trim($cidurl), 4);
1265     $linkurl = find_ent_id($cidurl, $message);
1266     /* in case of non-save cid links $httpurl should be replaced by a sort of
1267        unsave link image */
1268     $httpurl = '';
1269     if ($linkurl) {
1270         $httpurl = $quotchar . '../src/download.php?absolute_dl=true&amp;' .
1271                    "passed_id=$id&amp;mailbox=" . urlencode($mailbox) .
1272                    '&amp;ent_id=' . $linkurl . $quotchar;
1273     }
1274     return $httpurl;
1275 }
1276
1277 /**
1278  * This function changes the <body> tag into a <div> tag since we
1279  * can't really have a body-within-body.
1280  *
1281  * @param  $attary  an array of attributes and values of <body>
1282  * @return          a modified array of attributes to be set for <div>
1283  */
1284 function sq_body2div($attary){
1285     $me = 'sq_body2div';
1286     $divattary = Array('class' => "'bodyclass'");
1287     $bgcolor = '#ffffff';
1288     $text = '#000000';
1289     $styledef = '';
1290     if (is_array($attary) && sizeof($attary) > 0){
1291         foreach ($attary as $attname=>$attvalue){
1292             $quotchar = substr($attvalue, 0, 1);
1293             $attvalue = str_replace($quotchar, "", $attvalue);
1294             switch ($attname){
1295                 case 'background':
1296                     $styledef .= "background-image: url('$attvalue'); ";
1297                     break;
1298                 case 'bgcolor':
1299                     $styledef .= "background-color: $attvalue; ";
1300                     break;
1301                 case 'text':
1302                     $styledef .= "color: $attvalue; ";
1303                     break;
1304             }
1305         }
1306         if (strlen($styledef) > 0){
1307             $divattary{"style"} = "\"$styledef\"";
1308         }
1309     }
1310     return $divattary;
1311 }
1312
1313 /**
1314  * This is the main function and the one you should actually be calling.
1315  * There are several variables you should be aware of an which need
1316  * special description.
1317  *
1318  * Since the description is quite lengthy, see it here:
1319  * http://www.mricon.com/html/phpfilter.html
1320  *
1321  * @param $body                 the string with HTML you wish to filter
1322  * @param $tag_list             see description above
1323  * @param $rm_tags_with_content see description above
1324  * @param $self_closing_tags    see description above
1325  * @param $force_tag_closing    see description above
1326  * @param $rm_attnames          see description above
1327  * @param $bad_attvals          see description above
1328  * @param $add_attr_to_tag      see description above
1329  * @param $message              message object
1330  * @param $id                   message id
1331  * @return                      sanitized html safe to show on your pages.
1332  */
1333 function sq_sanitize($body,
1334                      $tag_list,
1335                      $rm_tags_with_content,
1336                      $self_closing_tags,
1337                      $force_tag_closing,
1338                      $rm_attnames,
1339                      $bad_attvals,
1340                      $add_attr_to_tag,
1341                      $message,
1342                      $id,
1343                      $mailbox
1344                      ){
1345     $me = 'sq_sanitize';
1346     /**
1347      * Normalize rm_tags and rm_tags_with_content.
1348      */
1349     @array_walk($rm_tags, 'sq_casenormalize');
1350     @array_walk($rm_tags_with_content, 'sq_casenormalize');
1351     @array_walk($self_closing_tags, 'sq_casenormalize');
1352     /**
1353      * See if tag_list is of tags to remove or tags to allow.
1354      * false  means remove these tags
1355      * true   means allow these tags
1356      */
1357     $rm_tags = array_shift($tag_list);
1358     $curpos = 0;
1359     $open_tags = Array();
1360     $trusted = "<!-- begin sanitized html -->\n";
1361     $skip_content = false;
1362     /**
1363      * Take care of netscape's stupid javascript entities like
1364      * &{alert('boo')};
1365      */
1366     $body = preg_replace("/&(\{.*?\};)/si", "&amp;\\1", $body);
1367
1368     while (($curtag=sq_getnxtag($body, $curpos)) != FALSE){
1369         list($tagname, $attary, $tagtype, $lt, $gt) = $curtag;
1370         $free_content = substr($body, $curpos, $lt-$curpos);
1371         /**
1372          * Take care of <style>
1373          */
1374         if ($tagname == "style" && $tagtype == 2){
1375             /**
1376              * This is a closing </style>. Edit the
1377              * content before we apply it.
1378              */
1379             $free_content = sq_fixstyle($message, $id, $free_content);
1380         }
1381         if ($skip_content == false){
1382             $trusted .= $free_content;
1383         }
1384         if ($tagname != FALSE){
1385             if ($tagtype == 2){
1386                 if ($skip_content == $tagname){
1387                     /**
1388                      * Got to the end of tag we needed to remove.
1389                      */
1390                     $tagname = false;
1391                     $skip_content = false;
1392                 } else {
1393                     if ($skip_content == false){
1394                         if ($tagname == "body"){
1395                             $tagname = "div";
1396                         } else {
1397                             if (isset($open_tags{$tagname}) &&
1398                                 $open_tags{$tagname} > 0){
1399                                 $open_tags{$tagname}--;
1400                             } else {
1401                                 $tagname = false;
1402                             }
1403                         }
1404                     }
1405                 }
1406             } else {
1407                 /**
1408                  * $rm_tags_with_content
1409                  */
1410                 if ($skip_content == false){
1411                     /**
1412                      * See if this is a self-closing type and change
1413                      * tagtype appropriately.
1414                      */
1415                     if ($tagtype == 1
1416                         && in_array($tagname, $self_closing_tags)){
1417                         $tagtype=3;
1418                     }
1419                     /**
1420                      * See if we should skip this tag and any content
1421                      * inside it.
1422                      */
1423                     if ($tagtype == 1 &&
1424                         in_array($tagname, $rm_tags_with_content)){
1425                         $skip_content = $tagname;
1426                     } else {
1427                         if (($rm_tags == false
1428                              && in_array($tagname, $tag_list)) ||
1429                             ($rm_tags == true &&
1430                              !in_array($tagname, $tag_list))){
1431                             $tagname = false;
1432                         } else {
1433                             if ($tagtype == 1){
1434                                 if (isset($open_tags{$tagname})){
1435                                     $open_tags{$tagname}++;
1436                                 } else {
1437                                     $open_tags{$tagname}=1;
1438                                 }
1439                             }
1440                             /**
1441                              * This is where we run other checks.
1442                              */
1443                             if (is_array($attary) && sizeof($attary) > 0){
1444                                 $attary = sq_fixatts($tagname,
1445                                                      $attary,
1446                                                      $rm_attnames,
1447                                                      $bad_attvals,
1448                                                      $add_attr_to_tag,
1449                                                      $message,
1450                                                      $id,
1451                                                      $mailbox
1452                                                      );
1453                             }
1454                             /**
1455                              * Convert body into div.
1456                              */
1457                             if ($tagname == "body"){
1458                                 $tagname = "div";
1459                                 $attary = sq_body2div($attary, $message, $id);
1460                             }
1461                         }
1462                     }
1463                 }
1464             }
1465             if ($tagname != false && $skip_content == false){
1466                 $trusted .= sq_tagprint($tagname, $attary, $tagtype);
1467             }
1468         }
1469         $curpos = $gt+1;
1470     }
1471     $trusted .= substr($body, $curpos, strlen($body)-$curpos);
1472     if ($force_tag_closing == true){
1473         foreach ($open_tags as $tagname=>$opentimes){
1474             while ($opentimes > 0){
1475                 $trusted .= '</' . $tagname . '>';
1476                 $opentimes--;
1477             }
1478         }
1479         $trusted .= "\n";
1480     }
1481     $trusted .= "<!-- end sanitized html -->\n";
1482     return $trusted;
1483 }
1484
1485 /**
1486  * This is a wrapper function to call html sanitizing routines.
1487  *
1488  * @param  $body  the body of the message
1489  * @param  $id    the id of the message
1490  * @return        a string with html safe to display in the browser.
1491  */
1492 function magicHTML($body, $id, $message, $mailbox = 'INBOX') {
1493     global $attachment_common_show_images, $view_unsafe_images,
1494            $has_unsafe_images;
1495     /**
1496      * Don't display attached images in HTML mode.
1497      */
1498     $attachment_common_show_images = false;
1499     $tag_list = Array(
1500                       false,
1501                       "object",
1502                       "meta",
1503                       "html",
1504                       "head",
1505                       "base",
1506                       "link",
1507                       "frame",
1508                       "iframe"
1509                       );
1510
1511     $rm_tags_with_content = Array(
1512                                   "script",
1513                                   "applet",
1514                                   "embed",
1515                                   "title"
1516                                   );
1517
1518     $self_closing_tags =  Array(
1519                                 "img",
1520                                 "br",
1521                                 "hr",
1522                                 "input"
1523                                 );
1524
1525     $force_tag_closing = false;
1526
1527     $rm_attnames = Array(
1528                          "/.*/" =>
1529                          Array(
1530                                "/target/si",
1531                                "/^on.*/si",
1532                                "/^dynsrc/si",
1533                                "/^data.*/si"
1534                                )
1535                          );
1536
1537     $secremoveimg = "../images/" . _("sec_remove_eng.png");
1538     $bad_attvals = Array(
1539         "/.*/" =>
1540             Array(
1541                 "/^src|background/i" =>
1542                     Array(
1543                           Array(
1544                                 "|^([\'\"])\s*\.\./.*([\'\"])|si",
1545                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1546                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1547                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1548                                 ),
1549                           Array(
1550                                 "\\1$secremoveimg\\2",
1551                                 "\\1$secremoveimg\\2",
1552                                 "\\1$secremoveimg\\2",
1553                                 "\\1$secremoveimg\\2"
1554                                 )
1555                         ),
1556                 "/^href|action/i" =>
1557                     Array(
1558                           Array(
1559                                 "|^([\'\"])\s*\.\./.*([\'\"])|si",
1560                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1561                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1562                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1563                                 ),
1564                           Array(
1565                                 "\\1#\\2",
1566                                 "\\1#\\2",
1567                                 "\\1#\\2",
1568                                 "\\1#\\2"
1569                                 )
1570                         ),
1571                 "/^style/si" =>
1572                     Array(
1573                           Array(
1574                                 "/expression/si",
1575                                 "/binding/si",
1576                                 "/behaviou*r/si",
1577                                 "|url\(([\'\"])\s*\.\./.*([\'\"])\)|si",
1578                                 "/url\(([\'\"])\s*\S+script\s*:.*([\'\"])\)/si",
1579                                 "/url\(([\'\"])\s*mocha\s*:.*([\'\"])\)/si",
1580                                 "/url\(([\'\"])\s*about\s*:.*([\'\"])\)/si"
1581                                ),
1582                           Array(
1583                                 "idiocy",
1584                                 "idiocy",
1585                                 "idiocy",
1586                                 "url(\\1#\\2)",
1587                                 "url(\\1#\\2)",
1588                                 "url(\\1#\\2)",
1589                                 "url(\\1#\\2)"
1590                                )
1591                           )
1592                 )
1593         );
1594     if( !sqgetGlobalVar('view_unsafe_images', $view_unsafe_images, SQ_GET) ) {
1595         $view_unsafe_images = false;
1596     }
1597     if (!$view_unsafe_images){
1598         /**
1599          * Remove any references to http/https if view_unsafe_images set
1600          * to false.
1601          */
1602          array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[0],
1603                     '/^([\'\"])\s*https*:.*([\'\"])/si');
1604          array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[1],
1605                     "\\1$secremoveimg\\2");
1606          array_push($bad_attvals{'/.*/'}{'/^style/si'}[0],
1607                     '/url\(([\'\"])\s*https*:.*([\'\"])\)/si');
1608          array_push($bad_attvals{'/.*/'}{'/^style/si'}[1],
1609                     "url(\\1$secremoveimg\\2)");
1610     }
1611
1612     $add_attr_to_tag = Array(
1613                              "/^a$/si" => Array('target'=>'"_new"')
1614                              );
1615     $trusted = sq_sanitize($body,
1616                            $tag_list,
1617                            $rm_tags_with_content,
1618                            $self_closing_tags,
1619                            $force_tag_closing,
1620                            $rm_attnames,
1621                            $bad_attvals,
1622                            $add_attr_to_tag,
1623                            $message,
1624                            $id,
1625                            $mailbox
1626                            );
1627     if (preg_match("|$secremoveimg|si", $trusted)){
1628         $has_unsafe_images = true;
1629     }
1630     return $trusted;
1631 }
1632
1633 ?>