functions/mime.php

   1 <?php
   2
   3 /**
   4 * mime.php
   5 *
   6 * Copyright (c) 1999-2005 The SquirrelMail Project Team
   7 * Licensed under the GNU GPL. For full terms see the file COPYING.
   8 *
   9 * This contains the functions necessary to detect and decode MIME
  10 * messages.
  11 *
  12 * @version $Id$
  13 * @package squirrelmail
  14 */
  15
  16 /** The typical includes... */
  17 require_once(SM_PATH . 'functions/imap.php');
  18 require_once(SM_PATH . 'functions/attachment_common.php');
  19
  20 /* -------------------------------------------------------------------------- */
  21 /* MIME DECODING                                                              */
  22 /* -------------------------------------------------------------------------- */
  23
  24 /**
  25 * Get the MIME structure
  26 *
  27 * This function gets the structure of a message and stores it in the "message" class.
  28 * It will return this object for use with all relevant header information and
  29 * fully parsed into the standard "message" object format.
  30 */
  31 function mime_structure ($bodystructure, $flags=array()) {
  32
  33     /* Isolate the body structure and remove beginning and end parenthesis. */
  34     $read = trim(substr ($bodystructure, strpos(strtolower($bodystructure), 'bodystructure') + 13));
  35     $read = trim(substr ($read, 0, -1));
  36     $i = 0;
  37     $msg = Message::parseStructure($read,$i);
  38     if (!is_object($msg)) {
  39         include_once(SM_PATH . 'functions/display_messages.php');
  40         global $color, $mailbox;
  41         /* removed urldecode because $_GET is auto urldecoded ??? */
  42         displayPageHeader( $color, $mailbox );
  43         $errormessage  = _("SquirrelMail could not decode the bodystructure of the message");
  44         $errormessage .= '<br />'._("the provided bodystructure by your imap-server").':<br /><br />';
  45         $errormessage .= '<pre>' . htmlspecialchars($read) . '</pre>';
  46         plain_error_message( $errormessage, $color );
  47         echo '</body></html>';
  48         exit;
  49     }
  50     if (count($flags)) {
  51         foreach ($flags as $flag) {
  52             $char = strtoupper($flag{1});
  53             switch ($char) {
  54                 case 'S':
  55                     if (strtolower($flag) == '\\seen') {
  56                         $msg->is_seen = true;
  57                     }
  58                     break;
  59                 case 'A':
  60                     if (strtolower($flag) == '\\answered') {
  61                         $msg->is_answered = true;
  62                     }
  63                     break;
  64                 case 'D':
  65                     if (strtolower($flag) == '\\deleted') {
  66                         $msg->is_deleted = true;
  67                     }
  68                     break;
  69                 case 'F':
  70                     if (strtolower($flag) == '\\flagged') {
  71                         $msg->is_flagged = true;
  72                     }
  73                     break;
  74                 case 'M':
  75                     if (strtolower($flag) == '$mdnsent') {
  76                         $msg->is_mdnsent = true;
  77                     }
  78                     break;
  79                 default:
  80                     break;
  81             }
  82         }
  83     }
  84     //    listEntities($msg);
  85     return $msg;
  86 }
  87
  88
  89
  90 /* This starts the parsing of a particular structure.  It is called recursively,
  91 * so it can be passed different structures.  It returns an object of type
  92 * $message.
  93 * First, it checks to see if it is a multipart message.  If it is, then it
  94 * handles that as it sees is necessary.  If it is just a regular entity,
  95 * then it parses it and adds the necessary header information (by calling out
  96 * to mime_get_elements()
  97 */
  98
  99 function mime_fetch_body($imap_stream, $id, $ent_id=1, $fetch_size=0) {
 100     /* Do a bit of error correction.  If we couldn't find the entity id, just guess
 101     * that it is the first one.  That is usually the case anyway.
 102     */
 103
 104     if (!$ent_id) {
 105         $cmd = "FETCH $id BODY[]";
 106     } else {
 107         $cmd = "FETCH $id BODY[$ent_id]";
 108     }
 109
 110     if ($fetch_size!=0) $cmd .= "<0.$fetch_size>";
 111
 112     $data = sqimap_run_command ($imap_stream, $cmd, true, $response, $message, TRUE);
 113     do {
 114         $topline = trim(array_shift($data));
 115     } while($topline && ($topline[0] == '*') && !preg_match('/\* [0-9]+ FETCH.*/i', $topline)) ;
 116
 117     $wholemessage = implode('', $data);
 118     if (ereg('\\{([^\\}]*)\\}', $topline, $regs)) {
 119         $ret = substr($wholemessage, 0, $regs[1]);
 120         /* There is some information in the content info header that could be important
 121         * in order to parse html messages. Let's get them here.
 122         */
 123 //        if ($ret{0} == '<') {
 124 //            $data = sqimap_run_command ($imap_stream, "FETCH $id BODY[$ent_id.MIME]", true, $response, $message, TRUE);
 125 //        }
 126     } else if (ereg('"([^"]*)"', $topline, $regs)) {
 127         $ret = $regs[1];
 128     } else {
 129         global $where, $what, $mailbox, $passed_id, $startMessage;
 130         $par = 'mailbox=' . urlencode($mailbox) . '&amp;passed_id=' . $passed_id;
 131         if (isset($where) && isset($what)) {
 132             $par .= '&amp;where=' . urlencode($where) . '&amp;what=' . urlencode($what);
 133         } else {
 134             $par .= '&amp;startMessage=' . $startMessage . '&amp;show_more=0';
 135         }
 136         $par .= '&amp;response=' . urlencode($response) .
 137                 '&amp;message='  . urlencode($message)  .
 138                 '&amp;topline='  . urlencode($topline);
 139
 140         echo   '<tt><br />' .
 141             '<table width="80%"><tr>' .
 142             '<tr><td colspan="2">' .
 143             _("Body retrieval error. The reason for this is most probably that the message is malformed.") .
 144             '</td></tr>' .
 145             '<tr><td><b>' . _("Command:") . "</td><td>$cmd</td></tr>" .
 146             '<tr><td><b>' . _("Response:") . "</td><td>$response</td></tr>" .
 147             '<tr><td><b>' . _("Message:") . "</td><td>$message</td></tr>" .
 148             '<tr><td><b>' . _("FETCH line:") . "</td><td>$topline</td></tr>" .
 149             "</table><br /></tt></font><hr />";
 150
 151         $data = sqimap_run_command ($imap_stream, "FETCH $passed_id BODY[]", true, $response, $message, TRUE);
 152         array_shift($data);
 153         $wholemessage = implode('', $data);
 154
 155         $ret = $wholemessage;
 156     }
 157     return $ret;
 158 }
 159
 160 function mime_print_body_lines ($imap_stream, $id, $ent_id=1, $encoding) {
 161
 162     /* Don't kill the connection if the browser is over a dialup
 163     * and it would take over 30 seconds to download it.
 164     * Don't call set_time_limit in safe mode.
 165     */
 166
 167     if (!ini_get('safe_mode')) {
 168         set_time_limit(0);
 169     }
 170     /* in case of base64 encoded attachments, do not buffer them.
 171     Instead, echo the decoded attachment directly to screen */
 172     if (strtolower($encoding) == 'base64') {
 173         if (!$ent_id) {
 174         $query = "FETCH $id BODY[]";
 175         } else {
 176         $query = "FETCH $id BODY[$ent_id]";
 177         }
 178         sqimap_run_command($imap_stream,$query,true,$response,$message,TRUE,'sqimap_base64_decode','php://stdout',true);
 179     } else {
 180     $body = mime_fetch_body ($imap_stream, $id, $ent_id);
 181     echo decodeBody($body, $encoding);
 182     }
 183
 184     /*
 185     TODO, use the same method for quoted printable.
 186     However, I assume that quoted printable attachments aren't that large
 187     so the performancegain / memory usage drop will be minimal.
 188     If we decide to add that then we need to adapt sqimap_fread because
 189     we need to split te result on \n and fread doesn't stop at \n. That
 190     means we also should provide $results from sqimap_fread (by ref) to
 191     te function and set $no_return to false. The $filter function for
 192     quoted printable should handle unsetting of $results.
 193     */
 194     /*
 195     TODO 2: find out how we write to the output stream php://stdout. fwrite
 196     doesn't work because 'php://stdout isn't a stream.
 197     */
 198
 199     return;
 200 /*
 201     fputs ($imap_stream, "$sid FETCH $id BODY[$ent_id]\r\n");
 202     $cnt = 0;
 203     $continue = true;
 204     $read = fgets ($imap_stream,8192);
 205
 206
 207     // This could be bad -- if the section has sqimap_session_id() . ' OK'
 208     // or similar, it will kill the download.
 209     while (!ereg("^".$sid_s." (OK|BAD|NO)(.*)$", $read, $regs)) {
 210         if (trim($read) == ')==') {
 211             $read1 = $read;
 212             $read = fgets ($imap_stream,4096);
 213             if (ereg("^".$sid." (OK|BAD|NO)(.*)$", $read, $regs)) {
 214                 return;
 215             } else {
 216                 echo decodeBody($read1, $encoding) .
 217                     decodeBody($read, $encoding);
 218             }
 219         } else if ($cnt) {
 220             echo decodeBody($read, $encoding);
 221         }
 222         $read = fgets ($imap_stream,4096);
 223         $cnt++;
 224 //      break;
 225     }
 226 */
 227 }
 228
 229 /* -[ END MIME DECODING ]----------------------------------------------------------- */
 230
 231 /* This is here for debugging purposes.  It will print out a list
 232 * of all the entity IDs that are in the $message object.
 233 */
 234 function listEntities ($message) {
 235     if ($message) {
 236         echo "<tt>" . $message->entity_id . ' : ' . $message->type0 . '/' . $message->type1 . ' parent = '. $message->parent->entity_id. '<br />';
 237         for ($i = 0; isset($message->entities[$i]); $i++) {
 238             echo "$i : ";
 239             $msg = listEntities($message->entities[$i]);
 240
 241             if ($msg) {
 242                 echo "return: ";
 243                 return $msg;
 244             }
 245         }
 246     }
 247 }
 248
 249 function getPriorityStr($priority) {
 250     $priority_level = substr($priority,0,1);
 251
 252     switch($priority_level) {
 253         /* Check for a higher then normal priority. */
 254         case '1':
 255         case '2':
 256             $priority_string = _("High");
 257             break;
 258
 259         /* Check for a lower then normal priority. */
 260         case '4':
 261         case '5':
 262             $priority_string = _("Low");
 263             break;
 264
 265         /* Check for a normal priority. */
 266         case '3':
 267         default:
 268             $priority_level = '3';
 269             $priority_string = _("Normal");
 270             break;
 271
 272     }
 273     return $priority_string;
 274 }
 275
 276 /* returns a $message object for a particular entity id */
 277 function getEntity ($message, $ent_id) {
 278     return $message->getEntity($ent_id);
 279 }
 280
 281 /* translateText
 282 * Extracted from strings.php 23/03/2002
 283 */
 284
 285 function translateText(&$body, $wrap_at, $charset) {
 286     global $where, $what;   /* from searching */
 287     global $color;          /* color theme */
 288
 289     require_once(SM_PATH . 'functions/url_parser.php');
 290
 291     $body_ary = explode("\n", $body);
 292     for ($i=0; $i < count($body_ary); $i++) {
 293         $line = $body_ary[$i];
 294         if (strlen($line) - 2 >= $wrap_at) {
 295             sqWordWrap($line, $wrap_at, $charset);
 296         }
 297         $line = charset_decode($charset, $line);
 298         $line = str_replace("\t", '        ', $line);
 299
 300         parseUrl ($line);
 301
 302         $quotes = 0;
 303         $pos = 0;
 304         $j = strlen($line);
 305
 306         while ($pos < $j) {
 307             if ($line[$pos] == ' ') {
 308                 $pos++;
 309             } else if (strpos($line, '&gt;', $pos) === $pos) {
 310                 $pos += 4;
 311                 $quotes++;
 312             } else {
 313                 break;
 314             }
 315         }
 316
 317         if ($quotes % 2) {
 318             if (!isset($color[13])) {
 319                 $color[13] = '#800000';
 320             }
 321             $line = '<font color="' . $color[13] . '">' . $line . '</font>';
 322         } elseif ($quotes) {
 323             if (!isset($color[14])) {
 324                 $color[14] = '#FF0000';
 325             }
 326             $line = '<font color="' . $color[14] . '">' . $line . '</font>';
 327         }
 328
 329         $body_ary[$i] = $line;
 330     }
 331     $body = '<pre>' . implode("\n", $body_ary) . '</pre>';
 332 }
 333
 334 /**
 335 * This returns a parsed string called $body. That string can then
 336 * be displayed as the actual message in the HTML. It contains
 337 * everything needed, including HTML Tags, Attachments at the
 338 * bottom, etc.
 339 * @param clean Do not output stuff that's irrelevant for the printable version.
 340 */
 341 function formatBody($imap_stream, $message, $color, $wrap_at, $ent_num, $id, $mailbox='INBOX', $clean=FALSE) {
 342     /* This if statement checks for the entity to show as the
 343     * primary message. To add more of them, just put them in the
 344     * order that is their priority.
 345     */
 346     global $startMessage, $languages, $squirrelmail_language,
 347         $show_html_default, $sort, $has_unsafe_images, $passed_ent_id;
 348
 349     if( !sqgetGlobalVar('view_unsafe_images', $view_unsafe_images, SQ_GET) ) {
 350         $view_unsafe_images = false;
 351     }
 352
 353     $body = '';
 354     $urlmailbox = urlencode($mailbox);
 355     $body_message = getEntity($message, $ent_num);
 356     if (($body_message->header->type0 == 'text') ||
 357         ($body_message->header->type0 == 'rfc822')) {
 358         $body = mime_fetch_body ($imap_stream, $id, $ent_num);
 359         $body = decodeBody($body, $body_message->header->encoding);
 360
 361         if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 362             function_exists($languages[$squirrelmail_language]['XTRA_CODE'] . '_decode')) {
 363             if (mb_detect_encoding($body) != 'ASCII') {
 364                 $body = call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_decode',$body);
 365             }
 366         }
 367         $hookResults = do_hook("message_body", $body);
 368         $body = $hookResults[1];
 369
 370         /* If there are other types that shouldn't be formatted, add
 371         * them here.
 372         */
 373
 374         if ($body_message->header->type1 == 'html') {
 375             if ($show_html_default <> 1) {
 376                 $entity_conv = array('&nbsp;' => ' ',
 377                                     '<p>'    => "\n",
 378                                     '<P>'    => "\n",
 379                                     '<br>'   => "\n",
 380                                     '<BR>'   => "\n",
 381                                     '<br />' => "\n",
 382                                     '<BR />' => "\n",
 383                                     '&gt;'   => '>',
 384                                     '&lt;'   => '<');
 385                 $body = strtr($body, $entity_conv);
 386                 $body = strip_tags($body);
 387                 $body = trim($body);
 388                 translateText($body, $wrap_at,
 389                             $body_message->header->getParameter('charset'));
 390             } else {
 391                 $body = magicHTML($body, $id, $message, $mailbox);
 392             }
 393         } else {
 394             translateText($body, $wrap_at,
 395                         $body_message->header->getParameter('charset'));
 396         }
 397
 398         // if this is the clean display (i.e. printer friendly), stop here.
 399         if ( $clean ) {
 400             return $body;
 401         }
 402
 403         $link = 'passed_id=' . $id . '&amp;ent_id='.$ent_num.
 404                 '&amp;mailbox=' . $urlmailbox .'&amp;sort=' . $sort .
 405                 '&amp;startMessage=' . $startMessage . '&amp;show_more=0';
 406         if (isset($passed_ent_id)) {
 407             $link .= '&amp;passed_ent_id='.$passed_ent_id;
 408         }
 409         $body .= '<center><small><a href="download.php?absolute_dl=true&amp;' .
 410                 $link . '">' . _("Download this as a file") .  '</a>';
 411         if ($view_unsafe_images) {
 412             $text = _("Hide Unsafe Images");
 413         } else {
 414             if (isset($has_unsafe_images) && $has_unsafe_images) {
 415                 $link .= '&amp;view_unsafe_images=1';
 416                 $text = _("View Unsafe Images");
 417             } else {
 418                 $text = '';
 419             }
 420         }
 421         if($text != '') {
 422             $body .= '&nbsp;|&nbsp;<a href="read_body.php?' . $link . '">' . $text . '</a>';
 423         }
 424         $body .= '</small></center><br />' . "\n";
 425     }
 426     return $body;
 427 }
 428
 429
 430 function formatAttachments($message, $exclude_id, $mailbox, $id) {
 431     global $where, $what, $startMessage, $color, $passed_ent_id;
 432
 433     $att_ar = $message->getAttachments($exclude_id);
 434
 435     if (!count($att_ar)) return '';
 436
 437     $attachments = '';
 438
 439     $urlMailbox = urlencode($mailbox);
 440
 441     foreach ($att_ar as $att) {
 442         $ent = $att->entity_id;
 443         $header = $att->header;
 444         $type0 = strtolower($header->type0);
 445         $type1 = strtolower($header->type1);
 446         $name = '';
 447         $links['download link']['text'] = _("Download");
 448         $links['download link']['href'] = SM_PATH .
 449                 "src/download.php?absolute_dl=true&amp;passed_id=$id&amp;mailbox=$urlMailbox&amp;ent_id=$ent";
 450         if ($type0 =='message' && $type1 == 'rfc822') {
 451             $default_page = SM_PATH . 'src/read_body.php';
 452             $rfc822_header = $att->rfc822_header;
 453             $filename = $rfc822_header->subject;
 454             if (trim( $filename ) == '') {
 455                 $filename = 'untitled-[' . $ent . ']' ;
 456             }
 457             $from_o = $rfc822_header->from;
 458             if (is_object($from_o)) {
 459                 $from_name = decodeHeader($from_o->getAddress(false));
 460             } else {
 461                 $from_name = _("Unknown sender");
 462             }
 463             $description = $from_name;
 464         } else {
 465             $default_page = SM_PATH . 'src/download.php';
 466             $filename = $att->getFilename();
 467             if ($header->description) {
 468                 $description = decodeHeader($header->description);
 469             } else {
 470                 $description = '';
 471             }
 472         }
 473
 474         $display_filename = $filename;
 475         if (isset($passed_ent_id)) {
 476             $passed_ent_id_link = '&amp;passed_ent_id='.$passed_ent_id;
 477         } else {
 478             $passed_ent_id_link = '';
 479         }
 480         $defaultlink = $default_page . "?startMessage=$startMessage"
 481                     . "&amp;passed_id=$id&amp;mailbox=$urlMailbox"
 482                     . '&amp;ent_id='.$ent.$passed_ent_id_link;
 483         if ($where && $what) {
 484         $defaultlink .= '&amp;where='. urlencode($where).'&amp;what='.urlencode($what);
 485         }
 486
 487         /* This executes the attachment hook with a specific MIME-type.
 488         * If that doesn't have results, it tries if there's a rule
 489         * for a more generic type.
 490         */
 491         $hookresults = do_hook("attachment $type0/$type1", $links,
 492                             $startMessage, $id, $urlMailbox, $ent, $defaultlink,
 493                             $display_filename, $where, $what);
 494         if(count($hookresults[1]) <= 1) {
 495             $hookresults = do_hook("attachment $type0/*", $links,
 496                                 $startMessage, $id, $urlMailbox, $ent, $defaultlink,
 497                                 $display_filename, $where, $what);
 498         }
 499
 500         $links = $hookresults[1];
 501         $defaultlink = $hookresults[6];
 502
 503         $attachments .= '<tr><td>' .
 504                         '<a href="'.$defaultlink.'">'.decodeHeader($display_filename).'</a>&nbsp;</td>' .
 505                         '<td><small><b>' . show_readable_size($header->size) .
 506                         '</b>&nbsp;&nbsp;</small></td>' .
 507                         '<td><small>[ '.htmlspecialchars($type0).'/'.htmlspecialchars($type1).' ]&nbsp;</small></td>' .
 508                         '<td><small>';
 509         $attachments .= '<b>' . $description . '</b>';
 510         $attachments .= '</small></td><td><small>&nbsp;';
 511
 512         $skipspaces = 1;
 513         foreach ($links as $val) {
 514             if ($skipspaces) {
 515                 $skipspaces = 0;
 516             } else {
 517                 $attachments .= '&nbsp;&nbsp;|&nbsp;&nbsp;';
 518             }
 519             $attachments .= '<a href="' . $val['href'] . '">' .  $val['text'] . '</a>';
 520         }
 521         unset($links);
 522         $attachments .= "</td></tr>\n";
 523     }
 524     $attachmentadd = do_hook_function('attachments_bottom',$attachments);
 525     if ($attachmentadd != '')
 526         $attachments = $attachmentadd;
 527     return $attachments;
 528 }
 529
 530 function sqimap_base64_decode(&$string) {
 531
 532     // Base64 encoded data goes in pairs of 4 bytes. To achieve on the
 533     // fly decoding (to reduce memory usage) you have to check if the
 534     // data has incomplete pairs
 535
 536     // Remove the noise in order to check if the 4 bytes pairs are complete
 537     $string = str_replace(array("\r\n","\n", "\r", " "),array('','','',''),$string);
 538
 539     $sStringRem = '';
 540     $iMod = strlen($string) % 4;
 541     if ($iMod) {
 542         $sStringRem = substr($string,-$iMod);
 543         // Check if $sStringRem contains padding characters
 544         if (substr($sStringRem,-1) != '=') {
 545             $string = substr($string,0,-$iMod);
 546         } else {
 547             $sStringRem = '';
 548         }
 549     }
 550     $string = base64_decode($string);
 551     return $sStringRem;
 552 }
 553
 554
 555 /* This function decodes the body depending on the encoding type. */
 556 function decodeBody($body, $encoding) {
 557     global $show_html_default;
 558
 559     $body = str_replace("\r\n", "\n", $body);
 560     $encoding = strtolower($encoding);
 561
 562     $encoding_handler = do_hook_function('decode_body', $encoding);
 563
 564
 565     // plugins get first shot at decoding the body
 566     //
 567     if (!empty($encoding_handler) && function_exists($encoding_handler)) {
 568         $body = $encoding_handler('decode', $body);
 569
 570     } else if ($encoding == 'quoted-printable' ||
 571         $encoding == 'quoted_printable') {
 572         $body = quoted_printable_decode($body);
 573
 574         while (ereg("=\n", $body)) {
 575             $body = ereg_replace ("=\n", '', $body);
 576         }
 577
 578     } else if ($encoding == 'base64') {
 579         $body = base64_decode($body);
 580     }
 581
 582     // All other encodings are returned raw.
 583     return $body;
 584 }
 585
 586 /**
 587 * Decodes headers
 588 *
 589 * This functions decode strings that is encoded according to
 590 * RFC1522 (MIME Part Two: Message Header Extensions for Non-ASCII Text).
 591 * Patched by Christian Schmidt <christian@ostenfeld.dk>  23/03/2002
 592 *
 593 * @param string $string header string that has to be made readable
 594 * @param boolean $utfencode change message in order to be readable on user's charset. defaults to true
 595 * @param boolean $htmlsave preserve spaces and sanitize html special characters. defaults to true
 596 * @param boolean $decide decide if string can be utfencoded. defaults to false
 597 * @return string decoded header string
 598 */
 599 function decodeHeader ($string, $utfencode=true,$htmlsave=true,$decide=false) {
 600     global $languages, $squirrelmail_language,$default_charset;
 601     if (is_array($string)) {
 602         $string = implode("\n", $string);
 603     }
 604
 605     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 606         function_exists($languages[$squirrelmail_language]['XTRA_CODE'] . '_decodeheader')) {
 607         $string = call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_decodeheader', $string);
 608         // Do we need to return at this point?
 609         // return $string;
 610     }
 611     $i = 0;
 612     $iLastMatch = -2;
 613     $encoded = true;
 614
 615     $aString = explode(' ',$string);
 616     $ret = '';
 617     foreach ($aString as $chunk) {
 618         if ($encoded && $chunk === '') {
 619             continue;
 620         } elseif ($chunk === '') {
 621             $ret .= ' ';
 622             continue;
 623         }
 624         $encoded = false;
 625         /* if encoded words are not separated by a linear-space-white we still catch them */
 626         $j = $i-1;
 627
 628         while ($match = preg_match('/^(.*)=\?([^?]*)\?(Q|B)\?([^?]*)\?=(.*)$/Ui',$chunk,$res)) {
 629             /* if the last chunk isn't an encoded string then put back the space, otherwise don't */
 630             if ($iLastMatch !== $j) {
 631                 if ($htmlsave) {
 632                     $ret .= '&#32;';
 633                 } else {
 634                     $ret .= ' ';
 635                 }
 636             }
 637             $iLastMatch = $i;
 638             $j = $i;
 639             if ($htmlsave) {
 640                 $ret .= htmlspecialchars($res[1]);
 641             } else {
 642                 $ret .= $res[1];
 643             }
 644             $encoding = ucfirst($res[3]);
 645
 646             /* decide about valid decoding */
 647             if ($decide && is_conversion_safe($res[2])) {
 648             $utfencode=true;
 649             $can_be_encoded=true;
 650             } else {
 651             $can_be_encoded=false;
 652             }
 653             switch ($encoding)
 654             {
 655             case 'B':
 656                 $replace = base64_decode($res[4]);
 657                 if ($utfencode) {
 658                     if ($can_be_encoded) {
 659                         /* convert string to different charset,
 660                         * if functions asks for it (usually in compose)
 661                         */
 662                         $ret .= charset_convert($res[2],$replace,$default_charset);
 663                     } else {
 664                         // convert string to html codes in order to display it
 665                         $ret .= charset_decode($res[2],$replace);
 666                     }
 667                 } else {
 668                     if ($htmlsave) {
 669                         $replace = htmlspecialchars($replace);
 670                     }
 671                     $ret.= $replace;
 672                 }
 673                 break;
 674             case 'Q':
 675                 $replace = str_replace('_', ' ', $res[4]);
 676                 $replace = preg_replace('/=([0-9a-f]{2})/ie', 'chr(hexdec("\1"))',
 677                                     $replace);
 678                 if ($utfencode) {
 679                 if ($can_be_encoded) {
 680                     /* convert string to different charset,
 681                     * if functions asks for it (usually in compose)
 682                     */
 683                     $replace = charset_convert($res[2], $replace,$default_charset);
 684                 } else {
 685                     // convert string to html codes in order to display it
 686                     $replace = charset_decode($res[2], $replace);
 687                 }
 688                 } else {
 689                     if ($htmlsave) {
 690                         $replace = htmlspecialchars($replace);
 691                     }
 692                 }
 693                 $ret .= $replace;
 694                 break;
 695             default:
 696                 break;
 697             }
 698             $chunk = $res[5];
 699             $encoded = true;
 700         }
 701         if (!$encoded) {
 702             if ($htmlsave) {
 703                 $ret .= '&#32;';
 704             } else {
 705                 $ret .= ' ';
 706             }
 707         }
 708
 709         if (!$encoded && $htmlsave) {
 710             $ret .= htmlspecialchars($chunk);
 711         } else {
 712             $ret .= $chunk;
 713         }
 714         ++$i;
 715     }
 716     /* remove the first added space */
 717     if ($ret) {
 718         if ($htmlsave) {
 719             $ret = substr($ret,5);
 720         } else {
 721             $ret = substr($ret,1);
 722         }
 723     }
 724
 725     return $ret;
 726 }
 727
 728 /**
 729 * Encodes header as quoted-printable
 730 *
 731 * Encode a string according to RFC 1522 for use in headers if it
 732 * contains 8-bit characters or anything that looks like it should
 733 * be encoded.
 734 *
 735 * @param string $string header string, that has to be encoded
 736 * @return string quoted-printable encoded string
 737 */
 738 function encodeHeader ($string) {
 739     global $default_charset, $languages, $squirrelmail_language;
 740
 741     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 742         function_exists($languages[$squirrelmail_language]['XTRA_CODE'] . '_encodeheader')) {
 743         return  call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_encodeheader', $string);
 744     }
 745
 746     // Encode only if the string contains 8-bit characters or =?
 747     $j = strlen($string);
 748     $max_l = 75 - strlen($default_charset) - 7;
 749     $aRet = array();
 750     $ret = '';
 751     $iEncStart = $enc_init = false;
 752     $cur_l = $iOffset = 0;
 753     for($i = 0; $i < $j; ++$i) {
 754         switch($string{$i})
 755         {
 756         case '=':
 757         case '<':
 758         case '>':
 759         case ',':
 760         case '?':
 761         case '_':
 762             if ($iEncStart === false) {
 763                 $iEncStart = $i;
 764             }
 765             $cur_l+=3;
 766             if ($cur_l > ($max_l-2)) {
 767                 /* if there is an stringpart that doesn't need encoding, add it */
 768                 $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 769                 $aRet[] = "=?$default_charset?Q?$ret?=";
 770                 $iOffset = $i;
 771                 $cur_l = 0;
 772                 $ret = '';
 773                 $iEncStart = false;
 774             } else {
 775                 $ret .= sprintf("=%02X",ord($string{$i}));
 776             }
 777             break;
 778         case '(':
 779         case ')':
 780             if ($iEncStart !== false) {
 781                 $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 782                 $aRet[] = "=?$default_charset?Q?$ret?=";
 783                 $iOffset = $i;
 784                 $cur_l = 0;
 785                 $ret = '';
 786                 $iEncStart = false;
 787             }
 788             break;
 789         case ' ':
 790             if ($iEncStart !== false) {
 791                 $cur_l++;
 792                 if ($cur_l > $max_l) {
 793                     $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 794                     $aRet[] = "=?$default_charset?Q?$ret?=";
 795                     $iOffset = $i;
 796                     $cur_l = 0;
 797                     $ret = '';
 798                     $iEncStart = false;
 799                 } else {
 800                     $ret .= '_';
 801                 }
 802             }
 803             break;
 804         default:
 805             $k = ord($string{$i});
 806             if ($k > 126) {
 807                 if ($iEncStart === false) {
 808                     // do not start encoding in the middle of a string, also take the rest of the word.
 809                     $sLeadString = substr($string,0,$i);
 810                     $aLeadString = explode(' ',$sLeadString);
 811                     $sToBeEncoded = array_pop($aLeadString);
 812                     $iEncStart = $i - strlen($sToBeEncoded);
 813                     $ret .= $sToBeEncoded;
 814                     $cur_l += strlen($sToBeEncoded);
 815                 }
 816                 $cur_l += 3;
 817                 /* first we add the encoded string that reached it's max size */
 818                 if ($cur_l > ($max_l-2)) {
 819                     $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 820                     $aRet[] = "=?$default_charset?Q?$ret?= "; /* the next part is also encoded => separate by space */
 821                     $cur_l = 3;
 822                     $ret = '';
 823                     $iOffset = $i;
 824                     $iEncStart = $i;
 825                 }
 826                 $enc_init = true;
 827                 $ret .= sprintf("=%02X", $k);
 828             } else {
 829                 if ($iEncStart !== false) {
 830                     $cur_l++;
 831                     if ($cur_l > $max_l) {
 832                         $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 833                         $aRet[] = "=?$default_charset?Q?$ret?=";
 834                         $iEncStart = false;
 835                         $iOffset = $i;
 836                         $cur_l = 0;
 837                         $ret = '';
 838                     } else {
 839                         $ret .= $string{$i};
 840                     }
 841                 }
 842             }
 843             break;
 844         }
 845     }
 846
 847     if ($enc_init) {
 848         if ($iEncStart !== false) {
 849             $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 850             $aRet[] = "=?$default_charset?Q?$ret?=";
 851         } else {
 852             $aRet[] = substr($string,$iOffset);
 853         }
 854         $string = implode('',$aRet);
 855     }
 856     return $string;
 857 }
 858
 859 /* This function trys to locate the entity_id of a specific mime element */
 860 function find_ent_id($id, $message) {
 861     for ($i = 0, $ret = ''; $ret == '' && $i < count($message->entities); $i++) {
 862         if ($message->entities[$i]->header->type0 == 'multipart')  {
 863             $ret = find_ent_id($id, $message->entities[$i]);
 864         } else {
 865             if (strcasecmp($message->entities[$i]->header->id, $id) == 0) {
 866 //                if (sq_check_save_extension($message->entities[$i])) {
 867                     return $message->entities[$i]->entity_id;
 868 //                }
 869             } elseif (!empty($message->entities[$i]->header->parameters['name'])) {
 870                 /**
 871                  * This is part of a fix for Outlook Express 6.x generating
 872                  * cid URLs without creating content-id headers
 873                  * @@JA - 20050207
 874                  */
 875                 if (strcasecmp($message->entities[$i]->header->parameters['name'], $id) == 0) {
 876                     return $message->entities[$i]->entity_id;
 877                 }
 878             }
 879         }
 880     }
 881     return $ret;
 882 }
 883
 884 function sq_check_save_extension($message) {
 885     $filename = $message->getFilename();
 886     $ext = substr($filename, strrpos($filename,'.')+1);
 887     $save_extensions = array('jpg','jpeg','gif','png','bmp');
 888     return in_array($ext, $save_extensions);
 889 }
 890
 891
 892 /**
 893 ** HTMLFILTER ROUTINES
 894 */
 895
 896 /**
 897 * This function is more or less a wrapper around stripslashes. Apparently
 898 * Explorer is stupid enough to just remove the backslashes and then
 899 * execute the content of the attribute as if nothing happened.
 900 * Who does that?
 901 *
 902 * @param  attvalue   The value of the attribute
 903 * @return attvalue   The value of the attribute stripslashed.
 904 */
 905 function sq_unbackslash($attvalue){
 906     /**
 907     * Remove any backslashes. See if there are any first.
 908     */
 909
 910     if (strstr($attvalue, '\\') !== false){
 911         $attvalue = stripslashes($attvalue);
 912     }
 913     return $attvalue;
 914 }
 915
 916 /**
 917 * Kill any tabs, newlines, or carriage returns. Our friends the
 918 * makers of the browser with 95% market value decided that it'd
 919 * be funny to make "java[tab]script" be just as good as "javascript".
 920 *
 921 * @param  attvalue  The attribute value before extraneous spaces removed.
 922 * @return attvalue  The attribute value after extraneous spaces removed.
 923 */
 924 function sq_unspace($attvalue){
 925     if (strcspn($attvalue, "\t\r\n") != strlen($attvalue)){
 926         $attvalue = str_replace(Array("\t", "\r", "\n"), Array('', '', ''),
 927                                 $attvalue);
 928     }
 929     return $attvalue;
 930 }
 931
 932 /**
 933 * This function returns the final tag out of the tag name, an array
 934 * of attributes, and the type of the tag. This function is called by
 935 * sq_sanitize internally.
 936 *
 937 * @param  $tagname  the name of the tag.
 938 * @param  $attary   the array of attributes and their values
 939 * @param  $tagtype  The type of the tag (see in comments).
 940 * @return           a string with the final tag representation.
 941 */
 942 function sq_tagprint($tagname, $attary, $tagtype){
 943     $me = 'sq_tagprint';
 944
 945     if ($tagtype == 2){
 946         $fulltag = '</' . $tagname . '>';
 947     } else {
 948         $fulltag = '<' . $tagname;
 949         if (is_array($attary) && sizeof($attary)){
 950             $atts = Array();
 951             while (list($attname, $attvalue) = each($attary)){
 952                 array_push($atts, "$attname=$attvalue");
 953             }
 954             $fulltag .= ' ' . join(" ", $atts);
 955         }
 956         if ($tagtype == 3){
 957             $fulltag .= ' /';
 958         }
 959         $fulltag .= '>';
 960     }
 961     return $fulltag;
 962 }
 963
 964 /**
 965 * A small helper function to use with array_walk. Modifies a by-ref
 966 * value and makes it lowercase.
 967 *
 968 * @param  $val a value passed by-ref.
 969 * @return      void since it modifies a by-ref value.
 970 */
 971 function sq_casenormalize(&$val){
 972     $val = strtolower($val);
 973 }
 974
 975 /**
 976 * This function skips any whitespace from the current position within
 977 * a string and to the next non-whitespace value.
 978 *
 979 * @param  $body   the string
 980 * @param  $offset the offset within the string where we should start
 981 *                 looking for the next non-whitespace character.
 982 * @return         the location within the $body where the next
 983 *                 non-whitespace char is located.
 984 */
 985 function sq_skipspace($body, $offset){
 986     $me = 'sq_skipspace';
 987     preg_match('/^(\s*)/s', substr($body, $offset), $matches);
 988     if (sizeof($matches{1})){
 989         $count = strlen($matches{1});
 990         $offset += $count;
 991     }
 992     return $offset;
 993 }
 994
 995 /**
 996 * This function looks for the next character within a string.  It's
 997 * really just a glorified "strpos", except it catches if failures
 998 * nicely.
 999 *
1000 * @param  $body   The string to look for needle in.
1001 * @param  $offset Start looking from this position.
1002 * @param  $needle The character/string to look for.
1003 * @return         location of the next occurance of the needle, or
1004 *                 strlen($body) if needle wasn't found.
1005 */
1006 function sq_findnxstr($body, $offset, $needle){
1007     $me  = 'sq_findnxstr';
1008     $pos = strpos($body, $needle, $offset);
1009     if ($pos === FALSE){
1010         $pos = strlen($body);
1011     }
1012     return $pos;
1013 }
1014
1015 /**
1016 * This function takes a PCRE-style regexp and tries to match it
1017 * within the string.
1018 *
1019 * @param  $body   The string to look for needle in.
1020 * @param  $offset Start looking from here.
1021 * @param  $reg    A PCRE-style regex to match.
1022 * @return         Returns a false if no matches found, or an array
1023 *                 with the following members:
1024 *                 - integer with the location of the match within $body
1025 *                 - string with whatever content between offset and the match
1026 *                 - string with whatever it is we matched
1027 */
1028 function sq_findnxreg($body, $offset, $reg){
1029     $me = 'sq_findnxreg';
1030     $matches = Array();
1031     $retarr = Array();
1032     preg_match("%^(.*?)($reg)%si", substr($body, $offset), $matches);
1033     if (!isset($matches{0}) || !$matches{0}){
1034         $retarr = false;
1035     } else {
1036         $retarr{0} = $offset + strlen($matches{1});
1037         $retarr{1} = $matches{1};
1038         $retarr{2} = $matches{2};
1039     }
1040     return $retarr;
1041 }
1042
1043 /**
1044 * This function looks for the next tag.
1045 *
1046 * @param  $body   String where to look for the next tag.
1047 * @param  $offset Start looking from here.
1048 * @return         false if no more tags exist in the body, or
1049 *                 an array with the following members:
1050 *                 - string with the name of the tag
1051 *                 - array with attributes and their values
1052 *                 - integer with tag type (1, 2, or 3)
1053 *                 - integer where the tag starts (starting "<")
1054 *                 - integer where the tag ends (ending ">")
1055 *                 first three members will be false, if the tag is invalid.
1056 */
1057 function sq_getnxtag($body, $offset){
1058     $me = 'sq_getnxtag';
1059     if ($offset > strlen($body)){
1060         return false;
1061     }
1062     $lt = sq_findnxstr($body, $offset, "<");
1063     if ($lt == strlen($body)){
1064         return false;
1065     }
1066     /**
1067     * We are here:
1068     * blah blah <tag attribute="value">
1069     * \---------^
1070     */
1071     $pos = sq_skipspace($body, $lt+1);
1072     if ($pos >= strlen($body)){
1073         return Array(false, false, false, $lt, strlen($body));
1074     }
1075     /**
1076     * There are 3 kinds of tags:
1077     * 1. Opening tag, e.g.:
1078     *    <a href="blah">
1079     * 2. Closing tag, e.g.:
1080     *    </a>
1081     * 3. XHTML-style content-less tag, e.g.:
1082     *    <img src="blah" />
1083     */
1084     $tagtype = false;
1085     switch (substr($body, $pos, 1)){
1086         case '/':
1087             $tagtype = 2;
1088             $pos++;
1089             break;
1090         case '!':
1091             /**
1092             * A comment or an SGML declaration.
1093             */
1094             if (substr($body, $pos+1, 2) == "--"){
1095                 $gt = strpos($body, "-->", $pos);
1096                 if ($gt === false){
1097                     $gt = strlen($body);
1098                 } else {
1099                     $gt += 2;
1100                 }
1101                 return Array(false, false, false, $lt, $gt);
1102             } else {
1103                 $gt = sq_findnxstr($body, $pos, ">");
1104                 return Array(false, false, false, $lt, $gt);
1105             }
1106             break;
1107         default:
1108             /**
1109             * Assume tagtype 1 for now. If it's type 3, we'll switch values
1110             * later.
1111             */
1112             $tagtype = 1;
1113             break;
1114     }
1115
1116     $tagname = '';
1117     /**
1118     * Look for next [\W-_], which will indicate the end of the tag name.
1119     */
1120     $regary = sq_findnxreg($body, $pos, "[^\w\-_]");
1121     if ($regary == false){
1122         return Array(false, false, false, $lt, strlen($body));
1123     }
1124     list($pos, $tagname, $match) = $regary;
1125     $tagname = strtolower($tagname);
1126
1127     /**
1128     * $match can be either of these:
1129     * '>'  indicating the end of the tag entirely.
1130     * '\s' indicating the end of the tag name.
1131     * '/'  indicating that this is type-3 xhtml tag.
1132     *
1133     * Whatever else we find there indicates an invalid tag.
1134     */
1135     switch ($match){
1136         case '/':
1137             /**
1138             * This is an xhtml-style tag with a closing / at the
1139             * end, like so: <img src="blah" />. Check if it's followed
1140             * by the closing bracket. If not, then this tag is invalid
1141             */
1142             if (substr($body, $pos, 2) == "/>"){
1143                 $pos++;
1144                 $tagtype = 3;
1145             } else {
1146                 $gt = sq_findnxstr($body, $pos, ">");
1147                 $retary = Array(false, false, false, $lt, $gt);
1148                 return $retary;
1149             }
1150         case '>':
1151             return Array($tagname, false, $tagtype, $lt, $pos);
1152             break;
1153         default:
1154             /**
1155             * Check if it's whitespace
1156             */
1157             if (!preg_match('/\s/', $match)){
1158                 /**
1159                 * This is an invalid tag! Look for the next closing ">".
1160                 */
1161                 $gt = sq_findnxstr($body, $lt, ">");
1162                 return Array(false, false, false, $lt, $gt);
1163             }
1164             break;
1165     }
1166
1167     /**
1168     * At this point we're here:
1169     * <tagname  attribute='blah'>
1170     * \-------^
1171     *
1172     * At this point we loop in order to find all attributes.
1173     */
1174     $attname = '';
1175     $attary = Array();
1176
1177     while ($pos <= strlen($body)){
1178         $pos = sq_skipspace($body, $pos);
1179         if ($pos == strlen($body)){
1180             /**
1181             * Non-closed tag.
1182             */
1183             return Array(false, false, false, $lt, $pos);
1184         }
1185         /**
1186         * See if we arrived at a ">" or "/>", which means that we reached
1187         * the end of the tag.
1188         */
1189         $matches = Array();
1190         if (preg_match("%^(\s*)(>|/>)%s", substr($body, $pos), $matches)) {
1191             /**
1192             * Yep. So we did.
1193             */
1194             $pos += strlen($matches{1});
1195             if ($matches{2} == "/>"){
1196                 $tagtype = 3;
1197                 $pos++;
1198             }
1199             return Array($tagname, $attary, $tagtype, $lt, $pos);
1200         }
1201
1202         /**
1203         * There are several types of attributes, with optional
1204         * [:space:] between members.
1205         * Type 1:
1206         *   attrname[:space:]=[:space:]'CDATA'
1207         * Type 2:
1208         *   attrname[:space:]=[:space:]"CDATA"
1209         * Type 3:
1210         *   attr[:space:]=[:space:]CDATA
1211         * Type 4:
1212         *   attrname
1213         *
1214         * We leave types 1 and 2 the same, type 3 we check for
1215         * '"' and convert to "&quot" if needed, then wrap in
1216         * double quotes. Type 4 we convert into:
1217         * attrname="yes".
1218         */
1219         $regary = sq_findnxreg($body, $pos, "[^:\w\-_]");
1220         if ($regary == false){
1221             /**
1222             * Looks like body ended before the end of tag.
1223             */
1224             return Array(false, false, false, $lt, strlen($body));
1225         }
1226         list($pos, $attname, $match) = $regary;
1227         $attname = strtolower($attname);
1228         /**
1229         * We arrived at the end of attribute name. Several things possible
1230         * here:
1231         * '>'  means the end of the tag and this is attribute type 4
1232         * '/'  if followed by '>' means the same thing as above
1233         * '\s' means a lot of things -- look what it's followed by.
1234         *      anything else means the attribute is invalid.
1235         */
1236         switch($match){
1237             case '/':
1238                 /**
1239                 * This is an xhtml-style tag with a closing / at the
1240                 * end, like so: <img src="blah" />. Check if it's followed
1241                 * by the closing bracket. If not, then this tag is invalid
1242                 */
1243                 if (substr($body, $pos, 2) == "/>"){
1244                     $pos++;
1245                     $tagtype = 3;
1246                 } else {
1247                     $gt = sq_findnxstr($body, $pos, ">");
1248                     $retary = Array(false, false, false, $lt, $gt);
1249                     return $retary;
1250                 }
1251             case '>':
1252                 $attary{$attname} = '"yes"';
1253                 return Array($tagname, $attary, $tagtype, $lt, $pos);
1254                 break;
1255             default:
1256                 /**
1257                 * Skip whitespace and see what we arrive at.
1258                 */
1259                 $pos = sq_skipspace($body, $pos);
1260                 $char = substr($body, $pos, 1);
1261                 /**
1262                 * Two things are valid here:
1263                 * '=' means this is attribute type 1 2 or 3.
1264                 * \w means this was attribute type 4.
1265                 * anything else we ignore and re-loop. End of tag and
1266                 * invalid stuff will be caught by our checks at the beginning
1267                 * of the loop.
1268                 */
1269                 if ($char == "="){
1270                     $pos++;
1271                     $pos = sq_skipspace($body, $pos);
1272                     /**
1273                     * Here are 3 possibilities:
1274                     * "'"  attribute type 1
1275                     * '"'  attribute type 2
1276                     * everything else is the content of tag type 3
1277                     */
1278                     $quot = substr($body, $pos, 1);
1279                     if ($quot == "'"){
1280                         $regary = sq_findnxreg($body, $pos+1, "\'");
1281                         if ($regary == false){
1282                             return Array(false, false, false, $lt, strlen($body));
1283                         }
1284                         list($pos, $attval, $match) = $regary;
1285                         $pos++;
1286                         $attary{$attname} = "'" . $attval . "'";
1287                     } else if ($quot == '"'){
1288                         $regary = sq_findnxreg($body, $pos+1, '\"');
1289                         if ($regary == false){
1290                             return Array(false, false, false, $lt, strlen($body));
1291                         }
1292                         list($pos, $attval, $match) = $regary;
1293                         $pos++;
1294                         $attary{$attname} = '"' . $attval . '"';
1295                     } else {
1296                         /**
1297                         * These are hateful. Look for \s, or >.
1298                         */
1299                         $regary = sq_findnxreg($body, $pos, "[\s>]");
1300                         if ($regary == false){
1301                             return Array(false, false, false, $lt, strlen($body));
1302                         }
1303                         list($pos, $attval, $match) = $regary;
1304                         /**
1305                         * If it's ">" it will be caught at the top.
1306                         */
1307                         $attval = preg_replace("/\"/s", "&quot;", $attval);
1308                         $attary{$attname} = '"' . $attval . '"';
1309                     }
1310                 } else if (preg_match("|[\w/>]|", $char)) {
1311                     /**
1312                     * That was attribute type 4.
1313                     */
1314                     $attary{$attname} = '"yes"';
1315                 } else {
1316                     /**
1317                     * An illegal character. Find next '>' and return.
1318                     */
1319                     $gt = sq_findnxstr($body, $pos, ">");
1320                     return Array(false, false, false, $lt, $gt);
1321                 }
1322                 break;
1323         }
1324     }
1325     /**
1326     * The fact that we got here indicates that the tag end was never
1327     * found. Return invalid tag indication so it gets stripped.
1328     */
1329     return Array(false, false, false, $lt, strlen($body));
1330 }
1331
1332 /**
1333 * This function checks attribute values for entity-encoded values
1334 * and returns them translated into 8-bit strings so we can run
1335 * checks on them.
1336 *
1337 * @param  $attvalue A string to run entity check against.
1338 * @return           Translated value.
1339 */
1340
1341 function sq_deent($attvalue){
1342     $me = 'sq_deent';
1343     /**
1344     * See if we have to run the checks first. All entities must start
1345     * with "&".
1346     */
1347     if (strpos($attvalue, '&') === false){
1348         return $attvalue;
1349     }
1350     /**
1351     * Check named entities first.
1352     */
1353     $trans = get_html_translation_table(HTML_ENTITIES);
1354     /**
1355     * Leave &quot; in, as it can mess us up.
1356     */
1357     $trans = array_flip($trans);
1358     unset($trans{'&quot;'});
1359     while (list($ent, $val) = each($trans)){
1360         $attvalue = preg_replace('/' . $ent . '*/si', $val, $attvalue);
1361     }
1362     /**
1363     * Now translate numbered entities from 1 to 255 if needed.
1364     */
1365     if (strpos($attvalue, '#') !== false){
1366         $omit = Array(34, 39);
1367         for ($asc = 256; $asc >= 0; $asc--){
1368             if (!in_array($asc, $omit)){
1369                 $chr = chr($asc);
1370                 $octrule = '/\&#0*' . $asc . ';*/si';
1371                 $hexrule = '/\&#x0*' . dechex($asc) . ';*/si';
1372                 $attvalue = preg_replace($octrule, $chr, $attvalue);
1373                 $attvalue = preg_replace($hexrule, $chr, $attvalue);
1374             }
1375         }
1376     }
1377     return $attvalue;
1378 }
1379
1380 /**
1381 * This function runs various checks against the attributes.
1382 *
1383 * @param  $tagname         String with the name of the tag.
1384 * @param  $attary          Array with all tag attributes.
1385 * @param  $rm_attnames     See description for sq_sanitize
1386 * @param  $bad_attvals     See description for sq_sanitize
1387 * @param  $add_attr_to_tag See description for sq_sanitize
1388 * @param  $message         message object
1389 * @param  $id              message id
1390 * @return                  Array with modified attributes.
1391 */
1392 function sq_fixatts($tagname,
1393                     $attary,
1394                     $rm_attnames,
1395                     $bad_attvals,
1396                     $add_attr_to_tag,
1397                     $message,
1398                     $id,
1399                     $mailbox
1400                     ){
1401     $me = 'sq_fixatts';
1402     while (list($attname, $attvalue) = each($attary)){
1403         /**
1404         * See if this attribute should be removed.
1405         */
1406         foreach ($rm_attnames as $matchtag=>$matchattrs){
1407             if (preg_match($matchtag, $tagname)){
1408                 foreach ($matchattrs as $matchattr){
1409                     if (preg_match($matchattr, $attname)){
1410                         unset($attary{$attname});
1411                         continue;
1412                     }
1413                 }
1414             }
1415         }
1416         /**
1417         * Remove any backslashes, entities, and extraneous whitespace.
1418         */
1419         $attvalue = sq_unbackslash($attvalue);
1420         $attvalue = sq_deent($attvalue);
1421         $attvalue = sq_unspace($attvalue);
1422
1423         /**
1424         * Remove \r \n \t \0 " " "\\"
1425         */
1426         $attvalue = str_replace(Array("\r", "\n", "\t", "\0", " ", "\\"),
1427                         Array('', '','','','',''), $attvalue);
1428
1429         /**
1430         * Now let's run checks on the attvalues.
1431         * I don't expect anyone to comprehend this. If you do,
1432         * get in touch with me so I can drive to where you live and
1433         * shake your hand personally. :)
1434         */
1435         foreach ($bad_attvals as $matchtag=>$matchattrs){
1436             if (preg_match($matchtag, $tagname)){
1437                 foreach ($matchattrs as $matchattr=>$valary){
1438                     if (preg_match($matchattr, $attname)){
1439                         /**
1440                         * There are two arrays in valary.
1441                         * First is matches.
1442                         * Second one is replacements
1443                         */
1444                         list($valmatch, $valrepl) = $valary;
1445                         $newvalue =
1446                             preg_replace($valmatch, $valrepl, $attvalue);
1447                         if ($newvalue != $attvalue){
1448                             $attary{$attname} = $newvalue;
1449                         }
1450                     }
1451                 }
1452             }
1453         }
1454         /**
1455         * Turn cid: urls into http-friendly ones.
1456         */
1457         if (preg_match("/^[\'\"]\s*cid:/si", $attvalue)){
1458             $attary{$attname} = sq_cid2http($message, $id, $attvalue, $mailbox);
1459         }
1460     }
1461     /**
1462     * See if we need to append any attributes to this tag.
1463     */
1464     foreach ($add_attr_to_tag as $matchtag=>$addattary){
1465         if (preg_match($matchtag, $tagname)){
1466             $attary = array_merge($attary, $addattary);
1467         }
1468     }
1469     return $attary;
1470 }
1471
1472 /**
1473 * This function edits the style definition to make them friendly and
1474 * usable in SquirrelMail.
1475 *
1476 * @param  $message  the message object
1477 * @param  $id       the message id
1478 * @param  $content  a string with whatever is between <style> and </style>
1479 * @param  $mailbox  the message mailbox
1480 * @return           a string with edited content.
1481 */
1482 function sq_fixstyle($body, $pos, $message, $id, $mailbox){
1483     global $view_unsafe_images;
1484     $me = 'sq_fixstyle';
1485     $ret = sq_findnxreg($body, $pos, '</\s*style\s*>');
1486     if ($ret == FALSE){
1487         return array(FALSE, strlen($body));
1488     }
1489     $newpos = $ret[0] + strlen($ret[2]);
1490     $content = $ret[1];
1491     /**
1492     * First look for general BODY style declaration, which would be
1493     * like so:
1494     * body {background: blah-blah}
1495     * and change it to .bodyclass so we can just assign it to a <div>
1496     */
1497     $content = preg_replace("|body(\s*\{.*?\})|si", ".bodyclass\\1", $content);
1498     $secremoveimg = '../images/' . _("sec_remove_eng.png");
1499     /**
1500     * Fix url('blah') declarations.
1501     */
1502     $content = preg_replace("|url\s*\(\s*([\'\"])\s*\S+script\s*:.*?([\'\"])\s*\)|si",
1503                             "url(\\1$secremoveimg\\2)", $content);
1504     /**
1505     * Fix url('https*://.*) declarations but only if $view_unsafe_images
1506     * is false.
1507     */
1508     if (!$view_unsafe_images){
1509         $content = preg_replace("|url\s*\(\s*([\'\"])\s*https*:.*?([\'\"])\s*\)|si",
1510                                 "url(\\1$secremoveimg\\2)", $content);
1511     }
1512
1513     /**
1514     * Fix urls that refer to cid:
1515     */
1516     while (preg_match("|url\s*\(\s*([\'\"]\s*cid:.*?[\'\"])\s*\)|si",
1517                     $content, $matches)){
1518         $cidurl = $matches{1};
1519         $httpurl = sq_cid2http($message, $id, $cidurl, $mailbox);
1520         $content = preg_replace("|url\s*\(\s*$cidurl\s*\)|si",
1521                                 "url($httpurl)", $content);
1522     }
1523
1524     /**
1525     * Fix stupid css declarations which lead to vulnerabilities
1526     * in IE.
1527     */
1528     $match   = Array('/expression/i',
1529                     '/behaviou*r/i',
1530                     '/binding/i',
1531                     '/include-source/i');
1532     $replace = Array('idiocy', 'idiocy', 'idiocy', 'idiocy');
1533     $content = preg_replace($match, $replace, $content);
1534     return array($content, $newpos);
1535 }
1536
1537 /**
1538 * This function converts cid: url's into the ones that can be viewed in
1539 * the browser.
1540 *
1541 * @param  $message  the message object
1542 * @param  $id       the message id
1543 * @param  $cidurl   the cid: url.
1544 * @param  $mailbox  the message mailbox
1545 * @return           a string with a http-friendly url
1546 */
1547 function sq_cid2http($message, $id, $cidurl, $mailbox){
1548     /**
1549     * Get rid of quotes.
1550     */
1551     $quotchar = substr($cidurl, 0, 1);
1552     if ($quotchar == '"' || $quotchar == "'"){
1553         $cidurl = str_replace($quotchar, "", $cidurl);
1554     } else {
1555         $quotchar = '';
1556     }
1557     $cidurl = substr(trim($cidurl), 4);
1558     $linkurl = find_ent_id($cidurl, $message);
1559     /* in case of non-save cid links $httpurl should be replaced by a sort of
1560     unsave link image */
1561     $httpurl = '';
1562
1563    /**
1564     * This is part of a fix for Outlook Express 6.x generating
1565     * cid URLs without creating content-id headers. These images are
1566     * not part of the multipart/related html mail. The html contains
1567     * <img src="cid:{some_id}/image_filename.ext"> references to
1568     * attached images with as goal to render them inline although
1569     * the attachment disposition property is not inline.
1570     **/
1571
1572     if (empty($linkurl)) {
1573         if (preg_match('/{.*}\//', $cidurl)) {
1574             $cidurl = preg_replace('/{.*}\//','', $cidurl);
1575             if (!empty($cidurl)) {
1576                 $linkurl = find_ent_id($cidurl, $message);
1577             }
1578         }
1579     }
1580
1581     if (!empty($linkurl)) {
1582         $httpurl = $quotchar . SM_PATH . 'src/download.php?absolute_dl=true&amp;' .
1583                    "passed_id=$id&amp;mailbox=" . urlencode($mailbox) .
1584                    '&amp;ent_id=' . $linkurl . $quotchar;
1585     } else {
1586         /**
1587          * If we couldn't generate a proper img url, drop in a blank image
1588          * instead of sending back empty, otherwise it causes unusual behaviour
1589          */
1590         $httpurl = $quotechar . SM_PATH . 'images/blank.png';
1591     }
1592
1593     return $httpurl;
1594 }
1595
1596 /**
1597 * This function changes the <body> tag into a <div> tag since we
1598 * can't really have a body-within-body.
1599 *
1600 * @param  $attary   an array of attributes and values of <body>
1601 * @param  $mailbox  mailbox we're currently reading (for cid2http)
1602 * @param  $message  current message (for cid2http)
1603 * @param  $id       current message id (for cid2http)
1604 * @return           a modified array of attributes to be set for <div>
1605 */
1606 function sq_body2div($attary, $mailbox, $message, $id){
1607     $me = 'sq_body2div';
1608     $divattary = Array('class' => "'bodyclass'");
1609     $text = '#000000';
1610     $has_bgc_stl = $has_txt_stl = false;
1611     $styledef = '';
1612     if (is_array($attary) && sizeof($attary) > 0){
1613         foreach ($attary as $attname=>$attvalue){
1614             $quotchar = substr($attvalue, 0, 1);
1615             $attvalue = str_replace($quotchar, "", $attvalue);
1616             switch ($attname){
1617                 case 'background':
1618                     $attvalue = sq_cid2http($message, $id,
1619                                             $attvalue, $mailbox);
1620                     $styledef .= "background-image: url('$attvalue'); ";
1621                     break;
1622                 case 'bgcolor':
1623                     $has_bgc_stl = true;
1624                     $styledef .= "background-color: $attvalue; ";
1625                     break;
1626                 case 'text':
1627                     $has_txt_stl = true;
1628                     $styledef .= "color: $attvalue; ";
1629                     break;
1630             }
1631         }
1632         // Outlook defines a white bgcolor and no text color. This can lead to
1633         // white text on a white bg with certain themes.
1634         if ($has_bgc_stl && !$has_txt_stl) {
1635             $styledef .= "color: $text; ";
1636         }
1637         if (strlen($styledef) > 0){
1638             $divattary{"style"} = "\"$styledef\"";
1639         }
1640     }
1641     return $divattary;
1642 }
1643
1644 /**
1645 * This is the main function and the one you should actually be calling.
1646 * There are several variables you should be aware of an which need
1647 * special description.
1648 *
1649 * Since the description is quite lengthy, see it here:
1650 * http://linux.duke.edu/projects/mini/htmlfilter/
1651 *
1652 * @param $body                 the string with HTML you wish to filter
1653 * @param $tag_list             see description above
1654 * @param $rm_tags_with_content see description above
1655 * @param $self_closing_tags    see description above
1656 * @param $force_tag_closing    see description above
1657 * @param $rm_attnames          see description above
1658 * @param $bad_attvals          see description above
1659 * @param $add_attr_to_tag      see description above
1660 * @param $message              message object
1661 * @param $id                   message id
1662 * @return                      sanitized html safe to show on your pages.
1663 */
1664 function sq_sanitize($body,
1665                     $tag_list,
1666                     $rm_tags_with_content,
1667                     $self_closing_tags,
1668                     $force_tag_closing,
1669                     $rm_attnames,
1670                     $bad_attvals,
1671                     $add_attr_to_tag,
1672                     $message,
1673                     $id,
1674                     $mailbox
1675                     ){
1676     $me = 'sq_sanitize';
1677     $rm_tags = array_shift($tag_list);
1678     /**
1679     * Normalize rm_tags and rm_tags_with_content.
1680     */
1681     @array_walk($tag_list, 'sq_casenormalize');
1682     @array_walk($rm_tags_with_content, 'sq_casenormalize');
1683     @array_walk($self_closing_tags, 'sq_casenormalize');
1684     /**
1685     * See if tag_list is of tags to remove or tags to allow.
1686     * false  means remove these tags
1687     * true   means allow these tags
1688     */
1689     $curpos = 0;
1690     $open_tags = Array();
1691     $trusted = "\n<!-- begin sanitized html -->\n";
1692     $skip_content = false;
1693     /**
1694     * Take care of netscape's stupid javascript entities like
1695     * &{alert('boo')};
1696     */
1697     $body = preg_replace("/&(\{.*?\};)/si", "&amp;\\1", $body);
1698
1699     while (($curtag = sq_getnxtag($body, $curpos)) != FALSE){
1700         list($tagname, $attary, $tagtype, $lt, $gt) = $curtag;
1701         $free_content = substr($body, $curpos, $lt-$curpos);
1702         /**
1703         * Take care of <style>
1704         */
1705         if ($tagname == "style" && $tagtype == 1){
1706             list($free_content, $curpos) =
1707                 sq_fixstyle($body, $gt+1, $message, $id, $mailbox);
1708             if ($free_content != FALSE){
1709                 $trusted .= sq_tagprint($tagname, $attary, $tagtype);
1710                 $trusted .= $free_content;
1711                 $trusted .= sq_tagprint($tagname, false, 2);
1712             }
1713             continue;
1714         }
1715         if ($skip_content == false){
1716             $trusted .= $free_content;
1717         }
1718         if ($tagname != FALSE){
1719             if ($tagtype == 2){
1720                 if ($skip_content == $tagname){
1721                     /**
1722                     * Got to the end of tag we needed to remove.
1723                     */
1724                     $tagname = false;
1725                     $skip_content = false;
1726                 } else {
1727                     if ($skip_content == false){
1728                         if ($tagname == "body"){
1729                             $tagname = "div";
1730                         }
1731                         if (isset($open_tags{$tagname}) &&
1732                             $open_tags{$tagname} > 0){
1733                             $open_tags{$tagname}--;
1734                         } else {
1735                             $tagname = false;
1736                         }
1737                     }
1738                 }
1739             } else {
1740                 /**
1741                 * $rm_tags_with_content
1742                 */
1743                 if ($skip_content == false){
1744                     /**
1745                     * See if this is a self-closing type and change
1746                     * tagtype appropriately.
1747                     */
1748                     if ($tagtype == 1
1749                         && in_array($tagname, $self_closing_tags)){
1750                         $tagtype = 3;
1751                     }
1752                     /**
1753                     * See if we should skip this tag and any content
1754                     * inside it.
1755                     */
1756                     if ($tagtype == 1 &&
1757                         in_array($tagname, $rm_tags_with_content)){
1758                         $skip_content = $tagname;
1759                     } else {
1760                         if (($rm_tags == false
1761                             && in_array($tagname, $tag_list)) ||
1762                             ($rm_tags == true &&
1763                             !in_array($tagname, $tag_list))){
1764                             $tagname = false;
1765                         } else {
1766                             /**
1767                             * Convert body into div.
1768                             */
1769                             if ($tagname == "body"){
1770                                 $tagname = "div";
1771                                 $attary = sq_body2div($attary, $mailbox,
1772                                                     $message, $id);
1773                             }
1774                             if ($tagtype == 1){
1775                                 if (isset($open_tags{$tagname})){
1776                                     $open_tags{$tagname}++;
1777                                 } else {
1778                                     $open_tags{$tagname}=1;
1779                                 }
1780                             }
1781                             /**
1782                             * This is where we run other checks.
1783                             */
1784                             if (is_array($attary) && sizeof($attary) > 0){
1785                                 $attary = sq_fixatts($tagname,
1786                                                     $attary,
1787                                                     $rm_attnames,
1788                                                     $bad_attvals,
1789                                                     $add_attr_to_tag,
1790                                                     $message,
1791                                                     $id,
1792                                                     $mailbox
1793                                                     );
1794                             }
1795                         }
1796                     }
1797                 }
1798             }
1799             if ($tagname != false && $skip_content == false){
1800                 $trusted .= sq_tagprint($tagname, $attary, $tagtype);
1801             }
1802         }
1803         $curpos = $gt+1;
1804     }
1805     $trusted .= substr($body, $curpos, strlen($body)-$curpos);
1806     if ($force_tag_closing == true){
1807         foreach ($open_tags as $tagname=>$opentimes){
1808             while ($opentimes > 0){
1809                 $trusted .= '</' . $tagname . '>';
1810                 $opentimes--;
1811             }
1812         }
1813         $trusted .= "\n";
1814     }
1815     $trusted .= "<!-- end sanitized html -->\n";
1816     return $trusted;
1817 }
1818
1819 /**
1820 * This is a wrapper function to call html sanitizing routines.
1821 *
1822 * @param  $body  the body of the message
1823 * @param  $id    the id of the message
1824 * @return        a string with html safe to display in the browser.
1825 */
1826 function magicHTML($body, $id, $message, $mailbox = 'INBOX') {
1827     global $attachment_common_show_images, $view_unsafe_images,
1828         $has_unsafe_images;
1829     /**
1830     * Don't display attached images in HTML mode.
1831     */
1832     $attachment_common_show_images = false;
1833     $tag_list = Array(
1834                     false,
1835                     "object",
1836                     "meta",
1837                     "html",
1838                     "head",
1839                     "base",
1840                     "link",
1841                     "frame",
1842                     "iframe",
1843                     "plaintext",
1844                     "marquee"
1845                     );
1846
1847     $rm_tags_with_content = Array(
1848                                 "script",
1849                                 "applet",
1850                                 "embed",
1851                                 "title",
1852                                 "frameset",
1853                                 "xml"
1854                                 );
1855
1856     $self_closing_tags =  Array(
1857                                 "img",
1858                                 "br",
1859                                 "hr",
1860                                 "input"
1861                                 );
1862
1863     $force_tag_closing = true;
1864
1865     $rm_attnames = Array(
1866                         "/.*/" =>
1867                         Array(
1868                             "/target/i",
1869                             "/^on.*/i",
1870                             "/^dynsrc/i",
1871                             "/^data.*/i",
1872                             "/^lowsrc.*/i"
1873                             )
1874                         );
1875
1876     $secremoveimg = "../images/" . _("sec_remove_eng.png");
1877     $bad_attvals = Array(
1878         "/.*/" =>
1879             Array(
1880                 "/^src|background/i" =>
1881                     Array(
1882                         Array(
1883                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1884                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1885                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1886                                 ),
1887                         Array(
1888                                 "\\1$secremoveimg\\2",
1889                                 "\\1$secremoveimg\\2",
1890                                 "\\1$secremoveimg\\2",
1891                                 "\\1$secremoveimg\\2"
1892                                 )
1893                         ),
1894                 "/^href|action/i" =>
1895                     Array(
1896                         Array(
1897                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1898                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1899                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1900                                 ),
1901                         Array(
1902                                 "\\1#\\1",
1903                                 "\\1#\\1",
1904                                 "\\1#\\1",
1905                                 "\\1#\\1"
1906                                 )
1907                         ),
1908                 "/^style/i" =>
1909                     Array(
1910                         Array(
1911                                 "/expression/i",
1912                                 "/binding/i",
1913                                 "/behaviou*r/i",
1914                                 "/include-source/i",
1915                                 "/url\s*\(\s*([\'\"])\s*\S+script\s*:.*([\'\"])\s*\)/si",
1916                                 "/url\s*\(\s*([\'\"])\s*mocha\s*:.*([\'\"])\s*\)/si",
1917                                 "/url\s*\(\s*([\'\"])\s*about\s*:.*([\'\"])\s*\)/si",
1918                                 "/(.*)\s*:\s*url\s*\(\s*([\'\"]*)\s*\S+script\s*:.*([\'\"]*)\s*\)/si"
1919                             ),
1920                         Array(
1921                                 "idiocy",
1922                                 "idiocy",
1923                                 "idiocy",
1924                                 "idiocy",
1925                                 "url(\\1#\\1)",
1926                                 "url(\\1#\\1)",
1927                                 "url(\\1#\\1)",
1928                                 "url(\\1#\\1)",
1929                                 "\\1:url(\\2#\\3)"
1930                             )
1931                         )
1932                 )
1933         );
1934     if( !sqgetGlobalVar('view_unsafe_images', $view_unsafe_images, SQ_GET) ) {
1935         $view_unsafe_images = false;
1936     }
1937     if (!$view_unsafe_images){
1938         /**
1939         * Remove any references to http/https if view_unsafe_images set
1940         * to false.
1941         */
1942         array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[0],
1943                     '/^([\'\"])\s*https*:.*([\'\"])/si');
1944         array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[1],
1945                     "\\1$secremoveimg\\1");
1946         array_push($bad_attvals{'/.*/'}{'/^style/i'}[0],
1947                     '/url\(([\'\"])\s*https*:.*([\'\"])\)/si');
1948         array_push($bad_attvals{'/.*/'}{'/^style/i'}[1],
1949                     "url(\\1$secremoveimg\\1)");
1950     }
1951
1952     $add_attr_to_tag = Array(
1953         "/^a$/i" =>
1954             Array('target'=>'"_new"',
1955                 'title'=>'"'._("This external link will open in a new window").'"'
1956             )
1957     );
1958     $trusted = sq_sanitize($body,
1959                         $tag_list,
1960                         $rm_tags_with_content,
1961                         $self_closing_tags,
1962                         $force_tag_closing,
1963                         $rm_attnames,
1964                         $bad_attvals,
1965                         $add_attr_to_tag,
1966                         $message,
1967                         $id,
1968                         $mailbox
1969                         );
1970     if (preg_match("|$secremoveimg|i", $trusted)){
1971         $has_unsafe_images = true;
1972     }
1973     return $trusted;
1974 }
1975
1976 /**
1977 * function SendDownloadHeaders - send file to the browser
1978 *
1979 * Original Source: SM core src/download.php
1980 * moved here to make it available to other code, and separate
1981 * front end from back end functionality.
1982 *
1983 * @param string $type0 first half of mime type
1984 * @param string $type1 second half of mime type
1985 * @param string $filename filename to tell the browser for downloaded file
1986 * @param boolean $force whether to force the download dialog to pop
1987 * @param optional integer $filesize send the Content-Header and length to the browser
1988 * @return void
1989 */
1990 function SendDownloadHeaders($type0, $type1, $filename, $force, $filesize=0) {
1991     global $languages, $squirrelmail_language;
1992     $isIE = $isIE6 = 0;
1993
1994     sqgetGlobalVar('HTTP_USER_AGENT', $HTTP_USER_AGENT, SQ_SERVER);
1995
1996     if (strstr($HTTP_USER_AGENT, 'compatible; MSIE ') !== false &&
1997         strstr($HTTP_USER_AGENT, 'Opera') === false) {
1998         $isIE = 1;
1999     }
2000
2001     if (strstr($HTTP_USER_AGENT, 'compatible; MSIE 6') !== false &&
2002         strstr($HTTP_USER_AGENT, 'Opera') === false) {
2003         $isIE6 = 1;
2004     }
2005
2006     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
2007         function_exists($languages[$squirrelmail_language]['XTRA_CODE'] . '_downloadfilename')) {
2008         $filename =
2009         call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_downloadfilename', $filename, $HTTP_USER_AGENT);
2010     } else {
2011         $filename = ereg_replace('[\\/:\*\?"<>\|;]', '_', str_replace('&nbsp;', ' ', $filename));
2012     }
2013
2014     // A Pox on Microsoft and it's Internet Explorer!
2015     //
2016     // IE has lots of bugs with file downloads.
2017     // It also has problems with SSL.  Both of these cause problems
2018     // for us in this function.
2019     //
2020     // See this article on Cache Control headers and SSL
2021     // http://support.microsoft.com/default.aspx?scid=kb;en-us;323308
2022     //
2023     // The best thing you can do for IE is to upgrade to the latest
2024     // version
2025     //set all the Cache Control Headers for IE
2026     if ($isIE) {
2027         $filename=rawurlencode($filename);
2028         header ("Pragma: public");
2029         header ("Cache-Control: no-store, max-age=0, no-cache, must-revalidate"); # HTTP/1.1
2030         header ("Cache-Control: post-check=0, pre-check=0", false);
2031         header ("Cache-control: private");
2032
2033         //set the inline header for IE, we'll add the attachment header later if we need it
2034         header ("Content-Disposition: inline; filename=$filename");
2035     }
2036
2037     if (!$force) {
2038         // Try to show in browser window
2039         header ("Content-Disposition: inline; filename=\"$filename\"");
2040         header ("Content-Type: $type0/$type1; name=\"$filename\"");
2041     } else {
2042         // Try to pop up the "save as" box
2043
2044         // IE makes this hard.  It pops up 2 save boxes, or none.
2045         // http://support.microsoft.com/support/kb/articles/Q238/5/88.ASP
2046         // http://support.microsoft.com/default.aspx?scid=kb;EN-US;260519
2047         // But, according to Microsoft, it is "RFC compliant but doesn't
2048         // take into account some deviations that allowed within the
2049         // specification."  Doesn't that mean RFC non-compliant?
2050         // http://support.microsoft.com/support/kb/articles/Q258/4/52.ASP
2051
2052         // all browsers need the application/octet-stream header for this
2053         header ("Content-Type: application/octet-stream; name=\"$filename\"");
2054
2055         // http://support.microsoft.com/support/kb/articles/Q182/3/15.asp
2056         // Do not have quotes around filename, but that applied to
2057         // "attachment"... does it apply to inline too?
2058         header ("Content-Disposition: attachment; filename=\"$filename\"");
2059
2060         if ($isIE && !$isIE6) {
2061             // This combination seems to work mostly.  IE 5.5 SP 1 has
2062             // known issues (see the Microsoft Knowledge Base)
2063
2064             // This works for most types, but doesn't work with Word files
2065             header ("Content-Type: application/download; name=\"$filename\"");
2066
2067             // These are spares, just in case.  :-)
2068             //header("Content-Type: $type0/$type1; name=\"$filename\"");
2069             //header("Content-Type: application/x-msdownload; name=\"$filename\"");
2070             //header("Content-Type: application/octet-stream; name=\"$filename\"");
2071         } else {
2072             // another application/octet-stream forces download for Netscape
2073             header ("Content-Type: application/octet-stream; name=\"$filename\"");
2074         }
2075     }
2076
2077     //send the content-length header if the calling function provides it
2078     if ($filesize > 0) {
2079         header("Content-Length: $filesize");
2080     }
2081
2082 }  // end fn SendDownloadHeaders
2083
2084 ?>