functions/mime.php

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