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  * $Id$
  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, $encoding) {
 161
 162     /* Don't kill the connection if the browser is over a dialup
 163      * and it would take over 30 seconds to download it.
 164      * Dont call set_time_limit in safe mode.
 165      */
 166
 167     if (!ini_get('safe_mode')) {
 168         set_time_limit(0);
 169     }
 170     /* in case of base64 encoded attachments, do not buffer them.
 171        Instead, echo the decoded attachment directly to screen */
 172     if (strtolower($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, $username, $key, $imapServerAddress, $imapPort,
 345            $show_html_default, $sort, $has_unsafe_images, $passed_ent_id;
 346     global $languages, $squirrelmail_language;
 347
 348     if( !sqgetGlobalVar('view_unsafe_images', $view_unsafe_images, SQ_GET) ) {
 349         $view_unsafe_images = false;
 350     }
 351
 352     $body = '';
 353     $urlmailbox = urlencode($mailbox);
 354     $body_message = getEntity($message, $ent_num);
 355     if (($body_message->header->type0 == 'text') ||
 356         ($body_message->header->type0 == 'rfc822')) {
 357         $body = mime_fetch_body ($imap_stream, $id, $ent_num);
 358         $body = decodeBody($body, $body_message->header->encoding);
 359
 360         if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 361             function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
 362             if (mb_detect_encoding($body) != 'ASCII') {
 363                 $body = $languages[$squirrelmail_language]['XTRA_CODE']('decode', $body);
 364             }
 365         }
 366         $hookResults = do_hook("message_body", $body);
 367         $body = $hookResults[1];
 368
 369         /* If there are other types that shouldn't be formatted, add
 370          * them here.
 371          */
 372
 373         if ($body_message->header->type1 == 'html') {
 374             if ($show_html_default <> 1) {
 375                 $entity_conv = array('&nbsp;' => ' ',
 376                                      '<p>'    => "\n",
 377                                      '<br>'   => "\n",
 378                                      '<P>'    => "\n",
 379                                      '<BR>'   => "\n",
 380                                      '&gt;'   => '>',
 381                                      '&lt;'   => '<');
 382                 $body = strtr($body, $entity_conv);
 383                 $body = strip_tags($body);
 384                 $body = trim($body);
 385                 translateText($body, $wrap_at,
 386                               $body_message->header->getParameter('charset'));
 387             } else {
 388                 $body = magicHTML($body, $id, $message, $mailbox);
 389             }
 390         } else {
 391             translateText($body, $wrap_at,
 392                           $body_message->header->getParameter('charset'));
 393         }
 394         $link = 'passed_id=' . $id . '&amp;ent_id='.$ent_num.
 395                 '&amp;mailbox=' . $urlmailbox .'&amp;sort=' . $sort .
 396                 '&amp;startMessage=' . $startMessage . '&amp;show_more=0';
 397         if (isset($passed_ent_id)) {
 398             $link .= '&amp;passed_ent_id='.$passed_ent_id;
 399         }
 400         $body .= '<center><small><a href="download.php?absolute_dl=true&amp;' .
 401                  $link . '">' . _("Download this as a file") .  '</a>';
 402         if ($view_unsafe_images) {
 403             $text = _("Hide Unsafe Images");
 404         } else {
 405             if (isset($has_unsafe_images) && $has_unsafe_images) {
 406                 $link .= '&amp;view_unsafe_images=1';
 407                 $text = _("View Unsafe Images");
 408             } else {
 409                 $text = '';
 410             }
 411         }
 412         if($text != '') {
 413             $body .= '&nbsp;|&nbsp;<a href="read_body.php?' . $link . '">' . $text . '</a>';
 414         }
 415         $body .= '</small></center><br>' . "\n";
 416     }
 417     return $body;
 418 }
 419
 420
 421 function formatAttachments($message, $exclude_id, $mailbox, $id) {
 422     global $where, $what, $startMessage, $color;
 423     static $ShownHTML = 0;
 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         /* This executes the attachment hook with a specific MIME-type.
 508          * If that doesn't have results, it tries if there's a rule
 509          * for a more generic type.
 510          */
 511         $hookresults = do_hook("attachment $type0/$type1", $links,
 512                                $startMessage, $id, $urlMailbox, $ent, $defaultlink,
 513                                $display_filename, $where, $what);
 514         if(count($hookresults[1]) <= 1) {
 515             $hookresults = do_hook("attachment $type0/*", $links,
 516                                    $startMessage, $id, $urlMailbox, $ent, $defaultlink,
 517                                    $display_filename, $where, $what);
 518         }
 519
 520         $links = $hookresults[1];
 521         $defaultlink = $hookresults[6];
 522
 523         $attachments .= '<TR><TD>' .
 524                         '<A HREF="'.$defaultlink.'">'.decodeHeader($display_filename).'</A>&nbsp;</TD>' .
 525                         '<TD><SMALL><b>' . show_readable_size($header->size) .
 526                         '</b>&nbsp;&nbsp;</small></TD>' .
 527                         "<TD><SMALL>[ $type0/$type1 ]&nbsp;</SMALL></TD>" .
 528                         '<TD><SMALL>';
 529         $attachments .= '<b>' . $description . '</b>';
 530         $attachments .= '</SMALL></TD><TD><SMALL>&nbsp;';
 531
 532         $skipspaces = 1;
 533         foreach ($links as $val) {
 534             if ($skipspaces) {
 535                 $skipspaces = 0;
 536             } else {
 537                 $attachments .= '&nbsp;&nbsp;|&nbsp;&nbsp;';
 538             }
 539             $attachments .= '<a href="' . $val['href'] . '">' .  $val['text'] . '</a>';
 540         }
 541         unset($links);
 542         $attachments .= "</TD></TR>\n";
 543     }
 544     $attachmentadd = do_hook_function('attachments_bottom',$attachments);
 545     if ($attachmentadd != '')
 546         $attachments = $attachmentadd;
 547     return $attachments;
 548 }
 549
 550 function sqimap_base64_decode(&$string) {
 551     $string = str_replace("\r\n", "\n", $string);
 552     $string = base64_decode($string);
 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, $squirrelmail_language;
 601     if (is_array($string)) {
 602         $string = implode("\n", $string);
 603     }
 604
 605     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 606         function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
 607         $string = $languages[$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             $ret .= $res[1];
 640             $encoding = ucfirst($res[3]);
 641             switch ($encoding)
 642             {
 643             case 'B':
 644                 $replace = base64_decode($res[4]);
 645                 $ret .= charset_decode($res[2],$replace);
 646                 break;
 647             case 'Q':
 648                 $replace = str_replace('_', ' ', $res[4]);
 649                 $replace = preg_replace('/=([0-9a-f]{2})/ie', 'chr(hexdec("\1"))',
 650                                     $replace);
 651         /* decide about valid decoding */
 652         if ($decide && is_conversion_safe($res[2])) {
 653           $utfencode=true;
 654           $can_be_decoded=true;
 655         } else {
 656           $can_be_decoded=false;
 657         }
 658                 /* Only encode into entities by default. Some places
 659                  * don't need the encoding, like the compose form.
 660                  */
 661                 if ($utfencode) {
 662                     $replace = charset_decode($res[2], $replace);
 663                 } else {
 664                     if ($htmlsave) {
 665                         $replace = htmlspecialchars($replace);
 666                     }
 667                 }
 668                 $ret .= $replace;
 669                 break;
 670             default:
 671                 break;
 672             }
 673             $chunk = $res[5];
 674             $encoded = true;
 675         }
 676         if (!$encoded) {
 677             if ($htmlsave) {
 678                 $ret .= '&#32;';
 679             } else {
 680                 $ret .= ' ';
 681             }
 682         }
 683
 684         if (!$encoded && $htmlsave) {
 685             $ret .= htmlspecialchars($chunk);
 686         } else {
 687             $ret .= $chunk;
 688         }
 689         ++$i;
 690     }
 691     /* remove the first added space */
 692     if ($ret) {
 693         if ($htmlsave) {
 694             $ret = substr($ret,5);
 695         } else {
 696             $ret = substr($ret,1);
 697         }
 698     }
 699
 700     return $ret;
 701 }
 702
 703 /**
 704  * Encodes header as quoted-printable
 705  *
 706  * Encode a string according to RFC 1522 for use in headers if it
 707  * contains 8-bit characters or anything that looks like it should
 708  * be encoded.
 709  *
 710  * @param string $string header string, that has to be encoded
 711  * @return string quoted-printable encoded string
 712  */
 713 function encodeHeader ($string) {
 714     global $default_charset, $languages, $squirrelmail_language;
 715
 716     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 717         function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
 718         return  $languages[$squirrelmail_language]['XTRA_CODE']('encodeheader', $string);
 719     }
 720     // instead of removing nbsp here, we don't add it in decodeHeader
 721     //    if (strtolower($default_charset) == 'iso-8859-1') {
 722     //    $string = str_replace("\240",' ',$string);
 723     //}
 724
 725     // Encode only if the string contains 8-bit characters or =?
 726     $j = strlen($string);
 727     $max_l = 75 - strlen($default_charset) - 7;
 728     $aRet = array();
 729     $ret = '';
 730     $iEncStart = $enc_init = false;
 731     $cur_l = $iOffset = 0;
 732     for($i = 0; $i < $j; ++$i) {
 733         switch($string{$i})
 734         {
 735         case '=':
 736         case '<':
 737         case '>':
 738         case ',':
 739         case '?':
 740         case '_':
 741             if ($iEncStart === false) {
 742                 $iEncStart = $i;
 743             }
 744             $cur_l+=3;
 745             if ($cur_l > ($max_l-2)) {
 746                 /* if there is an stringpart that doesn't need encoding, add it */
 747                 $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 748                 $aRet[] = "=?$default_charset?Q?$ret?=";
 749                 $iOffset = $i;
 750                 $cur_l = 0;
 751                 $ret = '';
 752                 $iEncStart = false;
 753             } else {
 754                 $ret .= sprintf("=%02X",ord($string{$i}));
 755             }
 756             break;
 757         case '(':
 758         case ')':
 759             if ($iEncStart !== false) {
 760                 $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 761                 $aRet[] = "=?$default_charset?Q?$ret?=";
 762                 $iOffset = $i;
 763                 $cur_l = 0;
 764                 $ret = '';
 765                 $iEncStart = false;
 766             }
 767             break;
 768         case ' ':
 769             if ($iEncStart !== false) {
 770                 $cur_l++;
 771                 if ($cur_l > $max_l) {
 772                     $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 773                     $aRet[] = "=?$default_charset?Q?$ret?=";
 774                     $iOffset = $i;
 775                     $cur_l = 0;
 776                     $ret = '';
 777                     $iEncStart = false;
 778                 } else {
 779                     $ret .= '_';
 780                 }
 781             }
 782             break;
 783         default:
 784             $k = ord($string{$i});
 785             if ($k > 126) {
 786                 if ($iEncStart === false) {
 787                     // do not start encoding in the middle of a string, also take the rest of the word.
 788                     $sLeadString = substr($string,0,$i);
 789                     $aLeadString = explode(' ',$sLeadString);
 790                     $sToBeEncoded = array_pop($aLeadString);
 791                     $iEncStart = $i - strlen($sToBeEncoded);
 792                     $ret .= $sToBeEncoded;
 793                     $cur_l += strlen($sToBeEncoded);
 794                 }
 795                 $cur_l += 3;
 796                 /* first we add the encoded string that reached it's max size */
 797                 if ($cur_l > ($max_l-2)) {
 798                     $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 799                     $aRet[] = "=?$default_charset?Q?$ret?= "; /* the next part is also encoded => separate by space */
 800                     $cur_l = 3;
 801                     $ret = '';
 802                     $iOffset = $i;
 803                     $iEncStart = $i;
 804                 }
 805                 $enc_init = true;
 806                 $ret .= sprintf("=%02X", $k);
 807             } else {
 808                 if ($iEncStart !== false) {
 809                     $cur_l++;
 810                     if ($cur_l > $max_l) {
 811                         $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 812                         $aRet[] = "=?$default_charset?Q?$ret?=";
 813                         $iEncStart = false;
 814                         $iOffset = $i;
 815                         $cur_l = 0;
 816                         $ret = '';
 817                     } else {
 818                         $ret .= $string{$i};
 819                     }
 820                 }
 821             }
 822             break;
 823         }
 824     }
 825
 826     if ($enc_init) {
 827         if ($iEncStart !== false) {
 828             $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 829             $aRet[] = "=?$default_charset?Q?$ret?=";
 830         } else {
 831             $aRet[] = substr($string,$iOffset);
 832         }
 833         $string = implode('',$aRet);
 834     }
 835     return $string;
 836 }
 837
 838 /* This function trys to locate the entity_id of a specific mime element */
 839 function find_ent_id($id, $message) {
 840     for ($i = 0, $ret = ''; $ret == '' && $i < count($message->entities); $i++) {
 841         if ($message->entities[$i]->header->type0 == 'multipart')  {
 842             $ret = find_ent_id($id, $message->entities[$i]);
 843         } else {
 844             if (strcasecmp($message->entities[$i]->header->id, $id) == 0) {
 845 //                if (sq_check_save_extension($message->entities[$i])) {
 846                     return $message->entities[$i]->entity_id;
 847 //                }
 848             }
 849         }
 850     }
 851     return $ret;
 852 }
 853
 854 function sq_check_save_extension($message) {
 855     $filename = $message->getFilename();
 856     $ext = substr($filename, strrpos($filename,'.')+1);
 857     $save_extensions = array('jpg','jpeg','gif','png','bmp');
 858     return in_array($ext, $save_extensions);
 859 }
 860
 861
 862 /**
 863  ** HTMLFILTER ROUTINES
 864  */
 865
 866 /**
 867  * This function is more or less a wrapper around stripslashes. Apparently
 868  * Explorer is stupid enough to just remove the backslashes and then
 869  * execute the content of the attribute as if nothing happened.
 870  * Who does that?
 871  *
 872  * @param  attvalue   The value of the attribute
 873  * @return attvalue   The value of the attribute stripslashed.
 874  */
 875 function sq_unbackslash($attvalue){
 876     /**
 877      * Remove any backslashes. See if there are any first.
 878      */
 879
 880     if (strstr($attvalue, '\\') !== false){
 881         $attvalue = stripslashes($attvalue);
 882     }
 883     return $attvalue;
 884 }
 885
 886 /**
 887  * Kill any tabs, newlines, or carriage returns. Our friends the
 888  * makers of the browser with 95% market value decided that it'd
 889  * be funny to make "java[tab]script" be just as good as "javascript".
 890  *
 891  * @param  attvalue  The attribute value before extraneous spaces removed.
 892  * @return attvalue  The attribute value after extraneous spaces removed.
 893  */
 894 function sq_unspace($attvalue){
 895     if (strcspn($attvalue, "\t\r\n") != strlen($attvalue)){
 896         $attvalue = str_replace(Array("\t", "\r", "\n"), Array('', '', ''),
 897                                 $attvalue);
 898     }
 899     return $attvalue;
 900 }
 901
 902 /**
 903  * This function returns the final tag out of the tag name, an array
 904  * of attributes, and the type of the tag. This function is called by
 905  * sq_sanitize internally.
 906  *
 907  * @param  $tagname  the name of the tag.
 908  * @param  $attary   the array of attributes and their values
 909  * @param  $tagtype  The type of the tag (see in comments).
 910  * @return           a string with the final tag representation.
 911  */
 912 function sq_tagprint($tagname, $attary, $tagtype){
 913     $me = 'sq_tagprint';
 914
 915     if ($tagtype == 2){
 916         $fulltag = '</' . $tagname . '>';
 917     } else {
 918         $fulltag = '<' . $tagname;
 919         if (is_array($attary) && sizeof($attary)){
 920             $atts = Array();
 921             while (list($attname, $attvalue) = each($attary)){
 922                 array_push($atts, "$attname=$attvalue");
 923             }
 924             $fulltag .= ' ' . join(" ", $atts);
 925         }
 926         if ($tagtype == 3){
 927             $fulltag .= ' /';
 928         }
 929         $fulltag .= '>';
 930     }
 931     return $fulltag;
 932 }
 933
 934 /**
 935  * A small helper function to use with array_walk. Modifies a by-ref
 936  * value and makes it lowercase.
 937  *
 938  * @param  $val a value passed by-ref.
 939  * @return      void since it modifies a by-ref value.
 940  */
 941 function sq_casenormalize(&$val){
 942     $val = strtolower($val);
 943 }
 944
 945 /**
 946  * This function skips any whitespace from the current position within
 947  * a string and to the next non-whitespace value.
 948  *
 949  * @param  $body   the string
 950  * @param  $offset the offset within the string where we should start
 951  *                 looking for the next non-whitespace character.
 952  * @return         the location within the $body where the next
 953  *                 non-whitespace char is located.
 954  */
 955 function sq_skipspace($body, $offset){
 956     $me = 'sq_skipspace';
 957     preg_match('/^(\s*)/s', substr($body, $offset), $matches);
 958     if (sizeof($matches{1})){
 959         $count = strlen($matches{1});
 960         $offset += $count;
 961     }
 962     return $offset;
 963 }
 964
 965 /**
 966  * This function looks for the next character within a string.  It's
 967  * really just a glorified "strpos", except it catches if failures
 968  * nicely.
 969  *
 970  * @param  $body   The string to look for needle in.
 971  * @param  $offset Start looking from this position.
 972  * @param  $needle The character/string to look for.
 973  * @return         location of the next occurance of the needle, or
 974  *                 strlen($body) if needle wasn't found.
 975  */
 976 function sq_findnxstr($body, $offset, $needle){
 977     $me  = 'sq_findnxstr';
 978     $pos = strpos($body, $needle, $offset);
 979     if ($pos === FALSE){
 980         $pos = strlen($body);
 981     }
 982     return $pos;
 983 }
 984
 985 /**
 986  * This function takes a PCRE-style regexp and tries to match it
 987  * within the string.
 988  *
 989  * @param  $body   The string to look for needle in.
 990  * @param  $offset Start looking from here.
 991  * @param  $reg    A PCRE-style regex to match.
 992  * @return         Returns a false if no matches found, or an array
 993  *                 with the following members:
 994  *                 - integer with the location of the match within $body
 995  *                 - string with whatever content between offset and the match
 996  *                 - string with whatever it is we matched
 997  */
 998 function sq_findnxreg($body, $offset, $reg){
 999     $me = 'sq_findnxreg';
1000     $matches = Array();
1001     $retarr = Array();
1002     preg_match("%^(.*?)($reg)%si", substr($body, $offset), $matches);
1003     if (!isset($matches{0}) || !$matches{0}){
1004         $retarr = false;
1005     } else {
1006         $retarr{0} = $offset + strlen($matches{1});
1007         $retarr{1} = $matches{1};
1008         $retarr{2} = $matches{2};
1009     }
1010     return $retarr;
1011 }
1012
1013 /**
1014  * This function looks for the next tag.
1015  *
1016  * @param  $body   String where to look for the next tag.
1017  * @param  $offset Start looking from here.
1018  * @return         false if no more tags exist in the body, or
1019  *                 an array with the following members:
1020  *                 - string with the name of the tag
1021  *                 - array with attributes and their values
1022  *                 - integer with tag type (1, 2, or 3)
1023  *                 - integer where the tag starts (starting "<")
1024  *                 - integer where the tag ends (ending ">")
1025  *                 first three members will be false, if the tag is invalid.
1026  */
1027 function sq_getnxtag($body, $offset){
1028     $me = 'sq_getnxtag';
1029     if ($offset > strlen($body)){
1030         return false;
1031     }
1032     $lt = sq_findnxstr($body, $offset, "<");
1033     if ($lt == strlen($body)){
1034         return false;
1035     }
1036     /**
1037      * We are here:
1038      * blah blah <tag attribute="value">
1039      * \---------^
1040      */
1041     $pos = sq_skipspace($body, $lt+1);
1042     if ($pos >= strlen($body)){
1043         return Array(false, false, false, $lt, strlen($body));
1044     }
1045     /**
1046      * There are 3 kinds of tags:
1047      * 1. Opening tag, e.g.:
1048      *    <a href="blah">
1049      * 2. Closing tag, e.g.:
1050      *    </a>
1051      * 3. XHTML-style content-less tag, e.g.:
1052      *    <img src="blah"/>
1053      */
1054     $tagtype = false;
1055     switch (substr($body, $pos, 1)){
1056         case '/':
1057             $tagtype = 2;
1058             $pos++;
1059             break;
1060         case '!':
1061             /**
1062              * A comment or an SGML declaration.
1063              */
1064             if (substr($body, $pos+1, 2) == "--"){
1065                 $gt = strpos($body, "-->", $pos);
1066                 if ($gt === false){
1067                     $gt = strlen($body);
1068                 } else {
1069                     $gt += 2;
1070                 }
1071                 return Array(false, false, false, $lt, $gt);
1072             } else {
1073                 $gt = sq_findnxstr($body, $pos, ">");
1074                 return Array(false, false, false, $lt, $gt);
1075             }
1076             break;
1077         default:
1078             /**
1079              * Assume tagtype 1 for now. If it's type 3, we'll switch values
1080              * later.
1081              */
1082             $tagtype = 1;
1083             break;
1084     }
1085
1086     $tag_start = $pos;
1087     $tagname = '';
1088     /**
1089      * Look for next [\W-_], which will indicate the end of the tag name.
1090      */
1091     $regary = sq_findnxreg($body, $pos, "[^\w\-_]");
1092     if ($regary == false){
1093         return Array(false, false, false, $lt, strlen($body));
1094     }
1095     list($pos, $tagname, $match) = $regary;
1096     $tagname = strtolower($tagname);
1097
1098     /**
1099      * $match can be either of these:
1100      * '>'  indicating the end of the tag entirely.
1101      * '\s' indicating the end of the tag name.
1102      * '/'  indicating that this is type-3 xhtml tag.
1103      *
1104      * Whatever else we find there indicates an invalid tag.
1105      */
1106     switch ($match){
1107         case '/':
1108             /**
1109              * This is an xhtml-style tag with a closing / at the
1110              * end, like so: <img src="blah"/>. Check if it's followed
1111              * by the closing bracket. If not, then this tag is invalid
1112              */
1113             if (substr($body, $pos, 2) == "/>"){
1114                 $pos++;
1115                 $tagtype = 3;
1116             } else {
1117                 $gt = sq_findnxstr($body, $pos, ">");
1118                 $retary = Array(false, false, false, $lt, $gt);
1119                 return $retary;
1120             }
1121         case '>':
1122             return Array($tagname, false, $tagtype, $lt, $pos);
1123             break;
1124         default:
1125             /**
1126              * Check if it's whitespace
1127              */
1128             if (!preg_match('/\s/', $match)){
1129                 /**
1130                  * This is an invalid tag! Look for the next closing ">".
1131                  */
1132                 $gt = sq_findnxstr($body, $lt, ">");
1133                 return Array(false, false, false, $lt, $gt);
1134             }
1135             break;
1136     }
1137
1138     /**
1139      * At this point we're here:
1140      * <tagname  attribute='blah'>
1141      * \-------^
1142      *
1143      * At this point we loop in order to find all attributes.
1144      */
1145     $attname = '';
1146     $atttype = false;
1147     $attary = Array();
1148
1149     while ($pos <= strlen($body)){
1150         $pos = sq_skipspace($body, $pos);
1151         if ($pos == strlen($body)){
1152             /**
1153              * Non-closed tag.
1154              */
1155             return Array(false, false, false, $lt, $pos);
1156         }
1157         /**
1158          * See if we arrived at a ">" or "/>", which means that we reached
1159          * the end of the tag.
1160          */
1161         $matches = Array();
1162         if (preg_match("%^(\s*)(>|/>)%s", substr($body, $pos), $matches)) {
1163             /**
1164              * Yep. So we did.
1165              */
1166             $pos += strlen($matches{1});
1167             if ($matches{2} == "/>"){
1168                 $tagtype = 3;
1169                 $pos++;
1170             }
1171             return Array($tagname, $attary, $tagtype, $lt, $pos);
1172         }
1173
1174         /**
1175          * There are several types of attributes, with optional
1176          * [:space:] between members.
1177          * Type 1:
1178          *   attrname[:space:]=[:space:]'CDATA'
1179          * Type 2:
1180          *   attrname[:space:]=[:space:]"CDATA"
1181          * Type 3:
1182          *   attr[:space:]=[:space:]CDATA
1183          * Type 4:
1184          *   attrname
1185          *
1186          * We leave types 1 and 2 the same, type 3 we check for
1187          * '"' and convert to "&quot" if needed, then wrap in
1188          * double quotes. Type 4 we convert into:
1189          * attrname="yes".
1190          */
1191         $regary = sq_findnxreg($body, $pos, "[^:\w\-_]");
1192         if ($regary == false){
1193             /**
1194              * Looks like body ended before the end of tag.
1195              */
1196             return Array(false, false, false, $lt, strlen($body));
1197         }
1198         list($pos, $attname, $match) = $regary;
1199         $attname = strtolower($attname);
1200         /**
1201          * We arrived at the end of attribute name. Several things possible
1202          * here:
1203          * '>'  means the end of the tag and this is attribute type 4
1204          * '/'  if followed by '>' means the same thing as above
1205          * '\s' means a lot of things -- look what it's followed by.
1206          *      anything else means the attribute is invalid.
1207          */
1208         switch($match){
1209             case '/':
1210                 /**
1211                  * This is an xhtml-style tag with a closing / at the
1212                  * end, like so: <img src="blah"/>. Check if it's followed
1213                  * by the closing bracket. If not, then this tag is invalid
1214                  */
1215                 if (substr($body, $pos, 2) == "/>"){
1216                     $pos++;
1217                     $tagtype = 3;
1218                 } else {
1219                     $gt = sq_findnxstr($body, $pos, ">");
1220                     $retary = Array(false, false, false, $lt, $gt);
1221                     return $retary;
1222                 }
1223             case '>':
1224                 $attary{$attname} = '"yes"';
1225                 return Array($tagname, $attary, $tagtype, $lt, $pos);
1226                 break;
1227             default:
1228                 /**
1229                  * Skip whitespace and see what we arrive at.
1230                  */
1231                 $pos = sq_skipspace($body, $pos);
1232                 $char = substr($body, $pos, 1);
1233                 /**
1234                  * Two things are valid here:
1235                  * '=' means this is attribute type 1 2 or 3.
1236                  * \w means this was attribute type 4.
1237                  * anything else we ignore and re-loop. End of tag and
1238                  * invalid stuff will be caught by our checks at the beginning
1239                  * of the loop.
1240                  */
1241                 if ($char == "="){
1242                     $pos++;
1243                     $pos = sq_skipspace($body, $pos);
1244                     /**
1245                      * Here are 3 possibilities:
1246                      * "'"  attribute type 1
1247                      * '"'  attribute type 2
1248                      * everything else is the content of tag type 3
1249                      */
1250                     $quot = substr($body, $pos, 1);
1251                     if ($quot == "'"){
1252                         $regary = sq_findnxreg($body, $pos+1, "\'");
1253                         if ($regary == false){
1254                             return Array(false, false, false, $lt, strlen($body));
1255                         }
1256                         list($pos, $attval, $match) = $regary;
1257                         $pos++;
1258                         $attary{$attname} = "'" . $attval . "'";
1259                     } else if ($quot == '"'){
1260                         $regary = sq_findnxreg($body, $pos+1, '\"');
1261                         if ($regary == false){
1262                             return Array(false, false, false, $lt, strlen($body));
1263                         }
1264                         list($pos, $attval, $match) = $regary;
1265                         $pos++;
1266                         $attary{$attname} = '"' . $attval . '"';
1267                     } else {
1268                         /**
1269                          * These are hateful. Look for \s, or >.
1270                          */
1271                         $regary = sq_findnxreg($body, $pos, "[\s>]");
1272                         if ($regary == false){
1273                             return Array(false, false, false, $lt, strlen($body));
1274                         }
1275                         list($pos, $attval, $match) = $regary;
1276                         /**
1277                          * If it's ">" it will be caught at the top.
1278                          */
1279                         $attval = preg_replace("/\"/s", "&quot;", $attval);
1280                         $attary{$attname} = '"' . $attval . '"';
1281                     }
1282                 } else if (preg_match("|[\w/>]|", $char)) {
1283                     /**
1284                      * That was attribute type 4.
1285                      */
1286                     $attary{$attname} = '"yes"';
1287                 } else {
1288                     /**
1289                      * An illegal character. Find next '>' and return.
1290                      */
1291                     $gt = sq_findnxstr($body, $pos, ">");
1292                     return Array(false, false, false, $lt, $gt);
1293                 }
1294                 break;
1295         }
1296     }
1297     /**
1298      * The fact that we got here indicates that the tag end was never
1299      * found. Return invalid tag indication so it gets stripped.
1300      */
1301     return Array(false, false, false, $lt, strlen($body));
1302 }
1303
1304 /**
1305  * This function checks attribute values for entity-encoded values
1306  * and returns them translated into 8-bit strings so we can run
1307  * checks on them.
1308  *
1309  * @param  $attvalue A string to run entity check against.
1310  * @return           Translated value.
1311  */
1312
1313 function sq_deent($attvalue){
1314     $me = 'sq_deent';
1315     /**
1316      * See if we have to run the checks first. All entities must start
1317      * with "&".
1318      */
1319     if (strpos($attvalue, '&') === false){
1320         return $attvalue;
1321     }
1322     /**
1323      * Check named entities first.
1324      */
1325     $trans = get_html_translation_table(HTML_ENTITIES);
1326     /**
1327      * Leave &quot; in, as it can mess us up.
1328      */
1329     $trans = array_flip($trans);
1330     unset($trans{'&quot;'});
1331     while (list($ent, $val) = each($trans)){
1332         $attvalue = preg_replace('/' . $ent . '*/si', $val, $attvalue);
1333     }
1334     /**
1335      * Now translate numbered entities from 1 to 255 if needed.
1336      */
1337     if (strpos($attvalue, '#') !== false){
1338         $omit = Array(34, 39);
1339         for ($asc = 256; $asc >= 0; $asc--){
1340             if (!in_array($asc, $omit)){
1341                 $chr = chr($asc);
1342                 $octrule = '/\&#0*' . $asc . ';*/si';
1343                 $hexrule = '/\&#x0*' . dechex($asc) . ';*/si';
1344                 $attvalue = preg_replace($octrule, $chr, $attvalue);
1345                 $attvalue = preg_replace($hexrule, $chr, $attvalue);
1346             }
1347         }
1348     }
1349     return $attvalue;
1350 }
1351
1352 /**
1353  * This function runs various checks against the attributes.
1354  *
1355  * @param  $tagname         String with the name of the tag.
1356  * @param  $attary          Array with all tag attributes.
1357  * @param  $rm_attnames     See description for sq_sanitize
1358  * @param  $bad_attvals     See description for sq_sanitize
1359  * @param  $add_attr_to_tag See description for sq_sanitize
1360  * @param  $message         message object
1361  * @param  $id              message id
1362  * @return                  Array with modified attributes.
1363  */
1364 function sq_fixatts($tagname,
1365                     $attary,
1366                     $rm_attnames,
1367                     $bad_attvals,
1368                     $add_attr_to_tag,
1369                     $message,
1370                     $id,
1371                     $mailbox
1372                     ){
1373     $me = 'sq_fixatts';
1374     while (list($attname, $attvalue) = each($attary)){
1375         /**
1376          * See if this attribute should be removed.
1377          */
1378         foreach ($rm_attnames as $matchtag=>$matchattrs){
1379             if (preg_match($matchtag, $tagname)){
1380                 foreach ($matchattrs as $matchattr){
1381                     if (preg_match($matchattr, $attname)){
1382                         unset($attary{$attname});
1383                         continue;
1384                     }
1385                 }
1386             }
1387         }
1388         /**
1389          * Remove any backslashes, entities, and extraneous whitespace.
1390          */
1391         $attvalue = sq_unbackslash($attvalue);
1392         $attvalue = sq_deent($attvalue);
1393         $attvalue = sq_unspace($attvalue);
1394
1395         /**
1396          * Remove \r \n \t \0 " " "\\"
1397          */
1398         $attvalue = str_replace(Array("\r", "\n", "\t", "\0", " ", "\\"),
1399                         Array('', '','','','',''), $attvalue);
1400
1401         /**
1402          * Now let's run checks on the attvalues.
1403          * I don't expect anyone to comprehend this. If you do,
1404          * get in touch with me so I can drive to where you live and
1405          * shake your hand personally. :)
1406          */
1407         foreach ($bad_attvals as $matchtag=>$matchattrs){
1408             if (preg_match($matchtag, $tagname)){
1409                 foreach ($matchattrs as $matchattr=>$valary){
1410                     if (preg_match($matchattr, $attname)){
1411                         /**
1412                          * There are two arrays in valary.
1413                          * First is matches.
1414                          * Second one is replacements
1415                          */
1416                         list($valmatch, $valrepl) = $valary;
1417                         $newvalue =
1418                             preg_replace($valmatch, $valrepl, $attvalue);
1419                         if ($newvalue != $attvalue){
1420                             $attary{$attname} = $newvalue;
1421                         }
1422                     }
1423                 }
1424             }
1425         }
1426         /**
1427          * Turn cid: urls into http-friendly ones.
1428          */
1429         if (preg_match("/^[\'\"]\s*cid:/si", $attvalue)){
1430             $attary{$attname} = sq_cid2http($message, $id, $attvalue, $mailbox);
1431         }
1432     }
1433     /**
1434      * See if we need to append any attributes to this tag.
1435      */
1436     foreach ($add_attr_to_tag as $matchtag=>$addattary){
1437         if (preg_match($matchtag, $tagname)){
1438             $attary = array_merge($attary, $addattary);
1439         }
1440     }
1441     return $attary;
1442 }
1443
1444 /**
1445  * This function edits the style definition to make them friendly and
1446  * usable in squirrelmail.
1447  *
1448  * @param  $message  the message object
1449  * @param  $id       the message id
1450  * @param  $content  a string with whatever is between <style> and </style>
1451  * @param  $mailbox  the message mailbox
1452  * @return           a string with edited content.
1453  */
1454 function sq_fixstyle($body, $pos, $message, $id, $mailbox){
1455     global $view_unsafe_images;
1456     $me = 'sq_fixstyle';
1457     $ret = sq_findnxreg($body, $pos, '</\s*style\s*>');
1458     if ($ret == FALSE){
1459         return array(FALSE, strlen($body));
1460     }
1461     $newpos = $ret[0] + strlen($ret[2]);
1462     $content = $ret[1];
1463     /**
1464      * First look for general BODY style declaration, which would be
1465      * like so:
1466      * body {background: blah-blah}
1467      * and change it to .bodyclass so we can just assign it to a <div>
1468      */
1469     $content = preg_replace("|body(\s*\{.*?\})|si", ".bodyclass\\1", $content);
1470     $secremoveimg = '../images/' . _("sec_remove_eng.png");
1471     /**
1472      * Fix url('blah') declarations.
1473      */
1474     $content = preg_replace("|url\s*\(\s*([\'\"])\s*\S+script\s*:.*?([\'\"])\s*\)|si",
1475                             "url(\\1$secremoveimg\\2)", $content);
1476     /**
1477      * Fix url('https*://.*) declarations but only if $view_unsafe_images
1478      * is false.
1479      */
1480     if (!$view_unsafe_images){
1481         $content = preg_replace("|url\s*\(\s*([\'\"])\s*https*:.*?([\'\"])\s*\)|si",
1482                                 "url(\\1$secremoveimg\\2)", $content);
1483     }
1484
1485     /**
1486      * Fix urls that refer to cid:
1487      */
1488     while (preg_match("|url\s*\(\s*([\'\"]\s*cid:.*?[\'\"])\s*\)|si",
1489                       $content, $matches)){
1490         $cidurl = $matches{1};
1491         $httpurl = sq_cid2http($message, $id, $cidurl, $mailbox);
1492         $content = preg_replace("|url\s*\(\s*$cidurl\s*\)|si",
1493                                 "url($httpurl)", $content);
1494     }
1495
1496     /**
1497      * Fix stupid css declarations which lead to vulnerabilities
1498      * in IE.
1499      */
1500     $match   = Array('/expression/i',
1501                      '/behaviou*r/i',
1502                      '/binding/i',
1503                      '/include-source/i');
1504     $replace = Array('idiocy', 'idiocy', 'idiocy', 'idiocy');
1505     $content = preg_replace($match, $replace, $content);
1506     return array($content, $newpos);
1507 }
1508
1509 /**
1510  * This function converts cid: url's into the ones that can be viewed in
1511  * the browser.
1512  *
1513  * @param  $message  the message object
1514  * @param  $id       the message id
1515  * @param  $cidurl   the cid: url.
1516  * @param  $mailbox  the message mailbox
1517  * @return           a string with a http-friendly url
1518  */
1519 function sq_cid2http($message, $id, $cidurl, $mailbox){
1520     /**
1521      * Get rid of quotes.
1522      */
1523     $quotchar = substr($cidurl, 0, 1);
1524     if ($quotchar == '"' || $quotchar == "'"){
1525         $cidurl = str_replace($quotchar, "", $cidurl);
1526     } else {
1527         $quotchar = '';
1528     }
1529     $cidurl = substr(trim($cidurl), 4);
1530     $linkurl = find_ent_id($cidurl, $message);
1531     /* in case of non-save cid links $httpurl should be replaced by a sort of
1532        unsave link image */
1533     $httpurl = '';
1534     if ($linkurl) {
1535         $httpurl = $quotchar . SM_PATH . 'src/download.php?absolute_dl=true&amp;' .
1536                    "passed_id=$id&amp;mailbox=" . urlencode($mailbox) .
1537                    '&amp;ent_id=' . $linkurl . $quotchar;
1538     }
1539     return $httpurl;
1540 }
1541
1542 /**
1543  * This function changes the <body> tag into a <div> tag since we
1544  * can't really have a body-within-body.
1545  *
1546  * @param  $attary   an array of attributes and values of <body>
1547  * @param  $mailbox  mailbox we're currently reading (for cid2http)
1548  * @param  $message  current message (for cid2http)
1549  * @param  $id       current message id (for cid2http)
1550  * @return           a modified array of attributes to be set for <div>
1551  */
1552 function sq_body2div($attary, $mailbox, $message, $id){
1553     $me = 'sq_body2div';
1554     $divattary = Array('class' => "'bodyclass'");
1555     $bgcolor = '#ffffff';
1556     $text = '#000000';
1557     $has_bgc_stl = $has_txt_stl = false;
1558     $styledef = '';
1559     if (is_array($attary) && sizeof($attary) > 0){
1560         foreach ($attary as $attname=>$attvalue){
1561             $quotchar = substr($attvalue, 0, 1);
1562             $attvalue = str_replace($quotchar, "", $attvalue);
1563             switch ($attname){
1564                 case 'background':
1565                     $attvalue = sq_cid2http($message, $id,
1566                                             $attvalue, $mailbox);
1567                     $styledef .= "background-image: url('$attvalue'); ";
1568                     break;
1569                 case 'bgcolor':
1570                     $has_bgc_stl = true;
1571                     $styledef .= "background-color: $attvalue; ";
1572                     break;
1573                 case 'text':
1574                     $has_txt_stl = true;
1575                     $styledef .= "color: $attvalue; ";
1576                     break;
1577             }
1578         }
1579         // Outlook defines a white bgcolor and no text color. This can lead to
1580         // white text on a white bg with certain themes.
1581         if ($has_bgc_stl && !$has_txt_stl) {
1582             $styledef .= "color: $text; ";
1583         }
1584         if (strlen($styledef) > 0){
1585             $divattary{"style"} = "\"$styledef\"";
1586         }
1587     }
1588     return $divattary;
1589 }
1590
1591 /**
1592  * This is the main function and the one you should actually be calling.
1593  * There are several variables you should be aware of an which need
1594  * special description.
1595  *
1596  * Since the description is quite lengthy, see it here:
1597  * http://www.mricon.com/html/phpfilter.html
1598  *
1599  * @param $body                 the string with HTML you wish to filter
1600  * @param $tag_list             see description above
1601  * @param $rm_tags_with_content see description above
1602  * @param $self_closing_tags    see description above
1603  * @param $force_tag_closing    see description above
1604  * @param $rm_attnames          see description above
1605  * @param $bad_attvals          see description above
1606  * @param $add_attr_to_tag      see description above
1607  * @param $message              message object
1608  * @param $id                   message id
1609  * @return                      sanitized html safe to show on your pages.
1610  */
1611 function sq_sanitize($body,
1612                      $tag_list,
1613                      $rm_tags_with_content,
1614                      $self_closing_tags,
1615                      $force_tag_closing,
1616                      $rm_attnames,
1617                      $bad_attvals,
1618                      $add_attr_to_tag,
1619                      $message,
1620                      $id,
1621                      $mailbox
1622                      ){
1623     $me = 'sq_sanitize';
1624     $rm_tags = array_shift($tag_list);
1625     /**
1626      * Normalize rm_tags and rm_tags_with_content.
1627      */
1628     @array_walk($tag_list, 'sq_casenormalize');
1629     @array_walk($rm_tags_with_content, 'sq_casenormalize');
1630     @array_walk($self_closing_tags, 'sq_casenormalize');
1631     /**
1632      * See if tag_list is of tags to remove or tags to allow.
1633      * false  means remove these tags
1634      * true   means allow these tags
1635      */
1636     $curpos = 0;
1637     $open_tags = Array();
1638     $trusted = "\n<!-- begin sanitized html -->\n";
1639     $skip_content = false;
1640     /**
1641      * Take care of netscape's stupid javascript entities like
1642      * &{alert('boo')};
1643      */
1644     $body = preg_replace("/&(\{.*?\};)/si", "&amp;\\1", $body);
1645
1646     while (($curtag = sq_getnxtag($body, $curpos)) != FALSE){
1647         list($tagname, $attary, $tagtype, $lt, $gt) = $curtag;
1648         $free_content = substr($body, $curpos, $lt-$curpos);
1649         /**
1650          * Take care of <style>
1651          */
1652         if ($tagname == "style" && $tagtype == 1){
1653             list($free_content, $curpos) =
1654                 sq_fixstyle($body, $gt+1, $message, $id, $mailbox);
1655             if ($free_content != FALSE){
1656                 $trusted .= sq_tagprint($tagname, $attary, $tagtype);
1657                 $trusted .= $free_content;
1658                 $trusted .= sq_tagprint($tagname, false, 2);
1659             }
1660             continue;
1661         }
1662         if ($skip_content == false){
1663             $trusted .= $free_content;
1664         }
1665         if ($tagname != FALSE){
1666             if ($tagtype == 2){
1667                 if ($skip_content == $tagname){
1668                     /**
1669                      * Got to the end of tag we needed to remove.
1670                      */
1671                     $tagname = false;
1672                     $skip_content = false;
1673                 } else {
1674                     if ($skip_content == false){
1675                         if ($tagname == "body"){
1676                             $tagname = "div";
1677                         }
1678                         if (isset($open_tags{$tagname}) &&
1679                             $open_tags{$tagname} > 0){
1680                             $open_tags{$tagname}--;
1681                         } else {
1682                             $tagname = false;
1683                         }
1684                     }
1685                 }
1686             } else {
1687                 /**
1688                  * $rm_tags_with_content
1689                  */
1690                 if ($skip_content == false){
1691                     /**
1692                      * See if this is a self-closing type and change
1693                      * tagtype appropriately.
1694                      */
1695                     if ($tagtype == 1
1696                         && in_array($tagname, $self_closing_tags)){
1697                         $tagtype = 3;
1698                     }
1699                     /**
1700                      * See if we should skip this tag and any content
1701                      * inside it.
1702                      */
1703                     if ($tagtype == 1 &&
1704                         in_array($tagname, $rm_tags_with_content)){
1705                         $skip_content = $tagname;
1706                     } else {
1707                         if (($rm_tags == false
1708                              && in_array($tagname, $tag_list)) ||
1709                             ($rm_tags == true &&
1710                              !in_array($tagname, $tag_list))){
1711                             $tagname = false;
1712                         } else {
1713                             /**
1714                              * Convert body into div.
1715                              */
1716                             if ($tagname == "body"){
1717                                 $tagname = "div";
1718                                 $attary = sq_body2div($attary, $mailbox,
1719                                                       $message, $id);
1720                             }
1721                             if ($tagtype == 1){
1722                                 if (isset($open_tags{$tagname})){
1723                                     $open_tags{$tagname}++;
1724                                 } else {
1725                                     $open_tags{$tagname}=1;
1726                                 }
1727                             }
1728                             /**
1729                              * This is where we run other checks.
1730                              */
1731                             if (is_array($attary) && sizeof($attary) > 0){
1732                                 $attary = sq_fixatts($tagname,
1733                                                      $attary,
1734                                                      $rm_attnames,
1735                                                      $bad_attvals,
1736                                                      $add_attr_to_tag,
1737                                                      $message,
1738                                                      $id,
1739                                                      $mailbox
1740                                                      );
1741                             }
1742                         }
1743                     }
1744                 }
1745             }
1746             if ($tagname != false && $skip_content == false){
1747                 $trusted .= sq_tagprint($tagname, $attary, $tagtype);
1748             }
1749         }
1750         $curpos = $gt+1;
1751     }
1752     $trusted .= substr($body, $curpos, strlen($body)-$curpos);
1753     if ($force_tag_closing == true){
1754         foreach ($open_tags as $tagname=>$opentimes){
1755             while ($opentimes > 0){
1756                 $trusted .= '</' . $tagname . '>';
1757                 $opentimes--;
1758             }
1759         }
1760         $trusted .= "\n";
1761     }
1762     $trusted .= "<!-- end sanitized html -->\n";
1763     return $trusted;
1764 }
1765
1766 /**
1767  * This is a wrapper function to call html sanitizing routines.
1768  *
1769  * @param  $body  the body of the message
1770  * @param  $id    the id of the message
1771  * @return        a string with html safe to display in the browser.
1772  */
1773 function magicHTML($body, $id, $message, $mailbox = 'INBOX') {
1774     global $attachment_common_show_images, $view_unsafe_images,
1775            $has_unsafe_images;
1776     /**
1777      * Don't display attached images in HTML mode.
1778      */
1779     $attachment_common_show_images = false;
1780     $tag_list = Array(
1781                       false,
1782                       "object",
1783                       "meta",
1784                       "html",
1785                       "head",
1786                       "base",
1787                       "link",
1788                       "frame",
1789                       "iframe",
1790                       "plaintext",
1791                       "marquee"
1792                       );
1793
1794     $rm_tags_with_content = Array(
1795                                   "script",
1796                                   "applet",
1797                                   "embed",
1798                                   "title",
1799                                   "frameset",
1800                                   "xml"
1801                                   );
1802
1803     $self_closing_tags =  Array(
1804                                 "img",
1805                                 "br",
1806                                 "hr",
1807                                 "input"
1808                                 );
1809
1810     $force_tag_closing = true;
1811
1812     $rm_attnames = Array(
1813                          "/.*/" =>
1814                          Array(
1815                                "/target/i",
1816                                "/^on.*/i",
1817                                "/^dynsrc/i",
1818                                "/^data.*/i",
1819                                "/^lowsrc.*/i"
1820                                )
1821                          );
1822
1823     $secremoveimg = "../images/" . _("sec_remove_eng.png");
1824     $bad_attvals = Array(
1825         "/.*/" =>
1826             Array(
1827                 "/^src|background/i" =>
1828                     Array(
1829                           Array(
1830                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1831                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1832                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1833                                 ),
1834                           Array(
1835                                 "\\1$secremoveimg\\2",
1836                                 "\\1$secremoveimg\\2",
1837                                 "\\1$secremoveimg\\2",
1838                                 "\\1$secremoveimg\\2"
1839                                 )
1840                         ),
1841                 "/^href|action/i" =>
1842                     Array(
1843                           Array(
1844                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1845                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1846                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1847                                 ),
1848                           Array(
1849                                 "\\1#\\1",
1850                                 "\\1#\\1",
1851                                 "\\1#\\1",
1852                                 "\\1#\\1"
1853                                 )
1854                         ),
1855                 "/^style/i" =>
1856                     Array(
1857                           Array(
1858                                 "/expression/i",
1859                                 "/binding/i",
1860                                 "/behaviou*r/i",
1861                                 "/include-source/i",
1862                                 "/url\s*\(\s*([\'\"])\s*\S+script\s*:.*([\'\"])\s*\)/si",
1863                                 "/url\s*\(\s*([\'\"])\s*mocha\s*:.*([\'\"])\s*\)/si",
1864                                 "/url\s*\(\s*([\'\"])\s*about\s*:.*([\'\"])\s*\)/si",
1865                                 "/(.*)\s*:\s*url\s*\(\s*([\'\"]*)\s*\S+script\s*:.*([\'\"]*)\s*\)/si"
1866                                ),
1867                           Array(
1868                                 "idiocy",
1869                                 "idiocy",
1870                                 "idiocy",
1871                                 "idiocy",
1872                                 "url(\\1#\\1)",
1873                                 "url(\\1#\\1)",
1874                                 "url(\\1#\\1)",
1875                                 "url(\\1#\\1)",
1876                                 "\\1:url(\\2#\\3)"
1877                                )
1878                           )
1879                 )
1880         );
1881     if( !sqgetGlobalVar('view_unsafe_images', $view_unsafe_images, SQ_GET) ) {
1882         $view_unsafe_images = false;
1883     }
1884     if (!$view_unsafe_images){
1885         /**
1886          * Remove any references to http/https if view_unsafe_images set
1887          * to false.
1888          */
1889          array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[0],
1890                     '/^([\'\"])\s*https*:.*([\'\"])/si');
1891          array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[1],
1892                     "\\1$secremoveimg\\1");
1893          array_push($bad_attvals{'/.*/'}{'/^style/i'}[0],
1894                     '/url\(([\'\"])\s*https*:.*([\'\"])\)/si');
1895          array_push($bad_attvals{'/.*/'}{'/^style/i'}[1],
1896                     "url(\\1$secremoveimg\\1)");
1897     }
1898
1899     $add_attr_to_tag = Array(
1900         "/^a$/i" =>
1901             Array('target'=>'"_new"',
1902                   'title'=>'"'._("This external link will open in a new window").'"'
1903             )
1904     );
1905     $trusted = sq_sanitize($body,
1906                            $tag_list,
1907                            $rm_tags_with_content,
1908                            $self_closing_tags,
1909                            $force_tag_closing,
1910                            $rm_attnames,
1911                            $bad_attvals,
1912                            $add_attr_to_tag,
1913                            $message,
1914                            $id,
1915                            $mailbox
1916                            );
1917     if (preg_match("|$secremoveimg|i", $trusted)){
1918         $has_unsafe_images = true;
1919     }
1920     return $trusted;
1921 }
1922
1923 /**
1924  * function SendDownloadHeaders - send file to the browser
1925  *
1926  * Original Source: SM core src/download.php
1927  * moved here to make it available to other code, and separate
1928  * front end from back end functionality.
1929  *
1930  * @param string $type0 first half of mime type
1931  * @param string $type1 second half of mime type
1932  * @param string $filename filename to tell the browser for downloaded file
1933  * @param boolean $force whether to force the download dialog to pop
1934  * @param optional integer $filesize send the Content-Header and length to the browser
1935  * @return void
1936  */
1937  function SendDownloadHeaders($type0, $type1, $filename, $force, $filesize=0) {
1938      global $languages, $squirrelmail_language;
1939      $isIE = $isIE6 = 0;
1940
1941      sqgetGlobalVar('HTTP_USER_AGENT', $HTTP_USER_AGENT, SQ_SERVER);
1942
1943      if (strstr($HTTP_USER_AGENT, 'compatible; MSIE ') !== false &&
1944          strstr($HTTP_USER_AGENT, 'Opera') === false) {
1945          $isIE = 1;
1946      }
1947
1948      if (strstr($HTTP_USER_AGENT, 'compatible; MSIE 6') !== false &&
1949          strstr($HTTP_USER_AGENT, 'Opera') === false) {
1950          $isIE6 = 1;
1951      }
1952
1953      if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
1954          function_exists($languages[$squirrelmail_language]['XTRA_CODE'])) {
1955          $filename =
1956          $languages[$squirrelmail_language]['XTRA_CODE']('downloadfilename', $filename, $HTTP_USER_AGENT);
1957      } else {
1958          $filename = ereg_replace('[\\/:\*\?"<>\|;]', '_', str_replace('&nbsp;', ' ', $filename));
1959      }
1960
1961      // A Pox on Microsoft and it's Internet Explorer!
1962      //
1963      // IE has lots of bugs with file downloads.
1964      // It also has problems with SSL.  Both of these cause problems
1965      // for us in this function.
1966      //
1967      // See this article on Cache Control headers and SSL
1968      // http://support.microsoft.com/default.aspx?scid=kb;en-us;323308
1969      //
1970      // The best thing you can do for IE is to upgrade to the latest
1971      // version
1972      //set all the Cache Control Headers for IE
1973      if ($isIE && !$isIE6) {
1974          header ("Pragma: public");
1975          header ("Cache-Control: no-store, max-age=0, no-cache, must-revalidate"); # HTTP/1.1
1976          header ("Cache-Control: post-check=0, pre-check=0", false);
1977          header ("Cache-control: private");
1978
1979          //set the inline header for IE, we'll add the attachment header later if we need it
1980          header ("Content-Disposition: inline; filename=$filename");
1981      }
1982
1983      if (!$force) {
1984          // Try to show in browser window
1985          header ("Content-Disposition: inline; filename=\"$filename\"");
1986          header ("Content-Type: $type0/$type1; name=\"$filename\"");
1987      } else {
1988          // Try to pop up the "save as" box
1989
1990          // IE makes this hard.  It pops up 2 save boxes, or none.
1991          // http://support.microsoft.com/support/kb/articles/Q238/5/88.ASP
1992          // http://support.microsoft.com/default.aspx?scid=kb;EN-US;260519
1993          // But, according to Microsoft, it is "RFC compliant but doesn't
1994          // take into account some deviations that allowed within the
1995          // specification."  Doesn't that mean RFC non-compliant?
1996          // http://support.microsoft.com/support/kb/articles/Q258/4/52.ASP
1997
1998          // all browsers need the application/octet-stream header for this
1999          header ("Content-Type: application/octet-stream; name=\"$filename\"");
2000
2001          // http://support.microsoft.com/support/kb/articles/Q182/3/15.asp
2002          // Do not have quotes around filename, but that applied to
2003          // "attachment"... does it apply to inline too?
2004          header ("Content-Disposition: attachment; filename=\"$filename\"");
2005
2006          if ($isIE && !$isIE6) {
2007              // This combination seems to work mostly.  IE 5.5 SP 1 has
2008              // known issues (see the Microsoft Knowledge Base)
2009
2010              // This works for most types, but doesn't work with Word files
2011              header ("Content-Type: application/download; name=\"$filename\"");
2012
2013              // These are spares, just in case.  :-)
2014              //header("Content-Type: $type0/$type1; name=\"$filename\"");
2015              //header("Content-Type: application/x-msdownload; name=\"$filename\"");
2016              //header("Content-Type: application/octet-stream; name=\"$filename\"");
2017          } else {
2018              // another application/octet-stream forces download for Netscape
2019              header ("Content-Type: application/octet-stream; name=\"$filename\"");
2020          }
2021      }
2022
2023      //send the content-length header if the calling function provides it
2024      if ($filesize > 0) {
2025          header("Content-Length: $filesize");
2026      }
2027
2028 }  // end fn SendDownloadHeaders
2029
2030 ?>