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         if ($type0 =='message' && $type1 == 'rfc822') {
 443             $default_page = SM_PATH . 'src/read_body.php';
 444             $rfc822_header = $att->rfc822_header;
 445             $filename = $rfc822_header->subject;
 446             if (trim( $filename ) == '') {
 447                 $filename = 'untitled-[' . $ent . ']' ;
 448             }
 449             $from_o = $rfc822_header->from;
 450             if (is_object($from_o)) {
 451                 $from_name = decodeHeader($from_o->getAddress(false));
 452             } else {
 453                 $from_name = _("Unknown sender");
 454             }
 455             $description = $from_name;
 456         } else {
 457             $default_page = SM_PATH . 'src/download.php';
 458             if (is_object($header->disposition)) {
 459                 $filename = $header->disposition->getProperty('filename');
 460                 if (trim($filename) == '') {
 461                     $name = decodeHeader($header->disposition->getProperty('name'));
 462                     if (trim($name) == '') {
 463                         $name = $header->getParameter('name');
 464                         if(trim($name) == '') {
 465                             if (trim( $header->id ) == '') {
 466                                 $filename = 'untitled-[' . $ent . ']' ;
 467                             } else {
 468                                 $filename = 'cid: ' . $header->id;
 469                             }
 470                         } else {
 471                             $filename = $name;
 472                         }
 473                     } else {
 474                         $filename = $name;
 475                     }
 476                 }
 477             } else {
 478                 $filename = $header->getParameter('name');
 479                 if (!trim($filename)) {
 480                     if (trim( $header->id ) == '') {
 481                         $filename = 'untitled-[' . $ent . ']' ;
 482                     } else {
 483                         $filename = 'cid: ' . $header->id;
 484                     }
 485                 }
 486             }
 487             if ($header->description) {
 488                 $description = decodeHeader($header->description);
 489             } else {
 490                 $description = '';
 491             }
 492         }
 493
 494         $display_filename = $filename;
 495         if (isset($passed_ent_id)) {
 496             $passed_ent_id_link = '&amp;passed_ent_id='.$passed_ent_id;
 497         } else {
 498             $passed_ent_id_link = '';
 499         }
 500         $defaultlink = $default_page . "?startMessage=$startMessage"
 501                      . "&amp;passed_id=$id&amp;mailbox=$urlMailbox"
 502                      . '&amp;ent_id='.$ent.$passed_ent_id_link;
 503         if ($where && $what) {
 504            $defaultlink .= '&amp;where='. urlencode($where).'&amp;what='.urlencode($what);
 505         }
 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>[ '.htmlspecialchars($type0).'/'.htmlspecialchars($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
 552     // Base64 encoded data goes in pairs of 4 bytes. To achieve on the
 553     // fly decoding (to reduce memory usage) you have to check if the
 554     // data has incomplete pairs
 555
 556     // Remove the noise in order to check if the 4 bytes pairs are complete
 557     $string = str_replace(array("\r\n","\n", "\r", " "),array('','','',''),$string);
 558
 559     $sStringRem = '';
 560     $iMod = strlen($string) % 4;
 561     if ($iMod) {
 562         $sStringRem = substr($string,-$iMod);
 563         // Check if $sStringRem contains padding characters
 564         if (substr($sStringRem,-1) != '=') {
 565             $string = substr($string,0,-$iMod);
 566         } else {
 567             $sStringRem = '';
 568         }
 569     }
 570     $string = base64_decode($string);
 571     return $sStringRem;
 572 }
 573
 574
 575 /* This function decodes the body depending on the encoding type. */
 576 function decodeBody($body, $encoding) {
 577     global $show_html_default;
 578
 579     $body = str_replace("\r\n", "\n", $body);
 580     $encoding = strtolower($encoding);
 581
 582     $encoding_handler = do_hook_function('decode_body', $encoding);
 583
 584
 585     // plugins get first shot at decoding the body
 586     //
 587     if (!empty($encoding_handler) && function_exists($encoding_handler)) {
 588         $body = $encoding_handler('decode', $body);
 589
 590     } else if ($encoding == 'quoted-printable' ||
 591         $encoding == 'quoted_printable') {
 592         $body = quoted_printable_decode($body);
 593
 594         while (ereg("=\n", $body)) {
 595             $body = ereg_replace ("=\n", '', $body);
 596         }
 597
 598     } else if ($encoding == 'base64') {
 599         $body = base64_decode($body);
 600     }
 601
 602     // All other encodings are returned raw.
 603     return $body;
 604 }
 605
 606 /**
 607  * Decodes headers
 608  *
 609  * This functions decode strings that is encoded according to
 610  * RFC1522 (MIME Part Two: Message Header Extensions for Non-ASCII Text).
 611  * Patched by Christian Schmidt <christian@ostenfeld.dk>  23/03/2002
 612  *
 613  * @param string $string header string that has to be made readable
 614  * @param boolean $utfencode change message in order to be readable on user's charset. defaults to true
 615  * @param boolean $htmlsave preserve spaces and sanitize html special characters. defaults to true
 616  * @param boolean $decide decide if string can be utfencoded. defaults to false
 617  * @return string decoded header string
 618  */
 619 function decodeHeader ($string, $utfencode=true,$htmlsave=true,$decide=false) {
 620     global $languages, $squirrelmail_language,$default_charset;
 621     if (is_array($string)) {
 622         $string = implode("\n", $string);
 623     }
 624
 625     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 626         function_exists($languages[$squirrelmail_language]['XTRA_CODE'] . '_decodeheader')) {
 627         $string = call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_decodeheader', $string);
 628         // Do we need to return at this point?
 629         // return $string;
 630     }
 631     $i = 0;
 632     $iLastMatch = -2;
 633     $encoded = true;
 634
 635     $aString = explode(' ',$string);
 636     $ret = '';
 637     foreach ($aString as $chunk) {
 638         if ($encoded && $chunk === '') {
 639             continue;
 640         } elseif ($chunk === '') {
 641             $ret .= ' ';
 642             continue;
 643         }
 644         $encoded = false;
 645         /* if encoded words are not separated by a linear-space-white we still catch them */
 646         $j = $i-1;
 647
 648         while ($match = preg_match('/^(.*)=\?([^?]*)\?(Q|B)\?([^?]*)\?=(.*)$/Ui',$chunk,$res)) {
 649             /* if the last chunk isn't an encoded string then put back the space, otherwise don't */
 650             if ($iLastMatch !== $j) {
 651                 if ($htmlsave) {
 652                     $ret .= '&#32;';
 653                 } else {
 654                     $ret .= ' ';
 655                 }
 656             }
 657             $iLastMatch = $i;
 658             $j = $i;
 659             if ($htmlsave) {
 660                 $ret .= htmlspecialchars($res[1]);
 661             } else {
 662                 $ret .= $res[1];
 663             }
 664             $encoding = ucfirst($res[3]);
 665
 666             /* decide about valid decoding */
 667             if ($decide && is_conversion_safe($res[2])) {
 668               $utfencode=true;
 669               $can_be_encoded=true;
 670             } else {
 671               $can_be_encoded=false;
 672             }
 673             switch ($encoding)
 674             {
 675             case 'B':
 676                 $replace = base64_decode($res[4]);
 677                 if ($utfencode) {
 678                     if ($can_be_encoded) {
 679                         /* convert string to different charset,
 680                          * if functions asks for it (usually in compose)
 681                          */
 682                         $ret .= charset_convert($res[2],$replace,$default_charset);
 683                     } else {
 684                         // convert string to html codes in order to display it
 685                         $ret .= charset_decode($res[2],$replace);
 686                     }
 687                 } else {
 688                     if ($htmlsave) {
 689                         $replace = htmlspecialchars($replace);
 690                     }
 691                     $ret.= $replace;
 692                 }
 693                 break;
 694             case 'Q':
 695                 $replace = str_replace('_', ' ', $res[4]);
 696                 $replace = preg_replace('/=([0-9a-f]{2})/ie', 'chr(hexdec("\1"))',
 697                                     $replace);
 698                 if ($utfencode) {
 699                   if ($can_be_encoded) {
 700                     /* convert string to different charset,
 701                      * if functions asks for it (usually in compose)
 702                      */
 703                     $replace = charset_convert($res[2], $replace,$default_charset);
 704                   } else {
 705                     // convert string to html codes in order to display it
 706                     $replace = charset_decode($res[2], $replace);
 707                   }
 708                 } else {
 709                     if ($htmlsave) {
 710                         $replace = htmlspecialchars($replace);
 711                     }
 712                 }
 713                 $ret .= $replace;
 714                 break;
 715             default:
 716                 break;
 717             }
 718             $chunk = $res[5];
 719             $encoded = true;
 720         }
 721         if (!$encoded) {
 722             if ($htmlsave) {
 723                 $ret .= '&#32;';
 724             } else {
 725                 $ret .= ' ';
 726             }
 727         }
 728
 729         if (!$encoded && $htmlsave) {
 730             $ret .= htmlspecialchars($chunk);
 731         } else {
 732             $ret .= $chunk;
 733         }
 734         ++$i;
 735     }
 736     /* remove the first added space */
 737     if ($ret) {
 738         if ($htmlsave) {
 739             $ret = substr($ret,5);
 740         } else {
 741             $ret = substr($ret,1);
 742         }
 743     }
 744
 745     return $ret;
 746 }
 747
 748 /**
 749  * Encodes header as quoted-printable
 750  *
 751  * Encode a string according to RFC 1522 for use in headers if it
 752  * contains 8-bit characters or anything that looks like it should
 753  * be encoded.
 754  *
 755  * @param string $string header string, that has to be encoded
 756  * @return string quoted-printable encoded string
 757  */
 758 function encodeHeader ($string) {
 759     global $default_charset, $languages, $squirrelmail_language;
 760
 761     if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
 762         function_exists($languages[$squirrelmail_language]['XTRA_CODE'] . '_encodeheader')) {
 763         return  call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_encodeheader', $string);
 764     }
 765
 766     // Encode only if the string contains 8-bit characters or =?
 767     $j = strlen($string);
 768     $max_l = 75 - strlen($default_charset) - 7;
 769     $aRet = array();
 770     $ret = '';
 771     $iEncStart = $enc_init = false;
 772     $cur_l = $iOffset = 0;
 773     for($i = 0; $i < $j; ++$i) {
 774         switch($string{$i})
 775         {
 776         case '=':
 777         case '<':
 778         case '>':
 779         case ',':
 780         case '?':
 781         case '_':
 782             if ($iEncStart === false) {
 783                 $iEncStart = $i;
 784             }
 785             $cur_l+=3;
 786             if ($cur_l > ($max_l-2)) {
 787                 /* if there is an stringpart that doesn't need encoding, add it */
 788                 $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 789                 $aRet[] = "=?$default_charset?Q?$ret?=";
 790                 $iOffset = $i;
 791                 $cur_l = 0;
 792                 $ret = '';
 793                 $iEncStart = false;
 794             } else {
 795                 $ret .= sprintf("=%02X",ord($string{$i}));
 796             }
 797             break;
 798         case '(':
 799         case ')':
 800             if ($iEncStart !== false) {
 801                 $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 802                 $aRet[] = "=?$default_charset?Q?$ret?=";
 803                 $iOffset = $i;
 804                 $cur_l = 0;
 805                 $ret = '';
 806                 $iEncStart = false;
 807             }
 808             break;
 809         case ' ':
 810             if ($iEncStart !== false) {
 811                 $cur_l++;
 812                 if ($cur_l > $max_l) {
 813                     $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 814                     $aRet[] = "=?$default_charset?Q?$ret?=";
 815                     $iOffset = $i;
 816                     $cur_l = 0;
 817                     $ret = '';
 818                     $iEncStart = false;
 819                 } else {
 820                     $ret .= '_';
 821                 }
 822             }
 823             break;
 824         default:
 825             $k = ord($string{$i});
 826             if ($k > 126) {
 827                 if ($iEncStart === false) {
 828                     // do not start encoding in the middle of a string, also take the rest of the word.
 829                     $sLeadString = substr($string,0,$i);
 830                     $aLeadString = explode(' ',$sLeadString);
 831                     $sToBeEncoded = array_pop($aLeadString);
 832                     $iEncStart = $i - strlen($sToBeEncoded);
 833                     $ret .= $sToBeEncoded;
 834                     $cur_l += strlen($sToBeEncoded);
 835                 }
 836                 $cur_l += 3;
 837                 /* first we add the encoded string that reached it's max size */
 838                 if ($cur_l > ($max_l-2)) {
 839                     $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 840                     $aRet[] = "=?$default_charset?Q?$ret?= "; /* the next part is also encoded => separate by space */
 841                     $cur_l = 3;
 842                     $ret = '';
 843                     $iOffset = $i;
 844                     $iEncStart = $i;
 845                 }
 846                 $enc_init = true;
 847                 $ret .= sprintf("=%02X", $k);
 848             } else {
 849                 if ($iEncStart !== false) {
 850                     $cur_l++;
 851                     if ($cur_l > $max_l) {
 852                         $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 853                         $aRet[] = "=?$default_charset?Q?$ret?=";
 854                         $iEncStart = false;
 855                         $iOffset = $i;
 856                         $cur_l = 0;
 857                         $ret = '';
 858                     } else {
 859                         $ret .= $string{$i};
 860                     }
 861                 }
 862             }
 863             break;
 864         }
 865     }
 866
 867     if ($enc_init) {
 868         if ($iEncStart !== false) {
 869             $aRet[] = substr($string,$iOffset,$iEncStart-$iOffset);
 870             $aRet[] = "=?$default_charset?Q?$ret?=";
 871         } else {
 872             $aRet[] = substr($string,$iOffset);
 873         }
 874         $string = implode('',$aRet);
 875     }
 876     return $string;
 877 }
 878
 879 /* This function trys to locate the entity_id of a specific mime element */
 880 function find_ent_id($id, $message) {
 881     for ($i = 0, $ret = ''; $ret == '' && $i < count($message->entities); $i++) {
 882         if ($message->entities[$i]->header->type0 == 'multipart')  {
 883             $ret = find_ent_id($id, $message->entities[$i]);
 884         } else {
 885             if (strcasecmp($message->entities[$i]->header->id, $id) == 0) {
 886 //                if (sq_check_save_extension($message->entities[$i])) {
 887                     return $message->entities[$i]->entity_id;
 888 //                }
 889             }
 890         }
 891     }
 892     return $ret;
 893 }
 894
 895 function sq_check_save_extension($message) {
 896     $filename = $message->getFilename();
 897     $ext = substr($filename, strrpos($filename,'.')+1);
 898     $save_extensions = array('jpg','jpeg','gif','png','bmp');
 899     return in_array($ext, $save_extensions);
 900 }
 901
 902
 903 /**
 904  ** HTMLFILTER ROUTINES
 905  */
 906
 907 /**
 908  * This function is more or less a wrapper around stripslashes. Apparently
 909  * Explorer is stupid enough to just remove the backslashes and then
 910  * execute the content of the attribute as if nothing happened.
 911  * Who does that?
 912  *
 913  * @param  attvalue   The value of the attribute
 914  * @return attvalue   The value of the attribute stripslashed.
 915  */
 916 function sq_unbackslash($attvalue){
 917     /**
 918      * Remove any backslashes. See if there are any first.
 919      */
 920
 921     if (strstr($attvalue, '\\') !== false){
 922         $attvalue = stripslashes($attvalue);
 923     }
 924     return $attvalue;
 925 }
 926
 927 /**
 928  * Kill any tabs, newlines, or carriage returns. Our friends the
 929  * makers of the browser with 95% market value decided that it'd
 930  * be funny to make "java[tab]script" be just as good as "javascript".
 931  *
 932  * @param  attvalue  The attribute value before extraneous spaces removed.
 933  * @return attvalue  The attribute value after extraneous spaces removed.
 934  */
 935 function sq_unspace($attvalue){
 936     if (strcspn($attvalue, "\t\r\n") != strlen($attvalue)){
 937         $attvalue = str_replace(Array("\t", "\r", "\n"), Array('', '', ''),
 938                                 $attvalue);
 939     }
 940     return $attvalue;
 941 }
 942
 943 /**
 944  * This function returns the final tag out of the tag name, an array
 945  * of attributes, and the type of the tag. This function is called by
 946  * sq_sanitize internally.
 947  *
 948  * @param  $tagname  the name of the tag.
 949  * @param  $attary   the array of attributes and their values
 950  * @param  $tagtype  The type of the tag (see in comments).
 951  * @return           a string with the final tag representation.
 952  */
 953 function sq_tagprint($tagname, $attary, $tagtype){
 954     $me = 'sq_tagprint';
 955
 956     if ($tagtype == 2){
 957         $fulltag = '</' . $tagname . '>';
 958     } else {
 959         $fulltag = '<' . $tagname;
 960         if (is_array($attary) && sizeof($attary)){
 961             $atts = Array();
 962             while (list($attname, $attvalue) = each($attary)){
 963                 array_push($atts, "$attname=$attvalue");
 964             }
 965             $fulltag .= ' ' . join(" ", $atts);
 966         }
 967         if ($tagtype == 3){
 968             $fulltag .= ' /';
 969         }
 970         $fulltag .= '>';
 971     }
 972     return $fulltag;
 973 }
 974
 975 /**
 976  * A small helper function to use with array_walk. Modifies a by-ref
 977  * value and makes it lowercase.
 978  *
 979  * @param  $val a value passed by-ref.
 980  * @return      void since it modifies a by-ref value.
 981  */
 982 function sq_casenormalize(&$val){
 983     $val = strtolower($val);
 984 }
 985
 986 /**
 987  * This function skips any whitespace from the current position within
 988  * a string and to the next non-whitespace value.
 989  *
 990  * @param  $body   the string
 991  * @param  $offset the offset within the string where we should start
 992  *                 looking for the next non-whitespace character.
 993  * @return         the location within the $body where the next
 994  *                 non-whitespace char is located.
 995  */
 996 function sq_skipspace($body, $offset){
 997     $me = 'sq_skipspace';
 998     preg_match('/^(\s*)/s', substr($body, $offset), $matches);
 999     if (sizeof($matches{1})){
1000         $count = strlen($matches{1});
1001         $offset += $count;
1002     }
1003     return $offset;
1004 }
1005
1006 /**
1007  * This function looks for the next character within a string.  It's
1008  * really just a glorified "strpos", except it catches if failures
1009  * nicely.
1010  *
1011  * @param  $body   The string to look for needle in.
1012  * @param  $offset Start looking from this position.
1013  * @param  $needle The character/string to look for.
1014  * @return         location of the next occurance of the needle, or
1015  *                 strlen($body) if needle wasn't found.
1016  */
1017 function sq_findnxstr($body, $offset, $needle){
1018     $me  = 'sq_findnxstr';
1019     $pos = strpos($body, $needle, $offset);
1020     if ($pos === FALSE){
1021         $pos = strlen($body);
1022     }
1023     return $pos;
1024 }
1025
1026 /**
1027  * This function takes a PCRE-style regexp and tries to match it
1028  * within the string.
1029  *
1030  * @param  $body   The string to look for needle in.
1031  * @param  $offset Start looking from here.
1032  * @param  $reg    A PCRE-style regex to match.
1033  * @return         Returns a false if no matches found, or an array
1034  *                 with the following members:
1035  *                 - integer with the location of the match within $body
1036  *                 - string with whatever content between offset and the match
1037  *                 - string with whatever it is we matched
1038  */
1039 function sq_findnxreg($body, $offset, $reg){
1040     $me = 'sq_findnxreg';
1041     $matches = Array();
1042     $retarr = Array();
1043     preg_match("%^(.*?)($reg)%si", substr($body, $offset), $matches);
1044     if (!isset($matches{0}) || !$matches{0}){
1045         $retarr = false;
1046     } else {
1047         $retarr{0} = $offset + strlen($matches{1});
1048         $retarr{1} = $matches{1};
1049         $retarr{2} = $matches{2};
1050     }
1051     return $retarr;
1052 }
1053
1054 /**
1055  * This function looks for the next tag.
1056  *
1057  * @param  $body   String where to look for the next tag.
1058  * @param  $offset Start looking from here.
1059  * @return         false if no more tags exist in the body, or
1060  *                 an array with the following members:
1061  *                 - string with the name of the tag
1062  *                 - array with attributes and their values
1063  *                 - integer with tag type (1, 2, or 3)
1064  *                 - integer where the tag starts (starting "<")
1065  *                 - integer where the tag ends (ending ">")
1066  *                 first three members will be false, if the tag is invalid.
1067  */
1068 function sq_getnxtag($body, $offset){
1069     $me = 'sq_getnxtag';
1070     if ($offset > strlen($body)){
1071         return false;
1072     }
1073     $lt = sq_findnxstr($body, $offset, "<");
1074     if ($lt == strlen($body)){
1075         return false;
1076     }
1077     /**
1078      * We are here:
1079      * blah blah <tag attribute="value">
1080      * \---------^
1081      */
1082     $pos = sq_skipspace($body, $lt+1);
1083     if ($pos >= strlen($body)){
1084         return Array(false, false, false, $lt, strlen($body));
1085     }
1086     /**
1087      * There are 3 kinds of tags:
1088      * 1. Opening tag, e.g.:
1089      *    <a href="blah">
1090      * 2. Closing tag, e.g.:
1091      *    </a>
1092      * 3. XHTML-style content-less tag, e.g.:
1093      *    <img src="blah" />
1094      */
1095     $tagtype = false;
1096     switch (substr($body, $pos, 1)){
1097         case '/':
1098             $tagtype = 2;
1099             $pos++;
1100             break;
1101         case '!':
1102             /**
1103              * A comment or an SGML declaration.
1104              */
1105             if (substr($body, $pos+1, 2) == "--"){
1106                 $gt = strpos($body, "-->", $pos);
1107                 if ($gt === false){
1108                     $gt = strlen($body);
1109                 } else {
1110                     $gt += 2;
1111                 }
1112                 return Array(false, false, false, $lt, $gt);
1113             } else {
1114                 $gt = sq_findnxstr($body, $pos, ">");
1115                 return Array(false, false, false, $lt, $gt);
1116             }
1117             break;
1118         default:
1119             /**
1120              * Assume tagtype 1 for now. If it's type 3, we'll switch values
1121              * later.
1122              */
1123             $tagtype = 1;
1124             break;
1125     }
1126
1127     $tagname = '';
1128     /**
1129      * Look for next [\W-_], which will indicate the end of the tag name.
1130      */
1131     $regary = sq_findnxreg($body, $pos, "[^\w\-_]");
1132     if ($regary == false){
1133         return Array(false, false, false, $lt, strlen($body));
1134     }
1135     list($pos, $tagname, $match) = $regary;
1136     $tagname = strtolower($tagname);
1137
1138     /**
1139      * $match can be either of these:
1140      * '>'  indicating the end of the tag entirely.
1141      * '\s' indicating the end of the tag name.
1142      * '/'  indicating that this is type-3 xhtml tag.
1143      *
1144      * Whatever else we find there indicates an invalid tag.
1145      */
1146     switch ($match){
1147         case '/':
1148             /**
1149              * This is an xhtml-style tag with a closing / at the
1150              * end, like so: <img src="blah" />. Check if it's followed
1151              * by the closing bracket. If not, then this tag is invalid
1152              */
1153             if (substr($body, $pos, 2) == "/>"){
1154                 $pos++;
1155                 $tagtype = 3;
1156             } else {
1157                 $gt = sq_findnxstr($body, $pos, ">");
1158                 $retary = Array(false, false, false, $lt, $gt);
1159                 return $retary;
1160             }
1161         case '>':
1162             return Array($tagname, false, $tagtype, $lt, $pos);
1163             break;
1164         default:
1165             /**
1166              * Check if it's whitespace
1167              */
1168             if (!preg_match('/\s/', $match)){
1169                 /**
1170                  * This is an invalid tag! Look for the next closing ">".
1171                  */
1172                 $gt = sq_findnxstr($body, $lt, ">");
1173                 return Array(false, false, false, $lt, $gt);
1174             }
1175             break;
1176     }
1177
1178     /**
1179      * At this point we're here:
1180      * <tagname  attribute='blah'>
1181      * \-------^
1182      *
1183      * At this point we loop in order to find all attributes.
1184      */
1185     $attname = '';
1186     $attary = Array();
1187
1188     while ($pos <= strlen($body)){
1189         $pos = sq_skipspace($body, $pos);
1190         if ($pos == strlen($body)){
1191             /**
1192              * Non-closed tag.
1193              */
1194             return Array(false, false, false, $lt, $pos);
1195         }
1196         /**
1197          * See if we arrived at a ">" or "/>", which means that we reached
1198          * the end of the tag.
1199          */
1200         $matches = Array();
1201         if (preg_match("%^(\s*)(>|/>)%s", substr($body, $pos), $matches)) {
1202             /**
1203              * Yep. So we did.
1204              */
1205             $pos += strlen($matches{1});
1206             if ($matches{2} == "/>"){
1207                 $tagtype = 3;
1208                 $pos++;
1209             }
1210             return Array($tagname, $attary, $tagtype, $lt, $pos);
1211         }
1212
1213         /**
1214          * There are several types of attributes, with optional
1215          * [:space:] between members.
1216          * Type 1:
1217          *   attrname[:space:]=[:space:]'CDATA'
1218          * Type 2:
1219          *   attrname[:space:]=[:space:]"CDATA"
1220          * Type 3:
1221          *   attr[:space:]=[:space:]CDATA
1222          * Type 4:
1223          *   attrname
1224          *
1225          * We leave types 1 and 2 the same, type 3 we check for
1226          * '"' and convert to "&quot" if needed, then wrap in
1227          * double quotes. Type 4 we convert into:
1228          * attrname="yes".
1229          */
1230         $regary = sq_findnxreg($body, $pos, "[^:\w\-_]");
1231         if ($regary == false){
1232             /**
1233              * Looks like body ended before the end of tag.
1234              */
1235             return Array(false, false, false, $lt, strlen($body));
1236         }
1237         list($pos, $attname, $match) = $regary;
1238         $attname = strtolower($attname);
1239         /**
1240          * We arrived at the end of attribute name. Several things possible
1241          * here:
1242          * '>'  means the end of the tag and this is attribute type 4
1243          * '/'  if followed by '>' means the same thing as above
1244          * '\s' means a lot of things -- look what it's followed by.
1245          *      anything else means the attribute is invalid.
1246          */
1247         switch($match){
1248             case '/':
1249                 /**
1250                  * This is an xhtml-style tag with a closing / at the
1251                  * end, like so: <img src="blah" />. Check if it's followed
1252                  * by the closing bracket. If not, then this tag is invalid
1253                  */
1254                 if (substr($body, $pos, 2) == "/>"){
1255                     $pos++;
1256                     $tagtype = 3;
1257                 } else {
1258                     $gt = sq_findnxstr($body, $pos, ">");
1259                     $retary = Array(false, false, false, $lt, $gt);
1260                     return $retary;
1261                 }
1262             case '>':
1263                 $attary{$attname} = '"yes"';
1264                 return Array($tagname, $attary, $tagtype, $lt, $pos);
1265                 break;
1266             default:
1267                 /**
1268                  * Skip whitespace and see what we arrive at.
1269                  */
1270                 $pos = sq_skipspace($body, $pos);
1271                 $char = substr($body, $pos, 1);
1272                 /**
1273                  * Two things are valid here:
1274                  * '=' means this is attribute type 1 2 or 3.
1275                  * \w means this was attribute type 4.
1276                  * anything else we ignore and re-loop. End of tag and
1277                  * invalid stuff will be caught by our checks at the beginning
1278                  * of the loop.
1279                  */
1280                 if ($char == "="){
1281                     $pos++;
1282                     $pos = sq_skipspace($body, $pos);
1283                     /**
1284                      * Here are 3 possibilities:
1285                      * "'"  attribute type 1
1286                      * '"'  attribute type 2
1287                      * everything else is the content of tag type 3
1288                      */
1289                     $quot = substr($body, $pos, 1);
1290                     if ($quot == "'"){
1291                         $regary = sq_findnxreg($body, $pos+1, "\'");
1292                         if ($regary == false){
1293                             return Array(false, false, false, $lt, strlen($body));
1294                         }
1295                         list($pos, $attval, $match) = $regary;
1296                         $pos++;
1297                         $attary{$attname} = "'" . $attval . "'";
1298                     } else if ($quot == '"'){
1299                         $regary = sq_findnxreg($body, $pos+1, '\"');
1300                         if ($regary == false){
1301                             return Array(false, false, false, $lt, strlen($body));
1302                         }
1303                         list($pos, $attval, $match) = $regary;
1304                         $pos++;
1305                         $attary{$attname} = '"' . $attval . '"';
1306                     } else {
1307                         /**
1308                          * These are hateful. Look for \s, or >.
1309                          */
1310                         $regary = sq_findnxreg($body, $pos, "[\s>]");
1311                         if ($regary == false){
1312                             return Array(false, false, false, $lt, strlen($body));
1313                         }
1314                         list($pos, $attval, $match) = $regary;
1315                         /**
1316                          * If it's ">" it will be caught at the top.
1317                          */
1318                         $attval = preg_replace("/\"/s", "&quot;", $attval);
1319                         $attary{$attname} = '"' . $attval . '"';
1320                     }
1321                 } else if (preg_match("|[\w/>]|", $char)) {
1322                     /**
1323                      * That was attribute type 4.
1324                      */
1325                     $attary{$attname} = '"yes"';
1326                 } else {
1327                     /**
1328                      * An illegal character. Find next '>' and return.
1329                      */
1330                     $gt = sq_findnxstr($body, $pos, ">");
1331                     return Array(false, false, false, $lt, $gt);
1332                 }
1333                 break;
1334         }
1335     }
1336     /**
1337      * The fact that we got here indicates that the tag end was never
1338      * found. Return invalid tag indication so it gets stripped.
1339      */
1340     return Array(false, false, false, $lt, strlen($body));
1341 }
1342
1343 /**
1344  * This function checks attribute values for entity-encoded values
1345  * and returns them translated into 8-bit strings so we can run
1346  * checks on them.
1347  *
1348  * @param  $attvalue A string to run entity check against.
1349  * @return           Translated value.
1350  */
1351
1352 function sq_deent($attvalue){
1353     $me = 'sq_deent';
1354     /**
1355      * See if we have to run the checks first. All entities must start
1356      * with "&".
1357      */
1358     if (strpos($attvalue, '&') === false){
1359         return $attvalue;
1360     }
1361     /**
1362      * Check named entities first.
1363      */
1364     $trans = get_html_translation_table(HTML_ENTITIES);
1365     /**
1366      * Leave &quot; in, as it can mess us up.
1367      */
1368     $trans = array_flip($trans);
1369     unset($trans{'&quot;'});
1370     while (list($ent, $val) = each($trans)){
1371         $attvalue = preg_replace('/' . $ent . '*/si', $val, $attvalue);
1372     }
1373     /**
1374      * Now translate numbered entities from 1 to 255 if needed.
1375      */
1376     if (strpos($attvalue, '#') !== false){
1377         $omit = Array(34, 39);
1378         for ($asc = 256; $asc >= 0; $asc--){
1379             if (!in_array($asc, $omit)){
1380                 $chr = chr($asc);
1381                 $octrule = '/\&#0*' . $asc . ';*/si';
1382                 $hexrule = '/\&#x0*' . dechex($asc) . ';*/si';
1383                 $attvalue = preg_replace($octrule, $chr, $attvalue);
1384                 $attvalue = preg_replace($hexrule, $chr, $attvalue);
1385             }
1386         }
1387     }
1388     return $attvalue;
1389 }
1390
1391 /**
1392  * This function runs various checks against the attributes.
1393  *
1394  * @param  $tagname         String with the name of the tag.
1395  * @param  $attary          Array with all tag attributes.
1396  * @param  $rm_attnames     See description for sq_sanitize
1397  * @param  $bad_attvals     See description for sq_sanitize
1398  * @param  $add_attr_to_tag See description for sq_sanitize
1399  * @param  $message         message object
1400  * @param  $id              message id
1401  * @return                  Array with modified attributes.
1402  */
1403 function sq_fixatts($tagname,
1404                     $attary,
1405                     $rm_attnames,
1406                     $bad_attvals,
1407                     $add_attr_to_tag,
1408                     $message,
1409                     $id,
1410                     $mailbox
1411                     ){
1412     $me = 'sq_fixatts';
1413     while (list($attname, $attvalue) = each($attary)){
1414         /**
1415          * See if this attribute should be removed.
1416          */
1417         foreach ($rm_attnames as $matchtag=>$matchattrs){
1418             if (preg_match($matchtag, $tagname)){
1419                 foreach ($matchattrs as $matchattr){
1420                     if (preg_match($matchattr, $attname)){
1421                         unset($attary{$attname});
1422                         continue;
1423                     }
1424                 }
1425             }
1426         }
1427         /**
1428          * Remove any backslashes, entities, and extraneous whitespace.
1429          */
1430         $attvalue = sq_unbackslash($attvalue);
1431         $attvalue = sq_deent($attvalue);
1432         $attvalue = sq_unspace($attvalue);
1433
1434         /**
1435          * Remove \r \n \t \0 " " "\\"
1436          */
1437         $attvalue = str_replace(Array("\r", "\n", "\t", "\0", " ", "\\"),
1438                         Array('', '','','','',''), $attvalue);
1439
1440         /**
1441          * Now let's run checks on the attvalues.
1442          * I don't expect anyone to comprehend this. If you do,
1443          * get in touch with me so I can drive to where you live and
1444          * shake your hand personally. :)
1445          */
1446         foreach ($bad_attvals as $matchtag=>$matchattrs){
1447             if (preg_match($matchtag, $tagname)){
1448                 foreach ($matchattrs as $matchattr=>$valary){
1449                     if (preg_match($matchattr, $attname)){
1450                         /**
1451                          * There are two arrays in valary.
1452                          * First is matches.
1453                          * Second one is replacements
1454                          */
1455                         list($valmatch, $valrepl) = $valary;
1456                         $newvalue =
1457                             preg_replace($valmatch, $valrepl, $attvalue);
1458                         if ($newvalue != $attvalue){
1459                             $attary{$attname} = $newvalue;
1460                         }
1461                     }
1462                 }
1463             }
1464         }
1465         /**
1466          * Turn cid: urls into http-friendly ones.
1467          */
1468         if (preg_match("/^[\'\"]\s*cid:/si", $attvalue)){
1469             $attary{$attname} = sq_cid2http($message, $id, $attvalue, $mailbox);
1470         }
1471     }
1472     /**
1473      * See if we need to append any attributes to this tag.
1474      */
1475     foreach ($add_attr_to_tag as $matchtag=>$addattary){
1476         if (preg_match($matchtag, $tagname)){
1477             $attary = array_merge($attary, $addattary);
1478         }
1479     }
1480     return $attary;
1481 }
1482
1483 /**
1484  * This function edits the style definition to make them friendly and
1485  * usable in squirrelmail.
1486  *
1487  * @param  $message  the message object
1488  * @param  $id       the message id
1489  * @param  $content  a string with whatever is between <style> and </style>
1490  * @param  $mailbox  the message mailbox
1491  * @return           a string with edited content.
1492  */
1493 function sq_fixstyle($body, $pos, $message, $id, $mailbox){
1494     global $view_unsafe_images;
1495     $me = 'sq_fixstyle';
1496     $ret = sq_findnxreg($body, $pos, '</\s*style\s*>');
1497     if ($ret == FALSE){
1498         return array(FALSE, strlen($body));
1499     }
1500     $newpos = $ret[0] + strlen($ret[2]);
1501     $content = $ret[1];
1502     /**
1503      * First look for general BODY style declaration, which would be
1504      * like so:
1505      * body {background: blah-blah}
1506      * and change it to .bodyclass so we can just assign it to a <div>
1507      */
1508     $content = preg_replace("|body(\s*\{.*?\})|si", ".bodyclass\\1", $content);
1509     $secremoveimg = '../images/' . _("sec_remove_eng.png");
1510     /**
1511      * Fix url('blah') declarations.
1512      */
1513     $content = preg_replace("|url\s*\(\s*([\'\"])\s*\S+script\s*:.*?([\'\"])\s*\)|si",
1514                             "url(\\1$secremoveimg\\2)", $content);
1515     /**
1516      * Fix url('https*://.*) declarations but only if $view_unsafe_images
1517      * is false.
1518      */
1519     if (!$view_unsafe_images){
1520         $content = preg_replace("|url\s*\(\s*([\'\"])\s*https*:.*?([\'\"])\s*\)|si",
1521                                 "url(\\1$secremoveimg\\2)", $content);
1522     }
1523
1524     /**
1525      * Fix urls that refer to cid:
1526      */
1527     while (preg_match("|url\s*\(\s*([\'\"]\s*cid:.*?[\'\"])\s*\)|si",
1528                       $content, $matches)){
1529         $cidurl = $matches{1};
1530         $httpurl = sq_cid2http($message, $id, $cidurl, $mailbox);
1531         $content = preg_replace("|url\s*\(\s*$cidurl\s*\)|si",
1532                                 "url($httpurl)", $content);
1533     }
1534
1535     /**
1536      * Fix stupid css declarations which lead to vulnerabilities
1537      * in IE.
1538      */
1539     $match   = Array('/expression/i',
1540                      '/behaviou*r/i',
1541                      '/binding/i',
1542                      '/include-source/i');
1543     $replace = Array('idiocy', 'idiocy', 'idiocy', 'idiocy');
1544     $content = preg_replace($match, $replace, $content);
1545     return array($content, $newpos);
1546 }
1547
1548 /**
1549  * This function converts cid: url's into the ones that can be viewed in
1550  * the browser.
1551  *
1552  * @param  $message  the message object
1553  * @param  $id       the message id
1554  * @param  $cidurl   the cid: url.
1555  * @param  $mailbox  the message mailbox
1556  * @return           a string with a http-friendly url
1557  */
1558 function sq_cid2http($message, $id, $cidurl, $mailbox){
1559     /**
1560      * Get rid of quotes.
1561      */
1562     $quotchar = substr($cidurl, 0, 1);
1563     if ($quotchar == '"' || $quotchar == "'"){
1564         $cidurl = str_replace($quotchar, "", $cidurl);
1565     } else {
1566         $quotchar = '';
1567     }
1568     $cidurl = substr(trim($cidurl), 4);
1569     $linkurl = find_ent_id($cidurl, $message);
1570     /* in case of non-save cid links $httpurl should be replaced by a sort of
1571        unsave link image */
1572     $httpurl = '';
1573     if ($linkurl) {
1574         $httpurl = $quotchar . SM_PATH . 'src/download.php?absolute_dl=true&amp;' .
1575                    "passed_id=$id&amp;mailbox=" . urlencode($mailbox) .
1576                    '&amp;ent_id=' . $linkurl . $quotchar;
1577     }
1578     return $httpurl;
1579 }
1580
1581 /**
1582  * This function changes the <body> tag into a <div> tag since we
1583  * can't really have a body-within-body.
1584  *
1585  * @param  $attary   an array of attributes and values of <body>
1586  * @param  $mailbox  mailbox we're currently reading (for cid2http)
1587  * @param  $message  current message (for cid2http)
1588  * @param  $id       current message id (for cid2http)
1589  * @return           a modified array of attributes to be set for <div>
1590  */
1591 function sq_body2div($attary, $mailbox, $message, $id){
1592     $me = 'sq_body2div';
1593     $divattary = Array('class' => "'bodyclass'");
1594     $text = '#000000';
1595     $has_bgc_stl = $has_txt_stl = false;
1596     $styledef = '';
1597     if (is_array($attary) && sizeof($attary) > 0){
1598         foreach ($attary as $attname=>$attvalue){
1599             $quotchar = substr($attvalue, 0, 1);
1600             $attvalue = str_replace($quotchar, "", $attvalue);
1601             switch ($attname){
1602                 case 'background':
1603                     $attvalue = sq_cid2http($message, $id,
1604                                             $attvalue, $mailbox);
1605                     $styledef .= "background-image: url('$attvalue'); ";
1606                     break;
1607                 case 'bgcolor':
1608                     $has_bgc_stl = true;
1609                     $styledef .= "background-color: $attvalue; ";
1610                     break;
1611                 case 'text':
1612                     $has_txt_stl = true;
1613                     $styledef .= "color: $attvalue; ";
1614                     break;
1615             }
1616         }
1617         // Outlook defines a white bgcolor and no text color. This can lead to
1618         // white text on a white bg with certain themes.
1619         if ($has_bgc_stl && !$has_txt_stl) {
1620             $styledef .= "color: $text; ";
1621         }
1622         if (strlen($styledef) > 0){
1623             $divattary{"style"} = "\"$styledef\"";
1624         }
1625     }
1626     return $divattary;
1627 }
1628
1629 /**
1630  * This is the main function and the one you should actually be calling.
1631  * There are several variables you should be aware of an which need
1632  * special description.
1633  *
1634  * Since the description is quite lengthy, see it here:
1635  * http://linux.duke.edu/projects/mini/htmlfilter/
1636  *
1637  * @param $body                 the string with HTML you wish to filter
1638  * @param $tag_list             see description above
1639  * @param $rm_tags_with_content see description above
1640  * @param $self_closing_tags    see description above
1641  * @param $force_tag_closing    see description above
1642  * @param $rm_attnames          see description above
1643  * @param $bad_attvals          see description above
1644  * @param $add_attr_to_tag      see description above
1645  * @param $message              message object
1646  * @param $id                   message id
1647  * @return                      sanitized html safe to show on your pages.
1648  */
1649 function sq_sanitize($body,
1650                      $tag_list,
1651                      $rm_tags_with_content,
1652                      $self_closing_tags,
1653                      $force_tag_closing,
1654                      $rm_attnames,
1655                      $bad_attvals,
1656                      $add_attr_to_tag,
1657                      $message,
1658                      $id,
1659                      $mailbox
1660                      ){
1661     $me = 'sq_sanitize';
1662     $rm_tags = array_shift($tag_list);
1663     /**
1664      * Normalize rm_tags and rm_tags_with_content.
1665      */
1666     @array_walk($tag_list, 'sq_casenormalize');
1667     @array_walk($rm_tags_with_content, 'sq_casenormalize');
1668     @array_walk($self_closing_tags, 'sq_casenormalize');
1669     /**
1670      * See if tag_list is of tags to remove or tags to allow.
1671      * false  means remove these tags
1672      * true   means allow these tags
1673      */
1674     $curpos = 0;
1675     $open_tags = Array();
1676     $trusted = "\n<!-- begin sanitized html -->\n";
1677     $skip_content = false;
1678     /**
1679      * Take care of netscape's stupid javascript entities like
1680      * &{alert('boo')};
1681      */
1682     $body = preg_replace("/&(\{.*?\};)/si", "&amp;\\1", $body);
1683
1684     while (($curtag = sq_getnxtag($body, $curpos)) != FALSE){
1685         list($tagname, $attary, $tagtype, $lt, $gt) = $curtag;
1686         $free_content = substr($body, $curpos, $lt-$curpos);
1687         /**
1688          * Take care of <style>
1689          */
1690         if ($tagname == "style" && $tagtype == 1){
1691             list($free_content, $curpos) =
1692                 sq_fixstyle($body, $gt+1, $message, $id, $mailbox);
1693             if ($free_content != FALSE){
1694                 $trusted .= sq_tagprint($tagname, $attary, $tagtype);
1695                 $trusted .= $free_content;
1696                 $trusted .= sq_tagprint($tagname, false, 2);
1697             }
1698             continue;
1699         }
1700         if ($skip_content == false){
1701             $trusted .= $free_content;
1702         }
1703         if ($tagname != FALSE){
1704             if ($tagtype == 2){
1705                 if ($skip_content == $tagname){
1706                     /**
1707                      * Got to the end of tag we needed to remove.
1708                      */
1709                     $tagname = false;
1710                     $skip_content = false;
1711                 } else {
1712                     if ($skip_content == false){
1713                         if ($tagname == "body"){
1714                             $tagname = "div";
1715                         }
1716                         if (isset($open_tags{$tagname}) &&
1717                             $open_tags{$tagname} > 0){
1718                             $open_tags{$tagname}--;
1719                         } else {
1720                             $tagname = false;
1721                         }
1722                     }
1723                 }
1724             } else {
1725                 /**
1726                  * $rm_tags_with_content
1727                  */
1728                 if ($skip_content == false){
1729                     /**
1730                      * See if this is a self-closing type and change
1731                      * tagtype appropriately.
1732                      */
1733                     if ($tagtype == 1
1734                         && in_array($tagname, $self_closing_tags)){
1735                         $tagtype = 3;
1736                     }
1737                     /**
1738                      * See if we should skip this tag and any content
1739                      * inside it.
1740                      */
1741                     if ($tagtype == 1 &&
1742                         in_array($tagname, $rm_tags_with_content)){
1743                         $skip_content = $tagname;
1744                     } else {
1745                         if (($rm_tags == false
1746                              && in_array($tagname, $tag_list)) ||
1747                             ($rm_tags == true &&
1748                              !in_array($tagname, $tag_list))){
1749                             $tagname = false;
1750                         } else {
1751                             /**
1752                              * Convert body into div.
1753                              */
1754                             if ($tagname == "body"){
1755                                 $tagname = "div";
1756                                 $attary = sq_body2div($attary, $mailbox,
1757                                                       $message, $id);
1758                             }
1759                             if ($tagtype == 1){
1760                                 if (isset($open_tags{$tagname})){
1761                                     $open_tags{$tagname}++;
1762                                 } else {
1763                                     $open_tags{$tagname}=1;
1764                                 }
1765                             }
1766                             /**
1767                              * This is where we run other checks.
1768                              */
1769                             if (is_array($attary) && sizeof($attary) > 0){
1770                                 $attary = sq_fixatts($tagname,
1771                                                      $attary,
1772                                                      $rm_attnames,
1773                                                      $bad_attvals,
1774                                                      $add_attr_to_tag,
1775                                                      $message,
1776                                                      $id,
1777                                                      $mailbox
1778                                                      );
1779                             }
1780                         }
1781                     }
1782                 }
1783             }
1784             if ($tagname != false && $skip_content == false){
1785                 $trusted .= sq_tagprint($tagname, $attary, $tagtype);
1786             }
1787         }
1788         $curpos = $gt+1;
1789     }
1790     $trusted .= substr($body, $curpos, strlen($body)-$curpos);
1791     if ($force_tag_closing == true){
1792         foreach ($open_tags as $tagname=>$opentimes){
1793             while ($opentimes > 0){
1794                 $trusted .= '</' . $tagname . '>';
1795                 $opentimes--;
1796             }
1797         }
1798         $trusted .= "\n";
1799     }
1800     $trusted .= "<!-- end sanitized html -->\n";
1801     return $trusted;
1802 }
1803
1804 /**
1805  * This is a wrapper function to call html sanitizing routines.
1806  *
1807  * @param  $body  the body of the message
1808  * @param  $id    the id of the message
1809  * @return        a string with html safe to display in the browser.
1810  */
1811 function magicHTML($body, $id, $message, $mailbox = 'INBOX') {
1812     global $attachment_common_show_images, $view_unsafe_images,
1813            $has_unsafe_images;
1814     /**
1815      * Don't display attached images in HTML mode.
1816      */
1817     $attachment_common_show_images = false;
1818     $tag_list = Array(
1819                       false,
1820                       "object",
1821                       "meta",
1822                       "html",
1823                       "head",
1824                       "base",
1825                       "link",
1826                       "frame",
1827                       "iframe",
1828                       "plaintext",
1829                       "marquee"
1830                       );
1831
1832     $rm_tags_with_content = Array(
1833                                   "script",
1834                                   "applet",
1835                                   "embed",
1836                                   "title",
1837                                   "frameset",
1838                                   "xml"
1839                                   );
1840
1841     $self_closing_tags =  Array(
1842                                 "img",
1843                                 "br",
1844                                 "hr",
1845                                 "input"
1846                                 );
1847
1848     $force_tag_closing = true;
1849
1850     $rm_attnames = Array(
1851                          "/.*/" =>
1852                          Array(
1853                                "/target/i",
1854                                "/^on.*/i",
1855                                "/^dynsrc/i",
1856                                "/^data.*/i",
1857                                "/^lowsrc.*/i"
1858                                )
1859                          );
1860
1861     $secremoveimg = "../images/" . _("sec_remove_eng.png");
1862     $bad_attvals = Array(
1863         "/.*/" =>
1864             Array(
1865                 "/^src|background/i" =>
1866                     Array(
1867                           Array(
1868                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1869                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1870                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1871                                 ),
1872                           Array(
1873                                 "\\1$secremoveimg\\2",
1874                                 "\\1$secremoveimg\\2",
1875                                 "\\1$secremoveimg\\2",
1876                                 "\\1$secremoveimg\\2"
1877                                 )
1878                         ),
1879                 "/^href|action/i" =>
1880                     Array(
1881                           Array(
1882                                 "/^([\'\"])\s*\S+script\s*:.*([\'\"])/si",
1883                                 "/^([\'\"])\s*mocha\s*:*.*([\'\"])/si",
1884                                 "/^([\'\"])\s*about\s*:.*([\'\"])/si"
1885                                 ),
1886                           Array(
1887                                 "\\1#\\1",
1888                                 "\\1#\\1",
1889                                 "\\1#\\1",
1890                                 "\\1#\\1"
1891                                 )
1892                         ),
1893                 "/^style/i" =>
1894                     Array(
1895                           Array(
1896                                 "/expression/i",
1897                                 "/binding/i",
1898                                 "/behaviou*r/i",
1899                                 "/include-source/i",
1900                                 "/url\s*\(\s*([\'\"])\s*\S+script\s*:.*([\'\"])\s*\)/si",
1901                                 "/url\s*\(\s*([\'\"])\s*mocha\s*:.*([\'\"])\s*\)/si",
1902                                 "/url\s*\(\s*([\'\"])\s*about\s*:.*([\'\"])\s*\)/si",
1903                                 "/(.*)\s*:\s*url\s*\(\s*([\'\"]*)\s*\S+script\s*:.*([\'\"]*)\s*\)/si"
1904                                ),
1905                           Array(
1906                                 "idiocy",
1907                                 "idiocy",
1908                                 "idiocy",
1909                                 "idiocy",
1910                                 "url(\\1#\\1)",
1911                                 "url(\\1#\\1)",
1912                                 "url(\\1#\\1)",
1913                                 "url(\\1#\\1)",
1914                                 "\\1:url(\\2#\\3)"
1915                                )
1916                           )
1917                 )
1918         );
1919     if( !sqgetGlobalVar('view_unsafe_images', $view_unsafe_images, SQ_GET) ) {
1920         $view_unsafe_images = false;
1921     }
1922     if (!$view_unsafe_images){
1923         /**
1924          * Remove any references to http/https if view_unsafe_images set
1925          * to false.
1926          */
1927          array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[0],
1928                     '/^([\'\"])\s*https*:.*([\'\"])/si');
1929          array_push($bad_attvals{'/.*/'}{'/^src|background/i'}[1],
1930                     "\\1$secremoveimg\\1");
1931          array_push($bad_attvals{'/.*/'}{'/^style/i'}[0],
1932                     '/url\(([\'\"])\s*https*:.*([\'\"])\)/si');
1933          array_push($bad_attvals{'/.*/'}{'/^style/i'}[1],
1934                     "url(\\1$secremoveimg\\1)");
1935     }
1936
1937     $add_attr_to_tag = Array(
1938         "/^a$/i" =>
1939             Array('target'=>'"_new"',
1940                   'title'=>'"'._("This external link will open in a new window").'"'
1941             )
1942     );
1943     $trusted = sq_sanitize($body,
1944                            $tag_list,
1945                            $rm_tags_with_content,
1946                            $self_closing_tags,
1947                            $force_tag_closing,
1948                            $rm_attnames,
1949                            $bad_attvals,
1950                            $add_attr_to_tag,
1951                            $message,
1952                            $id,
1953                            $mailbox
1954                            );
1955     if (preg_match("|$secremoveimg|i", $trusted)){
1956         $has_unsafe_images = true;
1957     }
1958     return $trusted;
1959 }
1960
1961 /**
1962  * function SendDownloadHeaders - send file to the browser
1963  *
1964  * Original Source: SM core src/download.php
1965  * moved here to make it available to other code, and separate
1966  * front end from back end functionality.
1967  *
1968  * @param string $type0 first half of mime type
1969  * @param string $type1 second half of mime type
1970  * @param string $filename filename to tell the browser for downloaded file
1971  * @param boolean $force whether to force the download dialog to pop
1972  * @param optional integer $filesize send the Content-Header and length to the browser
1973  * @return void
1974  */
1975  function SendDownloadHeaders($type0, $type1, $filename, $force, $filesize=0) {
1976      global $languages, $squirrelmail_language;
1977      $isIE = $isIE6 = 0;
1978
1979      sqgetGlobalVar('HTTP_USER_AGENT', $HTTP_USER_AGENT, SQ_SERVER);
1980
1981      if (strstr($HTTP_USER_AGENT, 'compatible; MSIE ') !== false &&
1982          strstr($HTTP_USER_AGENT, 'Opera') === false) {
1983          $isIE = 1;
1984      }
1985
1986      if (strstr($HTTP_USER_AGENT, 'compatible; MSIE 6') !== false &&
1987          strstr($HTTP_USER_AGENT, 'Opera') === false) {
1988          $isIE6 = 1;
1989      }
1990
1991      if (isset($languages[$squirrelmail_language]['XTRA_CODE']) &&
1992          function_exists($languages[$squirrelmail_language]['XTRA_CODE'] . '_downloadfilename')) {
1993          $filename =
1994          call_user_func($languages[$squirrelmail_language]['XTRA_CODE'] . '_downloadfilename', $filename, $HTTP_USER_AGENT);
1995      } else {
1996          $filename = ereg_replace('[\\/:\*\?"<>\|;]', '_', str_replace('&nbsp;', ' ', $filename));
1997      }
1998
1999      // A Pox on Microsoft and it's Internet Explorer!
2000      //
2001      // IE has lots of bugs with file downloads.
2002      // It also has problems with SSL.  Both of these cause problems
2003      // for us in this function.
2004      //
2005      // See this article on Cache Control headers and SSL
2006      // http://support.microsoft.com/default.aspx?scid=kb;en-us;323308
2007      //
2008      // The best thing you can do for IE is to upgrade to the latest
2009      // version
2010      //set all the Cache Control Headers for IE
2011      if ($isIE) {
2012          $filename=urlencode($filename);
2013          header ("Pragma: public");
2014          header ("Cache-Control: no-store, max-age=0, no-cache, must-revalidate"); # HTTP/1.1
2015          header ("Cache-Control: post-check=0, pre-check=0", false);
2016          header ("Cache-control: private");
2017
2018          //set the inline header for IE, we'll add the attachment header later if we need it
2019          header ("Content-Disposition: inline; filename=$filename");
2020      }
2021
2022      if (!$force) {
2023          // Try to show in browser window
2024          header ("Content-Disposition: inline; filename=\"$filename\"");
2025          header ("Content-Type: $type0/$type1; name=\"$filename\"");
2026      } else {
2027          // Try to pop up the "save as" box
2028
2029          // IE makes this hard.  It pops up 2 save boxes, or none.
2030          // http://support.microsoft.com/support/kb/articles/Q238/5/88.ASP
2031          // http://support.microsoft.com/default.aspx?scid=kb;EN-US;260519
2032          // But, according to Microsoft, it is "RFC compliant but doesn't
2033          // take into account some deviations that allowed within the
2034          // specification."  Doesn't that mean RFC non-compliant?
2035          // http://support.microsoft.com/support/kb/articles/Q258/4/52.ASP
2036
2037          // all browsers need the application/octet-stream header for this
2038          header ("Content-Type: application/octet-stream; name=\"$filename\"");
2039
2040          // http://support.microsoft.com/support/kb/articles/Q182/3/15.asp
2041          // Do not have quotes around filename, but that applied to
2042          // "attachment"... does it apply to inline too?
2043          header ("Content-Disposition: attachment; filename=\"$filename\"");
2044
2045          if ($isIE && !$isIE6) {
2046              // This combination seems to work mostly.  IE 5.5 SP 1 has
2047              // known issues (see the Microsoft Knowledge Base)
2048
2049              // This works for most types, but doesn't work with Word files
2050              header ("Content-Type: application/download; name=\"$filename\"");
2051
2052              // These are spares, just in case.  :-)
2053              //header("Content-Type: $type0/$type1; name=\"$filename\"");
2054              //header("Content-Type: application/x-msdownload; name=\"$filename\"");
2055              //header("Content-Type: application/octet-stream; name=\"$filename\"");
2056          } else {
2057              // another application/octet-stream forces download for Netscape
2058              header ("Content-Type: application/octet-stream; name=\"$filename\"");
2059          }
2060      }
2061
2062      //send the content-length header if the calling function provides it
2063      if ($filesize > 0) {
2064          header("Content-Length: $filesize");
2065      }
2066
2067 }  // end fn SendDownloadHeaders
2068
2069 ?>