<?php

/*

Plugin Name: Upload/download frontend

Plugin URI: http://enano.homelinux.org/

Description: Provides the pages Special:UploadFile and Special:DownloadFile. UploadFile is used to upload files to the site, and DownloadFile fetches the file from the database, creates thumbnails if necessary, and sends the file to the user.

Author: Dan Fuhry

Version: 1.0

Author URI: http://enano.homelinux.org/

*/

/*

 * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between

 * Version 1.0 release candidate 2

 * Copyright (C) 2006-2007 Dan Fuhry

 * SpecialUpdownload.php - handles uploading and downloading of user-uploaded files - possibly the most rigorously security-enforcing script in all of Enano, although sessions.php comes in a close second

 *

 * This program is Free Software; you can redistribute and/or modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied

 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for details.

 */

global $db, $session, $paths, $template, $plugins; // Common objects

$plugins->attachHook('base_classes_initted', '

  global $paths;

    $paths->add_page(Array(

      \'name\'=>\'Upload file\',

      \'urlname\'=>\'UploadFile\',

      \'namespace\'=>\'Special\',

      \'special\'=>0,\'visible\'=>1,\'comments_on\'=>0,\'protected\'=>1,\'delvotes\'=>0,\'delvote_ips\'=>\'\',

      ));

    $paths->add_page(Array(

      \'name\'=>\'Download file\',

      \'urlname\'=>\'DownloadFile\',

      \'namespace\'=>\'Special\',

      \'special\'=>0,\'visible\'=>0,\'comments_on\'=>0,\'protected\'=>1,\'delvotes\'=>0,\'delvote_ips\'=>\'\',

      ));

    ');

function page_Special_UploadFile()

{

  global $db, $session, $paths, $template, $plugins; // Common objects

  global $mime_types;

  if(getConfig('enable_uploads')!='1') { die_friendly('Access denied', '<p>File uploads are disabled this website.</p>'); }

  if ( !$session->get_permissions('upload_files') )

  {

    die_friendly('Access denied', '<p>File uploads are disabled for your user account or group.<p>');

  }

  if(isset($_POST['doit']))

  {

    if(isset($_FILES['data']))

    {

      $file =& $_FILES['data'];

    }

    else

    {

      $file = false;

    }

    if(!is_array($file)) die_friendly('Upload failed', '<p>The server could not retrieve the array $_FILES[\'data\'].</p>');

    if($file['size'] == 0 || $file['size'] > (int)getConfig('max_file_size')) die_friendly('Upload failed', '<p>The file you uploaded is either too large or 0 bytes in length.</p>');

    /*

    $allowed_mime_types = Array(

        'text/plain',

        'image/png',

        'image/jpeg',

        'image/tiff',

        'image/gif',

        'text/html', // Safe because the file is stashed in the database

        'application/x-bzip2',

        'application/x-gzip',

        'text/x-c++'

      );

    if(function_exists('finfo_open') && $fi = finfo_open(FILEINFO_MIME, ENANO_ROOT.'/includes/magic')) // First try to use the fileinfo extension, this is the best way to determine the mimetype

    {

      if(!$fi) die_friendly('Upload failed', '<p>Enano was unable to determine the format of the uploaded file.</p><p>'.@finfo_file($fi, $file['tmp_name']).'</p>');

      $type = @finfo_file($fi, $file['tmp_name']);

      @finfo_close($fi);

    }

    elseif(function_exists('mime_content_type'))

      $type = mime_content_type($file['tmp_name']); // OK, no fileinfo function. Use a (usually) built-in PHP function

    elseif(isset($file['type']))

      $type = $file['type']; // LAST RESORT: use the mimetype the browser sent us, though this is likely to be spoofed

    else // DANG! Not even the browser told us. Bail out.

      die_friendly('Upload failed', '<p>Enano was unable to determine the format of the uploaded file.</p>');

    */

    $types = fetch_allowed_extensions();

    $ext = substr($file['name'], strrpos($file['name'], '.')+1, strlen($file['name']));

    if(!isset($types[$ext]) || ( isset($types[$ext]) && !$types[$ext] ) )

    {

      die_friendly('Upload failed', '<p>The file type ".'.$ext.'" is not allowed.</p>');

    }

    $type = $mime_types[$ext];

    //$type = explode(';', $type); $type = $type[0];

    //if(!in_array($type, $allowed_mime_types)) die_friendly('Upload failed', '<p>The file type "'.$type.'" is not allowed.</p>');

    if($_POST['rename'] != '')

    {

      $filename = $_POST['rename'];

    } else {

      $filename = $file['name'];

    }

    $bad_chars = Array(':', '\\', '/', '<', '>', '|', '*', '?', '"', '#', '+');

    foreach($bad_chars as $ch)

    {

      if(strstr($filename, $ch) || preg_match('/^([ ]+)$/is', $filename)) die_friendly('Upload failed', '<p>The filename contains invalid characters.</p>');

    }

    if(isset($paths->pages[$paths->nslist['File'].$filename]) && !isset($_POST['update'])) die_friendly('Upload failed', '<p>The file already exists. You can <a href="'.makeUrlNS('Special', 'UploadFile/'.$filename).'">upload a new version of this file</a>.</p>');

    elseif( isset($_POST['update']) && 

           (!isset($paths->pages[$paths->nslist['File'].$filename]) ||

             (isset($paths->pages[$paths->nslist['File'].$filename]) &&

               $paths->pages[$paths->nslist['File'].$filename]['protected']==1)

             )

           )

           die_friendly('Upload failed', '<p>Either the file does not exist (and therefore cannot be updated) or the file is protected.</p>');

    $utime = time();

    $filename = $db->escape($filename);

    $ext = substr($filename, strrpos($filename, '.'), strlen($filename));

    $flen = filesize($file['tmp_name']);

    $comments = $db->escape(RenderMan::strip_php($_POST['comments']));

    $chartag = sha1(microtime());

    $urln = str_replace(' ', '_', $filename);

    $key = md5($filename . '_' . file_get_contents($file['tmp_name']));

    $targetname = ENANO_ROOT . '/files/' . $key . '_' . $utime . $ext;

    if(!@move_uploaded_file($file['tmp_name'], $targetname))

    {

      die_friendly('Upload failed', '<p>Could not move uploaded file to the new location.</p>');

    }

    if(getConfig('file_history') != '1')

      if(!$db->sql_query('DELETE FROM  '.table_prefix.'files WHERE filename=\''.$filename.'\' LIMIT 1;')) $db->_die('The old file data could not be deleted.');

    if(!$db->sql_query('INSERT INTO '.table_prefix.'files(time_id,page_id,filename,size,mimetype,file_extension,file_key) VALUES('.$utime.', \''.$urln.'\', \''.$filename.'\', '.$flen.', \''.$type.'\', \''.$ext.'\', \''.$key.'\')')) $db->_die('The file data entry could not be inserted.');

    if(!isset($_POST['update']))

    {

      if(!$db->sql_query('INSERT INTO '.table_prefix.'logs(time_id,date_string,log_type,action,author,page_id,namespace) VALUES('.$utime.', \''.date('d M Y h:i a').'\', \'page\', \'create\', \''.$session->username.'\', \''.$filename.'\', \''.'File'.'\');')) $db->_die('The page log could not be updated.');

      if(!$db->sql_query('INSERT INTO '.table_prefix.'pages(name,urlname,namespace,protected,delvotes,delvote_ips) VALUES(\''.$filename.'\', \''.$urln.'\', \'File\', 0, 0, \'\')')) $db->_die('The page listing entry could not be inserted.');

      if(!$db->sql_query('INSERT INTO '.table_prefix.'page_text(page_id,namespace,page_text,char_tag) VALUES(\''.$urln.'\', \'File\', \''.$comments.'\', \''.$chartag.'\')')) $db->_die('The page text entry could not be inserted.');

    } else {

      if(!$db->sql_query('INSERT INTO '.table_prefix.'logs(time_id,date_string,log_type,action,author,page_id,namespace,edit_summary) VALUES('.$utime.', \''.date('d M Y h:i a').'\', \'page\', \'reupload\', \''.$session->username.'\', \''.$filename.'\', \''.'File'.'\', \''.$comments.'\');')) $db->_die('The page log could not be updated.');

    }

    die_friendly('Upload complete', '<p>Your file has been uploaded successfully. View the <a href="'.makeUrlNS('File', $filename).'">file\'s page</a>.</p>');

  } else {

    $template->header();

    $fn = $paths->getParam(0);

    if ( $fn && !$session->get_permissions('upload_new_version') )

    {

      die_friendly('Access denied', '<p>Uploading new versions of files has been disabled for your user account or group.<p>');

    }

    ?>

    <p>Using this form you can upload a file to the <?php echo getConfig('site_name'); ?> site.</p>

    <p>The maximum file size is <?php 

      // Get the max file size, and format it in a way that is user-friendly

      $fs = getConfig('max_file_size');

      echo $fs.' bytes';

      $fs = (int)$fs;

      if($fs >= 1048576)

      {

        $fs = round($fs / 1048576, 1);

        echo ' ('.$fs.' MB)';

      } elseif($fs >= 1024) {

        $fs = round($fs / 1024, 1);

        echo ' ('.$fs.' KB)';

      }

    ?>.</p>

    <form action="<?php echo makeUrl($paths->page); ?>" method="post" enctype="multipart/form-data">

      <table border="0" cellspacing="1" cellpadding="4">

        <tr><td>File:</td><td><input name="data" type="file" size="40" /></td></tr>

        <tr><td>Rename to:</td><td><input name="rename" type="text" size="40"<?php if($fn) echo ' value="'.$fn.'" readonly="readonly"'; ?> /></td></tr>

        <?php

        if(!$fn) echo '<tr><td>Comments:<br />(can be wiki-formatted)</td><td><textarea name="comments" rows="20" cols="60"></textarea></td></tr>';

        else echo '<tr><td>Reason for uploading the new version: </td><td><input name="comments" size="50" /></td></tr>';

        ?>

        <tr><td colspan="2" style="text-align: center">

          <?php

          if($fn)

            echo '<input type="hidden" name="update" value="true" />';

          ?>

          <input type="submit" name="doit" value="Upload file" />

        </td></tr>

      </table>

    </form>

    <?php

    $template->footer();

  }

}                                                                                                                                                          

function page_Special_DownloadFile()

{

  global $db, $session, $paths, $template, $plugins; // Common objects

  global $do_gzip;

  $filename = rawurldecode($paths->getParam(0));

  $timeid = $paths->getParam(1);

  if($timeid && preg_match('#^([0-9]+)$#', (string)$timeid)) $tid = ' AND time_id='.$timeid;

  else $tid = '';

  $filename = $db->escape($filename);

  $q = $db->sql_query('SELECT page_id,size,mimetype,time_id,file_extension,file_key FROM '.table_prefix.'files WHERE filename=\''.$filename.'\''.$tid.' ORDER BY time_id DESC;');

  if(!$q) $db->_die('The file data could not be selected.');

  if($db->numrows() < 1) { header('HTTP/1.1 404 Not Found'); die_friendly('File not found', '<p>The file "'.$filename.'" cannot be found.</p>'); }

  $row = $db->fetchrow();

  $db->free_result();

  // Check permissions

  $perms = $session->fetch_page_acl($row['page_id'], 'File');

  if ( !$perms->get_permissions('read') )

  {

    die_friendly('Access denied', '<p>Access to the specified file is denied.</p>');

  }

  $fname = ENANO_ROOT . '/files/' . $row['file_key'] . '_' . $row['time_id'] . $row['file_extension'];

  $data = file_get_contents($fname);

  if(isset($_GET['preview']) && getConfig('enable_imagemagick')=='1' && file_exists(getConfig('imagemagick_path')) && substr($row['mimetype'], 0, 6) == 'image/')

  {

    $nam = tempnam('/tmp', $filename);

    $h = @fopen($nam, 'w');

    if(!$h) die('Error opening '.$nam.' for writing');

    fwrite($h, $data);

    fclose($h);

    /* Make sure the request doesn't contain commandline injection - yow! */

    if(!isset($_GET['width' ]) || (isset($_GET['width'] ) && !preg_match('#^([0-9]+)$#', $_GET['width']  ))) $width  = '320'; else $width  = $_GET['width' ];

    if(!isset($_GET['height']) || (isset($_GET['height']) && !preg_match('#^([0-9]+)$#', $_GET['height'] ))) $height = '240'; else $height = $_GET['height'];

    $cache_filename=ENANO_ROOT.'/cache/'.$filename.'-'.$row['time_id'].'-'.$width.'x'.$height.$row['file_extension'];

    if(getConfig('cache_thumbs')=='1' && file_exists($cache_filename) && is_writable(ENANO_ROOT.'/cache')) {

      $data = file_get_contents($cache_filename);

    } elseif(getConfig('enable_imagemagick')=='1' && file_exists(getConfig('imagemagick_path'))) {

      // Use ImageMagick to convert the image

      //unlink($nam);

      error_reporting(E_ALL);

      $cmd = ''.getConfig('imagemagick_path').' "'.$nam.'" -resize "'.$width.'x'.$height.'>" "'.$nam.'.scaled'.$row['file_extension'].'"';

      system($cmd, $stat);

      if(!file_exists($nam.'.scaled'.$row['file_extension'])) die('Failed to call ImageMagick (return value '.$stat.'), command line was:<br />'.$cmd);

      $data = file_get_contents($nam.'.scaled'.$row['file_extension']);

      // Be stingy about it - better to re-generate the image hundreds of times than to fail completely

      if(getConfig('cache_thumbs')=='1' && !file_exists($cache_filename)) {

        // Write the generated thumbnail to the cache directory

        $h = @fopen($cache_filename, 'w');

        if(!$h) die('Error opening cache file "'.$cache_filename.'" for writing.');

        fwrite($h, $data);

        fclose($h);

      }

    }

    unlink($nam);

  }

  $len = strlen($data);

  header('Content-type: '.$row['mimetype']);

  if(isset($_GET['download'])) header('Content-disposition: attachment, filename="'.$filename.'";');

  header('Content-length: '.$len);

  header('Last-Modified: '.date('r', $row['time_id']));

  echo($data);

  //

  // Compress buffered output if required and send to browser

  //

  if ( $do_gzip )

  {

    //

    // Copied from phpBB, which was in turn borrowed from php.net

    //

    $gzip_contents = ob_get_contents();

    ob_end_clean();

    $gzip_size = strlen($gzip_contents);

    $gzip_crc = crc32($gzip_contents);

    $gzip_contents = gzcompress($gzip_contents, 9);

    $gzip_contents = substr($gzip_contents, 0, strlen($gzip_contents) - 4);

    header('Content-encoding: gzip');

    echo "\x1f\x8b\x08\x00\x00\x00\x00\x00";

    echo $gzip_contents;

    echo pack('V', $gzip_crc);

    echo pack('V', $gzip_size);

  }

  exit;

}

?>