<?php
// $Id: destinations.file.inc,v 1.3 2009-07-27 04:00:15 ronan Exp $


/**
 * @file
 * A destination type for saving locally to the server.
 */

/**
 * A destination type for saving locally to the server.
 *
 * @ingroup backup_migrate_destinations
 */

class backup_migrate_destination_files extends backup_migrate_destination {
  var $supported_ops = array('scheduled backup', 'manual backup', 'restore', 'list files', 'configure', 'delete');

  function type_name() {
    return t("Server Directory");
  }

  /**
   * File save destination callback.
   */
  function save_file($file, $settings) {
    if ($dir = $this->get_location()) {
      if ($this->check_dir($dir)) {
        $filepath = rtrim($dir, "/") ."/". $file->filename();
        rename($file->filepath(), $filepath);

        // chmod, chown and chgrp the file if needed.
        if ($chmod = $this->settings('chmod')) {
          if (!@chmod($filepath, octdec($chmod))) {
            _backup_migrate_message('Unable to set the file mode for: @file', array('@file' => $filepath), 'error');
          }
        }
        if ($chgrp = $this->settings('chgrp')) {
          if (!@chgrp($filepath, $chgrp)) {
            _backup_migrate_message('Unable to set the file group for: @file', array('@file' => $filepath), 'error');
          }
        }
        return $file;
      }
    }
  }

  /**
   * Determine if we can read the given file.
   */
  function can_read_file($file_id) {
    return $this->op('restore') && is_readable($this->get_filepath($file_id));
  }

  /**
   * File load destination callback.
   */
  function load_file($file_id) {
    $filepath = $this->get_filepath($file_id);
    if (file_exists($filepath)) {
      backup_migrate_include('files');
      return new backup_file(array('filepath' => $filepath));
    }
  }

  /**
   * File list destination callback.
   */
  function list_files() {
    $files = array();
    if ($dir = $this->get_location()) {
      if ($handle = @opendir($dir)) {
        backup_migrate_include('files');
        while (FALSE !== ($file = readdir($handle))) {
          $filepath = $dir ."/". $file;
          $files[$file] = new backup_file(array('filepath' => $filepath));
        }
      }
    }
    return $files;
  }

  /**
   * File delete destination callback.
   */
  function delete_file($file_id) {
    $filepath = $this->get_filepath($file_id);
    file_delete($filepath);
  }

  /**
   * Get the filepath from the given file id.
   */
  function get_filepath($file_id) {
    $filepath = rtrim($this->get_location(), '/') .'/'. $file_id;
    return $filepath;
  }

  /**
   * Get the form for the settings for the files destination.
   */
  /**
   * Get the edit form for the item.
   */
  function edit_form() {
    $form = parent::edit_form();
    $form['location'] = array(
      "#type" => "textfield",
      "#title" => t("Directory path"),
      "#default_value" => $this->get_location(),
      "#required" => TRUE,
      "#description" => t('Enter the path to the directory to save the backups to. Use a relative path to pick a path relative to your Drupal root directory. The web server must be able to write to this path.'),
    );
    $form['settings'] = array(
      '#type' => 'fieldset',
      '#title' => t('Advanced Settings'),
      '#tree' => TRUE,
      '#collapsible' => TRUE,
      '#collapsed' => TRUE,
    );
    if (function_exists('chmod')) {
      $form['settings']['chmod'] = array(
        '#type' => 'textfield',
        '#title' => t('Change file mode (chmod)'),
        '#size' => 5,
        '#default_value' => $this->settings('chmod'),
        '#description' => t('If you enter a value here, backup files will be chmoded with the mode you specify. Specify the mode in octal form (e.g. 644 or 0644) or leave blank to disable this feature.'),
      );
    }
    if (function_exists('chgrp')) {
      $form['settings']['chgrp'] = array(
        '#type' => 'textfield',
        '#title' => t('Change file group (chgrp)'),
        '#size' => 5,
        '#default_value' => $this->settings('chgrp'),
        '#description' => t('If you enter a value here, backup files will be chgrped to the group you specify. Leave blank to disable this feature.'),
      );
    }
    return $form;
  }
 
  /**
   * Validate the form for the settings for the files destination.
   */
  function edit_form_validate($form, &$form_state) {
    $values = $form_state['values'];
    if (isset($values['settings']['chmod']) && !empty($values['settings']['chmod']) && !preg_match('/0?[0-7]{3}/', $values['settings']['chmod'])) {
      form_set_error('chmod', t('You must enter a valid chmod octal value (e.g. 644 or 0644) in the change mode field, or leave it blank.'));
    }
    parent::edit_form_validate($form, $form_state);
  }

  /**
   * Submit the form for the settings for the files destination.
   */
  function edit_form_submit($form, &$form_state) {
    // Add a 0 to the start of a 3 digit file mode to make it proper PHP encoded octal.
    if (strlen($form_state['values']['settings']['chmod']) == 3) {
      $form_state['values']['settings']['chmod'] = '0' . $form_state['values']['settings']['chmod'];
    }
    parent::edit_form_submit($form, $form_state);
  }

  /**
   * Prepare the destination directory for the backups.
   */
  function check_dir($directory) {
    $out = TRUE;
    $dirs = array();
    foreach (explode('/', $directory) as $dir) {
      $dirs[] = $dir;
      $path = implode($dirs, '/');
      if ($path && !is_dir(realpath($path)) && !file_check_directory($path, FILE_CREATE_DIRECTORY)) {
        $out = FALSE;
      }
    }

    if (!$out || !file_check_directory($directory)) {
      // Unable to create destination directory.
      _backup_migrate_message("Unable to create or write to the save directory '%directory'. Please check the file permissions that directory and try again.", array('%directory' => $directory), "error");
      return FALSE;
    }

    // If the destination directory is within the webroot, then secure it as best we can.
    if ($this->dir_in_webroot($directory)) {
      $directory = $this->check_web_dir($directory);
    }

    return $directory;
  }

  /**
   * Check that a web accessible directory has been properly secured, othewise attempt to secure it.
   */
  function check_web_dir($directory) {
    if (!is_file($directory .'/checked.txt')) {
      // Check for a htaccess file which adequately protects the backup files.
      $htaccess_lines = "order allow,deny\ndeny from all\n";
      if (!is_file($directory .'/.htaccess') || strpos(file_get_contents($directory .'/.htaccess'), $htaccess_lines) === FALSE) {
        // Attempt to protect the backup files from public access using htaccess.
        if (($fp = @fopen($directory .'/.htaccess', 'w')) && @fputs($fp, $htaccess_lines)) {
          fclose($fp);
          chmod($directory .'/.htaccess', 0664);
        }
        // Unable to create htaccess... warn the user.
        else {
          $message = "Security warning: Couldn't modify .htaccess file. Please create a .htaccess file in your %directory directory which contains the following lines: <code>!htaccess</code> or add them to the existing .htaccess file";
          $replace = array('%directory' => $directory, '!htaccess' => '<br />'. nl2br(check_plain($htaccess_lines)));
          drupal_set_message(t($message, $replace), "error");
          watchdog('security', t($message, $replace), WATCHDOG_ERROR);
          return FALSE;
        }
      }
  
      // Check the user agent to make sure we're not responding to a request from drupal itself.
      // That should prevent infinite loops which could be caused by poormanscron in some circumstances.
      if (strpos($_SERVER['HTTP_USER_AGENT'], 'Drupal') !== FALSE) {
        return FALSE;
      }
  
      // Check to see if the destination is publicly accessible
      $test_contents = "this file should not be publicly accesible";
      // Create the the text.txt file if it's not already there.
      if (!is_file($directory .'/test.txt') || file_get_contents($directory .'/test.txt') != $test_contents) {
        if ($fp = fopen($directory .'/test.txt', 'w')) {
          @fputs($fp, $test_contents);
          fclose($fp);
        }
        else {
          $message = t("Security notice: Backup and Migrate was unable to write a test text file to the destination directory %directory, and is therefore unable to check the security of the backup destination. Backups to the server will be disabled until the destination becomes writable and secure.", array('%directory' => $directory));
          drupal_set_message($message, "error");
          return FALSE;
        }
      }
  
      // Attempt to read the test file via http. This may fail for other reasons,
      // so it's not a bullet-proof check.
      $path = trim(drupal_substr($directory .'/test.txt', drupal_strlen(file_directory_path())), '\\/');
      if ($this->test_file_readable_remotely($path, $test_contents)) {
        $message = t("Security notice: Backup and Migrate will not save backup files to the server because the destination directory is publicly accessible. If you want to save files to the server, please secure the '%directory' directory", array('%directory' => $directory));
        drupal_set_message($message, "error");
        return FALSE;
      }

      // Directory was checked and passed, create the 'checked.txt' file so we don't have to check again.
      $checked_contents = t("This file indicates that this directory has been checked for public access. Do not remove this file unless you change your server settings or file permissions.");
      // Create the the checked.txt file.
      if ($fp = fopen($directory .'/checked.txt', 'w')) {
        @fputs($fp, $checked_contents);
        fclose($fp);
      }
    }
    return $directory;
  }

  /**
   * Check if the given directory is within the webroot and is therefore web accessible.
   */
  function dir_in_webroot($directory) {
    if (strpos(realpath($directory), realpath($_SERVER['DOCUMENT_ROOT'])) !== FALSE) {
      return TRUE;
    }
    return FALSE;
  }

  /**
   * Check if a file can be read remotely via http.
   */
  function test_file_readable_remotely($path, $contents) {
    $url = $GLOBALS['base_url'] .'/'. file_directory_path() .'/'. str_replace('\\', '/', $path);
    $result = drupal_http_request($url);
    if (strpos($result->data, $contents) !== FALSE) {
      return TRUE;
    }
    return FALSE;
  }
}

/**
 * The built in default files directories. This is more or less a legacy holdover from v1.
 * But they serve a purpose as a meaningful default.
 */
class backup_migrate_destination_files_builtin extends backup_migrate_destination_files {
  function __construct($params = array()) {
    $params['location'] = $this->check_destination_dir($params['mode']);
    $params['destination_id'] = $params['mode'];
    parent::__construct($params);
  }

  /**
   * Check the default backup desitantion directory. Included as legacy support.
   */
  function check_destination_dir($mode = "manual") {
    return $this->check_dir($this->get_save_path($mode));
  }

  /**
   * Return the path on the server to save the dump files.
   */
  function get_save_path($mode = "") {
    $dir = file_directory_path() ."/backup_migrate";
    if ($mode) {
      $dir .= $mode == "manual" ? "/manual" : "/scheduled";
    }
    return $dir;
  }
}

/**
 * The manual files directory.
 */
class backup_migrate_destination_files_manual extends backup_migrate_destination_files {
  var $supported_ops = array('manual backup', 'restore', 'list files', 'configure', 'delete');
  function __construct($params = array()) {
    $dir = file_directory_path() .'/backup_migrate/manual';
    parent::__construct($params + array('location' => $dir, 'name' => t('Manual Backups Directory')));
  }
}

/**
 * The scheduled files directory.
 */
class backup_migrate_destination_files_scheduled extends backup_migrate_destination_files {
  var $supported_ops = array('scheduled backup', 'restore', 'list files', 'configure', 'delete');
  function __construct($params = array()) {
    $dir = file_directory_path() .'/backup_migrate/scheduled';
    parent::__construct($params + array('location' => $dir, 'name' => t('Scheduled Backups Directory')));
  }
}