roundcubemail/program/include/rcmail.php

<?php

/*
 +-----------------------------------------------------------------------+
 | program/include/rcmail.php                                            |
 |                                                                       |
 | This file is part of the Roundcube Webmail client                     |
 | Copyright (C) 2008-2012, The Roundcube Dev Team                       |
 | Copyright (C) 2011-2012, Kolab Systems AG                             |
 |                                                                       |
 | Licensed under the GNU General Public License version 3 or            |
 | any later version with exceptions for skins & plugins.                |
 | See the README file for a full license statement.                     |
 |                                                                       |
 | PURPOSE:                                                              |
 |   Application class providing core functions and holding              |
 |   instances of all 'global' objects like db- and imap-connections     |
 +-----------------------------------------------------------------------+
 | Author: Thomas Bruederli <roundcube@gmail.com>                        |
 +-----------------------------------------------------------------------+

 $Id$

*/


/**
 * Application class of Roundcube Webmail
 * implemented as singleton
 *
 * @package Core
 */
class rcmail extends rcube
{
  /**
   * Main tasks.
   *
   * @var array
   */
  static public $main_tasks = array('mail','settings','addressbook','login','logout','utils','dummy');

  /**
   * Current task.
   *
   * @var string
   */
  public $task;

  /**
   * Current action.
   *
   * @var string
   */
  public $action = '';
  public $comm_path = './';

  private $address_books = array();
  private $action_map = array();


  /**
   * This implements the 'singleton' design pattern
   *
   * @return rcmail The one and only instance
   */
  static function get_instance()
  {
    if (!self::$instance || !is_a(self::$instance, 'rcmail')) {
      self::$instance = new rcmail();
      self::$instance->startup();  // init AFTER object was linked with self::$instance
    }

    return self::$instance;
  }


  /**
   * Initial startup function
   * to register session, create database and imap connections
   */
  protected function startup()
  {
    $this->init(self::INIT_WITH_DB | self::INIT_WITH_PLUGINS);

    // start session
    $this->session_init();

    // create user object
    $this->set_user(new rcube_user($_SESSION['user_id']));

    // configure session (after user config merge!)
    $this->session_configure();

    // set task and action properties
    $this->set_task(rcube_ui::get_input_value('_task', rcube_ui::INPUT_GPC));
    $this->action = asciiwords(rcube_ui::get_input_value('_action', rcube_ui::INPUT_GPC));

    // reset some session parameters when changing task
    if ($this->task != 'utils') {
      if ($this->session && $_SESSION['task'] != $this->task)
        $this->session->remove('page');
      // set current task to session
      $_SESSION['task'] = $this->task;
    }

    // init output class
    if (!empty($_REQUEST['_remote']))
      $GLOBALS['OUTPUT'] = $this->json_init();
    else
      $GLOBALS['OUTPUT'] = $this->load_gui(!empty($_REQUEST['_framed']));

    // load plugins
    $this->plugins->init($this, $this->task);
    $this->plugins->load_plugins((array)$this->config->get('plugins', array()), array('filesystem_attachments', 'jqueryui'));
  }


  /**
   * Setter for application task
   *
   * @param string Task to set
   */
  public function set_task($task)
  {
    $task = asciiwords($task);

    if ($this->user && $this->user->ID)
      $task = !$task ? 'mail' : $task;
    else
      $task = 'login';

    $this->task = $task;
    $this->comm_path = $this->url(array('task' => $this->task));

    if ($this->output)
      $this->output->set_env('task', $this->task);
  }


  /**
   * Setter for system user object
   *
   * @param rcube_user Current user instance
   */
  public function set_user($user)
  {
    if (is_object($user)) {
      $this->user = $user;

      // overwrite config with user preferences
      $this->config->set_user_prefs((array)$this->user->get_prefs());
    }

    $_SESSION['language'] = $this->user->language = $this->language_prop($this->config->get('language', $_SESSION['language']));

    // set localization
    setlocale(LC_ALL, $_SESSION['language'] . '.utf8', 'en_US.utf8');

    // workaround for http://bugs.php.net/bug.php?id=18556
    if (in_array($_SESSION['language'], array('tr_TR', 'ku', 'az_AZ')))
      setlocale(LC_CTYPE, 'en_US' . '.utf8');
  }


  /**
   * Return instance of the internal address book class
   *
   * @param string  Address book identifier
   * @param boolean True if the address book needs to be writeable
   *
   * @return rcube_contacts Address book object
   */
  public function get_address_book($id, $writeable = false)
  {
    $contacts    = null;
    $ldap_config = (array)$this->config->get('ldap_public');
    $abook_type  = strtolower($this->config->get('address_book_type'));

    // 'sql' is the alias for '0' used by autocomplete
    if ($id == 'sql')
        $id = '0';

    // use existing instance
    if (isset($this->address_books[$id]) && is_object($this->address_books[$id])
      && is_a($this->address_books[$id], 'rcube_addressbook')
      && (!$writeable || !$this->address_books[$id]->readonly)
    ) {
      $contacts = $this->address_books[$id];
    }
    else if ($id && $ldap_config[$id]) {
      $contacts = new rcube_ldap($ldap_config[$id], $this->config->get('ldap_debug'), $this->config->mail_domain($_SESSION['storage_host']));
    }
    else if ($id === '0') {
      $contacts = new rcube_contacts($this->db, $this->get_user_id());
    }
    else {
      $plugin = $this->plugins->exec_hook('addressbook_get', array('id' => $id, 'writeable' => $writeable));

      // plugin returned instance of a rcube_addressbook
      if ($plugin['instance'] instanceof rcube_addressbook) {
        $contacts = $plugin['instance'];
      }
      // get first source from the list
      else if (!$id) {
        $source = reset($this->get_address_sources($writeable));
        if (!empty($source)) {
          $contacts = $this->get_address_book($source['id']);
          if ($contacts)
            $id = $source['id'];
        }
      }
    }

    if (!$contacts) {
      self::raise_error(array(
        'code' => 700, 'type' => 'php',
        'file' => __FILE__, 'line' => __LINE__,
        'message' => "Addressbook source ($id) not found!"),
        true, true);
    }

    // set configured sort order
    if ($sort_col = $this->config->get('addressbook_sort_col'))
        $contacts->set_sort_order($sort_col);

    // add to the 'books' array for shutdown function
    $this->address_books[$id] = $contacts;

    return $contacts;
  }


  /**
   * Return address books list
   *
   * @param boolean True if the address book needs to be writeable
   *
   * @return array  Address books array
   */
  public function get_address_sources($writeable = false)
  {
    $abook_type = strtolower($this->config->get('address_book_type'));
    $ldap_config = $this->config->get('ldap_public');
    $autocomplete = (array) $this->config->get('autocomplete_addressbooks');
    $list = array();

    // We are using the DB address book
    if ($abook_type != 'ldap') {
      if (!isset($this->address_books['0']))
        $this->address_books['0'] = new rcube_contacts($this->db, $this->get_user_id());
      $list['0'] = array(
        'id'       => '0',
        'name'     => $this->gettext('personaladrbook'),
        'groups'   => $this->address_books['0']->groups,
        'readonly' => $this->address_books['0']->readonly,
        'autocomplete' => in_array('sql', $autocomplete),
        'undelete' => $this->address_books['0']->undelete && $this->config->get('undo_timeout'),
      );
    }

    if ($ldap_config) {
      $ldap_config = (array) $ldap_config;
      foreach ($ldap_config as $id => $prop) {
        // handle misconfiguration
        if (empty($prop) || !is_array($prop)) {
          continue;
        }
        $list[$id] = array(
          'id'       => $id,
          'name'     => $prop['name'],
          'groups'   => is_array($prop['groups']),
          'readonly' => !$prop['writable'],
          'hidden'   => $prop['hidden'],
          'autocomplete' => in_array($id, $autocomplete)
        );
      }
    }

    $plugin = $this->plugins->exec_hook('addressbooks_list', array('sources' => $list));
    $list = $plugin['sources'];

    foreach ($list as $idx => $item) {
      // register source for shutdown function
      if (!is_object($this->address_books[$item['id']]))
        $this->address_books[$item['id']] = $item;
      // remove from list if not writeable as requested
      if ($writeable && $item['readonly'])
          unset($list[$idx]);
    }

    return $list;
  }


  /**
   * Init output object for GUI and add common scripts.
   * This will instantiate a rcmail_template object and set
   * environment vars according to the current session and configuration
   *
   * @param boolean True if this request is loaded in a (i)frame
   * @return rcube_output_html Reference to HTML output object
   */
  public function load_gui($framed = false)
  {
    // init output page
    if (!($this->output instanceof rcube_output_html))
      $this->output = new rcube_output_html($this->task, $framed);

    // set keep-alive/check-recent interval
    if ($this->session && ($keep_alive = $this->session->get_keep_alive())) {
      $this->output->set_env('keep_alive', $keep_alive);
    }

    if ($framed) {
      $this->comm_path .= '&_framed=1';
      $this->output->set_env('framed', true);
    }

    $this->output->set_env('task', $this->task);
    $this->output->set_env('action', $this->action);
    $this->output->set_env('comm_path', $this->comm_path);
    $this->output->set_charset(RCMAIL_CHARSET);

    // add some basic labels to client
    $this->output->add_label('loading', 'servererror');

    return $this->output;
  }


  /**
   * Create an output object for JSON responses
   *
   * @return rcube_output_json Reference to JSON output object
   */
  public function json_init()
  {
    if (!($this->output instanceof rcube_output_json))
      $this->output = new rcube_output_json($this->task);

    return $this->output;
  }


  /**
   * Create session object and start the session.
   */
  public function session_init()
  {
    // session started (Installer?)
    if (session_id())
      return;

    $sess_name   = $this->config->get('session_name');
    $sess_domain = $this->config->get('session_domain');
    $lifetime    = $this->config->get('session_lifetime', 0) * 60;

    // set session domain
    if ($sess_domain) {
      ini_set('session.cookie_domain', $sess_domain);
    }
    // set session garbage collecting time according to session_lifetime
    if ($lifetime) {
      ini_set('session.gc_maxlifetime', $lifetime * 2);
    }

    ini_set('session.cookie_secure', rcube_ui::https_check());
    ini_set('session.name', $sess_name ? $sess_name : 'roundcube_sessid');
    ini_set('session.use_cookies', 1);
    ini_set('session.use_only_cookies', 1);
    ini_set('session.serialize_handler', 'php');

    // use database for storing session data
    $this->session = new rcube_session($this->get_dbh(), $this->config);

    $this->session->register_gc_handler(array($this, 'temp_gc'));
    $this->session->register_gc_handler(array($this, 'cache_gc'));

    // start PHP session (if not in CLI mode)
    if ($_SERVER['REMOTE_ADDR'])
      session_start();

    // set initial session vars
    if (!$_SESSION['user_id'])
      $_SESSION['temp'] = true;

    // restore skin selection after logout
    if ($_SESSION['temp'] && !empty($_SESSION['skin']))
      $this->config->set('skin', $_SESSION['skin']);
  }


  /**
   * Configure session object internals
   */
  public function session_configure()
  {
    if (!$this->session)
      return;

    $lifetime = $this->config->get('session_lifetime', 0) * 60;

    // set keep-alive/check-recent interval
    if ($keep_alive = $this->config->get('keep_alive')) {
      // be sure that it's less than session lifetime
      if ($lifetime)
        $keep_alive = min($keep_alive, $lifetime - 30);
      $keep_alive = max(60, $keep_alive);
      $this->session->set_keep_alive($keep_alive);
    }

    $this->session->set_secret($this->config->get('des_key') . $_SERVER['HTTP_USER_AGENT']);
    $this->session->set_ip_check($this->config->get('ip_check'));
  }


  /**
   * Perfom login to the mail server and to the webmail service.
   * This will also create a new user entry if auto_create_user is configured.
   *
   * @param string Mail storage (IMAP) user name
   * @param string Mail storage (IMAP) password
   * @param string Mail storage (IMAP) host
   *
   * @return boolean True on success, False on failure
   */
  function login($username, $pass, $host=NULL)
  {
    if (empty($username)) {
      return false;
    }

    $config = $this->config->all();

    if (!$host)
      $host = $config['default_host'];

    // Validate that selected host is in the list of configured hosts
    if (is_array($config['default_host'])) {
      $allowed = false;
      foreach ($config['default_host'] as $key => $host_allowed) {
        if (!is_numeric($key))
          $host_allowed = $key;
        if ($host == $host_allowed) {
          $allowed = true;
          break;
        }
      }
      if (!$allowed)
        return false;
      }
    else if (!empty($config['default_host']) && $host != self::parse_host($config['default_host']))
      return false;

    // parse $host URL
    $a_host = parse_url($host);
    if ($a_host['host']) {
      $host = $a_host['host'];
      $ssl = (isset($a_host['scheme']) && in_array($a_host['scheme'], array('ssl','imaps','tls'))) ? $a_host['scheme'] : null;
      if (!empty($a_host['port']))
        $port = $a_host['port'];
      else if ($ssl && $ssl != 'tls' && (!$config['default_port'] || $config['default_port'] == 143))
        $port = 993;
    }

    if (!$port) {
        $port = $config['default_port'];
    }

    /* Modify username with domain if required
       Inspired by Marco <P0L0_notspam_binware.org>
    */
    // Check if we need to add domain
    if (!empty($config['username_domain']) && strpos($username, '@') === false) {
      if (is_array($config['username_domain']) && isset($config['username_domain'][$host]))
        $username .= '@'.self::parse_host($config['username_domain'][$host], $host);
      else if (is_string($config['username_domain']))
        $username .= '@'.self::parse_host($config['username_domain'], $host);
    }

    // Convert username to lowercase. If storage backend
    // is case-insensitive we need to store always the same username (#1487113)
    if ($config['login_lc']) {
      $username = mb_strtolower($username);
    }

    // try to resolve email address from virtuser table
    if (strpos($username, '@') && ($virtuser = rcube_user::email2user($username))) {
      $username = $virtuser;
    }

    // Here we need IDNA ASCII
    // Only rcube_contacts class is using domain names in Unicode
    $host = rcube_idn_to_ascii($host);
    if (strpos($username, '@')) {
      // lowercase domain name
      list($local, $domain) = explode('@', $username);
      $username = $local . '@' . mb_strtolower($domain);
      $username = rcube_idn_to_ascii($username);
    }

    // user already registered -> overwrite username
    if ($user = rcube_user::query($username, $host))
      $username = $user->data['username'];

    if (!$this->storage)
      $this->storage_init();

    // try to log in
    if (!($login = $this->storage->connect($host, $username, $pass, $port, $ssl))) {
      // try with lowercase
      $username_lc = mb_strtolower($username);
      if ($username_lc != $username) {
        // try to find user record again -> overwrite username
        if (!$user && ($user = rcube_user::query($username_lc, $host)))
          $username_lc = $user->data['username'];

        if ($login = $this->storage->connect($host, $username_lc, $pass, $port, $ssl))
          $username = $username_lc;
      }
    }

    // exit if login failed
    if (!$login) {
      return false;
    }

    // user already registered -> update user's record
    if (is_object($user)) {
      // update last login timestamp
      $user->touch();
    }
    // create new system user
    else if ($config['auto_create_user']) {
      if ($created = rcube_user::create($username, $host)) {
        $user = $created;
      }
      else {
        self::raise_error(array(
          'code' => 620, 'type' => 'php',
          'file' => __FILE__, 'line' => __LINE__,
          'message' => "Failed to create a user record. Maybe aborted by a plugin?"
          ), true, false);
      }
    }
    else {
      self::raise_error(array(
        'code' => 621, 'type' => 'php',
        'file' => __FILE__, 'line' => __LINE__,
        'message' => "Access denied for new user $username. 'auto_create_user' is disabled"
        ), true, false);
    }

    // login succeeded
    if (is_object($user) && $user->ID) {
      // Configure environment
      $this->set_user($user);
      $this->set_storage_prop();
      $this->session_configure();

      // fix some old settings according to namespace prefix
      $this->fix_namespace_settings($user);

      // create default folders on first login
      if ($config['create_default_folders'] && (!empty($created) || empty($user->data['last_login']))) {
        $this->storage->create_default_folders();
      }

      // set session vars
      $_SESSION['user_id']      = $user->ID;
      $_SESSION['username']     = $user->data['username'];
      $_SESSION['storage_host'] = $host;
      $_SESSION['storage_port'] = $port;
      $_SESSION['storage_ssl']  = $ssl;
      $_SESSION['password']     = $this->encrypt($pass);
      $_SESSION['login_time']   = mktime();

      if (isset($_REQUEST['_timezone']) && $_REQUEST['_timezone'] != '_default_')
        $_SESSION['timezone'] = floatval($_REQUEST['_timezone']);
      if (isset($_REQUEST['_dstactive']) && $_REQUEST['_dstactive'] != '_default_')
        $_SESSION['dst_active'] = intval($_REQUEST['_dstactive']);

      // force reloading complete list of subscribed mailboxes
      $this->storage->clear_cache('mailboxes', true);

      return true;
    }

    return false;
  }


  /**
   * Auto-select IMAP host based on the posted login information
   *
   * @return string Selected IMAP host
   */
  public function autoselect_host()
  {
    $default_host = $this->config->get('default_host');
    $host = null;

    if (is_array($default_host)) {
      $post_host = rcube_ui::get_input_value('_host', rcube_ui::INPUT_POST);

      // direct match in default_host array
      if ($default_host[$post_host] || in_array($post_host, array_values($default_host))) {
        $host = $post_host;
      }

      // try to select host by mail domain
      list($user, $domain) = explode('@', rcube_ui::get_input_value('_user', rcube_ui::INPUT_POST));
      if (!empty($domain)) {
        foreach ($default_host as $storage_host => $mail_domains) {
          if (is_array($mail_domains) && in_array_nocase($domain, $mail_domains)) {
            $host = $storage_host;
            break;
          }
          else if (stripos($storage_host, $domain) !== false || stripos(strval($mail_domains), $domain) !== false) {
            $host = is_numeric($storage_host) ? $mail_domains : $storage_host;
            break;
          }
        }
      }

      // take the first entry if $host is still not set
      if (empty($host)) {
        list($key, $val) = each($default_host);
        $host = is_numeric($key) ? $val : $key;
      }
    }
    else if (empty($default_host)) {
      $host = rcube_ui::get_input_value('_host', rcube_ui::INPUT_POST);
    }
    else
      $host = self::parse_host($default_host);

    return $host;
  }


  /**
   * Destroy session data and remove cookie
   */
  public function kill_session()
  {
    $this->plugins->exec_hook('session_destroy');

    $this->session->kill();
    $_SESSION = array('language' => $this->user->language, 'temp' => true, 'skin' => $this->config->get('skin'));
    $this->user->reset();
  }


  /**
   * Do server side actions on logout
   */
  public function logout_actions()
  {
    $config = $this->config->all();

    // on logout action we're not connected to imap server
    if (($config['logout_purge'] && !empty($config['trash_mbox'])) || $config['logout_expunge']) {
      if (!$this->session->check_auth())
        return;

      $this->storage_connect();
    }

    if ($config['logout_purge'] && !empty($config['trash_mbox'])) {
      $this->storage->clear_folder($config['trash_mbox']);
    }

    if ($config['logout_expunge']) {
      $this->storage->expunge_folder('INBOX');
    }

    // Try to save unsaved user preferences
    if (!empty($_SESSION['preferences'])) {
      $this->user->save_prefs(unserialize($_SESSION['preferences']));
    }
  }


  /**
   * Garbage collector for cache entries.
   * Set flag to expunge caches on shutdown
   */
  function cache_gc()
  {
    // because this gc function is called before storage is initialized,
    // we just set a flag to expunge storage cache on shutdown.
    $this->expunge_cache = true;
  }


  /**
   * Generate a unique token to be used in a form request
   *
   * @return string The request token
   */
  public function get_request_token()
  {
    $sess_id = $_COOKIE[ini_get('session.name')];
    if (!$sess_id) $sess_id = session_id();
    $plugin = $this->plugins->exec_hook('request_token', array('value' => md5('RT' . $this->get_user_id() . $this->config->get('des_key') . $sess_id)));
    return $plugin['value'];
  }


  /**
   * Check if the current request contains a valid token
   *
   * @param int Request method
   * @return boolean True if request token is valid false if not
   */
  public function check_request($mode = rcube_ui::INPUT_POST)
  {
    $token = rcube_ui::get_input_value('_token', $mode);
    $sess_id = $_COOKIE[ini_get('session.name')];
    return !empty($sess_id) && $token == $this->get_request_token();
  }


  /**
   * Create unique authorization hash
   *
   * @param string Session ID
   * @param int Timestamp
   * @return string The generated auth hash
   */
  private function get_auth_hash($sess_id, $ts)
  {
    $auth_string = sprintf('rcmail*sess%sR%s*Chk:%s;%s',
      $sess_id,
      $ts,
      $this->config->get('ip_check') ? $_SERVER['REMOTE_ADDR'] : '***.***.***.***',
      $_SERVER['HTTP_USER_AGENT']);

    if (function_exists('sha1'))
      return sha1($auth_string);
    else
      return md5($auth_string);
  }


  /**
   * Build a valid URL to this instance of Roundcube
   *
   * @param mixed Either a string with the action or url parameters as key-value pairs
   * @return string Valid application URL
   */
  public function url($p)
  {
    if (!is_array($p))
      $p = array('_action' => @func_get_arg(0));

    $task = $p['_task'] ? $p['_task'] : ($p['task'] ? $p['task'] : $this->task);
    $p['_task'] = $task;
    unset($p['task']);

    $url = './';
    $delm = '?';
    foreach (array_reverse($p) as $key => $val) {
      if ($val !== '' && $val !== null) {
        $par = $key[0] == '_' ? $key : '_'.$key;
        $url .= $delm.urlencode($par).'='.urlencode($val);
        $delm = '&';
      }
    }
    return $url;
  }


  /**
   * Function to be executed in script shutdown
   */
  public function shutdown()
  {
    parent::shutdown();

    foreach ($this->address_books as $book) {
      if (is_object($book) && is_a($book, 'rcube_addressbook'))
        $book->close();
    }

    // before closing the database connection, write session data
    if ($_SERVER['REMOTE_ADDR'] && is_object($this->session)) {
      session_write_close();
    }

    // write performance stats to logs/console
    if ($this->config->get('devel_mode')) {
      if (function_exists('memory_get_usage'))
        $mem = rcube_ui::show_bytes(memory_get_usage());
      if (function_exists('memory_get_peak_usage'))
        $mem .= '/'.rcube_ui::show_bytes(memory_get_peak_usage());

      $log = $this->task . ($this->action ? '/'.$this->action : '') . ($mem ? " [$mem]" : '');
      if (defined('RCMAIL_START'))
        self::print_timer(RCMAIL_START, $log);
      else
        self::console($log);
    }
  }

  /**
   * Helper method to set a cookie with the current path and host settings
   *
   * @param string Cookie name
   * @param string Cookie value
   * @param string Expiration time
   */
  public static function setcookie($name, $value, $exp = 0)
  {
    if (headers_sent())
      return;

    $cookie = session_get_cookie_params();

    setcookie($name, $value, $exp, $cookie['path'], $cookie['domain'],
      rcube_ui::https_check(), true);
  }

  /**
   * Registers action aliases for current task
   *
   * @param array $map Alias-to-filename hash array
   */
  public function register_action_map($map)
  {
    if (is_array($map)) {
      foreach ($map as $idx => $val) {
        $this->action_map[$idx] = $val;
      }
    }
  }

  /**
   * Returns current action filename
   *
   * @param array $map Alias-to-filename hash array
   */
  public function get_action_file()
  {
    if (!empty($this->action_map[$this->action])) {
      return $this->action_map[$this->action];
    }

    return strtr($this->action, '-', '_') . '.inc';
  }

  /**
   * Fixes some user preferences according to namespace handling change.
   * Old Roundcube versions were using folder names with removed namespace prefix.
   * Now we need to add the prefix on servers where personal namespace has prefix.
   *
   * @param rcube_user $user User object
   */
  private function fix_namespace_settings($user)
  {
    $prefix     = $this->storage->get_namespace('prefix');
    $prefix_len = strlen($prefix);

    if (!$prefix_len)
      return;

    $prefs = $this->config->all();
    if (!empty($prefs['namespace_fixed']))
      return;

    // Build namespace prefix regexp
    $ns     = $this->storage->get_namespace();
    $regexp = array();

    foreach ($ns as $entry) {
      if (!empty($entry)) {
        foreach ($entry as $item) {
          if (strlen($item[0])) {
            $regexp[] = preg_quote($item[0], '/');
          }
        }
      }
    }
    $regexp = '/^('. implode('|', $regexp).')/';

    // Fix preferences
    $opts = array('drafts_mbox', 'junk_mbox', 'sent_mbox', 'trash_mbox', 'archive_mbox');
    foreach ($opts as $opt) {
      if ($value = $prefs[$opt]) {
        if ($value != 'INBOX' && !preg_match($regexp, $value)) {
          $prefs[$opt] = $prefix.$value;
        }
      }
    }

    if (!empty($prefs['default_folders'])) {
      foreach ($prefs['default_folders'] as $idx => $name) {
        if ($name != 'INBOX' && !preg_match($regexp, $name)) {
          $prefs['default_folders'][$idx] = $prefix.$name;
        }
      }
    }

    if (!empty($prefs['search_mods'])) {
      $folders = array();
      foreach ($prefs['search_mods'] as $idx => $value) {
        if ($idx != 'INBOX' && $idx != '*' && !preg_match($regexp, $idx)) {
          $idx = $prefix.$idx;
        }
        $folders[$idx] = $value;
      }
      $prefs['search_mods'] = $folders;
    }

    if (!empty($prefs['message_threading'])) {
      $folders = array();
      foreach ($prefs['message_threading'] as $idx => $value) {
        if ($idx != 'INBOX' && !preg_match($regexp, $idx)) {
          $idx = $prefix.$idx;
        }
        $folders[$prefix.$idx] = $value;
      }
      $prefs['message_threading'] = $folders;
    }

    if (!empty($prefs['collapsed_folders'])) {
      $folders     = explode('&&', $prefs['collapsed_folders']);
      $count       = count($folders);
      $folders_str = '';

      if ($count) {
          $folders[0]        = substr($folders[0], 1);
          $folders[$count-1] = substr($folders[$count-1], 0, -1);
      }

      foreach ($folders as $value) {
        if ($value != 'INBOX' && !preg_match($regexp, $value)) {
          $value = $prefix.$value;
        }
        $folders_str .= '&'.$value.'&';
      }
      $prefs['collapsed_folders'] = $folders_str;
    }

    $prefs['namespace_fixed'] = true;

    // save updated preferences and reset imap settings (default folders)
    $user->save_prefs($prefs);
    $this->set_storage_prop();
  }


    /**
     * Overwrite action variable
     *
     * @param string New action value
     */
    public function overwrite_action($action)
    {
        $this->action = $action;
        $this->output->set_env('action', $action);
    }


    /**
     * Send the given message using the configured method.
     *
     * @param object $message    Reference to Mail_MIME object
     * @param string $from       Sender address string
     * @param array  $mailto     Array of recipient address strings
     * @param array  $smtp_error SMTP error array (reference)
     * @param string $body_file  Location of file with saved message body (reference),
     *                           used when delay_file_io is enabled
     * @param array  $smtp_opts  SMTP options (e.g. DSN request)
     *
     * @return boolean Send status.
     */
    public function deliver_message(&$message, $from, $mailto, &$smtp_error, &$body_file = null, $smtp_opts = null)
    {
        $headers = $message->headers();

        // send thru SMTP server using custom SMTP library
        if ($this->config->get('smtp_server')) {
            // generate list of recipients
            $a_recipients = array($mailto);

            if (strlen($headers['Cc']))
                $a_recipients[] = $headers['Cc'];
            if (strlen($headers['Bcc']))
                $a_recipients[] = $headers['Bcc'];

            // clean Bcc from header for recipients
            $send_headers = $headers;
            unset($send_headers['Bcc']);
            // here too, it because txtHeaders() below use $message->_headers not only $send_headers
            unset($message->_headers['Bcc']);

            $smtp_headers = $message->txtHeaders($send_headers, true);

            if ($message->getParam('delay_file_io')) {
                // use common temp dir
                $temp_dir = $this->config->get('temp_dir');
                $body_file = tempnam($temp_dir, 'rcmMsg');
                if (PEAR::isError($mime_result = $message->saveMessageBody($body_file))) {
                    self::raise_error(array('code' => 650, 'type' => 'php',
                        'file' => __FILE__, 'line' => __LINE__,
                        'message' => "Could not create message: ".$mime_result->getMessage()),
                        TRUE, FALSE);
                    return false;
                }
                $msg_body = fopen($body_file, 'r');
            }
            else {
                $msg_body = $message->get();
            }

            // send message
            if (!is_object($this->smtp)) {
                $this->smtp_init(true);
            }

            $sent = $this->smtp->send_mail($from, $a_recipients, $smtp_headers, $msg_body, $smtp_opts);
            $smtp_response = $this->smtp->get_response();
            $smtp_error = $this->smtp->get_error();

            // log error
            if (!$sent) {
                self::raise_error(array('code' => 800, 'type' => 'smtp',
                    'line' => __LINE__, 'file' => __FILE__,
                    'message' => "SMTP error: ".join("\n", $smtp_response)), TRUE, FALSE);
            }
        }
        // send mail using PHP's mail() function
        else {
            // unset some headers because they will be added by the mail() function
            $headers_enc = $message->headers($headers);
            $headers_php = $message->_headers;
            unset($headers_php['To'], $headers_php['Subject']);

            // reset stored headers and overwrite
            $message->_headers = array();
            $header_str = $message->txtHeaders($headers_php);

            // #1485779
            if (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN') {
                if (preg_match_all('/<([^@]+@[^>]+)>/', $headers_enc['To'], $m)) {
                    $headers_enc['To'] = implode(', ', $m[1]);
                }
            }

            $msg_body = $message->get();

            if (PEAR::isError($msg_body)) {
                self::raise_error(array('code' => 650, 'type' => 'php',
                    'file' => __FILE__, 'line' => __LINE__,
                    'message' => "Could not create message: ".$msg_body->getMessage()),
                    TRUE, FALSE);
            }
            else {
                $delim   = $this->config->header_delimiter();
                $to      = $headers_enc['To'];
                $subject = $headers_enc['Subject'];
                $header_str = rtrim($header_str);

                if ($delim != "\r\n") {
                    $header_str = str_replace("\r\n", $delim, $header_str);
                    $msg_body   = str_replace("\r\n", $delim, $msg_body);
                    $to         = str_replace("\r\n", $delim, $to);
                    $subject    = str_replace("\r\n", $delim, $subject);
                }

                if (ini_get('safe_mode'))
                    $sent = mail($to, $subject, $msg_body, $header_str);
                else
                    $sent = mail($to, $subject, $msg_body, $header_str, "-f$from");
            }
        }

        if ($sent) {
            $this->plugins->exec_hook('message_sent', array('headers' => $headers, 'body' => $msg_body));

            // remove MDN headers after sending
            unset($headers['Return-Receipt-To'], $headers['Disposition-Notification-To']);

            // get all recipients
            if ($headers['Cc'])
                $mailto .= $headers['Cc'];
            if ($headers['Bcc'])
                $mailto .= $headers['Bcc'];
            if (preg_match_all('/<([^@]+@[^>]+)>/', $mailto, $m))
                $mailto = implode(', ', array_unique($m[1]));

            if ($this->config->get('smtp_log')) {
                self::write_log('sendmail', sprintf("User %s [%s]; Message for %s; %s",
                    $this->user->get_username(),
                    $_SERVER['REMOTE_ADDR'],
                    $mailto,
                    !empty($smtp_response) ? join('; ', $smtp_response) : ''));
            }
        }

        if (is_resource($msg_body)) {
            fclose($msg_body);
        }

        $message->_headers = array();
        $message->headers($headers);

        return $sent;
    }


    /**
     * Unique Message-ID generator.
     *
     * @return string Message-ID
     */
    public function gen_message_id()
    {
        $local_part  = md5(uniqid('rcmail'.mt_rand(),true));
        $domain_part = $this->user->get_username('domain');

        // Try to find FQDN, some spamfilters doesn't like 'localhost' (#1486924)
        if (!preg_match('/\.[a-z]+$/i', $domain_part)) {
            foreach (array($_SERVER['HTTP_HOST'], $_SERVER['SERVER_NAME']) as $host) {
                $host = preg_replace('/:[0-9]+$/', '', $host);
                if ($host && preg_match('/\.[a-z]+$/i', $host)) {
                    $domain_part = $host;
                }
            }
        }

        return sprintf('<%s@%s>', $local_part, $domain_part);
    }


    /**
     * Returns RFC2822 formatted current date in user's timezone
     *
     * @return string Date
     */
    public function user_date()
    {
        // get user's timezone
        try {
            $tz   = new DateTimeZone($this->config->get('timezone'));
            $date = new DateTime('now', $tz);
        }
        catch (Exception $e) {
            $date = new DateTime();
        }

        return $date->format('r');
    }


    /**
     * E-mail address validation.
     *
     * @param string $email Email address
     * @param boolean $dns_check True to check dns
     *
     * @return boolean True on success, False if address is invalid
     */
    public function check_email($email, $dns_check=true)
    {
        // Check for invalid characters
        if (preg_match('/[\x00-\x1F\x7F-\xFF]/', $email)) {
            return false;
        }

        // Check for length limit specified by RFC 5321 (#1486453)
        if (strlen($email) > 254) {
            return false;
        }

        $email_array = explode('@', $email);

        // Check that there's one @ symbol
        if (count($email_array) < 2) {
            return false;
        }

        $domain_part = array_pop($email_array);
        $local_part  = implode('@', $email_array);

        // from PEAR::Validate
        $regexp = '&^(?:
	        ("\s*(?:[^"\f\n\r\t\v\b\s]+\s*)+")| 			 	            #1 quoted name
	        ([-\w!\#\$%\&\'*+~/^`|{}=]+(?:\.[-\w!\#\$%\&\'*+~/^`|{}=]+)*)) 	#2 OR dot-atom (RFC5322)
	        $&xi';

        if (!preg_match($regexp, $local_part)) {
            return false;
        }

        // Check domain part
        if (preg_match('/^\[*(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])(\.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9])){3}\]*$/', $domain_part)) {
            return true; // IP address
        }
        else {
            // If not an IP address
            $domain_array = explode('.', $domain_part);
            // Not enough parts to be a valid domain
            if (sizeof($domain_array) < 2) {
                return false;
            }

            foreach ($domain_array as $part) {
                if (!preg_match('/^(([A-Za-z0-9][A-Za-z0-9-]{0,61}[A-Za-z0-9])|([A-Za-z0-9]))$/', $part)) {
                    return false;
                }
            }

            if (!$dns_check || !$this->config->get('email_dns_check')) {
                return true;
            }

            if (strtoupper(substr(PHP_OS, 0, 3)) == 'WIN' && version_compare(PHP_VERSION, '5.3.0', '<')) {
                $lookup = array();
                @exec("nslookup -type=MX " . escapeshellarg($domain_part) . " 2>&1", $lookup);
                foreach ($lookup as $line) {
                    if (strpos($line, 'MX preference')) {
                        return true;
                    }
                }
                return false;
            }

            // find MX record(s)
            if (getmxrr($domain_part, $mx_records)) {
                return true;
            }

            // find any DNS record
            if (checkdnsrr($domain_part, 'ANY')) {
                return true;
            }
        }

        return false;
    }


    /**
     * Write login data (name, ID, IP address) to the 'userlogins' log file.
     */
    public function log_login()
    {
        if (!$this->config->get('log_logins')) {
            return;
        }

        $user_name = $this->get_user_name();
        $user_id   = $this->get_user_id();

        if (!$user_id) {
            return;
        }

        self::write_log('userlogins',
            sprintf('Successful login for %s (ID: %d) from %s in session %s',
                $user_name, $user_id, self::remote_ip(), session_id()));
    }


    /**
     * Check whether the HTTP referer matches the current request
     *
     * @return boolean True if referer is the same host+path, false if not
     */
    public static function check_referer()
    {
        $uri = parse_url($_SERVER['REQUEST_URI']);
        $referer = parse_url(rcube_request_header('Referer'));
        return $referer['host'] == rcube_request_header('Host') && $referer['path'] == $uri['path'];
    }


    /**
     * Garbage collector function for temp files.
     * Remove temp files older than two days
     */
    public function temp_gc()
    {
        $tmp = unslashify($this->config->get('temp_dir'));
        $expire = mktime() - 172800;  // expire in 48 hours

        if ($dir = opendir($tmp)) {
            while (($fname = readdir($dir)) !== false) {
                if ($fname{0} == '.') {
                    continue;
                }

                if (filemtime($tmp.'/'.$fname) < $expire) {
                    @unlink($tmp.'/'.$fname);
                }
            }

            closedir($dir);
        }
    }

}