Gollem_Auth::authenticate PHP Method

    public static function authenticate($credentials = array())
    {
        $result = false;
        // Do 'horde' authentication.
        $gollem_app = $GLOBALS['registry']->getApiInstance('gollem', 'application');
        if (!empty($gollem_app->initParams['authentication']) && $gollem_app->initParams['authentication'] == 'horde') {
            if ($registry->getAuth()) {
                return $result;
            }
            throw new Horde_Auth_Exception('', Horde_Auth::REASON_FAILED);
        }
        // Load backend.
        if (!isset($credentials['backend_key'])) {
            $credentials['backend_key'] = self::getPreferredBackend();
        }
        $backend = self::getBackend($credentials['backend_key']);
        // Check for hordeauth.
        if ((!isset($credentials['userId']) || !isset($credentials['password'])) && !$GLOBALS['session']->exists('gollem', 'backend_key') && self::canAutoLogin($credentials['backend_key'])) {
            if (!empty($backend['hordeauth'])) {
                $credentials['userId'] = self::getAutologinID($credentials['backend_key']);
                $credentials['password'] = $GLOBALS['registry']->getAuthCredential('password');
            }
        }
        // Check for hardcoded backend credentials.
        if (!isset($credentials['userId']) && !empty($backend['params']['username'])) {
            $credentials['userId'] = $backend['params']['username'];
        }
        if (!isset($credentials['password']) && !empty($backend['params']['password'])) {
            $credentials['password'] = $backend['params']['password'];
        }
        if (!isset($credentials['userId']) || !isset($credentials['password'])) {
            throw new Horde_Auth_Exception('', Horde_Auth::REASON_BADLOGIN);
        }
        try {
            $vfs = $GLOBALS['injector']->getInstance('Gollem_Factory_Vfs')->create($credentials['backend_key']);
            $params = array('username' => $credentials['userId'], 'password' => $credentials['password']);
            foreach (array_keys($backend['loginparams']) as $param) {
                if (isset($credentials[$param])) {
                    $backend['params'][$param] = $params[$param] = $credentials[$param];
                }
            }
            $vfs->setParams($params);
            $vfs->checkCredentials();
        } catch (Horde_Exception $e) {
            throw new Horde_Auth_Exception($e->getMessage(), Horde_Auth::REASON_MESSAGE);
        }
        // Set current backend.
        Gollem::$backend =& $backend;
        // Mark backend as authenticated.
        $backend['auth'] = true;
        // Save username in backend configuration.
        if (!isset($backend['params']['username'])) {
            $backend['params']['username'] = $credentials['userId'];
        }
        if (!isset($backend['params']['password'])) {
            $backend['params']['password'] = $credentials['password'];
        }
        // Make sure we have a 'root' parameter.
        if (empty($backend['root'])) {
            $backend['root'] = '/';
        }
        $backend['root'] = Horde_Util::realPath($backend['root']);
        // Make sure we have a 'home' parameter.
        if (empty($backend['home'])) {
            $backend['home'] = empty($backend['params']['home']) ? $vfs->getCurrentDirectory() : $backend['params']['home'];
            if (empty($backend['home'])) {
                $backend['home'] = $backend['root'];
            }
        }
        // Make sure the home parameter lives under root if it is a relative
        // directory.
        if (strpos($backend['home'], '/') !== 0) {
            $backend['home'] = $backend['root'] . '/' . $backend['home'];
        }
        $backend['home'] = Horde_Util::realPath($backend['home']);
        $backend['dir'] = $backend['home'];
        // Verify that home is below root.
        if (!Gollem::verifyDir($backend['home'])) {
            throw new Horde_Auth_Exception('Backend Configuration Error: Home directory not below root.', Horde_Auth::REASON_MESSAGE);
        }
        // Create the home directory if it doesn't already exist.
        if ($backend['home'] != '/' && !empty($backend['createhome'])) {
            $pos = strrpos($backend['home'], '/');
            $cr_dir = substr($backend['home'], 0, $pos);
            $cr_file = substr($backend['home'], $pos + 1);
            if (!$vfs->exists($cr_dir, $cr_file)) {
                try {
                    $res = Gollem::createFolder($cr_dir, $cr_file, $vfs);
                } catch (Gollem_Exception $e) {
                    throw new Horde_Auth_Exception('Backend Configuration Error: Could not create home directory ' . $backend['home'] . ': ' . $e->getMessage(), Horde_Auth::REASON_MESSAGE);
                }
            }
        }
        // Write the backend to the session.
        $backends = self::_getBackends();
        $backends[$credentials['backend_key']] = $backend;
        self::_setBackends($backends);
        return array('backend_key' => $credentials['backend_key']);
    }

 /**
  * Tries to authenticate with the server and create a session.
  *
  * @param string $userId      The username of the user.
  * @param array $credentials  Credentials of the user. Allowed keys:
  *                            'backend', 'password'.
  *
  * @throws Horde_Auth_Exception
  */
 public function authAuthenticate($userId, $credentials)
 {
     $this->init();
     if (empty($credentials['backend_key'])) {
         $credentials['backend_key'] = Gollem_Auth::getPreferredBackend();
     }
     $credentials['userId'] = $userId;
     $this->_addSessVars(Gollem_Auth::authenticate($credentials));
 }