[feature/auth-refactor] Move auth providers to separate directory

Moves the provider files to their own directory per bantu's
suggestion.

PHPBB3-9734

phpBB/includes/auth/provider/interface.php

@@ -0,0 +1,93 @@
+<?php
+/**
+*
+* @package auth
+* @copyright (c) 2013 phpBB Group
+* @license http://opensource.org/licenses/gpl-2.0.php GNU General Public License v2
+*
+*/
+
+/**
+* @ignore
+*/
+if (!defined('IN_PHPBB'))
+{
+	exit;
+}
+
+/**
+ * The interface authentication provider classes have to implement.
+ *
+ * @package auth
+ */
+interface phpbb_auth_provider_interface
+{
+	/**
+	 * Checks whether the user is currently identified to the authentication
+	 * provider.
+	 * Called in acp_board while setting authentication plugins.
+	 * Changing to an authentication provider will not be permitted in acp_board
+	 * if there is an error.
+	 *
+	 * @return 	boolean|string 	False if the user is identified, otherwise an
+	 *							error message, or null if not implemented.
+	 */
+	public function init();
+
+	/**
+	 * Performs login.
+	 *
+	 * @param	string	$username 	The name of the user being authenticated.
+	 * @param	string	$password	The password of the user.
+	 * @return	array	An associative array of the format:
+	 *						array(
+	 *							'status' => status constant
+	 *							'error_msg' => string
+	 *							'user_row' => array
+	 *						)
+	 */
+	public function login($username, $password);
+
+	/**
+	 * Autologin function
+	 *
+	 * @return 	array|null	containing the user row, empty if no auto login
+	 * 						should take place, or null if not impletmented.
+	 */
+	public function autologin();
+
+	/**
+	 * This function is used to output any required fields in the authentication
+	 * admin panel. It also defines any required configuration table fields.
+	 *
+	 * @param 	array 	$new 	Contains the new configuration values that have
+	 * 							been set in acp_board.
+	 * @return	array|null	Returns null if not implemented or an array of the
+	 *						form:
+	 *							array(
+	 *								'tpl'		=> string
+	 *								'config' 	=> array
+	 *							)
+	 */
+	public function acp($new);
+
+	/**
+	 * Performs additional actions during logout.
+	 *
+	 * @param 	array	$data			An array corresponding to
+	 *									phpbb_session::data
+	 * @param 	boolean	$new_session	True for a new session, false for no new
+	 *									session.
+	 */
+	public function logout($data, $new_session);
+
+	/**
+	 * The session validation function checks whether the user is still logged
+	 * into phpBB.
+	 *
+	 * @param 	array 	$user
+	 * @return 	boolean	true if the given user is authenticated, false if the 
+	 * 					session should be closed, or null if not implemented.
+	 */
+	public function validate_session($user);
+}