Issue #22 - Created bootstrap.php to intercept the execution before Moodle finished loading.

bootstrap.php

@@ -0,0 +1,64 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle 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 more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+/**
+ * This file should run before config.php requires '/lib/setup.php'.
+ *
+ * Main purpose of this file:
+ * 1) Allow to 'file.php' to know where dataroot is located and serve files during a maintenance.
+ * 2) Allow to 'pretend' maintenance mode for non-allowed IPs by calling 'climaintenance.php'.
+ * 3) Set a flag that this file was loaded so we can warn users if this config is not working.
+ *
+ * @package    auth_outage
+ * @author     Daniel Thee Roperto <daniel.roperto@catalyst-au.net>
+ * @copyright  2016 Catalyst IT
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ *
+ * @var stdClass $CFG
+ */
+
+// This file does nothing if running from CLI.
+if (defined('CLI_SCRIPT') && CLI_SCRIPT) {
+    return;
+}
+
+// 1) Are we fetching a file? Non-allowed IPs can still see them.
+if (defined('AUTH_OUTAGE_FILE')) {
+    // We are not using any external libraries or references in this file (cli maintenance is active).
+    // If you change the path below maybe you need to change maintenance_static_page::get_resources_folder() as well.
+    $resourcedir = $CFG->dataroot.'/auth_outage/climaintenance';
+
+    // Protect against path traversal attacks.
+    $file = $resourcedir.'/'.$_GET['file'];
+    if (realpath($file) !== $file) {
+        // @codingStandardsIgnoreStart
+        error_log('Invalid file: '.$_GET['file']);
+        // @codingStandardsIgnoreEnd
+        http_response_code(404);
+        die('Not found.');
+    }
+
+    readfile($file);
+    exit(0);
+}
+
+// 2) Check for allowed IPs during outages.
+if (file_exists($CFG->dataroot.'/climaintenance.php')) {
+    $CFG->dirroot = dirname(dirname(dirname(__FILE__))); // It is not defined yet but the script below needs it.
+    require($CFG->dataroot.'/climaintenance.php'); // This call may terminate the script here or not.
+}
+
+// 3) Set flag this file was loaded.
+$CFG->auth_outage_check = 2;