George Mason University Antonin Scalia Law School

How to Disable Plugins Outside MODX Manager

Since we are using CAS Authentication plugin to add an extra security layer to our MODX Manager, we need a way to disable the plugin in case something goes wrong and we don’t want to get locked out of our own site. Here are the steps to disable plugins outside the Manager:

  1. Log into the cloud dashboard and temporarily add phpMyAdmin to the cloud
  2. Log into phpMyAdmin, browse the modx_site_plugins table for the CAS plugin, double-click on the disable column to change the value from 0 to 1 to disable the plugin
  3. Manually clear the cache by logging into sFTP and delete everything in the core/cache directory
  4. Log back into the cloud dashboard to turn off phpMyAdmin

Simple CAS Authentication

The following script makes a private web site accessible only to authenticated users. For example, if you have a career services web site and you only want students to access the materials using their email (university) credentials, this script would do the trick. You don’t need to create separate accounts  for the site.

1. Download phpCAS and unzip/untar it: https://wiki.jasig.org/display/CASC/phpCAS.

2. Place the entire phpCAS directory on your server.

3. Place the following codes in at the top of any .php file that you want the contents to be private. If you want to make the entire site private, just add the script to an include file in the header. The following script is based on a simple CAS client:

<?php

/**
* Example for a simple cas 2.0 client
*
* PHP Version 5
*
* @file example_simple.php
* @category Authentication
* @package PhpCAS
* @author Joachim Fritschi <jfritschi@freenet.de>
* @author Adam Franco <afranco@middlebury.edu>
* @license http://www.apache.org/licenses/LICENSE-2.0 Apache License 2.0
* @link https://wiki.jasig.org/display/CASC/phpCAS
*/

// Load the settings from the central config file
// require_once 'config.php'; /*commented out by Donny*/
// Load the CAS lib
require_once $phpcas_path . '/CAS.php'; /*This is the path that to the CAS directory on your server, not the URL*/

// Uncomment to enable debugging
phpCAS::setDebug();

// Initialize phpCAS
phpCAS::client(CAS_VERSION_2_0, $cas_host, $cas_port, $cas_context);
//example: phpCAS::client(CAS_VERSION_1_0, 'login.gmu.edu', 443,'');

// For production use set the CA certificate that is the issuer of the cert
// on the CAS server and uncomment the line below
// phpCAS::setCasServerCACert($cas_server_ca_cert_path);

// For quick testing you can disable SSL validation of the CAS server.
// THIS SETTING IS NOT RECOMMENDED FOR PRODUCTION.
// VALIDATING THE CAS SERVER IS CRUCIAL TO THE SECURITY OF THE CAS PROTOCOL!
phpCAS::setNoCasServerValidation();

// force CAS authentication
phpCAS::forceAuthentication();

// at this step, the user has been authenticated by the CAS server
// and the user's login name can be read with phpCAS::getUser().

// logout if desired
if (isset($_REQUEST['logout'])) {
phpCAS::logout();
}

// for this test, simply print that the authentication was successfull
?>

4. Add the following script to your HTML file to indicate if the user is logged in and also to the allow the user to sign off.

<div>Not <strong><?php echo phpCAS::getUser(); ?></strong>? <a href="?logout=">Sign out</a></div>

phpCAS and WordPress

Make sure your account is in the “Administrator” role, as you won’t be able to login as admin after switching to CAS.

1. Download phpCAS and unzip/untar it: https://wiki.jasig.org/display/CASC/phpCAS

2. Download wpcas.zip and unzip it in wp-content/plugins

3. edit wp-content/plugins/wpcas/wpcas.php and remove or comment out line 57:

/* $wpcas_options['server_path'] == '' || */

4. Create wp-content/plugins/wpcas/wpcas-conf.php with the following content (change “/path/to” to the path to CAS.php that you installed in step 1):

<?php

// the configuration array

$wpcas_options = array(

'cas_version' => 'S1',

'include_path' => '/path/to/CAS.php',

'server_hostname' => 'login.gmu.edu',

'server_port' => '443',

'server_path' => ''

);

// this function gets executed

// if the CAS username doesn't match a username in WordPress

function wpcas_nowpuser( $user_name ){

die('you do not have permission here');

}

?>

4. Login with an account that’s in the Administrator role.  In “Plugins”, activate the wpCAS plugin.

5. If possible, test in a separate browser.  When you click “Log in” you should be redirected to https://login.gmu.edu.  Type in your PatriotPass NetID and password.  You should be redirected back to your WordPress site.