Access Control

Within your controllers you should declare and restrict what people can see and do to ensure that users cannot run actions on the website they shouldn't be able to.

Allowed Actions

Any action you define on a controller must be defined in a $allowed_actions static array. This prevents users from directly calling methods that they shouldn't.

	<?php

	class MyController extends Controller {
		
		private static $allowed_actions = array(
			// someaction can be accessed by anyone, any time
			'someaction', 

			// So can otheraction
			'otheraction' => true, 
			
			// restrictedaction can only be people with ADMIN privilege
			'restrictedaction' => 'ADMIN', 

			// restricted to uses that have the 'CMS_ACCESS_CMSMain' access
			'cmsrestrictedaction' => 'CMS_ACCESS_CMSMain',
			
			// complexaction can only be accessed if $this->canComplexAction() returns true.
			'complexaction' => '->canComplexAction',

			// complexactioncheck can only be accessed if $this->canComplexAction("MyRestrictedAction", false, 42) is true.
			'complexactioncheck' => '->canComplexAction("MyRestrictedAction", false, 42)',
		);
	}

If the permission check fails, SilverStripe will return a 403 Forbidden HTTP status. [/info]

An action named "index" is white listed by default, unless allowed_actions is defined as an empty array, or the action is specifically restricted.

	<?php 

	class MyController extends Controller {

		public function index() {
			// allowed without an $allowed_action defined
		}
	}
	<?php

	class MyExtension extends Extension {

		private static $allowed_actions = array(
			'mycustomaction'
		);
	}
	<?php

	class MyController extends Controller {

		private static $allowed_actions = array(
			'secure',
			// secureaction won't work as it's private.
		);

		public function secure() {
			// ..
		}

		private function secureaction() {
			// ..
		}
	}
	<?php

	class MyController extends Controller {

		private static $allowed_actions = array(
			'action',
		);

		public function action() {
			// ..
		}
	}

	class MyChildController extends MyController {

		private static $allowed_actions = array(
			'action', // required as we are redefining action
		);

		public function action() {

		}
	}

Access checks on parent classes need to be overwritten via the Configuration API. [/notice]

Forms

Form action methods should not be included in $allowed_actions. However, the form method should be included as an allowed_action.

	<?php

	class MyController extends Controller {

		private static $allowed_actions = array(
			'ContactForm' // use the Form method, not the action
		);

		public function ContactForm() {
			return new Form(..);
		}

		public function doContactForm($data, $form) {
			// ..
		}
	}

Each method responding to a URL can also implement custom permission checks, e.g. to handle responses conditionally on the passed request data.

	<?php

	class MyController extends Controller {
		
		private static $allowed_actions = array(
			'myaction'
		);
		
		public function myaction($request) {
			if(!$request->getVar('apikey')) {
				return $this->httpError(403, 'No API key provided');
			} 
				
			return 'valid';
		}
	}

This is recommended as an addition for $allowed_actions, in order to handle more complex checks, rather than a replacement. [/notice]

Controller Level Checks

After checking for allowed_actions, each controller invokes its init() method, which is typically used to set up common state, If an init() method returns a SS_HTTPResponse with either a 3xx or 4xx HTTP status code, it'll abort execution. This behavior can be used to implement permission checks.

init is called for any possible action on the controller and before any specific method such as index.
	<?php

	class MyController extends Controller {
		
		private static $allowed_actions = array();
		
		public function init() {
			parent::init();

			if(!Permission::check('ADMIN')) {
				return $this->httpError(403);
			}
		}
	}

API Documentation