Tag Archives: ACL

Central ACL Check

With checking ACL’s, the code I use is as follows:

$info = $this->Member->read(null, $id);

// Check for permissions to edit this account
if ( !$this->Acl->check(array('model' => 'Member', 'foreign_key' => $this->Auth->user('member_id')), $info['Member']['username'], 'update') ) {
	$this->Session->setFlash(__('You are not allowed to edit this user. -- ' . $this->Auth->user('member_id'), true));

While this works and is not that bad of an idea at all, there is a way to centralize this check and put it in the main app_controller.php file.
Continue reading Central ACL Check

ACL Implementation

After doing a few posts on Access Control Lists (ACLs), the need to look further into the implementation of ACLs in a CakePHP project could be helpful. If there are questions on setting up the ACL tri-table in the database, you can review the previous postings, or check out the CakePHP documentation. But now that you have the ACL tables set up, how does it actually work?

First, the ACL happens after authentication. So whether or not you are using the Auth component, you will still need to authenticate the user some how, some way. Then once the user is authenticated and logged in, that user will have permissions to do different thing. Let’s say one of those things is to edit accounts. If it is a regular user, he should be able to edit his own and no one else. If the user was a “site admin” he should be able to edit his own and any account that is not a “super-admin”. If he is a super admin then he should edit everyone’s account. However, the first part of this is setting up the initial ACL permissions.

Continue reading ACL Implementation

Access Control Lists (ACLs) Part 3

In the first part, the idea and theory behind an ACL was discussed. In part 2, the set up of AROs, ACOs, and ACLs via the command line was shown. Now in part three, we look at why this is so important. Because an interactive site with memberships should never be static, what happens when a new member signs up? What happens when a member is promoted to an “admin” level? And what happens when users change? This can all be happened via ACLs.

In part 2, existing member were set up as AROs. And with user accounts, we also have to set those up as ACOs. Then those AROs (people) need to have permissions set for the CRUD actions. (Create, Read, Update, Delete). These actions are specific to the ACO, or object they are trying to manipulate. So if a user wants to edit their own account, do they have permission? If a user wants to delete another person’s account, do they have permissions to? With setting up ACLs, this can be checked. But what do we do when a new person signs up for an account? We need to create the code to do this.

In the Users Controller, we need to make sure we use the ACL component is included. So include this in the controller:

class UsersController extends AppController {
	var $name = 'Users';
	var $components = array('Acl');

Also remember that the Auth and Security components are also very powerful components and should be included as well, but the above only shows where to include the components. Now with this in place, we can no address the add (or register) function of the controller.

Continue reading Access Control Lists (ACLs) Part 3

Access Control Lists (ACLs) Part 2

In my last post, I covered a little bit about what an Access Control List (ACL) was. The Cookbook provides a great more detail.

To go along with the idea of the last post, the application has a few different areas: Users who are members of groups, Groups which have users as members, and Events that belong to either the user or the group. Since the creation of ACOs and AROs are basically the same for each area (Users, Groups, Events), I will detail some code for the Users area making use of ACLs.

The first thing we need to do is create an ARO grouping and an ACO grouping. Remember that AROs are the requester of an object. In this example, we can think of them as people. And people have different types of roles, which is what we need to create for the people. In this example application, there will be site admins (Admins), group leaders (Leaders) and regular members (Members). So we need to create this type of ARO. We can do this in a controller, and a page, or we can do this via the command line.

Continue reading Access Control Lists (ACLs) Part 2

Access Control Lists (ACLs)

Access Control Lists, or ACLs, provide a good level of access control on any site. Code bases and platforms may use a different method of instituting ACLs and I am going to go through how CakePHP 1.2.x is handling them.

First is to understand what an ACL really is. The Cookbook has a good page explaining this type of concept. I highly recommend reading through this page. The whole concept behind this ACL can be divided in three parts:

  • ACO – Access Control Object, object that is being requested
  • ARO – Access Request Object, object that is putting in the request
  • ACL – Access Control List, determines if an ARO can access an ACO.

In the Cookbook, they have a very good call out about the ACL, it is not authentication. No matter what code base, or platform you are on, never mistake this. The ACL verification only happens after the person logs in. They can be very powerful together, but authentication must happen first.

The next thing to understand is the way an ACL would look in a matrix. Again, the Cookbook provides a great example of this. The one thing that I would rather prefer, but understand why they do this, is the use of the example. Sure, we all like movies, and the Lord of the Rings is a great way to really explain different things, but it may be hard to switch that over to the real world of coding. So for this entry, I am going to use as an example, and Event Calendar.

Continue reading Access Control Lists (ACLs)