php role based access control system - permission on pages basis

Question

I am going to design a system. System has 3 users types. Admin, Managers, Developers. Application is consists with 100 php UI pages.

1. database table is like this ( page, admin, manager, developer). page is the pagename, admin, manager, developer are boolean fields. If perticular field is 1 or true role has the permission to access.
2. Now I need to synchronize the database with all 100 pages. I know the which role the logged in user is belongs. But I don't know how to pass the page and match it with table to check whether the particular user has access.

My plan is to put checkpermission($_SERVER['PHP_SELF'], $role); to each page. How should I do this properly ? Is it ok if I put this line to header.php. Will it be bad design ?

My leads main concern is extendability. He want to plug another site without changing much. Also we want to give a page. Admin can use that page to give, remove permissions. add subdirectory to the permission tree.

Answer 1

$ROLID = $_SESSION['ROLID'];
if($ROLID == 2 || $ROLID == 3) header('Location: 'www.foo.com/home.php');

So Admin's are role ID 1, which gains them access to any page. If a user with a role ID of 2 or 3 (managers or developers) they will be redirected to the home page.

Put this code at the top of the page.