LDAP Groups Authorization

Question

Hi,
I have read some of the forum threads about LDAP Group Authorization - I remain confused. Here's the problem I am trying to solve.
I was successfull in setting my Authentication to "Based on authentication scheme from gallery:Existing Login Page: Use LDAP Directory Credentials" -
That works fine, But I would not like all users in my OID LDAP directory to log into my application- Which is why I have created a group for the user I want to include in my OID directory.
Now at the " Builder->Application...->Security->Authorization Schemes->
I have created an Authorization Scheme as "PL/SQL Function returing a booloean" .
My Scheme Source(Identify Query or PL/SQL) is as follows and is set to "once Per session"
return wwv_flow_ldap.is_member
(:APP_USER,
null,
'cn=users,dc=wellesley,dc=edu',
'jadeland.wellesley.edu',
'389',
'wcd_HTMLDB',
'cn=portal.040323.1220,cn=Groups, dc=wellesley,dc=edu');
where in my LDAP directory, 'wcd_HTMLDB' is the subgroup under group "portal.040323.1220" -
I have included 3 users in the group 'wcd_HTMLDB' .
Still the login page allows all LDAP user ( and not just the 3 from the 'wcd_HTMLDB' group.
Where did I go wrong -?
What 's the proper way to authorise only LDAP users in a group ?
Any help would be really appreciated.
Thanks .

Answer 1

Indira,
The public synonym (and grant execute) must be created after that package is compiled which can happen after catldap is run in your database. This is only a problem if catldap has not been run before HTML DB is installed. That's described in the flows/doc/ldap.html file in the distribution directory (not very prominently, we know).
When you initially attached the authorization scheme to your login page and it wouldn't let you in, the reason is that it was using the value of APP_USER to drive your lookup function. But when the login page is rendered, APP_USER is null because you haven't logged in yet. So a user-based authorization scheme on a login page can never work.
When you changed the ldap username edit function the way you did, you achieved the goal of preventing an unauthorized user from using the login page to authenticate. Looks like the way it's set up is to give unauthorized users an authentication error, which is a little misleading (saying their credentials are invalid when in fact they are valid but they aren't authorized to use your application), but if it suits your purpose, great. You should consider that if you change the authentication method to, say Single Sign-On, you'll then want to use authorization schemes to keep unauthorized users out. So the authorization scheme that you first set about using would be fine in that case, so long as you adjust the code to allow for visits to public pages prior to authentication (v('APP_USER') = 'HTMLDB_PUBLIC_USER'). However, you'd want to attach that scheme to the application itself (Edit Application Attributes->Authorization) so it fires on every page. Evaluating a scheme like that on every page view rather that once per session probably works best, even better if you cache the result of the evaluation yourself for performance reasons, e.g., set an application item to some value the first time the authenticated user passes the ldap membership test, then using that item as an 'already passed' flag for subsequent invocations.
Finally, I assume you are using the built-in ldap_dnprep function because you need to replace '.' with '_' in the username value entered by the user. If that is not your requirement, let's talk.
Scott