Miscellaneous Hacks - LDAP Authentication

I've only recently started using vBulletin, and this is my first mod so if you use this, please click Installed!

This mod (which builds on the fine work from malcomx and zemic) is intended to lower the barriers to using and LDAP directory as an external authentication source for your board. The idea is simple; capture a login attempt before authentication and test it against LDAP first, if that succeeds, see if there is already a matching user in vBulletin. If there is not, create one, using data from the LDAP to fill in the required fields, if there is already a matching user (Determined by comparing email addresses) then update the user.

You might be asking why this mod is better than the two mods I've mentioned above? Well firstly the only additional file is the XML file for the new hooks (See below), and no changes to vBulletin code so installation is simple, and upgrades to vBulletin don't get over complicated by re-applying changes. Secondly, all the settings are controlled from the admincp rather than an external config file. Thirdly (as if two wasn't enough) I've added some hook points so this mod can be extended, for example to get additional data from the LDAP and put it in user profile fields.

One important similarity with the two earlier mods is that in the admincp and modcp no LDAP authentication is performed, this is a safety feature, so even if the mod or an extending to it, breaks your board, you shouldn't ever get locked out of the admincp so you'll be able to turn if off quickly.

Additional Hooks

The mod is essentially a single plugin (plus options and help) which runs at global_complete which is before most other things have happened, but just after all the global setup has occurred.

To enable the additional hooks, you need to upload the file hooks_ldap_auth.xml to /includes/xml under your forum.

The following new hooks are created by this mod:

• ldap_auth_start - After the list of attributes to fetch has been created, this list is in $ldapAttrs. You can simply add your own attributes to this array here.
• ldap_auth_all_user - After a new user has been added to vBulletin or existing user has been updated, but before the user has been saved. The new user is in $newuser and the LDAP data is in $userData. This happens before ldap_auth_new_user or ldap_auth_existing_user.
• ldap_auth_new_user - After a new user has been added to vBulletin, but before the user has been saved. The new user is in $newuser and the LDAP data is in $userData.
• ldap_auth_existing_user - After an existing user has been updated, but before the user has been saved. The new user is in $newuser and the LDAP data is in $userData.

By requesting new attributes at ldap_auth_start and then applying them at either ldap_auth_all_user, ldap_auth_new_user or ldap_auth_existing_user you can setup your users easily without having to write all the LDAP code yourself!

AdminCP Settings

This mod creates a new options group called LDAP Authentication between email options and user registration options where you set the host name and port number of the LDAP server, the initial authentication type (Anonymous or authenticated), optionally the BindDN and Password for the LDAP server. You also set which attribute matches the vBulletin username (The default is cn which works well for inetOrgPerson based entries). You can set additional attributes to retrieve (If you want to quickly knock up a simple plugin which uses them at one of the hook points above). There is also the facility to disable (or rather make unavailable) accounts which exist in vBulletin but not in LDAP. Given that your initial admin may fall into this group, there is also a list of userids who should be allowed to log in anyway.

Requirements

• PHP 4.3+ with LDAP support.

I'll try to provide support to users of my mod, but please bear in mind I fairly new to all this, so I may not be able to solve all problems immediately. Support will only be provided via this thread (Don't PM or email me unless I ask you to). Priority will be given to users who have clicked Installed.

Release Notes

• 1.0 - Initial release
• 1.1 - Corrected SQL queries to use TABLE_PREFIX
• 1.2 - Corrected a bug which prevented the settings page from being created correctly
• 1.3 - Corrected where the existing, new and all user hooks are called (Before, not after the user profile fields are set) to support dependant plugins
• 1.4 - Added the ability to set a search base for directories which do not permit searching from the root
• 1.5 - Fixed reported bug where hooks were called in the wrong order

Installation

1. Add the command define('DISABLE_PASSWORD_CLEARING', 1); to your includes/config.php - This will NOT be overwritten by upgrades, so only needs doing once.
2. Upload the file hooks_ldap_auth.xml to includes/xml under your forum.
3. Install the latest product file (below) using the Add/Import Product link on the Manage Products page under Plugins & Products in your AdminCP.

Haqa...

[Haqa]

Ok, so how do you use the hooks to make a mod which can use and extend ldap_auth?

Roughly like this:

1. Set a plugin on hook ldap_auth_start which adds the additional LDAP attributes you'll be using to the array $ldapAttrs.
2. Choose when you want to use the attributes:
   • If you want to use them every time a user logs in, plug in at hook ldap_auth_all_user
   • If you only want to use them if the user has never logged in before choose ldap_auth_new_user
   • If you want to use them only if the user HAS logged in before, choose ldap_auth_existing_user
3. Whichever hook (or hooks) you choose the process is the same:
   • If you want to add data to the user, you'll find the users datamanager object in the variable $newuser
   • If you want to set a value into the users profile fields, then you just need to set that value into the array $userFields with the key being the field name

There are, of course, many other things you could choose to do in your plugin, for example if you call the standard_error function, you'll display a nice error message page (For example if the user has a flag denoting the account is disabled) HOWEVER you need to call process_logout() first as the user will be partly logged in (If their account already exists in vBulletin).

Examples of this can be found in the LDAP Authentication plugin in this mod, or in the Full Name Support for LDAP Auth and Location Support for LDAP Auth mods (Coming soon).

Hope this helps

Haqa...

[codershark]

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[Haqa]

Originally Posted by codershark

Absolutly Great Timepoint where you post it, because I need it for my exam !

Thanks !

Well be careful, I don't claim that the code is perfect, only that it works for me - There may well be hidden bugs, or aspects of vBulletin that I don't understand properly yet.

Good luck with your exam!

H.

[codershark]

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[Lionel]

You should use TABLE_PREFIX for vbulletin :-)

[daFish]

Great to see this addon and I have one single question as of now: What if I use this with an empty directory? Does this addon automatically inserts the users to the LDAP?

[Haqa]

Originally Posted by Lionel

You should use TABLE_PREFIX for vbulletin :-)

You are right, I should (And I though I did...). I'll fix this and release an update.

Originally Posted by daFish

Great to see this addon and I have one single question as of now: What if I use this with an empty directory? Does this addon automatically inserts the users to the LDAP?

No, the way it works is it takes users from the directory and creates them in vBulletin as they log in. It doesn't work the other way round.

There are a number of good tools for LDAP management, I use yala, though this does open a potential security hole unless you are VERY careful (It exposes your LDAP to the internet via the web).

H.

[daFish]

Originally Posted by Haqa

No, the way it works is it takes users from the directory and creates them in vBulletin as they log in. It doesn't work the other way round.

There are a number of good tools for LDAP management, I use yala, though this does open a potential security hole unless you are VERY careful (It exposes your LDAP to the internet via the web).

I don't know if this is achievable, but it would be great if there would be an tool for synchronize the user databases, especially if you try to connect your forum to an backend with LDAP as the authentification service.

[Freezerator]

Nice hack, planning on using this in the future to have only one userdatabase