php – Random IT Stuff

Quick and dirty PlaySMS LDAP auth

PlaySMS is some awesome Open Souce SMS software but it lacks a couple of features for our use case, one of which was some form of centralised auth. Ultimately I’d like to write a proper plugin to allow SAML auth so we can front this with AzureAD but for now, as it’s at on premise anyway, we’ll have to make do with this bodgey LDAP integration.

Bear in mind that with this in place you’ll no longer be able login with any internal PlaySMS credentials so ensure that you create a user that matches your LDAP username and grant it admin permission before you apply this modification. It would of course be a trivial change to make this try to auth via the DB, then fail back to LDAP or vice versa if that’s what you’d prefer.

Anyway, open up plugins/core/auth/fn.php and replace

$db_query = "SELECT password,salt FROM " . _DB_PREF_ . "_tblUser WHERE flag_deleted='0' AND username='$username'";
	$db_result = dba_query($db_query);
	$db_row = dba_fetch_array($db_result);
	$res_password = trim($db_row['password']);
	$res_salt = trim($db_row['salt']);
	$password = md5($password . $res_salt);
	if ($password && $res_password && ($password == $res_password)) {

with

$ldapserver= "ldaps://ldapservername";
$ldap = ldap_connect($ldapserver);
$bind = @ldap_bind($ldap, $username . "@domainname.tld", $password);
if ($bind) {

Told you it was quick and dirty, but it works. Obviously you’ll need to ensure that you create users within PlaySMS that match the users in LDAP, we’re currently shoving this directly into the MySQL database.

You’ll also need to install the PHP LDAP extension.

Moodle authentication against ASP.NET identity services database

Picture the scene – you have a custom enrolment application using ASP.NET identity for authentication and from out of nowhere someone decides that the users now need to be able to login to a VLE to complete assignments. Moodle already has a external database plugin so it can’t be too hard, except it doesn’t support the hashing that identity uses.

Given the short timescale to implement and crazy workload I of course went looking to see if anyone else had done this. There are some threads on Stack Exchange where people have tried to do the same thing and lots of info about how the hashing works so I set about porting the code to PHP only to find that someone had already done a much better job than I’d ever do. Thanks MDHearingAid.

So I cloned the repo and set about bodging it into Moodle. My bodge is not pretty but it works. If you want to do the same thing you can download my patch file (apologies for the Zip, WordPress won’t accept plain text files for some reason) and go at it, just don’t judge me too harshly. This is a patch against Moodle 3.8 but will probably/possibly work against other versions.

moodleauthdb Download

Obviously you need connectivity to the database that Identity Services is running on. So you’ll probably want to install Microsoft Drivers for PHP for SQL Server if you haven’t already and then set up your connection in Moodle under Site Administration -> Plugins -> Authentication -> External database. The table name will most likely be AspNetUsers. Username = Username , Password = PasswordHash. Under password format you should now see ASP.NET Identity Service or maybe just [[identityservice]] if my patch to the language file didn’t work properly.