Moodle plugins directory: SAML2 Single sign on | Moodle.org
SAML2 Single sign on
Brendan Heywood, 
Rossco HellmansWhat is this?
This plugin does authentication, user auto creation with field mapping.
Why is it better?
- 100% configured in the Moodle GUI - no installation of a whole separate app, and no touching of config files or generating certificates.
- Minimal configuration needed, in most cases just copy the IdP metadata in and then give the SP metadata to your IdP admin and that's it.
- Fast! - 3 redirects instead of 7
- Supports back channel Single Logout which most big organisations require (unlike OneLogin)
How does it work?
It completely embeds a SimpleSamlPHP instance as an internal dependancy which is dynamically configured the way it should be and inherits almost all of it's configuration from Moodle configuration. In the future we should be able to swap to a different internal SAML implementation and the plugin GUI shouldn't need to change at all.
Features
- Dual login VS forced login for all as an option, with ?saml=off on the login page for manual accounts, and ?saml=on supported everywhere to deep link and force login via saml if dual auth is on.
- SAML attributes to Moodle user field mapping
- Automatic certificate creation
- Optionally auto create users
Features not yet implemented:
- Enrolment - this should be an enrol plugin and not in an auth plugin
- Role mapping - not yet implemented
Installation
1) Install the plugin the same as any standard moodle plugin either via the Moodle plugin directory, or you can use git to clone it into your source:
git clone git@github.com:catalyst/moodle-auth_saml2.git auth/saml2
2) Then run the Moodle upgrade 3) If your IdP has a publicly available XML descriptor, copy this url into the SAML2 auth config settings page 4) If your IdP requires whitelisting each SP then in the settings page is links to download the XML, or you can provide that url to your IdP administrator.
For most simple setups this is enough to get authentication working, there are many more settings to define how to handle new accounts, dual authentication, and to easily debug the plugin if things are not working.
If you have issues please log them in github here:
https://github.com/catalyst/moodle-auth_saml2/issues
Or if you want paid support please contact Catalyst IT Australia:
https://www.catalyst-au.net/contact-us
Testing
This plugin has been tested against:
- SimpleSamlPHP set up as an IdP
- openidp.feide.no
- testshib.org
- An AAF instance of Shibboleth
Other SAML plugins
The diversity and variable quality and features of SAML Moodle plugins is a reflection of a great need for a solid SAML plugin, but the neglect to do it properly in core. SAML2 is by far the most robust and supported protocol across the internet and should be fully integrated into moodle core as both a Service Provider and as an Identity Provider, and without any external dependencies to manage.
Here is a quick run down of the alternatives:
Core:
- /auth/shibboleth - This requires a separately installed and configured Shibbolleth install
One big issue with this, and the category below, is as there is a whole extra application between moodle and the IdP, so the login and logout processes have more latency due to extra redirects. Latency on potentially slow mobile networks is by far the biggest bottle neck for login speed and the biggest complaint by end users in our experience.
Plugins that require SimpleSamlPHP
These are all forks of each other, and unfortunately have diverged quite early or have no common git history making it difficult to cross port features or fixes between them.
Plugins which embed a SAML client lib:
These are generally much easier to manage and configure as they are standalone.
https://moodle.org/plugins/view/auth_onelogin_saml - This one uses it's own embedded saml library which is great and promising, however it doesn't support 'back channel logout' which is critical for security in any large organisation.
This plugin, with an embedded and dynamically configured SimpleSamlPHP instance under the hood
Warm thanks
Thanks to the various authors and contributors to the other plugins above.
Thanks to LaTrobe university in Melbourne for sponsoring the initial creation of this plugin:
Thanks to Centre de gestion informatique de l’éducation in Luxembourg for sponsoring the user autocreation and field mapping work:
This plugin was developed by Catalyst IT Australia:
Screenshots
Contributors
$auth->requireAuth();
$attributes = $auth->getAttributes();
but I am trying to circumvent by check for isAuthenticated() in pre_loginpage_hook and/or should_login_redirect(). But the function always returns FALSE. The only way is if I preface it with requireAuth() to for a SP-to-IDP check. I cannot get access to the IDP assertion that was pushed/posted to the SP. How do I do this?
We have not tested or implemented IdP initiated login, only SP initiated. It also sounds like you might actually want SAML isPassive support? If you would like to sponsor either of these improvements please contact us.
https://www.catalyst-au.net/content/contact-us
If you can provide a patch, please make an issue / PR in github and we'll continue the conversation there.
The algorithm is currently 256 and it's easy to change manually here in the absence of a gui:
https://github.com/catalyst/moodle-auth_saml2/blob/MOODLE_33PLUS/config/authsources.php#L56
I've also logged adding the gui as a new feature here:
https://github.com/catalyst/moodle-auth_saml2/issues/162
I'm not sure where you are seeing sha1? The only place we use it directly is in the local key store, but this isn't a sensitive area and is only used to reduce the key size. For simplicity we could make this leverage the same hash used for the signature.
https://tracker.moodle.org/browse/MDLSITE-4781
Can you please raise the SLO issue with full details in github, ie is it the same as this: https://github.com/catalyst/moodle-auth_saml2/issues/138 ?
Exception - Unable to parse xml - FATAL[9]: PCDATA invalid char value 11 in "string" at line 1 on column 10466
any help on how i can tackle this is much appreciated. Thx!