shoaibali/simplesamlphp-module-auth2factor
SimpleSAMLphp module that challenges users for 2nd step, by generating a unique token/code. Currently this token is being sent to the user via email address. Future possibilities to integrate with an text message (sms) system. This module also allows a lower strength 2nd step authentication if token based challenge is not feasible. User preference is stored in the database and allows users to switch between the two.