mod_auth_pubtkt
mod_auth_pubtkt is an open-source Web Single Sign-On (SSO) solution for Apache webservers, written by Manuel Kasper.
We provide commercial support with installing, configuring and customizing mod_auth_pubtkt, as well as developing custom login frontends and authentication database interfaces.
The open source project can be found here: https://neon1.net/mod_auth_pubtkt