Two-Factor Authentication on KDE Plasma 5 and kscreenlocker_greet

[Andrew Martin]

Hello,

I am interested in configuring two-factor authentication on KDE Plasma 5 using a 
PAM module for the second authentication factor (e.g. OTP) in addition to a
password. I have found that SDDM does not support this yet:
https://github.com/sddm/sddm/issues/784

I could use LightDM or GDM instead of SDDM for the display manager, but the
screenlocker will also need to support two-factor authentication. I read this
blog post about the architecture of the screenlocker in KDE Plasma 5:
https://blog.martin-graesslin.com/blog/2014/05/screenlocker-architecture-in-plasma-next/

Based on my testing, I do not believe that kscreenlocker_greet currently
supports displaying a message or input box for the second authentication factor
and therefore won't work with many existing two-factor authentication PAM
modules. Is this feature planned in a future release, or what alternatives are
available for two-factor screen locking on KDE (e.g. using xscreensaver)?

Thanks,

Andrew