Unified login idea

Lock Screen Proxy

• A thin layer that is launched from the login manager before the desktop. It does basic lock/unlock functionality and masks the desktop’s.
• As it runs as the parent of every desktop, it can manage lock events and know what is running as whom.
• If the user locks their machine, all desktops can be told to lock. So no lock-> ctrl+alt+fN to bypass the lock.
• If the user unlocks their desktop, and then switches with ctrl+alt+fN, it can send the unlock event so they don’t have to type their password again (it has the latest lock/unlock message and can unlock if the last was an unlock and the latest message was an unlock)
• This can be used for RDP, Xen, and other things you might log in to.
• It will be session manager agnostic.

Text mode lock screen

• When VTs start up, the lock screen service is ready to lock or unlock the text mode virtual terminals too.

Windows in Linux

• Set up KVM with GPU passthrough for dedicated Windows VM.
  • When launching it, check apps GPU unbinding and re-binding efficiently.
  • If the GPU isn’t available, use a fallback.
• Make a viewer that starts with VNC, and extends/works with the lock manager from above.
• When there’s a VM with GPU, switch VNC for Looking Glass so we can play games in Windows.
• Automate session management on both sides so locking/unlocking Windows cascades to Linux sessions too.

RDP

• Lock/unlock events for RDP too.

Notes from claude

Primary Desktop Environments and Their Lock Signals

Desktop environments

• GNOME: Uses org.freedesktop.login1.Session.Lock() + org.gnome.ScreenSaver.Lock()
• KDE Plasma: Uses org.freedesktop.login1.Session.Lock() + org.freedesktop.ScreenSaver.Lock()
• XFCE: Uses org.freedesktop.ScreenSaver.Lock() through xfce4-screensaver
• Cinnamon: Uses org.freedesktop.ScreenSaver.Lock() + cinnamon-screensaver specific signals
• MATE: Uses org.freedesktop.ScreenSaver.Lock() through mate-screensaver
• LXQt: Uses org.freedesktop.ScreenSaver.Lock() through lxqt-screensaver
• Budgie: Uses GNOME’s signals (org.gnome.ScreenSaver.Lock())
• Enlightenment (E): Custom signals through enlightenment_remote
• LXDE: Uses org.freedesktop.ScreenSaver.Lock() through light-locker or xscreensaver
• Deepin DE: Uses own com.deepin.SessionManager.Lock() + freedesktop signals
• Pantheon (Elementary): Uses GNOME’s signaling system
• Unity: Uses GNOME’s signaling system (largely historical now)

Methods

• The freedesktop standard signals (most universal)
• logind signals (for systemd systems)
• DE-specific signals for complete coverage

Window Managers

• i3/Sway: Typically use external lockers (i3lock/swaylock) without direct signals
• AwesomeWM: No built-in signals, relies on external lockers
• bspwm: No built-in signals, relies on external lockers
• DWM: No built-in signals, relies on external lockers

Common External Lock Managers

• light-locker: Uses org.freedesktop.ScreenSaver.Lock()
• xscreensaver: Legacy X11 locking mechanisms + some DBus support
• i3lock: Direct X11 locking, no signals
• swaylock: Direct Wayland locking, no signals

Display Managers

• GDM (GNOME Display Manager)
• SDDM (Simple Desktop Display Manager)
• LightDM
• XDM (X Display Manager)
• LXDM
• SLiM