moonlock/README.md
nevaforget 817a9547ad Rewrite moonlock from Python to Rust (v0.4.0)
Complete rewrite of the Wayland lockscreen from Python/PyGObject to
Rust/gtk4-rs for memory safety in security-critical PAM code and
consistency with the moonset/moongreet Rust ecosystem.

Modules: main, lockscreen, auth (PAM FFI), fingerprint (fprintd D-Bus),
config, i18n, users, power. 37 unit tests.

Security: PAM conversation callback with Zeroizing password, panic hook
that never unlocks, root check, ext-session-lock-v1 compositor policy,
absolute loginctl path, avatar symlink rejection.
2026-03-27 23:09:54 +01:00

1.6 KiB

Moonlock

A secure Wayland lockscreen with GTK4, PAM authentication and fingerprint support. Part of the Moonarch ecosystem.

Features

  • ext-session-lock-v1 — Protocol-guaranteed screen locking (compositor keeps screen locked on crash)
  • PAM authentication — Uses system PAM stack (/etc/pam.d/moonlock)
  • Fingerprint unlock — fprintd D-Bus integration (optional)
  • Multi-monitor — Lockscreen on every monitor
  • i18n — German and English (auto-detected)
  • Faillock warning — UI counter + system pam_faillock
  • Panic safety — Panic hook logs but never unlocks
  • Password wiping — Zeroize on drop

Requirements

  • GTK 4
  • gtk4-session-lock (ext-session-lock-v1 support)
  • PAM (/etc/pam.d/moonlock)
  • Optional: fprintd for fingerprint support

Building

cargo build --release

Installation

# Install binary
sudo install -Dm755 target/release/moonlock /usr/bin/moonlock

# Install PAM config
sudo install -Dm644 config/moonlock-pam /etc/pam.d/moonlock

# Optional: Install example config
sudo install -Dm644 config/moonlock.toml.example /etc/moonlock/moonlock.toml.example

Configuration

Create /etc/moonlock/moonlock.toml or ~/.config/moonlock/moonlock.toml:

background_path = "/usr/share/wallpapers/moon.jpg"
fingerprint_enabled = true

Usage

Typically launched via keybind in your Wayland compositor:

# Niri keybind example
binds {
    Mod+L { spawn "moonlock"; }
}

Development

cargo test
cargo build --release
LD_PRELOAD=/usr/lib/libgtk4-layer-shell.so ./target/release/moonlock

License

MIT