Third triple audit (quality, performance, security). Key fixes:
- Blur padding offset: texture at (-pad,-pad) prevents edge darkening on all sides
- Wallpaper loads after lock.lock() — disk I/O no longer delays lock acquisition
- begin_verification disconnects old signal handler before registering new one
- resume_async resets failed_attempts to prevent premature exhaustion
- Unknown VerifyStatus with done=true triggers restart instead of hanging
- symlink_metadata() replaces separate is_file()+is_symlink() (TOCTOU)
- faillock_warning dead code removed, blur sigma clamped to [0,100]
- Redundant Zeroizing<Vec<u8>> removed, on_verify_status restricted to pub(crate)
- Warn logging for non-UTF-8 GECOS and avatar path errors
- Default impl for FingerprintListener, 3 new tests (47 total)
Address findings from second triple audit (quality, performance, security):
- Wrap PAM CString password in Zeroizing<CString> to wipe on drop (S-H1)
- Add check_account() for pam_acct_mgmt after fingerprint unlock,
with resume_async() to restart FP on transient failure (S-M1)
- 30s PAM timeout with generation counter to prevent stale result
interference from parallel auth attempts (S-M3)
- Downscale wallpaper to max 1920px before GPU blur, reducing work
by ~4x on 4K wallpapers (P-M1)
- exit(1) instead of return on no-monitor after lock.lock() (Q-2.1)
Close the only exploitable auth bypass: validate VerifyStatus signal sender
against fprintd's unique bus name. Fix fingerprint D-Bus lifecycle so devices
are properly released on verify-match and async restarts check the running
flag between awaits.
Security: num_msg guard in PAM callback, symlink rejection for background_path,
peek icon disabled, TOML parse errors logged, panic hook before logging.
Performance: blur and avatar textures cached across monitors, release profile
with LTO/strip.
PAM conv callback: check msg_style (password only for ECHO_OFF),
handle strdup OOM with proper cleanup, null-check PAM handle.
Fingerprint: self-wire D-Bus g-signal in start() via Rc<RefCell<>>
and connect_local — VerifyStatus signals are now actually dispatched.
VerifyStop before VerifyStart in restart_verify.
Lockscreen: password entry stays active after faillock threshold
(PAM decides lockout, not UI), use Zeroizing<String> from GTK entry.
Release builds exit(1) without ext-session-lock-v1 support.
Config: fingerprint_enabled as Option<bool> so empty user config
does not override system config.
Dead code: remove unused i18n strings and fingerprint accessors,
parameterize faillock_warning max_attempts.
Wrap raw pointer operations in explicit unsafe blocks inside
the unsafe extern "C" conv callback, as required by Rust 2024
edition. Remove unused mut binding.
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.
