Existing protection was per-IP only (login_attempts table). On a loopback
deployment everyone hits 127.0.0.1, so the per-IP counter is mostly
ornamental — the real attacker is on the same machine. Adds a second
defense layer that tracks failures per username with an exponential
backoff schedule.
Schema:
account_lockouts (username TEXT PK, failed_count INT,
locked_until DATETIME, last_attempt_at, last_attempt_ip)
Backoff after threshold (4+ failures):
1, 2, 3 failures → no lockout (grace window for typos)
4th → 60 s
5th → 5 min
6th → 15 min
7th → 1 h
8th → 6 h
9th and beyond → 24 h (capped)
Counter resets to 0 on successful login or reauth. Old non-locked rows
older than 30 days are pruned by CleanupExpired alongside the existing
sessions / audit_log / login_attempts cleanups.
Wiring:
- HandleLogin / HandleReauth both check RejectIfAccountLocked() before
touching the users table. Lockout responses are 429 with JSON body
{ error, retry_after } and a Retry-After header.
- Failed attempts are recorded against the username even when the user
doesn't exist, preventing account enumeration via differential
"is this account locked?" probes.
- PBKDF2 hash comparison was already constant-time (ConstantTimeEquals);
no change there.
Client (js/app.js):
- api() now preserves response status + body on Error so callers can
distinguish 429-lockout from other errors.
- New showLockoutCountdown(seconds) renders a live "Account locked —
try again in Xm Ys" message in #authHint, disables #loginBtn until
the countdown reaches 0, then re-enables it.
- doLogin / doUnlock both branch on err.status === 429 + retry_after
to call showLockoutCountdown instead of a generic error toast.
Known limitation: an attacker can DoS-lock arbitrary usernames by
spamming /login with that name. This is intentional — the alternative
(per-(username,IP) tracking) would let attackers enumerate accounts.
DoS-lock is acceptable; auth bypass is not.
Introduces the Delphi 12 FMX backend (PMServer) that hosts the embedded
WebView2 vault on 127.0.0.1, and a native bridge between JS and Delphi
that wires three privacy-focused features:
1. Secure clipboard
Copying a password registers the Win32 "ExcludeClipboardContentFromMonitorProcessing"
format alongside CF_UNICODETEXT, so Win+V clipboard history never sees
the value. Auto-clears after 30s via TTimer. Bridge.copySecure() in
app.js routes all password/username/secret copy paths through the
native layer when running inside the Delphi WebView2 (falls back to
navigator.clipboard for the PHP standalone).
2. Tray icon (X-to-tray when server running)
Closing the dev panel hides both the form HWND and the TFMAppClass
per-process proxy window that owns the FMX taskbar entry — the form's
HWND alone is not the taskbar-visible one in FMX (took some iteration
to discover). Tray menu: Open, Lock vault, Quit. Clipboard is force-
cleared on minimize as extra safety. First-time minimize fires a
balloon notification so the user knows the app is still running.
3. Auto-lock on Windows session lock (Win+L)
wtsapi32.dll!WTSRegisterSessionNotification on a dedicated message-only
window. On WM_WTSSESSION_CHANGE / WTS_SESSION_LOCK, the bridge calls
ExecuteJavaScript('lockVault()'). Same path used by the tray "Lock vault"
menu item.
Bridge architecture:
- JS → Delphi via cmd:// URLs intercepted in OnBeforeNavigate
(pattern lifted from DeskInsight Monaco). Currently exposes
cmd://clipboard/copy?text=...&clear=... and cmd://clipboard/clear.
- Delphi → JS via TTMSFNCWebBrowser.ExecuteJavaScript with guarded
calls (typeof check) so the bridge degrades cleanly if app.js isn't
loaded yet.
Files:
- Source/PM.Bridge.pas (new) — TSecureClipboard + TPMBridge
- UMainForm.pas/.fmx — bridge wiring, FormCloseQuery intercept, tray
callbacks (BridgeTrayRestore / BridgeLockRequest / BridgeQuit)
- js/app.js — Bridge object, 5 navigator.clipboard sites migrated to
Bridge.copySecure with PHP-compatible fallback, Bridge.onTrayRestore
handler that resets the auto-lock timer
.gitignore extended with Delphi build artifacts (*.dcu, Win32/, Win64/,
__history/, __recovery/, *.identcache, *.dsk, *.local, etc.) so source
checkouts stay clean.
Zaki