1 files changed, 73 insertions, 6 deletions

diff --git a/internal/admin/server.go b/internal/admin/server.go
index 98400c2..05586ef 100644
--- a/internal/admin/server.go
+++ b/internal/admin/server.go
@@ -473,6 +473,7 @@ type loginLimiter struct {
 
 type loginAttempts struct {
 	failures    int
+	inflight    int
 	blockedTill time.Time
 	lastSeen    time.Time
 }
@@ -481,6 +482,66 @@ func newLoginLimiter() *loginLimiter {
 	return &loginLimiter{entries: make(map[string]loginAttempts), now: time.Now}
 }
 
+// begin atomically checks the cooldown and reserves an in-flight slot for
+// ip. Reserving at admission time closes the TOCTOU where a concurrent burst
+// all passes allow() before any of them records a failure: the number of
+// simultaneous verifications for one address is bounded by the same
+// threshold. Every successful begin must be paired with finish.
+func (l *loginLimiter) begin(ip string) bool {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	now := l.now()
+	e, ok := l.entries[ip]
+	if !ok {
+		if !l.makeRoomLocked(now) {
+			// The tracked map is full of cooling-down addresses; do not
+			// reserve (preserves the existing bounded-map behavior).
+			return true
+		}
+		e = loginAttempts{}
+	}
+	if now.Before(e.blockedTill) {
+		return false
+	}
+	if e.failures+e.inflight >= adminLoginMaxFailures {
+		return false
+	}
+	e.inflight++
+	e.lastSeen = now
+	l.entries[ip] = e
+	return true
+}
+
+// finish releases the in-flight slot reserved by begin and records the
+// outcome: success clears the address, failure advances the cooldown.
+func (l *loginLimiter) finish(ip string, ok bool) {
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	now := l.now()
+	e, tracked := l.entries[ip]
+	if !tracked {
+		return
+	}
+	if e.inflight > 0 {
+		e.inflight--
+	}
+	e.lastSeen = now
+	if ok {
+		delete(l.entries, ip)
+		return
+	}
+	if now.Before(e.blockedTill) {
+		l.entries[ip] = e
+		return
+	}
+	e.failures++
+	if e.failures >= adminLoginMaxFailures {
+		e.blockedTill = now.Add(adminLoginCooldown)
+		e.failures = 0
+	}
+	l.entries[ip] = e
+}
+
 // allow reports whether ip may attempt a login now.
 func (l *loginLimiter) allow(ip string) bool {
 	l.mu.Lock()
@@ -540,7 +601,7 @@ func (l *loginLimiter) makeRoomLocked(now time.Time) bool {
 		return true
 	}
 	for ip, e := range l.entries {
-		if e.failures == 0 && !now.Before(e.blockedTill) {
+		if e.failures == 0 && e.inflight == 0 && !now.Before(e.blockedTill) {
 			delete(l.entries, ip)
 		}
 	}
@@ -616,10 +677,12 @@ func (s *AdminServer) handleLogin(w http.ResponseWriter, r *http.Request) {
 	// to make password guessing expensive, so it must not cost a parse.
 	limiter := s.limitLogins()
 	ip := clientIP(r.RemoteAddr)
-	if !limiter.allow(ip) {
+	if !limiter.begin(ip) {
 		http.Error(w, "too many failed login attempts; try again later", http.StatusTooManyRequests)
 		return
 	}
+	loginOK := false
+	defer func() { limiter.finish(ip, loginOK) }()
 
 	// /login is registered before authMiddleware, so bound and buffer its body
 	// here before r.FormValue can parse it: without the cap a multipart POST
@@ -646,20 +709,17 @@ func (s *AdminServer) handleLogin(w http.ResponseWriter, r *http.Request) {
 	// primitive ("account=../../rooms/1"). Every other account-name entry
 	// point validates first.
 	if err := player.ValidName(account); err != nil {
-		limiter.fail(ip)
 		s.renderPage(w, r, "login.html", map[string]any{"Error": "Invalid account name or password."})
 		return
 	}
 
 	acc, err := s.accountStore.LoadAccount(account)
 	if err != nil || !player.CheckPassword(password, acc.PasswordHash) {
-		limiter.fail(ip)
 		s.renderPage(w, r, "login.html", map[string]any{"Error": "Invalid account name or password."})
 		return
 	}
 
 	if !acc.Admin {
-		limiter.fail(ip)
 		s.renderPage(w, r, "login.html", map[string]any{"Error": "Account is not authorized as admin."})
 		return
 	}
@@ -693,7 +753,7 @@ func (s *AdminServer) handleLogin(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	s.setAuthCookie(w, account)
-	limiter.succeed(ip)
+	loginOK = true
 	http.Redirect(w, r, "/", http.StatusFound)
 }
 
@@ -898,6 +958,13 @@ func (s *AdminServer) handleEntityDirs(entityType string) http.HandlerFunc {
 				failJSON(w, err.Error())
 				return
 			}
+			// Undo history stores absolute paths; re-prefix them so a later
+			// undo does not recreate the old entity directory.
+			if s.undoStack != nil {
+				oldPrefix := filepath.Join(s.dataDir, entityType, body.Dir)
+				newPrefix := filepath.Join(s.dataDir, entityType, body.NewName)
+				s.undoStack.RewritePaths(oldPrefix, newPrefix)
+			}
 			writeJSON(w, map[string]any{"ok": true, "name": body.NewName})
 		default:
 			failJSON(w, "unknown action")