feat: add master password hint functionality

- Updated user model to include masterPasswordHint.
- Modified sync handler to return masterPasswordHint.
- Implemented password hint retrieval in public API.
- Enhanced user profile management to allow updating of password hint.
- Added UI components for displaying and editing password hint.
- Updated localization files for new password hint strings.
- Improved rate limiting for sensitive public requests.
- Adjusted database schema to accommodate master password hint.

migrations/0001_init.sql

@@ -13,6 +13,7 @@ CREATE TABLE IF NOT EXISTS users (
   id TEXT PRIMARY KEY,
   email TEXT NOT NULL UNIQUE,
   name TEXT,
+  master_password_hint TEXT,
   master_password_hash TEXT NOT NULL,
   key TEXT NOT NULL,
   private_key TEXT,

src/config/limits.ts

@@ -44,6 +44,12 @@
     // Sensitive public/auth request budget per IP per minute.
     // 敏感公开/认证接口每 IP 每分钟请求配额。
     sensitivePublicRequestsPerMinute: 30,
+    // Password hint lookup budget per IP per minute.
+    // 密码提示查询接口每 IP 每分钟请求配额。
+    passwordHintRequestsPerMinute: 1,
+    // Password hint lookup budget per IP per hour.
+    // 密码提示查询接口每 IP 每小时请求配额。
+    passwordHintRequestsPerHour: 3,
     // Register endpoint budget per IP per minute.
     // 注册接口每 IP 每分钟请求配额。
     registerRequestsPerMinute: 5,

src/handlers/accounts.ts

@@ -62,6 +62,11 @@ function normalizeRecoveryCodeInput(input: string): string {
   return String(input || '').toUpperCase().replace(/[^A-Z2-7]/g, '');
 }
 
+function normalizeMasterPasswordHint(input: string | null | undefined): string | null {
+  const normalized = String(input || '').trim();
+  return normalized ? normalized : null;
+}
+
 function jwtSecretUnsafeReason(env: Env): 'missing' | 'default' | 'too_short' | null {
   const secret = (env.JWT_SECRET || '').trim();
   if (!secret) return 'missing';
@@ -80,7 +85,7 @@ function toProfile(user: User, env: Env): ProfileResponse {
     premium: true,
     premiumFromOrganization: false,
     usesKeyConnector: false,
-    masterPasswordHint: null,
+    masterPasswordHint: user.masterPasswordHint,
     culture: 'en-US',
     twoFactorEnabled: !!user.totpSecret,
     key: user.key,
@@ -125,6 +130,7 @@ export async function handleRegister(request: Request, env: Env): Promise<Respon
     kdfMemory?: number;
     kdfParallelism?: number;
     inviteCode?: string;
+    masterPasswordHint?: string;
     keys?: {
       publicKey?: string;
       encryptedPrivateKey?: string;
@@ -144,6 +150,7 @@ export async function handleRegister(request: Request, env: Env): Promise<Respon
   const privateKey = body.keys?.encryptedPrivateKey;
   const publicKey = body.keys?.publicKey;
   const inviteCode = (body.inviteCode || '').trim();
+  const masterPasswordHint = normalizeMasterPasswordHint(body.masterPasswordHint);
 
   if (!email || !masterPasswordHash || !key) {
     return errorResponse('Email, masterPasswordHash, and key are required', 400);
@@ -160,6 +167,9 @@ export async function handleRegister(request: Request, env: Env): Promise<Respon
   if (!looksLikeEncString(privateKey)) {
     return errorResponse('encryptedPrivateKey is not a valid encrypted string', 400);
   }
+  if (masterPasswordHint && masterPasswordHint.length > 120) {
+    return errorResponse('masterPasswordHint must be 120 characters or fewer', 400);
+  }
 
   const kdfErr = validateKdfParams(body.kdf, body.kdfIterations, body.kdfMemory, body.kdfParallelism);
   if (kdfErr) return errorResponse(kdfErr, 400);
@@ -172,6 +182,7 @@ export async function handleRegister(request: Request, env: Env): Promise<Respon
     id: generateUUID(),
     email,
     name: name || email,
+    masterPasswordHint,
     masterPasswordHash: serverHash,
     key,
     privateKey,
@@ -242,6 +253,80 @@ export async function handleRegister(request: Request, env: Env): Promise<Respon
   return jsonResponse({ success: true, role: user.role }, 200);
 }
 
+// POST /api/accounts/password-hint
+export async function handleGetPasswordHint(request: Request, env: Env): Promise<Response> {
+  const storage = new StorageService(env.DB);
+  const clientIdentifier = getClientIdentifier(request);
+  if (!clientIdentifier) {
+    return errorResponse('Client IP is required', 403);
+  }
+
+  let body: { email?: string };
+  try {
+    body = await request.json();
+  } catch {
+    return errorResponse('Invalid JSON', 400);
+  }
+
+  const email = String(body.email || '').trim().toLowerCase();
+  if (!email) {
+    return errorResponse('Email is required', 400);
+  }
+
+  const rateLimit = new RateLimitService(env.DB);
+  const minuteBudget = await rateLimit.consumeBudgetWithWindow(
+    `${clientIdentifier}:password-hint`,
+    LIMITS.rateLimit.passwordHintRequestsPerMinute,
+    60
+  );
+  if (!minuteBudget.allowed) {
+    return new Response(
+      JSON.stringify({
+        error: 'Too many requests',
+        error_description: `Rate limit exceeded. Try again in ${minuteBudget.retryAfterSeconds || 60} seconds.`,
+      }),
+      {
+        status: 429,
+        headers: {
+          'Content-Type': 'application/json',
+          'Retry-After': String(minuteBudget.retryAfterSeconds || 60),
+          'X-RateLimit-Remaining': '0',
+        },
+      }
+    );
+  }
+
+  const hourlyBudget = await rateLimit.consumeBudgetWithWindow(
+    `${clientIdentifier}:password-hint-hour`,
+    LIMITS.rateLimit.passwordHintRequestsPerHour,
+    60 * 60
+  );
+  if (!hourlyBudget.allowed) {
+    return new Response(
+      JSON.stringify({
+        error: 'Too many requests',
+        error_description: `Rate limit exceeded. Try again in ${hourlyBudget.retryAfterSeconds || 3600} seconds.`,
+      }),
+      {
+        status: 429,
+        headers: {
+          'Content-Type': 'application/json',
+          'Retry-After': String(hourlyBudget.retryAfterSeconds || 3600),
+          'X-RateLimit-Remaining': '0',
+        },
+      }
+    );
+  }
+
+  const user = await storage.getUser(email);
+  const hint = user?.status === 'active' ? normalizeMasterPasswordHint(user.masterPasswordHint) : null;
+  return jsonResponse({
+    object: 'passwordHint',
+    hasHint: !!hint,
+    masterPasswordHint: hint,
+  });
+}
+
 // GET /api/accounts/profile
 export async function handleGetProfile(request: Request, env: Env, userId: string): Promise<Response> {
   void request;
@@ -251,6 +336,33 @@ export async function handleGetProfile(request: Request, env: Env, userId: strin
   return jsonResponse(toProfile(user, env));
 }
 
+// PUT /api/accounts/profile
+export async function handleUpdateProfile(request: Request, env: Env, userId: string): Promise<Response> {
+  const storage = new StorageService(env.DB);
+  const user = await storage.getUserById(userId);
+  if (!user) return errorResponse('User not found', 404);
+
+  let body: {
+    masterPasswordHint?: string | null;
+  };
+  try {
+    body = await request.json();
+  } catch {
+    return errorResponse('Invalid JSON', 400);
+  }
+
+  const masterPasswordHint = normalizeMasterPasswordHint(body.masterPasswordHint);
+  if (masterPasswordHint && masterPasswordHint.length > 120) {
+    return errorResponse('masterPasswordHint must be 120 characters or fewer', 400);
+  }
+
+  user.masterPasswordHint = masterPasswordHint;
+  user.updatedAt = new Date().toISOString();
+  await storage.saveUser(user);
+
+  return jsonResponse(toProfile(user, env));
+}
+
 // POST /api/accounts/keys
 export async function handleSetKeys(request: Request, env: Env, userId: string): Promise<Response> {
   const storage = new StorageService(env.DB);

src/handlers/sync.ts

@@ -135,7 +135,7 @@ export async function handleSync(request: Request, env: Env, userId: string): Pr
     premium: true,
     premiumFromOrganization: false,
     usesKeyConnector: false,
-    masterPasswordHint: null,
+    masterPasswordHint: user.masterPasswordHint,
     culture: 'en-US',
     twoFactorEnabled: !!user.totpSecret,
     key: user.key,

src/index.ts

@@ -32,6 +32,10 @@ function injectBootstrapIntoHtml(html: string, env: Env): string {
   return `${script}${html}`;
 }
 
+function responseStatusCannotHaveBody(status: number): boolean {
+  return status === 101 || status === 204 || status === 205 || status === 304;
+}
+
 async function maybeServeAsset(request: Request, env: Env): Promise<Response | null> {
   if (!env.ASSETS) return null;
   if (request.method !== 'GET' && request.method !== 'HEAD') return null;
@@ -40,7 +44,11 @@ async function maybeServeAsset(request: Request, env: Env): Promise<Response | n
 
   const assetResponse = await env.ASSETS.fetch(request);
   const contentType = String(assetResponse.headers.get('Content-Type') || '').toLowerCase();
-  if (request.method === 'GET' && contentType.includes('text/html')) {
+  if (
+    request.method === 'GET' &&
+    contentType.includes('text/html') &&
+    !responseStatusCannotHaveBody(assetResponse.status)
+  ) {
     const html = await assetResponse.text();
     const injected = injectBootstrapIntoHtml(html, env);
     return new Response(injected, {

src/router-authenticated.ts

@@ -2,6 +2,7 @@ import type { Env, User } from './types';
 import { errorResponse, jsonResponse } from './utils/response';
 import {
   handleGetProfile,
+  handleUpdateProfile,
   handleSetKeys,
   handleGetRevisionDate,
   handleVerifyPassword,
@@ -79,6 +80,7 @@ export async function handleAuthenticatedRoute(
 
   if (path === '/api/accounts/profile') {
     if (method === 'GET') return handleGetProfile(request, env, userId);
+    if (method === 'PUT') return handleUpdateProfile(request, env, userId);
     return errorResponse('Method not allowed', 405);
   }
 

src/router-public.ts

@@ -11,6 +11,7 @@ import { handleKnownDevice } from './handlers/devices';
 import { handleToken, handlePrelogin, handleRevocation } from './handlers/identity';
 import {
   handleRegister,
+  handleGetPasswordHint,
   handleRecoverTwoFactor,
 } from './handlers/accounts';
 import { handlePublicDownloadAttachment } from './handlers/attachments';
@@ -252,6 +253,18 @@ export async function handlePublicRoute(
     return handleRecoverTwoFactor(request, env);
   }
 
+  if (path === '/api/accounts/password-hint' && method === 'POST') {
+    const blocked = await enforcePublicRateLimit('public-sensitive', LIMITS.rateLimit.sensitivePublicRequestsPerMinute);
+    if (blocked) return blocked;
+    if (!isSameOriginWriteRequest(request)) {
+      return new Response(JSON.stringify({ error: 'Forbidden origin' }), {
+        status: 403,
+        headers: { 'Content-Type': 'application/json' },
+      });
+    }
+    return handleGetPasswordHint(request, env);
+  }
+
   if ((path === '/config' || path === '/api/config') && method === 'GET') {
     const blocked = await enforcePublicRateLimit('public-read', LIMITS.rateLimit.publicReadRequestsPerMinute);
     if (blocked) return blocked;

src/services/backup-archive.ts

@@ -370,7 +370,7 @@ export async function buildBackupArchive(env: Env, date: Date = new Date()): Pro
   const encoder = new TextEncoder();
   const [configRows, userRows, revisionRows, folderRows, cipherRows, attachmentRows, sendRows] = await Promise.all([
     queryRows(env.DB, 'SELECT key, value FROM config ORDER BY key ASC'),
-    queryRows(env.DB, 'SELECT id, email, name, master_password_hash, key, private_key, public_key, kdf_type, kdf_iterations, kdf_memory, kdf_parallelism, security_stamp, role, status, totp_secret, totp_recovery_code, created_at, updated_at FROM users ORDER BY created_at ASC'),
+    queryRows(env.DB, 'SELECT id, email, name, master_password_hint, master_password_hash, key, private_key, public_key, kdf_type, kdf_iterations, kdf_memory, kdf_parallelism, security_stamp, role, status, totp_secret, totp_recovery_code, created_at, updated_at FROM users ORDER BY created_at ASC'),
     queryRows(env.DB, 'SELECT user_id, revision_date FROM user_revisions ORDER BY user_id ASC'),
     queryRows(env.DB, 'SELECT id, user_id, name, created_at, updated_at FROM folders ORDER BY created_at ASC'),
     queryRows(env.DB, 'SELECT id, user_id, type, folder_id, name, notes, favorite, data, reprompt, key, created_at, updated_at, deleted_at FROM ciphers ORDER BY created_at ASC'),

src/services/backup-import.ts

@@ -270,7 +270,7 @@ async function importBackupRows(db: D1Database, payload: BackupPayload['db']): P
     ...buildInsertStatements(
       db,
       'users',
-      ['id', 'email', 'name', 'master_password_hash', 'key', 'private_key', 'public_key', 'kdf_type', 'kdf_iterations', 'kdf_memory', 'kdf_parallelism', 'security_stamp', 'role', 'status', 'totp_secret', 'totp_recovery_code', 'created_at', 'updated_at'],
+      ['id', 'email', 'name', 'master_password_hint', 'master_password_hash', 'key', 'private_key', 'public_key', 'kdf_type', 'kdf_iterations', 'kdf_memory', 'kdf_parallelism', 'security_stamp', 'role', 'status', 'totp_secret', 'totp_recovery_code', 'created_at', 'updated_at'],
       payload.users || []
     ),
     ...buildInsertStatements(db, 'user_revisions', ['user_id', 'revision_date'], payload.user_revisions || [], true),

src/services/ratelimit.ts

@@ -184,6 +184,14 @@ export class RateLimitService {
   ): Promise<{ allowed: boolean; remaining: number; retryAfterSeconds?: number }> {
     return this.consumeFixedWindowBudget(identifier, maxRequests, CONFIG.API_WINDOW_SECONDS);
   }
+
+  async consumeBudgetWithWindow(
+    identifier: string,
+    maxRequests: number,
+    windowSeconds: number
+  ): Promise<{ allowed: boolean; remaining: number; retryAfterSeconds?: number }> {
+    return this.consumeFixedWindowBudget(identifier, maxRequests, windowSeconds);
+  }
 }
 
 function parseIpv4Octets(input: string): number[] | null {

src/services/storage-schema.ts

@@ -3,10 +3,11 @@
 // Any new table/column/index must be added to both places together.
 const SCHEMA_STATEMENTS: readonly string[] = [
   'CREATE TABLE IF NOT EXISTS users (' +
-  'id TEXT PRIMARY KEY, email TEXT NOT NULL UNIQUE, name TEXT, master_password_hash TEXT NOT NULL, ' +
+  'id TEXT PRIMARY KEY, email TEXT NOT NULL UNIQUE, name TEXT, master_password_hint TEXT, master_password_hash TEXT NOT NULL, ' +
   'key TEXT NOT NULL, private_key TEXT, public_key TEXT, kdf_type INTEGER NOT NULL, ' +
   'kdf_iterations INTEGER NOT NULL, kdf_memory INTEGER, kdf_parallelism INTEGER, ' +
   'security_stamp TEXT NOT NULL, role TEXT NOT NULL DEFAULT \'user\', status TEXT NOT NULL DEFAULT \'active\', totp_secret TEXT, totp_recovery_code TEXT, created_at TEXT NOT NULL, updated_at TEXT NOT NULL)',
+  'ALTER TABLE users ADD COLUMN master_password_hint TEXT',
   'ALTER TABLE users ADD COLUMN role TEXT NOT NULL DEFAULT \'user\'',
   'ALTER TABLE users ADD COLUMN status TEXT NOT NULL DEFAULT \'active\'',
   'ALTER TABLE users ADD COLUMN totp_secret TEXT',

src/services/storage-user-repo.ts

@@ -7,6 +7,7 @@ function mapUserRow(row: any): User {
     id: row.id,
     email: row.email,
     name: row.name,
+    masterPasswordHint: row.master_password_hint ?? null,
     masterPasswordHash: row.master_password_hash,
     key: row.key,
     privateKey: row.private_key,
@@ -28,7 +29,7 @@ function mapUserRow(row: any): User {
 export async function getUser(db: D1Database, email: string): Promise<User | null> {
   const row = await db
     .prepare(
-      'SELECT id, email, name, master_password_hash, key, private_key, public_key, kdf_type, kdf_iterations, kdf_memory, kdf_parallelism, security_stamp, role, status, totp_secret, totp_recovery_code, created_at, updated_at FROM users WHERE email = ?'
+      'SELECT id, email, name, master_password_hint, master_password_hash, key, private_key, public_key, kdf_type, kdf_iterations, kdf_memory, kdf_parallelism, security_stamp, role, status, totp_secret, totp_recovery_code, created_at, updated_at FROM users WHERE email = ?'
     )
     .bind(email.toLowerCase())
     .first<any>();
@@ -39,7 +40,7 @@ export async function getUser(db: D1Database, email: string): Promise<User | nul
 export async function getUserById(db: D1Database, id: string): Promise<User | null> {
   const row = await db
     .prepare(
-      'SELECT id, email, name, master_password_hash, key, private_key, public_key, kdf_type, kdf_iterations, kdf_memory, kdf_parallelism, security_stamp, role, status, totp_secret, totp_recovery_code, created_at, updated_at FROM users WHERE id = ?'
+      'SELECT id, email, name, master_password_hint, master_password_hash, key, private_key, public_key, kdf_type, kdf_iterations, kdf_memory, kdf_parallelism, security_stamp, role, status, totp_secret, totp_recovery_code, created_at, updated_at FROM users WHERE id = ?'
     )
     .bind(id)
     .first<any>();
@@ -55,7 +56,7 @@ export async function getUserCount(db: D1Database): Promise<number> {
 export async function getAllUsers(db: D1Database): Promise<User[]> {
   const res = await db
     .prepare(
-      'SELECT id, email, name, master_password_hash, key, private_key, public_key, kdf_type, kdf_iterations, kdf_memory, kdf_parallelism, security_stamp, role, status, totp_secret, totp_recovery_code, created_at, updated_at FROM users ORDER BY created_at ASC'
+      'SELECT id, email, name, master_password_hint, master_password_hash, key, private_key, public_key, kdf_type, kdf_iterations, kdf_memory, kdf_parallelism, security_stamp, role, status, totp_secret, totp_recovery_code, created_at, updated_at FROM users ORDER BY created_at ASC'
     )
     .all<any>();
   return (res.results || []).map((row) => mapUserRow(row));
@@ -64,10 +65,10 @@ export async function getAllUsers(db: D1Database): Promise<User[]> {
 export async function saveUser(db: D1Database, safeBind: SafeBind, user: User): Promise<void> {
   const email = user.email.toLowerCase();
   const stmt = db.prepare(
-    'INSERT INTO users(id, email, name, master_password_hash, key, private_key, public_key, kdf_type, kdf_iterations, kdf_memory, kdf_parallelism, security_stamp, role, status, totp_secret, totp_recovery_code, created_at, updated_at) ' +
-    'VALUES(?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?) ' +
+    'INSERT INTO users(id, email, name, master_password_hint, master_password_hash, key, private_key, public_key, kdf_type, kdf_iterations, kdf_memory, kdf_parallelism, security_stamp, role, status, totp_secret, totp_recovery_code, created_at, updated_at) ' +
+    'VALUES(?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?) ' +
     'ON CONFLICT(id) DO UPDATE SET ' +
-    'email=excluded.email, name=excluded.name, master_password_hash=excluded.master_password_hash, key=excluded.key, private_key=excluded.private_key, public_key=excluded.public_key, ' +
+    'email=excluded.email, name=excluded.name, master_password_hint=excluded.master_password_hint, master_password_hash=excluded.master_password_hash, key=excluded.key, private_key=excluded.private_key, public_key=excluded.public_key, ' +
     'kdf_type=excluded.kdf_type, kdf_iterations=excluded.kdf_iterations, kdf_memory=excluded.kdf_memory, kdf_parallelism=excluded.kdf_parallelism, security_stamp=excluded.security_stamp, role=excluded.role, status=excluded.status, totp_secret=excluded.totp_secret, totp_recovery_code=excluded.totp_recovery_code, updated_at=excluded.updated_at'
   );
   await safeBind(
@@ -75,6 +76,7 @@ export async function saveUser(db: D1Database, safeBind: SafeBind, user: User):
     user.id,
     email,
     user.name,
+    user.masterPasswordHint,
     user.masterPasswordHash,
     user.key,
     user.privateKey,
@@ -100,8 +102,8 @@ export async function createUser(db: D1Database, safeBind: SafeBind, user: User)
 export async function createFirstUser(db: D1Database, safeBind: SafeBind, user: User): Promise<boolean> {
   const email = user.email.toLowerCase();
   const stmt = db.prepare(
-    'INSERT INTO users(id, email, name, master_password_hash, key, private_key, public_key, kdf_type, kdf_iterations, kdf_memory, kdf_parallelism, security_stamp, role, status, totp_secret, totp_recovery_code, created_at, updated_at) ' +
-    'SELECT ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ? ' +
+    'INSERT INTO users(id, email, name, master_password_hint, master_password_hash, key, private_key, public_key, kdf_type, kdf_iterations, kdf_memory, kdf_parallelism, security_stamp, role, status, totp_secret, totp_recovery_code, created_at, updated_at) ' +
+    'SELECT ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ? ' +
     'WHERE NOT EXISTS (SELECT 1 FROM users LIMIT 1)'
   );
   const result = await safeBind(
@@ -109,6 +111,7 @@ export async function createFirstUser(db: D1Database, safeBind: SafeBind, user:
     user.id,
     email,
     user.name,
+    user.masterPasswordHint,
     user.masterPasswordHash,
     user.key,
     user.privateKey,

src/services/storage.ts

@@ -102,7 +102,7 @@ import {
 
 const TWO_FACTOR_REMEMBER_TTL_MS = 30 * 24 * 60 * 60 * 1000;
 const STORAGE_SCHEMA_VERSION_KEY = 'schema.version';
-const STORAGE_SCHEMA_VERSION = '2026-03-18.1';
+const STORAGE_SCHEMA_VERSION = '2026-03-19.1';
 
 // D1-backed storage.
 // Contract:

src/types/index.ts

@@ -35,6 +35,7 @@ export interface User {
   id: string;
   email: string;
   name: string | null;
+  masterPasswordHint: string | null;
   masterPasswordHash: string;
   key: string;
   privateKey: string | null;

webapp/src/App.tsx

@@ -11,6 +11,7 @@ import {
   createAuthedFetch,
   getAuthorizedDevices,
   getCurrentDeviceIdentifier,
+  getPasswordHint,
   getTotpStatus,
   saveSession,
 } from '@/lib/api/auth';
@@ -78,8 +79,18 @@ export default function App() {
     email: '',
     password: '',
     password2: '',
+    passwordHint: '',
     inviteCode: initialInviteCode,
   });
+  const [loginHintState, setLoginHintState] = useState<{
+    email: string;
+    loading: boolean;
+    hint: string | null;
+  }>({
+    email: '',
+    loading: false,
+    hint: null,
+  });
   const [inviteCodeFromUrl, setInviteCodeFromUrl] = useState(initialInviteCode);
   const [unlockPassword, setUnlockPassword] = useState('');
   const [pendingTotp, setPendingTotp] = useState<PendingTotp | null>(null);
@@ -131,6 +142,15 @@ export default function App() {
     setRegisterValues((prev) => (prev.inviteCode === inviteCodeFromUrl ? prev : { ...prev, inviteCode: inviteCodeFromUrl }));
   }, [inviteCodeFromUrl]);
 
+  useEffect(() => {
+    const normalizedEmail = loginValues.email.trim().toLowerCase();
+    setLoginHintState((prev) => (
+      prev.email && prev.email !== normalizedEmail
+        ? { email: '', loading: false, hint: null }
+        : prev
+    ));
+  }, [loginValues.email]);
+
   useEffect(() => {
     if (!inviteCodeFromUrl) return;
     if (phase === 'locked' || phase === 'app') return;
@@ -200,7 +220,7 @@ export default function App() {
   useEffect(() => {
     let mounted = true;
     (async () => {
-      const boot = await bootstrapAppSession();
+      const boot = await bootstrapAppSession(initialBootstrap);
       if (!mounted) return;
       setDefaultKdfIterations(boot.defaultKdfIterations);
       setJwtWarning(boot.jwtWarning);
@@ -212,7 +232,7 @@ export default function App() {
     return () => {
       mounted = false;
     };
-  }, []);
+  }, [initialBootstrap]);
 
   async function finalizeLogin(login: CompletedLogin) {
     setSession(login.session);
@@ -322,6 +342,7 @@ export default function App() {
         email: registerValues.email,
         name: registerValues.name,
         password: registerValues.password,
+        masterPasswordHint: registerValues.passwordHint,
         inviteCode: registerValues.inviteCode,
         fallbackIterations: defaultKdfIterations,
       });
@@ -338,6 +359,56 @@ export default function App() {
     }
   }
 
+  function openPasswordHintDialog(hint: string | null) {
+    setConfirm({
+      title: t('txt_password_hint'),
+      message: hint || t('txt_password_hint_not_set'),
+      showIcon: false,
+      confirmText: t('txt_close'),
+      hideCancel: true,
+      onConfirm: () => setConfirm(null),
+    });
+  }
+
+  async function handleTogglePasswordHint() {
+    if (pendingAuthAction) return;
+    const email = loginValues.email.trim().toLowerCase();
+    if (!email) return;
+
+    if (loginHintState.email === email && !loginHintState.loading) {
+      openPasswordHintDialog(loginHintState.hint);
+      return;
+    }
+
+    setLoginHintState({
+      email,
+      loading: true,
+      hint: null,
+    });
+
+    try {
+      const result = await getPasswordHint(email);
+      openPasswordHintDialog(result.masterPasswordHint);
+      setLoginHintState({
+        email,
+        loading: false,
+        hint: result.masterPasswordHint,
+      });
+    } catch (error) {
+      setLoginHintState({
+        email: '',
+        loading: false,
+        hint: null,
+      });
+      pushToast('error', error instanceof Error ? error.message : t('txt_password_hint_load_failed'));
+    }
+  }
+
+  function handleShowLockedPasswordHint() {
+    if (pendingAuthAction) return;
+    openPasswordHintDialog(profile?.masterPasswordHint ?? null);
+  }
+
   async function handleUnlock() {
     if (pendingAuthAction) return;
     if (!session || !profile) return;
@@ -804,6 +875,7 @@ export default function App() {
     },
     onLogoutNow: logoutNow,
     onNotify: pushToast,
+    onProfileUpdated: setProfile,
     onSetConfirm: setConfirm,
     refetchTotpStatus: totpStatusQuery.refetch,
     refetchAuthorizedDevices: authorizedDevicesQuery.refetch,
@@ -923,6 +995,7 @@ export default function App() {
     uploadingSendFileName: vaultSendActions.uploadingSendFileName,
     sendUploadPercent: vaultSendActions.sendUploadPercent,
     onChangePassword: accountSecurityActions.changePassword,
+    onSavePasswordHint: accountSecurityActions.savePasswordHint,
     onEnableTotp: async (secret: string, token: string) => {
       await accountSecurityActions.enableTotp(secret, token);
       await totpStatusQuery.refetch();
@@ -992,6 +1065,7 @@ export default function App() {
           registerValues={registerValues}
           unlockPassword={unlockPassword}
           emailForLock={profile?.email || session?.email || ''}
+          loginHintLoading={loginHintState.loading}
           onChangeLogin={setLoginValues}
           onChangeRegister={setRegisterValues}
           onChangeUnlock={setUnlockPassword}
@@ -1010,12 +1084,14 @@ export default function App() {
             navigate('/register');
           }}
           onLogout={logoutNow}
+          onTogglePasswordHint={() => void handleTogglePasswordHint()}
+          onShowLockedPasswordHint={handleShowLockedPasswordHint}
         />
         <AppGlobalOverlays
           toasts={toasts}
           onCloseToast={removeToast}
-          confirm={null}
-          onCancelConfirm={() => {}}
+          confirm={confirm}
+          onCancelConfirm={() => setConfirm(null)}
           pendingTotpOpen={!!pendingTotp}
           totpCode={totpCode}
           rememberDevice={rememberDevice}

webapp/src/components/AppGlobalOverlays.tsx

@@ -8,6 +8,9 @@ export interface AppConfirmState {
   message: string;
   danger?: boolean;
   showIcon?: boolean;
+  confirmText?: string;
+  cancelText?: string;
+  hideCancel?: boolean;
   onConfirm: () => void;
 }
 
@@ -40,6 +43,9 @@ export default function AppGlobalOverlays(props: AppGlobalOverlaysProps) {
         message={props.confirm?.message || ''}
         danger={props.confirm?.danger}
         showIcon={props.confirm?.showIcon}
+        confirmText={props.confirm?.confirmText}
+        cancelText={props.confirm?.cancelText}
+        hideCancel={props.confirm?.hideCancel}
         onConfirm={() => props.confirm?.onConfirm()}
         onCancel={props.onCancelConfirm}
       />

webapp/src/components/AppMainRoutes.tsx

@@ -77,6 +77,7 @@ export interface AppMainRoutesProps {
   uploadingSendFileName: string;
   sendUploadPercent: number | null;
   onChangePassword: (currentPassword: string, nextPassword: string, nextPassword2: string) => Promise<void>;
+  onSavePasswordHint: (masterPasswordHint: string) => Promise<void>;
   onEnableTotp: (secret: string, token: string) => Promise<void>;
   onOpenDisableTotp: () => void;
   onGetRecoveryCode: (masterPassword: string) => Promise<string>;
@@ -198,6 +199,7 @@ export default function AppMainRoutes(props: AppMainRoutesProps) {
                 profile={props.profile}
                 totpEnabled={props.totpEnabled}
                 onChangePassword={props.onChangePassword}
+                onSavePasswordHint={props.onSavePasswordHint}
                 onEnableTotp={props.onEnableTotp}
                 onOpenDisableTotp={props.onOpenDisableTotp}
                 onGetRecoveryCode={props.onGetRecoveryCode}

webapp/src/components/AuthViews.tsx

@@ -13,6 +13,7 @@ interface RegisterValues {
   email: string;
   password: string;
   password2: string;
+  passwordHint: string;
   inviteCode: string;
 }
 
@@ -24,6 +25,7 @@ interface AuthViewsProps {
   registerValues: RegisterValues;
   unlockPassword: string;
   emailForLock: string;
+  loginHintLoading: boolean;
   onChangeLogin: (next: LoginValues) => void;
   onChangeRegister: (next: RegisterValues) => void;
   onChangeUnlock: (password: string) => void;
@@ -33,6 +35,8 @@ interface AuthViewsProps {
   onGotoLogin: () => void;
   onGotoRegister: () => void;
   onLogout: () => void;
+  onTogglePasswordHint: () => void;
+  onShowLockedPasswordHint: () => void;
 }
 
 function PasswordField(props: {
@@ -87,6 +91,17 @@ export default function AuthViews(props: AuthViewsProps) {
               autoComplete="current-password"
               onInput={props.onChangeUnlock}
             />
+            <div className="auth-support-row">
+              <span />
+              <button
+                type="button"
+                className="auth-link-btn"
+                onClick={props.onShowLockedPasswordHint}
+                disabled={unlockBusy}
+              >
+                {t('txt_show_password_hint')}
+              </button>
+            </div>
             <button type="submit" className="btn btn-primary full" disabled={unlockBusy || !props.unlockReady}>
               <Unlock size={16} className="btn-icon" />
               {unlockBusy ? t('txt_unlocking') : t('txt_unlock')}
@@ -147,6 +162,18 @@ export default function AuthViews(props: AuthViewsProps) {
               autoComplete="new-password"
               onInput={(v) => props.onChangeRegister({ ...props.registerValues, password2: v })}
             />
+            <label className="field">
+              <span>{t('txt_password_hint_optional')}</span>
+              <input
+                className="input"
+                maxLength={120}
+                value={props.registerValues.passwordHint}
+                placeholder={t('txt_password_hint_register_placeholder')}
+                onInput={(e) =>
+                  props.onChangeRegister({ ...props.registerValues, passwordHint: (e.currentTarget as HTMLInputElement).value })
+                }
+              />
+            </label>
             <label className="field">
               <span>{t('txt_invite_code_optional')}</span>
               <input
@@ -199,6 +226,19 @@ export default function AuthViews(props: AuthViewsProps) {
             onInput={(v) => props.onChangeLogin({ ...props.loginValues, password: v })}
             autoFocus
           />
+          <div className="auth-support-row">
+            <span />
+            <button
+              type="button"
+              className="auth-link-btn"
+              onClick={props.onTogglePasswordHint}
+              disabled={loginBusy || !props.loginValues.email.trim()}
+            >
+              {props.loginHintLoading
+                ? t('txt_loading_password_hint')
+                : t('txt_show_password_hint')}
+            </button>
+          </div>
           <button type="submit" className="btn btn-primary full" disabled={loginBusy}>
             <LogIn size={16} className="btn-icon" />
             {loginBusy ? t('txt_logging_in') : t('txt_log_in')}

webapp/src/components/ConfirmDialog.tsx

@@ -10,6 +10,7 @@ interface ConfirmDialogProps {
   confirmText?: string;
   cancelText?: string;
   danger?: boolean;
+  hideCancel?: boolean;
   onConfirm: () => void;
   onCancel: () => void;
   children?: ComponentChildren;
@@ -37,10 +38,12 @@ export default function ConfirmDialog(props: ConfirmDialogProps) {
           <Check size={14} className="btn-icon" />
           {props.confirmText || t('txt_yes')}
         </button>
-        <button type="button" className="btn btn-secondary dialog-btn" onClick={props.onCancel}>
-          <X size={14} className="btn-icon" />
-          {props.cancelText || t('txt_no')}
-        </button>
+        {!props.hideCancel && (
+          <button type="button" className="btn btn-secondary dialog-btn" onClick={props.onCancel}>
+            <X size={14} className="btn-icon" />
+            {props.cancelText || t('txt_no')}
+          </button>
+        )}
         {props.afterActions}
       </form>
     </div>

webapp/src/components/SettingsPage.tsx

@@ -9,6 +9,7 @@ interface SettingsPageProps {
   profile: Profile;
   totpEnabled: boolean;
   onChangePassword: (currentPassword: string, nextPassword: string, nextPassword2: string) => Promise<void>;
+  onSavePasswordHint: (masterPasswordHint: string) => Promise<void>;
   onEnableTotp: (secret: string, token: string) => Promise<void>;
   onOpenDisableTotp: () => void;
   onGetRecoveryCode: (masterPassword: string) => Promise<string>;
@@ -40,6 +41,7 @@ export default function SettingsPage(props: SettingsPageProps) {
   const [currentPassword, setCurrentPassword] = useState('');
   const [newPassword, setNewPassword] = useState('');
   const [newPassword2, setNewPassword2] = useState('');
+  const [passwordHint, setPasswordHint] = useState(props.profile.masterPasswordHint || '');
   const [secret, setSecret] = useState(() => localStorage.getItem(totpSecretStorageKey) || randomBase32Secret(32));
   const [token, setToken] = useState('');
   const [totpLocked, setTotpLocked] = useState(props.totpEnabled);
@@ -54,6 +56,10 @@ export default function SettingsPage(props: SettingsPageProps) {
     setTotpLocked(true);
   }, [props.totpEnabled]);
 
+  useEffect(() => {
+    setPasswordHint(props.profile.masterPasswordHint || '');
+  }, [props.profile.masterPasswordHint]);
+
   const qrDataUrl = useMemo(() => {
     const qr = qrcode(0, 'M');
     qr.addData(buildOtpUri(props.profile.email, secret));
@@ -81,6 +87,28 @@ export default function SettingsPage(props: SettingsPageProps) {
 
   return (
     <div className="stack">
+      <section className="card">
+        <h3>{t('txt_profile')}</h3>
+        <label className="field">
+          <span>{t('txt_password_hint_optional')}</span>
+          <input
+            className="input"
+            maxLength={120}
+            value={passwordHint}
+            placeholder={t('txt_password_hint_placeholder')}
+            onInput={(e) => setPasswordHint((e.currentTarget as HTMLInputElement).value)}
+          />
+          <div className="field-help">{t('txt_password_hint_register_help')}</div>
+        </label>
+        <button
+          type="button"
+          className="btn btn-secondary"
+          onClick={() => void props.onSavePasswordHint(passwordHint)}
+        >
+          {t('txt_save_profile')}
+        </button>
+      </section>
+
       <section className="card">
         <h3>{t('txt_change_master_password')}</h3>
         <label className="field">

webapp/src/hooks/useAccountSecurityActions.ts

@@ -9,6 +9,7 @@ import {
   revokeAuthorizedDeviceTrust,
   revokeAllAuthorizedDeviceTrust,
   setTotp,
+  updateProfile,
 } from '@/lib/api/auth';
 import { t } from '@/lib/i18n';
 import type { AppConfirmState } from '@/components/AppGlobalOverlays';
@@ -25,6 +26,7 @@ interface UseAccountSecurityActionsOptions {
   clearDisableTotpDialog: () => void;
   onLogoutNow: () => void;
   onNotify: Notify;
+  onProfileUpdated: (profile: Profile) => void;
   onSetConfirm: (next: AppConfirmState | null) => void;
   refetchTotpStatus: () => Promise<unknown>;
   refetchAuthorizedDevices: () => Promise<unknown>;
@@ -39,6 +41,7 @@ export default function useAccountSecurityActions(options: UseAccountSecurityAct
     clearDisableTotpDialog,
     onLogoutNow,
     onNotify,
+    onProfileUpdated,
     onSetConfirm,
     refetchTotpStatus,
     refetchAuthorizedDevices,
@@ -85,6 +88,22 @@ export default function useAccountSecurityActions(options: UseAccountSecurityAct
         });
       },
 
+      async savePasswordHint(masterPasswordHint: string) {
+        if (!profile) return;
+        const normalized = String(masterPasswordHint || '').trim();
+        if (normalized.length > 120) {
+          onNotify('error', t('txt_password_hint_too_long'));
+          return;
+        }
+        try {
+          const nextProfile = await updateProfile(authedFetch, { masterPasswordHint: normalized });
+          onProfileUpdated(nextProfile);
+          onNotify('success', t('txt_profile_updated'));
+        } catch (error) {
+          onNotify('error', error instanceof Error ? error.message : t('txt_save_profile_failed'));
+        }
+      },
+
       async enableTotp(secret: string, token: string) {
         if (!secret.trim() || !token.trim()) {
           const error = new Error(t('txt_secret_and_code_are_required'));
@@ -208,6 +227,7 @@ export default function useAccountSecurityActions(options: UseAccountSecurityAct
       disableTotpPassword,
       onLogoutNow,
       onNotify,
+      onProfileUpdated,
       onSetConfirm,
       profile,
       refetchAuthorizedDevices,

webapp/src/lib/api/auth.ts

@@ -201,11 +201,12 @@ export async function registerAccount(args: {
   email: string;
   name: string;
   password: string;
+  masterPasswordHint?: string;
   inviteCode?: string;
   fallbackIterations: number;
 }): Promise<{ ok: true } | { ok: false; message: string }> {
   try {
-    const { email, name, password, inviteCode, fallbackIterations } = args;
+    const { email, name, password, masterPasswordHint, inviteCode, fallbackIterations } = args;
     const masterKey = await pbkdf2(password, email, fallbackIterations, 32);
     const masterHash = await pbkdf2(masterKey, password, 1, 32);
     const encKey = await hkdfExpand(masterKey, 'enc', 32);
@@ -233,6 +234,7 @@ export async function registerAccount(args: {
       body: JSON.stringify({
         email: email.toLowerCase(),
         name,
+        masterPasswordHint: String(masterPasswordHint || '').trim() || undefined,
         masterPasswordHash: bytesToBase64(masterHash),
         key: encryptedVaultKey,
         kdf: 0,
@@ -255,6 +257,20 @@ export async function registerAccount(args: {
   }
 }
 
+export async function getPasswordHint(email: string): Promise<{ masterPasswordHint: string | null }> {
+  const resp = await fetch('/api/accounts/password-hint', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ email: email.trim().toLowerCase() }),
+  });
+  if (!resp.ok) {
+    const body = await parseJson<TokenError>(resp);
+    throw new Error(body?.error_description || body?.error || 'Failed to load password hint');
+  }
+  const body = (await parseJson<{ masterPasswordHint?: string | null }>(resp)) || {};
+  return { masterPasswordHint: body.masterPasswordHint ?? null };
+}
+
 export function createAuthedFetch(getSession: () => SessionState | null, setSession: SessionSetter) {
   return async function authedFetch(input: string, init: RequestInit = {}): Promise<Response> {
     const session = getSession();
@@ -294,6 +310,26 @@ export async function getProfile(authedFetch: AuthedFetch): Promise<Profile> {
   return body;
 }
 
+export async function updateProfile(
+  authedFetch: AuthedFetch,
+  payload: { masterPasswordHint: string }
+): Promise<Profile> {
+  const resp = await authedFetch('/api/accounts/profile', {
+    method: 'PUT',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({
+      masterPasswordHint: String(payload.masterPasswordHint || '').trim() || null,
+    }),
+  });
+  if (!resp.ok) {
+    const body = await parseJson<TokenError>(resp);
+    throw new Error(body?.error_description || body?.error || 'Save profile failed');
+  }
+  const body = await parseJson<Profile>(resp);
+  if (!body) throw new Error('Invalid profile');
+  return body;
+}
+
 export async function unlockVaultKey(profileKey: string, masterKey: Uint8Array): Promise<{ symEncKey: string; symMacKey: string }> {
   const encKey = await hkdfExpand(masterKey, 'enc', 32);
   const macKey = await hkdfExpand(masterKey, 'mac', 32);

webapp/src/lib/app-auth.ts

@@ -149,8 +149,7 @@ export function readInitialAppBootstrapState(): InitialAppBootstrapState {
   };
 }
 
-export async function bootstrapAppSession(): Promise<BootstrapAppResult> {
-  const initial = readInitialAppBootstrapState();
+export async function bootstrapAppSession(initial: InitialAppBootstrapState = readInitialAppBootstrapState()): Promise<BootstrapAppResult> {
   const defaultKdfIterations = initial.defaultKdfIterations;
   const jwtWarning = initial.jwtWarning;
 
@@ -309,6 +308,7 @@ export async function performRegistration(args: {
   email: string;
   name: string;
   password: string;
+  masterPasswordHint: string;
   inviteCode: string;
   fallbackIterations: number;
 }) {
@@ -316,6 +316,7 @@ export async function performRegistration(args: {
     email: args.email.trim().toLowerCase(),
     name: args.name.trim(),
     password: args.password,
+    masterPasswordHint: args.masterPasswordHint.trim(),
     inviteCode: args.inviteCode.trim(),
     fallbackIterations: args.fallbackIterations,
   });

webapp/src/lib/i18n.ts

@@ -458,6 +458,19 @@ const messages: Record<Locale, Record<string, string>> = {
     txt_password: "Password",
     txt_password_is_already_verified: "Password is already verified.",
     txt_passwords_do_not_match: "Passwords do not match",
+    txt_password_hint: "Password Hint",
+    txt_password_hint_optional: "Password Hint (optional)",
+    txt_password_hint_placeholder: "A clue only you would understand",
+    txt_password_hint_register_placeholder: "This hint can be shown directly on the web login page.",
+    txt_password_hint_register_help: "This hint can be shown directly on the web login page. Do not include your master password, recovery code, or anything that can reveal it outright.",
+    txt_password_hint_login_help: "Forgot the master password? Reveal the hint you saved during registration.",
+    txt_password_hint_login_note: "Only a hint is shown here. It should help you remember the password, not expose it.",
+    txt_show_password_hint: "Show Password Hint",
+    txt_hide_password_hint: "Hide Password Hint",
+    txt_loading_password_hint: "Loading hint...",
+    txt_password_hint_not_set: "No password hint is available for this email.",
+    txt_password_hint_load_failed: "Failed to load password hint",
+    txt_password_hint_too_long: "Password hint must be 120 characters or fewer",
     txt_phone: "Phone",
     txt_please_input_email_and_password: "Please input email and password",
     txt_please_input_master_password: "Please input master password",
@@ -1095,6 +1108,19 @@ const zhCNOverrides: Record<string, string> = {
   txt_opera_extension: 'Opera 扩展',
   txt_password_is_already_verified: '密码已验证',
   txt_passwords_do_not_match: '两次输入的密码不一致',
+  txt_password_hint: '密码提示',
+  txt_password_hint_optional: '密码提示（可选）',
+  txt_password_hint_placeholder: '写一句只有你自己看得懂的线索',
+  txt_password_hint_register_placeholder: '这个提示可以在网页登录页直接显示。',
+  txt_password_hint_register_help: '这个提示可以在网页登录页直接显示。不要填写主密码、恢复代码，或任何能直接暴露密码的信息。',
+  txt_password_hint_login_help: '忘记主密码时，可以查看注册时保存的提示。',
+  txt_password_hint_login_note: '这里只会显示提示语，不会显示你的主密码本身。',
+  txt_show_password_hint: '查看密码提示',
+  txt_hide_password_hint: '隐藏密码提示',
+  txt_loading_password_hint: '正在加载提示...',
+  txt_password_hint_not_set: '这个邮箱没有可显示的密码提示。',
+  txt_password_hint_load_failed: '加载密码提示失败',
+  txt_password_hint_too_long: '密码提示最多只能输入 120 个字符',
   txt_phone: '电话',
   txt_please_input_email_and_password: '请输入邮箱和密码',
   txt_please_input_master_password: '请输入主密码',

webapp/src/lib/types.ts

@@ -13,6 +13,7 @@ export interface Profile {
   email: string;
   name: string;
   key: string;
+  masterPasswordHint?: string | null;
   privateKey?: string | null;
   publicKey?: string | null;
   role: 'admin' | 'user';

webapp/src/styles.css

@@ -402,6 +402,41 @@ input[type='file'].input::file-selector-button:hover {
   color: #334155;
 }
 
+.field-help {
+  margin-top: 8px;
+  font-size: 13px;
+  line-height: 1.5;
+  color: #667085;
+}
+
+.auth-support-row {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 10px;
+  margin: -2px 0 12px;
+}
+
+.auth-link-btn {
+  border: none;
+  background: transparent;
+  padding: 0;
+  color: #1d4ed8;
+  font-size: 13px;
+  font-weight: 700;
+  cursor: pointer;
+}
+
+.auth-link-btn:hover {
+  text-decoration: underline;
+}
+
+.auth-link-btn:disabled {
+  color: #94a3b8;
+  cursor: not-allowed;
+  text-decoration: none;
+}
+
 .app-page {
   min-height: 100%;
   padding: 20px;
@@ -2417,6 +2452,11 @@ input[type='file'].input::file-selector-button:hover {
     font-size: 18px;
   }
 
+  .auth-support-row {
+    align-items: center;
+    flex-direction: row;
+  }
+
   .app-page {
     padding: 0;
     background: #f5f7fb;