fix(security): harden auth and request limits

src/config/limits.ts

@@ -62,6 +62,9 @@
     // Refresh-token grant budget per IP per minute.
     // refresh_token 授权每 IP 每分钟请求配额。
     refreshTokenRequestsPerMinute: 30,
+    // Passwordless/auth-request creation budget per IP/email/device per minute.
+    // 免密/设备审批请求创建接口每 IP/邮箱/设备每分钟配额。
+    authRequestRequestsPerMinute: 5,
     // Fixed window size for API rate limiting in seconds.
     // API 限流固定窗口大小（秒）。
     apiWindowSeconds: 60,

src/handlers/accounts.ts

@@ -42,6 +42,9 @@ function looksLikeEncString(value: string): boolean {
  */
 function validateKdfParams(kdfType: number | undefined, kdfIterations: number | undefined, kdfMemory?: number | undefined, kdfParallelism?: number | undefined): string | null {
   const type = kdfType ?? 0;
+  if (type !== 0 && type !== 1) {
+    return 'KDF type must be PBKDF2-SHA256 or Argon2id';
+  }
   if (type === 0) {
     // PBKDF2-SHA256: minimum 100 000 iterations
     if (typeof kdfIterations === 'number' && kdfIterations < 100_000) {
@@ -448,7 +451,7 @@ export async function handleGetPasswordHint(request: Request, env: Env): Promise
   }
 
   const rateLimit = new RateLimitService(env.DB);
-  const minuteBudget = await rateLimit.consumeBudgetWithWindow(
+  const minuteBudget = await rateLimit.consumeStrictBudgetWithWindow(
     `${clientIdentifier}:password-hint`,
     LIMITS.rateLimit.passwordHintRequestsPerMinute,
     60
@@ -470,7 +473,7 @@ export async function handleGetPasswordHint(request: Request, env: Env): Promise
     );
   }
 
-  const hourlyBudget = await rateLimit.consumeBudgetWithWindow(
+  const hourlyBudget = await rateLimit.consumeStrictBudgetWithWindow(
     `${clientIdentifier}:password-hint-hour`,
     LIMITS.rateLimit.passwordHintRequestsPerHour,
     60 * 60
@@ -734,6 +737,11 @@ export async function handleChangePassword(request: Request, env: Env, userId: s
   const nextKdfParallelism = body.kdfParallelism ?? readNestedNumber(body, ['unlockData', 'kdf', 'parallelism']);
   const kdfErr = validateKdfParams(nextKdf, nextKdfIterations, nextKdfMemory, nextKdfParallelism);
   if (kdfErr) return errorResponse(kdfErr, 400);
+  const shouldUpdateHint = typeof body.masterPasswordHint === 'string' || body.masterPasswordHint === null;
+  const nextMasterPasswordHint = shouldUpdateHint ? normalizeMasterPasswordHint(body.masterPasswordHint) : undefined;
+  if (nextMasterPasswordHint && nextMasterPasswordHint.length > 120) {
+    return errorResponse('masterPasswordHint must be 120 characters or fewer', 400);
+  }
 
   user.masterPasswordHash = await auth.hashPasswordServer(newMasterPasswordHash, user.email);
   if (nextKey) user.key = nextKey;
@@ -743,8 +751,8 @@ export async function handleChangePassword(request: Request, env: Env, userId: s
   if (typeof nextKdfIterations === 'number') user.kdfIterations = nextKdfIterations;
   if (typeof nextKdfMemory === 'number') user.kdfMemory = nextKdfMemory;
   if (typeof nextKdfParallelism === 'number') user.kdfParallelism = nextKdfParallelism;
-  if (typeof body.masterPasswordHint === 'string' || body.masterPasswordHint === null) {
-    user.masterPasswordHint = body.masterPasswordHint;
+  if (shouldUpdateHint) {
+    user.masterPasswordHint = nextMasterPasswordHint ?? null;
   }
   user.securityStamp = generateUUID();
   user.updatedAt = new Date().toISOString();

src/handlers/attachments.ts

@@ -124,6 +124,10 @@ async function processAttachmentUpload(
   }
 
   const path = getAttachmentObjectKey(cipherId, attachment.id);
+  if (await getBlobObject(env, path)) {
+    return errorResponse('Attachment file has already been uploaded', 409);
+  }
+
   try {
     await putBlobObject(env, path, upload.body, {
       size: upload.size,

src/handlers/auth-requests.ts

@@ -5,6 +5,8 @@ import { readAuthRequestDeviceInfo, readActingDeviceIdentifier } from '../utils/
 import { errorResponse, jsonResponse } from '../utils/response';
 import { isAuthRequestExpired } from '../services/storage-auth-request-repo';
 import { notifyAuthRequestResponse, notifyUserAuthRequest } from '../durable/notifications-hub';
+import { RateLimitService, getClientIdentifier } from '../services/ratelimit';
+import { LIMITS } from '../config/limits';
 
 const AUTH_REQUEST_TYPE_AUTHENTICATE_AND_UNLOCK = 0;
 const AUTH_REQUEST_TYPE_UNLOCK = 1;
@@ -131,6 +133,30 @@ async function readJsonBody(request: Request): Promise<Record<string, any> | nul
   }
 }
 
+async function enforceAuthRequestCreateRateLimit(
+  request: Request,
+  env: Env,
+  email: string,
+  deviceIdentifier: string
+): Promise<Response | null> {
+  const clientIdentifier = getClientIdentifier(request);
+  if (!clientIdentifier) return errorResponse('Client IP is required', 403);
+
+  const rateLimit = new RateLimitService(env.DB);
+  const limit = LIMITS.rateLimit.authRequestRequestsPerMinute;
+  const encodedEmail = encodeURIComponent(email || 'missing');
+  const encodedDevice = encodeURIComponent(deviceIdentifier || 'missing');
+  const budgets = await Promise.all([
+    rateLimit.consumeStrictBudget(`auth-request:ip:${clientIdentifier}`, limit),
+    rateLimit.consumeStrictBudget(`auth-request:email:${encodedEmail}`, limit),
+    rateLimit.consumeStrictBudget(`auth-request:device:${encodedDevice}`, limit),
+  ]);
+  const blocked = budgets.find((budget) => !budget.allowed);
+  if (!blocked) return null;
+
+  return errorResponse('Too many authentication requests. Try again later.', 429);
+}
+
 function readBodyValue(body: Record<string, any>, names: string[]): unknown {
   for (const name of names) {
     if (body[name] !== undefined) return body[name];
@@ -164,6 +190,8 @@ export async function handleCreateAuthRequest(request: Request, env: Env): Promi
   if (!email || !publicKey || !accessCode || !deviceInfo.deviceIdentifier) {
     return errorResponse('Email, public key, device identifier, and access code are required.', 400);
   }
+  const rateLimitResponse = await enforceAuthRequestCreateRateLimit(request, env, email, deviceInfo.deviceIdentifier);
+  if (rateLimitResponse) return rateLimitResponse;
   if (!isSupportedAuthRequestType(type) || type === AUTH_REQUEST_TYPE_ADMIN_APPROVAL) {
     return errorResponse('Invalid auth request type.', 400);
   }

src/router-admin.ts

@@ -13,6 +13,23 @@ import {
   handleAdminClearAuditLogs,
 } from './handlers/admin';
 import { handleAdminBackupRoute } from './router-admin-backup';
+import { errorResponse } from './utils/response';
+
+function isKnownAdminPath(path: string): boolean {
+  return (
+    path === '/api/admin/users' ||
+    path === '/api/admin/logs' ||
+    path === '/api/admin/logs/settings' ||
+    path === '/api/admin/invites' ||
+    path.startsWith('/api/admin/backup') ||
+    /^\/api\/admin\/invites\/[^/]+$/i.test(path) ||
+    /^\/api\/admin\/users\/[a-f0-9-]+(?:\/status)?$/i.test(path)
+  );
+}
+
+function isActiveAdmin(user: User): boolean {
+  return user.role === 'admin' && user.status === 'active';
+}
 
 export async function handleAdminRoute(
   request: Request,
@@ -21,6 +38,13 @@ export async function handleAdminRoute(
   path: string,
   method: string
 ): Promise<Response | null> {
+  if (!isKnownAdminPath(path)) {
+    return null;
+  }
+  if (!isActiveAdmin(actorUser)) {
+    return errorResponse('Forbidden', 403);
+  }
+
   if (path === '/api/admin/users' && method === 'GET') {
     return handleAdminListUsers(request, env, actorUser);
   }

src/router-public.ts

@@ -465,6 +465,8 @@ export async function handlePublicRoute(
   }
 
   if ((path === '/identity/accounts/recover-2fa' || path === '/api/accounts/recover-2fa') && method === 'POST') {
+    const blocked = await enforcePublicRateLimit('public-sensitive', LIMITS.rateLimit.sensitivePublicRequestsPerMinute);
+    if (blocked) return blocked;
     return handleRecoverTwoFactor(request, env);
   }
 

src/router.ts

@@ -36,6 +36,70 @@ function isImportBypassRequest(request: Request, path: string, method: string):
   return false;
 }
 
+const BODY_LIMIT_METHODS = new Set(['POST', 'PUT', 'PATCH', 'DELETE']);
+
+function isLargeUploadPath(path: string): boolean {
+  return (
+    /^\/api\/ciphers\/[a-f0-9-]+\/attachment\/[a-f0-9-]+$/i.test(path) ||
+    /^\/api\/sends\/[a-f0-9-]+\/file\/[a-f0-9-]+$/i.test(path) ||
+    path === '/api/admin/backup/import'
+  );
+}
+
+async function enforceRequestBodyLimit(
+  request: Request,
+  path: string,
+  method: string
+): Promise<Request | Response> {
+  if (!BODY_LIMIT_METHODS.has(method) || isLargeUploadPath(path) || !request.body) {
+    return request;
+  }
+
+  const contentLengthRaw = request.headers.get('Content-Length');
+  if (contentLengthRaw) {
+    const contentLength = Number(contentLengthRaw);
+    if (Number.isFinite(contentLength) && contentLength > LIMITS.request.maxBodyBytes) {
+      return errorResponse('Request body too large', 413);
+    }
+    if (Number.isFinite(contentLength) && contentLength >= 0) {
+      return request;
+    }
+  }
+
+  const reader = request.body.getReader();
+  const chunks: Uint8Array[] = [];
+  let total = 0;
+  while (true) {
+    const { done, value } = await reader.read();
+    if (done) break;
+    if (!value) continue;
+    total += value.byteLength;
+    if (total > LIMITS.request.maxBodyBytes) {
+      try {
+        await reader.cancel();
+      } catch {
+        // Ignore cancellation races after the oversized body is rejected.
+      }
+      return errorResponse('Request body too large', 413);
+    }
+    chunks.push(value);
+  }
+
+  const body = new Uint8Array(total);
+  let offset = 0;
+  for (const chunk of chunks) {
+    body.set(chunk, offset);
+    offset += chunk.byteLength;
+  }
+
+  return new Request(request.url, {
+    method: request.method,
+    headers: request.headers,
+    body,
+    redirect: request.redirect,
+  });
+}
+
 export async function handleRequest(request: Request, env: Env): Promise<Response> {
   const url = new URL(request.url);
   const path = url.pathname;
@@ -60,7 +124,10 @@ export async function handleRequest(request: Request, env: Env): Promise<Respons
     }
 
     const rateLimit = new RateLimitService(env.DB);
-    const check = await rateLimit.consumeBudget(`${clientId}:${category}`, maxRequests);
+    const shouldUseStrictBudget = category === 'public-sensitive' || category === 'register';
+    const check = shouldUseStrictBudget
+      ? await rateLimit.consumeStrictBudget(`${clientId}:${category}`, maxRequests)
+      : await rateLimit.consumeBudget(`${clientId}:${category}`, maxRequests);
     if (check.allowed) return null;
 
     return new Response(
@@ -84,16 +151,11 @@ export async function handleRequest(request: Request, env: Env): Promise<Respons
   }
 
   try {
-    const isLargeUploadPath =
-      /^\/api\/ciphers\/[a-f0-9-]+\/attachment\/[a-f0-9-]+$/i.test(path) ||
-      /^\/api\/sends\/[a-f0-9-]+\/file\/[a-f0-9-]+$/i.test(path) ||
-      path === '/api/admin/backup/import';
-    if (!isLargeUploadPath) {
-      const contentLength = parseInt(request.headers.get('Content-Length') || '0', 10);
-      if (contentLength > LIMITS.request.maxBodyBytes) {
-        return errorResponse('Request body too large', 413);
-      }
+    const bodyLimitResult = await enforceRequestBodyLimit(request, path, method);
+    if (bodyLimitResult instanceof Response) {
+      return bodyLimitResult;
     }
+    request = bodyLimitResult;
 
     const secretIssue = jwtSecretUnsafeReason(env);
     if (secretIssue && !canServeWithUnsafeJwtSecret(path, method)) {

src/services/ratelimit.ts

@@ -3,6 +3,7 @@ import { LIMITS } from '../config/limits';
 // Rate limiting service.
 // - Login attempts: D1-backed (low volume, security-critical, needs cross-colo persistence).
 // - API budgets: Cloudflare Cache API (high volume, auto-expires, zero D1 writes).
+// - Strict budgets: D1-backed fixed windows for low-volume anonymous sensitive endpoints.
 
 const CONFIG = {
   LOGIN_MAX_ATTEMPTS: LIMITS.rateLimit.loginMaxAttempts,
@@ -12,11 +13,14 @@ const CONFIG = {
 
 export class RateLimitService {
   private static loginIpTableReady = false;
+  private static strictBudgetTableReady = false;
   private static lastLoginIpCleanupAt = 0;
+  private static lastStrictBudgetCleanupAt = 0;
 
   private static readonly PERIODIC_CLEANUP_PROBABILITY = LIMITS.rateLimit.cleanupProbability;
   private static readonly LOGIN_IP_CLEANUP_INTERVAL_MS = LIMITS.rateLimit.loginIpCleanupIntervalMs;
   private static readonly LOGIN_IP_RETENTION_MS = LIMITS.rateLimit.loginIpRetentionMs;
+  private static readonly STRICT_BUDGET_CLEANUP_INTERVAL_MS = LIMITS.rateLimit.loginIpCleanupIntervalMs;
 
   constructor(private db: D1Database) {}
 
@@ -58,6 +62,35 @@ export class RateLimitService {
     RateLimitService.loginIpTableReady = true;
   }
 
+  private async ensureStrictBudgetTable(): Promise<void> {
+    if (RateLimitService.strictBudgetTableReady) return;
+
+    await this.db
+      .prepare(
+        'CREATE TABLE IF NOT EXISTS rate_limit_buckets (' +
+        'bucket_key TEXT PRIMARY KEY, ' +
+        'count INTEGER NOT NULL, ' +
+        'expires_at INTEGER NOT NULL, ' +
+        'updated_at INTEGER NOT NULL' +
+        ')'
+      )
+      .run();
+
+    await this.db
+      .prepare('CREATE INDEX IF NOT EXISTS idx_rate_limit_buckets_expires ON rate_limit_buckets(expires_at)')
+      .run();
+    RateLimitService.strictBudgetTableReady = true;
+  }
+
+  private async maybeCleanupStrictBudgets(nowMs: number): Promise<void> {
+    if (!this.shouldRunCleanup(RateLimitService.lastStrictBudgetCleanupAt, RateLimitService.STRICT_BUDGET_CLEANUP_INTERVAL_MS)) {
+      return;
+    }
+
+    await this.db.prepare('DELETE FROM rate_limit_buckets WHERE expires_at < ?').bind(nowMs).run();
+    RateLimitService.lastStrictBudgetCleanupAt = nowMs;
+  }
+
   async checkLoginAttempt(ip: string): Promise<{
     allowed: boolean;
     remainingAttempts: number;
@@ -174,6 +207,59 @@ export class RateLimitService {
     return { allowed: true, remaining: Math.max(0, maxRequests - count) };
   }
 
+  async consumeStrictBudget(
+    identifier: string,
+    maxRequests: number
+  ): Promise<{ allowed: boolean; remaining: number; retryAfterSeconds?: number }> {
+    return this.consumeStrictBudgetWithWindow(identifier, maxRequests, CONFIG.API_WINDOW_SECONDS);
+  }
+
+  async consumeStrictBudgetWithWindow(
+    identifier: string,
+    maxRequests: number,
+    windowSeconds: number
+  ): Promise<{ allowed: boolean; remaining: number; retryAfterSeconds?: number }> {
+    await this.ensureStrictBudgetTable();
+
+    const key = String(identifier || '').trim() || 'unknown';
+    const max = Math.max(1, Math.floor(maxRequests));
+    const windowSize = Math.max(1, Math.floor(windowSeconds));
+    const nowMs = Date.now();
+    const nowSec = Math.floor(nowMs / 1000);
+    const windowStart = nowSec - (nowSec % windowSize);
+    const windowEndMs = (windowStart + windowSize) * 1000;
+    const retryAfterSeconds = Math.max(1, Math.ceil((windowEndMs - nowMs) / 1000));
+    const bucketKey = `${key}:${windowStart}`;
+
+    await this.maybeCleanupStrictBudgets(nowMs);
+    await this.db
+      .prepare(
+        'INSERT OR IGNORE INTO rate_limit_buckets(bucket_key, count, expires_at, updated_at) VALUES(?, 0, ?, ?)'
+      )
+      .bind(bucketKey, windowEndMs, nowMs)
+      .run();
+
+    const update = await this.db
+      .prepare(
+        'UPDATE rate_limit_buckets SET count = count + 1, expires_at = ?, updated_at = ? ' +
+        'WHERE bucket_key = ? AND count < ?'
+      )
+      .bind(windowEndMs, nowMs, bucketKey, max)
+      .run();
+
+    const allowed = Number(update.meta?.changes ?? 0) > 0;
+    const row = await this.db
+      .prepare('SELECT count FROM rate_limit_buckets WHERE bucket_key = ?')
+      .bind(bucketKey)
+      .first<{ count: number }>();
+    const count = Math.max(0, Number(row?.count || 0));
+
+    if (!allowed) {
+      return { allowed: false, remaining: 0, retryAfterSeconds };
+    }
+    return { allowed: true, remaining: Math.max(0, max - count) };
+  }
+
   // General-purpose fixed-window budget.
   // Callers supply an identifier (must be unique per rate-limit category) and the
   // per-window maximum.  This single method replaces all previous specialised

src/services/storage-account-passkey-repo.ts

@@ -268,7 +268,7 @@ export async function updateAccountPasskeyEncryption(
   const result = await db
     .prepare(
       'UPDATE webauthn_credentials SET encrypted_user_key = ?, encrypted_public_key = ?, encrypted_private_key = ?, supports_prf = 1, updated_at = ? ' +
-        'WHERE user_id = ? AND credential_id = ?'
+        "WHERE user_id = ? AND credential_id = ? AND purpose = 'login'"
     )
     .bind(encryptedUserKey, encryptedPublicKey, encryptedPrivateKey, updatedAt, userId, credentialId)
     .run();