fix: handle unavailable browser cryptography

Detect insecure or unsupported browser contexts before account registration and show localized HTTPS guidance instead of leaking a SubtleCrypto runtime error.

Fixes #320

package.json

@@ -15,6 +15,7 @@
     "domains:sync": "node scripts/sync-global-domains.mjs",
     "i18n": "node scripts/i18n-validate.cjs",
     "i18n:validate": "node scripts/i18n-validate.cjs",
+    "test:web-crypto": "tsx --test scripts/web-crypto-availability.test.ts",
     "test:webauthn-mobile": "node --test scripts/webauthn-mobile-connector.test.mjs",
     "test:webauthn-connector": "node --test scripts/webauthn-connector.test.mjs && tsx --test scripts/webauthn-connector-headers.test.ts",
     "test:webauthn-connectors": "node --test scripts/webauthn-mobile-connector.test.mjs scripts/webauthn-connector.test.mjs && tsx --test scripts/webauthn-connector-headers.test.ts",

scripts/web-crypto-availability.test.ts

@@ -0,0 +1,84 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+
+import { registerAccount } from '../webapp/src/lib/api/auth';
+import {
+  requireWebCrypto,
+  WebCryptoUnavailableError,
+} from '../webapp/src/lib/crypto';
+
+const supportedCrypto = {
+  subtle: {
+    importKey: () => Promise.reject(new Error('not used by capability checks')),
+  },
+  getRandomValues: <T>(array: T): T => array,
+} as unknown as Crypto;
+
+function restoreGlobalProperty(name: string, descriptor: PropertyDescriptor | undefined): void {
+  if (descriptor) {
+    Object.defineProperty(globalThis, name, descriptor);
+    return;
+  }
+  delete (globalThis as unknown as Record<string, unknown>)[name];
+}
+
+test('Web Crypto guard rejects insecure browser contexts', () => {
+  assert.throws(
+    () => requireWebCrypto({ crypto: supportedCrypto, isSecureContext: false }),
+    WebCryptoUnavailableError
+  );
+});
+
+test('Web Crypto guard rejects secure contexts without SubtleCrypto', () => {
+  const cryptoWithoutSubtle = {
+    getRandomValues: <T>(array: T): T => array,
+  } as unknown as Crypto;
+
+  assert.throws(
+    () => requireWebCrypto({ crypto: cryptoWithoutSubtle, isSecureContext: true }),
+    WebCryptoUnavailableError
+  );
+});
+
+test('Web Crypto guard accepts a secure supported browser', () => {
+  assert.equal(
+    requireWebCrypto({ crypto: supportedCrypto, isSecureContext: true }),
+    supportedCrypto
+  );
+});
+
+test('registration returns an actionable error without contacting the backend', async () => {
+  const cryptoDescriptor = Object.getOwnPropertyDescriptor(globalThis, 'crypto');
+  const secureContextDescriptor = Object.getOwnPropertyDescriptor(globalThis, 'isSecureContext');
+  const fetchDescriptor = Object.getOwnPropertyDescriptor(globalThis, 'fetch');
+  let fetchCalled = false;
+
+  Object.defineProperty(globalThis, 'crypto', { value: undefined, configurable: true });
+  Object.defineProperty(globalThis, 'isSecureContext', { value: false, configurable: true });
+  Object.defineProperty(globalThis, 'fetch', {
+    configurable: true,
+    value: async () => {
+      fetchCalled = true;
+      return new Response(null, { status: 500 });
+    },
+  });
+
+  try {
+    const result = await registerAccount({
+      email: 'first@example.test',
+      name: 'First Admin',
+      password: 'correct horse battery staple',
+      fallbackIterations: 600_000,
+    });
+
+    assert.deepEqual(result, {
+      ok: false,
+      message: 'Secure browser cryptography is unavailable. Open NodeWarden over HTTPS in a supported browser.',
+    });
+    assert.equal(fetchCalled, false);
+  } finally {
+    restoreGlobalProperty('crypto', cryptoDescriptor);
+    restoreGlobalProperty('isSecureContext', secureContextDescriptor);
+    restoreGlobalProperty('fetch', fetchDescriptor);
+  }
+});

webapp/src/lib/api/auth.ts

@@ -1,4 +1,12 @@
-import { bytesToBase64, decryptBw, encryptBw, hkdfExpand, pbkdf2 } from '../crypto';
+import {
+  bytesToBase64,
+  decryptBw,
+  encryptBw,
+  hkdfExpand,
+  pbkdf2,
+  requireWebCrypto,
+  WebCryptoUnavailableError,
+} from '../crypto';
 import { t, translateServerError } from '../i18n';
 import type { AuthorizedDevice } from '../types';
 import type {
@@ -428,14 +436,15 @@ export async function registerAccount(args: {
 }): Promise<{ ok: true } | { ok: false; message: string }> {
   try {
     const { email, name, password, masterPasswordHint, inviteCode, fallbackIterations } = args;
+    const webCrypto = requireWebCrypto();
     const masterKey = await pbkdf2(password, email, fallbackIterations, 32);
     const masterHash = await pbkdf2(masterKey, password, 1, 32);
     const encKey = await hkdfExpand(masterKey, 'enc', 32);
     const macKey = await hkdfExpand(masterKey, 'mac', 32);
-    const sym = crypto.getRandomValues(new Uint8Array(64));
+    const sym = webCrypto.getRandomValues(new Uint8Array(64));
     const encryptedVaultKey = await encryptBw(sym, encKey, macKey);
 
-    const keyPair = await crypto.subtle.generateKey(
+    const keyPair = await webCrypto.subtle.generateKey(
       {
         name: 'RSA-OAEP',
         modulusLength: 2048,
@@ -445,8 +454,8 @@ export async function registerAccount(args: {
       true,
       ['encrypt', 'decrypt']
     );
-    const publicKey = new Uint8Array(await crypto.subtle.exportKey('spki', keyPair.publicKey));
-    const privateKey = new Uint8Array(await crypto.subtle.exportKey('pkcs8', keyPair.privateKey));
+    const publicKey = new Uint8Array(await webCrypto.subtle.exportKey('spki', keyPair.publicKey));
+    const privateKey = new Uint8Array(await webCrypto.subtle.exportKey('pkcs8', keyPair.privateKey));
     const encryptedPrivateKey = await encryptBw(privateKey, sym.slice(0, 32), sym.slice(32, 64));
 
     const resp = await fetch('/api/accounts/register', {
@@ -474,6 +483,9 @@ export async function registerAccount(args: {
     }
     return { ok: true };
   } catch (error) {
+    if (error instanceof WebCryptoUnavailableError) {
+      return { ok: false, message: t('txt_web_crypto_unavailable') };
+    }
     return { ok: false, message: error instanceof Error ? translateServerError(error.message, error.message) : t('txt_register_failed') };
   }
 }

webapp/src/lib/crypto.ts

@@ -1,3 +1,34 @@
+export const WEB_CRYPTO_UNAVAILABLE_MESSAGE =
+  'Secure browser cryptography is unavailable. Open NodeWarden over HTTPS in a supported browser.';
+
+export class WebCryptoUnavailableError extends Error {
+  constructor() {
+    super(WEB_CRYPTO_UNAVAILABLE_MESSAGE);
+    this.name = 'WebCryptoUnavailableError';
+  }
+}
+
+interface WebCryptoEnvironment {
+  crypto?: Crypto;
+  isSecureContext?: boolean;
+}
+
+export function requireWebCrypto(
+  environment: WebCryptoEnvironment = globalThis as unknown as WebCryptoEnvironment
+): Crypto {
+  const cryptoApi = environment.crypto;
+  if (
+    environment.isSecureContext === false ||
+    !cryptoApi ||
+    typeof cryptoApi.getRandomValues !== 'function' ||
+    !cryptoApi.subtle ||
+    typeof cryptoApi.subtle.importKey !== 'function'
+  ) {
+    throw new WebCryptoUnavailableError();
+  }
+  return cryptoApi;
+}
+
 export function bytesToBase64(bytes: Uint8Array): string {
   let s = '';
   for (let i = 0; i < bytes.length; i += 1) s += String.fromCharCode(bytes[i]);
@@ -24,7 +55,7 @@ export function toBufferSource(bytes: Uint8Array): ArrayBuffer {
 
 export async function sha256Base64(value: string): Promise<string> {
   const bytes = new TextEncoder().encode(value);
-  const hash = await crypto.subtle.digest('SHA-256', toBufferSource(bytes));
+  const hash = await requireWebCrypto().subtle.digest('SHA-256', toBufferSource(bytes));
   return bytesToBase64(new Uint8Array(hash));
 }
 
@@ -51,7 +82,7 @@ function getHmacSha256Key(keyBytes: Uint8Array): Promise<CryptoKey> {
   return getCachedCryptoKey(
     hmacSha256KeyCache,
     keyBytes,
-    () => crypto.subtle.importKey('raw', toBufferSource(keyBytes), { name: 'HMAC', hash: 'SHA-256' }, false, ['sign'])
+    () => requireWebCrypto().subtle.importKey('raw', toBufferSource(keyBytes), { name: 'HMAC', hash: 'SHA-256' }, false, ['sign'])
   );
 }
 
@@ -59,7 +90,7 @@ function getAesCbcEncryptKey(keyBytes: Uint8Array): Promise<CryptoKey> {
   return getCachedCryptoKey(
     aesCbcEncryptKeyCache,
     keyBytes,
-    () => crypto.subtle.importKey('raw', toBufferSource(keyBytes), { name: 'AES-CBC' }, false, ['encrypt'])
+    () => requireWebCrypto().subtle.importKey('raw', toBufferSource(keyBytes), { name: 'AES-CBC' }, false, ['encrypt'])
   );
 }
 
@@ -67,7 +98,7 @@ function getAesCbcDecryptKey(keyBytes: Uint8Array): Promise<CryptoKey> {
   return getCachedCryptoKey(
     aesCbcDecryptKeyCache,
     keyBytes,
-    () => crypto.subtle.importKey('raw', toBufferSource(keyBytes), { name: 'AES-CBC' }, false, ['decrypt'])
+    () => requireWebCrypto().subtle.importKey('raw', toBufferSource(keyBytes), { name: 'AES-CBC' }, false, ['decrypt'])
   );
 }
 
@@ -88,8 +119,9 @@ export async function pbkdf2(
 ): Promise<Uint8Array> {
   const pwdBytes = typeof passwordOrBytes === 'string' ? new TextEncoder().encode(passwordOrBytes) : passwordOrBytes;
   const saltBytes = typeof saltOrBytes === 'string' ? new TextEncoder().encode(saltOrBytes) : saltOrBytes;
-  const key = await crypto.subtle.importKey('raw', toBufferSource(pwdBytes), 'PBKDF2', false, ['deriveBits']);
-  const bits = await crypto.subtle.deriveBits(
+  const subtle = requireWebCrypto().subtle;
+  const key = await subtle.importKey('raw', toBufferSource(pwdBytes), 'PBKDF2', false, ['deriveBits']);
+  const bits = await subtle.deriveBits(
     { name: 'PBKDF2', hash: 'SHA-256', salt: toBufferSource(saltBytes), iterations },
     key,
     keyLen * 8
@@ -99,7 +131,8 @@ export async function pbkdf2(
 
 export async function hkdfExpand(prk: Uint8Array, info: string, length: number): Promise<Uint8Array> {
   const infoBytes = new TextEncoder().encode(info || '');
-  const key = await crypto.subtle.importKey('raw', toBufferSource(prk), { name: 'HMAC', hash: 'SHA-256' }, false, ['sign']);
+  const subtle = requireWebCrypto().subtle;
+  const key = await subtle.importKey('raw', toBufferSource(prk), { name: 'HMAC', hash: 'SHA-256' }, false, ['sign']);
   const result = new Uint8Array(length);
   let previous = new Uint8Array(0);
   let offset = 0;
@@ -110,7 +143,7 @@ export async function hkdfExpand(prk: Uint8Array, info: string, length: number):
     input.set(previous, 0);
     input.set(infoBytes, previous.length);
     input[input.length - 1] = counter & 0xff;
-    previous = new Uint8Array(await crypto.subtle.sign('HMAC', key, toBufferSource(input)));
+    previous = new Uint8Array(await subtle.sign('HMAC', key, toBufferSource(input)));
     const copyLen = Math.min(previous.length, length - offset);
     result.set(previous.slice(0, copyLen), offset);
     offset += copyLen;
@@ -134,28 +167,29 @@ export async function hkdf(
     info: toBufferSource(infoBytes),
     hash: 'SHA-256',
   };
-  const key = await crypto.subtle.importKey('raw', toBufferSource(ikm), 'HKDF', false, ['deriveBits']);
-  const bits = await crypto.subtle.deriveBits(params, key, outputByteSize * 8);
+  const subtle = requireWebCrypto().subtle;
+  const key = await subtle.importKey('raw', toBufferSource(ikm), 'HKDF', false, ['deriveBits']);
+  const bits = await subtle.deriveBits(params, key, outputByteSize * 8);
   return new Uint8Array(bits);
 }
 
 async function hmacSha256(keyBytes: Uint8Array, dataBytes: Uint8Array): Promise<Uint8Array> {
   const key = await getHmacSha256Key(keyBytes);
-  return new Uint8Array(await crypto.subtle.sign('HMAC', key, toBufferSource(dataBytes)));
+  return new Uint8Array(await requireWebCrypto().subtle.sign('HMAC', key, toBufferSource(dataBytes)));
 }
 
 async function encryptAesCbc(data: Uint8Array, key: Uint8Array, iv: Uint8Array): Promise<Uint8Array> {
   const cryptoKey = await getAesCbcEncryptKey(key);
-  return new Uint8Array(await crypto.subtle.encrypt({ name: 'AES-CBC', iv: toBufferSource(iv) }, cryptoKey, toBufferSource(data)));
+  return new Uint8Array(await requireWebCrypto().subtle.encrypt({ name: 'AES-CBC', iv: toBufferSource(iv) }, cryptoKey, toBufferSource(data)));
 }
 
 async function decryptAesCbc(data: Uint8Array, key: Uint8Array, iv: Uint8Array): Promise<Uint8Array> {
   const cryptoKey = await getAesCbcDecryptKey(key);
-  return new Uint8Array(await crypto.subtle.decrypt({ name: 'AES-CBC', iv: toBufferSource(iv) }, cryptoKey, toBufferSource(data)));
+  return new Uint8Array(await requireWebCrypto().subtle.decrypt({ name: 'AES-CBC', iv: toBufferSource(iv) }, cryptoKey, toBufferSource(data)));
 }
 
 export async function encryptBwFileData(data: Uint8Array, encKey: Uint8Array, macKey: Uint8Array): Promise<Uint8Array> {
-  const iv = crypto.getRandomValues(new Uint8Array(16));
+  const iv = requireWebCrypto().getRandomValues(new Uint8Array(16));
   const cipher = await encryptAesCbc(data, encKey, iv);
   const mac = await hmacSha256(macKey, concatBytes(iv, cipher));
   const out = new Uint8Array(1 + iv.length + mac.length + cipher.length);
@@ -179,7 +213,7 @@ export async function decryptBwFileData(encrypted: Uint8Array, encKey: Uint8Arra
 }
 
 export async function encryptBw(data: Uint8Array, encKey: Uint8Array, macKey: Uint8Array): Promise<string> {
-  const iv = crypto.getRandomValues(new Uint8Array(16));
+  const iv = requireWebCrypto().getRandomValues(new Uint8Array(16));
   const cipher = await encryptAesCbc(data, encKey, iv);
   const mac = await hmacSha256(macKey, concatBytes(iv, cipher));
   return `2.${bytesToBase64(iv)}|${bytesToBase64(cipher)}|${bytesToBase64(mac)}`;
@@ -556,8 +590,9 @@ export async function calcTotpNow(rawSecret: string, nowMs: number = Date.now())
     message[i] = c & 0xff;
     c = Math.floor(c / 256);
   }
-  const key = await crypto.subtle.importKey('raw', toBufferSource(keyBytes), { name: 'HMAC', hash: algorithm }, false, ['sign']);
-  const hs = new Uint8Array(await crypto.subtle.sign('HMAC', key, toBufferSource(message)));
+  const subtle = requireWebCrypto().subtle;
+  const key = await subtle.importKey('raw', toBufferSource(keyBytes), { name: 'HMAC', hash: algorithm }, false, ['sign']);
+  const hs = new Uint8Array(await subtle.sign('HMAC', key, toBufferSource(message)));
   const offset = hs[hs.length - 1] & 0x0f;
   const bin = ((hs[offset] & 0x7f) << 24) | ((hs[offset + 1] & 0xff) << 16) | ((hs[offset + 2] & 0xff) << 8) | (hs[offset + 3] & 0xff);
   let code = (bin % (10 ** digits)).toString().padStart(digits, '0');

webapp/src/lib/i18n.ts

@@ -238,6 +238,7 @@ export function translateServerError(message: string | null | undefined, fallbac
     'WebDAV server URL is required': 'txt_backup_error_webdav_url_required',
     'WebDAV server URL must start with http:// or https://': 'txt_backup_error_webdav_url_protocol',
     'WebDAV username is required': 'txt_backup_error_webdav_username_required',
+    'Secure browser cryptography is unavailable. Open NodeWarden over HTTPS in a supported browser.': 'txt_web_crypto_unavailable',
     'masterPasswordHash is required': 'txt_server_error_master_password_hash_required',
     'masterPasswordHash or userVerificationToken is required': 'txt_server_error_master_password_or_verification_required',
   }[normalized];

webapp/src/lib/i18n/locales/de.ts

@@ -511,6 +511,7 @@ const de: Record<string, string> = {
   "txt_create_account": "Konto erstellen",
   "txt_registering": "Konto wird erstellt...",
   "txt_register_failed": "Registrierung fehlgeschlagen",
+  "txt_web_crypto_unavailable": "Sichere Browser-Kryptografie ist nicht verfügbar. Öffnen Sie NodeWarden über HTTPS in einem unterstützten Browser.",
   "txt_create_folder": "Ordner erstellen",
   "txt_create_folder_failed": "Fehler beim Erstellen des Ordners",
   "txt_create_item_failed": "Fehler beim Erstellen des Eintrags",

webapp/src/lib/i18n/locales/en.ts

@@ -534,6 +534,7 @@ const en: Record<string, string> = {
   "txt_create_account": "Create Account",
   "txt_registering": "Creating account...",
   "txt_register_failed": "Register failed",
+  "txt_web_crypto_unavailable": "Secure browser cryptography is unavailable. Open NodeWarden over HTTPS in a supported browser.",
   "txt_create_folder": "Create Folder",
   "txt_create_folder_failed": "Create folder failed",
   "txt_create_item_failed": "Create item failed",

webapp/src/lib/i18n/locales/es.ts

@@ -511,6 +511,7 @@ const es: Record<string, string> = {
   "txt_create_account": "Crear cuenta",
   "txt_registering": "Creando cuenta...",
   "txt_register_failed": "Error al registrarse",
+  "txt_web_crypto_unavailable": "La criptografía segura del navegador no está disponible. Abra NodeWarden mediante HTTPS en un navegador compatible.",
   "txt_create_folder": "Crear carpeta",
   "txt_create_folder_failed": "Error al crear carpeta",
   "txt_create_item_failed": "Error al crear elemento",

webapp/src/lib/i18n/locales/fi.ts

@@ -511,6 +511,7 @@ const fi: Record<string, string> = {
   "txt_create_account": "Luo tili",
   "txt_registering": "Luodaan tiliä...",
   "txt_register_failed": "Rekisteröinti epäonnistui",
+  "txt_web_crypto_unavailable": "Selaimen suojattu salaus ei ole käytettävissä. Avaa NodeWarden HTTPS-yhteydellä tuetussa selaimessa.",
   "txt_create_folder": "Luo kansio",
   "txt_create_folder_failed": "Kansion luonti epäonnistui",
   "txt_create_item_failed": "Nimikkeen luonti epäonnistui",

webapp/src/lib/i18n/locales/fr.ts

@@ -511,6 +511,7 @@ const fr: Record<string, string> = {
   "txt_create_account": "Créer un compte",
   "txt_registering": "Création du compte...",
   "txt_register_failed": "L'inscription a échoué",
+  "txt_web_crypto_unavailable": "La cryptographie sécurisée du navigateur n’est pas disponible. Ouvrez NodeWarden via HTTPS dans un navigateur compatible.",
   "txt_create_folder": "Créer un dossier",
   "txt_create_folder_failed": "La création du dossier a échoué",
   "txt_create_item_failed": "La création de l'élément a échoué",

webapp/src/lib/i18n/locales/it.ts

@@ -511,6 +511,7 @@ const it: Record<string, string> = {
   "txt_create_account": "Crea Account",
   "txt_registering": "Creazione Account in corso...",
   "txt_register_failed": "Registrazione fallita",
+  "txt_web_crypto_unavailable": "La crittografia sicura del browser non è disponibile. Apri NodeWarden tramite HTTPS in un browser supportato.",
   "txt_create_folder": "Crea cartella",
   "txt_create_folder_failed": "Impossibile creare la cartella",
   "txt_create_item_failed": "Impossibile creare l'elemento",

webapp/src/lib/i18n/locales/ru.ts

@@ -511,6 +511,7 @@ const ru: Record<string, string> = {
   "txt_create_account": "Создать учетную запись",
   "txt_registering": "Создание учетной записи...",
   "txt_register_failed": "Не удалось зарегистрироваться",
+  "txt_web_crypto_unavailable": "Безопасная криптография браузера недоступна. Откройте NodeWarden по HTTPS в поддерживаемом браузере.",
   "txt_create_folder": "Создать папку",
   "txt_create_folder_failed": "Создать папку не удалось",
   "txt_create_item_failed": "Создать элемент не удалось",

webapp/src/lib/i18n/locales/sv.ts

@@ -511,6 +511,7 @@ const sv: Record<string, string> = {
   "txt_create_account": "Skapa konto",
   "txt_registering": "Skapar konto...",
   "txt_register_failed": "Registrering misslyckades",
+  "txt_web_crypto_unavailable": "Säker webbläsarkryptografi är inte tillgänglig. Öppna NodeWarden via HTTPS i en webbläsare som stöds.",
   "txt_create_folder": "Skapa mapp",
   "txt_create_folder_failed": "Misslyckades med att skapa mapp",
   "txt_create_item_failed": "Misslyckades med att skapa objekt",

webapp/src/lib/i18n/locales/zh-CN.ts

@@ -514,6 +514,7 @@ const zhCN: Record<string, string> = {
   "txt_create_account": "创建账户",
   "txt_registering": "正在注册...",
   "txt_register_failed": "注册失败",
+  "txt_web_crypto_unavailable": "当前浏览器环境无法使用安全加密。请通过 HTTPS 打开 NodeWarden，并使用受支持的现代浏览器。",
   "txt_create_folder": "创建文件夹",
   "txt_create_folder_failed": "创建文件夹失败",
   "txt_create_item_failed": "创建项目失败",

webapp/src/lib/i18n/locales/zh-TW.ts

@@ -514,6 +514,7 @@ const zhTW: Record<string, string> = {
   "txt_create_account": "創建賬戶",
   "txt_registering": "正在註冊...",
   "txt_register_failed": "註冊失敗",
+  "txt_web_crypto_unavailable": "目前瀏覽器環境無法使用安全加密。請透過 HTTPS 開啟 NodeWarden，並使用受支援的現代瀏覽器。",
   "txt_create_folder": "創建文件夾",
   "txt_create_folder_failed": "創建文件夾失敗",
   "txt_create_item_failed": "創建項目失敗",