crypto: implement webcrypto.randomUUID

Refs: https://wicg.github.io/uuid/
Refs: https://www.chromestatus.com/feature/5689159362543616

PR-URL: #39648
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>

Author: targos

doc/api/webcrypto.md

@@ -361,6 +361,16 @@ filled with random values, and a reference to `typedArray` is returned.
 
 An error will be thrown if the given `typedArray` is larger than 65,536 bytes.
 
+### `crypto.randomUUID()`
+<!-- YAML
+added: REPLACEME
+-->
+
+* Returns: {string}
+
+Generates a random [RFC 4122][] Version 4 UUID. The UUID is generated using a
+cryptographic pseudorandom number generator.
+
 ## Class: `CryptoKey`
 <!-- YAML
 added: v15.0.0
@@ -1771,4 +1781,5 @@ added: v15.0.0
 
 [JSON Web Key]: https://tools.ietf.org/html/rfc7517
 [Key usages]: #webcrypto_cryptokey_usages
+[RFC 4122]: https://www.rfc-editor.org/rfc/rfc4122.txt
 [Web Crypto API]: https://www.w3.org/TR/WebCryptoAPI/

lib/crypto.js

@@ -284,7 +284,7 @@ ObjectDefineProperties(module.exports, {
   webcrypto: {
     configurable: false,
     enumerable: true,
-    get() { return lazyRequire('internal/crypto/webcrypto'); }
+    get() { return lazyRequire('internal/crypto/webcrypto').crypto; }
   },
 
   // Aliases for randomBytes are deprecated.

lib/internal/crypto/webcrypto.js

@@ -64,8 +64,11 @@ const {
 
 const {
   getRandomValues,
+  randomUUID: _randomUUID,
 } = require('internal/crypto/random');
 
+const randomUUID = () => _randomUUID();
+
 async function generateKey(
   algorithm,
   extractable,
@@ -705,6 +708,12 @@ ObjectDefineProperties(
       writable: true,
       value: getRandomValues,
     },
+    randomUUID: {
+      enumerable: true,
+      configurable: true,
+      writable: true,
+      value: randomUUID,
+    },
     CryptoKey: {
       enumerable: true,
       configurable: true,
@@ -795,4 +804,8 @@ ObjectDefineProperties(
     }
   });
 
-module.exports = crypto;
+module.exports = {
+  Crypto,
+  SubtleCrypto,
+  crypto,
+};