crypto: add null check to outputLength logic

The Hash constructor's outputLength logic checks if the options
input is an object, but doesn't check for null objects. This
commit adds that check.

PR-URL: #28864
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>

lib/internal/crypto/hash.js

@@ -36,7 +36,8 @@ function Hash(algorithm, options) {
   if (!(this instanceof Hash))
     return new Hash(algorithm, options);
   validateString(algorithm, 'algorithm');
-  const xofLen = typeof options === 'object' ? options.outputLength : undefined;
+  const xofLen = typeof options === 'object' && options !== null ?
+    options.outputLength : undefined;
   if (xofLen !== undefined)
     validateUint32(xofLen, 'options.outputLength');
   this[kHandle] = new _Hash(algorithm, xofLen);

test/parallel/test-crypto-hash.js

@@ -191,6 +191,8 @@ common.expectsError(
   // Default outputLengths.
   assert.strictEqual(crypto.createHash('shake128').digest('hex'),
                      '7f9c2ba4e88f827d616045507605853e');
+  assert.strictEqual(crypto.createHash('shake128', null).digest('hex'),
+                     '7f9c2ba4e88f827d616045507605853e');
   assert.strictEqual(crypto.createHash('shake256').digest('hex'),
                      '46b9dd2b0ba88d13233b3feb743eeb24' +
                      '3fcd52ea62b81b82b50c27646ed5762f');