crypto: do not add undefined hash in webcrypto normalizeAlgorithm

nodejs · Apr 1, 2022 · df21856 · df21856
1 parent 8dbdca8
commit df21856
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Showing 3 changed files with 47 additions and 14 deletions.
diff --git a/lib/internal/crypto/util.js b/lib/internal/crypto/util.js
@@ -206,35 +206,43 @@ function validateMaxBufferLength(data, name) {
   }
 }
 
-function normalizeAlgorithm(algorithm, label = 'algorithm') {
+function validateAlgorithmName(name) {
+  if (typeof name !== 'string' ||
+      !ArrayPrototypeIncludes(
+        kAlgorithmsKeys,
+        StringPrototypeToLowerCase(name))) {
+    throw lazyDOMException('Unrecognized name.', 'NotSupportedError');
+  }
+}
+
+function normalizeAlgorithm(algorithm) {
   if (algorithm != null) {
     if (typeof algorithm === 'string')
       algorithm = { name: algorithm };
 
     if (typeof algorithm === 'object') {
       const { name } = algorithm;
-      let hash;
-      if (typeof name !== 'string' ||
-          !ArrayPrototypeIncludes(
-            kAlgorithmsKeys,
-            StringPrototypeToLowerCase(name))) {
-        throw lazyDOMException('Unrecognized name.', 'NotSupportedError');
-      }
-      if (algorithm.hash !== undefined) {
-        hash = normalizeAlgorithm(algorithm.hash, 'algorithm.hash');
+      validateAlgorithmName(name);
+      let { hash } = algorithm;
+      if (hash !== undefined) {
+        hash = normalizeAlgorithm(hash);
         if (!ArrayPrototypeIncludes(kHashTypes, hash.name))
           throw lazyDOMException('Unrecognized name.', 'NotSupportedError');
       }
-      return {
+      const normalized = {
         ...algorithm,
         name: kAlgorithms[StringPrototypeToLowerCase(name)],
-        hash,
       };
+      if (hash) {
+        normalized.hash = hash;
+      }
+      return normalized;
     }
   }
   throw lazyDOMException('Unrecognized name.', 'NotSupportedError');
 }
 
+
 function hasAnyNotIn(set, checks) {
   for (const s of set)
     if (!ArrayPrototypeIncludes(checks, s))

diff --git a/lib/internal/crypto/webcrypto.js b/lib/internal/crypto/webcrypto.js
@@ -557,10 +557,10 @@ async function unwrapKey(
   extractable,
   keyUsages) {
   wrappedKey = getArrayBufferOrView(wrappedKey, 'wrappedKey');
-
+  unwrapAlgo = normalizeAlgorithm(unwrapAlgo);
   let keyData = await cipherOrWrap(
     kWebCryptoCipherDecrypt,
-    normalizeAlgorithm(unwrapAlgo),
+    unwrapAlgo,
     unwrappingKey,
     wrappedKey,
     'unwrapKey');

diff --git a/test/parallel/test-webcrypto-utils.js b/test/parallel/test-webcrypto-utils.js
@@ -0,0 +1,25 @@
+// Flags: --expose-internals
+'use strict';
+
+const common = require('../common');
+if (!common.hasCrypto)
+  common.skip('missing crypto');
+
+const assert = require('assert');
+
+const {
+  normalizeAlgorithm,
+} = require('internal/crypto/util');
+
+{
+  // Check that normalizeAlgorithm does not add an undefined hash property
+  assert.strictEqual('hash' in normalizeAlgorithm({ name: 'ECDH' }), false);
+  assert.strictEqual('hash' in normalizeAlgorithm('ECDH'), false);
+}
+
+{
+  // Check that normalizeAlgorithm does not mutate object inputs
+  const algorithm = { name: 'ECDH', hash: 'SHA-256' };
+  assert.strictEqual(normalizeAlgorithm(algorithm) !== algorithm, true);
+  assert.deepStrictEqual(algorithm, { name: 'ECDH', hash: 'SHA-256' });
+}