crypto: migrate timingSafeEqual to internal/errors

PR-URL: https://github.com/nodejs/node/pull/16448
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>

3 files changed, 24 insertions, 2 deletions

diff --git a/lib/crypto.js b/lib/crypto.js
index 1337cccf2c..0082172c5c 100644
--- a/lib/crypto.js
+++ b/lib/crypto.js
@@ -34,7 +34,6 @@ const constants = process.binding('constants').crypto;
 const {
   getFipsCrypto,
   setFipsCrypto,
-  timingSafeEqual
 } = process.binding('crypto');
 const {
   randomBytes,
@@ -75,6 +74,7 @@ const {
   getHashes,
   setDefaultEncoding,
   setEngine,
+  timingSafeEqual,
   toBuf
 } = require('internal/crypto/util');
 const Certificate = require('internal/crypto/certificate');
diff --git a/lib/internal/crypto/util.js b/lib/internal/crypto/util.js
index 84ad1fb2c7..ac01a447bc 100644
--- a/lib/internal/crypto/util.js
+++ b/lib/internal/crypto/util.js
@@ -4,7 +4,8 @@ const {
   getCiphers: _getCiphers,
   getCurves: _getCurves,
   getHashes: _getHashes,
-  setEngine: _setEngine
+  setEngine: _setEngine,
+  timingSafeEqual: _timingSafeEqual
 } = process.binding('crypto');
 
 const {
@@ -17,6 +18,9 @@ const {
   cachedResult,
   filterDuplicateStrings
 } = require('internal/util');
+const {
+  isArrayBufferView
+} = require('internal/util/types');
 
 var defaultEncoding = 'buffer';
 
@@ -60,6 +64,21 @@ function setEngine(id, flags) {
     throw new errors.Error('ERR_CRYPTO_ENGINE_UNKNOWN', id);
 }
 
+function timingSafeEqual(a, b) {
+  if (!isArrayBufferView(a)) {
+    throw new errors.TypeError('ERR_INVALID_ARG_TYPE', 'a',
+                               ['Buffer', 'TypedArray', 'DataView']);
+  }
+  if (!isArrayBufferView(b)) {
+    throw new errors.TypeError('ERR_INVALID_ARG_TYPE', 'b',
+                               ['Buffer', 'TypedArray', 'DataView']);
+  }
+  if (a.length !== b.length) {
+    throw new errors.RangeError('ERR_CRYPTO_TIMING_SAFE_EQUAL_LENGTH');
+  }
+  return _timingSafeEqual(a, b);
+}
+
 module.exports = {
   getCiphers,
   getCurves,
@@ -67,5 +86,6 @@ module.exports = {
   getHashes,
   setDefaultEncoding,
   setEngine,
+  timingSafeEqual,
   toBuf
 };
diff --git a/lib/internal/errors.js b/lib/internal/errors.js
index e211333648..48eb6b8935 100644
--- a/lib/internal/errors.js
+++ b/lib/internal/errors.js
@@ -160,6 +160,8 @@ E('ERR_CRYPTO_HASH_FINALIZED', 'Digest already called');
 E('ERR_CRYPTO_HASH_UPDATE_FAILED', 'Hash update failed');
 E('ERR_CRYPTO_INVALID_DIGEST', 'Invalid digest: %s');
 E('ERR_CRYPTO_SIGN_KEY_REQUIRED', 'No key provided to sign');
+E('ERR_CRYPTO_TIMING_SAFE_EQUAL_LENGTH',
+  'Input buffers must have the same length');
 E('ERR_DNS_SET_SERVERS_FAILED', (err, servers) =>
   `c-ares failed to set servers: "${err}" [${servers}]`);
 E('ERR_ENCODING_INVALID_ENCODED_DATA',