node/test/sequential/test-crypto-timing-safe-equal.js

'use strict';
const common = require('../common');
if (!common.hasCrypto)
  common.skip('missing crypto');

const assert = require('assert');
const crypto = require('crypto');

// 'should consider equal strings to be equal'
assert.strictEqual(
  crypto.timingSafeEqual(Buffer.from('foo'), Buffer.from('foo')),
  true
);

// 'should consider unequal strings to be unequal'
assert.strictEqual(
  crypto.timingSafeEqual(Buffer.from('foo'), Buffer.from('bar')),
  false
);

{
  // Test TypedArrays with different lengths but equal byteLengths.
  const buf = crypto.randomBytes(16).buffer;
  const a1 = new Uint8Array(buf);
  const a2 = new Uint16Array(buf);
  const a3 = new Uint32Array(buf);

  for (const left of [a1, a2, a3]) {
    for (const right of [a1, a2, a3]) {
      assert.strictEqual(crypto.timingSafeEqual(left, right), true);
    }
  }
}

common.expectsError(
  () => crypto.timingSafeEqual(Buffer.from([1, 2, 3]), Buffer.from([1, 2])),
  {
    code: 'ERR_CRYPTO_TIMING_SAFE_EQUAL_LENGTH',
    type: RangeError,
    message: 'Input buffers must have the same byte length'
  }
);

common.expectsError(
  () => crypto.timingSafeEqual('not a buffer', Buffer.from([1, 2])),
  {
    code: 'ERR_INVALID_ARG_TYPE',
    type: TypeError,
    message:
      'The "buf1" argument must be one of type Buffer, TypedArray, or ' +
      'DataView. Received type string'
  }
);

common.expectsError(
  () => crypto.timingSafeEqual(Buffer.from([1, 2]), 'not a buffer'),
  {
    code: 'ERR_INVALID_ARG_TYPE',
    type: TypeError,
    message:
      'The "buf2" argument must be one of type Buffer, TypedArray, or ' +
      'DataView. Received type string'
  }
);