// system (crypto/rand) is used.
func GenerateKey(extKey []byte, random io.Reader) (key ObjectKey) {
	if random == nil {
		random = rand.Reader
	}
	if len(extKey) != 32 { // safety check
		logger.CriticalIf(context.Background(), errors.New("crypto: invalid key length"))
	}
	var nonce [32]byte
	if _, err := io.ReadFull(random, nonce[:]); err != nil {

		timeout := atomic.LoadInt64(&dt.timeout) * 125 / 100

		// Set upper cap.
		if timeout > int64(maxDynamicTimeout) {
			timeout = int64(maxDynamicTimeout)
		}
		// Safety, shouldn't happen
		if timeout < dt.minimum {
			timeout = dt.minimum
		}
		atomic.StoreInt64(&dt.timeout, timeout)
	} else if failPct < dynamicTimeoutDecreaseThresholdPct {