cert, certErr := util.ParsePemEncodedCertificate(certBytes)
	if certErr != nil {
		return time.Duration(0), certErr
	}
	timeToExpire := cert.NotAfter.Sub(now)
	if timeToExpire < 0 {
		return time.Duration(0), fmt.Errorf("certificate already expired at %s, but now is %s",
			cert.NotAfter, now)
	}

			}
			cert, certErr := util.ParsePemEncodedCertificate(rotatedCertBytes)
			if certErr != nil {
				t.Fatalf("rotated cert is not valid")
			}
			currTime := time.Now()
			timeToExpire := cert.NotAfter.Sub(currTime)
			if timeToExpire < 0 {
				t.Fatalf("rotated cert is already expired")
			}
		})
	}
}

func checkCert(t *testing.T, s *Server, cert, key []byte) bool {
	t.Helper()