// is used then an error is returned
func GetEllipticCurve(privKey *crypto.PrivateKey) (elliptic.Curve, error) {
	switch key := (*privKey).(type) {
	// this should agree with var SupportedECSignatureAlgorithms
	case *ecdsa.PrivateKey:
		if key.Curve == elliptic.P384() {
			return key.Curve, nil
		}
		return elliptic.P256(), nil
	default:
		return nil, fmt.Errorf("private key is not ECDSA based")
	}

			}
		})
	}
}

func createFakeCsr(t *testing.T) []byte {
	options := pkiutil.CertOptions{
		Host:       testCsrHostName,
		RSAKeySize: 2048,
		PKCS8Key:   false,
		ECSigAlg:   pkiutil.SupportedECSignatureAlgorithms("ECDSA"),
	}
	csrPEM, _, err := pkiutil.GenCSR(options)
	if err != nil {
		t.Fatalf("Error creating Mock CA client: %v", err)
		return nil
	}
	return csrPEM
}