var override string
	if SignatureAlgorithm(e) == SHA1WithRSA || SignatureAlgorithm(e) == ECDSAWithSHA1 {
		override = " (temporarily override with GODEBUG=x509sha1=1)"
	}
	return fmt.Sprintf("x509: cannot verify signature: insecure algorithm %v", SignatureAlgorithm(e)) + override
}

// ConstraintViolationError results when a requested usage is not permitted by
// a certificate. For example: checking a signature when the public key isn't a

}

// typeAndHashFromSignatureScheme returns the corresponding signature type and
// crypto.Hash for a given TLS SignatureScheme.
func typeAndHashFromSignatureScheme(signatureAlgorithm SignatureScheme) (sigType uint8, hash crypto.Hash, err error) {
	switch signatureAlgorithm {
	case PKCS1WithSHA1, PKCS1WithSHA256, PKCS1WithSHA384, PKCS1WithSHA512:
		sigType = signaturePKCS1v15
	case PSSWithSHA256, PSSWithSHA384, PSSWithSHA512:

	}

	var signatureAlgorithm SignatureScheme
	var sigType uint8
	var sigHash crypto.Hash
	if ka.version >= VersionTLS12 {
		signatureAlgorithm, err = selectSignatureScheme(ka.version, cert, clientHello.supportedSignatureAlgorithms)
		if err != nil {
			return nil, err
		}
		sigType, sigHash, err = typeAndHashFromSignatureScheme(signatureAlgorithm)
		if err != nil {
			return nil, err
		}

				t.Fatalf("Failed to parse generated CRL: %s", err)
			}

			if tc.template.SignatureAlgorithm != UnknownSignatureAlgorithm &&
				parsedCRL.SignatureAlgorithm != tc.template.SignatureAlgorithm {
				t.Fatalf("SignatureAlgorithm mismatch: got %v; want %v.", parsedCRL.SignatureAlgorithm,
					tc.template.SignatureAlgorithm)
			}

			if len(tc.template.RevokedCertificates) > 0 {

	}

	// See RFC 8446, Section 4.4.3.
	if !isSupportedSignatureAlgorithm(certVerify.signatureAlgorithm, supportedSignatureAlgorithms()) {
		c.sendAlert(alertIllegalParameter)
		return errors.New("tls: certificate used with invalid signature algorithm")
	}
	sigType, sigHash, err := typeAndHashFromSignatureScheme(certVerify.signatureAlgorithm)
	if err != nil {
		return c.sendAlert(alertInternalError)
	}

			}
		})
	}
}

func generateJWT(key *jose.JSONWebKey, claims []byte) (string, error) {
	signer, err := jose.NewSigner(jose.SigningKey{
		Algorithm: jose.SignatureAlgorithm(key.Algorithm),
		Key:       key,
	}, nil)
	if err != nil {
		return "", fmt.Errorf("failed to create a signer: %v", err)
	}
	signature, err := signer.Sign(claims)
	if err != nil {

		var sigType uint8
		var sigHash crypto.Hash
		if c.vers >= VersionTLS12 {
			signatureAlgorithm, err := selectSignatureScheme(c.vers, chainToSend, certReq.supportedSignatureAlgorithms)
			if err != nil {
				c.sendAlert(alertIllegalParameter)
				return err
			}
			sigType, sigHash, err = typeAndHashFromSignatureScheme(signatureAlgorithm)
			if err != nil {
				return c.sendAlert(alertInternalError)
			}

		}

		// See RFC 8446, Section 4.4.3.
		if !isSupportedSignatureAlgorithm(certVerify.signatureAlgorithm, supportedSignatureAlgorithms()) {
			c.sendAlert(alertIllegalParameter)
			return errors.New("tls: client certificate used with invalid signature algorithm")
		}
		sigType, sigHash, err := typeAndHashFromSignatureScheme(certVerify.signatureAlgorithm)
		if err != nil {
			return c.sendAlert(alertInternalError)
		}

func loadRSAKey(t *testing.T, filepath string, alg jose.SignatureAlgorithm) *jose.JSONWebKey {
	return loadKey(t, filepath, alg, func(b []byte) (interface{}, error) {
		key, err := x509.ParsePKCS1PrivateKey(b)
		if err != nil {
			return nil, err
		}
		return key.Public(), nil
	})
}

func loadRSAPrivKey(t *testing.T, filepath string, alg jose.SignatureAlgorithm) *jose.JSONWebKey {

		if c.vers >= VersionTLS12 {
			if !isSupportedSignatureAlgorithm(certVerify.signatureAlgorithm, certReq.supportedSignatureAlgorithms) {
				c.sendAlert(alertIllegalParameter)
				return errors.New("tls: client certificate used with invalid signature algorithm")
			}
			sigType, sigHash, err = typeAndHashFromSignatureScheme(certVerify.signatureAlgorithm)
			if err != nil {
				return c.sendAlert(alertInternalError)
			}
		} else {