Algorithm:  details.oid,
				Parameters: details.params,
			}, nil
		}
	}

	return 0, ai, errors.New("x509: unknown SignatureAlgorithm")
}

func signTBS(tbs []byte, key crypto.Signer, sigAlg SignatureAlgorithm, rand io.Reader) ([]byte, error) {
	signed := tbs
	hashFunc := sigAlg.hashFunc()
	if hashFunc != 0 {
		h := hashFunc.New()
		h.Write(signed)