context string) ([]byte, error) { fipsSelfTest() fips140.RecordApproved() if l := len(message); l != sha512Size { return nil, errors.New("ed25519: bad Ed25519ph message hash length: " + strconv.Itoa(l)) } if l := len(context); l > 255 { return nil, errors.New("ed25519: bad Ed25519ph context length: " + strconv.Itoa(l)) } return signWithDom(signature, priv, message, domPrefixPh, context), nil } func SignCtx(priv *PrivateKey, message []byte, context string) ([]byte, error) { // Outline the function body...