EC_STRUCTURED_PRIV_KEY_MAX_EXPORT_SIZE
#if (EC_STRUCTURED_PRIV_KEY_MAX_EXPORT_SIZE > 255)
u8 priv_key_buf[EC_STRUCTURED_PRIV_KEY_MAX_EXPORT_SIZE];
u8 export_buf_size, priv_key_buf[EC_STRUCTURED_PRIV_KEY_MAX_EXPORT_SIZE];
u8 priv_key_buf[EC_STRUCTURED_PRIV_KEY_MAX_EXPORT_SIZE];