(45) If the processing is carried out for the purpose of fulfilling a legal obligation to which the controller is subject, or if it is necessary for the performance of a task carried out in the public interest or in the exercise of public authority, Union law or the law of a Member State should provide the basis for the processing. This regulation does not require that there be a specific legal regulation for each individual processing. It may be sufficient that the regulation in question is the basis for various processing operations arising from a legal obligation to which the controller is subject, or that the processing is necessary for the performance of a task carried out in the public interest or in the exercise of official authority. Union or member state law should also specify the purpose of the processing. In addition, the law may further specify the general conditions set forth in this Regulation regarding the lawfulness of the processing, specify ways to identify the controller, the type of personal data to be processed, the data subjects, the entities to which the personal data may be disclosed, purpose limitation, retention period and other measures to ensure the lawfulness and fairness of the processing. Union or Member State law should also specify whether the controller performing a task carried out in the public interest or in the exercise of public authority should be a public authority or another natural or legal person subject to public law or private law, such as a professional association, if the public interest justifies it, including health objectives such as public health, social protection and management of health care services.