In an information processing apparatus, a key management unit forms a
judgment as to whether an authentication key owned by an application
program is valid or invalid. A content protection unit is controlled
based on this determination so that contents are exchanged between the
information processing apparatus and the application program. An
encryption/decryption unit encrypts a decrypted content by using an
encryption key received from a key management unit and outputs the
encrypted content to an encrypted-information addition unit. The
encrypted-information addition unit adds encrypted information to the
encrypted content received from the encryption/decryption unit and
outputs the encrypted content with the encrypted information added
thereto to the application program. As a result, it is possible to
prevent content from being utilized illegally.