Apparatus and method for recording/reproducing information

An information playback device for executing data-playback processing from a recording medium, said information playback device comprising:

• cryptosystem-processing means which executes a process for decrypting content stored in the recording medium and which executes verification of an integrity check value (ICV) for digital-rights-management data (DRM) on content including use-restriction information on content;
• and
• a dedicated secret-information playback circuit which is used for a process for playing back the integrity check value (ICV) from a physically protected area on the recording medium and which is not used for a process for playing back the encrypted content.

An information recording medium on which content data capable of being played back is recorded, wherein an integrity check value (ICV) for digital-rights-management (DRM) data of content including use-restriction information on content is stored in a physically protected area on the recording medium.

An information recording method for executing data recording processing to a recording medium, said information recording method comprising:

• an encryption-processing step which generates encrypted content by executing a process for encrypting content to be stored in the recording medium and which generates an integrity check value (ICV) for digital-rights-management (DRM) data on content including use-restriction information on content;
• and
• a secret-information recording step which, by using a dedicated secret-information recording circuit, executes a process for recording the integrity check value (ICV) in a physically protected area on the recording medium.

An information playback method for executing data-playback processing from a recording medium, said information playback method comprising:

• a cryptosystem-processing step which executes a process for decrypting content stored in the recording medium and which executes verification of an integrity check value (ICV) for digital-rights-management data (DRM) on content including use-restriction information on content;
• and
• a secret information playback step which, by using a dedicated secret-information playback circuit, executes a process for playing back the integrity check value (ICV) from a physically protected area on the recording medium.