Contents recorder/reproducer

摘要

A unidirectional function circuit generates a first encryption key according to the device identification information stored in a device identification information holding unit. Another unidirectional function circuit generates a second encryption key that depends on a write block address. A contents key generator generates a contents key using the first encryption key, second encryption key, and relation information. An encryptor records contents, which are encrypted using the contents key, onto a HDD.