Patent ID: 8908860

Claim:
An information processing device, comprising: data processing circuitry configured to: execute decryption and playing-processing of an encrypted content; execute encrypted-content-playback-propriety-determination processing by applying an encrypted-content-signature file set for the encrypted content; wherein the encrypted-content-signature file includes: a content-hash-list-group including at least one first hash value based on configuration data of the encrypted content, and signature data including data generated from a content-encryption-key and from the content-hash-list-group; execute, as part of the encrypted-content-playback-propriety-determination processing, hash-value-matching processing between at least one second hash value calculated from the configuration data, and the at least one first hash value included in the content-hash-list-group, and signature-verification processing of the signature data in the encrypted-content-signature file; and permit the decryption and playing-processing only if both of the hash-value-matching processing and the signature-verification processing are successful, wherein the data processing circuitry is further configured to execute, as part of the encrypted content playback propriety determination processing, hash-value-replacement processing for replacing the at least one first hash value included in the content-hash-list-group with at least one second hash value calculated from the configuration data, and signature-verification processing of the signature data in the encrypted content signature file by applying concatenated data of only the content hash list group subjected to the hash value replacement processing, and another hash value of the content-encryption-key.