Security chip used in a contents data playing device, update management method, and update management program

摘要

A security chip is used in a contents data playing device. The security chip includes a storage unit configured to store firmware data including a firmware program, and a firmware update management unit configured to determine whether an update process is to be executed on the firmware data based on a comparison between expiration information set for the firmware data and time information received via a network, in response to a request input to the security chip to acquire a contents key or to decrypt contents data, and to reject the request when the update process is to be executed. The firmware program causes the security chip to function as a contents key acquisition control unit configured to acquire, via the network, the contents key for decrypting the contents data, and a decryption unit configured to decrypt the contents data by using the contents key.

主权项

1. A security chip used in a contents data playing device, the security chip comprising:
at least one hardware processor; and a memory configured to store firmware data including a firmware update program and a firmware program; the firmware update program causes the processor to: determine whether an update process has been completed on the firmware data when a contents key acquisition instruction or a contents data playing instruction is input to the contents data playing device, initiate a determination process to determine whether the firmware data needs to be updated based on a comparison between expiration information set in the firmware data and time information received via a network, the time information being encrypted together with a contents key; decrypt the encrypted time information and confirm that the time information has not been hampered; in response to a verification that an update process has been completed and a predetermined period has elapsed according to the comparison, determine that the updating of the firmware data is needed;
reject the contents key acquisition instruction or the contents data playing instruction when the firmware data needs to be updated; and in response to the verification that an update process has been completed and a predetermined period has not elapsed according to the comparison, determine that the updating of the firmware data is not needed;
acquire, via the network, the contents key for decrypting contents data, anddecrypt the contents data by using the contents key.