Systems and methods for securing cryptographic data using timestamps

摘要

Systems and methods for authenticating playback devices using timestamp validation in accordance with embodiments of the invention are disclosed. One embodiment includes securely storing at least one timestamp in memory within a playback device in response to the occurrence of at least one predetermined event, where a stored timestamp is based on the current time of a system clock when an event occurs, generating a cryptographic key using the at least one timestamp, securing cryptographic data using the cryptographic key, receiving a request to playback encrypted content, where the encrypted content is accessible using the cryptographic data, accessing the at least one timestamp, generating the cryptographic key, accessing the cryptographic data using at least the cryptographic key, and playing back the content using the playback device.

主权项

1. A method of securing cryptographic data used to playback encrypted content on a playback device, the method comprising:
securely storing at least one timestamp in memory within a playback device in response to the occurrence of at least one predetermined event, where a stored timestamp is based on the current time of a system clock within the playback device when a predetermined event occurs, where the at least one timestamp is secured using at least a product key derived from product provisioning characteristics, and where the predetermined event arises from a playback event of a specific piece of content by the playback device; generating a cryptographic key using information including the at least one time stamp; securing cryptographic data used to playback encrypted content on the playback device using the cryptographic key; receiving a request to playback encrypted content via a user interface on the playback device, where the encrypted content is accessible using the cryptographic data securely stored in the memory of the playback device; accessing the at least one timestamp securely stored in memory using the playback device; deleting the cryptographic data from memory, when the system clock is invalid; generating the cryptographic key using information including the at least one retrieved time stamp; decrypting the cryptographic data using at least the cryptographic key generated using information including the at least one retrieved timestamp; decrypting at least a portion of the encrypted content using the cryptographic data; and playing back the content using the playback device.