Authentication engine and stream cipher engine sharing in digital content protection architectures

摘要

A system for receiving and decrypting media content encrypted according to the HDCP protocol is described herein. A receiving device coupled to a plurality of content channels includes an authentication engine to authenticate each content channel and to generate an initial session key associated with each authenticated content channel. The content channels can be, for example, an HDMI channel or an MHL3 channel. A session key indicator indicating a session key used to encrypt media content is received, and an updated session key is generated. The receiving device also includes a stream cipher engine configured to decrypt received encrypted media content using the updated session key. Decrypted media content can then be displayed, for instance on a display of the receiving device.

主权项

1. An apparatus comprising:
a plurality of content channel inputs, each content channel input corresponding to a content channel and an associated transmitting device, each transmitting device configured to encrypt media content according to the High-Definition Content Protection (HDCP) protocol and to provide the encrypted media content to the corresponding content channel input via the associated content channel; an authentication engine implemented by a hardware processor and configured to sequentially authenticate each content channel and, for each authenticated content channel, to generate an initial session key corresponding to the authenticated content channel; a session key indicator input configured to receive a session key indicator from a transmitting device associated with an active content channel providing encrypted media content comprising a current encrypted frame, the session key indicator representative of a current session key used to encrypt the current encrypted frame; a session key engine configured to generate the current session key based on the received session key indicator and the initial session key corresponding to the active content channel; and a stream cipher engine configured to decrypt the encrypted media content using at least the generated current session key.