SECURE HOST INTERFACE

摘要

The present invention relates to a digital rights management system (40) for controlling access rights to copy protected content comprising an application unit (1, 21, 41) and a drive unit (3, 23, 43), to an application unit (1, 21, 41), to a drive unit (3, 23, 43) and to a corresponding digital rights management method. In order to allow an increased security in the management of digital rights, wherein in particular a "filter-driver"-hack is made impossible or is at least substantially complicated and a reliable confirmation about a command given in respect of digital rights and its execution, a digital rights management system (40) is proposed wherein said application unit (1, 21, 41) comprises a key storage unit (45) for storing a bus key (KB), a request generation unit (47) for generating a request (7, 27) to be carried out by said drive unit including a message regarding said access rights and a challenge (RX), a communication unit (51) for transmitting said request (7, 27) and for receiving a response (13, 33) to said request (7, 27) from said drive unit (3, 23, 43), a response verification unit (49) for verifying a link between said request (7, 27) and said response (13, 33) by decoding said response (13, 33) using said bus key (KB) and by checking for the presence of an indication of said challenge (RX) in said response (13, 33) and said drive unit (3, 23, 43) comprises a key storage unit (55) for storing a bus key (KB), a communication unit (51) for receiving a request (7, 27) including a message regarding said access rights and a challenge (RX) from said application unit (1, 21, 41) and for transmitting a response (13, 33) to said request (1, 21, 41), a request processing unit (57) for verifying said request (7, 27) and processing said message, a response generation unit (59) for generating said response (13, 33) including an indication of said challenge (RX) and a reply to said message, wherein said indication of said challenge (RX) and said reply are cryptographically linked by means of said bus key (KB) and wherein indication of said challenge (RX) in said response (13, 33) indicates that said request has been carried out.