# US 2008/0189794 A1 · Secure Host Interface > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0189794 A1 - Document ID: US20080189794A1 - Status: Published application - Kind: A1 - Application number: 11/814,010 - Filed: 2006-01-13 - Published: 2008-08-07 - Earliest claimed: 2005-01-18 - Assignees: Koninklijke Philips Electronics N.V. - Inventors: Antonius Adriaan Maria Staring; Johan Cornelis Talstra - Web page: https://patentgrep.com/patent/US20080189794A1 ## CPC - G11B 20/00086: {Circuits for prevention of unauthorised reproduction or copying, e.g. piracy (indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00)} - G06F 21/10: Protecting distributed programs or content, e.g. vending or licensing of copyrighted material (protection in video systems or pay television H04N7/16) {; Digital rights management [DRM]} - H04L 9/3273: {for mutual authentication (network architectures or network communication protocols for achieving mutual authentication in a packet data network H04L63/0869)} - H04L 63/0428: {wherein the data content is protected, e.g. by encrypting or encapsulating the payload} - H04L 63/06: {for supporting key management in a packet data network (cryptographic mechanisms or cryptographic arrangements for key management H04L9/08)} - G06F 2221/2103: Challenge-response - H04L 2209/603: Digital right managament [DRM] - H04L 2209/605: Copy protection - H04L 2463/101: applying security measures for digital rights management - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract 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. ## Claims ### Claim at position 1 1-15. (canceled) ### Claim 16 Application unit (1, 21, 41) for use in a digital rights management system (40) comprising a drive unit (3, 23, 43) for controlling access rights to copy protected content, said application unit (1, 21, 41) comprising: 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) indicating that said request has been carried out. ### Claim 17 (depends on 16) Application unit (1, 21, 41) as claimed in claim 16, wherein said request generation unit (47) is adapted for cryptographically linking said message and said challenge (RX) by means of said bus key (KB). ### Claim 18 (depends on 16) Application unit (1, 21, 41) as claimed in claim 16, wherein said request generation unit (47) is adapted for including a signature (sig) into said request (7) for use in an integrity test of said request (7). ### Claim 19 (depends on 16) Application unit (1, 21, 41) as claimed in claim 16, wherein said request generation unit (47) is adapted for encrypting said request (7, 27) using said bus key (KB). ### Claim 20 (depends on 16) Application unit (1, 21, 41) as claimed in claim 16, wherein said request generation unit (47) is adapted for including a value derived from said challenge (RX) and/or said message and said bus key (KB) by means of a hash function, in particular by means of a keyed-hash function using said bus key (KB), into said request (7, 27). ### Claim 21 (depends on 16) Application unit (1, 21, 41) as claimed in claim 16, wherein said message includes a command for managing hidden channel entries, in particular a command for reading a hidden channel entry, for changing a hidden channel entry and/or for wiping a hidden channel entry. ### Claim 22 (depends on 16) Application unit (1, 21, 41) as claimed in claim 16, wherein said request generation unit (47) is adapted for including a random number, an identifier identifying said request (7, 27), in particular a unique identifier, and/or predetermined data as said challenge (RX) into said request (7, 27). ### Claim 23 (depends on 16) Application unit (1, 21, 41) as claimed in claim 16, wherein said application unit (1, 21, 41) is a host, in particular a software application. ### Claim 24 Drive unit (3, 23, 43) for use in a digital rights management system (40) comprising an application unit (1, 21, 41) for controlling access rights to copy protected content, said drive unit (3, 23, 43) comprising: a key storage unit (55) for storing a bus key (KB), a communication unit (51) for receiving a request (7, 27) to be carried out by said drive unit 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) 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. ### Claim 25 (depends on 24) Drive unit (3, 23, 43) as claimed in claim 24, wherein said reply includes a hidden channel entry, in particular a hidden channel entry read or changed by said drive unit. ### Claim 26 (depends on 24) Digital rights management system (40) for controlling access rights to copy protected content comprising an application unit (1, 21, 41) for use in a digital rights management system (40) comprising a drive unit (3, 23, 43) for controlling access rights to copy protected content, said application unit (1, 21, 41) comprising: 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) indicating that said request has been carried out and a drive unit (3, 23, 43) as claimed in claim 24, wherein said bus key (KB) is shared by said application unit (1, 21, 41) and said drive unit (3, 23, 43). ### Claim 27 Digital rights management method for controlling access rights to copy protected content in a digital rights management system (40) comprising an application unit (1, 21, 41) and a drive unit (3, 23,43) sharing a bus key (KB), said method comprising the steps of: a) generating (5, 25), by said application unit (1, 21, 41), a request (7, 27) to be carried out by said drive unit including a message regarding said access rights and a challenge (RX), b) communicating said request (7, 27) from said application unit (1, 21, 41) to said drive unit (3, 23,43), c) processing (11, 31) said message by said drive unit (3, 23,43), d) generating, by said drive unit (3, 23,43), a 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 together by means of said bus key (KB), e) communicating said response (13, 33) from said drive unit (3, 23, 43) to said application unit (1, 21, 41), and f) verifying (15, 35), by said application unit (1, 21, 41), a link between said request (7, 27) and said response (13, 33) by decoding said response using said bus key (KB) and by checking for the presence of an indication of said challenge (RX) in said response (13, 33) indicating that said request has been carried out by said drive unit (3, 23,43). ### Claim 28 Digital rights management method, further comprising a step of verifying (9, 29) said request (7, 27) after step b) and before step c). ### Claim 29 (depends on 27) A computer program comprising computer program code means for causing an application unit (1, 21, 41) in a digital rights management system (40), further comprising a drive unit (3, 23,43) sharing a bus key (KB) with said application unit to perform the following steps of a method as claimed in claim 27 when said computer program is run on said application unit: generating (5, 25) a request (7, 27) to be carried out by said drive unit including a message regarding said access rights and a challenge (RX), communicating said request (7, 27) from said application unit (1, 21, 41) to said drive unit (3, 23,43), said drive unit being adapted to process (11, 31) said message, to generate a 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 together by means of said bus key (KB), and to communicate said response (13, 33) from said drive unit (3, 23, 43) to said application unit (1, 21, 41), and verifying (15, 35) a link between said request (7, 27) and said response (13, 33) by decoding said response using said bus key (KB) and by checking for the presence of an indication of said challenge (RX) in said response (13, 33) indicating that said request has been carried out by said drive unit (3, 23,43). ### Claim 30 (depends on 27) A computer program comprising computer program code means for causing a drive unit (3, 23,43) in a digital rights management system (40), further comprising an application unit (1, 21, 41) sharing a bus key (KB) with said drive unit, to perform the following steps of a method as claimed in claim 27 when said computer program is run on said drive unit: receiving a request (7, 27) from said application unit (1, 21, 41), said request being generated by said application unit (1, 21, 41) for being carried out by said drive unit including a message regarding said access rights and a challenge (RX), processing (11, 31) said message, generating a 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 together by means of said bus key (KB), communicating said response (13, 33) from said drive unit (3, 23, 43) to said application unit (1, 21, 41) for verifying (15, 35) a link between said request (7, 27) and said response (13, 33) by decoding said response using said bus key (KB) and by checking for the presence of an indication of said challenge (RX) in said response (13, 33) indicating that said request has been carried out by said drive unit (3, 23,43).