Apparatus and method for preventing unauthorized use of information recorded on an information recording medium

• US 6,289,102 B1
• Filed: 10/01/1997
• Issued: 09/11/2001
• Est. Priority Date: 10/09/1995
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Ueda, Hiroshi, Tatebayashi, Makoto, Fukushima, Yoshihisa, Ito, Motoshi, Matsuzaki, Natsume
• Primary Examiner(s): Powell, Mark R.
• Application Number:
  US08/849,785
• Time in Patent Office: 1,441 Days
• Field of Search: 713/100, 360/69, 380/21, 380/22, 380/3, 380/4, 380/201
• US Class Current: 380/201
• CPC Class Codes: G06F 2211/007 Encryption, En-/decode, En-/decipher, En-/decypher, Scramble, (De-)compress
• CPC Class Codes: G11B 19/02 Control of operating function, e.g. switching from recording to reproducing
• CPC Class Codes: G11B 19/04 Arrangements for preventing, inhibiting, or warning against double recording on the same blank or against other recording or reproducing malfunctions
• CPC Class Codes: G11B 19/12 by sensing distinguishing features of or on records, e.g. diameter end mark
• CPC Class Codes: 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
• CPC Class Codes: G11B 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00449 content scrambling system [CSS]
• CPC Class Codes: G11B 20/00507 wherein consecutive physical data units of the record carrier are encrypted with separate encryption keys, e.g. the key changes on a cluster or sector basis
• CPC Class Codes: G11B 20/00514 wherein the entire content is encrypted with the same key, e.g. disc key or master key
• CPC Class Codes: G11B 20/00528 wherein each title is encrypted with a separate encryption key for each title, e.g. title key for movie, song or data file
• CPC Class Codes: G11B 20/00557 wherein further management data is encrypted, e.g. sector headers, TOC or the lead-in or lead-out areas
• CPC Class Codes: G11B 20/00768 wherein copy control information is used, e.g. for indicating whether a content may be copied freely, no more, once, or never, by setting CGMS, SCMS, or CCI flags
• CPC Class Codes: G11B 20/1217 on discs
• CPC Class Codes: G11B 2220/213 Read-only discs
• CPC Class Codes: G11B 2220/2545 CDs
• CPC Class Codes: G11B 2220/2562 DVDs [digital versatile discs]; Digital video discs; MMCDs; HDCDs
• CPC Class Codes: G11B 27/034 on discs G11B27/036, G11B27/038 take precedence
• CPC Class Codes: G11B 27/105 of operating discs
• CPC Class Codes: H04N 2005/91321 the copy protection signal being a copy protection control signal, e.g. a record inhibit signal
• CPC Class Codes: H04N 2005/91328 the copy protection signal being a copy management signal, e.g. a copy generation management signal [CGMS]
• CPC Class Codes: H04N 2005/91364 : the video signal being scrambled
• CPC Class Codes: H04N 5/85 : on discs or drums
• CPC Class Codes: H04N 5/913 : for scrambling ; for copy protection
• CPC Class Codes: H04N 9/8042 : involving data reduction

Abstract

An information recording medium includes a lead-in area and a data recording area. Key information is recorded in the lead-in area. Scrambled data is recorded in the data recording area. The scrambled data is descrambled based on the key information.

Claims

1. An information recording medium comprising a lead-in area not accessible by devices other than a disk reproducing device and a data recording area, wherein

key information is recorded in the lead-in area,

scrambled data is recorded in the data recording area, and

the scrambled data is descrambled based on the key information.

2. An information recording medium comprising a lead-in area not accessible by devices other than a disk reproducing device and a data recording area, wherein

first key information is recorded in the lead-in area,

a plurality of second key information and scrambled data are recorded in the data recording area, and

a portion of the scrambled data is descrambled based on information obtained by converting one of the plurality of second key information based on the first key information.

3. An information recording medium according to claim 2, wherein the data recording area is divided into a plurality of sectors, each of the plurality of sectors including a sector header field not accessible by devices other than a disk reproducing device where information for identifying the sector is recorded and a main data field where the portion of the scrambled data is recorded, and a unique second key information is recorded in each sector header field for descrambling the portion of the scrambled data in the respective sector header field.

4. An information recording medium according to claim 2, wherein the first key information is encrypted information, the second key information is encrypted information which has been encrypted based on the first key information, and the information for descrambling the portion of the scrambled data is obtained by decrypting the second key information.

5. An information recording medium according to claim 4, wherein the first key information is encrypted by master key information.

6. An information recording medium according to claim 4, wherein a plurality of first key information are recorded in the lead-in area, each of the plurality of first key information is encrypted information, and the plurality of first key information are obtained by encrypting the same key information by a plurality of different master key information.

7. An information recording medium according to claim 2, wherein a scramble flag for indicating whether or not data recorded in the data recording area is scrambled is further recorded in the information recording medium.

8. An information recording medium according to claim 7, wherein the data recording area is divided into a plurality of sectors, each of the plurality of sectors including a sector header field not accessible by devices other than a disk reproducing device where information for identifying the sector is recorded and a main data field where the scrambled data is recorded, and the scramble flag is recorded in the sector header field.

9. An information recording medium according to claim 7, wherein the data recording area includes an area where a plurality of files are recorded and a file management area where information for managing the plurality of files is recorded, and the scramble flag is recorded in the file management area.

10. An information recording medium according to claim 2, wherein mutual authentication key information for performing mutual authentication between a reading device for reading the scrambled data and a decoding device including a descramble circuit for descrambling the scrambled data is further recorded in the lead-in area.

11. An information recording. medium according to claim 2, wherein the first key information indicates one of a plurality of tables each of the plurality of tables includes a plurality of bit strings, each of the plurality of bit strings identifies an initial value for generating a pseudo-random number sequence, the second key information indicates one of the plurality of bit strings included in the table indicated by the first key information, and the scrambled data is descrambled by performing a logical operation to the pseudo- random number sequence.

12. An information recording medium according to claim 2, wherein the data recording area is divided into a plurality of sectors, each of the plurality of sectors including a sector header field not accessible by devices other than a disk reproducing device where information for identifying the sector is recorded and a main data field where the scrambled data is recorded, and information for identifying use of the information recording medium is recorded in the sector header field.

13. An information reproducing device comprising:

a reading circuit for reading scrambled data and key information to be used for descrambling the scrambled data from an information recording medium; and

an authentication circuit for authenticating to transmit information corresponding to the key information to the decoding device before transmitting the scrambled data to the decoding device including a descramble circuit for descrambling the scrambled data.

14. An information reproducing device according to claim 13,

wherein the information recording medium includes a lead-in area not accessible by devices other than a disk reproducing device and a data s recording area,

the key information includes first key information recorded in the lead-in area and second key information recorded in the data recording area, and

the lead-in area includes mutual authentication information for use by the authentication circuit.

15. An information reproducing device according to claim 13, wherein authentication by the authentication circuit is performed by using information changing over time.

16. An information reproducing device comprising:

an authentication circuit for authenticating to receive information corresponding to key information from a reading device before receiving scrambled data from the reading device for reading the scrambled data and the key information to be used for descrambling the scrambled data from an information recording medium; and

a descramble circuit for descrambling the scrambled data received from the reading device.

17. An information reproducing device according to claim 16,

wherein the information recording medium includes a lead-in area not accessible by devices other than a disk reproducing device and a data recording area,

the key information includes first key information recorded in the lead-in area and second key information recorded in the data recording area, and

the lead-in area includes mutual authentication information for use by the authentication circuit.

18. An information reproducing device according to claim 17, wherein the descramble circuit descrambles the scrambled data based on information obtained by converting the second key information based on the first key information.

19. An information reproducing device according to claim 16, wherein authentication by the authentication circuit is performed by using information changing over time.

20. An information reproducing device comprising:

a reading circuit for reading scrambled data and key information to be used for descrambling the scrambled data from an information recording medium;

a decoding section including a descramble circuit for descrambling the scrambled data; and

an authentication circuit for authenticating to transmit information corresponding to the key information to the decoding section before transmitting the scrambled data to the decoding section.

21. An information reproducing device according to claim 20, wherein a scramble flag for indicating whether or not data recorded in the data recording area is scrambled is further recorded in the information recording medium,

the information reproducing device further comprising a control circuit for controlling whether or not the authentication circuit is to be activated depending on the scramble flag.

22. An information reproducing device according to claim 20, wherein authentication by the authentication circuit is performed by using a predetermined function.

23. An information reproducing device according to claim 20, wherein the information recording medium includes a lead-in area not accessible by devices other than a disk reproducing device and a data recording area,

the key information includes first key information recorded in the lead-in area and second key information recorded in the data recording area, and

the lead-in area includes mutual authentication information for use by the authentication circuit.

24. An information reproducing device according to claim 23, wherein the authentication circuit generates bus key information in the case where authentication processing is normally ended, and encrypts the first key information and the second key information using the bus key information.

25. An information reproducing device according to claim 24, wherein the authentication circuit decrypts the encrypted first key information and the encrypted second key information using the bus key information.

26. An information reproducing device according to claim 23, wherein the descramble circuit descrambles the scrambled data based on information obtained by converting the second key information based on the first key information.

27. An information reproducing device according to claim 20, wherein authentication by the authentication circuit is performed by using information changing over time.

28. An information reproduction method for reproducing scrambled data using a reading device for reading scrambled data and key information to be used for descrambling the scrambled data from an information recording medium and a decoding device including a descramble circuit for descrambling the scrambled data, the method comprising the steps of:

performing mutual authentication processing between the reading device and the decoding device;

generating bus key information common to the reading device and the decoding device in the case where the mutual authentication processing is normally ended between the reading device and the decoding device;

encrypting the key information in accordance with the bus key information; and

transmitting the encrypted key information from the reading device to the decoding device.