Data authentication system

• US 7,373,506 B2
• Filed: 01/19/2001
• Issued: 05/13/2008
• Est. Priority Date: 01/21/2000
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Asano, Tomoyuki, Ishibashi, Yoshihito, Akishita, Toru, Shirai, Taizo
• Primary Examiner(s): Revak; Christopher
• Assistant Examiner(s): Chai; Longbit
• Application Number:
  US09/937,120
• Publication Number:
  US 20020169971A1
• Time in Patent Office: 2,671 Days
• Field of Search: 713/187, 713/193, 380/200, 380/201, 726/26
• US Class Current: 713/168
• CPC Class Codes: 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]
• CPC Class Codes: G06F 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures
• 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 20/00123 the record carrier being identified by recognising some of its unique characteristics, e.g. a unique defect pattern serving as a physical signature of the record carrier
• CPC Class Codes: G11B 20/00173 wherein the origin of the content is checked, e.g. determining whether the content has originally been retrieved from a legal disc copy or another trusted source
• CPC Class Codes: G11B 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00224 wherein the key is obtained from a remote server
• CPC Class Codes: G11B 20/00246 wherein the key is obtained from a local device, e.g. device key initially stored by the player or by the recorder
• CPC Class Codes: G11B 20/00492 wherein content or user data is encrypted
• 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 20/00536 wherein encrypted content data is subjected to a further, iterated encryption, e.g. interwoven encryption
• 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 20/00739 wherein the usage restriction is associated with a specific geographical region
• CPC Class Codes: G11B 20/00753 wherein the usage restriction limits the number of copies that can be made, e.g. CGMS, SCMS, or CCI flags
• CPC Class Codes: G11B 20/00775 wherein said copy control information is encoded in an encryption mode indicator [EMI]
• CPC Class Codes: G11B 2020/00057 MPEG-1 or MPEG-2 audio layer III [MP3]
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 9/0625 with splitting of the data block into left and right halves, e.g. Feistel based algorithms, DES, FEAL, IDEA or KASUMI
• CPC Class Codes: H04L 9/0637 Modes of operation, e.g. cipher block chaining [CBC], electronic codebook [ECB] or Galois/counter mode [GCM]
• CPC Class Codes: H04L 9/0643 Hash functions, e.g. MD5, SHA, HMAC or f9 MAC
• CPC Class Codes: H04L 9/0897 : involving additional devices, e.g. trusted platform module [TPM], smartcard or USB
• CPC Class Codes: H04L 9/14 : using a plurality of keys or algorithms
• CPC Class Codes: H04L 9/3242 : involving keyed hash functions, e.g. message authentication codes [MACs], CBC-MAC or HMAC
• CPC Class Codes: H04L 9/3247 : involving digital signatures
• CPC Class Codes: H04L 9/3273 : for mutual authentication network architectures or network communication protocols for achieving mutual authentication in a packet data network H04L63/0869

Abstract

A data processing system, apparatus and method are provided to verify and validate data. Cryptographic processes employ keys to encrypt the data, check the data and prevent tampering with the data. The data may include header information such as compressed contents or an expansion processing program used to process the data.

Claims

1. A data processing apparatus for processing content data provided by a recording or communication medium, said apparatus comprising:

a cryptography process section for executing a cryptography process on said content data; and

a control section for executing control for said cryptography process section, wherein said cryptography process section is configured to;

split a first portion of header data of the content data having data on usage policy into a plurality of first messages, said header data including a first stored check value therein,

generate a first integrity check value or values from a first key stored in said cryptography process section to verify integrity of the header data by using said plurality of first messages,

collate said first integrity check value or values to verify said first portion of the header data including the usage policy by comparing said first integrity check value or values to said first stored check value,

split a second portion of the header data of the content data having a content key into a plurality of second messages, said header data including a second stored check value therein,

generate a second integrity check value or values from a second key stored in said cryptography process section to verify integrity of the header data by using said plurality of second messages, wherein said second integrity check value or values is generated by applying the second key to a block information table key, the content key and a block information table,

collate said second integrity check value or values to verify said second portion of the header data including said block information table by comparing said second integrity check value or values to said second stored check value,

generate an intermediate integrity check value based on said first integrity check value or values and said second integrity check value or values, and

use said intermediate integrity check value to verify said content data corresponding to said first and second integrity check values.

2. The data processing apparatus according to claim 1, wherein:

said cryptography process is a DES cryptography process, and

said cryptography process section is configured to execute said DES cryptography process.

3. The data processing apparatus according to claim 1, wherein:

said first integrity check value or values and said second integrity check value or values are message authentication codes generated in a DES-CBC mode using said message and said information to be checked;

said intermediate integrity check value is a message authentication code generated in said DES-CBC mode using said first integrity check value or values and said second integrity check value or values to be checked, and

said cryptography process section is configured to execute said cryptography process in said DES-CBS mode.

4. The data processing apparatus according to claim 3, wherein Triple DES is applied in part of a message string to be processed in said DES-CBC mode.

5. The data processing apparatus according to claim 1, further comprising:

a signature key wherein;

said cryptography process section is configured to apply a value generated from said intermediate integrity check value by means of said signature key as a collation value for data verification.

6. The data processing apparatus according to claim 5, wherein:

said signature key includes a plurality of different signature keys; and

said cryptography process section is configured to apply one of said plurality of different signature keys, which is selected depending on a localization of said content data, to said cryptography process for said intermediate integrity check value to obtain said collation value for data verification.

7. The data processing apparatus according to claim 6, further comprising:

a common signature key common to all entities of a system for executing a data verifying process; and

an apparatus-specific signature key specific to each apparatus that executes said data verifying process.

8. The data processing apparatus according to claim 1, further comprising a recording device for storing data validated by said cryptography process section.

9. The data processing apparatus according to claim 8, wherein:

said control section suspends storing of said data in said recording device if a process of collating said first integrity check value or values and said second integrity check value or values is not established in said cryptography process executed by said cryptography process section.

10. The data processing apparatus according to claim 1, further comprising a reproduction process section for reproducing data validated by said cryptography process section.

11. The data processing apparatus according to claim 10, wherein:

said control section suspends reproducing of said data in said reproduction process section if a process of collating said first integrity check value or values and said second integrity check value or values is not established in said cryptography process executed by said cryptography process section.

12. The data processing apparatus according to claim 10, further comprising:

control means for collating only header section integrity check values in said data during said cryptography process executed by said cryptography process section to collate said first integrity check value or values and said second integrity check value or values; and

transmitting to said reproduction process section said data for which collation of said header section integrity check values has been established.

13. The data processing apparatus according to claim 1, wherein the plurality of messages provide multiple input data for a staged encryption.

14. A data processing method for processing content data provided by a recording or communication medium, said method comprising:

splitting a first portion of header data of the content data having data on usage policy into a plurality of first messages, said header data including a first stored check value therein;

generating first integrity check value or values from a first key to verify integrity of the header data by using said plurality of first messages;

collating said first integrity check value or values to verify said first portion of the header data including the usage policy by comparing said first integrity check value or values to said first stored check value;

if said first portion of the header data is verified, splitting a second portion of the header data of the content data having a content key into a plurality of second messages, said header data including a second stored check value therein;

generating second integrity check value or values from a second key to verify integrity of the header data by using said plurality of second messages, wherein said second integrity check value or values is generated by applying the second key to a block information table key, the content key and a block information table;

collating said second integrity check value or values to verify said second portion of the header data including said block information table by comparing said second integrity check value or values to said second stored check value;

if said second portion of the header data is verified, generating an intermediate integrity check value based on said first integrity check value or values and said second integrity check value or values; and

verifying said content data corresponding to said first and second integrity check values using said intermediate integrity check value.

15. The data processing method according to claim 14, wherein said cryptography process is a DES cryptography process.

16. The data processing method according to claim 14, wherein:

said first integrity check value or values and said second integrity check value or values include message authentication codes generated in a DES-CBC mode using said message and said information; and

said intermediate integrity check value is a message authentication code generated in said DES-CBC mode using said first integrity check value or values and said second integrity check value or values.

17. The data processing method according to claim 14, wherein a value generated from said intermediate integrity check value by means of a signature key-applied cryptography process is applied as a collation value for data verification.

18. The data processing method according to claim 17, wherein different signature keys are applied to said cryptography process for said intermediate integrity check value depending on a localization of content data, said different signature keys being applied to obtain said collation value for data verification.

19. The data processing method according to claim 18, further comprising:

selecting and using one of

a common signature key common to all entities of a system for executing a data verifying process; and

an apparatus-specific signature key specific to each apparatus that executes said data verifying process,

said selecting step being based on the localization of said content data.

20. The data processing method according to claim 14, further comprising storing validated data after verifying said content data.

21. The data processing method according to claim 20, further comprising suspending said storing of said validated data if collating of said first integrity check value or values and collating of said second integrity check value or values is not established.

22. The data processing method according to claim 14, further comprising reproducing data after verifying said content data.

23. The data processing method according to claim 22, further comprising:

suspending said reproducing of said data if collating of said first integrity check value or values and collating of said second integrity check value or values is not established.

24. The data processing method according to claim 22, wherein:

said collating of said first integrity check value or values only collates header section integrity check values and transmits said data for which collation of said header section integrity check values has been established to a reproduction process section for reproduction.

25. The data processing method according to claim 14, wherein the plurality of messages provide multiple input data for a staged encryption.

26. A data verifying value imparting method for a data verifying process, said method comprising:

splitting a first portion of header data of data having data on usage policy into a plurality of first messages, said header data including a first stored check value therein;

imparting first integrity check value or values by using said plurality of first messages and a stored first key;

comparing said first integrity check value or values to said first stored check value to verify a usage policy of said header data;

if said usage policy is verified, splitting a second portion of the header data of the data having a content key into a plurality of second messages, said header data including a second stored check value therein;

imparting second integrity check value or values by using said plurality of second messages, wherein said second integrity check value or values is generated by applying a second key to a block information table key, the content key and a block information table;

comparing said second integrity check value or values to said second stored check value to verify said block information table of said header data; and

if said block information table is verified, imparting an intermediate integrity check value to data to be verified, said intermediate integrity check value being used to verify content data corresponding to said first integrity check value or values and said second integrity check value or values.

27. The data verifying value imparting method according to claim 26 wherein said cryptography process is a DES cryptography process.

28. The data verifying value imparting method according to claim 26, wherein:

said first integrity check value or values and said second integrity check value or values are message authentication codes generated in a DES-CBC mode using said message and said information; and

said intermediate integrity check value is said message authentication code generated in said DES-CBC mode using said first integrity check value or values and said second integrity check value or values.

29. The data verifying value imparting method according to claim 26 wherein a value generated from said intermediate integrity check value by means of a signature key-applied cryptography process is applied as a collation value for data verification.

30. The data verifying value imparting method according to claim 29, wherein different signature keys are applied to said cryptography process for said intermediate integrity check value to obtain said collation value, said different signature keys being applied depending on a localization of content data.

31. The data verifying value imparting method according to claim 30, further comprising:

selecting either a common signature key or an apparatus-specific signature key as one of said different signature keys depending upon the localization of said content data, said common signature key being common to all entities of a system for executing said data verifying process, and said apparatus-specific signature key being specific to each apparatus that executes said data verifying process.

32. A recording medium recorded with a computer program for executing a data verifying process having certain actions, said actions comprising:

splitting a first portion of header data of data having data on usage policy into a plurality of first messages, said header data including a first stored check value therein;

executing a collation process using a first integrity check value or values generated by using said plurality of first messages and a stored first key, including comparing said first integrity check value or values to said first stored check value to verify a usage policy of said header data;

if said usage policy is verified, splitting a second portion of the header data of the data having a data key into a plurality of second messages, said header data including a second stored check value therein;

executing a collation process using a second integrity check value or values generated by using the plurality of second messages, including comparing said second integrity check value or values to said second stored check value to verify a block information table of said header data, wherein said second integrity check value or values is generated by applying a second key to a block information table key, the content key and said block information table; and

if said block information table is verified, using an intermediate integrity check value to verify said content data corresponding to said first and second integrity check values, said intermediate integrity check value being based on an integrity check value set obtained by combining at least some of said first and second integrity check values together.