DATA PROVIDING SYSTEM, DATA RECEIVING SYSTEM, COMPUTER-READABLE RECORDING MEDIUM STORING DATA PROVIDING PROGRAM, AND COMPUTER-READABLE RECORDING MEDIUM STORING DATA RECEIVING PROGRAM

• US 20080170696A1
• Filed: 01/10/2008
• Published: 07/17/2008
• Est. Priority Date: 01/16/2007
• Status: Active Grant

• Current Assignee: Kyocera MITA Corporation (Kyocera Corporation)
• Original Assignee: Kyocera MITA Corporation (Kyocera Corporation)
• Inventors: Kawai, Takanao, Yoshimura, Sachiko
• Granted Patent: US 7,995,761 B2
• Time in Patent Office: Days
• US Class Current: 380/277
• 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 21/57 Certifying or maintaining trusted computer platforms, e.g. secure boots or power-downs, version controls, system software checks, secure updates or assessing vulnerabilities
• CPC Class Codes: G06F 2221/2107 File encryption

Abstract

A data providing system is provided which includes: a storage section which stores an encoded file obtained by encoding a data file to be distributed with a predetermined common key and an encoded information file obtained by encoding an information data file including information on the common key with a private key different from the common key; and a file transfer section which transfers the encoded file and the encoded information file from the storage section to external electronic device.

Claims

1. A data providing system, comprising:

a storage section which stores an encoded file obtained by encoding a data file to be distributed with a predetermined common key and an encoded information file obtained by encoding an information data file including information on the common key with a private key different from the common key; and

a file transfer section which transfers the encoded file and the encoded information file from the storage section to external electronic device.

2. The data providing system according to claim 1, wherein:

the storage section further stores an encoded digest obtained by encoding a digest file including a hash value intrinsic to the data file to be distributed with a predetermined private key; and

the file transfer section transfers the encoded digest as well as the encoded file and the encoded information file to the electronic device.

3. The data providing system according to claim 1, wherein the file transfer section transfers at least the encoded file and the encoded information file in such a manner that both are interrelated.

4. A data receiving system, comprising:

an access section which accesses to a storage section storing an encoded file obtained by encoding a data file to be distributed with a predetermined common key and an encoded information file obtained by encoding an information data file including information on the common key with a private key different from the common key; and

a file read-in section which reads in, using the access section, the encoded file and the encoded information file from the storage section.

5. The data receiving system according to claim 4, further comprising:

an information-file generation section which generates the information data file by decoding the encoded information file read in by the file read-in section, using a public key to make a pair of the private key;

a key extraction section which extracts the common key from the information included in the information data file generated by the information-file generation section; and

a file decoding section which decodes the encoded file read in by the file read-in section, using the common key extracted by the key extraction section.

6. The data receiving system according to claim 4, wherein:

the storage section further stores an encoded digest obtained by encoding a digest file including a hash value intrinsic to the data file to be distributed with a predetermined private key;

the file read-in section reads in, using the access section, the encoded digest as well as the encoded file and the encoded information file from the storage section; and

a digest generation section is further provided which generates the digest file by decoding the encoded digest using a public key to make a pair of the private key used for obtaining the encoded digest read in by the file read-in section.

7. The data receiving system according to claim 5, wherein:

the storage section further stores an encoded digest obtained by encoding a digest file including a hash value intrinsic to the data file to be distributed with a predetermined private key; and

the file read-in section reads in, using the access section, the encoded digest as well as the encoded file and the encoded information file from the storage section,

further comprising;

a digest generation section which generates the digest file by decoding the encoded digest using a public key to make a pair of the private key used for obtaining the encoded digest read in by the file read-in section;

a hash-value calculation section which calculates a hash value of the file obtained by decoding the encoded file using the file decoding section; and

an authentication section which authenticates the file obtained by decoding the encoded file, based on a comparison result between the hash value acquired from a digest generated by the digest generation section and the hash value calculated by the hash-value calculation section.

8. The data receiving system according to claim 4, wherein:

the storage section stores a list file including the file name of an authentic program stored in this storage section; and

if the file name of the encoded file and the encoded information file is not stored in the list file stored in the storage section when the file read-in section reads in the encoded file and the encoded information file from the storage section, then the file read-in section stops reading in these encoded file and encoded information file.

9. The data receiving system according to claim 4, wherein the file read-in section reads in, from the storage section, at least the encoded file and the encoded information file in such a manner that both are interrelated.

10. A computer-readable recording medium storing data providing program which allows a computer including a storage section having a predetermined storage area to execute:

a procedure for generating an encoded file obtained by encoding a data file to be distributed with a predetermined common key;

a procedure for generating an encoded information file obtained by encoding an information data file including information on the common key with a private key different from the common key;

a procedure for storing the encoded file and the encoded information file in the storage area; and

a procedure for transferring the encoded file and the encoded information file from the storage section to external electronic device.

11. The computer-readable recording medium storing the data providing program according to claim 10, which allows the computer including the storage section to further execute:

a procedure for storing, in the storage area, an encoded digest obtained by encoding a digest file including a hash value intrinsic to the data file to be distributed with a predetermined private key; and

a procedure for transferring the encoded digest as well as the encoded file and the encoded information file to the electronic device.

12. A computer-readable recording medium storing a data receiving program which allows a computer to execute:

a procedure for giving access to a storage section storing an encoded file obtained by encoding a data file to be distributed with a predetermined common key and an encoded information file obtained by encoding an information data file including information on the common key with a private key different from the common key; and

a file procedure for giving access to the storage section and reading in the encoded file and the encoded information file from the storage section.

13. The computer-readable recording medium storing the data receiving program according to claim 12, which allows the computer to further execute:

a procedure for generating the information data file by decoding the encoded information file transferred from the storage section, using a public key to make a pair of the private key; and

a procedure for extracting the common key from the information included in the information data file so that the encoded file transferred from the storage section is decoded.

14. The computer-readable recording medium storing the data receiving program according to claim 12, which allows the computer to further execute:

a procedure for giving access to the storage section which further stores an encoded digest obtained by encoding a digest file including a hash value intrinsic to the data file to be distributed with a predetermined private key, as well as the encoded file and the encoded information file; and

a procedure for reading in, from the storage section, the encoded digest as well as the encoded file and the encoded information file; and

a procedure for generating the digest file by decoding the encoded digest using a public key to make a pair of the private key used for obtaining the encoded digest.