Program creation apparatus

• US 20050049970A1
• Filed: 08/17/2004
• Published: 03/03/2005
• Est. Priority Date: 08/28/2003
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Yamaguchi, Takao, Sato, Yuji, Itoh, Tomoaki
• Granted Patent: US 7,552,092 B2
• Time in Patent Office: Days
• US Class Current: 705/51
• CPC Class Codes: G06F 21/16 Program or content traceability, e.g. by watermarking
• CPC Class Codes: G06F 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures

Abstract

In the present invention, a program is provided with a dummy module into which a watermark can be inserted without any effect on the operation of the program, and an digital signature. It is thereby possible for a distributor to insert a watermark for specifying a user to the dummy module, and to prevent unauthorized leakage of the program by the distributor. Further, by providing the program body with an digital signature, it is possible to prevent tampering of the program by the distributor.

Claims

1. A program creation apparatus that distributes a created program to a user via a distributor, comprising:

a dummy module adder that adds a dummy module to the program, thereby enabling the distributor to insert a user watermark for specifying the user into the dummy module without any effect on the operation of the program;

a signer that adds an digital signature to the program; and

a transmitter that distributes a distributor program with the dummy module and the digital signature added thereto to the distributor.

2. The program creation apparatus according to claim 1, further comprising:

a watermark inserter that inserts a distributor watermark for specifying the distributor to the program.

3. The program creation apparatus according to claim 1, further comprising:

a program divider that divides the program into a plurality of modules.

4. The program creation apparatus according to claim 1, wherein a secret key for the digital signature that is added to the dummy module by the distributor is transmitted to the distributor.

5. The program creation apparatus according to claim 1, wherein a verification program to check the user watermark inserted by the distributor is added to the program and transmitted.

6. The program creation apparatus according to claim 1, wherein the distributor program is divided into a plurality of portions, and distributed to the user via the distributor.

14. A program distribution system comprising:

the program creation apparatus according to claim 1;

a program distribution apparatus having;

a watermark inserter that inserts a user watermark for specifying the user to the dummy module of the distributor program; and

a transmitter that transmits to the user a user program where the user watermark is inserted into the dummy module; and

a program use apparatus having;

a receiver that receives the user program; and

a watermark checker that checks the user watermark in the user program.

7. A program distribution apparatus comprising:

a watermark inserter that inserts a user watermark for specifying a user into a dummy module of a distributor program where the dummy module and an digital signature are added to a program, the dummy module to which the watermark is inserted without any effect on the operation of the program; and

a transmitter that transmits a user program where the user watermark is inserted into the dummy module to the user.

8. The program distribution apparatus according to claim 7, further comprising:

a signer that adds an digital signature to the dummy module.

9. The program distribution apparatus according to claim 8, wherein the digital signature is added to the dummy module using a secret key for the digital signature transmitted from the program creation apparatus.

10. A program use apparatus comprising:

a receiver that receives a user program where a user watermark for specifying a user is inserted into a dummy module of a distributor program where the dummy module and an digital signature are added to a program, the dummy module to which the watermark is inserted without any effect on the operation of the program; and

a watermark checker that checks the user watermark in the user program.

11. The program use apparatus according to claim 10, further comprising:

a combiner that combines the portions divided from the user program; and

an executor that executes the user program combined.

12. The program use apparatus according to claim 10, wherein the watermark checker acquires a verification program to check the user watermark from a terminal on a transmission path.

13. The program use apparatus according to claim 12, wherein the verification program is included in the verification program.

15. A program distribution method for distributing a created program to a user via a distributor, comprising:

adding a dummy module to the program, thereby enabling the distributor to insert a user watermark for specifying the user into the dummy module without any effect on the operation of the program;

adding an digital signature to the program; and

distributing a distributor program with the dummy module and the digital signature added thereto to the distributor.

16. A program distribution method for distributing to a user a distributor program transmitted in the program distribution method according to claim 15, comprising:

inserting a user watermark for specifying the user to the dummy module of the distributor program; and

transmitting a user program where the user watermark is inserted into the dummy module to the user.

17. A program use method, comprising:

receiving a user program transmitted in the program distribution method according to claim 16;

and

checking the distributor watermark in the user program.

18. A program creation method, comprising:

adding a dummy module to a program, thereby enabling a watermark to be inserted into the dummy module without any effect on the operation of the program; and

adding an digital signature to the program.