Information processing device

1. An information processing device, comprising:

a main bus operable to provide communications within the processing device;

a program execution module for carrying out a process according to a program; and

an execution control module connected to the program execution module via a bus, where the bus is different from the main bus, and the execution control module including a storage section which holds a mutual authentication program to be carried out by the execution control module, the execution control module being operable to:

(i) carry out mutual authentication with the program execution module over the bus,

(ii) carry out a process for authentication relative to an object program for execution by the program execution module,

(iii) prevent the program execution module from executing the object program until the object program is successfully authenticated, and

(iv) control the main bus of the device such that communications via the main bus only become possible when the mutual authentication carried out by the mutual authentication program between the execution control module and the program execution module via the bus has succeeded.

2. The information processing device according to claim 1 , wherein:

the object program has been encoded; and

the execution control module is operable to decode the object program when it has been successfully authenticated, and to supply the object program to the program execution module for use in the process.

3. The information processing device according to claim 2 , wherein: the object program is classified into any of a plurality of predetermined types; and

the execution control module is operable to: (i) store a decoding key, each key for one or more of the predetermined types of object program, and (ii) decode the object program using the decoding key corresponding to the type object program.

4. The information processing device according to claim 1 , wherein the execution control module is operable to:

obtain permission/rejection information for each program, the permission/rejection information indicating whether or not execution of a particular version of the program is permitted; and

cause the program execution module to execute the object program when the permission/rejection information indicates that a given program, having a version identical to a version of the object program, is permitted to be executed.

5. A program execution control method, comprising:

providing a computer having a program execution module for carrying out a process according to a program;

providing an execution control module, connected via a bus to the program execution module;

mitigating communication via a main bus of the computer prior to mutual authentication of the execution control module with the program execution module, the main bus being different from the bus;

carrying out the mutual authentication, within the execution control module, of the execution control module with the program execution module via the bus;

carrying out a process for authentication relative to an object program for execution by the program execution module;

controlling the main bus such that communication via the main bus of the computer only becomes possible when the mutual authentication carried out by the mutual authentication program between the execution control module and the program execution module via the bus has succeeded; and

preventing the program execution module from executing the object program until the object program is successfully authenticated.

6. The method of claim 5 , wherein the bus is a secure bus that exclusively connects the execution control module with the program execution module.

7. The method of claim 6 , further comprising, activating the program execution module and the computer only if the mutual authentication is successfully completed.

8. The method of claim 6 , further comprising, suspending activation of the computer having the program execution module if the mutual authentication fails.

9. The information processing device according to claim 1 , wherein the bus is a secure bus connecting only the program execution module and the execution control module, wherein the secure bus is disparate from the main bus interconnecting all components of the information processing device.

10. The information processing device according to claim 1 , wherein the execution control module is operable to control the main bus such that communications via the main bus only become possible by beginning to operate as a bus master of the main bus when the mutual authentication carried out by the mutual authentication program between the execution control module and the program execution module via the bus has succeeded.