Abstract: A mobile telephone includes a CPU that obtains and decodes instructions included in an OS, a nonsecure program, a switch device driver, and a secure program, and operates according to the decoding results. A memory includes a controlled area and an uncontrollable area. The OS has only the controlled area as its access space, and includes an instruction for mediating access of the nonsecure program to the controlled area and an instruction for instructing the switch device driver to make a switch to the secure program. The nonsecure program includes an instruction to access the controlled area via the OS. The switch device driver includes an instruction to make a switch from execution of the OS to execution of the secure program in response to an instruction of the OS. The secure program has only the uncontrollable area as its access space, and includes an instruction to access the uncontrollable area.

Abstract: The present invention offers an electronic device that reduces the amount of data for communication required when files pertaining to software are to be updated, as compared to the conventional devices, and performs tamper detection. The present invention is an electronic device having an application file pertaining to an operation of application software and updating the application file via a network. The electronic device (i) stores therein the application file including one or more data pieces, (ii) receives, from an external apparatus via the network, update data and location information indicating a location, within the application file, which is for rewrite with the update data, (iii) rewrites only part of the application file by writing over a data piece present at the indicated location with the update data, to update the application file, and (iv) examines whether the updated application file has been tampered with.

Abstract: The present invention offers an electronic device that reduces the amount of data for communication required when files pertaining to software are to be updated, as compared to the conventional devices, and performs tamper detection. The present invention is an electronic device having an application file pertaining to an operation of application software and updating the application file via a network. The electronic device (i) stores therein the application file including one or more data pieces, (ii) receives, from an external apparatus via the network, update data and location information indicating a location, within the application file, which is for rewrite with the update data, (iii) rewrites only part of the application file by writing over a data piece present at the indicated location with the update data, to update the application file, and (iv) examines whether the updated application file has been tampered with.

Abstract: A mobile telephone 10 includes: a CPU 102 that fetches and decodes instructions included in an OS, a nonsecure program, a switch device driver, and a secure program, and operates according to the decoding results; and a memory 107 including a controlled area and an uncontrollable area. The OS has only the controlled area as its access space, and includes an instruction for mediating access of the nonsecure program to the controlled area and an instruction for instructing the switch device driver to make a switch to the secure program. The nonsecure program includes an instruction to access the controlled area via the OS. The switch device driver includes an instruction to make a switch from execution of the OS to execution of the secure program in response to an instruction of the OS. The secure program has only the uncontrollable area as its access space, and includes an instruction to access the uncontrollable area.

Abstract: A program storage unit 111 stores a plurality of protected programs. The disabled-program list storage unit 117 stores information of disabled protected programs. An execution program selection unit 112 selects one of the protected programs that is not disabled, with reference a disabled-program list. If malicious analysis is detected before the protected program is executed or during the execution of the protected program, a malicious analysis detection unit 116 stops the execution of the protected program, and a disabled-program update unit 118 enters the disabled program into the disabled-program list.