Computer System, Information Processing Apparatus, and Security Protection Method

• US 20120054745A1
• Filed: 05/27/2011
• Published: 03/01/2012
• Est. Priority Date: 08/26/2010
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Digital Solutions Corporation (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Yamashita, Takumi
• Granted Patent: US 8,510,736 B2
• Time in Patent Office: Days
• US Class Current: 718/1
• CPC Class Codes: G06F 21/6209 to a single file or object, e.g. in a secure envelope, encrypted and accessed using a key, or with access control rules appended to the object itself

Abstract

According to one embodiment, a computer system includes a server and a client computer. The client computer is connected to the server via a network. The server includes a takeout management module configured to issue a permit to the client computer when a takeout request is received from the client computer. The permit permits the client computer to store data. The takeout request requests using of data acquired via the network under a condition of being disconnected from the network. The client computer includes a disk device, a takeout request transmitter and a security protector. The takeout request transmitter is configured to transmit the takeout request to the server. The security protector is configured to enable the disk device to store data when the permit is received from the server.

Claims

1. A computer system comprising:

a server; and

a client computer connected to the server via a network, wherein;

the server comprises a takeout management module configured to issue a permit to the client computer when a takeout request is received from the client computer, the permit permitting the client computer to store data, the takeout request requesting using of data acquired via the network under a condition of being disconnected from the network, and

the client computer comprises;

a disk device;

a takeout request transmitter configured to transmit the takeout request to the server, and

a security protector configured to enable the disk device to store data when the permit is received from the server.

2. The system of claim 1, wherein:

the client computer comprises;

a first virtual machine environment where a first operating system (OS) operates, the first OS accepting a user operation and controlling a user-used application program;

a second virtual machine environment where a second OS operates, the second OS managing the first OS; and

a virtual machine monitor environment configured to execute virtualization processing for causing the first OS and the second OS to recognize various devices comprising the disk device arbitrarily,

the first OS comprises a front-end driver configured to issue an operation command for controlling a predetermined device with a storage,

the second OS comprises;

a back-end driver configured to receive the operation command issued by the front-end driver, and

a device driver configured to issue the operation command received by the back-end driver to the disk device, and

the security protector is provided in the second OS, and is configured to;

create a virtual disk image file on the disk device,

instruct the virtual machine monitor environment to cause the first OS to recognize the created virtual disk image file on the disk device as the predetermined device, and

instruct the virtual machine monitor environment to connect a virtual bus for communication between the front-end driver of the first OS and the back-end driver of the second OS so that writing data under the control of the first OS is executable, the communication comprising transmitting and receiving of the operation command about the predetermined device.

3. The system of claim 2, wherein the back-end driver comprises a converter configured to convert the operation command issued by the front-end driver for the predetermined device into an operation command for the disk device in order to access the virtual disk image file.

4. The system of claim 2, wherein:

the permit comprises time limit data indicating a time limit allowing the client computer to store data, and

the security protector is configured to instruct the virtual machine monitor environment to disconnect the virtual bus in order to prevent data from being written and read under the control of the first OS, when the time limit indicated by the time limit data in the permit elapses after the permit is received from the server.

5. The system of claim 4, wherein the security protector is configured to delete the virtual disk image file on the disk device when the security protector disconnects the virtual bus.

6. The system of claim 2, wherein the security protector is configured to instruct the virtual machine monitor environment to disconnect the virtual bus in order to prevent data from being written and read under the control of the first OS when the client computer is connected to the network again.

7. The system of claim 6, wherein the security protector is configured to delete the virtual disk image file on the disk device when the security protector disconnects the virtual bus.

8. The system of claim 2, further comprising a second server connected to the network,

wherein the security protector comprises a data management module configured to save data stored in the virtual disk image file on the disk device in the second server when the client computer is connected to the network again.

9. The system of claim 8, wherein the security protector is configured to delete the virtual disk image file on the disk device after the security protector saved the data stored in the virtual disk image file on the disk device to the second server.

10. The system of claim 2, wherein the security protector is configured to instruct the virtual machine monitor environment to cause the first OS to recognize the virtual disk image file as the predetermined device without newly creating the virtual disk image file, when the virtual disk image file already exists on the disk device.

11. An information processing apparatus connected to a server via a network, comprising:

a disk device;

a takeout request transmitter configured to transmit a takeout request to the server, the takeout request requesting using of data acquired via the network under a condition of being disconnected from the network; and

a security protector configured to enable the disk device to store data when a permit is received from the server, the permit permitting the information processing apparatus to store data.

12. The apparatus of claim 11, further comprising:

a first virtual machine environment where a first OS operates, the first OS accepting a user operation and controlling a user-used application program;

a second virtual machine environment where a second OS operates, the second OS managing the first OS; and

a virtual machine monitor environment configured to execute virtualization processing for causing the first OS and the second OS to recognize various devices comprising the disk device arbitrarily, wherein;

the first OS comprises a front-end driver configured to issue an operation command for controlling a predetermined device with a storage,

the second OS comprises;

a back-end driver configured to receive the operation command issued by the front-end driver, and

a device driver configured to issue the operation command received by the back-end driver to the disk device, and

the security protector is provided in the second OS, and is configured to;

create a virtual disk image file on the disk device,

instruct the virtual machine monitor environment to cause the first OS to recognize the created virtual disk image file on the disk device as the predetermined device, and

instruct the virtual machine monitor environment to connect a virtual bus for communication between the front-end driver of the first OS and the back-end driver of the second OS so that writing data under the control of the first OS is executable, the communication comprising transmitting and receiving of the operation command about the predetermined device.

13. The apparatus of claim 12, wherein the back-end driver comprises a converter configured to convert the operation command issued by the front-end driver for the predetermined device into an operation command for the disk device in order to access the virtual disk image file.

14. The apparatus of claim 12, wherein:

the permit comprises time limit data indicating a time limit allowing the client computer to store data, and

the security protector is configured to instruct the virtual machine monitor environment to disconnect the virtual bus in order to prevent data from being written and read under the control of the first OS, when the time limit indicated by the time limit data in the permit elapses after the permit is received from the server.

15. The apparatus of claim 14, wherein the security protector is configured to delete the virtual disk image file on the disk device when the security protector disconnects the virtual bus.

16. The apparatus of claim 12, wherein the security protector is configured to instruct the virtual machine monitor environment to disconnect the virtual bus in order to prevent data from being written and read under the control of the first OS when the client computer is connected to the network again.

17. The apparatus of claim 16, wherein the security protector is configured to delete the virtual disk image file on the disk device when the security protector disconnects the virtual bus.

18. The apparatus of claim 12, wherein the security protector is configured to instruct the virtual machine monitor environment to cause the first OS to recognize the virtual disk image file as the predetermined device without newly creating the virtual disk image file, when the virtual disk image file already exists on the disk device.

19. A security protection method of an information processing apparatus which comprises a disk device and is connected to a server via a network, the method comprising:

transmitting a takeout request to the server, the takeout request requesting using of data acquired via the network under a condition of being disconnected from the network; and

enabling the disk device to store data when a permit is received from the server, the permit permitting the information processing apparatus to store data.