STORAGE DEVICE HAVING AN ANTI-MALWARE PROTECTION

• US 20090307452A1
• Filed: 06/06/2008
• Published: 12/10/2009
• Est. Priority Date: 06/06/2008
• Status: Active Grant

• Current Assignee: Western Digital Israel Limited (Western Digital Corporation)
• Original Assignee: SanDisk IL Ltd. (Western Digital Corporation)
• Inventors: BEN-TSVI, YAAKOV, HAHN, JUDAH GAMLIEL
• Granted Patent: US 8,484,736 B2
• Time in Patent Office: Days
• US Class Current: 711/164
• 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 21/78 to assure secure storage of data address-based protection against unauthorised use of memory G06F12/14; record carriers for use with machines and with at least a part designed to carry digital markings G06K19/00

Abstract

A storage device is protected, when interfaced with a host device, by operating a security processor of the storage device in a “security” mode in which the security processor filters commands that are received from the host device and are targeted to the storage controller, and upon determining by the security processor that the “security” mode is no longer required, by operating the security processor in a “safe” mode in which the security processor (i) does not filter commands it receives from the host device and (ii) forwards to a storage controller of the storage device such unfiltered commands.

Claims

1. A method of protecting a storage device when interfacing with a host device, the method comprising:

operatively interfacing a storage device with a host device, the storage device including a storage area for storing data, a storage controller for managing the storage area, and a security processor;

upon interfacing the storage device with the host device, operating the security processor in a “

security”

mode in which the security processor filters commands that are received from the host device and are targeted to the storage controller; and

upon determining by the security processor that the “

security”

mode is no longer required, operating the security processor in a “

safe”

mode in which the security processor (i) does not filter commands it receives from the host device and (ii) forwards to the storage controller such unfiltered commands.

2. The method according to claim 1, wherein the storage device is a removable storage device or a fixed storage device

3. The method according to claim 1, wherein the storage device contains flash memory.

4. The method according to claim 1, wherein operating the security processor in the “

security”

mode includes;

i) receiving, by the security processor, a command from the host device;

ii) storing in the storage area, by the security processor, the received command, information pertaining to the received command, or both; and

iii) determining, by the security processor, whether the received command is alertable and, if the received command is alertable, logging, by the security processor, the received command in a command alert log.

5. The method according to claim 4, wherein if the received command is determined to be alertable, blocking it, by the security processor, from reaching the storage controller, or ignoring it, and if the received command is non-alertable, passing, by the security processor, the received command to the storage controller.

6. The method according to claim 4, further comprising, responsive to transitioning the security processor from the “

security”

mode to the “

safe”

mode, allowing, by the security processor, the host device to access the command alert log.

7. The method according to claim 4, wherein determination by the security processor whether the received command is alertable is contingent on a previously received command or on a sequence of previously received commands.

8. The method according to claim 7, wherein the sequence of commands includes alretable commands interspersed within other commands.

9. The method according to claim 4, wherein determination by the security processor whether the received command is alertable is contingent on security rules.

10. The method according to claim 1, wherein transition from the security mode to the safe mode is triggered by one of (1) a message received from the host device, (2) a message received over a secure session that is established between the storage device and the host device, and (3) a signal received at the security processor from the host during mutual authentication between the storage device and the host device.

11. The method according to claim 10, wherein the secure session is established using a key-exchange mechanism.