Patent Application
20080303631
The disclosed embodiments relate generally to a mass storage device with a locking system, and more particularly to a portable mass storage device with a wireless locking system.
Portable mass storage devices have the advantages of having large memory capacity and small volume to enable easy carrying, and therefore have become popular storage mediums for use with computer systems.
An example of a portable mass storage device is a USB drive. A USB drive typically includes a storage unit, such as a flash memory chip, to store data. The USB drive also includes a USB mass storage controller to control access to the storage unit. The USB drive also includes a USB connector that provides an interface to a host computer. The USB connector can be a male type-A connector that connects the USB drive directly to a port on the host computer.
Data stored on a portable mass storage device, such as, on the storage unit of the USB drive, is vulnerable to unauthorized access.
In one embodiment, methods and systems to lock and unlock a mass storage device, thus preventing unauthorized access to the USB drive, are described.
Embodiments of a mass storage device having a locking mechanism are described. The mass storage device includes a wireless reader to receive identification data from a wireless transponder, and to determine if the identification data matches a pre-stored data. The mass storage device includes a first controller device to enable access to at least a portion of a mass storage unit when the wireless reader determines that the identification data matches the pre-stored data.
In one embodiment, a method of locking a mass storage device is described. The method includes receiving first identification data from a first wireless transponder at a mass storage device and unlocking the mass storage device upon determining that the first identification data matches a first pre-stored data.
Mass storage device controller 130 operates to manage a flow of data between host device 110 and storage unit 120. Mass storage device controller 130 may contain a small microprocessor and a small amount of on-chip ROM and RAM (not shown). Mass storage device 100 communicates with a wireless transponder device 105 using a wireless reader 160 and antenna 170. Although antenna 170 is shown to be separate from wireless reader 160, in one embodiment, it may be a part of wireless reader 160.
According to some embodiments of the invention, in order to gain access to data stored on mass storage device 100, a user brings wireless transponder device 105 in a proximal range of mass storage device 100. A function of wireless transponder device 105 is to receive an excitation signal from wireless reader 160 and modify the excitation signal in some ways indicative of data identifying the particular wireless transponder that did the modification. Wireless transponder device 105 then transmits the modified signal back to wireless reader 160. In one embodiment, in the absence of stimulus from reader 160, wireless transponder device 105 is dormant and does not transmit data of its own volition.
Wireless transponder device 105 includes a transponder circuit 135, a transmitter/receiver antenna 145 and a memory 125. When brought in proximity to mass storage device 100 containing wireless reader 160, transponder circuit 135 is excited. Transponder circuit 135 is powered by power derived from rectification of incoming wireless signals received from wireless reader 160 or can be self powered. Transponder circuit 135 also includes digital control circuitry to control switching of the antenna connection, whether wireless transponder device 105 is sending or receiving, and reading memory 125. Wireless transponder device 105 also has on-board nonvolatile memory 125 for storing data such as a unique serial number identifying the particular wireless transponder device 105. In one embodiment, at manufacturing time, wireless transponder device 105 is programmed with a unique serial number, referred to herein, as an “Identification Number”. Identification Numbers are discussed in greater detail with reference to
In one embodiment, digital control circuitry 135 keeps wireless transponder device 105 locked so that wireless transponder device 105 cannot alter data in memory 125. Digital control circuitry 135 can also keep wireless transponder device 105 locked so that wireless transponder device 105 cannot or read and transmit data from memory 125 until digital control circuitry 135 detects reception of an unlock sequence. Wireless reader 160 unit knows the unlock sequence for unlocking wireless transponder device 105 to for interrogation, and transmits that sequence plus interrogation or other commands to wireless transponder device 105.
In one embodiment, wireless transponder device 105 is a passive tag. In one embodiment, memory 125 of wireless transponder device 105 is fixed and unalterable, such as ROM or even hardwired connections, thus rendering wireless transponder device 105 read-only.
In another embodiment, for higher security, memory 125 is read-writable. For instance, memory 125 is a 128-bit Programmable Read-Only Memory (“PROM”), thus rendering wireless transponder device 105 read-writeable. Accordingly, a passive read-writable tag allows data stored on and emitted by wireless transponder device 105 to be modified or rewritten during uses, thus further enhancing security. In this case, wireless transponder device 105 is read-writeable. In yet another embodiment, for additional security, wireless transponder device 105 contains a crypto processor to handle data/key encryption and decryption.
Wireless reader 160 includes a microcontroller unit (MCU) 150 for controlling reader functionality and programming. A transceiver circuit 165 is associated with MCU 150. Transceiver circuit 165 generates wireless signals to be passed to antenna 170 for communication with wireless transponder device 105. In one embodiment, an error-detection algorithm, such as the CRC (Cyclic Redundancy Check) algorithm, is implemented at MCU 150 to detect error in transmission. Wireless reader 160 receives the Identification Number from wireless transponder device 105. MCU 150 compares the received Identification Number to pre-stored identification data stored in memory 155 and determines if there is a match.
In some embodiments, wireless reader 160 stores Identification Numbers for one or more matching wireless transponder devices 105 in memory 155 of MCU 150. Wireless reader 160 stores Identification Numbers that correspond to pre-stored Identification data stored in MCU 150. In some embodiments, wireless reader 160 stores Identification Numbers that match pre-stored Identification data stored in MCU 150. In one embodiment, wireless reader 160 stores multiple unique Identification Numbers. In this manner, multiple users, each having one or more associated wireless transponder devices 105, can access one or more same or different portions of storage unit 120. Alternatively, or in addition, the pre-stored identification data can be stored in storage unit 120 and or in mass storage device controller 130.
In one embodiment, memory 155 is non-volatile. In one embodiment, memory 155 is EEPROM. Accordingly, once the one or more Identification Numbers have been successfully programmed, EEPROM 155 fuse is burnt. EEPROM 155 thus acts as read-only device to prevent data tampering. EEPROM 155 may include 1 KB in-system programmable Flash.
If there is a match between one or more Identification Numbers stored at MCU 150 and the Identification Number(s) received from wireless transponder device 105, MCU 150 provides mass storage device controller 130 with this information, so that mass storage device controller 130 can enable access to storage unit 120 by host device 110. In one embodiment, mass storage device controller 130 periodically polls MCU 150 for match information.
In one embodiment, MCU 150 provides mass storage device controller 130 with match information by setting one or more bits 185. Accordingly, a single flag bit or multiple bits 185 stored in mass storage device controller 130 can be used to indicate a match between a received Identification Number and pre-stored identification data. By default, flag bit(s) 185 in mass storage device controller 130 can be set to indicate that there is no match. Once wireless transponder device 105 and wireless reader 160 have communicated successfully, MCU 150 clears bit(s) 185 in mass storage device controller 130. In one embodiment, the bit(s) 185 are used to turn on the mass storage device controller 130.
In another embodiment, MCU 150 provides mass storage device controller 130 with match information by powering on a power switch 180. When powered on, power switch 180 powers up mass storage device controller 130. Mass storage device controller 130 then enables access to storage unit 120 by host device 110.
In one embodiment, mass storage device controller 130 enables access to entire storage unit 120 by host device 110. In one embodiment, mass storage device controller 130 enables access to only a portion of storage unit 120 by host device 110. In certain other embodiments, mass storage device controller 130 enables access to most portions of storage unit 120.
In one embodiment, storage unit 120 (or the part that is unlocked) remains unlocked as long as mass storage device 100 is connected to an active host device 110. Once mass storage device 100 is disconnected from active host device 110, storage unit 120 (or the part that is unlocked) becomes locked. In one embodiment, mass storage device controller 130 employs additional mechanisms to protect storage unit 120 from unauthorized access. For instance, a timer may be employed such that storage unit 120 (or the part that is unlocked) remains unlocked for a pre-defined period of time. Another protection mechanism is to limit the type of access to read-only access.
In one embodiment, a printed circuit board (PCB) of the mass storage device 100 of is extended to about half inch in length to accommodate the housing of wireless reader 160 and antenna 170. In another embodiment, a daughter board can be added to the PCB to house these components.
In some embodiments, transceiver 265 provides mass storage device controller 330 with information received from wireless transponder 205. In some embodiments, mass storage device controller 230 periodically polls transceiver 265 for information received from wireless transponder 205.
In some embodiments of the invention, as illustrated in
As shown in
At the time when a user inserts a RFID locking USB drive device 300 into a USB port of host device 310, USB drive device 300 is locked and not accessible to host device 310. Accordingly, no USB drive device icon is shown on a display associated with host device 310. The user then passes RFID tag 305 by USB drive device 300 having RFID reader 360. RFID reader 360 transmits a magnetic field that provides power for RFID tag 305 to operate. RFID tag 305 transmits a stored Identification Number to RFID reader 360. transceiver 365 detects and sends tag Identification Number to MCU 350 (if one exists). MCU 350 processes tag data and checks to verify that tag data matches with identification data stored at USB drive device 300. If there is a match, MCU 350 will allow USB controller 330 to enumerate. If no MCU 350 exists, processing of tag data is performed by USB controller 330.
If there is a match, a USB drive icon will now appear on a display associated with host device 310 for the user to access data stored on Flash memory chip 320. If there is no match, the USB drive icon does not appear on the display associated with host device 310. USB Drive 300 may use one or more bits or a power switch to control access to flash memory chip 320 in the manner described with reference to
As discussed with reference to
In one embodiment, the PCB of the USB drive 300 is extended to about half inch in length to accommodate the housing of RFID reader 360. In another embodiment, a daughter board can be added to the PCB of USB drive 300 to house RFID reader 360.
RFID tag 305 and RFID reader 360 function as a short range transmitter and receiver respectively. In one embodiment, RFID tag 305 has an operating frequency of 125 kHz. In one embodiment, RFID tag 305 draws power from the integrated RFID reader's 360 magnetic field and is thus passive. In one embodiment, RFID tag 305 is a read-only tag and contains 128-bit of one-time-programmable identification, as described with reference to
At block 411, to gain access to the locked storage unit, a user brings a wireless transponder within a proximal range of the mass storage drive device. The wireless transponder transmits an identification number associated with the wireless transponder, which is received by a wireless reader component of the mass storage drive device at block 421.
At block 431, one or more processing units of the mass storage drive device determine if the received identification number matches a pre-stored number. The processing may be performed by a micro-controller unit within the wireless reader or by a drive controller. If there is no match, then the mass storage drive device stays locked at block 461. Otherwise, if there is a match, at least a portion of the locked mass storage drive device is unlocked at block 441. Optionally, at block 433, the micro-controller unit (if one exists) or the drive controller rewrites the identification number stored on the wireless transponder, for enhanced security. Further, optionally, at block 445, the drive controller invokes a software application, for instance to backup data at the host device. The drive stays unlocked unless the drive is disconnected from the host at block 451.
In some embodiments, for further security, a further challenge and response authentication process is used before unlocking, as described in reference to
According to some embodiments, unlocking of the storage unit occurs after a successful challenge and response process 501 illustrated in
According to some embodiments, for enhanced security, public key cryptography is used before unlocking of the storage unit occurs, as illustrated in process 601 of
In practice, and as recognized by those of ordinary skill in the art, items shown separately could be combined and some items could be separated. The foregoing description, for purpose of explanation, has been described with reference to specific embodiments. However, the illustrative discussions above are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated.
