TWI741271B - Data protection method and associated storage device - Google Patents

Abstract

The present invention provides a data protection method and associated storage device. The data protection method includes:(A): during an initial period after the storage device is connected to a host, performing detection upon the storage device, and determining whether the storage device needs to be performed with data protection; (B): when it is determined that the storage device needs to be performed with data protection in Step (A), modifying a predetermined writing destination that the host writes to a storage unit within the storage device, in order to make data from the host be written to another writing destination of the storage unit instead of the predetermined writing destination; or writing the data from the host into an inner memory or an inner register of a control chip or a bridge chip of the storage device, rather than writing the data from the host into the storage unit; and (C): reporting to the host that the writing operation is completed.

Description

Data protection method and related storage device

In summary, the purpose of the present invention is to provide a method that can protect the external storage device within a period of time when the external storage device is mounted on the host computer when the vulnerability still exists or the malicious program has not been cleared. The data will not be arbitrarily deleted, modified or destroyed.

Incidentally, "within a certain period of time" refers to the time when the user mounts the external storage device on the host computer, until the host computer recognizes the external storage device and displays the storage device on the host computer to allow the user The period of time that ends after the access can be started. In addition, the term "mounting" includes inserting the device into the host computer, or unmounting the device from the host computer, and then mounting it. The so-called "after unmounting, then mounting" can include software actions and hardware actions. The software action means that the device is not actually unplugged from the host computer, while the hardware action means that the device is actually unplugged and then plugged back in. Computer host.

Because of its ease of portability and plug-in, external storage devices (such as external hard drives, flash memory devices, etc.) have become extremely popular on the market, and storing photos and work files in external storage devices is currently a common application . Generally speaking, after the device is connected to the host computer, if the user does not perform further operations on the host computer, the data should not be arbitrarily deleted or repaired. Change and destroy. However, relevant actual research shows that the current computer hosts all over the world have the potential risk of data loss from external storage devices. This is due to the impact of system vulnerabilities or malicious programs, which may cause the computer's operating system itself to be affected. The data in the external storage device is copied or deleted, and even if the user just connects the external storage device to the computer host for a period of time, the stored data may suddenly be damaged or disappear. For example, after the user connects the hard disk or flash drive to the USB slot of the computer via the USB cable, a few seconds later, a window "Your device is ready to use" will pop up on the screen. However, when the user It may be too late when you see this message, and the storage device may be overwritten in this short period of time.

Furthermore, the malicious program will perform abnormal singular or plural write operations to the file system in the storage device for a period of time after the external storage device is mounted on the host computer, thereby causing data damage or disappear.

Computer host system vendors usually lack the willingness to solve these potential vulnerabilities, and even if they provide system update files (or system patches) on the website to reduce the damage caused by specific malicious programs, users often do not actively download these update files. , And it is difficult for manufacturers to solve all possible potential risks at once. Manufacturers often recommend users to back up data to the cloud, but this approach is not without its shortcomings, and the use of external storage devices still has its irreplaceable convenience

In view of the above problems, the purpose of the present invention is to provide a method that can protect the external storage device within a period of time when the external storage device is mounted on the host computer when the vulnerability still exists or the malicious program has not been cleared. The data will not be arbitrarily deleted, modified or destroyed. Specifically, the present invention can achieve this above-mentioned purpose by updating the firmware of the external storage device.

An embodiment of the present invention provides a data protection method for providing security protection. The data protection method includes the following steps: (A): During the initial period when a storage device is connected to a host, the storage device is detected and whether the storage device needs to be protected; (B): Step A When determining that the storage device needs data protection, change a predetermined writing position of the host to the storage device so that the data from the host is written to another writing position different from the predetermined writing position; or The data from the host is written to the internal memory or internal register of the control chip or bridge chip of the storage device, but not to the storage unit; and (C): report that the host system write operation has been completed .

An embodiment of the present invention provides a storage device for data processing and security protection. The storage device includes a storage unit and a processor, wherein the processor is used to perform the following steps: (A): in the storage device During the initial period of connecting to the previous host, detect the storage device and determine whether the storage device needs data protection; (B): When step A determines that the storage device needs data protection, change the host to the storage A predetermined writing position of the unit, so that the data from the host is written to another writing position on the storage unit that is different from the predetermined writing position; or the data from the host is written to the storage device The internal memory or internal register of the control chip or the bridge chip is not written to the storage unit; and (C): report the completion of the write operation of the host system.

In summary, the present invention can provide protection to prevent data from being deleted and tampered during the waiting time when the external hard disk is just connected to the computer. In addition, in the process of the computer host system transmitting commands and data to the storage unit, the present invention uses a controller to filter specific commands and data, so the possibility of data being attacked can be greatly reduced, thereby protecting the data in the storage device. Not be destroyed by malicious actions during this time.

100: storage device

110: Controller

120: storage unit

112: processor

112M: memory

112C: Code

114: Control logic

118: Interface Logic

119: Interface Logic II

130: main device

200: method

202~218: Steps

FIG. 1 is a schematic diagram of a storage device according to an embodiment of the invention.

FIG. 2 is a flowchart of a data protection method applied to a storage device according to an embodiment of the invention.

In the specification and subsequent patent applications, certain words are used to refer to specific elements. Those with ordinary knowledge in the field should understand that hardware manufacturers may use different terms to refer to the same components. The scope of this specification and subsequent patent applications does not use differences in names as a way to distinguish elements, but uses differences in functions as a criterion for distinguishing. The "including" mentioned in the entire specification and the subsequent claims is an open term, so it should be interpreted as "including but not limited to". In addition, the term "coupled" herein includes any direct and indirect electrical connection means. Therefore, if it is described that a first device is coupled to a second device, it means that the first device can be directly electrically connected to the second device, or indirectly electrically connected to the second device through other devices or connection means.

In order to prevent malicious programs from modifying and destroying the external storage device during the period when the external storage device is just connected to the host, the present invention proposes a novel method to protect the data from being arbitrarily deleted, modified, and destroy.

Please refer to FIG. 1, which is a schematic diagram of a storage device 100 according to an embodiment of the present invention. The storage device 100 includes a storage unit 120 and a controller 110, and the controller 110 is used to access the storage unit 120. According to this embodiment, the controller 110 includes a processor 112 and a memory 112M, a control logic 114, an interface logic 118, and an interface logic II 119. The memory 112M is used to store a program code 112C, and the processor 112 is used to execute the program code 112C to control access to the storage unit 120. The control logic 114 or the interface logic II 119 is used to control the storage unit 120. Please note that many elements in Figure 1 are for illustrative purposes only, and are not intended to limit the scope of the present invention. As long as the relevant functions can be substantially maintained, some elements can be replaced or omitted.

In one embodiment, the storage device 100 may be a portable memory device (for example, a memory module that conforms to SD/MMC, CF, MS, and XD standards), and the host such as the main device 130 is a device that can be connected to the memory device Electronic devices, such as mobile phones, laptops, desktop computers... etc. In another embodiment, the storage device 100 may be a solid state drive or an embedded storage conforming to Universal Flash Storage (UFS) or Embedded Multi Media Card (EMMC) specifications. The device may be installed in an electronic device, such as a mobile phone, a notebook computer, or a desktop computer. In this case, the main device 130 may be a processor of the electronic device.

Furthermore, the storage device 100 can be implemented as a hard disk external box, such as a 2.5-inch or 3.5-inch hard disk external box. When the storage device 100 is a 2.5-inch hard disk external box, it can be powered by the main device 130; when the storage device 100 is a 3.5-inch hard disk external box, it can be powered by an external power supply. The storage device 100 includes a controller 110 and a storage unit 120. The controller 110 includes: an interface logic 118 for transmitting with the host device 130; a processor 112 for performing various related operations; and a control logic 114 or The interface logic II 119 is used to communicate with the storage unit 120.

Please refer to FIG. 2, which is a flowchart of a data protection method 200 applied to a storage device according to an embodiment of the present invention. Please note that if substantially the same results can be obtained, these steps do not necessarily have to be executed in the order of execution shown in Figure 2, and the insertion between these steps is not excluded. Possibility of other steps. The method shown in Figure 2 can be used by the storage device 100 shown in Figure 1, and can be briefly summarized as follows: Step 202: First, mount an external storage device (such as the storage device 100) to the host, for example, through The USB cable, USB slot, etc. are designed, but the present invention does not limit the type of external device to be connected to the host through the USB method. In addition, the host can have a built-in card reader (or an external card reader can also be) for inserting memory cards.

Step 204: The controller reads back the file system on the storage unit (such as the storage unit 120), and collects relevant information in the file system.

Step 205: Determine whether the file system exists?

Step 206: When it is determined that there is no file system in the storage unit or the file system has been damaged, the controller does not start (close) the data protection operation (because there is no need to protect the data in this case), and the flow skips to step 218.

Step 207: When it is determined that there is a file system in the storage unit, the controller initiates a data protection operation during the initialization process of the host identifying the external storage device.

Step 208: When the data protection operation has been started, determine the type of instruction received by the controller. When the controller receives at least one specific instruction, the process proceeds to step 210; when the controller receives a write instruction, the process enters Step 212.

Step 210: Turn off the data protection operation, and then skip to step 214.

Step 212: Rewrite the write location of the write command (for example, rewrite to another write location different from the predetermined write location; or rewrite to the internal memory or internal register of the control chip or bridge chip of the storage device , Do not write to the storage unit), or discard the write command.

Step 214: Report that the write command has been successfully written to the host, so that the host determines that the write operation (that is, the tampering operation of the malicious program) has been completed.

Step 216: Determine whether the predetermined time has elapsed (that is, the period when the external device is just plugged into the host time). If yes, go to step 218; if not, go back to step 205, and repeat the process until the data protection operation is closed (for example, from step 208 to step 210) or the process has reached a predetermined time.

Step 218: Once the data protection operation is closed, it will not be activated again. (Until the external storage device is "mounted" to the host again, it will be judged again whether it is necessary to start the data protection operation).

When there is a file system in the storage unit, the controller can use the following methods during the period when the host recognizes the initialization process of the external storage device (that is, during the period when the data is vulnerable to attack) Start data protection operation:

I. Whether to receive some order of order or some combination of order.

II. Whether a certain special instruction is received, or a certain special instruction is received regularly (for example, a certain special instruction is received every few seconds).

III. Whether to receive one or more write commands to write one or more locations (such as logical block address (Logical Block Address, LBA), for example, when the write location points to the file system sector or Cluster When the position is within the range, the data protection operation is started.

IV. Whether to receive one or more read commands to read a certain position (such as LBA), for example, when the read command reads the last LBA on the storage unit, the data protection operation is started .

V. Unconditionally start directly.

When the data protection operation is activated, it will decide whether to turn off the data protection operation according to whether the controller receives a specific command. That is to say, certain types of commands can be directly judged as not being a malicious program attack, so subsequent protection can be omitted action. For example, a specific command may include (but is not limited to) the following commands:

I. Data synchronization commands (such as the SYNCHRONIZE CACHE command of the SCSI command).

II. A certain order of instructions or a combination of certain instructions.

In step 212, when the data protection operation is started and the controller receives the "write command", it selects one of the following two command processing methods:

I. Rewrite the writing position of the command and import the writing position into the free space that does not actually exist in the file system (the file system information collected in step 204 can be used to determine which is the free space).

II. Import the written data carried by the command into a specific storage space inside the controller, and then ignore or discard it. The specific storage space refers to internal memory or internal registers, but not limited to these two Storage components. The specific storage space can also be understood as a garbage collection area, and the garbage (that is, these malicious programs, writing instructions) can be ignored or cleared when the garbage reaches a certain amount.

The above two methods can protect the existing data from being damaged. In other words, because malicious programs and write commands have been imported into a non-existent location or an independent space that has no effect on the stored data, it can completely prevent the stored data from being damaged. To modify or delete.

After the host is reported in step 214 that the write command has been successfully written, the purpose of "spoofing" the host is achieved, so that the host determines that the write operation (that is, the tampering operation of the malicious program) has been completed, thus achieving the purpose of data protection.

Step 216 is to continuously determine whether there is a need to start the data protection operation for a predetermined time (that is, the time when the external device is just plugged into the host), until the predetermined time is over. Once the predetermined time is over, the data protection operation will not be activated after it is closed, because the storage device has been There is no longer a risk of tampering, and the process shown in Figure 2 will not be executed again until the external storage device is removed from the host and the next time the connection is made.

In summary, the present invention can provide protection to prevent data from being deleted and tampered during the waiting time when the external hard disk is just connected to the computer. In addition, in the process of the host transmitting commands and data to the storage unit, the present invention uses the controller to filter specific commands and data, so the possibility of data being attacked can be greatly reduced, thereby protecting the data in the storage device. Not be destroyed by malicious actions within a period of time. The foregoing descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made in accordance with the scope of the patent application of the present invention shall fall within the scope of the present invention.

200: method

202~218: Steps

Claims (5)

A data protection method for providing security protection includes the following steps: (A): During the initial period when a storage device is connected to a host, a controller of the storage device is used to detect the storage device and determine Whether the storage device needs to perform data protection operations, where the initial period is the time from when the storage device is mounted on the host to when the host recognizes the storage device; (B): when step A determines that the storage device needs data protection During operation, use the controller to change a predetermined writing position of the host to a storage unit of the storage device, so that data from the host is written to another writing position different from the predetermined writing position; or Write the data from the host to the internal memory or internal register of the control chip or bridge chip of the storage device without writing to the storage unit; and (C): Use the controller to report the host write The incoming instruction has been completed. The data protection method according to claim 1, wherein the step of determining whether a data protection operation needs to be performed includes: using the controller to read back a file system on a storage unit in the storage device, and collect the The relevant information in the file system is used to determine whether the file system exists, and when the file system is detected in the storage unit, the controller initiates the data protection operation. The data protection method according to claim 2, wherein in the initial time period, before the data protection operation is closed, steps B to C are repeatedly performed. The data protection method according to claim 2, wherein, once the data protection operation is closed After that, it will not start until the storage device is connected to the host next time. A storage device for data processing and security protection. The storage device includes: a storage unit; and a controller for performing the following steps: (A): in the initial period when the storage device is connected to a host, Detect the storage device and determine whether the storage device needs to perform data protection operations, wherein the initial period is the time from when the storage device is mounted on the host to when the host recognizes the storage device; (B): when Step A: When it is determined that the storage device needs to perform a data protection operation, change a predetermined writing position of the host to the storage unit so that the data from the host is written to the storage unit other than the predetermined writing position. A write location; or write data from the host to or write data from the host to the internal memory or internal register of the control chip or bridge chip, but not to the storage unit; and (C): Report that the host's write operation has been completed.

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