CN101739360B - How to protect memory data - Google Patents

Abstract

A method for protecting internal memory data includes storing damaged block information, fetching out damaged block address detected out by internal memory when internal memory is scanned and tested as internal memory mark, utilizing specific algorithm to calculate out identification code from damaged block address to let internal memory check said identification code first and confirm whether internal memory pointed by internal memory mark is damaged block or not for preventing unauthorized copied data from being read out for using it at will.

Description

How to protect memory data

technical field

The invention relates to a method for protecting memory data, in particular using the damaged block address of the memory as a mark and an identification code to protect stored data and prevent arbitrary reading.

Background technique

With the rapid development of the information industry, the use of storage devices is becoming more and more popular and the capacity is also increasing. At present, various storage devices have been used as data storage interfaces, and the protection of data security is becoming more and more important.

Most of the current storage device data protection methods are protected by passwords. For example, the protected file content is locked by a password. Only when the password is correct, the storage device allows the external computer to read the stored data, or the stored data. The data has been encoded by the password, so when an external computer reads it, if it does not obtain the password to decode the file, it will read the encoded data and cannot use it directly. Another commonly used protection method is the protection method of file system characteristics. Using the published file system format, a specific file or identification code is implanted into a specific reserved area to monitor external access operations on memory data and prevent arbitrary copying to protect memory data.

However, the disadvantage of the prior art is that any data in the protected storage device executed by a computer in the form of a software program may still be cracked and fail, and the protection method of the file system characteristic can only protect the data of a single storage device. However, it is still impossible to prevent the pair-to-bake operation performed by the physical address, that is, it is impossible to prevent the one-to-one data copy operation of the two storage devices by using the copy machine to copy the data by the memory address. Taking the flash drive as an example, copying two flash drives by burning can break through the protection method of the file system characteristics, and then obtain a large number of flash drives with the same data.

Therefore, there is a need for a method for protecting memory data, which eliminates the protection method of software and directly utilizes the hardware characteristics of the memory itself, so as to solve the shortcomings of the prior art.

Contents of the invention

The main purpose of the present invention is to provide a method for protecting memory data. From the storage bad block information (Storage Bad Block Info), the address of the bad block detected when the memory is scanned and tested is taken out to be used as a memory block. Mark, that is, the hardware mark of the memory, and use a specific algorithm to calculate the identification code from the address of the damaged block, so that when the outside world reads the memory data, the memory will first check the identification code and the address of the damaged block to prevent unauthorized The copied data is read out and used arbitrarily to achieve the purpose of protecting memory data.

Another object of the present invention is to provide a method for protecting memory data, select a plurality of damaged block addresses of the memory as memory marks, calculate the average value through appropriate functions as identification codes, and store the memory marks and identification codes in In the specific address of the memory, after the data in the memory is copied to another memory, when the user reads the data in another memory, the other memory will first compare whether the identification code stored in the specific location is If the function value calculated by the function and the memory mark is correct, then further confirm whether the memory block specified by the memory mark is a damaged block, if correct, then determine that the data in the memory is authorized data, and proceed Data read operation, and transmit the memory data to the user, otherwise the memory data will be regarded as unauthorized data, thereby preventing the outside world from reading the memory data, so as to protect the memory data from being copied arbitrarily.

Therefore, through the method for protecting memory data provided by the present invention, when the original memory data is copied to another memory in the form of a physical address, the data in the other memory cannot be read and protected, so as to solve the problem of the above-mentioned prior art all the shortcomings.

Description of drawings

FIG. 1 is a flow chart showing the memory data writing operation of the memory data protection method of the present invention.

FIG. 2 is a flowchart showing the memory data reading operation of the memory data protection method of the present invention.

FIG. 3 is a schematic diagram showing protection operations of the memory data protection method of the present invention.

[Description of main component symbols]

10 raw memory

12 memory tag

30 copy memory

32 memory tag

A, B, C, D, E, F, G blocks

Ax, Bx, Cx block address

S110 Read damaged block address

S120 Select multiple damaged block addresses as memory marks

S130 Use a suitable function to bring in the memory tag to calculate the identification code

S140 Store the memory tag and identification code in a specific address of the memory

S150 end write operation

S200 Start the read operation of the protection method of the present invention

S210 read memory mark and identification code

Whether the identification code of S220 is correct

S230 Whether the block specified by the memory mark is a damaged block

S240 executes the read operation of memory data

S250 unauthorized memory data

S260 stops the read operation of memory data

S270 ends the read operation

Φ identification code

Detailed ways

The implementation of the present invention will be described in more detail below in conjunction with the accompanying drawings and component symbols, so that those skilled in the art can implement it after studying this specification.

The memory data protection method of the present invention mainly includes two stages of operations: the memory data writing operation of the first stage and the memory data reading operation of the second stage. The memory data write operation establishes a mechanism in the memory to prevent unauthorized reading of memory data, and the memory data read operation uses the mechanism established in the first stage to identify whether the read memory data is Authorized memory data.

The memory data protection method described above is operated by a memory read-write controller, that is, the memory data write operation and memory data read operation are implemented by the read-write controller. The read-write controller can be a general microprocessor, which executes specific software to realize the memory data protection method, but the read-write controller can also be an application specific integrated circuit (Application Specific IC, ASIC) without software, and directly uses hardware The circuit realizes the memory data writing operation and the memory data reading operation. In addition, independent electrical components can also be combined to form a circuit module capable of implementing memory data writing operations and memory data reading operations. Therefore, the scope of the present invention is not limited to the physical form and internal operation of the controller implementing the memory data protection method.

Referring to FIG. 1 , it is a flow chart of the memory data writing operation of the memory data protection method of the present invention. As shown in FIG. 1 , firstly, in step S100 , the write operation of the protection method of the present invention is started, and step S110 is entered. In step S110, read the damaged block address stored in the damaged block information, and proceed to step S120. In step S120, a plurality (or more) of damaged block addresses are selected as memory tags, and the process proceeds to step S130. In step S130, the specific function is used to bring in the memory tag to calculate the identification code, and the process proceeds to step S140. In step S140, the memory tag and identification code are stored in a specific address of the memory, and the process proceeds to step S150. In step S150, the writing operation is ended.

To store damaged block information is generally to record the addresses of all damaged blocks when the memory is scanned and tested, and store them in a specific address of the memory, so that the memory controller can read the address of the damaged block to avoid damage to the damaged block. block for data access. The specific function in step S130 can be any function, such as adding up the selected damaged block addresses, or taking an average value, or taking a maximum value. However, it should be noted that the protection method of the present invention does not limit the form of a specific function, that is, as long as a value can be obtained as an identification code by bringing in the selected damaged block address, it falls within the scope of the present invention. In addition, the specific address for storing the memory tag and identification code can be selected arbitrarily, as long as it is a non-damaged block.

Referring to FIG. 2 , the flow chart of the memory data reading operation of the memory data protection method of the present invention. As shown in FIG. 2 , firstly in step S200 , after receiving the data reading request from the external device, the memory starts the reading operation of the protection method of the present invention, and then enters step S210 . In step S210, the memory tag and identification code of the specific address of the memory are read, and the process proceeds to step S220. In step S220, it is judged whether the identification code is correct, if correct, proceed to step S230, and if not, proceed to step S250. In step S230, it is judged whether the block designated by the memory mark is a damaged block, if it is a damaged block, proceed to step S240, and if it is not a damaged block, proceed to step S250. In step S240, the memory data is confirmed as authorized data, the read operation of the memory data is executed, and the read memory data is sent out, and the process proceeds to step S270. In step S250, the internal memory data is confirmed as unauthorized internal memory data, and the process proceeds to step S250. In step S260, the operation of reading the memory data is stopped, and the process proceeds to step S250. In step S270, the read operation is ended.

The external device in step S200 can be a personal computer, a notebook computer or a personal digital assistant. The method of judging whether it is a damaged block in step S230 can be realized by writing and reading, that is, first writing a specific value and then reading the value and comparing it, or repeatedly writing and reading different values into the memory address, and compare data at the same time. However, it should be noted that the protection method of the present invention does not limit the method of memory determination in step S230.

Therefore, the present invention checks whether the identification code is correct and checks whether the memory block of the memory mark is a damaged block by step 230 and step 240 respectively, to confirm whether the memory data is authorized data, so as to prevent any copied memory data from being read take out.

To further illustrate the content of the present invention, please refer to FIG. 3 , which is a schematic diagram of the protection operation of the memory data protection method of the present invention. As shown in Figure 3, the original memory 10 has a plurality of damaged blocks, such as blocks A, B, C, D, E, F, G, which are recorded in the stored damaged block information, select blocks A, B, The block address Ax, Bx, Cx of C is used as the memory mark 12 of the original memory 10, and the specific function f is used to generate the identification code Φ, that is, f(Ax, Bx, Cx)=Φ. The specific function f can be the addition of the selected damaged block addresses Ax, Bx, and Cx as mentioned above, or take the average value, or take the maximum value, but the present invention does not limit the form of the specific function.

It should be noted that the present embodiment selects the addresses of the three blocks A, B, and C as memory marks, which is only an exemplary example for convenience of description, and is not intended to limit the scope of the present invention, that is, the method of the present invention is included in all Select any number of damaged blocks in the damaged block and use the address of the damaged block as a memory mark.

The memory mark 12 and the identification code Φ are stored in a specific address of the original memory 10, such as 0x00fd for convenience of explanation, and other addresses of the original memory 10 are available for storing data. Since the original memory 10 has a memory mark 12 and an identification code Φ, the data stored in the original memory 10 is regarded as authorized memory data.

When the data of the original memory 10, including the memory mark 12, the identification code Φ and the memory data, are successfully copied to the copy memory 30, the copy memory 30 has the memory mark 32, the identification code Φ and the memory data, wherein the memory mark 32 and the identification The code Φ is located at a specific address 0x00fd of the copied memory 30 , while the memory data is located at other corresponding memory addresses, that is, the same as the original memory 10 .

Calculate the function value by the memory mark 32 through the specific function, i.e. f(Ax, Bx, Cx), and compare f(Ax, Bx, Cx) with the identification code Φ, if they are not the same, it means that the copy memory 30 The memory data is not authorized memory data, and the memory and its controller prevent external data read operations. If f (Ax, Bx, Cx) is the same as the identification code Φ, then check whether the selected block A, B, C of the copy memory 30 is a damaged block, if it is not a damaged block, it means the memory data of the copy memory 30 The memory data is not authorized, and the memory and its controller prevent external data read operations. If A, B, and C are all damaged blocks, it can be confirmed that the memory data in the duplicate memory 30 is authorized memory data, and the duplicate memory 30 allows external data reading operations and transmits the read data.

It should be noted that, although the copy memory 30 itself has damaged block information stored, it is different from the stored damaged block information of the original memory 10 because the memory is formed on a wafer by a semiconductor process and is limited by the size of the wafer itself. Process variables, so that each memory defect is not the same, that is, have different damaged blocks. Therefore, the memory mark 12 and the memory mark 32 can be regarded as the identification fingerprints of the original memory 10 and the copy memory 30 respectively, that is, the method of the present invention uses the hardware characteristics of the memory as a tool for identifying whether it is authorized memory data.

Therefore, the method of the present invention can confirm whether it is authorized memory data through the hardware characteristics of the memory, thereby preventing unauthorized copying of the memory data from being read or used arbitrarily, so as to protect the memory data.

The above descriptions are only preferred embodiments for explaining the present invention, and are not intended to limit the present invention in any form. Therefore, any modification or change of the present invention made under the spirit of the same invention is still valid. It should be included in the intended protection scope of the present invention.

Claims (7)

1. the guard method of an internal storage data, in order to protect an internal storage data of an internal memory, the guard method of this internal storage data may further comprise the steps:

One internal storage data write operation, with a memory marker of this internal memory and an identification code that is calculated through a specific function by this memory marker, be stored to a particular address of this internal memory, then this internal storage data is stored in this internal memory, wherein this memory marker comprises the bad block address of a plurality of bad blocks of this internal memory; And

One internal storage data read operation, when receiving a data read request of an external device, read this memory marker and this identification code of this internal memory, relatively whether identical through a functional value and this identification code that this specific function calculated by this memory marker, and whether the block of checking this internal memory that this memory marker is specified is bad block, if this functional value is identical with this identification code and the block of this internal memory that this memory marker is specified is a bad block, confirm that then this stored internal storage data of this internal memory is an internal storage data of authorizing, and carry out a data read operation and data streams read is sent to this external device, otherwise stop the data read request of this external device.

2. the guard method of internal storage data according to claim 1 saves as a flash memory in wherein being somebody's turn to do.

3. the guard method of internal storage data according to claim 1, wherein this specific function is a max function, in order to choose the maximal value in this bad block address.

4. the guard method of internal storage data according to claim 1, wherein this particular address is the address of this bad block memory block in addition of this internal memory.

5. the guard method of internal storage data according to claim 1, wherein this external device is a personal computer.

6. the guard method of internal storage data according to claim 1, wherein this external device is a mobile computer.

7. the guard method of internal storage data according to claim 1, wherein this external device is a personal digital assistant.

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