1. Technical Field
The present invention generally relates to memory cards and accessing methods and accessing systems for the same and, more particularly, to a memory card which is limited to be accessed by a special machine and an accessing method and an accessing system for the same.
2. Description of the Related Art
Nowadays, information is widely spread in the society, and how to conveniently carry the information for use in various different circumstances has become a focus of attention of people. In order to achieve the purpose of conveniently carrying the information, many kinds of related technologies have been widely used. The related technologies are directed to portable computers, universal serial bus (USB) hard disks, and various types of memory cards and so on and rapidly developed to meet people's various different needs.
In the above-mentioned technologies, although a memory card generally has a storage capacity smaller than that of a portable computer and a USB hard disk; it is undoubtedly that the memory card is one type of portable storage media relatively most easy to carry. Furthermore, a ratio of a volume to the storage capacity of the memory card is continuously decreased.
However, with the widespread use of the memory cards, information abuse and security issues are raised. A memory card which has large amounts of data stored therein facilitates the user to carry large amounts of information, but also runs the risk of data leak in case of the memory card is lost. The risk of data leak generally results from the data accesses of most memory cards do not have any limitation, so that once the memory card is lost, the person who picks up the lost memory card may easily acquire the information stored in the memory card through an arbitrary machine.
The present invention is to provide a memory card accessing method that is able to avoid a memory card to be accessed by an arbitrary machine.
The present invention is to further provide a memory card accessing system that is able to make a special memory card only to be accessed by a special machine.
The present invention is to still further provide a memory card that is able to reduce the risk of data leak resulting from the stored data being arbitrarily accessed.
In order to achieve the above-mentioned objects, a memory card accessing method in accordance with an embodiment of the present invention is provided. The memory card accessing method is adapted to a machine using a first operating system. The memory card accessing method firstly checks whether data in the memory card is stored according to a data storage type supporting both the first operating system and a second operating system. When the data in the memory card is confirmed not to be stored according to the data storage type, the machine is prohibited from accessing the data stored in the memory card. In addition, a version value is stored in the memory card, and the version value is a value different from a predetermined version value. When the version value is confirmed to be different from the predetermined version value, the second operating system deems the memory card un-accessible.
In one embodiment, when the machine is permitted to access the data stored in the memory card, the memory card accessing method further performs a logic operation to the data stored in a file allocation table of the memory card so as to obtain a decoded file allocation table via conversion, and then accesses the memory card based on the data in the decoded file allocation table.
A memory card accessing system in accordance with another embodiment of the present invention is provided. The memory card accessing system includes a memory card and a machine. Data in the memory card is stored according to a data storage type supporting a first operating system. The memory card has a first identification code stored therein. The machine uses the first operating system. The machine includes a software storage region for storing software which is for performing data access function to an external memory device, an identification data storage region for storing an identification data associated with the machine, and a processing unit. The processing unit is used for performing the first operating system and the software to acquire the first identification code from the memory card and a second identification code from the identification data and then determining the machine whether accesses the memory card according to whether the first identification code and the second identification code satisfy a first predetermined relationship.
A memory card in accordance with still another embodiment of the present invention is provided. The memory card is adapted to insert into a machine for accessing data stored in the memory card. The data in the memory card is stored according to a data storage type supporting a first operating system. It is characterized in that the memory card has an identification data stored therein. The identification data is read by the machine to compare with a machine identification data stored in the machine, when the memory card is inserted into the machine. The memory card permits to be accessed by the machine, when the identification data and the machine identification data satisfy a predetermined relationship.
In one embodiment, the identification data stored in the memory card includes a version value. When the version value is different from a predetermined version value, the operating system deems the memory card as an un-accessible memory media.
In another one embodiment, the memory card includes a data storage area for storing a file and a file allocation table for storing a storage location of the file in the data storage area. The storage location of the file in the data storage area which is stored in the file allocation table is different from an actual storage location of the file in the data storage area and determined by a special logic operation.
In the various embodiments of the present invention, since the machine and the memory card are provided with special identification data for comparison, the memory card only permits to be accessed by a special machine. Correspondingly, the machine also only accesses some special memory cards. Therefore, due to the memory card is prevented from being accessed by an arbitrary machine, the risk of data leak for the memory card would be greatly reduced.
Other objectives, features and advantages of the present invention will be further understood from the further technological features disclosed by the embodiments of the present invention wherein there are shown and described preferred embodiments of this invention, simply by way of illustration of modes best suited to carry out the invention.
These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which like numbers refer to like parts throughout, and in which:
It is to be understood that other embodiment may be utilized and structural changes may be made without departing from the scope of the present invention. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms “connected,” “coupled,” and “mounted,” and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings.
In the present embodiment, the memory card 10 has a group of identification data stored in the boot area 104. The group of identification data is read out when the memory card 10 is inserted into a machine, to compare with a corresponding machine identification data (which is described below in detail) stored in the machine. Only if the identification data stored in the memory card 10 and the machine identification data stored in the machine are confirmed to satisfy a predetermined relationship (e.g., are identical with each other) after comparison, the memory card 10 permits to be accessed by the machine.
In practical applications, in the memory card 10, the identification data may be an identification code stored in the parameter storage section of the boot area 104, a version value stored in the version storage section of the boot area 104, or even both the identification code and the version value.
It is indicated that the version value in the FAT32 storage type has its specific use, taking a windows operating system as an example, a memory card which is deemed by the windows operating system as being formatted in the FAT32 storage type, a predetermined value of the version value thereof is zero. The windows operating system checks all the values of the parameters stored in the boot area 104, as long as a value of any one of the parameters stored in the boot area 104 is different from the predetermined value of the FAT32 storage type, the windows operating system deems the data storage area 108 being unformatted. For example, the windows operating system checks the version value stored in the boot area 104 of the memory card 10, if the version value stored in the boot area 104 is zero, the windows operating system continues to check the values of the other parameters whether are respective predetermined values of the parameters of the FAT32 storage type after confirming the version value is zero. By way of checking the values of the parameters stored in the boot area 104, the data storage area 108 whether is completely formatted according to a given manner of the FAT32 storage type is acquired. When the version value is not zero, the windows operating system deems the data storage area 108 being unformatted, in this situation, the memory card 10 is taken as an un-accessible memory media by the windows operating system.
Furthermore, by way of setting the identification codes stored in the memory card 10 and the machine, the memory card 10 is limited to be accessed by a special machine. Correspondingly, the machine also is set to only access a special memory card 10. In another aspect, by way of setting the version value, an actual formatted memory card 10 may be deemed as unformatted by the operating system and thus an unauthorized machine is prohibited from accessing the memory card 10.
Furthermore, if various types of identification data between the machine and the memory card 10 are checked and confirmed to be right, the machine is permitted to perform data access to the memory card 10. In this circumstance, there is another approach to effectively protect the data stored in the memory card 10. In particular, as described above, the file allocation table 106 is used for storing the storage locations of the files and documents in the data storage area 108, therefore in order to access the data stored in the memory card 10, the machine need rely on the data stored in the file allocation table 106. Based upon this point, in one embodiment of the present invention, before accessing the data stored in the memory card 10, it is needed to firstly perform a logic calculation (e.g., exclusive or (XOR) logic operation) to the file allocation table 106 so as to obtain a decoded file allocation table via conversion. Actual storage locations of files and documents are determined by the data in the decoded file allocation table. Accordingly, even if an unauthorized machine accesses the memory card 10, it still acquires the actual content of the data stored in the memory card 10 due to the accessed data are messy at the condition of without the decoded file allocation table.
In the present embodiment, the machine 20 uses another operating system (e.g., a Linux operating system). Furthermore, the identification data storage region 202 is used for storing an identification data associated with the machine 20; the software storage area 204 is used for storing software for performing data access to an external memory device (e.g., the memory card 22) and/or the operating system itself. The processing unit 200 is used for loading the operating system and the above-mentioned software into the memory 206 and implementing the operating system and the software in the memory 206 to acquire the identification code (hereinafter also referred to as first identification code) as described in the foregoing embodiment from the memory card 22 and another identification code (hereinafter also referred to as second identification code) from the identification data stored in the identification data storage area 202. Thereafter, the processing unit 200 determines the machine 20 whether be able to access the memory card 22 based on whether the first and the second identification codes satisfy a predetermined relationship.
The identification data storage region 202 also stores a machine version value besides the identification code as described in the foregoing embodiment. The machine version value is another basis except the identification code for determining whether the machine 20 is permitted to access the memory card 22.
In the machine 20, since the identification data generally does not need a large storage space, in order to facilitate the data erase and program, an electrically erasable programmable read only memory (EEPROM) is used as a memory for the identification data storage region 202. In contrast, because the software and the operating system generally need a large storage space and have a little chance to be modified, an NOR flash memory is considered as a memory for the software storage region 204.
In order to describe a memory card accessing method in detail, a flow chart of the memory card accessing method in accordance with one embodiment is illustrated in
In the present embodiment, if the result in step S306 is YES, the machine acquires the version value as mentioned in both the two foregoing embodiments from the memory card (step S308). The version value then is checked to determine whether it meets a rule (step S310). It is indicated that there are various approaches for confirming the version value whether meets the rule or not. For one example, setting a predetermined accessible version value in the software installed in the machine and then checking a version value obtained from the memory card and the predetermined accessible version value whether satisfy a predetermined relationship. For another example, storing an accessible version value in the identification data storage region 202 of the machine 20 of
In the present embodiment, the proper access operations include the steps S312 and S314. Firstly, before accessing the content of file stored in the memory card, a file allocation table is necessarily acquired and performed an operation according to a logic operation (e.g., XOR logic operation), so as to obtain a decoded file allocation table via conversion (step S312). After obtaining the decoded file allocation table, the machine (or operating system) is capable of accessing the data stored in the memory card based on the decoded file allocation table and the data is not become messy resulting from the content in the file allocation table has ever been converted/decoded (step S314).
It is indicated that, the three checking steps of S300, S306 and S310 in the present embodiment have no particular order, and even it is unnecessary all of them are performed in the data access determination process for the memory card and the machine. In other words, for one example, the step S300 may be carried out after the steps S306 and S310, the step S306 may be carried out after the step S310 or only the steps S306 and S310 of the three steps are carried out. For another example, each two steps of the three steps S300, S306 and S310 are simultaneously carried out.
In summary, in the various embodiments of the present invention, the machine and the memory card are provided with special identification data for comparison, so that the memory card only permits to be accessed by a special machine. In addition, by way of converting a file allocation table, a possibility of data which is accessed at the unauthorized state is reduced. Due to the fact that the memory card is unable to be accessed by an arbitrary machine, the risk of data leak for the memory card is greatly reduced.
The foregoing description of the preferred embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form or to exemplary embodiments disclosed. Accordingly, the foregoing description should be regarded as illustrative rather than restrictive. Obviously, many modifications and variations will be apparent to practitioners skilled in this art. The embodiments are chosen and described in order to best explain the principles of the invention and its best mode practical application, thereby to enable persons skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use or implementation contemplated. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents in which all terms are meant in their broadest reasonable sense unless otherwise indicated. Therefore, the term “the invention”, “the present invention” or the like does not necessarily limit the claim scope to a specific embodiment, and the reference to particularly preferred exemplary embodiments of the invention does not imply a limitation on the invention, and no such limitation is to be inferred. The invention is limited only by the spirit and scope of the appended claims. The abstract of the disclosure is provided to comply with the rules requiring an abstract, which will allow a searcher to quickly ascertain the subject matter of the technical disclosure of any patent issued from this disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Any advantages and benefits described may not apply to all embodiments of the invention. It should be appreciated that variations may be made in the embodiments described by persons skilled in the art without departing from the scope of the present invention as defined by the following claims. Moreover, no element and component in the present disclosure is intended to be dedicated to the public regardless of whether the element or component is explicitly recited in the following claims.
Number | Date | Country | Kind |
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097103602 | Jan 2008 | TW | national |