File management method and system of mobile storage medium under linux and medium

Abstract

The application discloses a kind of file management and control method, system and medium of mobile storage medium under Linux, the application includes after detecting that there is the target mobile storage medium of owner access this terminal, judge whether this terminal is the owner of target mobile storage medium, if owner then the complete file in target mobile storage medium is mounted to terminal and provides complete access authority;If not owner, according to the preset file management and control strategy, determine the accessible file of this terminal and its access authority in the complete file in target mobile storage medium, and the accessible file of this terminal is mounted to this terminal according to its access authority.The application can realize the classification security control of mobile storage medium based on the identification of owner and non-owner, and the access authority control between terminal and file of non-owner mobile storage medium can be easily realized by file management and control strategy, and the granularity of authority management is refined to file level, with the advantages of safety and reliability.

Description

Technical Field

[0001] This invention relates to the field of mobile storage media security management technology in the computer field, specifically to a file-level permission control method, system, and medium for mobile storage media. Background Technology

[0002] With the increasingly severe situation of information security, users involved in production and operation are paying more and more attention to information confidentiality. From small portable USB flash drives to large-scale storage servers, all have certain information security risks. To improve the security of file transfer, the common practice is to formulate strict rules and regulations and strengthen access control. Portable storage media are an important component of file transfer and have fully open access characteristics. This strategy is too coarse and cannot provide fine-grained control. Therefore, it is necessary to improve the file-level access control strategy based on portable storage media.

[0003] Currently, there are two main methods for managing mobile storage media: 1. Port-level management: This method controls the permissions of the terminal's peripheral ports to meet the management needs of mobile storage peripherals. 2. Mobile storage device management: This method records the unique identifier of the storage device along with the management policy. When the mobile storage device is inserted into the terminal, it is identified and managed using the corresponding management policy. These methods have the following shortcomings: ① The management granularity is relatively coarse, only providing control up to the mobile storage device level. More granular management policies cannot be met. For the terminal, files on the mobile storage medium are treated the same as ordinary files in the system, using the default management policy for ordinary files, such as the commonly used "read," "write," and "execute" permissions. However, mobile storage media also possess a characteristic that ordinary files on the terminal do not have—portability. Users can freely connect the mobile storage medium to any terminal, which is the main reason why the flow of confidential documents cannot be effectively controlled through administrative means. ② Management policies are terminal-dependent, only allowing the local terminal to formulate management policies for mobile storage peripherals. Once the mobile storage medium is connected to another terminal, the policy immediately becomes invalid. This situation makes it impossible to guarantee that data will not be illegally copied or used, and the lack of control over permissions leads to management vulnerabilities during file transfer. ③ The control policy originates from the terminal, but the users of removable storage media are not fixed, resulting in a chaotic control policy. The removable storage media cannot know who owns it or who can issue access policies for it. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a file-level permission control method, system and medium for mobile storage media, which addresses the above-mentioned problems of the prior art. The present invention can realize classified security control of mobile storage media based on the identification of owner and non-owner. Through file management strategy, access permission control between terminals and files of non-owner mobile storage media can be easily realized. Moreover, the granularity of permission control is refined to the file level, which has the advantages of security and reliability.

[0005] By saving policy data to a removable storage medium, the management policy follows the removable storage medium. At the same time, different roles are preset to distribute and implement file management policies on the removable storage medium.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] A file management method for removable storage media under Linux includes: after detecting that a target removable storage media with an owner is connected to the terminal, determining whether the terminal is the owner of the target removable storage media; if it is the owner, mounting all files in the target removable storage media to the terminal and providing full access permissions; if it is not the owner, determining the accessible files and their access permissions of the terminal among all files in the target removable storage media according to a preset file management policy, and mounting the accessible files of the terminal to the terminal according to their access permissions.

[0008] Optionally, after mounting the accessible files of this terminal to this terminal according to their access permissions, the method further includes obtaining, through interaction, a write request initiated by the user of this terminal for a target file with read-only access permissions in the accessible files of this terminal, generating an application item based on the write request and associating it with the target mobile storage medium; after mounting all files in the target mobile storage medium to the terminal and providing full access permissions, the method further includes, if there are unprocessed application items in the target mobile storage medium, obtaining the user's review result for the application item through interaction, and if the review result is that access to the target file is allowed, updating the file management policy so that the terminal corresponding to the application item has read and write access permissions to the target file.

[0009] Optionally, after mounting the accessible files of this terminal to this terminal according to their access permissions, the method further includes generating an audit item for the new file and associating it with the target mobile storage medium when the user writes a new file to the target mobile storage medium; after mounting all files in the target mobile storage medium to the terminal and providing full access permissions, the method further includes obtaining the user's permission settings for the new file corresponding to the audit item through interaction when there are unprocessed audit items in the target mobile storage medium. The permission settings include terminal information such as read / write access and readability for the new file, and the permission settings are appended to the file management policy.

[0010] Optionally, after mounting all files in the target removable storage medium to the terminal and providing full access permissions, the process further includes obtaining the user's active permission settings for specified files in the target removable storage medium through interaction. The active permission settings include terminal information such as read / write access and readability for the specified files, and updating the permission settings for the specified files in the file management policy based on the active permission settings.

[0011] Optionally, mounting the accessible files of this terminal to this terminal according to their access permissions includes: first, mounting the target removable storage medium to the isolated system mount point in the Linux system namespace of this terminal; then, using the sharing option of the mount command to mount the accessible files of this terminal in the target removable storage medium to different locations in the Linux system namespace according to their access permissions; and then propagating them to the Linux system namespace of this terminal.

[0012] Optionally, the step of detecting that a target mobile storage medium with an owner is connected to the terminal includes: after the target mobile storage medium is connected to the terminal, detecting whether the target mobile storage medium has an owner; if the target mobile storage medium has an owner, determining that a target mobile storage medium with an owner has been connected to the terminal; if the target mobile storage medium has no owner, firstly determining through interaction whether it is necessary to bind the target mobile storage medium to the terminal; if it is necessary to bind the target mobile storage medium to the terminal, then performing a binding operation to bind the target mobile storage medium to the terminal; then mounting all files in the target mobile storage medium to the terminal and providing full access permissions.

[0013] Optionally, the binding operation of binding the target removable storage medium to this terminal includes:

[0014] S101, perform security authentication on the user of this terminal. If the security authentication is successful, proceed to step S102; otherwise, end.

[0015] S102, obtain the hardware serial number of this terminal, encrypt the hardware serial number of this terminal using the public key to generate identifier ciphertext information, and sign the identifier ciphertext information using the private key to obtain signature information;

[0016] S103, store the public key, the identifier ciphertext information, and the signature information in a specified location on the target removable storage medium.

[0017] Optionally, determining whether the terminal is the owner of the target removable storage medium includes:

[0018] S201, use the private key to sign a specified piece of data to obtain test signature information, and use the public key stored on the target mobile storage medium to verify the signature information. If the verification fails, it is determined that this terminal is not the owner of the target mobile storage medium, and the process ends and exits; otherwise, proceed to step S202.

[0019] S202, use the public key stored on the target mobile storage medium to verify the signature information of the encrypted information. If the verification fails, it is determined that this terminal is not the owner of the target mobile storage medium, and the process ends and exits; otherwise, proceed to step S203.

[0020] S203, use the private key to decrypt the ciphertext information of the identifier stored on the target mobile storage medium to obtain the owner's hardware serial number and obtain the hardware serial number of this terminal. If the owner's hardware serial number and the hardware serial number of this terminal match, it is determined that this terminal is the owner of the target mobile storage medium; otherwise, it is determined that this terminal is not the owner of the target mobile storage medium.

[0021] In addition, the present invention also provides a file management system for removable storage media under Linux, including a microprocessor and a memory interconnected thereto, wherein the microprocessor is programmed or configured to execute the file management method for removable storage media under Linux.

[0022] Furthermore, the present invention also provides a computer-readable storage medium storing a computer program, the computer program being programmed or configured by a microprocessor to execute the file management method for the removable storage medium under Linux.

[0023] Compared with the prior art, the present invention has the following advantages: The file management method for removable storage media under Linux of the present invention can realize the classification and security control of removable storage media based on the identification of owner and non-owner. Through the file management strategy, access permission control between terminals and files of non-owner removable storage media can be easily realized, and the granularity of permission control is refined to the file level, which has the advantages of security and reliability. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the basic process of the method in Embodiment 1 of the present invention.

[0025] Figure 2 This is a flowchart illustrating the binding operation in Embodiment 1 of the present invention.

[0026] Figure 3 This is a schematic diagram of the owner determination process in Embodiment 1 of the present invention.

[0027] Figure 4 This is a schematic diagram of the basic process of the method in Embodiments 2 to 4 of the present invention. Detailed Implementation

[0028] Example 1:

[0029] like Figure 1 As shown, the file management method for removable storage media under Linux in this embodiment includes: after detecting that a target removable storage media with an owner is connected to the terminal, determining whether the terminal is the owner of the target removable storage media; if it is the owner, mounting all files in the target removable storage media to the terminal and providing full access permissions; if it is not the owner, determining the accessible files and their access permissions for the terminal among all files in the target removable storage media according to a preset file management policy, and mounting the accessible files to the terminal according to their access permissions. In this embodiment, the file management policy is used to determine the access permissions of a specified terminal to a specified file. Each record includes the file name, file path, terminal, and permissions. Permissions are divided into three types: "hidden," "read-only," and "read-write." "Read-only" and "read-write" are accessible files, while "hidden" is an inaccessible file. The default policy can be selected as needed; for example, in this embodiment, the default policy is "hidden."

[0030] In this embodiment, the file management strategy is to store the file on the target mobile storage medium to achieve offline file management. Alternatively, the file can be stored in a specified network location to achieve online file management, or a combination of network location and local caching can be used to achieve semi-offline file management.

[0031] In this embodiment, mounting accessible files on the terminal according to their access permissions includes: first, mounting the target removable storage medium to an isolated system mount point in the terminal's Linux system namespace; then, using the `make-shared` option of the `mount` command to mount the accessible files on the target removable storage medium to different locations in the Linux system namespace according to their access permissions, and then propagating them to the terminal's own Linux system namespace. The Linux system namespace is a resource isolation mechanism provided by the Linux kernel system, which can isolate host resources such as files and networks. In this embodiment, mounting the target removable storage medium to the isolated system mount point in the terminal's Linux system namespace includes using the `clone` system call to establish data isolation between the terminal system and the Linux system namespace; then, reading the file management policy database from the removable storage medium; and using the `make-shared` option of `mount` to mount the files on the removable storage medium to other locations in the namespace, propagating them to the terminal system namespace to implement file management policies.

[0032] like Figure 1 As shown, in this embodiment, before detecting that a target mobile storage medium with an owner is connected to the terminal, the process includes: after the target mobile storage medium is connected to the terminal, detecting whether the target mobile storage medium has an owner; if the target mobile storage medium has an owner, it is determined that a target mobile storage medium with an owner has been connected to the terminal; if the target mobile storage medium has no owner, it is first determined interactively whether the target mobile storage medium needs to be bound to the terminal; if it needs to be bound to the terminal, the binding operation of binding the target mobile storage medium to the terminal is performed; then all files in the target mobile storage medium are mounted to the terminal and full access permissions are provided. Through the above method, the attributes of the mobile storage medium can be automatically distinguished, and the management and non-management behaviors of the target mobile storage medium can be restricted and distinguished.

[0033] In this embodiment, the binding operation of attaching the target removable storage medium to this terminal and related security operations are all implemented using a set of public and private key pairs. For example... Figure 2 As shown, the binding operation of binding the target mobile storage medium to this terminal in this embodiment includes:

[0034] S101, perform security authentication on the user of this terminal. If the security authentication is successful, proceed to step S102; otherwise, end.

[0035] S102, obtain the hardware serial number of this terminal, encrypt the hardware serial number of this terminal using the public key to generate identifier ciphertext information, and sign the identifier ciphertext information using the private key to obtain signature information;

[0036] S103, store the public key, the identifier ciphertext information, and the signature information in a specified location on the target removable storage medium.

[0037] It should be noted that: First, the security authentication in step S101 can adopt the required authentication method as needed. It can be an authentication method bound to the operating system or an authentication method independent of the operating system. For example, as an optional implementation, this embodiment uses a security question method, and the security question in step S101 is the default security question. Only a correct answer will result in successful security authentication. Second, the hardware serial number is generated based on hardware information. The hardware information can be part or all of the hardware information such as CPU serial number, network card MAC address, hard drive serial number, motherboard serial number, etc. The generation method can be concatenation, encryption, etc., as long as it can ensure that the obtained hardware serial number is unique or substantially non-duplicate.

[0038] like Figure 3 As shown, in this embodiment, determining whether the terminal is the owner of the target removable storage medium includes:

[0039] S201, use the private key to sign a specified piece of data to obtain test signature information, and use the public key stored on the target mobile storage medium to verify the signature information. If the verification fails, it is determined that this terminal is not the owner of the target mobile storage medium, and the process ends and exits; otherwise, proceed to step S202.

[0040] S202, use the public key stored on the target mobile storage medium to verify the signature information of the encrypted information. If the verification fails, it is determined that this terminal is not the owner of the target mobile storage medium, and the process ends and exits; otherwise, proceed to step S203.

[0041] S203, use the private key to decrypt the ciphertext information of the identifier stored on the target mobile storage medium to obtain the owner's hardware serial number and obtain the hardware serial number of this terminal. If the owner's hardware serial number and the hardware serial number of this terminal match, it is determined that this terminal is the owner of the target mobile storage medium; otherwise, it is determined that this terminal is not the owner of the target mobile storage medium.

[0042] Furthermore, this embodiment also provides a file management system for removable storage media under Linux, including a microprocessor and a memory interconnected, wherein the microprocessor is programmed or configured to execute the aforementioned file management method for removable storage media under Linux. Additionally, this embodiment also provides a computer-readable storage medium storing a computer program, which is used to be programmed or configured by the microprocessor to execute the aforementioned file management method for removable storage media under Linux.

[0043] Example 2:

[0044] This embodiment is basically the same as Embodiment 1, the main difference being that the file management strategy in Embodiment 1 is a fixed strategy, while the file management strategy in this embodiment is an updatable file management strategy.

[0045] As an optional implementation, this embodiment includes policy updates for read-only files. See also... Figure 4 As shown in 'a', in this embodiment, after mounting the accessible files of this terminal to this terminal according to their access permissions, it also includes obtaining, through interaction, a write request initiated by the user of this terminal for a target file with read-only access permissions in the accessible files of this terminal. Based on the write request, an application item is generated and associated with the target mobile storage medium. In this embodiment, the information of the application item includes name, host information, application file path, and application reason. After mounting all files in the target mobile storage medium to the terminal and providing complete access permissions, it also includes obtaining the user's review result for the application item through interaction when there are unprocessed application items on the target mobile storage medium. If the review result is that access to the target file is allowed, the file management policy is updated so that the terminal corresponding to the application item has read and write access permissions to the target file.

[0046] Furthermore, to enhance the security of document management policy updates, security authentication can be performed on the user of this terminal before obtaining the user's review result for the application through interaction. If the security authentication is successful, the user's review result for the application will be obtained interactively; otherwise, the process ends. Security authentication can employ the required authentication method as needed, including either operating system-bound or operating system-independent methods. For example, as an optional implementation, this embodiment uses a security question approach. In embodiment one, step S103 further includes setting a security question and answer, generating a hash value for the answer, and storing it in the target removable storage medium. Security authentication is only successful when the hash value of the security question's answer matches the stored hash value.

[0047] Furthermore, this embodiment also provides a file management system for removable storage media under Linux, including a microprocessor and a memory interconnected, wherein the microprocessor is programmed or configured to execute the aforementioned file management method for removable storage media under Linux. Additionally, this embodiment also provides a computer-readable storage medium storing a computer program, which is used to be programmed or configured by the microprocessor to execute the aforementioned file management method for removable storage media under Linux.

[0048] Example 3:

[0049] This embodiment is a further improvement on Embodiment 2, and includes a policy update trigger for writing new files. See also... Figure 4 In step b, after mounting the accessible files of this terminal to this terminal according to their access permissions, it also includes generating an audit item for the new file and associating it with the target mobile storage medium when the user writes a new file to the target mobile storage medium; after mounting all files in the target mobile storage medium to the terminal and providing full access permissions, it also includes obtaining the user's permission settings for the new file corresponding to the audit item through interaction when there are unprocessed audit items in the target mobile storage medium. The permission settings include terminal information for read / write and readable new files, and the permission settings are appended to the file management policy.

[0050] Furthermore, this embodiment also provides a file management system for removable storage media under Linux, including a microprocessor and a memory interconnected, wherein the microprocessor is programmed or configured to execute the aforementioned file management method for removable storage media under Linux. Additionally, this embodiment also provides a computer-readable storage medium storing a computer program, which is used to be programmed or configured by the microprocessor to execute the aforementioned file management method for removable storage media under Linux.

[0051] Example 4:

[0052] This embodiment is a further improvement on Embodiment 2. The file management policy in this embodiment is an updatable file management policy. As an optional implementation, this embodiment includes proactive updates to the file management policy. See also... Figure 4 As shown in c, after mounting all files in the target removable storage medium to the terminal and providing full access permissions, the process also includes obtaining the user's active permission settings for specified files in the target removable storage medium through interaction. The active permission settings include terminal information such as read / write access and readability for the specified files, and updating the permission settings for the specified files in the file management policy based on the active permission settings.

[0053] Furthermore, this embodiment also provides a file management system for removable storage media under Linux, including a microprocessor and a memory interconnected, wherein the microprocessor is programmed or configured to execute the aforementioned file management method for removable storage media under Linux. Additionally, this embodiment also provides a computer-readable storage medium storing a computer program, which is used to be programmed or configured by the microprocessor to execute the aforementioned file management method for removable storage media under Linux.

[0054] It should be noted that the three update methods of the file management strategy in Examples 2 to 4 are not dependent on each other. Therefore, the order can be adjusted as needed, or some or all of them can be selected for combination and implementation.

[0055] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-readable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the process. Figure 1 One or more processes and / or boxes Figure 1The computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0056] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A file management method for removable storage media under Linux, characterized in that, include: After detecting that a target removable storage medium with an owner has been connected to this terminal, it determines whether this terminal is the owner of the target removable storage medium. If it is the owner, all files in the target removable storage medium are mounted to the terminal and full access permissions are provided. If it is not the owner, according to the preset file management policy, the accessible files and their access permissions of this terminal are determined among all files in the target removable storage medium, and the accessible files of this terminal are mounted to this terminal according to their access permissions. The process before detecting that a target mobile storage medium with an owner has been connected to the terminal includes: after the target mobile storage medium is connected to the terminal, detecting whether the target mobile storage medium has an owner; if the target mobile storage medium has an owner, determining that a target mobile storage medium with an owner has been connected to the terminal; if the target mobile storage medium has no owner, firstly determining through interaction whether it is necessary to bind the target mobile storage medium to the terminal; if it is necessary to bind the target mobile storage medium to the terminal, then performing the binding operation of binding the target mobile storage medium to the terminal; then mounting all files in the target mobile storage medium to the terminal and providing full access permissions. The binding operation of binding the target removable storage medium to this terminal includes: S101, perform security authentication on the user of this terminal. If the security authentication is successful, proceed to step S102; otherwise, end. S102, obtain the hardware serial number of this terminal, encrypt the hardware serial number of this terminal using the public key to generate identifier ciphertext information, and sign the identifier ciphertext information using the private key to obtain signature information; S103, store the public key, the identifier ciphertext information, and the signature information in a specified location on the target removable storage medium.

2. The file management method for removable storage media under Linux according to claim 1, characterized in that, After mounting the accessible files of this terminal to this terminal according to their access permissions, the process further includes obtaining, through interaction, a write request initiated by the user of this terminal for a target file with read-only access permissions among the accessible files of this terminal, generating an application item based on the write request and associating it with the target mobile storage medium; after mounting all files in the target mobile storage medium to the terminal and providing full access permissions, the process further includes, if there are unprocessed application items on the target mobile storage medium, obtaining the user's review result for the application item through interaction, and if the review result allows access to the target file, updating the file management policy so that the terminal corresponding to the application item has read and write access permissions to the target file.

3. The file management method for removable storage media under Linux according to claim 2, characterized in that, After mounting the accessible files of this terminal to this terminal according to their access permissions, the method further includes generating an audit item for the new file and associating it with the target mobile storage medium when the user writes a new file to the target mobile storage medium; after mounting all files in the target mobile storage medium to the terminal and providing full access permissions, the method further includes obtaining the user's permission settings for the new file corresponding to the audit item through interaction when there are unprocessed audit items on the target mobile storage medium. The permission settings include terminal information such as read / write access and readability for the new file, and the permission settings are appended to the file management policy.

4. The file management method for removable storage media under Linux according to claim 1, characterized in that, After mounting all files in the target removable storage medium to the terminal and providing full access permissions, the process also includes obtaining the user's active permission settings for specified files in the target removable storage medium through interaction. The active permission settings include terminal information such as read / write access and readability for the specified files, and updating the permission settings for the specified files in the file management policy based on the active permission settings.

5. The file management method for removable storage media under Linux according to claim 1, characterized in that, The process of mounting accessible files of this terminal to this terminal according to their access permissions includes: first, mounting the target removable storage medium to the isolated system mount point in the Linux system namespace of this terminal; then, using the sharing option of the mount command to mount the accessible files of this terminal in the target removable storage medium to different locations in the Linux system namespace according to their access permissions, and then propagating them to the Linux system namespace of this terminal.

6. The file management method for removable storage media under Linux according to claim 1, characterized in that, The determination of whether this terminal is the owner of the target mobile storage medium includes: S201, use the private key to sign a specified piece of data to obtain test signature information, and use the public key stored on the target mobile storage medium to verify the signature information. If the verification fails, it is determined that this terminal is not the owner of the target mobile storage medium, and the process ends and exits; otherwise, proceed to step S202. S202, use the public key stored on the target mobile storage medium to verify the signature information of the encrypted information. If the verification fails, it is determined that this terminal is not the owner of the target mobile storage medium, and the process ends and exits; otherwise, proceed to step S203. S203, use the private key to decrypt the ciphertext information of the identifier stored on the target mobile storage medium to obtain the owner's hardware serial number and obtain the hardware serial number of this terminal. If the owner's hardware serial number and the hardware serial number of this terminal match, it is determined that this terminal is the owner of the target mobile storage medium; otherwise, it is determined that this terminal is not the owner of the target mobile storage medium.

7. A file management system for removable storage media under Linux, comprising a microprocessor and a memory interconnected, characterized in that, The microprocessor is programmed or configured to perform the file management method for removable storage media under Linux as described in any one of claims 1 to 6.

8. A computer-readable storage medium storing a computer program, characterized in that, The computer program is used to be programmed or configured by a microprocessor to execute the file management method for removable storage media under Linux as described in any one of claims 1 to 6.

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