JP6493258B2 - Storage control device, storage device, storage control method and program - Google Patents

Description

  The present invention relates to a storage control device, a storage device, a storage control method, and a program.

  In response to the growing demand for information security, highly confidential data such as confidential information held by companies and other organizations is required to be protected from threats such as confidentiality, integrity, and availability.

  WORM (Write Once Read Many) is known as one technique for preventing falsification of data stored in a storage device. When the protection by the WORM function is effective, once written information is protected so that it cannot be erased or altered. Data protection by the WORM function is used to protect data from editing, overwriting, erasing, etc., and plays a major role in maintaining the integrity of the data.

  Patent Document 1 describes a technology related to a WORM storage system that uses a large-capacity and relatively inexpensive disk in combination with a file system on a file server.

  Patent Document 2 describes a computer that protects data in a file, allows additional writing to the file, and protects data only in a specific range of the file.

JP-T-2006-524392 JP 2006-92276 A

  Even when the WORM function is effective, there is a possibility that the data is falsified during the period from the writing of data to the storage until the protection by the WORM function becomes effective. That is, there is a need for a storage device with higher safety against tampering or the like for the techniques described in each patent document.

  The present invention has been made in order to solve the above-described problems, and has as its main object to provide a storage device and the like that are highly secure against tampering and the like.

  The storage control device according to one aspect of the present invention finishes writing a file to the storage area and a WORM mode table that stores the WORM mode that defines the operation of the WORM function, which is set for each storage area of the storage device. And a control means for controlling to protect the file by the WORM function according to the definition of the WORM mode table.

  A storage device according to an aspect of the present invention includes a control unit that is a storage control device, and a storage unit that stores data.

  A storage control method according to an aspect of the present invention refers to a WORM mode table that stores a WORM mode that defines an operation of a WORM (Write Once Read Many) function, which is set for each storage area of a storage device. When the writing of the file ends, control is performed so that the file is protected by the WORM function in accordance with the WORM mode stored in the WORM mode table.

  A program according to an aspect of the present invention refers to a process of referring to a WORM mode table that stores a WORM mode that defines an operation of a WORM (Write Once Read Many) function that is set for each storage area of a storage device in a computer. When the writing of the file to the storage area is finished, a process for controlling the file to be protected by the WORM function according to the WORM mode stored in the WORM mode table is executed.

  According to the present invention, it is possible to provide a storage device or the like with high safety against tampering or the like.

It is a figure which shows the structure of the storage control apparatus and storage apparatus in the 1st Embodiment of this invention. It is a figure which shows an example of the metadata information linked | related with the file stored in the storage apparatus in the 1st Embodiment of this invention. It is a figure which shows an example of the WORM flag matched with the storage area of the storage apparatus in the 1st Embodiment of this invention. It is a figure which shows an example of the WORM mode table with which the storage control apparatus in the 1st Embodiment of this invention is provided. It is a figure which shows the example of a structure and operation | movement of a storage apparatus etc. which become a comparative example of this invention. It is a figure which shows an example of operation | movement of the storage control apparatus and storage apparatus in the 1st Embodiment of this invention. It is a flowchart which shows operation | movement of the storage control apparatus and storage apparatus in the 1st Embodiment of this invention. It is a figure which shows an example of the information processing apparatus which implement | achieves each apparatus in embodiment of this invention.

  Embodiments of the present invention will be described with reference to the accompanying drawings. In each embodiment of the present invention, each component of each device (system) represents a functional unit block. Some or all of the components of each device (system) may be realized by an arbitrary combination of an information processing device 500 and a program as shown in FIG. 8, for example. The information processing apparatus 500 includes the following configuration as an example.

CPU (Central Processing Unit) 501
ROM (Read Only Memory) 502
-RAM (Random Access Memory) 503
A program 504 loaded into the RAM 503
A storage device 505 for storing the program 504
A drive device 507 for reading / writing the recording medium 506
Communication interface 508 connected to the communication network 509
An input / output interface 510 for inputting / outputting data
-Bus 511 connecting each component
Each component of each device in each embodiment is realized by the CPU 501 acquiring and executing a program 504 that realizes these functions. The program 504 that realizes the function of each component of each device is stored in advance in the storage device 505 or the RAM 503, for example, and is read by the CPU 501 as necessary. Note that the program 504 may be supplied to the CPU 501 via the communication network 509 or may be stored in the recording medium 506 in advance, and the drive device 507 may read the program and supply it to the CPU 501.

  There are various modifications to the method of realizing each device. For example, each device may be realized by an arbitrary combination of the information processing device 500 and a program that are separately provided for each component. A plurality of constituent elements included in each device may be realized by an arbitrary combination of one information processing device 500 and a program.

  In addition, part or all of each component of each device is realized by a general-purpose or dedicated circuit including a processor or the like, or a combination thereof. These may be configured by a single chip or may be configured by a plurality of chips connected via a bus. Part or all of each component of each device may be realized by a combination of the above-described circuit and the like and a program.

  When some or all of the constituent elements of each device are realized by a plurality of information processing devices and circuits, the plurality of information processing devices and circuits may be centrally arranged or distributedly arranged. Also good. For example, the information processing apparatus, the circuit, and the like may be realized as a form in which each is connected via a communication network, such as a client and server system and a cloud computing system.

  First, a first embodiment of the present invention will be described. As shown in FIG. 1A, the storage apparatus 10 according to the first embodiment of the present invention includes a storage control apparatus 100 and a storage unit 110. As shown in FIG. 1B, the storage apparatus 10 according to the first embodiment of the present invention includes the storage control apparatus 100 and the storage unit 110 described above.

  When the control unit 101 of the storage control device 100 finishes writing the file to the storage area of the storage unit 110, the control unit 101 controls the file to be protected by the WORM function according to the WORM mode stored in the WORM mode table 102. . The WORM mode table 102 stores a WORM mode that defines the operation of the WORM function for each storage area of the storage unit 110. The control unit 101 may perform other control related to writing of a file to the other storage unit 110. The WORM mode table 102 is stored in a storage area of the storage unit 110, for example. However, the WORM mode table 102 may be stored in another device or the like as long as the control unit 101 can refer to it.

  The storage unit 110 includes one or more storage areas. In the present embodiment, a case where there is one storage area will be described as an example, but the number of storage areas may be plural. In the present embodiment, the validity or invalidity of the WORM function is set for each storage area.

  An arbitrary number of files 12 are stored in each storage area. In the example shown in FIG. 1B, a case where the file is one file 111 will be described as an example. Each file 111 is associated with metadata information 112. The metadata information 112 stores various information related to the associated file. FIG. 2 is a diagram illustrating an example of the metadata information 112. In the example illustrated in FIG. 2, the metadata information 112 stores information regarding access authority to the file such as writing to, reading from, and execution of the file, and information regarding the creation date and time of the file.

  Further, the WORM flag 113 is stored together with the file in the storage area where the WORM function is enabled. The WORM flag 113 is a table that stores a flag indicating whether the WORM function is valid or invalid for a file stored in a corresponding storage area.

  FIG. 3 shows an example of the WORM flag 113. In FIG. 3, “file name” is the name of the file managed by the WORM flag 113, and “flag type” indicates the state of the WORM function for each file. A flag “valid” or “invalid” is set in the “flag type” field. Then, the WORM function is validated for the file validated by the WORM flag 113. When the WORM function is enabled for a file, the file cannot be changed or deleted according to the above-described WORM mode. In the WORM flag 113 shown in FIG. 3, the WORM function for the files 2 and 3 is enabled.

  Next, the configuration and operation of the storage control device 100 in this embodiment will be described.

  The WORM mode table 102 stores a WORM mode that defines the operation of the WORM function for each storage area of the storage unit 110. In the present embodiment, it is assumed that there are two modes of “Once” and “Multi” as the WORM mode. Other modes may exist as the WORM mode. The WORM mode is determined according to the type and operation of application software that writes data to the storage area when the storage area is configured in the storage unit 110.

  In this embodiment, the “Once” WORM mode is a mode relating to a case where writing to one file is performed once. That is, the “Once” WORM mode is mainly used by application software that opens a file, writes data into the file, and closes the file when the writing is completed. The “Multi” WORM mode is a mode related to the case where writing can be performed a plurality of times for one file. That is, the WORM mode of “Multi” is mainly used for application software that opens a file and writes data to the file, closes the file, and then reopens the file and appends data.

  Note that “opening a file” refers to an operation for enabling writing to the file. This operation is realized by making it impossible to access the file from another process or the like, for example, by locking the file. Further, “closing a file” refers to an operation of finishing writing to the file and making writing impossible. This operation is realized by making it possible to access the file from another process or the like by, for example, releasing the lock described above. The closing of a file can be detected by returning a return value and a file handle, for example.

  Further, as described above, another mode of “Once” or “Multi” may exist as the WORM mode. For example, when a file (for example, a catalog file) other than backup data is created in the storage area of the storage unit 110, a mode in which only backup data is subject to protection by WORM in the storage area can be considered. In this case, for example, a file to be protected by WORM is distinguished by a file extension or the like.

  The control unit 101 performs control so that the file is protected by the WORM function in accordance with the definition of the WORM mode table 102. The control unit 101 validates the file protection by the WORM function when the writing of the file to the storage area of the storage unit 110 is finished. That is, when the file to be written is closed, the control unit 101 sets the flag type of the WORM flag 113 for the file to “valid”. Preferably, the control unit 101 sets the flag type for the file in the WORM flag 113 to “valid” simultaneously with closing of the file to be written.

  When the control unit 101 performs such control, it is possible to eliminate the time until the WORM function is validated after the file is written to the storage area. That is, it is possible to eliminate a period during which the WORM function is invalid after writing a file to the storage area. Therefore, it is possible to prevent falsification of the file from the file writing to the activation of the WORM function.

  The control unit 101 refers to the WORM mode table 102 when a file to be written is closed. Then, the control unit 101 validates the WORM function together with the closing of the file according to the mode defined in the WORM mode table 102 for the storage area in which the file is written. File protection by the WORM function is performed as follows according to the WORM mode stored in the WORM mode table 102 for each storage area.

  When the WORM mode is “Once”, the WORM function is enabled for the file, and any change or deletion operation to the entire file becomes impossible. This operation is the same as the protection by the general WORM function. In addition, since the control unit 101 enables the WORM function together with the closing of the file, it becomes impossible to tamper with the file between the writing of the file and the enabling of the WORM function.

  When the WORM mode is “Multi”, the WORM function is enabled for the file, and any change or deletion of the written contents of the file becomes impossible. Appending to the file is possible. By performing such control, when the application software repeatedly opens and closes the file and appends to the file, the written content can be protected by the above-described WORM function. In other words, even when additional writing is performed on a file, the security against tampering with respect to the written content is improved.

  Note that some or all of the functions of the control unit 101 described above may be provided in a device that accesses the storage device 10, that is, a device that is a client for the storage device 10.

  Next, the operation of the storage device 10 or the storage control device 100 in this embodiment is compared with a comparative example that performs other operations for WORM protection.

  FIG. 5 shows an example of the storage apparatus 20 as a comparative example and its operation. The storage device 20 includes a storage control device 200 and a storage unit 210. The storage control device 200 includes a control unit 201. The control unit 201 controls to protect the file written in the storage unit 210 by the WORM function. The storage unit 210 has basically the same configuration as the storage unit 110 in the present embodiment. The file 211, metadata information 212, and WORM flag 213 correspond to the file 111, metadata information 112, and WORM1 lag 213 in the present embodiment, respectively.

  In the comparative example, after the writing to the file in the storage unit 210 ends, the control unit 201 validates the protection by the WORM function for the file when the right to write to the file is deleted. That is, the control unit 201 validates the WORM function for a file written to the storage unit 210 by a procedure different from that of the control unit 101. Further, the storage control device 200 does not include an element corresponding to the WORM mode table 102. That is, the storage apparatus 200 does not perform control based on the above-described WORM mode.

  In the comparative example, when the protection of the file by the WORM function is validated, the storage device 20 or the like generally operates as follows.

  First, a file write request is made to the storage apparatus 20 from application software or the like executed on the client apparatus (corresponding to (1) in FIG. 5). In the storage device 20, a file is written to the storage unit 210 based on the control of the control unit 201. When the file is written, the write authority for the file is deleted based on the instruction from the above-described application software (corresponding to (2) in FIG. 5).

  Along with the deletion of the write authority for the file, the control unit 201 controls to protect the file by the WORM function (corresponding to (3) in FIG. 5). That is, the control unit 201 sets the WORM flag for the file to “valid”. The operation of the control unit 201 makes it impossible to change or delete the file.

  However, in the above-described operation example of the storage apparatus 20 of the comparative example, as described above, the operation corresponding to (1) and (2) in FIG. 5 is performed based on an instruction from an apparatus serving as an external client. Is called. Therefore, there is a possibility that a time lag occurs after the file is written in the storage unit 210 until the protection by the WORM function becomes effective. That is, an external attacker may refer to or alter the file after the file is written in the storage unit 210 until protection by the WORM function becomes effective ((4 in FIG. 5). )).

  On the other hand, the storage control device 100 of the storage device 10 in the present embodiment generally operates as follows when the protection of the file by the WORM function is validated.

  As described above, the WORM mode table 102 stores, for each storage area of the storage unit 110, a WORM mode that is determined according to the operation of application software that performs writing to the storage area. Yes. The control unit 101 refers to the WORM mode determined for each storage area as necessary (corresponding to (1) in FIG. 6).

  In a situation where the WORM mode is set for each storage area, a file is written in response to a file write request to the storage apparatus 10 from application software or the like executed on the client apparatus ((( Equivalent to 2)).

  Then, the control unit 101 enables the WORM flag when the file writing is completed and the file is closed (corresponding to (3) in FIG. 6). As described above, the control unit 101 performs such an operation, so that it is possible to eliminate a period in which the WORM function is invalid after writing a file to the storage area. That is, unlike the storage device 20, there is no time lag from when the file is written to the storage unit 110 until the protection by the WORM function becomes effective. Therefore, it is impossible for an external attacker to refer to or alter the file (corresponding to (4) in FIG. 6).

  Next, the operation of the storage apparatus 10 or the storage control apparatus 100 in this embodiment will be described using the flowchart shown in FIG.

  First, the control unit 101 of the storage control device 100 refers to the WORM mode table 102 and acquires the WORM mode of the storage area to be written (step S101).

  Next, the control unit 101 writes a file in a target storage area in response to a request from application software or the like executed by a device or the like serving as a client (step S102).

  Next, the control unit 101 validates the WORM flag in conjunction with the closing of the file written in step S102 (step S103). The control unit 101 validates the WORM flag according to the mode set in the WORM mode table 102 for the storage area in which the file is written.

  As described above, in the storage apparatus 10 according to the first embodiment of the present invention, when the control unit 101 of the storage control apparatus 100 finishes writing the file to the storage area, the file is protected by the WORM function. Control. The control unit 101 validates the WORM function together with the closing of the file. There is no time lag from when the file is written to the storage unit 110 until the protection by the WORM function becomes effective. For this reason, it is possible to prevent falsification of the file between the writing of the file and the activation of the WORM function.

  In the storage apparatus 10 according to the first embodiment of the present invention, the WORM function is validated according to the WORM mode. In the present embodiment, modes are assumed for the case where writing to one file is performed once and the case where writing can be performed a plurality of times on one file. By enabling the WORM function based on the WORM mode, the file can be protected in the operation of application software that writes the file to the storage apparatus 10.

  Therefore, the storage control device 100 according to the present embodiment makes it possible to improve safety against tampering of the storage device. In addition, the storage apparatus 10 in the present embodiment is a storage apparatus with high safety against tampering or the like.

  The present invention has been described above with reference to the embodiments, but the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention. The configurations in the embodiments can be combined with each other without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 10 Storage apparatus 100 Storage control apparatus 101 Control part 102 WORM mode table 110 Storage part 111 File 112 Metadata information 113 WORM flag 500 Information processing apparatus 501 CPU
502 ROM
503 RAM
504 Program 505 Storage device 506 Recording medium 507 Drive device 508 Communication interface 509 Communication network 510 Input / output interface 511 Bus

Claims (7)

A WORM mode table that stores a WORM mode that defines the operation of a WORM (Write Once Read Many) function, which is set for each storage area of the storage device;
Control means for controlling the file to be protected by the WORM function according to the WORM mode stored in the WORM mode table when the writing of the file to the storage area is terminated;
The storage control apparatus, wherein the control means controls to perform protection by the WORM function when the file is closed, and validates a flag type of a WORM flag stored together with the file in the storage area.   2. The storage control apparatus according to claim 1, wherein the control means makes it impossible to change or delete the entire file when the WORM mode indicates that writing to one file is once.   2. The control unit according to claim 1, wherein when the WORM mode indicates that writing can be performed a plurality of times for one file, it is impossible to change or delete the file at a written position. The storage control device described.   4. The control unit according to claim 1, wherein the control unit controls the file to be protected by the WORM function by enabling a WORM flag provided for the file. 5. Storage controller. Control means that is the storage control device according to any one of claims 1 to 4,
A storage device comprising storage means for storing data. A storage control method in a storage control device,
The storage control device
Refer to the WORM mode table that stores the WORM mode that defines the operation of the WORM (Write Once Read Many) function, which is set for each storage area of the storage device.
When writing of the file to the storage area is completed, control is performed so that the file is protected by the WORM function according to the WORM mode stored in the WORM mode table;
Storage control for validating the flag type of the WORM flag stored in the storage area together with the file as control for protecting the file by the WORM function when the file is closed when the writing of the file is finished Method. On the computer,
A process of referring to a WORM mode table storing a WORM mode that defines the operation of a WORM (Write Once Read Many) function, which is set for each storage area of the storage device;
A process of controlling the file to be protected by the WORM function according to the WORM mode stored in the WORM mode table when the writing of the file to the storage area is terminated;
A process for validating the flag type of the WORM flag stored together with the file in the storage area as control to protect the WORM function when the file is closed at the end of writing of the file ; A program that executes

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