JPH05224828A - Method for controlling external storage device and information processor - Google Patents

Abstract

PURPOSE:To enable both the secrecy holding and data protection of storage contents and the effective utilization of the resources of storage media by inhabiting a general external storage device from being read, written, or initialized in storage units. CONSTITUTION:The contents of an address storage means 14 storing the call address of an external storage device control means 7 are altered to substitute the calling of the external storage control means 7 with the calling of an access control means 28 and then the access control means 28 is called at a request for external storage device control. The access control means 28 inhibits the storage units from being read out (or written or initialized), one by one, according to attributes which are stored in an attribute storage means 27 and indicate whether the reading (or writing or initialization) of the storage units is allowed or inhibited in the storage units. Consequently, the reading (or writing or initialization) inhibition can be controlled in the storage units.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to prohibiting reading of contents stored in an external storage device connected to an information processing device.
The present invention relates to an external storage control method and an information processing apparatus suitable for keeping confidentiality of stored contents or protecting data by setting write prohibition and initialization prohibition.

[0002]

2. Description of the Related Art FIG. 6 is a block diagram showing the configuration of a conventional information processing apparatus. In FIG. 6, 1 is a CPU, 3 is a keyboard control unit, 4 is a keyboard, and 5 is a display body CR.
T control unit, 6 is a display CRT, 7 is an external storage device control unit, 8 is an internal floppy disk device, 9 is an additional floppy disk device, 10 is an internal hard disk device, 1
1 is an additional hard disk device, 12 is RAM, 13 is R
OM, 14 is an address storage unit, 15 is a calling unit, and 2 and 16 to 25 are bus lines.

As a conventional technique for realizing confidentiality protection of data stored in an external storage device or data protection, Japanese Patent Laid-Open Publication No. Sho.
As described in Japanese Patent Publication No. 55-22218, there is a magnetic disk device in which data read prohibition, write prohibition, or both are set by a keyed switch. In such a device, confidentiality is maintained by prohibiting reading, data is protected by prohibiting writing, and confidentiality and data are protected by prohibiting both. Further, as described in Japanese Patent Laid-Open No. 61-39263, there is one in which prohibition or permission is set for each sector only for writing. In such a device,
Sectors other than the write-protected sector can be written and read, and the remaining sectors can be effectively utilized while realizing the data protection of the designated sector.

Further, as described in JP-A-3-3159,
There is one that stores a prohibition or permission attribute regarding reading, writing, or both for each sector, track, cylinder, or variable-length storage unit, and controls reading, writing, or both according to the stored attribute. In such a device, it is possible to maintain both confidentiality of stored contents and data protection and effective use of resources of the storage medium.

In each of the above publications, the internal storage device such as the built-in floppy disk device 8, the expanded floppy disk device 9, the built-in hard disk device 10 or the expanded hard disk device 11 is given special consideration and sent from the host computer. The determination of whether or not to process the given command or data (prohibition or permission of access) is performed inside the external storage device, thereby realizing confidentiality protection of stored contents or data protection.

[0006]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the device described in Japanese Patent Laid-Open Publication No. 2003-242242, data reading, writing, or both are set for each magnetic disk device, so that confidentiality of stored contents and data protection cannot be achieved at the same time as effective use of storage medium resources. There was a point.

Further, in the device described in Japanese Patent Laid-Open No. 61-39263, there is a problem in that the confidentiality of the stored contents cannot be maintained because only prohibition or permission can be set for writing.

Further, there is a device described in Japanese Patent Laid-Open No. 3-3159, which realizes both confidentiality protection of stored contents and data protection and effective utilization of resources of a storage medium, which is attributed to a magnetic storage device. A general magnetic storage device which has a storage means and an access control means as its main purpose and does not have an attribute storage means and an access control means, protects stored contents confidentially and protects data, and effectively uses resources of a storage medium. It is not something that tries to achieve both utilization.

It is an object of the present invention to protect a stored content and protect data by enabling a general external storage device to prohibit reading, writing and initialization for each storage unit. It is to make effective use of medium resources.

[0010]

According to the present invention, an external storage device control means for sending an instruction to an external storage device to control the external storage device, an address storage means for storing an address of the external storage device control means, and In an information processing device including a calling unit for calling the external storage device control unit according to the information of the address storage unit, an attribute storage unit that stores a read attribute indicating whether reading is permitted or prohibited for each storage unit, According to the read attribute stored in the attribute storage means, access control means for permitting or prohibiting reading for each storage unit, and the contents of the address storage means are changed to call the external storage device control means by the access control means. Read-out from the external storage device, and a switching means for switching to calling Further, an external storage device control means for sending a command to the external storage device to control the external storage device, an address storage means for storing an address of the external storage device control means, and information of the address storage means. In the information processing device, comprising: a calling unit for calling the external storage device control unit according to the above, an attribute storage unit that stores a writing attribute indicating whether writing is permitted or prohibited for each storage unit; Access control means for permitting or prohibiting writing for each storage unit according to the attribute of writing to be stored;
And a switching unit for changing the content of the address storage unit to switch the call of the external storage device control unit to the call of the access control unit, and control writing to the external storage device. The external storage device control means for sending an instruction to the external storage device to control the external storage device, the address storage means for storing the address of the external storage device control means, and the external storage device control means according to the information of the address storage means. In an information processing device including a calling unit for calling,
According to an attribute storage unit that stores an initialization attribute indicating whether initialization is permitted or prohibited for each storage unit, and the initialization attribute for each storage unit is permitted or prohibited according to the initialization attribute stored in the attribute storage unit. Access control means for changing the contents of the address storage means and switching means for switching the call of the external storage device control means to the call of the access control means, and controlling the initialization of the external storage device. Characteristically, in particular, the storage unit is
It is characterized in that it is one of a sector unit, a track unit, a cylinder unit, or a unit unit, and further comprises an attribute designating unit for designating addition or deletion of information stored in the attribute storage unit. To do.

[0011]

According to the present invention, the content of the address storage means for storing the call address of the external storage device control means is changed, and the call of the external storage device control means is replaced with the call of the access control means which will be described later. When a device control request is issued, the access control means, which is one of the constituent elements of the present invention, is called. The access control means reads (or writes, or initializes) each storage unit stored in the attribute storage means.
Depending on the attribute of permission or prohibition, read (or write, or initialization) for each storage unit is permitted or prohibited. This makes it possible to control read (or write, or initialization) inhibition for each storage unit.

[0012]

【Example】

(Embodiment 1) FIG. 1 is a block diagram showing the configuration of an information processing apparatus of the present invention to which basic peripheral devices are connected. Fifty
Is an information processing device of the present invention, 1 is a CPU, 3 is a keyboard control unit, 5 is a CRT control unit, 7 is an external storage device control unit,
8 is a built-in floppy disk device, 10 is a built-in hard disk device, 12 is RAM, 13 is ROM, 14 is an address storage unit, 15 is a calling unit, 26 is a switching unit, 2
7 is an attribute storage unit, 28 is an access control unit, 2, 16-2
Reference numerals 5 and 29 to 31 are bus lines for exchanging data and commands between the respective devices. Further, as a peripheral device connected to the information processing device 50, 4 is a keyboard,
6 is a CRT, 9 is an additional floppy disk device, and 11 is an additional hard disk device.

Here, the address storage unit 14 and the attribute storage unit 2
7 may be inside the RAM 12, and the calling unit 15
May be realized as an instruction (instruction) of the CPU 1 or as a program stored in the RAM 12 or the ROM 13, and the switching unit 26 and the access control unit 28 may be realized as a program stored in the RAM 12 or the ROM 13. .. The information processing device 50 does not necessarily have to include the built-in floppy disk device 8 and the built-in hard disk device 10.

First, before the switching unit 26 operates,
That is, the operation when the address of the external storage device control unit 7 is stored as the initial value in the address storage unit 14 will be described.

Access (reading, writing, or initialization of data) to the built-in floppy disk device 8, the expanded floppy disk device 9, the built-in hard disk device 10, and the expanded hard disk device 11, which are external storage devices.
To do so, data and instructions such as a unit number, a cylinder number, a sector number, a data length, a buffer address of read or write data for distinguishing a plurality of external storage devices are set, and the calling unit 15 is executed. The calling unit 15 executes the external storage device control unit 7 (stored as an initial value) according to the address stored in the address storage unit 14. The external storage device control unit 7 controls the designated external storage device in accordance with the data and instructions,
Reads, writes, or initializes data.

This operation is no different from the access to the external storage device in FIG. 6 showing the block configuration of the conventional information processing apparatus. That is, before the switching unit 26 operates, any access to the external storage device is transmitted to the external storage device control unit 7 without being restricted.

Next, the operation of the switching unit 26 and the operation relating to the external storage device access after the operation of the switching unit 26 will be described.

The timing at which the switching unit 26 operates is, for example, when the switching unit 26, the attribute storage unit 27, and the access control unit 28 are realized by software and loaded into the RAM 12 and then the switching unit 26 is called. Further, the switching unit 26, the attribute storage unit 27, and the access control unit 28 are stored in the RAM 12 or the ROM 13, and the switching unit 26 may be called by another software stored in the RAM 12 or the ROM 13.

When the switching unit 26 is called, the switching unit 26 replaces the address of the external storage device control unit 7 stored in the address storage unit 14 with the address of the access control unit 28.

After the operation of the switching unit 26, the internal floppy disk device 8, the additional floppy disk device 9, the internal hard disk device 10, and the additional hard disk device 11, which are external storage devices, are accessed (data reading,
(Writing or initialization) takes the operation described below. That is, data and instructions such as a unit number, a cylinder number, a sector number, a data length, a buffer address of read or write data for distinguishing a plurality of external storage devices are set, and the calling unit 15 is executed.
The calling unit 15 executes the access control unit 28 (result of the action of the switching unit 26) according to the address stored in the address storage unit 14. According to the attribute data stored in the attribute storage unit 27, the access control unit 28 outputs data and instructions such as a unit number, a cylinder number, a sector number, a data length, a read or write data buffer address, which are requested to be accessed, to an external device. It is determined whether or not to notify the storage device control unit 7, and if it is notified, the external storage device control unit 7 is executed. The external storage device controller 7 controls a specified external storage device in accordance with the transmitted data or command to read, write, or initialize data.

Next, the access control unit 28 will be described in detail with reference to FIG. FIG. 2 is a flowchart showing the processing of the access control unit 28. Reference numeral 100 is a processing start point, 199 is a processing end point, and 101 to 124 are processing steps.

The access control unit 28 determines from the unit number of the access request whether the unit is a built-in or expanded floppy disk device or a built-in or expanded hard disk device (101).
If the unit to be accessed is a built-in or additional hard disk device, it is determined whether the access request command is initialization, reading, or writing (102). If the instruction of the access request is read, the address to the attribute table for reading the unit number of the access target is obtained (107). This attribute table is stored in the attribute storage unit 27 of FIG. The cylinder number, sector number, and data length for which an access request has been made are collated with the attribute table (108), and as a result, it is determined whether the access request is permitted or prohibited (109).

As a result of the judgment (109), necessary error processing is performed when the access request is prohibited (110).

When the access request is permitted as a result of the determination (109), data or instruction such as a designated unit number, cylinder number, sector number, data length, buffer address of read or write data, etc. is used as an external argument. The storage device controller 7 is called (124).

In this way, the access control unit 28
Permit or prohibit reading from the built-in or additional hard disk drive.

The access control unit 28 performs the same processing,
Permits or prohibits the initialization and writing of the built-in or expansion hard disk drive and the initialization, reading, and writing of the built-in or expansion floppy disk drive.

Next, the processing (108) of collating the cylinder number, the sector number, and the data length of the access request with the attribute table will be described in more detail with reference to FIGS. 3 and 4. FIG. 3 is a flowchart of the attribute matching process (108) in FIG. Reference numeral 200 is a processing start point, 299 is a processing end point, and 201 to 209 are processing steps. Combined symbol 210 indicates that processing continues to the position of combined symbol 211.

FIG. 4 is a block diagram of the attribute storage unit 27 shown in FIG.
It is a figure which shows the attribute table memorize | stored in FIG. 300
˜320 are the read attribute table 3000 for the unit number 0, the initialization attribute table 3010 for the unit number 0, the address to the write attribute table 3020 for the unit number 0, 330 is the address to the read attribute table for the unit number 1, 3
Reference numeral 40 is an address to the write attribute table for the unit number n.

The attribute table 3000 has a unit number 0.
In the external storage device of No. 2, the start logical sector number and the end logical sector number are set as a set, and a structure is stored for every read prohibited area of the external storage device of unit number 0. Further, the nth start logical sector number Sn on the attribute table and n
It is arranged such that Sn <Sm (m = n + 1) holds between the first logical sector number Sm (m = n + 1). Further, in order to indicate the end of the table, "0FF" is added at the end of the attribute table 3000.
FFH, 0FFFFH "is added.

The attribute tables 3100 and 3200 have the same structure.

In the attribute table 3000, 3001
~ 3007 is the start logical sector number, 3011 to 3017
Is the ending logical sector number.

In the attribute table 3100, 310
1, 3102 is the start logical sector number, 3111, 311
2 is the end logical sector number.

In the attribute table 3200, 320
1,3202 is the start logical sector number, 3211,321
2 is the end logical sector number.

The attribute matching process (108) is called with the cylinder number, the head number, the sector number for which the access request is made, and the address to the attribute table as arguments.

First, an access (read or write) start logical sector number (logical address) X and an access end logical sector number Y are calculated from the cylinder number, head number, sector number, and data length for which an access request has been issued. Yes (201). The logical sector number can be uniquely obtained from the following formula.

(Logical address) = (H × CN + HN) × S + SN Where, H: number of heads (constant determined for each unit) S: number of sectors (constant determined for each unit) CN: cylinder number HN: head number SN: Sector number Next, 0 is substituted for the index i for searching the attribute table and initialized (202). I in the attribute table
It is checked whether the starting logical sector number Si of the th access prohibited area is "0FFFFH" (203). if,
If it is "0FFFFH", it means the end of the table, and therefore access permission is set in the determination result flag via the coupling symbols 210 and 211 (209). If the i-th access prohibited area start logical sector number Si is not "0FFFFH", Si is compared with the access start logical sector number X (205). If Si and X are equal as a result of the comparison, the determination result flag is set to prohibit (208), and if X is larger than Si, the index i is incremented by 1 (204) and the process returns to step 203 again. If X is smaller than Si, the (i-1) th access prohibited area end logical sector number Ej (j = i-1) and the access start logical sector number X
And are compared (206). If the comparison result Ej is greater than or equal to X, access prohibition is set in the determination result flag (208), and if Ej is less than X, the i-th access-prohibited area start logical sector number Si and access end logical sector number of the i-th attribute table are set. Compare with Y (20
7). If the comparison result Si is smaller than or equal to Y, access prohibition is set in the determination result flag (208), and Si is set.
If is larger than Y, access permission is set in the determination result flag (209). By the above processing, access permission or access prohibition is set in the determination result flag, and the determination result flag is returned as a return value to the caller of the attribute matching 108 (299).

In this embodiment, the information processing apparatus has been described in which the storage unit is the sector unit. However, even if the storage unit is the track unit or the cylinder unit, the access is prohibited or permitted similarly. Can be controlled.

If the access-prohibited area start logical sector number and the access-prohibited area end logical sector number at the beginning of the attribute table are stored as the first logical sector number and the last logical sector number in the access target unit, respectively, Access to the entire unit is prohibited,
Even if the information processing apparatus is characterized in that the storage unit is a unit, access prohibition or permission can be controlled. That is, access prohibition or permission can be controlled for each external storage device connected to the information processing device.

(Embodiment 2) FIG. 5 is a block diagram showing the configuration of (Embodiment 2) of the present invention in which basic peripheral devices are connected. 5, the attribute specifying unit 32 and the bus 33 shown in FIG.
It is configured to add and.

The attribute designating section 32 follows the attribute storage section 27 according to the input from the keyboard 4 or the attribute designating data read from the external storage device 8, 9, 10 or 11.
Change the attribute table stored in.

The attribute designation data includes the type of access (read, write, or initialization), the unit number, the logical sector (track or cylinder) numbers Si and Ei indicating the start and end of the designated area, and the designated area. It is composed of information on whether to prohibit or allow the access. Alternatively, a part of the attribute designation data may be fixedly determined in advance.

The attribute designating section 32 changes the attribute table,
One or more sets of access prohibited area start logical sector number Si and access prohibited area end logical sector number Ei are added or deleted, or access prohibited area start logical sector number or access prohibited area end logical sector number is separated. It is performed by combining the operation of rewriting to the value of. As a result, the area for which access is permitted or prohibited can be changed to a storage unit.

[0043]

According to the present invention, access (reading, writing, or initialization) is prohibited in a storage unit (sector) for a general external storage device that does not give special consideration to confidentiality of stored contents and data protection. , Tracks, cylinders, or units) can be set freely to protect confidentiality of stored contents and data protection in areas where access is prohibited, and to effectively use the resources of the storage medium that corresponds to areas where access is allowed. can do.

Especially when a plurality of operators use one information processing apparatus, the accessible area can be determined for each operator by the present invention, so that data protection and confidentiality can be surely achieved. ..

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an information processing device to which a basic peripheral device of the present invention is connected.

FIG. 2 is a flowchart showing processing of an access control unit of the present invention.

FIG. 3 is a flowchart of attribute matching processing of the present invention.

FIG. 4 is a diagram showing an attribute table stored in an attribute storage unit of the present invention.

FIG. 5 is a block diagram showing a configuration of a second embodiment in which a basic peripheral device of the present invention is connected.

FIG. 6 is a block diagram showing a configuration of a conventional information processing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... CPU 3 ... Keyboard control part 4 ... Keyboard 5 ... CRT control part 6 ... CRT 7 ... External storage device control part 8 ... Internal floppy disk device 9 ... Additional floppy disk device 10 ... Internal hard disk device 11 ... Additional hard disk device 12 ... RAM 13 ... ROM 14 ... Address storage unit 15 ... Calling unit 26 ... Switching unit 27 ... Attribute storage unit 28 ... Access control unit 2, 16-25, 29-31 ... Bus line

Claims (9)

[Claims] 1. An external storage device control means for sending an instruction to an external storage device to control the external storage device, an address storage means for storing an address of the external storage device control means, and the external device according to information of the address storage means. In an information processing device including a calling unit for calling the storage device control unit, an attribute storage unit that stores a read attribute indicating whether reading is permitted or prohibited for each storage unit,
According to the read attribute stored by the attribute storage means,
An access control unit for permitting or prohibiting reading for each storage unit; and a switching unit for changing the content of the address storage unit and switching the call of the external storage device control unit to the call of the access control unit. A method for controlling an external storage device, comprising controlling reading from the external storage device. 2. An external storage device control means for sending an instruction to an external storage device to control the external storage device, an address storage means for storing an address of the external storage device control means, and the external device according to information of the address storage means. In an information processing device including a calling unit for calling the storage device control unit, an attribute storage unit that stores a writing attribute indicating whether writing is permitted or prohibited for each storage unit,
According to the write attribute stored in the attribute storage means,
An access control unit that permits or prohibits writing for each storage unit; and a switching unit that changes the content of the address storage unit and switches the call of the external storage device control unit to the call of the access control unit. A method for controlling an external storage device, comprising controlling writing to the external storage device. 3. An external storage device control means for sending an instruction to the external storage device to control the external storage device, an address storage means for storing an address of the external storage device control means, and the external device according to the information of the address storage means. In an information processing apparatus including a calling unit for calling a storage device control unit, an attribute storage unit that stores an initialization attribute indicating whether initialization is permitted or prohibited for each storage unit, and the attribute storage unit stores the attribute. According to the attribute of the initialization, the access control means for permitting or prohibiting the initialization for each storage unit and the contents of the address storage means are changed to switch the call of the external storage device control means to the call of the access control means. A method for controlling an external storage device, comprising: switching means for controlling initialization of the external storage device. 4. The method for controlling an external storage device according to claim 1, wherein the storage unit is a sector unit. 5. The method of controlling an external storage device according to claim 1, wherein the storage unit is a track unit. 6. The method of controlling an external storage device according to claim 1, wherein the storage unit is a cylinder unit. 7. The method of controlling an external storage device according to claim 1, wherein the storage unit is a unit. 8. A method for controlling an external storage device according to claim 1, further comprising attribute designation means for designating addition or deletion of information stored in said attribute storage means. 9. An information processing apparatus using the method for controlling an external storage device according to any one of claims 1 to 8.