JP2004287553A - Data display method for recording medium, computer program, and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily confirm data in a recording medium completely erased by a data erasing program. <P>SOLUTION: A dump screen 500 displays HD No.501, size 502 and sector No.503 dumped at present, an address display part 504 displaying addresses of areas dumped at present, a binary display part 505 displaying binary data recorded in the respective addresses, in hexadecimals, and a text display part 506 making a text display of the binary data recorded in the respective address, according to character codes such as ASCII. The dump screen displays data for a 1/2 sector, and a dump range can be moved in the unit of 1 sector or 1/2 sector by prescribed key operation. Further, a shift to a retrieval mode can be made by prescribed key operation to start specific data retrieval such as retrieval of data other than (00)<SB>h</SB>. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for displaying data in a recording medium, and more particularly, to a method for displaying data in a recording medium, a computer program, and a recording medium that allow easy confirmation of data in a recording medium such as a hard disk.
[0002]
[Prior art]
For the purpose of preventing personal information and important data from leaking from the hard disk when returning a leased or rented personal computer (PC) or letting go of an old computer for replacement, etc. There are many means for erasing data, and there are various erasing methods.
[0003]
For example, in the NSA standard (U.S. Department of Defense NSA standard), complete erasure of recorded data is realized by writing a random number the first time and the second time and writing zero (hexadecimal 00) the third time. In the old NSA standard, complete erasure of recording data is realized by writing zero at the first and third times and writing a fixed value (for example, hexadecimal FF) at the second and fourth times. Further, in the DoD standard (U.S. Department of Defense standard), complete erasure of recorded data is realized by writing zero at the first time, fixed value at the second time, and random number at the third time. In the NATO standard (NATO standard), complete erasure is realized by writing zero at the first, third, and fifth times, writing a fixed value at the second, fourth, and sixth times, and writing a random number at the seventh time. ing.
[0004]
In addition, in order to prevent unauthorized use of application software that executes the above-described erasing method, a method of writing specific information of the used application software to a start address or an end address of the hard disk after data erasing processing on the hard disk is also known. (See Patent Document 1). According to this method, it is possible to specify the application software from which the data on the hard disk has been deleted. Further, by including the serial number of each application software in the specific information, each application software can be specified.
[0005]
There is also known a method for achieving high-speed data erasing (see Patent Document 2). According to this method, random unit data is created, and the recording data for erasing is created by repeatedly using the random unit data. Therefore, the time for creating the recording data for erasing can be shortened, and the time for the data erasing process can be shortened. .
[0006]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2002-312128 [Patent Document 2]
JP 2003-030801 A
[Problems to be solved by the invention]
However, even if the data in the hard disk is erased using these erasing methods, there is no change at first glance except for a change such as not being able to start after erasing, so the data in the hard disk is securely erased. There is a problem that you do not know whether. In many cases, a PC recycler or the like requires a means of investigation or certification, and therefore, means for easily confirming the erased state is desired.
[0008]
It is also possible that data in the hard disk is not completely erased over the entire recording area. In other words, although the first half of the recording area has been erased well, the latter half may not be erased for some reason and the data may remain as it is. Therefore, the data may be completely erased. It is necessary to have a means for confirming whether or not it has occurred.
[0009]
Accordingly, it is an object of the present invention to provide a data display method, a computer program, and a recording medium in a recording medium, which can easily confirm data in a recording medium such as a hard disk.
[0010]
[Means for Solving the Problems]
The object of the present invention is characterized in that it has a step of dumping and displaying data in a recording medium, a step of searching for predetermined data from the recording medium, and a step of displaying the search result on the dump display. This is achieved by a data display method of a recording medium.
[0011]
According to the present invention, it is possible to easily confirm whether or not data erasure of a recording medium has been correctly executed.
[0012]
In a preferred embodiment of the present invention, the predetermined data is any of binary data, text data, data other than “0”, data other than “1”, or an exceptional value of a random number pattern.
[0013]
According to the preferred embodiment of the present invention, it is possible to execute a suitable search for confirming whether or not the data erasure of the recording medium has been securely performed.
[0014]
In a further preferred embodiment of the present invention, prior to the step of searching for the predetermined data, arbitrary binary data, arbitrary text data, data other than “0”, data other than “1”, or random number pattern A step of selecting one of options including any two or more of the exceptional values; and a step of setting the predetermined data according to the selection result.
[0015]
According to a further preferred embodiment of the present invention, it is possible to provide various search methods corresponding to the data erasing method, and perform a search suitable for confirming whether data erasure of the recording medium has been securely performed. Can be performed.
[0016]
In a further preferred embodiment of the present invention, the step of displaying the dump includes a step of displaying the data in the recording medium in units of one-half sector, and a step of displaying the dump in units of one-sector or one-half sector. Including the step of switching.
[0017]
According to a preferred embodiment of the present invention, the entire dump screen can be reliably displayed even in the VGA display, and a data erasing method for writing specific information at a predetermined position (for example, first and last) of each sector. In the case of the deletion, the specific information can be always displayed on the dump screen, and it is easy to confirm the proof that the deletion has been performed.
[0018]
The object of the present invention also includes a step of dumping and displaying data in a recording medium, a step of searching for predetermined data from the recording medium, and a step of: The present invention is also achieved by a computer program for executing a displaying step on a dump display.
[0019]
The above object of the present invention is also achieved by a computer-readable recording medium recording the computer program.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0021]
FIG. 1 is a schematic block diagram showing the configuration of a computer system that implements a method for erasing data from a hard disk and displaying the data according to a preferred embodiment of the present invention.
[0022]
As shown in FIG. 1, the computer system 100 includes a computer main body 101, display means such as a display 102, and data input means such as a keyboard 103 and a mouse 104. These display means and data input means constitute a graphical user interface together with a data erasing program for a hard disk described later. A computer main body (sometimes simply called a computer) 101 is a configuration of a general personal computer, and includes a CPU 105, a memory 106, a hard disk drive (HDD) 107, a flexible disk drive (FDD) 108, and a CD-ROM drive 109. , An input / output interface (I / O) 110 and the like.
[0023]
In the present embodiment, the hard disk drive 107 is a target of data erasure, and the hard disk drive 107 includes a hard disk (HD). Only one hard disk drive 107 may be connected, or a plurality of hard disk drives 107 may be connected as shown. For example, in the case of IDE connection, up to four hard disk drives can be connected. On the other hand, the data erasing program 111 of the hard disk is provided in a state of being recorded on the flexible disk (FD) 108F or the CD-ROM 109C. The hard disk data erasing program 111 is read from an FDD or CD-ROM drive when the computer is started up, and is automatically expanded in the memory 106. As a result, the program operates at the BIOS level, and data is erased from the hard disk.
[0024]
FIG. 2 is a screen diagram showing a main screen of the data erasing program of the hard disk displayed on the display 102.
[0025]
As shown in FIG. 2, on the main screen 200, a menu box 201 for selecting any one of the items “data erase” 201a, “dump” 201b, and “end” 201c is displayed. Each item is selected by a predetermined key operation and shifts to each mode. The “data erasing” 201a is a mode for executing an erasing process according to the erasing method according to the present invention, and shifts to the mode when the “1” key is pressed. The "dump" 201b is a mode for checking the contents of the hard disk. When the "2" key is pressed, the mode shifts to that mode. The "end" 201c is a mode for ending the hard disk erasing program. When the “data erase” 201a is selected, it is preferable to execute a process of repeatedly confirming whether the erase process may be executed before actually executing the erase process. Next, the procedure of the data erasing process will be described in detail.
[0026]
FIG. 3 is a flowchart showing the procedure of the data erasing process of the hard disk.
[0027]
As shown in FIG. 3, in this data erasing process, first, a random number value is written in the entire erasure target area of the hard disk (S301). The random number value need not be generated in units of bits, and may be generated in units of several bits or several bytes. Further, a predetermined random number pattern may be repeatedly used.
[0028]
Next, specific information is written in a predetermined position of each sector, and a constant value of "0" or "1" is written in other areas (S302 to S304). Specifically, in this example, specific information is written as binary data from the beginning of the sector (S302). Next, a constant value of "0" or "1" is written until just before leaving an area for recording specific information (S303). Then, by writing specific information again as binary data at the end of the sector (S304), writing for one sector is completed. That is, in this example, specific information is written at the first and last positions of each sector, and a constant value of "0" or "1" is written at other positions. A sector is a unit for reading / writing data from / to a magnetic disk such as a flexible disk or a hard disk, and one sector is 512 bytes. When the writing of one sector is completed, it is determined whether or not the writing of the entire erasure target area has been completed (S305). When the processing is completed (S304Y), the erasing process is terminated. According to this erasing method, the number of times of writing to the hard disk is two.
[0029]
Since the specific information is the only proof that the erasure has been performed, the name of the program provider or the name of the program (application software) that certifies that the data erasure program has been executed without fail, It is preferable to write the date and time when the erasing is executed, but the present invention is not limited to these. For example, different information such as a serial number may be written for each sector, and arbitrary information specified by the user may be recorded. Therefore, a character code such as ASCII is used for the specific information.
[0030]
FIG. 4 is a data map showing an example of the recorded contents of the hard disk erased by the above-mentioned erasing method.
[0031]
As shown in FIG. 4, in the present embodiment, character information 402 of "TDK200330311930001" is recorded at the beginning and end of each sector 401 of the hard disk, and a constant value is recorded in other areas. In FIG. 4, the area where the constant value is recorded is shown as blank. The actual character information is recorded as binary data. Here, the portion of “200303019” in the character information 402 is the date (March 19, 2003) at which the erasing process was executed, and the portion of “123001” is the time (12:30:30). Yes, it is set according to the time information in the computer. As described above, if specific information is recorded in each sector, it can be confirmed in all sectors.
[0032]
FIG. 5 is a diagram showing a dump screen displayed when a dump is selected on the main screen 200 shown in FIG.
[0033]
As shown in FIG. 5, on the dump screen 500, a hard disk (HD) number 501, a capacity (size) 502, and a sector number 503 that are currently being dumped are displayed. When a plurality of hard disks are connected to the computer, each can be distinguished by the HD number 501. The hard disk to be dumped can be switched by key operation. The sector number 503 is the number of the sector currently being dumped, and will be referred to when changing the sector to be dumped, as will be described later in detail.
[0034]
Further, an address display unit 504, a binary display unit 505, and a text display unit 506 are displayed on the dump screen 500. The address display section 504 displays the address of the area currently being dumped. The binary display unit 505 displays binary data recorded at each address in hexadecimal (HEX). In the text display unit 506, binary data recorded at each address is displayed as text according to a character code such as ASCII. Therefore, when the data on the hard disk is erased by the erasing method shown in FIG. 2, specific information is displayed on the text display unit 506 as text. In this specification, a hexadecimal number may be represented by (xx) _h (x is any one of 0 to 9 and A to F).
[0035]
On the dump screen 500, data for one half sector is displayed. That is, 256 bytes of data can be displayed in one screen. The dump range can be moved in one-sector units or one-half-sector units by a predetermined key operation, or can be dumped by specifying a sector number. As described above, this data erasing program operates at the BIOS level, but the VGA mode (640 dots × 480 dots) is adopted for the display at the BIOS level. Therefore, in the case of the VGA mode, it is difficult to display all data of one sector (512 bytes). However, if the data is 256 bytes, it can be displayed reliably. In the present embodiment, since the first half of the sector in the hard disk erased by the erasing method shown in FIG. 2 is displayed as a dump, specific information is recorded at the head of the sector. For this reason, specific information is shown in the text display unit 506 as text data (TDK20033031293001).
[0036]
As described above, according to the present embodiment, when erasing a hard disk, specific information is recorded at the beginning and end of each sector of the hard disk. Can be confirmed.
[0037]
Further, according to the present embodiment, since the dump is displayed in units of one-half sector, the entire dump screen can be reliably displayed even in the VGA display. In addition, since the dump is displayed in units of one-half sector and the dump is switched in units of one sector or one-half sector, specific information is written at the beginning and end of one sector, as shown in FIG. In the case of the deletion, the specific information can be always displayed on the dump screen, and it is easy to confirm the proof that the deletion has been performed.
[0038]
In order to confirm whether or not the erasing process has been correctly performed on the entire erasing area on the above-described dump screen, a search for specific data may be performed. This search is started by performing a predetermined key operation such as pressing an “F” key on a keyboard, for example. This causes a transition to the search mode, in which a menu box for search is displayed.
[0039]
FIG. 6 is a diagram illustrating a search menu box.
[0040]
As shown in FIG. 6, various search methods are displayed in the search menu box 600. In the present embodiment, “search by numerical value (HEX) data” 601, “search by character (ASCII) data” 602, “search by data other than 00” 603, “search by data other than FF” 604, “random number” Pattern Exception Search ”605 and the like are provided. When one of these is selected by a predetermined key operation and the search is executed, the search is started from the sector currently displayed on the screen. However, when the “search by numerical value (HEX) data” 601 is selected, the search is started after the input of the hexadecimal value (HEX) is requested, and the “search by character string (ASCII)” 602 is selected. In this case, the search is started after input of text data (ASCII) is requested.
[0041]
FIG. 7 is a diagram showing an example of a dump screen of a hard disk deleted by a predetermined deletion method.
[0042]
As shown in FIG. 7, according to the dump screen 700, it is estimated that the erasing process is executed by the erasing method in which (00) _h is recorded by the last overwriting in the erasing process for each address. You. That is, it can be estimated that data has been erased by writing "0" data to the entire hard disk. Therefore, by executing “search for data other than 00” 603, it is possible to confirm whether the entire disk has been securely erased by overwriting the “0” data. When "Search for data other than 00" 603 is selected in the search menu box 600, the search is executed, and when data (701 ( _h ) in this case) other than (00) _h is found, the address of the address is searched. The value is highlighted. Therefore, the user can easily confirm whether or not all data has been rewritten to "0" data.
[0043]
FIG. 8 is a diagram showing another example of the hard disk dump screen.
[0044]
As shown in FIG. 8, according to the dump screen 800, it is estimated that the erasing process is executed by the erasing method in which (FF) _h is recorded by the last overwriting in the erasing process for each address. Is done. That is, it can be estimated that the data has been erased by writing "1" data to the entire hard disk. Therefore, by executing “search for data other than FF” 604, it is possible to confirm whether or not the entire disk has been completely erased by overwriting the “1” data. When "search for data other than FF" 604 is selected in the search menu box 600, the search is executed, and if data (here, (00) _h ) 801 other than (FF) _h is found, the value of the address is found. Is highlighted. Therefore, the user can easily confirm whether or not all data has been rewritten to "1" data.
[0045]
FIG. 9 is a view showing still another example of the dump screen of the hard disk.
[0046]
As shown in FIG. 9, according to the dump screen 900, although a specific value is recorded, it is unknown which data is erased by which method. However, if it is known that the data has been erased by a random number using the erasing method such as the DoD standard, or if there is a possibility, the random number pattern is found and it is checked whether the entire disk has been erased with the random number. can do. When "exception search of random number pattern" 605 is selected in the search menu box 600, the search is executed, and when data different from the regular random number pattern is found, the value of the address is highlighted.
[0047]
In “exception search of random number pattern” 605, the random number patterns are found one after another, and a search for a certain number of consecutive patterns is made until the end. For example, as shown in the figure, first, it is detected that the pattern 901 of (62, 6A) _h is repeated, it is recognized that it is a random number pattern, and the search is continued until a different pattern appears. Next, a new pattern 902 of (FD, 6F) _h is found. In this case, the search is continued while confirming that the same pattern is repeated. Thereafter, even when a pattern 903 of (84, 2A) _h is newly found, the search is advanced while confirming that the same pattern is repeated. If another (10, 3E) _h pattern 904 is found while the (84, 2A) _h pattern 903 is being repeated, the address value is highlighted. Therefore, the user can easily confirm whether or not all the data has been rewritten to the random number pattern.
[0048]
FIG. 10 is a flowchart showing a procedure from the dump display to the search.
[0049]
As shown in FIG. 10, first, in the dump display, data in the recording medium is dumped in units of a half sector, and the dump result is displayed on the screen (S11). At this time, the dump display is switched in units of one sector or in units of one-half sector by a key operation. When a search mode is selected by a predetermined key operation in the dump display state (S12Y), a search menu box is displayed, and arbitrary binary data, arbitrary text data, data other than "0", and data other than "1" A list of search methods such as the data of the data or the exception value of the random number pattern is displayed (S13). When one of these options is selected (S14Y), a data search process according to that method is executed (S15), and the search result is displayed on the dump screen (S16). If the search is to be continued further (S17Y), the search is performed again from the subsequent address (S15, S16), and if not, the search is terminated (S17N).
[0050]
As described above, according to the present embodiment, “non-zero search” is prepared for “0” data, that is, a hard disk that is likely to be erased at (00) _h , and “1” data, That is, since "search other than FF" is prepared for the hard disk erased in (FF) _h , it can be easily confirmed whether or not the hard disk has been erased correctly. Furthermore, assuming that the numerical value changes in a certain pattern even for hard disks that are likely to be erased by random numbers, first confirm that the searched pattern is continuous for a certain number of After finishing, check the continuous state of the next pattern in the same way, and if there is an irregular part, determine that the part may not be correctly erased and provide a function to highlight that part Then, it can be easily confirmed whether or not the data has been correctly erased.
[0051]
The present invention is not limited to the above embodiments, and various changes can be made within the scope of the invention described in the claims, and these are also included in the scope of the present invention. Needless to say, there is.
[0052]
For example, in the above embodiment, the case where data in the hard disk is confirmed has been described as an example. However, the present invention is not limited to this. For example, a flexible disk (FD), a magneto-optical disk (MO), a flash memory card And various types of recording media such as USB memory. However, for a recording medium without the concept of a sector, 512 bytes correspond to one sector.
[0053]
Further, in the above-described embodiment, the case where specific character information is recorded at the beginning and end of each sector of the hard disk and a constant value is recorded in other areas is described as an example. However, the present invention is not limited to this. Instead, it is sufficient that specific information is recorded once per half sector. Further, if specific information is recorded at a predetermined position of each sector of the hard disk, where in the sector the specific information is recorded It does not matter.
[0054]
Further, in the above embodiment, the case where the data erasing program includes the data display program for realizing the dump function and the search function has been described as an example. However, the present invention is not limited to this. May be independently provided as separate programs.
[0055]
【The invention's effect】
As described above, according to the present invention, data in a recording medium such as a hard disk is displayed on a display in a form that can be visually recognized such as binary data or text data. Since the pattern search is supported, the data in the recording medium can be easily checked.
[Brief description of the drawings]
FIG. 1 is a schematic block diagram showing a configuration of a computer system that implements a method for erasing data from a hard disk and displaying the data according to a preferred embodiment of the present invention.
FIG. 2 is a screen diagram showing a main screen of a data erasing program of a hard disk displayed on a display 102;
FIG. 3 is a flowchart illustrating a procedure of a data erasing process of a hard disk;
FIG. 4 is a data map showing an example of recorded contents of a hard disk erased by the above-mentioned erasing method.
FIG. 5 is a diagram showing a dump screen displayed when a dump is selected on the main screen 200 shown in FIG. 2;
FIG. 6 is a diagram illustrating a search menu box.
FIG. 7 is a diagram illustrating an example of a dump screen of a hard disk deleted by a predetermined deletion method.
FIG. 8 is a diagram showing another example of a hard disk dump screen.
FIG. 9 is a diagram showing still another example of the dump screen of the hard disk.
FIG. 10 is a flowchart illustrating a procedure from a dump display to a search.
[Explanation of symbols]
REFERENCE SIGNS LIST 100 computer system 101 computer main body 102 display 103 keyboard 104 mouse 106 memory 107 hard disk drive (HDD)
108 Flexible Disk Drive (FDD)
108F Flexible disk (FD)
109 CD-ROM drive 109C CD-ROM
110 input / output interface (I / O)
111 Data Erase Program 200 Main Screen 201 Menu Box 201a "Erase Data" Item 201b "Dump" Item 201c "End" Item 401 Each Sector 402 Character Information (TDK200303319123001)
500 Dump screen 501 Hard disk (HD) number 502 HD capacity (size)
503 Sector number 504 Address display section 505 Binary display section 506 Text display section 600 Menu box for search 601 "Search by numerical value (HEX) data"
602 "Search by character (ASCII) data"
603 "Search for data other than 00"
604 "Search for data other than FF"
605 "Exception search of random number pattern"
700 Example of dump screen 701 Data other than (00) _h (here (10) _h )
800 Other example of dump screen 801 (FF) Data other than _h (here (00) _h )
900 Still another example of a dump screen 901 (62, 6A) _h pattern 902 (FD, 6F) _h pattern 903 (84, 2A) _h pattern 904 (10, 3E) _h pattern

Claims (6)

A step of dumping and displaying data in the recording medium;
Retrieving predetermined data from the recording medium;
Displaying the search result on the dump display. The predetermined data is:
2. The data display method for a recording medium according to claim 1, wherein the data is one of binary data, text data, data other than "0", data other than "1", and an exceptional value of a random number pattern. Prior to the step of searching for the predetermined data,
Selecting one of options including any two or more of arbitrary binary data, arbitrary text data, data other than “0”, data other than “1”, and an exceptional value of a random number pattern;
2. The data display method for a recording medium according to claim 1, further comprising the step of setting the predetermined data according to the selection result. The step of displaying a dump includes:
A step of dumping and displaying data in the recording medium in units of a half sector;
4. The data display method for a recording medium according to claim 1, further comprising a step of switching the dump display on a one-sector basis or a half-sector basis. A computer equipped with a recording / reproducing means for recording media,
A step of dumping and displaying data in the recording medium;
Retrieving predetermined data from the recording medium;
A computer program for executing a step of displaying the search result on the dump display. A computer-readable recording medium on which the computer program according to claim 5 is recorded.

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