JPH01253051A - Information protecting method - Google Patents

Abstract

PURPOSE:To disable a third party to use information even if obtaining a decoding means by adding selection information for specifying next information for a necessary piece of divided information and decoding them by a desired decoding means. CONSTITUTION:A program is divided into a necessary number of parts, and selection information for specifying partial programs to be executed next are added to the divided programs, decoded by a desired decoding means, and written and stored on a floppy disk. Then when the program or data is used, the desired decoding means is connected to a specific transfer part to enable the execution of the program or access to the data. Consequently, the third party who only obtains the decoding means is prevented from using the data illegally and the information is protected.

Description

[Detailed Description of the Invention] (Field to which the invention pertains) The present invention relates to an information protection method, particularly a method for encrypting a program or data by a desired encryption means and allowing only an authorized user to decrypt the encrypted program or data. information protection methods that can be used.

(Prior Art) Currently, it is common practice to write and save programs or data essential to operating a converter on a storage medium such as a USB disk, and then read and use them when necessary. Since programs or data written to a FP7 disk can easily be transferred to another FP7 disk, there is a risk that the program or data may be stolen by a third party.

Conventionally, a method to prevent theft of information by a third party and protect information 9, such as program information, is to encrypt the program using a desired encryption method, then write and save it on a floppy disk, and then use it when using it. Insert a ROM cartridge in which a decryption program created based on a decryption method corresponding to the program encryption method is written into the ROM cartridge slot of the converter, and use the decryption program to decrypt the encrypted program and use it. There is a method.

According to this method, even if a third party illegally copies a program stored on a floppy disk to another floppy disk, the encrypted program will be copied to this floppy disk. Since it is difficult to obtain the original program from the disk, the program can be protected from plagiarism.

However, with this method, if a third party obtains a ROM cartridge corresponding to the encrypted program and inserts it into the ROM cartridge slot, the encrypted program on the floppy disk can be easily executed. had to be kept in.

(Object of the Invention) The present invention has been made in view of the above-mentioned circumstances, and even if a third party obtains No. 1 means such as a ROM cartridge, it is not possible to use information such as encrypted programs or data. The purpose is to provide information protection methods that are difficult to protect.

(Summary of the Invention) In order to achieve the above-mentioned object, the information protection method of the present invention, for example, divides a program into a required number of programs and adds selection information for specifying the next divided program to be executed to each divided program. At the same time, each of these is encrypted by a desired encryption means, and the encrypted divided programs are arranged in the order of program execution and written to a floppy disk for storage.

In addition, when using this encrypted program, it is necessary to selectively connect the decryption means corresponding to the encryption means of each encrypted divided program to the predetermined transfer section, so that each divided program can be Specifying a transfer unit according to selection information and using a finger (Example) The present invention will be described in detail below based on an example shown in the drawings.

FIG. 1 is a flowchart showing an embodiment of the encryption means according to the present invention.

First, a program to be protected is written into a memory, the number of divisions of the program is input from the keyboard, and the program to be protected is divided by memory address according to the input number to obtain the input number of divided programs.

Next, from the keyboard, the user selects the type of encryption means for each of the nine divided programs and inputs information specifying the decryption means corresponding to each encryption means.

Each division program is based on this key human power.

It is determined whether there is a divided program to be executed next in the order of execution, that is, it is determined whether the divided program is to be executed last. Based on this judgment, if there is a divided program to be executed in the 9th time, selection information specifying the decryption method of the divided program to be executed in the 1st time is added to that divided program, and this is encrypted by the encryption method selected at the time of key manual operation. do. In addition, in the case of a divided program to be executed last, the divided program is encrypted by the encryption means selected at the time of key input. Following these steps, the encrypted divided programs are recorded from memory and stored on a floppy disk in the order of their execution.

Next, the case of decrypting an encrypted program will be explained.

In the case of decoding, a transfer section of AO to An that selectively connects the decoding means DI and D2 for decoding based on the encrypted program as shown in FIG. 2 is provided in advance, and each divided program is selected. An expansion device 1 is provided which selects a predetermined transfer section according to information.

To use this extension [1] and decrypt the encrypted program saved on the floppy disk as described above, the third
If you follow the steps on the p-chart (shown in the figure), you will be able to do it. First, the decryption means DI and D2 corresponding to the encryption means of each of the encrypted divided programs are respectively connected to the transfer section corresponding to the selection information of the divided program. Next, write from the file to the program memory saved as above,
From the keyboard, input the leading band of the encrypted divided program to be executed first and the corresponding selection information. After inputting the key, the encrypted divided program at the designated starting address is decrypted by the decryption means of the transfer unit according to the selection information 9, and the original divided program is written into the memory. then 1
The original division program determines whether this includes selection information. If selection information is included, the encrypted division program to be executed next is decrypted by the decryption means of the transfer unit according to the selection information in the same way as the procedure after manually inputting the key described above according to the information. The divided program is stored in memory, and 4 (1) judgments are made as to whether or not the apricot selection information is included. Also, if the 8 selection information is not included, the decoding procedure is terminated and the 1 element is Execute the divided programs in the order they were decrypted.

FIG. 4 is a configuration diagram showing an embodiment of a combinator system that operates according to the procedure described above.

In the figure, 2 is a CPU that performs arithmetic processing according to each program, 3 is a memory for storing programs or data, and 4 is an input/output device for transferring programs or data between the internal and external parts. These are connected to each other by seven dress lines, a cheater line, and a control line to form a combinator 5.

Furthermore, this combination gourd 5 has a CRT 61 key for displaying the screen according to the execution status of the program, a keyboard 7 for manual operation, a floppy disk drive 9 for accessing the floppy disk 8 for recording the program, and a boot program for encrypting the program. Written encrypted ROM1
0.11, and an expansion device 14 for connecting the decryption ROMs 12 and 13 containing the decryption program, and these devices and the input/output section 4 are connected by required lines. Configure a combinator system. Further, the expansion device 14 is constituted by transfer sections 15-O to 15-3 that selectively connect the decoding ROMs 12 and 13.

The combinator system described above operates as follows.

Here, the program P to be protected is divided into program P
Encrypted programs As and B are divided into three parts from 1 to P3 and boogrammed based on mutually different encryption methods.
S is written into encrypted ROMs 10 and 11, respectively. or,
Encryption program ASK corresponding decryption program AD
is transferred to the decrypted ROMI2 and transferred to the transfer unit 15-!
A case will be described in which a decryption program BD corresponding to the encrypted program BS is written in the decryption ROM 13, and this is connected to the transfer section 15-3.

When a program P is to be encrypted, a cryptographic program S programmed based on a p-chart (shown in FIG. 1) is loaded from the floppy disk 8 into the memory 3 and executed. This allows the CPU
2 loads the program P into the memory 3 and presses the keyboard 7.
Enter the number 3 to divide program P from
The address range of each of the divided programs P1 to P3 is determined so as to divide the memory area into three by measuring the internal pressure of the memory area read. Then, from the keyboard 7, select the encrypted ROM 10 for each of the divided programs P1 and P3, select the encrypted ROM II for the divided program P2, and transfer the decrypted ROMs 12 and 13 to the transfer units 15-1 and 15-3, respectively. Enter the information that corresponds to the connection.

Accordingly, the CPU 2 loads the designated encoding program As into the memory 3 and executes the transfer unit 15-3.
A cipher division program C1 is created by encrypting the division programming and selection information S1 by a predetermined encryption means, and this is written into a vacant area of the memory 3. Also, C
4. The PU2 writes the selection information S2 specifying the transfer unit 15-1 in an empty area of the memory 3. A code division program C which is executed after loading the encryption program BS from the encryption ROM II into the memory 3 and encrypting the 9-part program P2 and the selection information S2 by a predetermined encryption means.
2 and writes it into the next memory area of the cipher division program CI. Furthermore, CPU2 is an encrypted ROM
After loading the encrypted program As from l0 into the memory 3 and executing it, a cipher division program C3 is created by encrypting the 9-division program P3 by a predetermined encryption means, and this is stored in the memory area next to the cipher division program C2. Write.

The code-divided boograms C1 to C3 thus written in the memory area of the memory 3 are saved on the floppy disk 8 by operating the keyboard 7.

Next, a case will be described in which decryption is performed based on the program P encrypted as described above.

First, the decoding ROMs 12 and 13 are transferred to the transfer unit 15-1.
and 15-3, loads the decoding program D programmed from the floppy disk 8 into the memory 3 based on the flowchart shown in FIG. 3, and executes the decoding program D. As a result, CPU2
Load the cipher division programs C1 to C3 from the Faybee disk 8 into the memory 3, input the starting address of the cipher division program C1 to be executed first from the keyboard 7, and specify the corresponding transfer unit 15-1. By this, the decoding program A D '? is transferred from the decoding ROM 12 to the memory 3. :Write it, execute it, decrypt it based on the cipher division program c1, obtain the division program PI with the selection information S1 added, and remove the selection information s1 (・Place the division program P1 in an empty area of the memory 3. Next, the CPU 2 uses the selection information Sl to write the transfer unit 15-
3, writes the decrypted program BD from the decryption ROM 13 to the memory 3, executes it, decrypts it based on the cipher division program C2, obtains the division program P2 to which the selection information S2 is added, and removes the selection information S2. The divided program P2 is written in the memory area next to the divided program P1 excluding the above-described selected program 81. Furthermore, C
The PU2 specifies the transfer unit 15-1 by the selected program S2, writes the decryption program AD from the decryption ROM 12 to the memory 3, executes it, and executes the decryption program AD.
3 to obtain a divided program P3, which is loaded into the memory area K11F next to the divided program P2 excluding the selection information S2.

After decoding, the CPO 2 executes the divided program programs Pi to P3 in the memory 3.

Therefore, according to the method explained above, even if a third party obtains the decryption ROMs 12 and 13, if they are connected to a unit other than the transfer units 15-1 and 15-3, the cipher-divided program programs CI to C3 will be Decryption RO corresponding to each
Since the transfer unit to which M is connected cannot be specified, the original divided programs Pi to P3 cannot be obtained, that is, unauthorized use of program P can be prevented.

In the above embodiment, when encrypting a divided program, an encrypted ROM in which a desired encrypted program is written is used; however, the present invention is not limited to this. A ROM 16 into which an encryption program programmed based on a desired encryption method is written.A CPU 1 for executing an execution process according to the encryption program.
7. Write down the split program from the combiator tit f
It is also possible to use an encryption device 20 that includes a second RAM 18 and an input/output section 19 for connecting the computer to the computer. This is done by transferring the required divided program from the computer to the RAM 18, creating a corresponding code division program according to the encryption program in the ROM 16, writing it into the free memory area of the RAM 18, and writing the code division program to the RAM 18. This is to be transferred to the converter. According to this, it is not necessary to write the encryption program into the memory of the convoter, which is convenient in preventing the encryption means from being stolen by a third party. Further, the above-mentioned encryption device 20 writes a decrypted program programmed into the ROM 16 based on a desired decryption means, and connects it to a predetermined transfer unit to decrypt the program based on the encryption program. A decryption device that can do this would be convenient in preventing third parties from stealing the decryption means.

Further, in the above description, the expansion device is selectively connected to a decoding means such as a decoding ROM, but the present invention is not limited to this, and the present invention has a plurality of locations where the decoding means can be selectively connected, and the present invention is not limited to this. If it is specified according to the selection information, it is acceptable. For example, the decoding means may be selectively connected to the input/output section of the Humbi-Li, and the boat address of a predetermined input/output section may be designated in accordance with the selection information.

Furthermore, in the present invention, as described above, divided programs encrypted by a desired encryption means are stored in the execution order of the original programs, but the present invention is not limited to this. Furthermore, it would be convenient to increase the encryption strength if a required number of encrypted divided programs are combined and then encrypted again using a desired encryption means.

In an embodiment of the invention, the comviator is monitored.

Although a keyboard and a )ptube disk drive are connected, the user is not limited to these, and may select various external devices that meet the user's purpose. Furthermore, it is obvious that what is to be encrypted may be data other than programs, and what is to be recorded thereon may be any recording medium such as a magnetic tape or an i2 RAM card other than a floppy disk.

(Effects of the Invention) As explained above, the present invention divides the program or data to be protected into the required number of pieces, encrypts each program or data with a desired encryption means and saves the program or data. If you use PfI! ! By connecting the decryption means to the M-spec transfer unit, programs can be executed or data can be accessed. Therefore, it is possible to prevent unauthorized use by a third party who has just obtained the decryption means, and to prevent the information from being transferred. Effective in protection.

[Brief explanation of the drawing]

FIG. 1 is a two-chart diagram showing an embodiment of encrypting a program according to the present invention, FIG. 2 is a configuration diagram showing an embodiment of an expansion device according to the present invention, and FIG. 3 is a diagram showing an embodiment of the expansion device according to the present invention. FIG. 2 is a configuration diagram showing another embodiment of an encryption device showing an embodiment of decryption based on an encrypted program according to the above. AO to An...... Transfer section + Dl
, D2...Decoding means, ■...
...Expansion device. 2...-...CPU, 3...
····memory. 4...Input/output section, 5...
... Combiator, 6...
・・・・・・CRT,
7 ・・・・・・ ・Keyboard,
8...Full 2B disc. 9...Foo, b disk drive. 10.11... Encrypted ROM,
12゜13・・・・・・Decryption ROM,
14...... Expansion device, 15-0 to 15
-3...Transfer section 16...
ROM, 17...
CPU, 18 ・・・・・・・・・R
AM, 19... Input/output unit, 20... Encryption device. Patent applicant: Toyo Tsushinki Co., Ltd. Figure 1 Figure 5

Claims (1)

[Claims] 1. Divide information into a required number of pieces, add selection information for specifying the next information to each desired piece of divided information, and send each piece of information to a desired encryption means. An information protection method characterized by encryption. 2. When decrypting information encrypted by the method described in claim 1, a plurality of transfers that selectively connect the decryption means corresponding to the encryption means of each divided information and the required decryption means 1. A method for protecting information, comprising: specifying a transfer section corresponding to the selected information; and decoding the selected information by a decoding means connected to the transfer section.