JPH1027135A - Method and device for storing electronic information - Google Patents

Abstract

PROBLEM TO BE SOLVED: To store a large amount of electronic information, whose copy is limited, at low cost and enable efficient reading and writing by deciding electronic information in a storage device having no copy preventing function by a tamper-resisting device, and using only electronic information which is not copied. SOLUTION: Electronic information (message) to be stored is inputted to the tamper-resisting device 100, a computing element 110 calculates a 1st message identifier according to the message and stores it in a storage device 120, and the message is stored in a general storage device 200. To use this message, the message stored in the temporary storage device 200 is read in the tamper- resisting device 100 to calculate a 2nd corresponding message identifier. When a message identifier matching it is not stored in the tamper-resisting device 100, it is decided that this message is not copied, this message is used, and the stored message identifier and message are deleted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for storing electronic information, and more particularly, to a method and apparatus for storing electronic information for storing electronic information. More specifically, the present invention relates to an electronic information storage method and apparatus for storing electronic information (message) whose copy is to be restricted.

[0002]

2. Description of the Related Art When storing a message whose copy is to be restricted, the message is stored in a storage device in the tamper-resistant device, or the message is encrypted using a secret key in the tamper-resistant device. This is realized by storing the message in a general storage device.

Here, a tamper-resistant device is a device that can read and write information from inside the device but cannot read and write from outside the device. For example, a device having a mechanism in which an inert gas is injected into a storage device, and when the device is opened, the inert gas is scattered and the inside of the storage device is oxidized, so that stored contents are lost or information is lost. It is.

[0004]

However, in the above-described method of storing a message in a tamper-resistant device, the tamper-resistant device generally has a small storage capacity, and has a higher cost than other devices having the same storage capacity. Since it is expensive, there is a problem that the cost is high.

In the method of encrypting a message and storing it in a general storage device, it is necessary to perform an encryption / decryption process every time the message is read / written, so that it takes a long processing time. is there. SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide an electronic information storage method and apparatus which can store a large number of messages whose copying is to be restricted at low cost and can read / write efficiently. I do.

[0006]

SUMMARY OF THE INVENTION The present invention provides a first storage device having a physical copy protection mechanism and a tamper-resistant device having an arithmetic unit connected to the first storage device. When electronic information whose copy is to be restricted is stored using the second storage device which is connected to perform storage and read and does not have the physical copy protection function, and the electronic information is used, a tamper-resistant The device determines whether the electronic information stored in the second storage device has been copied, and uses only the electronic information that has not been copied.

FIG. 1 is a diagram for explaining the principle of the present invention. According to the present invention, when electronic information (hereinafter, referred to as a message) is stored, a message to be stored is fetched into a tamper-resistant device (step 1). First
Is calculated (step 2), the calculated first message identifier is stored in the first storage device of the tamper-resistant device (step 3), and the message is stored in the second storage device (step). .

Further, according to the present invention, when the stored message is used, the message stored in the second storage device is read into a tamper-resistant device (step 5), and the message is processed by an arithmetic unit in the tamper-resistant device. Is calculated (step 6), and it is determined whether a message identifier that matches the second message identifier is stored in the tamper-resistant device (step 7). Determines that the message has not been copied, uses the message (step 8), deletes the message identifier of the used message from within the tamper-resistant device, and deletes the message from the second storage device (step 8). Step 9).

Further, according to the present invention, when a message identifier matching the second message identifier is stored in the tamper-resistant device, information indicating that the message has not been copied is added to the message. In addition, the present invention determines that the message read from the second storage device is copied when the message identifier that matches the second message identifier is not stored in the tamper-resistant device. Is destroyed (Step 1
0).

[0010] Further, the present invention uses a hash function when calculating the second message identifier. Further, the present invention uses electronic signature information as information indicating that the message has not been copied.

FIG. 2 is a diagram showing the principle of the present invention. The electronic information storage device of the present invention provides electronic information to be stored
Computing means 110 for generating a message identifier based on the message identifier, a first storage means 120 for storing the message identifier, and a control means 130 for controlling the first storage means 120 and an external storage device. Tamper-resistant device 1 including a physical copy protection mechanism for electronic information
00, and a second storage unit 200 connected via the tamper-resistant device 100 to store and read information, and not having the physical copy protection function.

The arithmetic means 120 calculates a first message identifier based on a message to be stored taken in the tamper-resistant device 100, and the second storage means. Second message identifier calculation means for calculating a second message identifier based on the message read from the means 200.

The control means 130 stores the first message identifier calculated by the first message identifier calculation means in the first storage means, and stores the message in the second storage means. Including storage control means.

When the stored message is used, the control means 130 reads the message stored in the second storage means 200 into the tamper-resistant device 100 and the arithmetic means 120 The first message identifier that matches the calculated second message identifier is stored in the first storage unit 12 of the tamper-resistant device 100.
0, and a message acquiring unit that, if stored, determines that the message is not copied and acquires the message stored in the second storage unit 200. And a message identifier deleting unit for deleting the message identifier of the acquired message from within the tamper-resistant device 100, and a message deleting unit for deleting the message from the second storage unit 200.

Further, the above-mentioned message acquiring means is provided in the second
When a message identifier that matches the message identifier stored in the tamper-resistant device 100 is stored in the tamper-resistant device 100, a confirmation information adding unit that adds information indicating that the message is not copied to the message is included.

When the determining means determines that the message identifier matching the second message identifier is not stored in the tamper-resistant device 100, the control means 130 sets the second storage means 200 The message read from is determined to have been copied, and includes a message discarding means for discarding the message.

Further, the first message identifier calculating means and the second message identifier calculating means of the arithmetic means 110 use a hash function when calculating the first message identifier and the second message identifier. . Also,
The confirmation information adding means uses the electronic signature information as information indicating that the message has not been copied.

The control means 130 includes a message providing means for providing the electronic signature information in combination with the message when providing the message to the request source. As described above, the present invention has a configuration in which a tamper-resistant device and a general storage device are used in combination. In such a configuration, by confirming the presence of the message identifier in the tamper-resistant device, it is possible to detect that the message captured in the device is a copy, so that copying to an inexpensive general storage device can be performed. It is possible to store messages that you want to restrict.

Further, since only the identifier is stored in the tamper-resistant device, the capacity can be reduced. further,
Since there is no need to encrypt / decrypt the entire message,
It is possible to read / write at high speed.

[0020]

FIG. 3 shows a configuration of an electronic information storage device according to the present invention. The configuration shown in FIG.
0 and a general storage device 200. The tamper-resistant device 100 includes a control unit 130, a computing unit 110, the control unit 1
30 has a storage device 120 having a physical copy protection mechanism.

The general storage device 200 has no copy protection mechanism, is connected to the tamper-resistant device 100, and stores and reads information via the tamper-resistant device 100. When storing electronic information (message) whose copy is to be restricted, the control unit 130 takes the message into the tamper-resistant device 100 and transfers it to the arithmetic unit 110 and the general storage device 200.

The arithmetic unit 110 calculates a message identifier corresponding to the received message by using a hash function. The message identifier calculated in this way is stored in the storage device 120. The calculation by the hash function is described in, for example, “Introduction to Cryptography Theory” by Eiji Okamoto pp. See 138 for a function utilizing a one-way hash function.

Further, when there is a message read request, the control unit 130 takes the message from the general storage device 200 into the tamper-resistant device 100 and transfers it to the arithmetic unit 110. The arithmetic unit 110 calculates a check message identifier corresponding to the captured message, and transfers the identifier to the control unit 130.

As shown in FIG. 4, the control unit 130 includes a request acquisition unit 131, a message transfer unit 132, a message identifier determination unit 133, a confirmation information addition unit 134, a message provision unit 135, and a deletion control unit 136. . Upon receiving the message to be stored from the message storage requester, the request acquisition unit 131 transfers the message to the message transfer unit 132. In addition, a message acquisition request is received from the message requester and transferred to the message transfer unit 132.

The message transfer unit 132 stores the message to be stored from the message storage requester in the general storage device 2.
Transfer to 00. When a message is read from the general storage device 200 based on the request acquired from the request acquisition unit 131, the message is transferred to the arithmetic unit 110.

The message identifier determining unit 133 determines whether a message identifier matching the check message identifier generated by the arithmetic unit 110 is stored in the storage device 110. If the same message identifier exists in the storage device 110 as a result of the determination, the received message is transferred to the confirmation information adding unit 134.

The confirmation information adding unit 134 adds digital signature information indicating that the message is not a copied message to the message acquired from the message identifier determining unit 133. The message providing unit 135 includes the confirmation information adding unit 1
At 34, the message with the electronic signature information is provided to the message requester.

When the message identifier determining unit 133 determines that the message is not a copied message, the deletion control unit 136 deletes the message stored in the general storage device 200 and stores the message in the storage device 120. The message identifier corresponding to the message in question is deleted. If the same message identifier does not exist in the storage device 110 as a result of the determination, the captured message is determined to have been copied, and the message is discarded.

[0029]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 5 is a flowchart at the time of storing a message according to an embodiment of the present invention. Step 101) The control unit 130 of the tamper-resistant device 100 acquires the message (Msg) from the message storage, and converts the message into the arithmetic unit 11
Transfer to 0.

Step 102) The arithmetic unit 110 hashes the transferred message (Msg) by Mid = hash (Msg) using a hash function, and uses the hashed message as a message identifier (Mid) as a control unit. Transfer to 130.

Step 103) The message transfer unit 132 of the control unit 130 sends the message received from the message store in step 101 to the general storage device 20.
Store to 0. Step 104) The message transfer unit 132 of the control unit 130 stores the message identifier (Mid) transferred from the calculation unit 110 in the storage device 120.

Next, a process for reading a message stored in the general storage device 200 will be described. FIG.
6 is a flowchart at the time of reading a message according to an embodiment of the present invention. Step 201) The control unit 130 of the tamper-resistant device 100 receives a message provision request from a message requester.

Step 202) The message transfer unit 132 of the control unit 130 reads the message (Msg) corresponding to the request from the general storage device 200, and transfers the message (Msg) to the arithmetic unit 110. Step 203) The operation unit 110 determines the message (Msg)
Is hashed by using MID = hash (Msg) using a hash function, and the hashed message is transferred to the control unit 130 as a message identifier (MID).

Step 204) The message identifier judging section 133 of the control section 130 compares the message identifier (Mid) stored in the storage device 110 with step 203.
It is determined whether or not the message identifiers (MIDs) generated in step 1 match. If they match (Mid = MID), the process moves to step 206, and if they do not match (Mid @ MI
In D), the process proceeds to step 205.

Step 205) If they do not match, the deletion control unit 136 of the control unit 130
Then, the message (Msg) read out from is discarded, and the process ends. Step 206) If the message identifiers match, the confirmation information adding unit 134 of the control unit 130 sets the signature information (S) for the message (Msg).
Generate The signature generation method uses an existing signature creation method. For example, the signature is generated by a signature generation method described in Japanese Patent Application Laid-Open No. 8-87559. The signature information (S) generated in this way is added to the message (Msg) to make “S + Msg” and transferred to the message providing unit 135.

Step 207) The message providing unit 135 of the control unit 130 sets the combination of the message (Msg) generated in step 206 and the signature information (S) “S + M
sg "to the message request source. It is assumed that the message providing unit 135 has acquired the address information of the request source when the request acquisition unit 131 has received the request.

Step 208) The deletion control unit 136 of the control unit 130 deletes the message identifier (Mid) stored in the storage device 110 and deletes the message (Msg) stored in the general storage device 200. . Thus, the person who issued the message read request receives the information in which the signature information (S) is added to the message (Msg), determines that the message is not copied, and uses the message.

In the above embodiment, the storage device 1
In generating a message identifier to be stored in the H.20, a hash operation is used.
Computation time is 500 times longer than encryption processing such as D5 and DES
Although the speed is twice as high, the method is employed. However, the present invention is not limited to this example, and an operation method having an equivalent operation function and a function of masking a message identifier can also be applied.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications and applications are possible within the scope of the claims.

[0040]

As described above, according to the electronic information storage method and apparatus of the present invention, as a method of storing a message in a tamper-resistant device, the information (hash information) stored in the tamper-resistant device is a message. Irrespective of the size of the tamper-resistant device, even if the storage capacity of the tamper-resistant device is small, a large amount of data (electronic information) stored in a general storage device Can be prevented from being copied.

According to the present invention, as a method of encrypting a message and storing it in a general storage device, at the time of writing a message, it is not necessary to encrypt the entire message, and only a process of hashing the message may be performed. Therefore, the writing speed is improved.

Further, at the time of reading a message, it is not necessary to decrypt the entire message, and it is sufficient to perform a process of hashing the message and generating a signature, thereby improving the reading speed. Further, in the method of encrypting / decrypting all the messages, the processing time increases in proportion to the size (byte length) of the message. However, according to the present invention, the general encryption is performed by using the hash function. 50 than speed
Since the processing speed is about 0 times, the change in the processing amount due to the size of the message is small.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining the principle of the present invention.

FIG. 2 is a diagram for explaining the principle of the present invention.

FIG. 3 is a configuration diagram of an electronic information storage device of the present invention.

FIG. 4 is a configuration diagram of a control unit of the present invention.

FIG. 5 is a flowchart at the time of storing a message according to an embodiment of the present invention.

FIG. 6 is a flowchart at the time of reading a message according to an embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 tamper-resistant device 110 arithmetic unit, arithmetic unit 120 first storage unit, storage device 130 control unit, control unit 131 request acquisition unit 132 message transfer unit 133 message identifier determination unit 134 confirmation information addition unit 135 message provision unit 136 deletion control Unit 200 Second storage means, general storage device

Claims (16)

[Claims] 1. A first storage device having a physical copy protection mechanism and a tamper-resistant device having an arithmetic unit connected to the first storage device are connected so as to store and read information. When electronic information whose copy is to be restricted is stored in the second storage device having no physical copy protection function, and the electronic information is used, the tamper-resistant device stores the electronic information in the second storage device. An electronic information storage method comprising: determining whether stored electronic information has been copied; and using only the non-copied electronic information. 2. When storing the electronic information (hereinafter, referred to as a message), a message to be stored is taken into the tamper-resistant device, and the arithmetic unit of the tamper-resistant device adds the message to the fetched message. Calculating a first message identifier based on the first message identifier, storing the calculated first message identifier in the first storage device of the tamper-resistant device, and storing the message in the second storage device. 1. The electronic information storage method according to 1. 3. When using the stored message, the message stored in the second storage device is read into the tamper-resistant device, and the arithmetic unit in the tamper-resistant device converts the message into the message. Calculating a corresponding second message identifier, determining whether a message identifier matching the second message identifier is stored in the tamper resistant device,
If it is stored, it is determined that the message has not been copied, the message is used, and the message identifier of the used message is deleted from the first storage device of the tamper-resistant device; 2. The method according to claim 1, wherein the message is deleted from the second storage device.
And the electronic information storage method according to 2. 4. When a message identifier matching the second message identifier is stored in the tamper-resistant device, information indicating that the message has not been copied is added to the message. Electronic information storage method described. 5. When a message identifier that matches the second message identifier is not stored in the tamper-resistant device, it is determined that the message read from the second storage device has been copied. 4. The electronic information storage method according to claim 3, wherein the message is discarded. 6. The electronic information storage method according to claim 3, wherein a hash function is used when calculating the second message identifier. 7. The electronic information storage method according to claim 4, wherein electronic signature information is used as the information indicating that the message has not been copied. 8. An arithmetic unit for generating a message identifier based on electronic information to be stored (hereinafter, referred to as a message), a first storage unit connected to the arithmetic unit and storing the message identifier, A tamper-resistant device that includes a first storage unit, the arithmetic unit, and a control unit that controls an external storage device, and that has a physical copy protection mechanism for electronic information; An electronic information storage device, comprising: a second storage unit connected to perform reading and not having the physical copy protection function. 9. The first message identifier calculating means for calculating a first message identifier based on the message to be stored taken in the tamper-resistant device, and the second storage device. 9. The electronic information storage device according to claim 8, further comprising: a second message calculating unit that calculates a second message identifier based on the message acquired from the second message. 10. The control means stores the first message identifier calculated by the first message identifier calculation means in the first storage means, and stores the message in the second storage means. 10. The electronic information storage device according to claim 8, further comprising a storage control unit that performs storage control. 11. The control unit includes: a message reading unit that reads the message stored in the second storage unit into the tamper-resistant device; and a message identifier that matches the second message identifier generated by the calculation unit. A determination unit that determines whether the message identifier to be stored is stored in the first storage unit of the tamper-resistant device; if the message identifier is stored, it is determined that the message is not copied; A message acquisition unit that acquires a message stored in a storage unit, a message identifier deletion unit that deletes a message identifier of the acquired message from the tamper-resistant device, and a message from the second storage unit. 9. The electronic information storage device according to claim 8, further comprising a message deleting unit. 12. The message acquisition means, when a message identifier matching the second message identifier is stored in the tamper-resistant device, sends information indicating that the message has not been copied to the message. The electronic information storage device according to claim 11, further comprising a confirmation information adding unit that adds the confirmation information to the electronic information. 13. The second storage means, when the control means determines that a message identifier matching the second message identifier is not stored in the tamper-resistant device. 12. The electronic information storage device according to claim 11, further comprising: a message discarding unit that determines that the message read from the message has been copied and discards the message. 14. The arithmetic unit according to claim 9, wherein a hash function is used when calculating the first message identifier and the second message identifier.
Electronic information storage device as described. 15. The electronic information storage device according to claim 12, wherein the confirmation information adding unit uses electronic signature information as information indicating that the message has not been copied. 16. The electronic information storage device according to claim 11, wherein the control unit includes a message providing unit configured to provide the electronic signature information as a set when providing the message to a request source. .