Information processing device, method, and program

Abstract

According to the present invention, when there is a transaction for a blockchain, a processor determines whether or not the transaction could be recorded in the blockchain under a predetermined condition, and changes processing for the transaction between when the transaction could be recorded in the blockchain and when the transaction could not be recorded.

Description

Information processing device, method and program

[0001] The present disclosure relates to an information processing device, a method, and a program.

[0002] In a blockchain that manages information using multiple blocks, various functions can be realized by programs (hereafter referred to as smart contracts) that run on the blockchain nodes that make up the blockchain. In the process in which a blockchain node executes a smart contract in response to a request to realize a transaction, the transaction is imported into each blockchain node in the blockchain, and the data stored in each block is updated according to the transaction.

[0003] Because blockchain is an open system that does not require an administrator, there is a possibility that malicious users may slip in. To prevent such transactions by malicious users, various methods for verifying transactions have been proposed (see, for example, Japanese Patent No. 7298716).

[0004] On the other hand, with blockchain, there is a possibility that data recorded on the blockchain may be leaked to malicious users.

[0005] The present disclosure has been made in consideration of the above circumstances, and aims to make it possible to detect data leakage from a blockchain.

[0006] The information processing device according to the present disclosure is an information processing device in an information processing system that uses a blockchain that manages data in blocks, and is equipped with at least one processor. When a transaction is made to the blockchain, the processor determines whether the transaction can be recorded in the blockchain under specified conditions, and changes the processing for the transaction depending on whether the transaction can be recorded in the blockchain or not.

[0007] In the information processing device according to the present disclosure, the transaction may include a request to reference data.

[0008] In addition, in the information processing device according to the present disclosure, the processor may permit the sender of the transaction to access the data if the transaction can be recorded in the blockchain, and may deny the sender of the transaction access to the data if the transaction cannot be recorded in the blockchain.

[0009] In addition, in the information processing device according to the present disclosure, the processor may transmit the data to the sender of the transaction when access to the data is permitted, and record the data transmission history in the blockchain.

[0010] In addition, in the information processing device according to the present disclosure, the transmission history may include a transmission result indicating whether or not the data transmission was successful.

[0011] In addition, in the information processing device according to the present disclosure, the processor may determine whether or not it has received a reference result indicating that the sender of the transaction has referenced the data, and if it has received the reference result, record the reference result in the blockchain.

[0012] The information processing method disclosed herein is an information processing method in an information processing system that uses a blockchain that manages data in blocks, in which, when a transaction to the blockchain is made, a computer determines whether the transaction can be recorded in the blockchain under specified conditions, and changes the processing of the transaction depending on whether the transaction can be recorded in the blockchain or not.

[0013] The information processing program according to the present disclosure is an information processing program in an information processing system that uses a blockchain that manages data in blocks, and when a transaction is made to the blockchain, causes a computer to execute a procedure for determining whether the transaction can be recorded in the blockchain under specified conditions, and a procedure for changing the processing of the transaction depending on whether the transaction can be recorded in the blockchain or not.

[0014] According to the present disclosure, data leakage from the blockchain can be detected.

[0015] FIG. 1 is a diagram showing a schematic configuration of an information processing system to which an information processing device according to an embodiment of the present disclosure is applied. FIG. 2 is a diagram showing a hardware configuration of an information processing device according to this embodiment. FIG. 3 is a block diagram showing a functional configuration of an information processing device according to this embodiment.

[0016] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. FIG. 1 is a diagram illustrating a schematic configuration of an information processing system to which an information processing device according to an embodiment of the present disclosure is applied. In the information processing system 1 illustrated in FIG. 1, a network is formed using a blockchain that manages data in blocks. In each block, information is managed by a blockchain node 2. Each blockchain node 2 is managed by a constituent organization with independent authority. A smart contract 3 is applied to each blockchain node 2. The smart contract 3 is a program that is executed in response to a transaction in accordance with specified rules shared among users who are participants in the blockchain. The smart contract is an example of an information processing program according to the present disclosure.

[0017] A blockchain user can use the blockchain by accessing the blockchain network from their own terminal device 5. For example, a user can send a transaction to the blockchain to reference data, and reference data recorded in the blockchain.

[0018] The blockchain node 2 is composed of devices such as a workstation, a server computer, a personal computer, etc. The devices include the information processing device according to this embodiment.

[0019] FIG. 2 is a diagram showing the hardware configuration of devices constituting a blockchain node 2 according to this embodiment, i.e., an information processing device according to this embodiment. As shown in FIG. 2, the information processing device 10 includes a CPU (Central Processing Unit) 11, non-volatile storage 13, and memory 16 as a temporary storage area. The information processing device 10 also includes a display 14 such as a liquid crystal display, an input device 15 such as a keyboard and a mouse, and a network I / F (Interface) 17 connected to a network (not shown). The CPU 11, storage 13, display 14, input device 15, memory 16, and network I / F 17 are connected to a bus 18. The CPU 11 is an example of a processor in the present disclosure.

[0020] The storage 13 is realized by a hard disk drive (HDD), a solid state drive (SSD), a flash memory, etc. The storage 13 as a storage medium stores the information processing program 12 installed in the information processing device 10. The CPU 11 reads the information processing program 12 from the storage 13, expands it in the memory 16, and executes the expanded information processing program 12, i.e., the smart contract 3.

[0021] The information processing program 12 is stored in a state accessible from the outside in a storage device of a server computer connected to a network or in a network storage, and is downloaded and installed in response to a request into a computer constituting the information processing device 10. Alternatively, the information processing program 12 is recorded on a recording medium such as a DVD (Digital Versatile Disc) or a CD-ROM (Compact Disc Read Only Memory) and distributed, and is installed into a computer constituting the information processing device 10 from the recording medium.

[0022] 3 is a block diagram showing the functional configuration of the information processing device 10. As shown in FIG. 3, the information processing device 10 includes an acquisition unit 21, a determination unit 22, and a processing unit .

[0023] The acquisition unit 21 acquires transactions sent to the blockchain from the terminal device 5 of a blockchain user. In this embodiment, the transaction includes a request to access data managed in the blockchain, i.e., data stored in the blockchain node 2.

[0024] When a transaction occurs, the determination unit 22 determines whether the transaction was able to be recorded in the blockchain under predetermined conditions. Specifically, when the transaction includes a data reference request, the determination unit 22 determines whether the data reference request included in the transaction was able to be stored in the blockchain node 2. Note that the predetermined condition may be that the transaction was able to be recorded in the blockchain node 2 immediately, or that the transaction was able to be recorded in the blockchain node 2 after a predetermined time has elapsed since the transaction was received.

[0025] Here, a situation in which a transaction cannot be recorded in the blockchain may occur, for example, when some kind of error occurs in the blockchain. Furthermore, in a blockchain, multiple transactions may be sent at once, but which transactions are stored in the blockchain node 2 depends on the user who created the blockchain node 2. Therefore, when multiple transactions are received, even if they are stored in the blockchain node 2, the storage may be canceled after a certain period of time has passed. Even in this case, a situation in which a transaction cannot be recorded in the blockchain may occur.

[0026] The processing unit 23 changes the processing for the transaction depending on whether the transaction was successfully recorded in the blockchain or not. Specifically, if the transaction was successfully recorded in the blockchain, the processing unit 23 permits the sender of the transaction to refer to the data, and if the transaction was not successfully recorded in the blockchain, the processing unit 23 denies the sender of the transaction from referring to the data.

[0027] Furthermore, if access to the data is permitted, the processing unit 23 transmits the data to the sender of the transaction. Then, the processing unit 23 records a data transmission history in the blockchain. The transmission history includes a transmission result indicating whether or not the data transmission was successful. That is, if the data transmission was successful, the transmission result to that effect is included, and if the data transmission failed, the transmission result to that effect is included.

[0028] When data is successfully transmitted from the blockchain and the sender of the transaction receives the data, the sender sends a reference result indicating that the data has been referenced to the blockchain. When the blockchain node 2 receives the reference result, it records the received reference result in the blockchain.

[0029] As a result, when a transaction is received at the blockchain node 2 and access to the data is permitted, the transaction, the data transmission history, and the results of the data access by the transaction sender are recorded in the blockchain as transaction history.

[0030] Here, recording any information in the blockchain means storing the information in the blockchain node 2.

[0031] Next, the processing performed in this embodiment will be described. Fig. 4 is a flowchart showing the processing performed in this embodiment. When the acquisition unit 21 acquires a transaction sent from the terminal device 5, processing of the information processing program 12, i.e., the smart contract, begins.

[0032] First, the determination unit 22 determines whether the transaction has been recorded in the blockchain under predetermined conditions (step ST1). If the result of step ST1 is negative, the processing unit 23 denies the sender of the transaction access to the data (step ST2), and the process ends.

[0033] If step ST1 is positive, the processing unit 23 permits the sender of the transaction to access the data (step ST3), transmits the data to the sender of the transaction (step ST4), and records the data transmission history in the blockchain (step ST5).

[0034] Then, the processing unit 23 starts monitoring whether or not a reference result has been received from the sender of the transaction (step ST6), and if step ST6 is positive, records the reference result in the blockchain (step ST7), and ends the processing.

[0035] As described above, in this embodiment, when a transaction is made to the blockchain, it is determined whether the transaction can be recorded in the blockchain under predetermined conditions, and the processing of the transaction is changed depending on whether the transaction can be recorded in the blockchain or not. This prevents a transaction from being accepted without leaving a history of the transaction in the blockchain. Furthermore, by referencing the transaction recorded in the blockchain, the sender of the transaction can be identified. Therefore, if the sender is a malicious user, it is possible to detect the leakage of data recorded in the blockchain.

[0036] In particular, in this embodiment, when a transaction includes a reference to data recorded in the blockchain, if the transaction can be recorded in the blockchain, the sender of the transaction is permitted to reference the data, and if the transaction cannot be recorded in the blockchain, the sender of the transaction is denied access to the data. This ensures that transaction data is not referenced without leaving a history of the transaction in the blockchain. Furthermore, if the sender is a malicious user, it is possible to reliably detect the leakage of data recorded in the blockchain.

[0037] In addition, by recording the data transmission history in the blockchain, it is possible to record in the blockchain whether the data was transmitted successfully or not.

[0038] Furthermore, by recording the reference result indicating that the sender of the transaction has referenced the data in the blockchain, it is possible to keep a record of which sender has referenced the data. Therefore, if the sender is a malicious user, it is possible to reliably detect the leakage of data recorded in the blockchain.

[0039] In the above embodiment, the history of data transmission to the sender of the transaction is recorded in the blockchain, but this is not limited to this. The history of data transmission may not be recorded in the blockchain.

[0040] In addition, in the above embodiment, the reference result from the sender of the transaction is recorded in the blockchain, but this is not limited to this. The reference result from the sender of the transaction may not be recorded in the blockchain.

[0041] Furthermore, in the above embodiment, for example, the information processing device 10 may use the following various processors as the hardware structure of processing units that perform various processes, such as the acquisition unit 21, the determination unit 22, and the processing unit 23. The various processors include, as described above, a CPU, which is a general-purpose processor that executes software (programs) and functions as various processing units, as well as dedicated electrical circuits, such as programmable logic devices (PLDs) that are processors whose circuit configuration can be changed after manufacture, such as FPGAs (Field Programmable Gate Arrays), and ASICs (Application Specific Integrated Circuits), which are processors with a circuit configuration designed specifically for performing specific processes.

[0042] A single processing unit may be configured with one of these various processors, or may be configured with a combination of two or more processors of the same or different types (for example, a combination of multiple FPGAs or a combination of a CPU and an FPGA).Furthermore, multiple processing units may be configured with a single processor.

[0043] Examples of configuring multiple processing units with a single processor include: first, a form in which one processor is configured with a combination of one or more CPUs and software, as typified by computers such as client and server computers, and this processor functions as multiple processing units; second, a form in which a processor is used to realize the functions of an entire system including multiple processing units with a single IC (Integrated Circuit) chip, as typified by systems on chips (SoCs); in this way, various processing units are configured using one or more of the above-mentioned various processors as a hardware structure.

[0044] Furthermore, more specifically, the hardware structure of these various processors can be an electric circuit that combines circuit elements such as semiconductor elements.

[0045] The following are supplementary clauses of the present disclosure. (Supplementary clause 1) An information processing device in an information processing system using a blockchain that manages data in blocks, comprising at least one processor, wherein, when a transaction to the blockchain is received, the processor determines whether the transaction could be recorded in the blockchain under predetermined conditions, and changes the processing of the transaction depending on whether the transaction could be recorded in the blockchain or not. (Supplementary clause 2) The information processing device according to Supplementary clause 1, wherein the transaction includes a request to reference the data. (Supplementary clause 3) The information processing device according to Supplementary clause 2, wherein, if the transaction could be recorded in the blockchain, the processor permits the sender of the transaction to reference the data, and, if the transaction could not be recorded in the blockchain, denies the sender of the transaction from accessing the data. (Supplementary clause 4) The information processing device according to Supplementary clause 3, wherein, if the processor is permitted to access the data, the processor transmits the data to the sender of the transaction, and records a transmission history of the data in the blockchain. (Supplementary Item 5) The information processing device according to Supplementary Item 4, wherein the transmission history includes a transmission result indicating whether the data was transmitted normally. (Supplementary Item 6) The information processing device according to Supplementary Item 4 or 5, wherein the processor determines whether a reference result indicating that the sender of the transaction has referenced the data has been received, and if the reference result has been received, records the reference result in the blockchain. (Supplementary Item 7) An information processing method in an information processing system using a blockchain that manages data in blocks, wherein, when a transaction is made to the blockchain, a computer determines whether the transaction could be recorded in the blockchain under specified conditions, and changes processing for the transaction depending on whether the transaction was able to be recorded in the blockchain or not.(Supplementary Item 8) An information processing program in an information processing system using a blockchain that manages data in blocks, the information processing program causing a computer to execute, when a transaction is made to the blockchain, a procedure for determining whether the transaction can be recorded in the blockchain under specified conditions, and a procedure for changing the processing of the transaction depending on whether the transaction can be recorded in the blockchain or not.

[0046] REFERENCE SIGNS LIST 1 Information processing system 2 Node 3 Smart contract 5 Terminal device 10 Information processing device 11 CPU 12 Information processing program 13 Storage 14 Display 15 Input device 16 Memory 17 Network I / F 18 Bus 21 Acquisition unit 22 Determination unit 23 Processing unit

Claims

1. An information processing device in an information processing system that uses a blockchain that manages data in blocks, comprising at least one processor, wherein when a transaction is made to the blockchain, the processor determines whether the transaction can be recorded to the blockchain under specified conditions, and changes the processing for the transaction depending on whether the transaction can be recorded to the blockchain or not.

2. The information processing device according to claim 1, wherein the transaction includes a request to reference the data.

3. The information processing device of claim 2, wherein the processor permits the sender of the transaction to access the data if the transaction can be recorded on the blockchain, and denies the sender of the transaction access to the data if the transaction cannot be recorded on the blockchain.

4. The information processing device according to claim 3, wherein the processor, if permitted to access the data, transmits the data to the sender of the transaction and records a transmission history of the data in the blockchain.

5. The information processing device according to claim 4, wherein the transmission history includes a transmission result indicating whether the data was transmitted normally or not.

6. An information processing device as described in claim 4 or 5, wherein the processor determines whether or not it has received a reference result indicating that the sender of the transaction has referenced the data, and if it has received the reference result, records the reference result in the blockchain.

7. An information processing method in an information processing system using a blockchain that manages data in blocks, wherein, when a transaction is made to the blockchain, a computer determines whether the transaction can be recorded in the blockchain under specified conditions, and changes the processing of the transaction depending on whether the transaction can be recorded in the blockchain or not.

8. An information processing program in an information processing system using a blockchain that manages data in blocks, the information processing program causing a computer to execute, when a transaction is made to the blockchain, a procedure for determining whether the transaction can be recorded in the blockchain under specified conditions, and a procedure for changing the processing of the transaction depending on whether the transaction can be recorded in the blockchain or not.

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