JP2018157432A - Generation device, verification device, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanism for enhancing confidentiality of dealer identification information on transaction between a plurality of terminals connected to a network.SOLUTION: A generation device is a generation device that generates a transaction identification information used for a block chain for assuring propriety of transaction between a plurality of terminals connected to a network. The generation device comprises: a calculation part that calculates a hush value of the block just before the block in an open state from a plurality of blocks included in the block chain as a block hush value; and an identification information generation part that generates dealer identification information used for the transaction on the basis of the block hush value calculated by the calculation part, secret key information which is different in each dealer who executes the transaction, and the dealer identification information that is different in each dealer.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a generation device, a verification device, and a program.

  2. Description of the Related Art Conventionally, a technique related to a block chain for ensuring the validity of a transaction between a plurality of terminals connected to a network is known.

Satoshi Nakamoto. Bitcoin: A peer-to-peer electronic cash system, 2008. Sompolinsky, Y., Zohar, A .: Accelerating bitcoin's transaction processing.Fast money grows on trees, not chains.IACR Cryptology ePrint Archive 2013 (2013) 881. Lewenberg, Y., Sompolinsky, Y., Zohar, A .: Inclusive block chain protocols.In:Financial Cryptography and Data Security-19th International Conference, FC2015, San Juan, Puerto Rico, January 26-30, 2015, Revised Selected Papers (2015) 528-547

Each block constituting the block chain includes identification information of a trader who conducts the trade. Here, in order to improve the confidentiality of the transaction of the trader, it is preferable that the identification information of the trader is anonymous.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a mechanism for improving the confidentiality of transaction identification information of a transaction among a plurality of terminals connected to a network.

  (1) One aspect of the present invention is a generation device that generates transaction identification information used for a block chain for guaranteeing the legitimacy of a transaction between a plurality of terminals connected to a network. Among a plurality of included blocks, a calculation unit that calculates a hash value of a block immediately before a block in an open state as a block hash value, the block hash value calculated by the calculation unit, and a transaction that performs the transaction And an identification information generating unit that generates transaction identification information used for the transaction based on different secret key information for each transaction and different transaction identification information for each transaction.

  (2) According to one aspect of the present invention, in the generation device described in (1), an electronic signature generation that generates an electronic signature based on the block hash value calculated by the calculation unit and the secret key information The electronic signature generation unit generates a hash value of the electronic signature generated by the electronic signature generation unit as a signature hash value, and the identification information generation unit includes the signature hash value and the trader identification information. Based on the above, the transaction identification information is generated.

  (3) According to one aspect of the present invention, in the generation device according to (1) or (2), the calculation unit includes a plurality of blocks in a case where there are a plurality of blocks immediately before a block in an open state. The block hash value is calculated based on each hash value of the block.

  (4) One aspect of the present invention is a verification device that verifies transaction identification information used in a block chain for guaranteeing the validity of a transaction between a plurality of terminals connected to a network. A trader identification information acquisition unit that acquires transaction identification information used when performing a transaction, an electronic signature acquisition unit that acquires an electronic signature of the trader, and a hash value of the electronic signature acquired by the electronic signature acquisition unit A calculation unit that calculates, a decryption unit that decrypts the transaction identification information based on the hash value calculated by the calculation unit, decryption information that is a result of the decryption unit decrypting the transaction identification information, and the trader It is a verification apparatus provided with the determination part which determines whether the trader identification information which identifies is equal.

  (5) According to one aspect of the present invention, a computer that generates transaction identification information used for a block chain for guaranteeing the legitimacy of a transaction between a plurality of terminals connected to a network is included in the plurality of blocks included in the block chain. Among the blocks, the calculation step of calculating the hash value of the block immediately before the block in the open state as the block hash value, the block hash value calculated by the calculation step, and each trader performing the transaction An identification information generating step for generating transaction identification information used for the transaction based on different secret key information and different transaction identification information for each of the transactions, and a program for execution.

  (6) According to one aspect of the present invention, a computer that verifies transaction identification information used in a block chain for guaranteeing the legitimacy of a transaction between a plurality of terminals connected to a network is connected to a computer that performs the transaction. A transaction identification information acquisition step for acquiring transaction identification information; an electronic signature acquisition step for acquiring the electronic signature of the trader; a calculation step for calculating a hash value of the electronic signature acquired by the electronic signature acquisition step; Based on the hash value calculated by the calculation step, a decryption step for decrypting the transaction identification information, a decryption information for the decryption step to decrypt the transaction identification information, and a trader identification information for identifying the trader. A determination step for determining whether or not they match, and a program to be executed.

  ADVANTAGE OF THE INVENTION According to this invention, the mechanism which improves the secrecy of the transaction identification information of the transaction between several terminals connected to a network can be provided.

It is a figure which shows an example of the network of 1st Embodiment. It is a figure which shows an example of the block chain in 1st Embodiment. It is a figure which shows an example of a structure of the production | generation apparatus which concerns on 1st Embodiment. It is a flowchart which shows an example of operation | movement of the production | generation apparatus which concerns on 1st Embodiment. It is a figure which shows an example of a structure of the verification apparatus which concerns on 2nd Embodiment. It is a flowchart which shows an example of operation | movement of the verification apparatus which concerns on 2nd Embodiment. It is a figure which shows an example of the block chain which concerns on a modification.

[First Embodiment]
The first embodiment of the present invention will be described below with reference to the drawings.

<About network configuration>
First, with reference to FIG. 1, the structure and outline | summary of the network NW of 1st Embodiment are demonstrated.
FIG. 1 is a diagram illustrating an example of a network NW according to the first embodiment. A client terminal T (shown, client terminal T1 to client terminal T10) and a server SA (shown, server SA1 to server SA4) are connected to the network NW shown in FIG. In the following description, when the client terminals T1 to T10 are not distinguished, they are collectively referred to as the client terminal T. When the servers SA1 to SA4 are not distinguished, they are collectively referred to as a server SA.

  The network NW includes, for example, the Internet, a dedicated communication line (for example, a CATV (Community Antenna Television) line), a mobile communication network (including a base station), a gateway, and the like. The server SA is, for example, a server computer having a Web server function. The client terminal T is, for example, a personal computer, a communication terminal device (such as a smartphone or a tablet), or the like.

  The client terminal T and the server SA perform virtual transaction communication via the network NW. Virtual transaction communication is communication in which traders who conduct a transaction to be traded perform the transaction via the network NW. The virtual transaction communication is performed by, for example, a Peer to Peer (hereinafter, P2P) communication method. The transaction object is, for example, a virtual currency, a certificate of a copyrighted work, or the like. The example shown in FIG. 1, client terminals T1 to T7, and servers SA1 to SA3 perform virtual transaction communication as nodes N1 to N10, respectively.

Hereinafter, the case where the transaction object of the transaction performed by the virtual transaction communication is a virtual currency (for example, bit coin) will be described. The virtual currency functions as a digital currency that can be exchanged without going through a financial institution when traders trade with each other through virtual transaction communication.
Here, it is required that the virtual currency is not used twice and is not generated by falsification of data. These can be realized by a distributed ledger technology using a block chain that guarantees the origin of the virtual currency to be traded.

<About blockchain>
Hereinafter, the block chain will be described with reference to the drawings.
FIG. 2 is a diagram illustrating an example of a block chain in the first embodiment.
The virtual currency transaction is performed by broadcasting transaction data (hereinafter referred to as a transaction) of a transaction performed by a certain trader to all nodes N (traders) by virtual trade communication. The transaction includes information for identifying the trader of the transaction (hereinafter, personal ID) and information indicating the amount of virtual currency to be traded. The block includes a hash value of the block immediately before the block, information indicating a plurality of transactions collected in the block, and a nonce value. The nonce value is a value calculated by the creator of the block, and is a value in which the hash value of the block is not more than a preset value. The creator of the block calculates the nonce value using the client terminal T or the server SA connected by virtual transaction communication, and creates a block.

With the mechanism described above, all traders can refer to the virtual currency transaction by referring to the block. In other words, in the virtual currency transaction using the block chain, it may be difficult to increase the confidentiality of the transaction history of the transaction.
The generation device 1 according to the present embodiment supports increasing the confidentiality of the transaction of the transaction by generating an anonymous ID based on the personal ID of the transaction and using the anonymous ID for the transaction.
Hereinafter, a specific functional configuration of the generation device 1 will be described.

<Configuration of generating device>
FIG. 3 is a diagram illustrating an example of the configuration of the generation device 1 according to the first embodiment.
The generation device 1 is, for example, a device provided in a server SA or a client terminal T used by a trader for virtual currency transactions.
As illustrated in FIG. 3, the generation device 1 includes a control unit 100 and a storage unit 500. The storage unit 500 stores secret key information SK that is used by a trader for virtual currency transactions and is used for a public key cryptosystem. In addition, the storage unit 500 stores personal ID information PID indicating a trader's personal ID.

The control unit 100 includes a CPU (Central Processing Unit), a reception unit 110, a calculation unit 120, an electronic signature generation unit 130, an anonymous ID generation unit 140, a transaction information acquisition unit 150, and a transmission unit 160. Are provided as functional parts thereof.
The receiving unit 110 receives information (hereinafter, block information BK) indicating a block immediately before the block that is in an open state (hereinafter, the previous block) when a transaction is performed by virtual transaction communication. The block information BK includes a hash value, a nonce value, and information indicating a transaction of the block immediately before the previous block.
The calculation unit 120 calculates the hash value of the previous block (hereinafter, block hash value BHA) based on the block information BK received by the reception unit 110.

The electronic signature generation unit 130 generates an electronic signature of the block hash value BHA based on the block hash value BHA calculated by the calculation unit 120 and the secret key information SK.
The calculation unit 120 calculates a hash value (hereinafter, signature hash value SHA) of the electronic signature information DS based on information indicating the electronic signature generated by the electronic signature generation unit 130 (hereinafter, electronic signature information DS).
The anonymous ID generation unit 140 encrypts the personal ID information PID based on the signature hash value SHA calculated by the calculation unit 120, and generates anonymous ID information AID. Specifically, the anonymous ID generation unit 140 encrypts the personal ID information PID using the signature hash value SHA as common key information (hereinafter, common key information CK) of the common key cryptosystem, and generates anonymous ID information AID. . In other words, the signature hash value SHA is the common key information CK used when encrypting the personal ID information PID by the common encryption method.

The transaction information acquisition unit 150 acquires information (hereinafter referred to as transaction information TR) related to the transaction performed by the transaction. The transaction information acquisition unit 150 acquires, for example, an operation that is input to the server SA or the client terminal T used by the trader and that is related to a virtual currency transaction as the transaction information TR. The transaction information TR includes information indicating the remittance amount of the virtual currency and information indicating the personal ID of the remittance destination trader.
The transmission unit 160 transmits a transaction based on the anonymous ID information AID generated by the anonymous ID generation unit 140 and the transaction information TR to all the nodes N by virtual transaction communication. Specifically, the transmission unit 160 transmits a transaction including the anonymous ID indicated by the anonymous ID information AID, the remittance amount of the virtual currency indicated by the transaction information TR, and the personal ID of the remittance destination trader.

<Operation of generating device>
Hereinafter, the details of the operation of the generation apparatus 1 will be described with reference to the drawings.
FIG. 4 is a flowchart illustrating an example of the operation of the generation device 1 according to the first embodiment.
The receiving unit 110 receives the block information BK through virtual transaction communication (step S110). The calculating unit 120 calculates a block hash value BHA based on the block information BK received by the receiving unit 110 (step S120). The electronic signature generation unit 130 generates the electronic signature information DS based on the secret key information SK and the block hash value BHA (Step S130). The calculation unit 120 calculates a signature hash value SHA based on the digital signature information DS generated by the digital signature generation unit 130 (step S140). The anonymous ID generation unit 140 generates anonymous ID information AID based on the personal ID information PID and the signature hash value SHA (step S150). The transmission unit 160 transmits a transaction based on the transaction information TR and the anonymous ID information AID (step S160).

<Summary of First Embodiment>
As described above, the generation apparatus 1 of the present embodiment generates anonymous ID information AID based on the hash value of the previous block (in the example of the present embodiment, the block hash value BHA) and the personal ID information PID. To do. Here, the block hash value BHA is different for each block that is the previous block. Therefore, according to the generation device 1 of the present embodiment, it is possible to perform a transaction using a different anonymous ID for each transaction not included in the same block. That is, according to the generating apparatus 1 of the present embodiment, the trader can increase the confidentiality of the transaction by using the anonymous ID for the virtual currency transaction.

[Second Embodiment]
Hereinafter, a second embodiment according to an embodiment of the present invention will be described.
1st Embodiment demonstrated the production | generation apparatus 1 which produces | generates anonymous ID according to a transaction person's personal ID.
Here, when a trader conducts a transaction using an anonymous ID, the counterparty of the trader (the remittance trader) can verify whether or not the trader is a legitimate trader. Is preferred.
2nd Embodiment demonstrates the verification apparatus 2 which verifies whether a trader is a valid trader based on the anonymous ID which a trader uses, and electronic signature information DS.
In addition, about the structure similar to embodiment mentioned above, the same code | symbol is attached | subjected and description is abbreviate | omitted.

<Configuration of verification device>
Hereinafter, the configuration of the verification apparatus 2 will be described with reference to FIG.
FIG. 5 is a diagram illustrating an example of the configuration of the verification apparatus 2 according to the second embodiment.
The verification device 2 is, for example, a device provided in a server SA or a client terminal T used by a trading partner of an anonymous ID for a virtual currency transaction. In the following description, a trader who uses an anonymous ID is simply described as a trader, and a trade partner of the trader is described as a verifier.
As illustrated in FIG. 5, the verification device 2 includes a control unit 200. The control unit 200 includes a CPU, and includes an electronic signature information acquisition unit 210, an anonymous ID information acquisition unit 220, a personal ID information acquisition unit 230, a calculation unit 240, a decryption unit 250, and a determination unit 260. It is provided as a functional part.

The electronic signature information acquisition unit 210 acquires electronic signature information DS from the trader. Moreover, the anonymous ID information acquisition part 220 acquires anonymous ID information AID from a trader. Here, the trader and the verifier establish an encrypted communication path between the server SA and the client terminal T used for the transaction, respectively, and the electronic signature information DS and the anonymous ID information AID via the encrypted communication path. To get.
The personal ID information acquisition unit 230 acquires the personal ID information PID of the trader from the trader. Here, since the personal ID information PID is information that is known to the node N that performs virtual transaction communication, the personal ID information PID may be acquired using an encrypted communication path, or may be acquired through communication via the network NW. Good.

  The calculation unit 240 calculates a signature hash value SHA based on the electronic signature information DS acquired by the electronic signature information acquisition unit 210. The decryption unit 250 decrypts the anonymous ID information AID using the signature hash value SHA as the common key information CK of the common key cryptosystem, and generates decryption information DCD. Here, when the anonymous ID information AID is the personal ID information PID encrypted by the common key information CK (signature hash value SHA) generated by the generation device 1 described above, the decryption information DCD and the personal ID information PID Matches.

  The determination unit 260 determines whether or not the decryption information DCD generated by the decryption unit 250 matches the personal ID information PID acquired by the personal ID information acquisition unit 230. When the decryption information DCD and the personal ID information PID match, the determination unit 260 determines that the trader indicated by the anonymous ID is a trader who does not use an illegal personal ID (a legitimate trader). . Further, in the case where the decryption information DCD and the personal ID information PID do not match, the determination unit 260 indicates that the trader indicated by the anonymous ID is a trader (unauthorized trader) using an invalid personal ID. judge.

<Operation of verification device>
Hereinafter, details of the operation of the verification apparatus 2 will be described with reference to the drawings.
FIG. 6 is a flowchart showing an example of the operation of the verification apparatus 2 according to the second embodiment.
The electronic signature information acquisition unit 210 acquires the electronic signature information DS (step S210). The anonymous ID information acquisition unit 220 acquires anonymous ID information AID (step S220). The personal ID information acquisition unit 230 acquires the personal ID information PID of the trader (step S230). The calculation unit 240 calculates a signature hash value SHA of the electronic signature information DS (Step S240). The decryption unit 250 decrypts the anonymous ID information AID using the signature hash value SHA as the common key information CK, and generates decryption information DCD (step S250).

  The determination unit 260 determines whether or not the decrypted information DCD matches the personal ID information PID (step S260). When the decryption information DCD matches the personal ID information PID (step S260; YES), the determination unit 260 determines that the transaction is a valid transaction (step S270). Further, when the decryption information DCD and the personal ID information PID do not match (step S260; NO), the determination unit 260 determines that the trader is an unjust trader (step S280).

<Summary of Second Embodiment>
As described above, the verification device 2 according to the present embodiment determines whether or not the trader is a legitimate trader based on the electronic signature information DS and the anonymous ID information AID.
According to the verification device 2 of the present embodiment, the verifier verifies whether the trader is a legitimate trader based on the electronic signature information DS and the anonymous ID information AID, and performs a transaction with the trader. It can be carried out.
Further, according to the verification device 2 of the present embodiment, by using the electronic signature information DS generated by the generation device 1, the verifier can easily verify the trader.

[Modification]
Hereinafter, modified examples according to the first embodiment of the present invention will be described.
In the first embodiment, the case where the block chain is in one row has been described.
In the modification, a case where the block chain branches into an upper layer and a lower layer will be described.
In addition, about the structure similar to embodiment mentioned above, the same code | symbol is attached | subjected and description is abbreviate | omitted.

<About blockchain>
Hereinafter, a block chain according to a modification will be described with reference to the drawings.
FIG. 7 is a diagram illustrating an example of a block chain according to a modification.
Here, the block chain may branch into an upper chain and a lower chain according to the network NW structure.
As an example of the modification, a case where the block 61 and the block 62 are connected to the upper chain will be described. Further, between the block 61 and the block 62, the upper chain branches into a first lower chain and a second lower chain, and a block 71 and a block 72 are connected to the first lower chain, A block 81 is connected to the second lower chain.

  For example, when generating the anonymous ID included in the transaction of a block having a plurality of previous blocks (in this example, the block 62), the generating device 1 uses the plurality of blocks (in this example, the block as block information BK). 61, block 72, and block 81) are obtained. The generation device 1 calculates the block hash value BHA for each block information BK based on the acquired block information BK of the plurality of blocks, and generates anonymous ID information AID.

As described above, when a plurality of previous blocks exist, the generation device 1 according to the modification calculates the block hash value BHA of the block based on the block hash values BHA of the plurality of blocks.
Therefore, according to the generation device 1 of the modification, anonymous ID information AID can be generated even when there are a plurality of previous blocks.

  In addition, although the case where the transaction performed by virtual transaction communication is a transaction of virtual currency was demonstrated above, it is not restricted to this. The transaction performed by the virtual transaction communication may be a transaction of a copyrighted work, or a transaction of a guarantee for the expensive item accompanying the transaction of the expensive item or the like.

  In addition, each part with which the production | generation apparatus 1 in each said embodiment and the verification apparatus 2 are provided may be implement | achieved by dedicated hardware, and may be implement | achieved by memory and a microprocessor. Good.

  Each unit included in the generation device 1 and the verification device 2 includes a memory and a CPU (central processing unit), and a program for realizing the function of each unit included in the generation device 1 and the verification device 2 is loaded into the memory. The function may be realized by executing as described above.

  Further, a program for realizing the function of each unit included in the generation device 1 and the verification device 2 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed. Depending on the situation, the processing may be performed. Here, the “computer system” includes an OS and hardware such as peripheral devices.

Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW system is used.
The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” dynamically holds a program for a short time like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory in a computer system serving as a server or a client in that case, and a program that holds a program for a certain period of time are also included. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and appropriate modifications may be made without departing from the spirit of the present invention. it can. You may combine the structure as described in each embodiment mentioned above.

DESCRIPTION OF SYMBOLS 1 ... Generation apparatus, 2 ... Verification apparatus, 100 ... Control part, 110 ... Reception part, 120 ... Calculation part, 130 ... Digital signature generation part, 140 ... Generation part, 150 ... Transaction information acquisition part, 160 ... Transmission part, 200 ... Control unit 210 ... Electronic signature information acquisition unit 220 ... Anonymous ID information acquisition unit 230 ... Personal ID information acquisition unit 240 ... Calculation unit 250 ... Decryption unit 260 ... Determination unit 500 ... Storage unit AID ... Anonymous ID information, PID ... personal ID information, BHA ... block hash value, SHA ... signature hash value, BK ... block information, DS ... digital signature information, SK ... private key information, CK ... common key information, TR ... transaction information, DCD: Decoding information, SA, SA1, SA2, SA3, SA4 ... Server, T, T1, T2, T3, T4, T5, T6, T7, T10 ... Client terminal

Claims (6)

A generation device that generates transaction identification information used in a block chain for guaranteeing the legitimacy of a transaction between a plurality of terminals connected to a network,
A calculation unit that calculates, as a block hash value, a hash value of a block immediately preceding a block in an open state among a plurality of blocks included in the block chain;
Transaction identification information used for the transaction is based on the block hash value calculated by the calculation unit, secret key information different for each trader performing the transaction, and trader identification information different for each trader. An identification information generation unit to generate,
A generating device comprising: An electronic signature generation unit that generates an electronic signature based on the block hash value calculated by the calculation unit and the secret key information;
The calculation unit includes:
Calculating a hash value of the electronic signature generated by the electronic signature generation unit as a signature hash value;
The identification information generation unit
Generating the transaction identification information based on the signature hash value and the transaction identification information;
The generation device according to claim 1. The calculation unit includes:
The generation device according to claim 1, wherein when there are a plurality of blocks immediately preceding the open block, the block hash value is calculated based on each hash value of the plurality of blocks. A verification device for verifying transaction identification information used in a block chain for guaranteeing the validity of a transaction between a plurality of terminals connected to a network,
A trader identification information acquisition unit for acquiring transaction identification information used when a trader performs the transaction;
An electronic signature acquisition unit for acquiring an electronic signature of the trader;
A calculation unit that calculates a hash value of the electronic signature acquired by the electronic signature acquisition unit;
A decryption unit that decrypts the transaction identification information based on the hash value calculated by the calculation unit;
A determination unit that determines whether or not the decryption information obtained by decrypting the transaction identification information by the decryption unit matches the trader identification information that identifies the trader;
A verification apparatus comprising: A computer that generates transaction identification information used in a block chain for ensuring the validity of a transaction between a plurality of terminals connected to a network,
A calculation step of calculating a hash value of a block immediately before a block in an open state among a plurality of blocks included in the block chain as a block hash value;
Based on the block hash value calculated by the calculating step, secret key information different for each trader performing the transaction, and trader identification information different for each trader, transaction identification information used for the transaction is obtained. An identification information generation step to generate,
A program to be executed. A computer that verifies transaction identification information used in a block chain for ensuring the validity of a transaction between a plurality of terminals connected to a network,
A transaction identification information acquisition step of acquiring transaction identification information of a trader performing the transaction;
An electronic signature acquisition step of acquiring an electronic signature of the trader;
A calculation step of calculating a hash value of the electronic signature acquired by the electronic signature acquisition step;
A decrypting step of decrypting the transaction identification information based on the hash value calculated by the calculating step;
A determination step for determining whether or not the decryption information for decrypting the transaction identification information and the trader identification information for identifying the trader match in the decryption step;
The program to be executed.

Images