JP6719410B2 - Generation device, verification device, and program - Google Patents

Description

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

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

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 a trade. Here, it is preferable that the identification information of the trader is anonymous in order to increase the confidentiality of the trade of the trader.
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 increasing the confidentiality of trader identification information of a transaction between a plurality of terminals connected to a network.

(1) One aspect of the present invention is a generation device that generates anonymous trader 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 before an open block among a plurality of blocks included in a chain, the block hash value calculated by the calculation unit, and the transaction. Based on the secret key information that is different for each trader to perform, a digital signature generation unit that generates a digital signature of the block hash value, and a signature hash value calculated based on the digital signature generated by the digital signature generation unit. An anonymous trader identification information generation unit that generates anonymous trader identification information by encrypting different trader identification information for each trader based on the generation device.

(2) One aspect of the present invention, in the generator according to the above (1), before Symbol calculating unit calculates a hash value of the digital signature which the electronic signature generation unit generates the signature hash value s.

(3) In one aspect of the present invention, in the generation device according to (1) or (2), when the calculation unit includes a plurality of blocks immediately preceding the block in the open state, the plurality of the plurality of blocks are included. 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 for verifying anonymous trader identification information used in a block chain for ensuring the validity of a transaction between a plurality of terminals connected to a network, wherein the transaction and the electronic signature acquisition unit that acquires the electronic signature of the transaction who performs the transaction identification information used in the transaction user performs the transaction is encrypted on the basis of the signature hash value calculated on the basis of the electronic signature Anonymous trader identification information acquisition unit that acquires the anonymous trader identification information generated by the above, a calculation unit that calculates a hash value of the electronic signature acquired by the electronic signature acquisition unit, and the calculation unit calculates Based on a hash value, a decryption unit that decrypts the anonymous trader identification information , decryption information obtained by the decryption unit that decrypts the anonymous trader identification information, and trader identification information that identifies the trader. The verification device includes a determination unit that determines whether or not they match.

(5) One aspect of the present invention is a computer that generates anonymous trader identification information used in a blockchain for guaranteeing the legitimacy of a transaction between a plurality of terminals connected to a network, and is included in the blockchain. Of a plurality of blocks to be opened, a calculation step of calculating a hash value of a block immediately before an open block as a block hash value, the block hash value calculated in the calculation step, and a trader who conducts the transaction on the basis different and secret key information for each, and the electronic signature generation step of generating an electronic signature of the block hash value, based on the signature hash value the digital signature generating step is calculated on the basis of the digital signature to generate, A program for executing an anonymous trader identification information generating step of generating anonymous trader identification information by encrypting different trader identification information for each trader .

(6) One aspect of the present invention is a transaction for performing the transaction to a computer for verifying anonymous trader identification information used in a block chain for guaranteeing the validity of the transaction between a plurality of terminals connected to a network. and the electronic signature acquiring the electronic signature of the person, generated by the transaction identification information used in the transaction user performs the transaction is encrypted on the basis of the signature hash value calculated on the basis of the electronic signature and anonymous transaction identification information acquiring step of acquiring the anonymous transaction identification information, and calculating a hash value of the digital signature which the electronic signature acquisition step acquires, the hash value the calculating step calculates or based on a decoding step of decoding the anonymous transaction identification information, and decoding information about a result of said decoding step is decoding the anonymous transaction identification information, and transaction identification information for identifying the trader matches It is a determination step for determining whether or not the program is executed.

According to the present invention, it is possible to provide a mechanism for increasing the confidentiality of trader identification information of a transaction between a plurality of terminals connected to a network.

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. 6 is a flowchart showing an example of the operation of the generation device according to the first embodiment. It is a figure which shows an example of a structure of the verification apparatus which concerns on 2nd Embodiment. 9 is a flowchart showing an example of the operation of the verification device according to the second embodiment. It is a figure which shows an example of the block chain which concerns on a modification.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

<About network configuration>
First, the configuration and outline of the network NW of the first embodiment will be described with reference to FIG.
FIG. 1 is a diagram illustrating an example of the network NW according to the first embodiment. A client terminal T (illustrated, client terminal T1 to client terminal T10) and a server SA (illustrated, server SA1 to server SA4) are connected to the network NW illustrated 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 the server SA.

The network NW includes, for example, the Internet, a dedicated communication line (for example, CATV (Community Antenna Television) line), a mobile communication network (including a base station, etc.), 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 (smartphone, tablet, etc.), or the like.

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

Hereinafter, a case where the transaction target of the transaction performed by the virtual transaction communication is virtual currency (for example, bit coin) will be described. Virtual currencies function as digital currencies that can be exchanged without the intervention of a financial institution by trading between traders through virtual transaction communication.
Here, it is required that the virtual currency is not used twice and that it is not generated by falsification of data. These can be realized by the distributed ledger technology using a block chain that guarantees the source 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 showing an example of a block chain in the first embodiment.
Transaction of virtual currency is performed by transmitting transaction data (hereinafter, transaction) of a transaction performed by a certain trader to all nodes N (traders) by virtual transaction 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 preceding the block, information indicating a plurality of transactions grouped in the block, and a nonce value. The nonce value is a value calculated by the creator of the block, and is a value at which the hash value of the block is equal to or less 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 the block.

With the above-mentioned mechanism, all traders can refer to the virtual currency transaction by referring to the block. In other words, it is sometimes difficult to increase the confidentiality of the transaction history of the trader in the virtual currency transaction using the block chain.
The generation device 1 according to the present embodiment generates an anonymous ID based on the individual ID of the trader and uses the anonymous ID for the transaction to support the confidentiality of the transaction of the trader.
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 used by a trader for trading virtual currency or a client terminal T.
As shown 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 key information used by a trader for trading virtual currency and that is used for public key cryptography. Further, the storage unit 500 stores the personal ID information PID indicating the personal ID of the trader.

The control unit 100 includes a CPU (Central Processing Unit), and has 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. And are provided as its functional units.
The receiving unit 110 receives, through virtual transaction communication, information (hereinafter, block information BK) indicating a block (hereinafter, “previous block”) immediately preceding a block that is in an open state when a transaction is performed. The block information BK includes a hash value of the block immediately preceding the previous block, a nonce value, and information indicating a transaction.
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 digital signature information DS based on information (hereinafter, digital signature information DS) indicating the digital signature generated by the digital signature generation unit 130.
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 the anonymous ID information AID. Specifically, the anonymous ID generation unit 140 encrypts the personal ID information PID using the signature hash value SHA as the common key information of the common key cryptosystem (hereinafter, common key information CK) to generate the anonymous ID information AID. .. In other words, the signature hash value SHA is the common key information CK used when the personal ID information PID is encrypted by the common encryption method.

The transaction information acquisition unit 150 acquires information (hereinafter, transaction information TR) related to the transaction performed by the trader. The transaction information acquisition unit 150 acquires, as transaction information TR, an operation that is input to the server SA or the client terminal T used by a trader and is related to a transaction of virtual currency. The transaction information TR includes information indicating the remittance amount of 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 amount of virtual currency indicated by the transaction information TR, and the individual ID of the remittance destination trader.

<Operation of generating device>
Hereinafter, the details of the operation of the generation device 1 will be described with reference to the drawings.
FIG. 4 is a flowchart showing an example of the operation of the generation device 1 according to the first embodiment.
The receiving unit 110 receives the block information BK by virtual transaction communication (step S110). The calculation unit 120 calculates the block hash value BHA based on the block information BK received by the reception 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 the 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 the transaction based on the transaction information TR and the anonymous ID information AID (step S160).

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

[Second Embodiment]
The second embodiment according to the embodiment of the present invention will be described below.
1st Embodiment demonstrated the production|generation apparatus 1 which produces|generates an anonymous ID according to a trader's individual ID.
Here, when a trader conducts a transaction using an anonymous ID, the trading partner of the trader (the remittance trader) can verify whether or not the trader is a valid trader. Is preferred.
In the second embodiment, a verification device 2 that verifies whether or not the trader is a valid trader based on the anonymous ID used by the trader and the electronic signature information DS will be described.
The same components as those in the above-described embodiment are designated by the same reference numerals and description thereof will be omitted.

<Configuration of verification device>
The configuration of the verification device 2 will be described below with reference to FIG.
FIG. 5: is a figure which shows an example of a structure of the verification apparatus 2 which concerns on 2nd Embodiment.
The verification device 2 is, for example, a device provided to a server SA used by a trading partner of a trader who uses an anonymous ID for trading virtual currency, or a client terminal T. In the following description, a trader using an anonymous ID will be simply referred to as a trader, and a trader of the trader will be referred to as a verifier.
As shown 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 the functional unit.

The electronic signature information acquisition unit 210 acquires the electronic signature information DS from the trader. Further, the anonymous ID information acquisition unit 220 acquires the anonymous ID information AID from the trader. Here, the trader and the verifier build an encrypted communication path between the server SA and the client terminal T used for the transaction, 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 well known to the node N that performs virtual transaction communication, it may be acquired using an encrypted communication path or may be acquired by communication via the network NW. Good.

The calculation unit 240 calculates the 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 by using the signature hash value SHA as the common key information CK of the common key cryptosystem, and generates the 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 And match.

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

<Operation of verification device>
Hereinafter, the details of the operation of the verification device 2 will be described with reference to the drawings.
FIG. 6 is a flowchart showing an example of the operation of the verification device 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 the 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 calculator 240 calculates the 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 the decryption information DCD and the personal ID information PID match (step S260). When the decryption information DCD and the personal ID information PID match (step S260; YES), the determination unit 260 determines that the trader is a valid trader (step S270). 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 of the present embodiment determines whether or not the trader is a valid 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 transactor is a legitimate transactor based on the electronic signature information DS and the anonymous ID information AID, and transacts with the transactor. It can be carried out.
Further, according to the verification device 2 of this embodiment, the verifier can easily verify the trader by using the electronic signature information DS generated by the generation device 1.

[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 chains are in a single 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.
The same components as those in the above-described embodiment are designated by the same reference numerals and description thereof will be omitted.

<About blockchain>
Hereinafter, a block chain according to a modification will be described with reference to the drawings.
FIG. 7 is a diagram showing an example of a block chain according to a modification.
Here, the block chain may be branched into an upper chain and a lower chain according to the network NW structure.
In an example of a 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 the block 71 and the block 72 are connected to the first lower chain, The block 81 is connected to the second lower chain.

For example, when generating the anonymous ID included in a transaction of a block having a plurality of previous blocks (block 62 in this example), the generation device 1 uses the plurality of blocks (blocks in this example as block information BK of the previous block. 61, block 72, and block 81) block information BK is acquired. 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 the anonymous ID information AID.

As described above, when there are a plurality of previous blocks, the generation device 1 of the modified example 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, the 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 may be a transaction of a guarantee certificate of the high-priced article accompanying the transaction of the high-priced article.

The units included in the generation device 1 and the verification device 2 in each of the above-described embodiments may be realized by dedicated hardware, or may be realized by a memory and a microprocessor. Good.

Each unit included in the generation device 1 and the verification device 2 is configured by a memory and a CPU (central processing unit), and a program for realizing the functions of each unit included in the generation device 1 and the verification device 2 is loaded into the memory. Then, the function may be realized by executing it.

In addition, a program for realizing the functions of each unit included in the generation device 1 and the verification device 2 is recorded in a computer-readable recording medium, and the program recorded in this recording medium is read into a computer system and executed. You may process by this. The “computer system” mentioned here includes an OS and hardware such as peripheral devices.

Further, the “computer system” also includes a homepage providing environment (or display environment) if a WWW system is used.
The "computer-readable recording medium" refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, a CD-ROM, or a storage device such as a hard disk built in a computer system. Further, the "computer-readable recording medium" means that a program is dynamically held for a short time like a communication line when transmitting the program through 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 that serves as a server or a client in that case, which holds a program for a certain period of time, is also included. Further, the program may be for realizing a part of the above-described functions, and may be a program for realizing the above-mentioned functions in combination with a program already recorded in the computer system.

Although the embodiment of the present invention has been described in detail above with reference to the drawings, 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. The configurations described in the above embodiments may be combined.

DESCRIPTION OF SYMBOLS 1... Generation device, 2... Verification device, 100... Control part, 110... Reception part, 120... Calculation part, 130... Electronic 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... Electronic signature information, SK... Secret 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 for generating anonymous trader identification information used in a block chain for guaranteeing the validity 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 that is one block before the block that is in an open state among a plurality of blocks included in the block chain.
An electronic signature generation unit that generates an electronic signature of the block hash value based on the block hash value calculated by the calculation unit and secret key information that is different for each trader performing the transaction ,
Anonymous transaction that generates anonymous trader identification information by encrypting different trader identification information for each trader based on a signature hash value calculated based on the electronic signature generated by the electronic signature generation unit Person identification information generation unit,
A generator comprising. Before Symbol calculating unit,
The generation device according to claim 1, wherein a hash value of the digital signature generated by the digital signature generation unit is calculated as a signature hash value. The calculation unit,
The generation device according to claim 1, wherein when there are a plurality of blocks immediately preceding the block in the open state, the block hash value is calculated based on each hash value of the plurality of blocks. A verification device for verifying anonymous trader identification information used in a block chain for ensuring the validity of a transaction between a plurality of terminals connected to a network,
An electronic signature acquisition unit for acquiring an electronic signature of a trader who conducts the transaction,
Anonymous trader the trader to get an anonymous transaction identification information generated by being encrypted based on a signature hash value transaction identification information is calculated based on the digital signature used in performing the transaction An identification information acquisition unit,
A calculation unit that calculates a hash value of the digital signature acquired by the digital signature acquisition unit;
A decryption unit that decrypts the anonymous trader identification information based on the hash value calculated by the calculation unit,
Decryption information as a result of the decryption unit decrypting the anonymous trader identification information , and a determination unit that determines whether or not the trader identification information that identifies the trader,
A verification device comprising. A computer that generates anonymous trader identification information used in a blockchain for guaranteeing the legitimacy of transactions between a plurality of terminals connected to a network,
A calculation step of calculating, as a block hash value, a hash value of a block immediately before the block in the open state among the plurality of blocks included in the block chain;
And said block hash value the calculating step calculates, on the basis of trading on the different secret key information for each transaction who perform a digital signature generating step of generating an electronic signature of the block hash value,
Anonymous transaction that generates anonymous trader identification information by encrypting different trader identification information for each trader based on a signature hash value calculated based on the digital signature generated by the digital signature generation step. Person identification information generation step,
A program to run. A computer that verifies anonymous trader identification information used in the blockchain to ensure the validity of transactions between multiple terminals connected to the network,
An electronic signature acquisition step of acquiring an electronic signature of a trader who conducts the transaction,
Anonymous trader the trader to get an anonymous transaction identification information generated by being encrypted based on a signature hash value transaction identification information is calculated based on the digital signature used in performing the transaction Identification information acquisition step,
A calculation step of calculating a hash value of the digital signature acquired by the digital signature acquisition step;
A decryption step of decrypting the anonymous trader identification information based on the hash value calculated by the calculation step;
Decoding information as a result of the decryption step of decrypting the anonymous trader identification information , and a determination step of determining whether or not the trader identification information for identifying the trader matches,
The program to run.

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