WO2021134876A1 - Blockchain-based transaction data obfuscation method, and related device - Google Patents

Abstract

Disclosed is a blockchain-based transaction data obfuscation method. The method comprises: receiving an obfuscation request sent by a supplier node device for a target confidential transaction; obfuscating the target confidential transaction by using a target random number to obtain an obfuscated transaction; acquiring a random mapping parameter and a signed first challenge parameter from a regulator node device; performing product proving and power proving; and outputting the obfuscated transaction, a product proving result and a power proving result. Further provided is a related device. According to the present invention, anonymity of a transaction can be realized, and regulation of transaction data can also be realized.

Description

Block chain-based transaction data obfuscation method and related equipment

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office on December 31, 2019, the application number is 201911416640.X, and the invention title is "Blockchain-based transaction data obfuscation method and related equipment", and its entire content Incorporated in this application by reference.

Technical field

The present invention relates to the technical field of block chains, in particular to a method and related equipment for obfuscation of transaction data based on block chains.

Background technique

In blockchain technology, in order to ensure that the transaction data cannot be tampered with, the transaction data is usually uploaded and added to the blockchain, but this will cause any node in the blockchain network to obtain the transaction data, making the transaction The data loses its confidentiality. At the same time, any node can view both parties of the transaction data, and the anonymity of the transaction cannot be realized.

Therefore, how to improve the confidentiality of transaction data and at the same time realize the anonymity of transactions is an urgent technical problem to be solved.

Summary of the invention

In view of the above, it is necessary to provide a blockchain-based transaction data obfuscation method and related equipment, which can improve the confidentiality of transaction data, realize the anonymity of transactions, and at the same time, realize the supervision of transaction data.

The first aspect of the present invention provides a blockchain-based transaction data obfuscation method, which is applied to obfuscate service provider node equipment, and the method includes:

Receiving an obfuscation request sent by a supplier node device for a target confidential transaction, where the obfuscation request carries the target random number;

Use the target random number to confuse the target confidential transaction to obtain a confused transaction;

Obtain random mapping parameters and signed first challenge parameters from the node device of the regulatory agency;

Generating a plurality of first random numbers, calculating a second challenge parameter according to the plurality of first random numbers and the first challenge parameter, and calculating a third challenge parameter according to the second challenge parameter;

Calculate the first intermediate variable and the second intermediate variable;

Perform product proof according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable;

Performing a power proof according to the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable;

Output the result of the confusing transaction, the result of the product proof, and the result of the power proof.

In a possible implementation manner, the using the target random number to obfuscate the target confidential transaction, and obtaining the obfuscated transaction includes:

Use the following formula to obfuscate the target confidential transaction using the target random number to obtain a confused transaction. The formula is:

Wherein, the C′ _i is the obfuscated transaction, C _π(i) is the target confidential transaction, h is a system parameter, and r is the target random number.

In a possible implementation manner, the second challenge parameter y=Hash(C _B1 ||...||C _Bu ), where,

g ₁ , g ₂ ,..., g _v , h are all system parameters, {s ₁ ,..., s _u } are the u first random numbers, x is the first challenge parameter, and π(i) is For the random mapping parameter, the range of π(i) is [1, k], and C _Bi is the third intermediate variable.

In a possible implementation manner, the third challenge parameter z=Hash(C _B1 ||...||C _Bu ||y), the first intermediate variable

among them,

The second intermediate variable

Among them, ρ _i is the second random number.

In a possible implementation manner, the performing product proof according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable includes:

The product proof formula is used to perform product proof according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable, and the product proof formula is as follows:

In a possible implementation manner, the performing a power proof based on the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable includes:

Using the power proof formula, the power proof is performed according to the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable, wherein the power proof formula is as follows:

Among them, the

Is the target confidential transaction,

For the said obfuscated transaction.

The second aspect of the present invention provides a blockchain-based transaction data obfuscation method, which is applied to a node device of a regulatory agency, and the method includes:

Generate random mapping parameters;

Calculating the first challenge parameter according to the random mapping parameter;

Use the private key to sign the first challenge parameter;

The signed first challenge parameter and the random mapping parameter are sent to the obfuscated service provider node device, so that the obfuscated service provider node device can use the signed first challenge parameter and the random mapping parameter pair The target confidential transaction performs a supervisable proof of confusion.

In a possible implementation manner, the method further includes:

Saving the signed first challenge parameter and the random mapping parameter;

Obtain the target confidential transaction sent by the supplier node device, and use the signed first challenge parameter and the random mapping parameter to supervise the target confidential transaction.

A third aspect of the present invention provides a blockchain node device, the blockchain node device includes a memory and a processor, the memory stores blockchain transaction data that can run on the processor to prove supervision The downloading program of the method, when the downloading program of the blockchain transaction data certification supervision method is executed by the processor, realizes the transaction data obfuscation method based on the blockchain.

A fourth aspect of the present invention provides a computer-readable storage medium, the computer-readable storage medium stores a download program for the blockchain transaction data certification and supervision method, and the download program for the blockchain transaction data certification and supervision method It can be executed by one or more processors to implement the blockchain-based transaction data obfuscation method.

In the above technical solution, the target confidential transaction is an encrypted transaction. Only both parties to the transaction can decrypt the amount in the target confidential transaction, which protects the transaction privacy from being leaked. At the same time, by obfuscating the target confidential transaction, the target confidential transaction can be confused with the target. The obfuscated transaction equivalent to the confidential transaction realizes the anonymity of the transaction. At the same time, the required parameters are obtained from the node device of the supervisory authority, which is convenient for the supervisor to supervise the transaction data on the chain.

Description of the drawings

FIG. 1 is a flowchart of a preferred embodiment of a method for obfuscation of transaction data based on blockchain disclosed in the present invention.

Fig. 2 is a flowchart of another preferred embodiment of a block chain-based transaction data obfuscation method disclosed in the present invention.

Fig. 3 is a functional block diagram of a preferred embodiment of a transaction data obfuscation device disclosed in the present invention.

Fig. 4 is a functional module diagram of another preferred embodiment of a transaction data obfuscation device disclosed in the present invention.

FIG. 5 is a schematic structural diagram of a blockchain node device according to a preferred embodiment of the method for obfuscation of transaction data based on the blockchain according to the present invention.

Detailed ways

In order to make the objectives, technical solutions, and advantages of the present invention clearer, the following further describes the present invention in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not used to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

The terms "first" and "second" in the description and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific sequence or sequence, nor can they be understood as instructions or Imply its relative importance or implicitly indicate the number of technical features indicated. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments described herein can be implemented in an order other than the content illustrated or described here, and the features defined as "first" and "second" can be At least one of this feature is explicitly or implicitly included.

In addition, the terms "including" and "having" and any variations of them are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those clearly listed. Those steps or units may include other steps or units that are not clearly listed or are inherent to these processes, methods, products, or equipment.

In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on what can be achieved by a person of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be achieved, it should be considered that such a combination of technical solutions does not exist. , Is not within the protection scope of the present invention.

Please refer to FIG. 1. FIG. 1 is a flowchart of a preferred embodiment of a method for obfuscation of transaction data based on blockchain disclosed in the present invention.

Wherein, the block chain-based transaction data obfuscation method is applied to obfuscate the service provider node equipment, and the block chain-based transaction data obfuscation method specifically includes the following steps. According to different needs, the steps in the flowchart The order can be changed, and some steps can be omitted.

S11. Receive the obfuscation request sent by the supplier node device for the target confidential transaction.

Wherein, the obfuscation request carries a target random number, and the target random number is used to obfuscate the original transaction on the blockchain. Wherein, the target confidential transaction may be one or multiple.

The supplier node device needs to perform a series of operations in advance before sending the obfuscation request.

For example, suppose the target confidential transaction

The supplier node device sends a transaction

On the chain, with Gas, where g and h are system parameters, x ₁ is the transaction amount, r ₁ is a random number, and Gas represents the number of times the transaction can be confused.

First, the supplier node device selects the target random number r ₂ and calculates the result after confusion

And after the confusion, the specific value of Gas' and Gas' depends on the setting of the specific parameters of the system. Assuming that the initial value of Gas is 3, it will be reduced by 1 each time it is confused. The supplier node device calculates hash ₁ = Hash(C′ ₁ ||Gas′), and maps _{hash 1 to}

for

among them,

Is the value range of the transaction amount,

Is the transaction amount, and calculate

And provide proof: Chaum-Pedersen(C′ ₁ ,C _Hash ),

Among them, C _Hash is an intermediate variable, and Chaum-Pedersen (C′ ₁ , C _Hash ) proves that the supplier node device can expose C′ ₁ , which means that the supplier node device is the owner of the target confidential transaction By;

It is proved that the Gas after this round of confusion is the correct Gas value that can be accepted by the supplier's node equipment.

After that, the supplier node device can carry

The obfuscation request of is sent to the obfuscated service provider node device to trigger the obfuscated service provider node device to obfuscate the target confidential transaction.

Among them, Chaum-Pedersen proves to belong to the prior art, so I won't repeat it here.

S12. Use the target random number to obfuscate the target confidential transaction to obtain a confused transaction.

Specifically, the use of the target random number to obfuscate the target confidential transaction to obtain the obfuscated transaction includes:

Use the following formula to obfuscate the target confidential transaction using the target random number to obtain a confused transaction. The formula is:

C′ _i = h ^r C _π(i)

Wherein, the C′ _i is the obfuscated transaction, C _π(i) is the target confidential transaction, h is the system parameter, r is the target random number, and π(i) is within the range of [1,k] The random mapping parameters.

Wherein, the target confidential transaction is equivalent to the obfuscated transaction.

S13. Obtain the random mapping parameter and the signed first challenge parameter from the regulatory agency node device.

Among them, after the obfuscated service provider node device calculates the obfuscated transaction, it also needs to perform obfuscation proof.

In order to facilitate the supervision of the transaction by the supervisor, the random mapping parameter and the signed first challenge parameter can be obtained in advance from the node device of the supervisory authority, where the random mapping parameter π(i) falls within the range of [1, k] , {Π(1),π(2),...,π(k)} is a rearrangement of {1,2,...,k}.

Wherein, the first challenge parameter x=Hash(C _A1 ||...||C _Au ),

g ₁ , g ₂ ,..., g _v , h are all system parameters, and {r _A1 ,..., r _Au } are u random variables.

After the regulatory agency node device generates the first challenge parameter x, it can use the private key to sign the first challenge parameter x and send it to the obfuscated service provider node device.

S14. Generate a plurality of first random numbers, calculate a second challenge parameter according to the plurality of first random numbers and the first challenge parameter, and calculate a third challenge parameter according to the second challenge parameter.

Wherein, the second challenge parameter y=Hash(C _B1 ||...||C _Bu ), where,

g ₁ , g ₂ ,..., g _v , h are all system parameters, {s ₁ ,..., s _u } are the u first random numbers, x is the first challenge parameter, and π(i) is For the random mapping parameter, the range of π(i) is [1, k], and C _Bi is the third intermediate variable.

Wherein, the third challenge parameter z=Hash(C _B1 ||...||C _Bu ||y), the first intermediate variable

among them,

The second intermediate variable

Among them, ρ _i is the second random number.

S15. Calculate the first intermediate variable and the second intermediate variable.

Wherein, the first intermediate variable is

The second intermediate variable is

Wherein, ρ _i is a random number generated by the obfuscated service provider node device itself.

S16. Perform product proof according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable.

Specifically, the performing product proof according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable includes:

The product proof formula is used to perform product proof according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable, and the product proof formula is as follows:

Among them, other intermediate variables can also be used in the specific proof method of the product proof, and the specific method of the product proof belongs to the existing technology, and will not be repeated here. The above product proof can be used to prove that the obfuscated service provider node device has found a random obfuscation π(i), and prove that the order before and after the obfuscation is disturbed.

S17. Perform a power proof based on the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable.

Specifically, the performing the exponentiation proof according to the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable includes:

Using the power proof formula, the power proof is performed according to the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable, wherein the power proof formula is as follows:

Among them, the

Is the target confidential transaction,

For the said obfuscated transaction.

Among them, other intermediate variables can also be used in the specific proof method of the power proof, and the specific method of the power proof belongs to the existing technology, and will not be repeated here. The above proof of power can be used to prove that the π(i) in the power proof and the π(i) used in the product proof are the same π(i), which proves that the method of confusion is the same.

Among them, since the random mapping parameters and the signed first challenge parameter are obtained from the regulatory agency node device, the random mapping parameter obtained from the regulatory agency node device and the signed first challenge parameter are used to perform a provable confusion algorithm It can be called a verifiable shuffle with multi-regulators. Subsequent regulatory agency node devices can use their own stored random mapping parameters and signed first challenge parameters to track and supervise the transactions that need to be confused.

S18. Output the confusion transaction, the result of the product proof, and the result of the power proof.

Optionally, it can also output the relevant parameters and certifications provided by the above-mentioned supplier node equipment, such as output

In the method flow described in Figure 1, the target confidential transaction is an encrypted transaction. Only both parties to the transaction can decrypt the amount in the target confidential transaction, which protects transaction privacy from being leaked. At the same time, the target confidential transaction is obfuscated. The obfuscated transaction equivalent to the target confidential transaction realizes the anonymity of the transaction. At the same time, the required parameters are obtained from the node device of the supervisory authority, so that the supervisor can subsequently supervise the transaction data on the chain.

Please refer to FIG. 2, which is a flowchart of another preferred embodiment of a block chain-based transaction data obfuscation method disclosed in the present invention.

Wherein, the block chain-based transaction data obfuscation method is applied to the node equipment of the regulatory agency, and the block chain-based transaction data obfuscation method specifically includes the following steps. According to different needs, the order of the steps in the flowchart can be Change, some steps can be omitted.

S21: Generate random mapping parameters.

Among them, the regulatory agency node device can randomly select a random mapping parameter π(i), where the random mapping parameter π(i) belongs to the range of [1, k], {π(1), π(2),... ,π(k)} is the rearrangement of {1,2,...,k}.

S22. Calculate a first challenge parameter according to the random mapping parameter.

The regulatory agency node device may calculate the first challenge parameter according to the random mapping parameter.

Specifically, it can be calculated

x=Hash(C _A1 ||...||C _Au ),

Among them, g ₁ , g ₂ ,..., g _v , h are all system parameters, {r _A1 ,..., r _Au } are u random variables, and x is the first challenge parameter.

S23. Use the private key to sign the first challenge parameter.

The supervisory authority node device may use the private key to sign the first challenge parameter, and save the signature locally.

S24. Send the signed first challenge parameter and the random mapping parameter to the obfuscated service provider node device, so that the obfuscated service provider node device can use the signed first challenge parameter and the random mapping The parameters provide a supervisable proof of confusion for the target confidential transaction.

Wherein, the regulatory agency node device may send the signed first challenge parameter and the random mapping parameter to the obfuscated service provider node device after generating the random mapping parameter and the signed first challenge parameter. In this way, the obfuscation service provider node device can use the supervisable and provable obfuscation algorithm described in Embodiment 1 above to perform confidential transactions on the target according to the first challenge parameter after the signature and the random mapping parameter. Make a supervisable proof of confusion. Among them, the target confidential transaction is a confidential transaction that needs to be obfuscated and encrypted.

Optionally, the method further includes:

Saving the signed first challenge parameter and the random mapping parameter;

Obtain the target confidential transaction sent by the supplier node device, and use the signed first challenge parameter and the random mapping parameter to supervise the target confidential transaction.

In this embodiment, the regulatory agency node device can save the signed first challenge parameter and the random mapping parameter, and when the target confidential transaction sent by the supplier node device is obtained on the blockchain, it can use all The signed first challenge parameter and the random mapping parameter decrypt, supervise and track the confusion of the target confidential transaction.

In the method flow described in Figure 2, since the random mapping parameter and the first challenge parameter for the obfuscation proof of the obfuscated service provider node equipment are obtained from the supervisory authority node equipment, the supervisory authority node equipment can generate by itself The stored random mapping parameters and the first challenge parameter after signing supervise transactions on the blockchain, and at the same time, track the confusion of transactions.

The above are only specific embodiments of the present invention, but the scope of protection of the present invention is not limited to this. For those of ordinary skill in the art, without departing from the inventive concept of the present invention, they can also make Improvements, but these all belong to the protection scope of the present invention.

Please refer to Fig. 3, which is a functional block diagram of a preferred embodiment of a transaction data obfuscation device disclosed in the present invention.

In some embodiments, the transaction data obfuscation device runs in obfuscated service provider node equipment. The transaction data obfuscation device may include multiple functional modules composed of program code segments. The program code of each program segment in the transaction data obfuscation device can be stored in a memory and executed by at least one processor to execute part or all of the block chain-based transaction data obfuscation method described in FIG. 1 step.

In this embodiment, the transaction data obfuscation device can be divided into multiple functional modules according to the functions it performs. The functional modules may include: a receiving module 301, a confusion module 302, an acquisition module 303, a calculation module 304, a certification module 305, and an output module 306. The module referred to in the present invention refers to a series of computer program segments that can be executed by at least one processor and can complete fixed functions, and are stored in a memory.

The receiving module 301 is configured to receive an obfuscation request sent by the supplier node device for the target confidential transaction, where the obfuscation request carries the target random number.

Wherein, the obfuscation request carries a target random number, and the target random number is used to obfuscate the original transaction on the blockchain. Wherein, the target confidential transaction may be one or multiple.

The supplier node device needs to perform a series of operations in advance before sending the obfuscation request.

For example, suppose the target confidential transaction

The supplier node device sends a transaction

On the chain, with Gas, where g and h are system parameters, x ₁ is the transaction amount, r ₁ is a random number, and Gas represents the number of times the transaction can be confused.

First, the supplier node device selects the target random number r ₂ and calculates the result after confusion

And after the confusion, the specific value of Gas' and Gas' depends on the setting of the specific parameters of the system. Assuming that the initial value of Gas is 3, it will be reduced by 1 each time it is confused. The supplier node device calculates hash ₁ = Hash(C′ ₁ ||Gas′), and maps _{hash 1 to}

for

among them,

Is the value range of the transaction amount,

Is the transaction amount, and calculate

And provide proof: Chaum-Pedersen(C′ ₁ ,C _Hash ),

Among them, C _Hash is an intermediate variable, and Chaum-Pedersen (C′ ₁ , C _Hash ) proves that the supplier node device can expose C′ ₁ , which means that the supplier node device is the owner of the target confidential transaction By;

It is proved that the Gas after this round of confusion is the correct Gas value that can be accepted by the supplier's node equipment.

After that, the supplier node device can carry

The obfuscation request of is sent to the obfuscated service provider node device to trigger the obfuscated service provider node device to obfuscate the target confidential transaction.

Among them, Chaum-Pedersen proves to belong to the prior art, so I won't repeat it here.

The obfuscation module 302 is configured to obfuscate the target confidential transaction by using the target random number to obtain an obfuscated transaction.

Specifically, the obfuscation module 302 uses the target random number to obfuscate the target confidential transaction, and obtaining the obfuscated transaction includes:

Use the following formula to obfuscate the target confidential transaction using the target random number to obtain a confused transaction. The formula is:

C′ _i = h ^r C _π(i)

Wherein, the C′ _i is the obfuscated transaction, C _π(i) is the target confidential transaction, h is a system parameter, and r is the target random number.

Wherein, the target confidential transaction is equivalent to the obfuscated transaction.

The obtaining module 303 is configured to obtain the random mapping parameter and the signed first challenge parameter from the regulatory agency node device.

Among them, after the obfuscated service provider node device calculates the obfuscated transaction, it also needs to perform obfuscation proof.

In order to facilitate the supervision of the transaction by the supervisor, the random mapping parameter and the signed first challenge parameter can be obtained in advance from the node device of the supervisory authority, where the random mapping parameter π(i) falls within the range of [1, k] , {Π(1),π(2),...,π(k)} is a rearrangement of {1,2,...,k}.

Wherein, the first challenge parameter x=Hash(C _A1 ||...||C _Au ),

g ₁ , g ₂ ,..., g _v , h are all system parameters, and {r _A1 ,..., r _Au } are u random variables.

After the regulatory agency node device generates the first challenge parameter x, it can use the private key to sign the first challenge parameter x and send it to the obfuscated service provider node device.

The calculation module 304 is configured to generate a plurality of first random numbers, calculate a second challenge parameter according to the plurality of first random numbers and the first challenge parameter, and calculate a third challenge according to the second challenge parameter parameter.

The second challenge parameter y=Hash(C _B1 ||...||C _Bu ), where,

g ₁ , g ₂ ,..., g _v , h are all system parameters, {s ₁ ,..., s _u } are the u first random numbers, x is the first challenge parameter, and π(i) is For the random mapping parameter, the range of π(i) is [1, k], and C _Bi is the third intermediate variable.

The third challenge parameter z=Hash(C _B1 ||...||C _Bu ||y), the first intermediate variable

among them,

The second intermediate variable

Among them, ρ _i is the second random number.

The calculation module 304 is also used to calculate the first intermediate variable and the second intermediate variable.

Wherein, the first intermediate variable is

The second intermediate variable is

Wherein, ρ _i is a random number generated by the obfuscated service provider node device itself.

The proof module 305 is configured to perform product proof according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable.

Specifically, the certification module 305 performs product certification according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable, including:

The product proof formula is used to perform product proof according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable, and the product proof formula is as follows:

Among them, other intermediate variables can also be used in the specific proof method of the product proof, and the specific method of the product proof belongs to the existing technology, and will not be repeated here. The above product proof can be used to prove that the obfuscated service provider node device has found a random obfuscation π(i), and prove that the order before and after the obfuscation is disturbed.

The proof module 305 is further configured to perform exponentiation proof according to the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable.

Specifically, the proof module 305 performs the exponentiation proof according to the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable, including:

Using the power proof formula, the power proof is performed according to the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable, wherein the power proof formula is as follows:

Among them, the

Is the target confidential transaction,

For the said obfuscated transaction.

Among them, other intermediate variables can also be used in the specific proof method of the power proof, and the specific method of the power proof belongs to the existing technology, and will not be repeated here. The above proof of power can be used to prove that the π(i) in the power proof and the π(i) used in the product proof are the same π(i), which proves that the method of confusion is the same.

Among them, since the random mapping parameters and the signed first challenge parameter are obtained from the regulatory agency node device, the random mapping parameter obtained from the regulatory agency node device and the signed first challenge parameter are used to perform a provable confusion algorithm It can be called a verifiable shuffle with multi-regulators. Subsequent regulatory agency node devices can use their own saved random mapping parameters and signed first challenge parameters to track and supervise the transactions that need to be confused.

The output module 306 is configured to output the confusion transaction, the result of the product proof, and the result of the power proof.

Optionally, it can also output the relevant parameters and certifications provided by the above-mentioned supplier node equipment, such as output

In the device described in Figure 3, the target confidential transaction is an encrypted transaction. Only both parties to the transaction can decrypt the amount in the target confidential transaction, which protects the transaction privacy from being leaked. At the same time, by obfuscating the target confidential transaction, The obfuscated transaction equivalent to the target confidential transaction realizes the anonymity of the transaction. At the same time, the required parameters are obtained from the node device of the supervisory authority, which is convenient for the supervisor to supervise the transaction data on the chain.

Please refer to FIG. 4, which is a functional module diagram of a preferred embodiment of a transaction data obfuscation device disclosed in the present invention.

In some embodiments, the transaction data obfuscation device runs in obfuscated service provider node equipment. The transaction data obfuscation device may include multiple functional modules composed of program code segments. The program code of each program segment in the transaction data obfuscation device may be stored in a memory and executed by at least one processor to execute part or all of the block chain-based transaction data obfuscation method described in FIG. 2 step.

In this embodiment, the transaction data obfuscation device can be divided into multiple functional modules according to the functions it performs. The functional modules may include: a generation module 401, a calculation module 402, a signature module 403, and a sending module 404. The module referred to in the present invention refers to a series of computer program segments that can be executed by at least one processor and can complete fixed functions, and are stored in a memory.

The generating module 401 is used to generate random mapping parameters.

Among them, the regulatory agency node device can randomly select a random mapping parameter π(i), where the random mapping parameter π(i) belongs to the range of [1, k], {π(1), π(2),... ,π(k)} is the rearrangement of {1,2,...,k}.

The calculation module 402 is configured to calculate the first challenge parameter according to the random mapping parameter.

The regulatory agency node device may calculate the first challenge parameter according to the random mapping parameter.

Specifically, it can be calculated

x=Hash(C _A1 ||...||C _Au ),

Among them, g ₁ , g ₂ ,..., g _v , h are all system parameters, {r _A1 ,..., r _Au } are u random variables, and x is the first challenge parameter.

The signature module 403 is configured to use a private key to sign the first challenge parameter.

The supervisory authority node device may use the private key to sign the first challenge parameter, and save the signature locally.

The sending module 404 is configured to send the signed first challenge parameter and the random mapping parameter to the obfuscated service provider node device, so that the obfuscated service provider node device can according to the signed first challenge parameter and The random mapping parameter performs supervisable confusion proof for the target confidential transaction.

Wherein, the regulatory agency node device may send the signed first challenge parameter and the random mapping parameter to the obfuscated service provider node device after generating the random mapping parameter and the signed first challenge parameter. In this way, the obfuscation service provider node device can use the supervisable and provable obfuscation algorithm described in Embodiment 1 above to perform confidential transactions on the target according to the first challenge parameter after the signature and the random mapping parameter. Make a supervisable proof of confusion. Among them, the target confidential transaction is a confidential transaction that needs to be obfuscated and encrypted.

Optionally, the transaction data obfuscation device further includes:

A saving module, configured to save the signed first challenge parameter and the random mapping parameter;

The obtaining module is used to obtain the target confidential transaction sent by the supplier node device;

The supervision module is configured to use the signed first challenge parameter and the random mapping parameter to supervise the target confidential transaction.

In this embodiment, the regulatory agency node device can save the signed first challenge parameter and the random mapping parameter, and when the target confidential transaction sent by the supplier node device is obtained on the blockchain, it can use all The signed first challenge parameter and the random mapping parameter decrypt, supervise and track the confusion of the target confidential transaction.

In the device described in Figure 4, since the random mapping parameter and the first challenge parameter for the obfuscated service provider node device to perform the obfuscation proof are obtained from the regulatory agency node device, the regulatory agency node device can use its own generation and The saved random mapping parameters and the first challenge parameter after signing supervise transactions on the blockchain, and at the same time, track the confusion of transactions.

Please refer to FIG. 5, which is a schematic structural diagram of a blockchain node device according to a preferred embodiment of the method for obfuscation of transaction data based on blockchain according to the present invention. In this embodiment, the blockchain node device 5 may include a memory 51, a processor 52, a bus 53 and a transceiver 54.

FIG. 5 only shows the blockchain node device 5 with components 51-54. Those skilled in the art can understand that the structure shown in FIG. 5 does not constitute a limitation on the blockchain node device 5. It may be a bus-type structure or a star-shaped structure. The blockchain node device 5 may also include fewer or more components than shown in the figure, or a combination of certain components, or a different component arrangement. Other existing or future electronic products that can be adapted to the present invention should also be included in the protection scope of the present invention, and are included here by reference.

The memory 51 includes at least one type of readable storage medium, and the readable storage medium includes flash memory, hard disk, multimedia card, card-type memory (for example, SD or DX memory, etc.), magnetic memory, magnetic disk, optical disk, and the like. The memory 51 may be an internal storage unit of the blockchain node device 5 in some embodiments, such as a hard disk of the blockchain node device 5. In other embodiments, the memory 51 may also be an external storage device of the blockchain node device 5, such as a plug-in hard disk equipped on the blockchain node device 5, a smart memory card (Smart Media Card, SMC). ), Secure Digital (SD) card, Flash Card, etc. Further, the memory 51 may also include not only the internal storage unit of the blockchain node device 5, but also an external storage device. The memory 51 can not only be used to store application programs and various data installed in the blockchain node device 5, for example, a transaction data obfuscation device and its various functional modules, but also can be used to temporarily store what has been output or will be output. data.

The processor 52 may be a central processing unit (CPU), controller, microcontroller, or microprocessor in some embodiments, and is used to run program codes or process data stored in the memory 51.

The bus 53 may be a peripheral component interconnect standard (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus can be divided into address bus, data bus, control bus and so on. For ease of presentation, only one thick line is used to represent in FIG. 5, but it does not mean that there is only one bus or one type of bus.

Further, the blockchain node device 5 may also include a network interface, and the network interface may optionally include a wired interface and/or a wireless interface (such as a WI-FI interface, a Bluetooth interface, etc.), which is usually used in the block The link node device 5 establishes a communication connection with other dispatch servers.

Optionally, the blockchain node device 5 may also include a user interface, the user interface may include a display (Display), an input unit, such as a keyboard (Keyboard), optionally, the user interface may also include a standard wired interface, wireless interface. Optionally, in some embodiments, the display may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, an organic light-emitting diode (OLED) touch device, and the like. The display may also be called a display screen or a display unit, which is used to display the messages processed in the dispatch server and to display a visualized user interface.

With reference to FIG. 1, when the blockchain node device 5 is a confusing service provider node device, a plurality of instructions are stored in the memory 51, and the processor 52 can execute the plurality of instructions to achieve:

Receiving an obfuscation request sent by a supplier node device for a target confidential transaction, where the obfuscation request carries the target random number;

Use the target random number to confuse the target confidential transaction to obtain a confused transaction;

Obtain random mapping parameters and signed first challenge parameters from the regulatory agency node equipment;

Generating a plurality of first random numbers, calculating a second challenge parameter according to the plurality of first random numbers and the first challenge parameter, and calculating a third challenge parameter according to the second challenge parameter;

Calculate the first intermediate variable and the second intermediate variable;

Perform product proof according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable;

Performing a power proof according to the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable;

Output the result of the confusing transaction, the result of the product proof, and the result of the power proof.

In an optional implementation manner, the processor 52 uses the target random number to obfuscate the target confidential transaction, and obtaining the obfuscated transaction includes:

Use the following formula to obfuscate the target confidential transaction using the target random number to obtain a confused transaction. The formula is:

C′ _i = h ^r C _π(i)

Wherein, the C′ _i is the obfuscated transaction, C _π(i) is the target confidential transaction, h is a system parameter, and r is the target random number.

In an optional implementation manner, the second challenge parameter y=Hash(C _B1 ||...||C _Bu ), where,

g ₁ , g ₂ ,..., g _v , h are all system parameters, {s ₁ ,..., s _u } are the u first random numbers, x is the first challenge parameter, and π(i) is For the random mapping parameter, the range of π(i) is [1, k], and C _Bi is the third intermediate variable.

In an optional implementation manner, the third challenge parameter z=Hash(C _B1 ||...||C _Bu ||y), the first intermediate variable

among them,

The second intermediate variable

Among them, ρ _i is the second random number.

In an optional implementation manner, the processor 52 performing product certification according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable includes:

The product proof formula is used to perform product proof according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable, and the product proof formula is as follows:

In an optional implementation manner, the processor 52 performing the exponentiation proof according to the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable includes:

Use the power proof formula to perform the power proof based on the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable, where the power proof formula is as follows:

Among them, the

Is the target confidential transaction,

For the said obfuscated transaction.

Specifically, for the specific implementation method of the above-mentioned instructions by the processor 52, reference may be made to the description of the relevant steps in the embodiment corresponding to FIG. 1, which will not be repeated here.

With reference to Fig. 2, when the blockchain node device 5 is a regulatory agency node device, multiple instructions are stored in the memory 51, and the processor 52 can execute the multiple instructions to achieve:

Generate random mapping parameters;

Calculating the first challenge parameter according to the random mapping parameter;

Use the private key to sign the first challenge parameter;

The signed first challenge parameter and the random mapping parameter are sent to the obfuscated service provider node device, so that the obfuscated service provider node device can use the signed first challenge parameter and the random mapping parameter pair The target confidential transaction performs a supervisable proof of confusion.

In an optional implementation manner, the processor 52 may also execute the multiple instructions to achieve:

Saving the signed first challenge parameter and the random mapping parameter;

Obtain the target confidential transaction sent by the supplier node device, and use the signed first challenge parameter and the random mapping parameter to supervise the target confidential transaction.

Specifically, for the specific implementation method of the above-mentioned instructions by the processor 52, reference may be made to the description of the relevant steps in the embodiment corresponding to FIG. 2, which will not be repeated here.

In the above-mentioned embodiments, it may be implemented in whole or in part by application programs, hardware, firmware, or any combination thereof. When implemented using an application program, it can be implemented in the form of a computer program product in whole or in part.

The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on the computer, the processes or functions described in the embodiments of the present invention are generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website, computer, server, or data center. Transmission to another website site, computer, server or data center via wired (for example, coaxial cable, optical fiber, digital subscriber line) or wireless (for example, infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be stored by a computer or a data storage device such as a server or a data center integrated with one or more available media. The usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, and a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk (SSD)).

In the several embodiments provided by the present invention, it should be understood that the disclosed system, device, and method may be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the modules is only a logical function division, and there may be other division methods in actual implementation.

The modules described as separate components may or may not be physically separated, and the components displayed as modules may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the objectives of the solutions of the embodiments.

In addition, the functional modules in the various embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware, or may be implemented in the form of hardware plus software functional modules.

For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description, and therefore it is intended to fall within the claims. All changes within the meaning and scope of the equivalent elements of are included in the present invention. Any associated diagram marks in the claims should not be regarded as limiting the claims involved. Multiple units or devices stated in the system claims can also be implemented by software or hardware.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be Modifications or equivalent replacements are made without departing from the spirit and scope of the technical solution of the present invention.

Claims (10)

1. A block chain-based transaction data obfuscation method, which is applied to obfuscate service provider node equipment, and is characterized in that the method includes:

   Receiving an obfuscation request sent by a supplier node device for a target confidential transaction, where the obfuscation request carries the target random number;

   Use the target random number to confuse the target confidential transaction to obtain a confused transaction;

   Obtain random mapping parameters and signed first challenge parameters from the node device of the regulatory agency;

   Generating a plurality of first random numbers, calculating a second challenge parameter according to the plurality of first random numbers and the first challenge parameter, and calculating a third challenge parameter according to the second challenge parameter;

   Calculate the first intermediate variable and the second intermediate variable;

   Perform product proof according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable;

   Performing a power proof according to the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable;

   Output the result of the confusing transaction, the result of the product proof, and the result of the power proof.
2. The method according to claim 1, wherein the using the target random number to obfuscate the target confidential transaction, and obtaining the obfuscated transaction comprises:

   Use the following formula to obfuscate the target confidential transaction using the target random number to obtain a confused transaction. The formula is:

   C′ _i = h ^r C _π(i)

   Wherein, the C′ _i is the obfuscated transaction, C _π(i) is the target confidential transaction, h is a system parameter, and r is the target random number.
3. The method according to claim 2, wherein the second challenge parameter y=Hash(C _B1 ||...||C _Bu ), wherein,

   

   h are all system parameters, {s ₁ ,..., s _u } are the u first random numbers, x is the first challenge parameter, π(i) is the random mapping parameter, and π(i) is The range is [1, k], and C _Bi is the third intermediate variable.
4. The method according to claim 3, wherein the third challenge parameter z=Hash(C _B1 ||...||C _Bu ||y), the first intermediate variable

   

   among them,

   

   The second intermediate variable

   

   Among them, ρ _i is the second random number.
5. The method according to claim 4, wherein the performing product proof according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable comprises:

   The product proof formula is used to perform product proof according to the first challenge parameter, the second challenge parameter, the third challenge parameter, and the first intermediate variable, and the product proof formula is as follows:

   
6. The method according to claim 5, wherein said performing a power proof based on said target confidential transaction, said obfuscated transaction, said random mapping parameter and said second intermediate variable comprises:

   Using the power proof formula, the power proof is performed according to the target confidential transaction, the obfuscated transaction, the random mapping parameter, and the second intermediate variable, wherein the power proof formula is as follows:

   

   Among them, the

   

   Is the target confidential transaction,

   

   For the said obfuscated transaction.
7. A block chain-based transaction data obfuscation method applied to a node device of a regulatory agency, characterized in that the method includes:

   Generate random mapping parameters;

   Calculating the first challenge parameter according to the random mapping parameter;

   Use the private key to sign the first challenge parameter;

   The signed first challenge parameter and the random mapping parameter are sent to the obfuscated service provider node device, so that the obfuscated service provider node device can use the signed first challenge parameter and the random mapping parameter pair The target confidential transaction performs a supervisable proof of confusion.
8. The method according to claim 7, wherein the method further comprises:

   Saving the signed first challenge parameter and the random mapping parameter;

   Obtain the target confidential transaction sent by the supplier node device, and use the signed first challenge parameter and the random mapping parameter to supervise the target confidential transaction.
9. A block chain node device, characterized in that the block chain node device includes a memory and a processor, and the memory stores the download of a method for proof supervision of blockchain transaction data that can run on the processor A program, when the download program of the blockchain transaction data certification supervision method is executed by the processor, the blockchain-based transaction data obfuscation method according to any one of claims 1 to 8 is realized.
10. A computer-readable storage medium is characterized in that a download program of a blockchain transaction data certification supervision method is stored on the computer-readable storage medium, and the download program of the blockchain transaction data certification supervision method can be Or multiple processors are executed to implement the blockchain-based transaction data obfuscation method according to any one of claims 1 to 8.

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