WO2022120886A1

WO2022120886A1 - Commodity transaction method and apparatus, computer device, storage medium, and system

Info

Publication number: WO2022120886A1
Application number: PCT/CN2020/136244
Authority: WO
Inventors: 刘宏伟; 韦家全; 张鹏
Original assignee: 深圳技术大学
Priority date: 2020-12-10
Filing date: 2020-12-14
Publication date: 2022-06-16
Also published as: CN112581127A

Abstract

A commodity transaction method, an apparatus, a computer device, a storage medium and a system. Said method is applied to a blockchain platform, and comprises: receiving first ciphertext sent by a seller terminal and obtained after performing first encryption on commodity information of a digital commodity using a proxy re-encryption algorithm (S101); receiving a transaction request sent by the buyer terminal for requesting to transact the digital commodity (S102); determining whether the transaction request is present in a preset transaction list, when the transaction request is not in the transaction list, triggering a transaction instruction, so that the seller terminal monitors the transaction request and generates a re-encryption key according to the transaction request (S103); and receiving the re-encryption key sent by the seller terminal and performing verification, when the verification is passed, encrypting and converting the first ciphertext of the digital commodity and saving same into second ciphertext, adding the transaction request to the transaction list, and sending the pre-payment to the seller terminal, so that the buyer terminal decrypts the symmetric key, and decrypts the plaintext information of the digital commodity in the file management platform (S104).

Description

Commodity transaction method and device, computer equipment, storage medium and system

technical field

The embodiments of the present invention relate to the field of blockchain technology, and in particular, to a commodity transaction method and device, computer equipment, storage medium and system.

Background technique

With the development of information technology, books, software, music, movies and other products that used to be traded through material carriers such as paper, audio tapes, and CD-ROMs can now be delivered electronically through the Internet. Such intangible goods that are transmitted and delivered through the network and can be supplied directly through the network are called digital goods. In order to ensure the fairness of digital commodity transactions and avoid dishonest behavior by sellers or buyers, a common strategy is to introduce a third-party authority to participate in digital commodity transactions. After the digital commodity is traded, the payment is obtained, thereby ensuring the fairness of the digital commodity transaction.

Although the third party undertakes functions such as pre-guarantee and dispute resolution, the third-party-based digital commodity trading model still has the following problems: First, since the transaction is based on the complete trust of the buyer and the seller on the third-party platform and the fairness of the transaction depends on the third-party This behavior will over-rely on third-party platforms and increase the risk of transactions; secondly, third parties will charge transaction fees for transactions, resulting in high transaction costs for digital commodities; thirdly, the plaintext data of digital commodities is directly exposed to third-party platforms, lacking data privacy and copyright protection.

technical problem

Embodiments of the present invention provide a commodity transaction method, device, computer equipment, and storage medium.

technical solutions

In order to solve the above technical problems, a technical solution adopted by the embodiments of the present invention is to provide a commodity trading method, characterized in that, the method is applied to a blockchain platform and includes the following steps:

Receive the first ciphertext sent by the seller's terminal after performing the first encryption on the commodity information of the digital commodity by the proxy re-encryption algorithm;

Receive a transaction request sent by the buyer's terminal for requesting to trade the digital commodity, wherein the transaction request includes: a prepayment for purchasing the digital commodity;

Determine whether the transaction request exists in the preset transaction list, and when the transaction request is not in the transaction list, trigger a transaction instruction, so that the seller terminal monitors the transaction request and generates according to the transaction request re-encryption key;

Receive the re-encryption key sent by the seller terminal and verify it, when the verification is passed, encrypt and convert the first ciphertext of the digital commodity and save it as the second ciphertext, and add the transaction request to the transaction list and send the prepayment to the seller's terminal, so that the buyer's terminal can view the second ciphertext and decrypt to obtain the symmetric key of the digital commodity. Decrypt the symmetric encrypted ciphertext pre-uploaded by the seller terminal according to the symmetric key to obtain the plaintext information of the digital commodity.

Optionally, the method further includes:

When the re-encryption key sent by the seller terminal and the arbitration request sent by the buyer terminal are not received within a preset time period, the transaction is terminated, and the prepayment is returned to the buyer terminal .

Optionally, the method further includes:

receiving an arbitration request sent by the buyer's terminal;

Determine the attribution of the defaulting party, when the defaulting party is the buyer, terminate the transaction and return the advance payment to the buyer's terminal;

When the defaulting party is the seller, the transaction is terminated, the prepayment is returned to the buyer's terminal, and the security deposit pre-stored in the blockchain platform by the seller's terminal is deducted.

Optionally, the method further includes:

When the transaction request is in the transaction list or when the verification fails, the transaction is terminated and the prepayment is returned to the buyer's terminal.

In order to solve the above technical problems, an embodiment of the present invention also provides a commodity trading device, including:

an acquisition module, configured to receive the first ciphertext obtained by performing the first encryption on the commodity information of the digital commodity through the proxy re-encryption algorithm and sent by the seller's terminal;

The acquiring module is further configured to receive a transaction request sent by the buyer's terminal for requesting to trade the digital commodity, wherein the transaction request includes: prepayment for purchasing the digital commodity;

The processing module is used for judging whether the transaction request exists in the preset transaction list, and when the transaction request is not in the transaction list, triggering a transaction instruction, so that the seller terminal monitors the transaction request and follows the transaction request. the transaction request generates a re-encryption key;

an execution module, configured to receive the re-encryption key sent by the seller's terminal and verify it, and when the verification is passed, add the transaction request to the transaction list and send the prepayment to the seller terminal, and encrypting and converting the first ciphertext of the digital commodity and saving it as a second ciphertext, so that after the buyer terminal checks the second ciphertext and decrypts to obtain the symmetric key of the digital commodity, In the file management platform, the first ciphertext pre-uploaded by the seller terminal is decrypted according to the symmetric key to obtain the plaintext information of the digital commodity.

Optionally, also include:

The first processing submodule is further configured to terminate the transaction when the re-encryption key sent by the seller terminal and the arbitration request sent by the buyer terminal are not received within a preset time period, and the The advance payment is returned to the buyer's terminal.

Optionally, also include:

The first acquisition submodule is further configured to receive an arbitration request sent by the buyer terminal;

The second processing sub-module is to determine the attribution of the defaulting party, and when the defaulting party is the buyer, terminate the transaction and return the prepayment to the buyer's terminal;

The third processing sub-module, when the defaulting party is the seller, terminates the transaction, returns the prepayment to the buyer's terminal and deducts the deposit pre-stored in the blockchain platform by the seller's terminal.

Optionally, also include:

The fourth processing sub-module, when the transaction request is in the transaction list or when the verification fails, terminate the transaction and return the prepayment to the buyer's terminal.

In order to solve the above technical problems, an embodiment of the present invention further provides a commodity trading system, including: a blockchain platform, a buyer's terminal, a seller's terminal, and a file management platform; wherein,

The seller terminal is used for the first ciphertext obtained by symmetrically encrypting the commodity information of the digital commodity and sending the first ciphertext to the blockchain platform and the file management platform;

the buyer terminal, configured to send a transaction request for requesting to trade the digital commodity to the blockchain platform, wherein the transaction request includes: prepayment for purchasing the digital commodity;

The blockchain platform is used to determine whether the transaction request exists in a preset transaction list, and when the transaction request is not in the transaction list, trigger a transaction instruction;

the seller terminal, configured to monitor the transaction request and generate a re-encryption key according to the transaction request, and send the re-encryption key to the blockchain platform;

the blockchain platform is configured to receive the re-encryption key and perform verification, and when the verification is passed, add the transaction request to the transaction list and send the prepayment to the seller terminal, and encrypting and converting the first ciphertext of the digital commodity and saving it as the second ciphertext;

the buyer's terminal, configured to obtain the second ciphertext and decrypt it to obtain the symmetric key of the digital commodity and send it to the file management platform;

The file management platform is configured to decrypt the first ciphertext according to the symmetric key to obtain plaintext information of the digital commodity.

To solve the above technical problem, an embodiment of the present invention further provides a computer device, including a memory and a processor, the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, all The processor executes the steps of the commodity transaction method described above.

In order to solve the above technical problem, an embodiment of the present invention further provides a storage medium storing computer-readable instructions. When the computer-readable instructions are executed by one or more processors, the one or more processors execute the above-mentioned Describe the steps of the commodity trading method.

beneficial effect

Since the blockchain has the characteristics of decentralization, openness, and non-tampering, the commodity transaction method is applied to the blockchain, and the fair transaction of digital commodities can be realized with the help of blockchain, and the issuance of digital commodities and the collection of payments can be realized. At the same time, due to the openness of the blockchain, it can avoid excessive dependence on third-party trust, reduce transaction risks, and use the blockchain platform to reduce costs. In addition, in terms of privacy protection of digital commodities, by re-encrypting commodity information, the delegation of decryption authority can be implemented on the premise that the digital commodity is encrypted, and the entrusted decryption authority of the digital commodity can be obtained if and only after the buyer pays, which enhances the privacy.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained from these drawings without creative effort.

FIG. 1 is a schematic diagram of a basic flow of a commodity trading method provided by an embodiment of the present invention;

FIG. 2 is a basic structural block diagram of a commodity trading device provided by an embodiment of the present invention;

FIG. 3 is a basic structural block diagram of a commodity trading system provided by an embodiment of the present invention;

FIG. 4 is a basic structural block diagram of a computer device provided by an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

In order for those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

In some of the processes described in the description and claims of the present invention and the above-mentioned drawings, various operations are included in a specific order, but it should be clearly understood that these operations may not be in accordance with the order in which they appear herein. For execution or parallel execution, the sequence numbers of the operations, such as 101, 102, etc., are only used to distinguish different operations, and the sequence numbers themselves do not represent any execution order. Additionally, these flows may include more or fewer operations, and these operations may be performed sequentially or in parallel. It should be noted that the descriptions such as "first" and "second" in this document are used to distinguish different messages, devices, modules, etc., and do not represent a sequence, nor do they limit "first" and "second" are different types.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present invention.

Example

Those skilled in the art can understand that the "terminal" and "terminal device" used here include both a wireless signal receiver device that only has a wireless signal receiver without transmission capability, and a device that includes receiving and transmitting hardware. A device having receive and transmit hardware capable of performing two-way communications over a two-way communication link. Such equipment may include: cellular or other communication equipment, which has a single-line display or a multi-line display or a cellular or other communication device without a multi-line display; PCS (Personal Communications Service, personal communication system), which can combine voice, data Processing, fax and/or data communication capabilities; PDA (Personal Digital Assistant), which may include a radio frequency receiver, pager, Internet/Intranet access, web browser, notepad, calendar and/or GPS (Global Positioning System (Global Positioning System) receiver; conventional laptop and/or palmtop computer or other device having and/or including a conventional laptop and/or palmtop computer or other device with a radio frequency receiver. As used herein, "terminal", "terminal equipment" may be portable, transportable, mounted in a vehicle (air, marine and/or land), or adapted and/or configured to operate locally, and/or In distributed form, run at any other location on Earth and/or in space. The "terminal" and "terminal device" used here can also be a communication terminal, an Internet terminal, and a music/video playback terminal, such as a PDA, a MID (Mobile Internet Device) and/or a music/video playback terminal. It can also be a smart TV, a set-top box and other devices.

As shown in FIG. 1, FIG. 1 is a schematic diagram of a basic flow of a commodity trading method provided by an embodiment of the present invention, wherein the commodity trading method is applied to a blockchain, and the method includes the following steps:

S101. Receive a first ciphertext obtained by performing the first encryption of the commodity information of the digital commodity through the proxy re-encryption algorithm and sent by the seller's terminal;

In this embodiment, the seller is the party that has the right to sell digital commodities, which may be the producer of the digital commodity, or the party that only has the right to sell, wherein the seller has an Ethereum account in the Ethereum smart contract, which is used for The prepayment paid by the buyer is withdrawn after the transaction is successful.

In this embodiment, in order to facilitate transactions, the blockchain platform receives the first ciphertext sent by the seller's terminal and stores it in the blockchain platform. It should be noted that the blockchain has the characteristics of decentralization, openness, and non-tampering. In this embodiment, using the blockchain platform to realize commodity transactions can ensure the fairness and justice of transactions to the greatest extent, and reduce transaction risks. Reduce transaction costs. The blockchain platform used in this embodiment is the Ethereum smart contract, in which the smart contract is deployed by the seller, and the buyer and seller complete the digital commodity transaction by interacting with the smart contract. Arbitration in the event of a dispute. The funds involved in the digital commodities in this embodiment are ether. In this embodiment, the commodity information represents information such as the name, attribute, and purpose of the digital commodity, which is used to display the sold digital commodity to the buyer. In order to ensure the privacy of the commodity information, when the seller terminal sends the commodity information, the commodity information can be symmetrically encrypted, and the encryption algorithm used can be DES, AES, etc. The symmetric encryption algorithm defined in this embodiment is: SE={Enc, Dec}. The first ciphertext is the ciphertext obtained by symmetrically encrypting the commodity information.

In an embodiment of the present invention, the seller terminal performs symmetric encryption on the digital commodity M to obtain the ciphertext M': M'←SE.Enc(M,K). The symmetric key K is randomly selected. The seller terminal uploads M' to the file management platform, that is, a distributed file system (IPFS, Inter Planetary File System) for storing commodity information of digital commodities. At the same time, IPFS returns the hash value IPFShash. The seller terminal runs the UPPRE.Enc algorithm to encrypt the symmetric key K, obtains the first ciphertext CT _i of K, and uses the private key to sign CT _i ||IPFShash, and the signature result is recorded as Sig. In other embodiments, when When the seller is not the producer of digital goods, it should obtain this signature from the producer of digital goods. Encode param, CT _i , IPFShash, p _i and Sig into the Ethereum smart contract, then the seller deploys the Ethereum smart contract into Ethereum and deposits the security deposit into the Ethereum smart contract.

In an embodiment of the present invention, before step S101, the blockchain platform is initialized, and at the same time, the seller runs the UPPRE.Setup algorithm to generate public parameters param, including the generator g; runs the UPPRE.KeyGen algorithm to generate the seller's public and private parameters key, denote the public key pk _i =(pk _i1 , pk _i2 ), and the private key sk _i =(sk _i1 ,sk _i2 )=(x _i1 ,x _i2 ). Among them, x _i1 and x _i2 are random numbers.

S102. Receive a transaction request sent by the buyer's terminal for requesting to trade the digital commodity, wherein the transaction request includes: a prepayment for purchasing the digital commodity;

In the embodiment of the present invention, the buyer also has an Ethereum account in the Ethereum smart contract, which is mainly used for interacting with the smart contract, depositing the prepayment into the smart contract, and obtaining the plaintext of the digital commodity.

In an embodiment of the present invention, the buyer terminal uses the algorithm UPPRE.keyGen to generate the public key pk _j =(pk _j1 ,pk _j2 ), and the private key sk _j =(sk _j1 ,sk _j2 )=(x _j1 ,x _j2 ). Among them, x _j1 and x _j2 are random numbers. In addition, the buyer terminal uses the algorithm UPPRE.RequestGen to generate request information R, which includes the intermediate value δ, g ₂ , and the public key pk _j1 . And send the prepayment and request information R to the smart contract to apply for the purchase of digital goods.

S103. Determine whether the transaction request exists in a preset transaction list, and when the transaction request is not in the transaction list, trigger a transaction instruction, so that the seller terminal monitors the transaction request and executes the transaction according to the transaction request. request to generate a re-encryption key;

In an embodiment of the present invention, the preset transaction list is used to store the accepted transaction request information R. When the Ethereum smart contract receives the transaction request (R) sent by the buyer's terminal, it will first check whether the pk _j1 in R is It exists in the preset transaction list. If it already exists, the request information R will be rejected and the advance payment will be returned. Otherwise, the request message R is received. When the transaction request R is received, R is added to the list pk _j1 , and at the same time, the Ethereum smart contract triggers the transaction instruction, so that the event is monitored by the seller's terminal, which is used to inform the seller's terminal that the smart contract is waiting for the seller to submit the re-encryption key.

S104. Receive the re-encryption key sent by the seller's terminal and verify it, and when the verification is passed, encrypt and convert the first ciphertext of the digital commodity and save it as a second ciphertext, and store the transaction After requesting to be added to the transaction list and sending the prepayment to the seller terminal, so that the buyer terminal can view the second ciphertext and decrypt to obtain the symmetric key of the digital commodity, and then file management The platform decrypts the symmetric encrypted ciphertext pre-uploaded by the seller terminal according to the symmetric key to obtain the plaintext information of the digital commodity.

In an embodiment of the present invention, after the seller terminal monitors the transaction request R sent by the buyer terminal, it uses the algorithm UPPRE.RekeyGen to generate a re-encryption key

And submit it to the blockchain platform, namely the Ethereum smart contract, the Ethereum smart contract receives the submitted

Then execute the algorithm UPPRE.VerifyRekey to verify

correctness when re-encrypting the key

If it is correct, the verification is passed, the transaction request R is added to the transaction list pk _j1 and the prepayment is sent to the seller terminal, and the first ciphertext of the digital commodity is encrypted and converted and saved as the second ciphertext.

It should be noted that when verifying the re-encryption key

, verify the equation

with the equation

Whether it is established at the same time, when it is established at the same time, the re-encryption key

Correct, verified. And the Ethereum smart contract can output the second ciphertext CT _j by executing the algorithm UPPRE.ReEnc.

It should be noted that the buyer's terminal can view the second ciphertext CT _j in the account in the Ethereum smart contract and use sk _j to decrypt CT _j by executing the decryption algorithm UPPRE.Dec to obtain the symmetric key K: K←UPPRE.Dec At the same time, the buyer's terminal downloads M' in the file management platform (IPFS) according to IPFShash and decrypts to obtain the digital commodity plaintext M: M←SE.Dec(M', K).

In the embodiment of the present invention, since the blockchain has the characteristics of decentralization, openness and inspection, and non-tampering, the commodity transaction method is applied to the blockchain, and the fair transaction of digital commodities is realized by means of the blockchain. At the same time, due to the openness of the blockchain, it can avoid excessive dependence on third-party trust and reduce transaction risks. At the same time, using the blockchain platform can also reduce costs. In addition, in terms of privacy protection of digital commodities, by re-encrypting commodity information, the delegation of decryption authority can be implemented on the premise that the digital commodity is encrypted, and the entrusted decryption authority of the digital commodity can be obtained if and only after the buyer pays, which enhances the privacy.

Optionally, in some embodiments, in order to ensure the smooth progress of the commodity transaction and improve the transaction efficiency, the transaction can be terminated in time when the transaction is not completed within the preset time period, that is, the transaction is not received within the preset time period. When the re-encryption key is sent by the seller's terminal and the arbitration request sent by the buyer's terminal is not received, the transaction is terminated, and the prepayment is returned to the buyer's terminal.

Optionally, in some embodiments, in order to conduct fair transactions and protect the legitimate rights and interests of buyers or sellers, when transactions cannot be performed normally, the blockchain platform needs to conduct fair arbitration for transactions that cannot be performed normally. An arbitration method comprising the following steps:

Step 1, receiving the arbitration request sent by the buyer terminal;

It should be noted that when the content Ethereum smart contract does not receive the re-encryption key sent by the seller's terminal in the preset time period, it can submit an arbitration request.

Step 2: Judging the ownership of the defaulting party, when the defaulting party is the buyer, terminate the transaction and return the prepayment to the buyer's terminal;

Step 3: When the defaulting party is the seller, terminate the transaction, return the prepayment to the buyer's terminal and deduct the deposit pre-stored in the blockchain platform by the seller's terminal.

In the embodiment of the present invention, the blockchain platform, that is, the Ethereum smart contract, passes the verification equation

with the equation

established at the same time. If the above equations are not established at the same time, the smart contract determines that the buyer is in breach of contract, terminates the transaction, and refunds the advance payment. If the above equations are established at the same time, the smart contract determines that the seller is in breach of contract. The smart contract then deducts part of the seller's deposit as a penalty, returns the advance payment to the buyer, and terminates the transaction.

Optionally, in some embodiments, the method further includes:

Embodiments of the present invention also provide a commodity trading device. Please refer to FIG. 2 for details. FIG. 2 is a block diagram of the basic structure of the commodity trading apparatus according to this embodiment.

As shown in FIG. 2 , a commodity trading device includes: an acquisition module 2100 , a processing module 2200 and an execution module 2300 . Wherein, the obtaining module 2100 is used to receive the first ciphertext obtained by performing the first encryption of the proxy re-encryption algorithm on the commodity information of the digital commodity sent by the seller's terminal; the obtaining module 2100 is also used to receive the request sent by the buyer's terminal A transaction request for trading the digital commodity, wherein the transaction request includes: a prepayment for purchasing the digital commodity; the processing module 2200 is configured to determine whether the transaction request exists in the preset transaction list, when the When the transaction request is not in the transaction list, trigger a transaction instruction, so that the seller terminal monitors the transaction request and generates a re-encryption key according to the transaction request; the execution module 2300 is configured to receive the information sent by the seller terminal. The re-encryption key is verified, and when the verification is passed, the first ciphertext of the digital commodity is encrypted and converted and saved as the second ciphertext, and the transaction request is added to the transaction list and Send the prepayment to the seller terminal, so that the buyer terminal can view the second ciphertext and decrypt to obtain the symmetric key of the digital commodity, and then decrypt according to the symmetric key in the file management platform The symmetric encrypted ciphertext pre-uploaded by the seller terminal obtains the plaintext information of the digital commodity.

In the commodity trading device provided by the embodiments of the present invention, since the blockchain has the characteristics of decentralization, openness and inspection, and non-tampering, the commodity trading method is applied to the blockchain, and the transaction of digital commodities is realized by means of the blockchain. Fair trade, realize the issuance of digital goods and the collection of payments, and at the same time, due to the openness of the blockchain, it can avoid excessive reliance on third-party trust, reduce transaction risks, and use the blockchain platform to reduce costs. In addition, in terms of privacy protection of digital commodities, by re-encrypting commodity information, the delegation of decryption authority can be implemented on the premise that the digital commodity is encrypted, and the entrusted decryption authority of the digital commodity can be obtained if and only after the buyer pays, which enhances the privacy.

In some embodiments, it further includes: a first processing submodule, further configured to not receive the re-encryption key sent by the seller terminal and not receive the re-encryption key sent by the buyer terminal within a preset time period In the event of an arbitration request, the transaction is terminated and the advance payment is returned to the buyer's terminal.

In some embodiments, it further includes: a first acquiring sub-module, which is further configured to receive an arbitration request sent by the buyer terminal; a second processing sub-module, which determines the attribution of the defaulting party, and when the defaulting party is the buyer, terminates the transaction and sends The prepayment is returned to the buyer's terminal; the third processing sub-module, when the defaulting party is the seller, terminates the transaction, returns the prepayment to the buyer's terminal and deducts the seller's terminal to pre-store in the area Margin in a blockchain platform.

In some embodiments, it further includes: a fourth processing sub-module, which terminates the transaction and returns the prepayment to the buyer terminal when the transaction request is in the transaction list or when the verification fails.

In order to solve the above technical problems, the embodiment of the present invention also provides a commodity trading system. As shown in FIG. 3 , the commodity trading system includes: a blockchain platform 301, a buyer terminal 302, a seller terminal 303 and a file management platform 304; wherein,

The seller terminal 303 is used for the first ciphertext obtained by symmetrically encrypting the commodity information of the digital commodity and sending the first ciphertext to the blockchain platform 301 and the file management platform 304;

The buyer terminal 302 is configured to send a transaction request for requesting to trade the digital commodity to the blockchain platform 301, wherein the transaction request includes: prepayment for purchasing the digital commodity;

The blockchain platform 301 is configured to determine whether the transaction request exists in a preset transaction list, and trigger a transaction instruction when the transaction request is not in the transaction list;

the seller terminal 303, configured to monitor the transaction request and generate a re-encryption key according to the transaction request, and send the re-encryption key to the blockchain platform 301;

The blockchain platform 301 is configured to receive the re-encryption key and perform verification, and when the verification is passed, add the transaction request to the transaction list and send the prepayment to the seller terminal 303, and encrypting and converting the first ciphertext of the digital commodity and saving it as a second ciphertext;

The buyer terminal 302 is used to obtain the second ciphertext and decrypt it to obtain the symmetric key of the digital commodity and send it to the file management platform 304;

The file management platform 304 is configured to decrypt the first ciphertext according to the symmetric key to obtain plaintext information of the digital commodity.

In the commodity trading system provided by the embodiment of the present invention, since the blockchain has the characteristics of decentralization, openness, and non-tampering, the commodity trading method is applied to the blockchain, and the fair transaction of digital commodities is realized by means of the blockchain. , to realize the issuance of digital goods and the collection of payments. At the same time, due to the openness of the blockchain, it can avoid excessive dependence on third-party trust and reduce transaction risks. At the same time, the use of the blockchain platform can also reduce costs. In addition, in terms of privacy protection of digital commodities, by re-encrypting commodity information, the delegation of decryption authority can be implemented on the premise that the digital commodity is encrypted, and the entrusted decryption authority of the digital commodity can be obtained if and only after the buyer pays, which enhances the privacy.

To solve the above technical problems, the embodiments of the present invention further provide computer equipment. For details, please refer to FIG. 4 , which is a block diagram of a basic structure of a computer device according to this embodiment.

As shown in Figure 4, a schematic diagram of the internal structure of the computer equipment. As shown in FIG. 4, the computer device includes a processor, a non-volatile storage medium, a memory, and a network interface connected through a system bus. Wherein, the non-volatile storage medium of the computer device stores an operating system, a database and computer-readable instructions, and the database may store a sequence of control information. When the computer-readable instructions are executed by the processor, the processor can realize a A commodity trading method. The processor of the computer device is used to provide computing and control capabilities and support the operation of the entire computer device. Computer readable instructions may be stored in the memory of the computer device, and when executed by the processor, the computer readable instructions may cause the processor to perform a method of trading commodities. The network interface of the computer equipment is used for communication with the terminal connection. Those skilled in the art can understand that the structure shown in FIG. 4 is only a block diagram of a partial structure related to the solution of the present application, and does not constitute a limitation on the computer equipment to which the solution of the present application is applied. Include more or fewer components than shown in the figures, or combine certain components, or have a different arrangement of components.

In this embodiment, the processor is used to execute the specific content of the acquisition module 2100 , the processing module 2200 and the execution module 2300 in FIG. 2 , and the memory stores program codes and various types of data required to execute the above modules. The network interface is used for data transmission between user terminals or servers. The memory in this embodiment stores the program codes and data required to execute all the sub-modules in the commodity transaction method, and the server can call the server's program codes and data to execute the functions of all the sub-modules.

In the computer equipment provided by the embodiments of the present invention, since the blockchain has the characteristics of decentralization, openness, and non-tampering, the commodity transaction method is applied to the blockchain, and the fair transaction of digital commodities can be realized by means of the blockchain. Realize the issuance of digital goods and the collection of payments. At the same time, due to the openness of the blockchain, it can avoid excessive dependence on third-party trust and reduce transaction risks. At the same time, the use of the blockchain platform can also reduce costs. In addition, in terms of privacy protection of digital commodities, by re-encrypting commodity information, the delegation of decryption authority can be implemented on the premise that the digital commodity is encrypted, and the entrusted decryption authority of the digital commodity can be obtained if and only after the buyer pays, which enhances the privacy. The present invention also provides a storage medium storing computer-readable instructions, which, when executed by one or more processors, cause the one or more processors to execute the commodity trading method described in any of the foregoing embodiments A step of.

Those of ordinary skill in the art can understand that the realization of all or part of the processes in the methods of the above embodiments can be accomplished by instructing relevant hardware through a computer program, and the computer program can be stored in a computer-readable storage medium, and the program is During execution, it may include the processes of the embodiments of the above-mentioned methods. Wherein, the aforementioned storage medium may be a non-volatile storage medium such as a magnetic disk, an optical disk, a read-only memory (Read-Only Memory, ROM), or a random access memory (Random Access Memory, RAM) or the like.

It should be understood that although the various steps in the flowchart of the accompanying drawings are sequentially shown in the order indicated by the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless explicitly stated herein, the execution of these steps is not strictly limited to the order and may be performed in other orders. Moreover, at least a part of the steps in the flowchart of the accompanying drawings may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but may be executed at different times, and the execution sequence is also It does not have to be performed sequentially, but may be performed alternately or alternately with other steps or at least a portion of sub-steps or stages of other steps.

The above are only some embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made. It should be regarded as the protection scope of the present invention.

Claims

A commodity trading method, characterized in that the method is applied to a blockchain platform, comprising the following steps:

Receive the first ciphertext sent by the seller's terminal after performing the first encryption on the commodity information of the digital commodity by the proxy re-encryption algorithm;

Receive a transaction request sent by the buyer's terminal for requesting to trade the digital commodity, wherein the transaction request includes: a prepayment for purchasing the digital commodity;

Determine whether the transaction request exists in the preset transaction list, and when the transaction request is not in the transaction list, trigger a transaction instruction, so that the seller terminal monitors the transaction request and generates according to the transaction request re-encryption key;

Receive the re-encryption key sent by the seller's terminal and verify it, and when the verification is passed, encrypt and convert the first ciphertext of the digital commodity and save it as the second ciphertext, and add the transaction request to In the transaction list, the prepayment is sent to the seller terminal, so that the buyer terminal can view the second ciphertext and decrypt to obtain the symmetric key of the digital commodity. The symmetric key decrypts the symmetric encrypted ciphertext pre-uploaded by the seller terminal to obtain plaintext information of the digital commodity.
The commodity trading method according to claim 1, wherein the method further comprises:

When the re-encryption key sent by the seller terminal and the arbitration request sent by the buyer terminal are not received within a preset time period, the transaction is terminated, and the prepayment is returned to the buyer terminal .
The commodity trading method according to claim 1, wherein the method further comprises:

receiving an arbitration request sent by the buyer's terminal;

Determine the ownership of the defaulting party, and when the defaulting party is the buyer, terminate the transaction and return the advance payment to the buyer's terminal;

When the defaulting party is the seller, the transaction is terminated, the prepayment is returned to the buyer's terminal, and the security deposit pre-stored in the blockchain platform by the seller's terminal is deducted.
The commodity trading method according to claim 1, wherein the method further comprises:

When the transaction request is in the transaction list or when the verification fails, the transaction is terminated and the prepayment is returned to the buyer's terminal.
A commodity trading device, characterized in that it includes:

an acquisition module, configured to receive the first ciphertext obtained by performing the first encryption on the commodity information of the digital commodity through the proxy re-encryption algorithm and sent by the seller's terminal;

The acquiring module is further configured to receive a transaction request sent by the buyer's terminal for requesting to trade the digital commodity, wherein the transaction request includes: prepayment for purchasing the digital commodity;

The processing module is used for judging whether the transaction request exists in the preset transaction list, and when the transaction request is not in the transaction list, triggering a transaction instruction, so that the seller terminal monitors the transaction request and follows the transaction request. the transaction request generates a re-encryption key;

The execution module is configured to receive the re-encryption key sent by the seller terminal and verify it, and when the verification is passed, encrypt and convert the first ciphertext of the digital commodity and save it as the second ciphertext, and After adding the transaction request to the transaction list and sending the prepayment to the seller terminal, so that the buyer terminal can view the second ciphertext and decrypt to obtain the symmetric key of the digital commodity, In the file management platform, the symmetric encrypted ciphertext uploaded in advance by the seller terminal is decrypted according to the symmetric key to obtain the plaintext information of the digital commodity.
The commodity trading device according to claim 5, further comprising: a first processing submodule, further configured to not receive the re-encryption key sent by the seller terminal within a preset time period and When the arbitration request sent by the buyer terminal is not received, the transaction is terminated, and the prepayment is returned to the buyer terminal.
The commodity trading device according to claim 5, further comprising:

The first acquisition sub-module is further configured to receive an arbitration request sent by the buyer terminal;

The second processing sub-module is to determine the attribution of the defaulting party, and when the defaulting party is the buyer, terminate the transaction and return the prepayment to the buyer's terminal;

The third processing sub-module, when the defaulting party is the seller, terminates the transaction, returns the prepayment to the buyer's terminal and deducts the deposit pre-stored in the blockchain platform by the seller's terminal.
A computer device comprising a memory and a processor, wherein computer-readable instructions are stored in the memory, and when the computer-readable instructions are executed by the processor, the processor causes the processor to perform any one of claims 1 to 4. The steps of a method of trading commodities as claimed in one of the claims.
A storage medium storing computer-readable instructions that, when executed by one or more processors, cause the one or more processors to perform the execution of any one of claims 1 to 4 The steps of the commodity trading method.
A commodity trading system, comprising: a blockchain platform, a buyer's terminal, a seller's terminal and a file management platform; wherein,

The seller terminal is used for the first ciphertext obtained by symmetrically encrypting the commodity information of the digital commodity and sending the first ciphertext to the blockchain platform and the file management platform;

the buyer terminal, configured to send a transaction request for requesting to trade the digital commodity to the blockchain platform, wherein the transaction request includes: prepayment for purchasing the digital commodity;

The blockchain platform is used to determine whether the transaction request exists in a preset transaction list, and when the transaction request is not in the transaction list, trigger a transaction instruction;

the seller terminal, configured to monitor the transaction request and generate a re-encryption key according to the transaction request, and send the re-encryption key to the blockchain platform;

the blockchain platform is configured to receive the re-encryption key and perform verification, and when the verification is passed, add the transaction request to the transaction list and send the prepayment to the seller terminal, and encrypting and converting the first ciphertext of the digital commodity and saving it as the second ciphertext;

the buyer's terminal, configured to obtain the second ciphertext and decrypt it to obtain the symmetric key of the digital commodity and send it to the file management platform;

The file management platform is configured to decrypt the first ciphertext according to the symmetric key to obtain plaintext information of the digital commodity.