Privacy protection method for public opinion evidence information based on blockchain

Abstract

The present invention belongs to the field of information security technology, and specifically relates to a privacy protection method for public opinion evidence information based on blockchain. The present invention is that the notary department will store the information obtained from the information subject in a trusted data set that is not open to the public, extract the identity information about the information subject from this trusted data set, and use this identity information to generate a corresponding anonymous information subject. The notary department will use the identity of the anonymous information subject as an agent of the information subject to submit the commitment and proof of the public opinion evidence information that needs to be uploaded to the smart contract for verification. After the verification is legal, the public opinion evidence information will be added to the main chain of the public opinion evidence information for safekeeping. The present invention ensures that except for the core information related to the public opinion evidence information of the information subject, which is used to record on the chain, the rest of the information is safely stored, thereby technically ensuring the security and privacy of the subject information.

Description

Technical Field

[0001] The present invention belongs to the field of information security technology, and specifically relates to a privacy protection method for public opinion evidence information based on blockchain. Background Art

[0002] The electronic evidence storage of public opinion information has the potential to preserve a complete chain of evidence, making it easier to maintain and supervise in the future. This storage method in the era of information haul can not only improve the compliance of the evidence storage platform, but also constrain the evidence storage platform to a certain extent and protect the rights and interests of public opinion evidence holders.

[0003] However, the current electronic public opinion information storage method has the characteristics of easy modification and deletion of data, which makes it possible for the evidence data to be forged in the centralized storage server. Due to the single storage method of the centralized evidence storage platform, it is necessary to manually perform security authentication on the evidence data before uploading it to the platform's internal server. In this process, the credibility of the third-party evidence personnel cannot be ensured, which is prone to malicious tampering before data upload. In addition, more importantly, the data uploaded to the centralized server is also at risk of being stolen and attacked, and the privacy of public opinion evidence information cannot be effectively protected. Summary of the invention

[0004] In view of the deficiencies of the above-mentioned prior art, the present invention provides a privacy protection method for public opinion evidence information based on blockchain, with the aim of solving the technical problems that the prior art cannot ensure the credibility of third-party evidence custodians, is prone to malicious tampering before data upload, and data uploaded to a centralized server is also at risk of being stolen and attacked, and the privacy of public opinion evidence information cannot be effectively protected.

[0005] The privacy protection method of public opinion evidence information based on blockchain provided by the present invention has the following specific technical solutions:

[0006] The privacy protection method of public opinion evidence information based on blockchain includes the following steps:

[0007] S1, setting an information subject, wherein the information subject has an information set to be uploaded, and the information set includes core information and non-core information;

[0008] S2, the notary department receives the information set in step S1, and stores the information set in step S1 into a trusted data set kept by the government department through an internal signature;

[0009] S3, after the information is stored, the core information in the information set of one or more stored information subjects is extracted to construct an anonymous information subject, and the identity of the anonymous information subject is used to perform the on-chain operation of the public opinion evidence information;

[0010] S4, the anonymous information subject in step S3 has the encrypted public opinion evidence information, and performs privacy encapsulation on the encrypted public opinion evidence information, and constructs a commitment and proof of the encrypted public opinion evidence information;

[0011] S5, the smart contract on the blockchain takes the commitment, proof and related input parameters from the transmission channel for verification. After the verification is legal, the public opinion evidence information is added to the public opinion evidence information main chain for safekeeping.

[0012] In certain embodiments, in step S1, the personal information includes ID number and mobile phone number, and the non-core information includes gender and age.

[0013] In some implementations, in step S2, the internal signature is a department identification used by the notary department for signing, and is verified by the trusted data set. After the verification is passed, the internal signature is saved as information.

[0014] In certain embodiments, in step S4, the privacy encapsulation is to submit only the commitment, proof and related encrypted input information of the public opinion evidence when interacting with the smart contract on the chain.

[0015] In certain embodiments, in step S4, the commitment is used to announce to the outside that the anonymous information subject has uploaded a piece of public opinion information. The commitment is generated by hashing the designated public opinion information using the public key of the committer and adding a random blinding factor. The proof is used to verify the authenticity of the commitment. The proof uses the proof key, private key and random blinding factor owned by the committer to place the commitment into a proof generation function for secondary encryption and packaging, which is used for privacy verification on the blockchain without disclosing specific public opinion information.

[0016] In certain embodiments, in step S5, the verification method is to utilize the proof transmitted by the off-chain committer, and to verify the additional input parameters claimed by the committer using a defined verification key in a verification function, thereby providing a result that reflects whether the committer's commitment is valid and whether the public opinion information is correct and has not been tampered with.

[0017] The present invention has the following beneficial effects: The present invention is that the notary department stores the information obtained from the information subject in a trusted data set that is not open to the public, extracts the identity information about the information subject from this trusted data set, and uses this identity information to generate a corresponding anonymous information subject. The notary department will use the identity of the anonymous information subject as an agent of the information subject to submit the commitment and proof of the public opinion evidence information that needs to be uploaded to the smart contract for verification. After the verification is legal, the public opinion evidence information will be added to the public opinion evidence information main chain for safekeeping. The present invention ensures that except for the core information related to the public opinion evidence information of the information subject that is used to record on the chain, the rest of the information is safely stored, thereby ensuring the security and privacy of the subject information from a technical perspective. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a flowchart of the steps of the privacy protection method of public opinion evidence information based on blockchain;

[0019] Figure 2 It is a flowchart of the privacy protection method of public opinion evidence information based on blockchain. DETAILED DESCRIPTION

[0020] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0021] The privacy protection method of public opinion evidence information based on blockchain provided by the present invention has the following specific technical solutions:

[0022] The privacy protection method of public opinion evidence information based on blockchain includes the following steps:

[0023] (1) Define an information subject CIS, which has the information set S that needs to be uploaded = {CIS C , CIS -C}, where CIS C The core information of the information subject (including ID number, mobile phone number, etc.), CIS -C Non-core information belonging to the information subject (including gender, age, etc.).

[0024] (2) There is a notary department (ND), which is responsible for receiving the information set S from the CIS. After receiving the information set S, the notary department will store it in the trusted data set T kept by the government department through an internal signature. This process can be expressed as the following formula:

[0025] S→ND:Sig(S,NDid)→T

[0026] Among them, ND idIt is the department identification used by the notary department for signing, and then it is submitted to the trusted data set T for verification. After the verification is passed, the signature information is saved.

[0027] (3) After the information is stored, if necessary, the information set S of the N information subjects stored needs to be i Different core information in CIS Ci Extract and construct the anonymous information subject identity AIS i , use this anonymous identity to upload public opinion evidence information to the chain, where i∈{1, 2, ..., N}. This ensures the identity security of the information subject to a certain extent. With the anonymity of the information subject, the public opinion evidence information uploaded to the chain can then be securely protected.

[0028] (4) For an anonymous information subject AIS, it has encrypted public opinion evidence information m that needs to be stored on the chain. In order to prevent m from being leaked, AIS needs to perform privacy encapsulation on the encrypted public opinion evidence information m, that is, only submit the public opinion evidence commitment Mcom, proof Mproof and related encrypted input information when interacting with the on-chain contract. The formula for constructing the public opinion evidence information m commitment Mcom and proof Mproof is as follows:

[0029] Mcom=H(m|pb|r)

[0030] The meaning of the above formula is to concatenate m, pb, and r and then perform hash operations to generate a public opinion evidence commitment Mcom in a basic encrypted state, so that the commitment has a privacy effect, which is convenient for the subsequent verification of the correctness and legality of m without disclosing the specific public opinion evidence information m. The pb in the calculation formula for generating the commitment is the public key used by the anonymous information subject AIS when submitting the commitment, r is a random number, and H() represents a hash function that hashes the internal numerical information. The commitment of public opinion evidence information is similar to the external announcement of the anonymous information subject, indicating that he has uploaded a piece of public opinion information.

[0031] Mproof=P(p AIS , (m, Mcom), (pr, r))

[0032] At the same time, in order to verify the authenticity of the commitment, AIS also needs to use a set of private key pairs (pr, r) and a proof key p AIS In order to provide a proof to the contract for verification, namely Mproof. The meaning of the above formula is to generate a proof Mproof for verification based on the previously generated commitment Mcom, and to encrypt and encapsulate Mcom twice through the proof key and private key, so as to facilitate the privacy verification of the smart contract on the chain without leaking specific public opinion information. AISIt will be stored in the device of the anonymous information subject off-chain, while the external P() function method is a proof generation function that generates a proof through the specified private key pair (pr, r) and the proof key p AIS Bytes of data are used to generate proof of public opinion information commitment Mcom to facilitate contract code verification

[0033] (5) The specific smart contract on the chain will take the commitment proof Mproof and related input parameters inputs from the transmission channel and verify them with the verification key vk according to the following formula

[0034] result=verify(Mproof, inputs, vk)

[0035] If the verification is legal, the encrypted public opinion evidence information will be submitted to the public opinion evidence information blockchain for storage to ensure that the information is not tampered with and facilitate correct public opinion decisions in the future.

[0036] To summarize, in the present invention, the subject identity of the evidence information is anonymous, and the public opinion evidence information is encrypted throughout the process of circulation within the system. In the process of submitting public opinion information, the external representation is that an anonymous information subject uploads an encrypted public opinion information to the main chain of the public opinion evidence information. However, external unrelated personnel will not know the specific content of the uploaded public opinion evidence information, nor will they know who uploaded it, because the true identity of the information subject has been concealed before uploading, thereby ensuring that except for the core information related to the public opinion evidence information of the information subject that is used to record on the chain, the rest of the information is safely stored, thereby ensuring the security and privacy of the subject information from a technical perspective.

[0037] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. The present invention is not limited to the above examples. Any changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A privacy protection method for public opinion evidence information based on blockchain, characterized in that: The steps include: S1, setting an information subject, wherein the information subject has an information set to be uploaded, and the information set includes core information and non-core information; S2, the notary department receives the information set in step S1, and stores the information set in step S1 into a trusted data set kept by the government department through an internal signature; S3, after the information is stored, the core information in the information set of one or more stored information subjects is extracted to construct an anonymous information subject, and the identity of the anonymous information subject is used to perform the on-chain operation of the public opinion evidence information; S4, the anonymous information subject in step S3 has the encrypted public opinion evidence information, and performs privacy encapsulation on the encrypted public opinion evidence information, and constructs a commitment and proof of the encrypted public opinion evidence information; S5, the smart contract on the blockchain takes the commitment, proof and related input parameters from the transmission channel for verification. After the verification is legal, the public opinion evidence information is added to the public opinion evidence information main chain for safekeeping; In step S4, the privacy encapsulation is to submit only the commitment, proof and related encrypted input information of the public opinion evidence when interacting with the smart contract on the chain; In step S4, the commitment is used for the anonymous information subject to announce to the outside that a piece of public opinion information has been uploaded. The commitment is generated by hashing the designated public opinion information through the public key of the committer and adding a random blinding factor. The proof is used to verify the authenticity of the commitment. The proof is used by the committer's proof key, private key and random blinding factor to put the commitment into the proof generation function for secondary encryption and packaging, which is used for privacy verification on the blockchain without leaking specific public opinion information.

2. According to the privacy protection method of public opinion evidence information based on blockchain according to claim 1, it is characterized in that: In step S1, the core information includes ID number and mobile phone number, and the non-core information includes gender and age.

3. According to the privacy protection method of public opinion evidence information based on blockchain in claim 1, it is characterized in that: In step S2, the internal signature is a department identification used by the notary department for signing, and is verified by the trusted data set. After the verification is passed, the internal signature is saved as information.

4. According to the privacy protection method of public opinion evidence information based on blockchain in claim 1, it is characterized in that: In step S5, the verification method is to use the proof transmitted by the off-chain commitment party, and verify the additional input parameters claimed by the commitment party using the defined verification key in the verification function, and give a result that can reflect whether the commitment of the commitment party is valid and whether the public opinion information is correct and has not been tampered with.

Images