Traceable privacy protection method and system for crowd sensing

Abstract

The invention discloses a traceable privacy protection method and system for crowd sensing. The method comprises the following steps: step 1, initializing a system; 2, a data demander registers; step 3, establishing a task group; 4, submitting the collected data; and 5, tracing the user. According to the invention, the block chain technology and the group signature technology are combined, so that the problem of user privacy leakage in the traditional block chain traceability process is solved. The group signature allows the user to participate anonymously in the transaction, and the unforgeability and traceability of the signature are ensured at the same time. While the privacy of the user is protected, the malicious behavior can be effectively traced. When dispute occurs or auditing is needed, an auditing party can track the signature under the condition that privacy of other users is not leaked, and accuracy and fairness of source tracing are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field related to blockchain, and in particular to a traceable privacy protection method and system for crowd intelligence perception. Background Art

[0002] Crowd perception uses sensor networks and data fusion technology combined with crowdsourcing ideas to collect and process a large amount of perception data in real time, improving the comprehensiveness and accuracy of the data. The combination of blockchain can effectively alleviate the shortcomings of traditional crowd perception, such as centralization, low transparency, and incomplete trust. Crowdsourcing requires a large number of participants, who will upload sensitive information such as identity and location. Blockchain can provide users with limited privacy protection. The introduction of zero-knowledge proof, differential privacy, and homomorphic encryption technology can enhance the privacy strength on the chain, but at the same time increase the difficulty of data traceability.

[0003] The inherent traceability of blockchain has important practical significance for improving the security and reliability of various types of information in modern society. By recording and tracking the progress of specific projects or information, blockchain ensures the legitimacy and authenticity of each transaction throughout the life cycle. However, there is a risk of privacy leakage in the traceability process, so it is necessary to ensure the privacy and traceability of the data on the chain at the same time. In addition, the traceability of blockchain provides technical support for blockchain auditing. However, due to the low transparency of the audit process and the low effectiveness of the current audit, it is necessary to increase the public participation in the audit process.

[0004] In order to coordinate the traceability and privacy of blockchain under crowdsourcing and improve the transparency of on-chain auditing, this application is based on blockchain technology and is applied to the scenario of crowd intelligence perception. It integrates group signature and secret sharing technology. Without destroying the privacy of data, it can realize the traceability audit of malicious behavior, improve the transparency of the on-chain auditing process, protect user rights and interests and promote industry development. Summary of the invention

[0005] The purpose of the present invention is to propose a traceable privacy protection method and system for crowd intelligence perception, which integrates blockchain, group signature, and secret sharing technology, and has the characteristics of decentralization, data credibility, data privacy, traceability, and audit transparency, thereby constructing a traceable privacy protection method for crowd intelligence perception to improve the blockchain and crowd intelligence perception environment.

[0006] To achieve the purpose of the present invention, the technical solution provided by the present invention is specifically as follows:

[0007] First aspect

[0008] This application provides a traceable privacy protection method for crowd intelligence perception, including the following steps:

[0009] Step 1: System initialization: deploy the underlying blockchain network and the key generation function. The auditor completes the authentication and initializes the behavior record list of users and data demanders.

[0010] Step 2: Data demander registration: Data demanders need to interact with the auditors, register and authenticate; generate an on-chain identifier, further set specific task requirements and package them, and send them to the auditors. The auditors verify the credibility of the tasks and publish them on the chain;

[0011] Step 3: Task group formation: On-chain users who intend to perform group intelligence perception tasks register. Users use their own key pairs to interact with the auditor through algorithms, complete sensitive data protection and data desensitization operations, and update records. The contract and the auditor jointly grant the on-chain user group permissions and auxiliary supervision permissions;

[0012] Step 4: Submission of collected data: Participants who have completed task data collection will sign the collected data in a group without disclosing personal information, and send it to the data demander while backing it up on the blockchain; the data demander uses the group public key to verify the validity of the data, and all roles cannot be associated with the data collector and the submitted data;

[0013] Step 5: User tracing: When the data collector or data collector has doubts during the activity, he / she initiates a request to the auditor and attaches his / her own identification information for identity confirmation; the identity information is verified by signature to see if it is consistent with the information at the time of initialization. After the verification is passed, the on-chain contract sends an audit request to all users in the group. Using the idea of ​​secret sharing, when the number of people exceeds the threshold, the key of the opener can be restored, and then the group administrator key can be used to unlock the record list containing complete information, completing the tracing of activity data and user identity.

[0014] Second aspect

[0015] Corresponding to the above method, the present invention also provides a traceable privacy protection system for crowd intelligence perception, comprising the following units: an initialization unit, a demander registration unit, a task group formation unit, a data submission unit, and a tracing unit;

[0016] The initialization unit is used for system initialization: deploying the underlying blockchain network and the key generation function, the auditor completes the authentication and initializes the behavior record list of the user and the data demander;

[0017] The demander registration unit is used for data demander registration: the data demander needs to interact with the auditor, register and authenticate; generate an on-chain identifier, further set specific task requirements and package them, and send them to the auditor. The auditor verifies the credibility of the task and publishes it on the chain;

[0018] The task group formation unit is used for task group formation: on-chain users who intend to perform group intelligence perception tasks register, and the users use their own key pairs to interact with the auditors through algorithms, completing sensitive data protection and data desensitization operations, and updating records. The contract and the auditors jointly grant the on-chain users group permissions and auxiliary supervision permissions;

[0019] The data submission unit is used to collect data submission: the participants who have completed the task data collection will group sign the collected data without disclosing personal information, send it to the data demander and back it up on the blockchain; the data demander uses the group public key to verify the validity of the data, and all roles cannot be associated with the data collector and the submitted data;

[0020] The tracing unit is used for user tracing: when a data collector or data collector has doubts during an activity, he or she initiates a request to the auditor and attaches his or her own identification information for identity confirmation; the identity information is verified by signature to see if it is consistent with the information at the time of initialization. After the verification is passed, the on-chain contract sends an audit request to all users in the group, using the idea of ​​secret sharing. When the number of people exceeds the threshold, the key of the opener can be restored, and then the group administrator's key can be used to unlock the record list containing complete information, completing the tracing of activity data and user identity.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. This invention solves the problem of user privacy leakage in the traditional blockchain traceability process by combining blockchain technology with group signature technology. Group signature allows users to participate anonymously in transactions while ensuring the unforgeability and traceability of signatures. While protecting user privacy, it can effectively trace malicious behavior. When a dispute occurs or an audit is required, the auditor can track the signature without disclosing the privacy of other users, ensuring the accuracy and fairness of traceability.

[0023] 2. The present invention combines secret sharing technology to make the on-chain audit process more transparent. By storing data in shards and reconstructing it when necessary, the verifiability of the audit process and the integrity of the data are ensured. In the crowd-sensing scenario, the present invention can effectively prevent data tampering and forgery and improve the reliability of audit results. By improving the transparency of on-chain audits, it helps regulatory authorities to effectively supervise blockchain applications, reduce industry risks, and create a safe and reliable network environment for users. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of a method flow chart provided by an embodiment of the present invention;

[0025] Figure 2This is a schematic diagram of the system initialization process in an embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram of the data requester registration process in an embodiment of the present invention;

[0027] Figure 4 A schematic diagram of a participant group formation process in an embodiment of the present invention;

[0028] Figure 5 A schematic diagram of the data collection and submission process in an embodiment of the present invention;

[0029] Figure 6 The figure is a schematic diagram of the user tracing process in an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] Example 1

[0032] like Figure 1 As shown, this embodiment provides a traceable privacy protection method for crowd intelligence perception, including the following steps:

[0033] Step 1: System initialization: deploy the underlying blockchain network to meet the needs of user privacy protection and traceability audit, and deploy the key generation function. The auditor completes the authentication and initializes the behavior record list of users and data demanders to facilitate the thorough investigation of violations;

[0034] like Figure 2 As shown, the step 1 specifically includes the following:

[0035] Step 1.1: Deploy the blockchain network BC. Each time a crowd intelligence sensing task is completed, it needs to be packaged into blocks;

[0036] Step 1.2: Preset the task record structure, including the task number TID and the participant's identity tag Uaddr i , data submission time TT, task hash THash and random number R generation structure TR are task records, where:

[0037] TR={TID:value,Uaddr i :value,TT:value,THash:value,R:value};

[0038] Step 1.3: The task record TR will be attached to the block body generated during the reward distribution process, packaged into blocks, and attached to the end of the blockchain;

[0039] Step 1.4: The auditor AT randomly selects a key parameter u to generate an auditor key pair AK = (APK, ask), where APK is the auditor's public key and ask is the auditor's private key;

[0040] Step 1.5: Pack the auditor authentication information ACT and the auditor public key APK to generate the auditor authentication certificate SCT, where SCT = (APK, ACT). The auditor authentication certificate SCT is used for the identity authentication process when the auditor serves as the group manager GM. The auditor AT becomes the task group manager GM through authentication.

[0041] Step 1.6: The auditor generates the auditor's address Saddr=AddrGene(SPK) based on the auditor's public key SPK;

[0042] Step 1.7: Initialize the data requester list Lr[j] = {Caddr j :value,Tr j :value,c j :value}, and publish the auditor’s address Saddr and data demander list Lr[j] to the chain.

[0043] Step 2: Data demander registration: Data demanders need to interact with auditors to register and authenticate, including verification of demander qualifications, etc., mainly to protect the data security of participants and meet the reliability requirements of the published tasks. Generate an on-chain identifier, further set specific task requirements and package them, and send them to the auditors, who will verify the credibility of the tasks and publish them on the chain;

[0044] like Figure 3 As shown, the step 2 specifically includes the following:

[0045] Step 2.1: The data collection task is set by the data demander DR. Before the collection task is released, the data demander DR needs to interact and register with the auditor AT;

[0046] Step 2.2: The data demander DR randomly selects a key generation parameter τ to generate the data demander key pair RK j =(RPK j ,rsk j ), RPK is the public key of the data demander, rsk j The private key of the data demander;

[0047] Step 2.3: Generate the on-chain identity Caddr based on the public key RPK j , where Caddr j =AddrGene(RPK j );

[0048] Step 2.4: Set TX according to your needs j ,DX j ,LX j And other task requirements, and use the private key rsk j Sign and package the task requirements to generate Tr j , where Tr j ←sign(TX j ,DX j ,LX j ), and {c j ,Caddr j ,RPK j ,Tr j} to AT, where c j It is a reliability certificate for data demanders;

[0049] Step 2.5: The auditor receives {c j ,Caddr j ,RPK j ,Tr j}, using the data demander's public key RPK j Test Tr j If the correctness of the signature is verified, the entry is added to Lr[j], assigned the task number TID, and signed, where (TID|sign({Caddr j ,RPK i ,Tr j},ask)) and publish it on the blockchain.

[0050] Step 3: Task group formation: This step mainly involves the registration of on-chain users who intend to perform group intelligence tasks. Users use their own key pairs to interact with the auditor through algorithms, complete sensitive data protection and data desensitization operations, and update records. The contract and the auditor jointly grant the on-chain user group permissions and auxiliary supervision permissions;

[0051] like Figure 4 As shown, the step 3 specifically includes the following:

[0052] Step 3.1: After the task is released, the auditor AT builds a task group for the task numbered TID, and the auditor AT becomes the group manager GM;

[0053] Step 3.2: Generate a group registration key pair CK = (CPK, csk), where CPK is the public key for group registration, which is used by participants to join the group, and csk is the private key for group registration, which is visible only to the administrator GM;

[0054] Step 3.3, initialize the member list Lu[i]:

[0055] Lu[i]={Uaddr:value,UPK:value,usg i :value,HashData i :value,u i :value}, which contains information that can be traced back to the user's real identity and is invisible to all roles until the key is restored;

[0056] Step 3.4: Set the opener traceability key pair OK = (OPK, osk), and the task group manager GM selects two keys that meet large prime numbers p and q, select a generator g of order q in GF(p);

[0057] Step 3.5: Set up traceability keys This key is the opener key, which can be created by any The secrets jointly recovered by members are used to assist group managers in tracing and improve group member participation; Generate a group key pair (OPK, osk), publish the opener public key OPK and keep osk invisible;

[0058] Step 3.6: For any group of m members to be able to compute the secret, compute as well as Optional stk i And calculate according to Calculate UT i , (SPK i ,UT i ) is sent to the traceability group; at the same time, the selection of parameters should satisfy that m and more members cannot pass f i (0)(modq), group public key GK, user public key UPK i and (SPK i ,UT i ) Conspire to obtain secret parameters of the system;

[0059] Step 3.7: ID i With x i For every future participant i The system selects the key and identity authentication of m members and constructs the Lagrange interpolation theorem Also check f i (0)! = 0, if true, reselect the identity ID i With key x i ; if it is not established, then take the one that does not satisfy the current The t+1th pair of different numbers, where ID t+1 ∈Z q ,xt+1 ∈Z q And construct m polynomials f with the first m-1 numbers i (x)(i=1,2,……,t+1), all opener key fragments are not zero and are not equal to each other, and any secret F sum mod q is not zero; construction Polynomial in So we can see that the group tracing secret is The key for tracing is The group tracing public key is OPK=g f(0) mod p(i=1,2,…,n);

[0060] Step 3.8: For each on-chain user u i ∈U, users who want to participate in the crowd intelligence perception task need to first register to become data collectors DC; specifically, users generate personal key pairs UK i :(UPK i ,usk i );

[0061] Step 3.9: Data collector DC uses the public key UPK i Generate on-chain identity Uaddr i , where Uaddr i =AddrGene(UPK i );

[0062] Step 3.10: User public key UPK i 、User ID Uaddr i And user sensitive information i Combination generates structure UrAsk i , called a registration request, where UrAsk i ={UPK i ,Uaddri,u i};

[0063] Step 3.11: Send a registration request UrAsk through a secure channel i , and append usk i Interact with the group registration public key CPK and group administrator GM;

[0064] Step 3.12: After verification, grant the user group authority and distribute the group key gsk i and the opener part key osk i , to give users the power to sign and assist in supervision, and update the list Lu[i] at the same time.

[0065] Step 4: Submission of collected data: Participants who have completed task data collection will sign the collected data in a group without disclosing personal information, and send it to the data demander while backing it up on the blockchain; the data demander uses the group public key to verify the validity of the data, and all roles cannot be associated with the data collector and the submitted data;

[0066] like Figure 5 As shown, the step 4 specifically includes the following:

[0067] Step 4.1: The data submission stage after participant screening involves many participants;

[0068] Step 4.2: Participants collect the data required for the task and enter the collection time in UTX i 、Collection location UDX i And collect data ULX i Various types of data are encapsulated into a structure UTr i , called submitting collected data, where UTr i ={UTX i ,UDX i ,ULX i};

[0069] Step 4.3: The submitter attaches the task number TID and generates a new structure Ua i , called submitted data: Ua i ={TID,UTr i};

[0070] Step 4.4: Participants use the group private key gsk i Signature get sign(Ua i ,gsk i ) and sent to the data demander DR;

[0071] Step 4.5: Data demander DR verifies whether Uaddr i ∈Lu[i];

[0072] Step 4.6: Calculation Let R = R i , and generate a signature (R, a, r) ​​to verify the validity of the signature and authenticate the sender's identity. i )} is sent to the chain for verification.

[0073] Step 5: User tracing: When the data collector or data collector has doubts during the activity, he / she initiates a request to the auditor and attaches his / her own identification information for identity confirmation; the identity information is verified by signature to see if it is consistent with the information at the time of initialization. After the verification is passed, the on-chain contract sends an audit request to all users in the group, using the idea of ​​secret sharing. When the number of people exceeds the threshold, the key of the opener can be recovered, and then the group administrator's key can be used to unlock the record list containing complete information, completing the tracing of activity data and user identity.

[0074] like Figure 6 As shown, the step 5 specifically includes the following:

[0075] Step 5.1: Users with traceability requirements include data collectors DC and data demanders DR;

[0076] Step 5.2: When the DC does not approve of the bonus or score it receives, it needs to obtain relevant proof. It can search the task group administrator GM on the chain through the task ID TID on the chain;

[0077] Step 5.3: The group manager GM receives the user's identity information u i 、Tag Uaddr i And the signature information of the user and verify the correctness of the user's identity information. At the same time, initiate an opener key recovery request to the group users to recover the opener key osk;

[0078] Step 5.4: If the verification is successful, the member's relevant proof i Send to DC;

[0079] Step 5.5: If the application is initiated by the data demander DR, verify c i Correctness of identity;

[0080] Step 5.6: If verification is passed, request to restore the opener key osk and group signature δ i , the group member list Lu generates the signature δ i The user entry Lu[i] is also based on c j The request made sends the associated proof ρ.

[0081] Example 2

[0082] Corresponding to the above method, this embodiment provides a traceable privacy protection system for crowd intelligence perception, including the following units: an initialization unit, a demander registration unit, a task group formation unit, a data submission unit, and a tracing unit;

[0083] The initialization unit is used for system initialization: deploying the underlying blockchain network and the key generation function, the auditor completes the authentication and initializes the behavior record list of the user and the data demander;

[0084] The demander registration unit is used for data demander registration: the data demander needs to interact with the auditor, register and authenticate; generate an on-chain identifier, further set specific task requirements and package them, and send them to the auditor. The auditor verifies the credibility of the task and publishes it on the chain;

[0085] The task group formation unit is used for task group formation: on-chain users who intend to perform group intelligence perception tasks register, and the users use their own key pairs to interact with the auditors through algorithms, completing sensitive data protection and data desensitization operations, and updating records. The contract and the auditors jointly grant the on-chain users group permissions and auxiliary supervision permissions;

[0086] The data submission unit is used to collect data submission: the participants who have completed the task data collection will group sign the collected data without disclosing personal information, send it to the data demander and back it up on the blockchain; the data demander uses the group public key to verify the validity of the data, and all roles cannot be associated with the data collector and the submitted data;

[0087] The tracing unit is used for user tracing: when a data collector or data collector has doubts during an activity, he or she initiates a request to the auditor and attaches his or her own identification information for identity confirmation; the identity information is verified by signature to see if it is consistent with the information at the time of initialization. After the verification is passed, the on-chain contract sends an audit request to all users in the group, using the idea of ​​secret sharing. When the number of people exceeds the threshold, the key of the opener can be restored, and then the group administrator's key can be used to unlock the record list containing complete information, completing the tracing of activity data and user identity.

[0088] Preferably, the initialization unit is specifically used to perform the following steps:

[0089] Step 1.1: Deploy the blockchain network BC. Each time a crowd intelligence sensing task is completed, it needs to be packaged into blocks;

[0090] Step 1.2: Preset the task record structure, including the task number TID and the participant's identity tag Uaddr i , data submission time TT, task hash THash and random number R generation structure TR are task records, where:

[0091] TR={TID:value,Uaddr i :value,TT:value,THash:value,R:value};

[0092] Step 1.3: The task record TR will be attached to the block body generated during the reward distribution process, packaged into blocks, and attached to the end of the blockchain;

[0093] Step 1.4: The auditor AT randomly selects a key parameter u to generate an auditor key pair AK = (APK, ask), where APK is the auditor's public key and ask is the auditor's private key;

[0094] Step 1.5: Pack the auditor authentication information ACT and the auditor public key APK to generate the auditor authentication certificate SCT, where SCT = (APK, ACT). The auditor authentication certificate SCT is used for the identity authentication process when the auditor serves as the group manager GM. The auditor AT becomes the task group manager GM through authentication.

[0095] Step 1.6: The auditor generates the auditor's address Saddr=AddrGene(SPK) based on the auditor's public key SPK;

[0096] Step 1.7: Initialize the data requester list Lr[j] = {Caddr j :value,Tr j :value,c j :value}, and publish the auditor’s address Saddr and data demander list Lr[j] to the chain.

[0097] Preferably, the demander registration unit is specifically configured to perform the following steps:

[0098] Step 2.1: The data collection task is set by the data demander DR. Before the collection task is released, the data demander DR needs to interact and register with the auditor AT;

[0099] Step 2.2: The data demander DR randomly selects a key generation parameter τ to generate the data demander key pair RK j =(RPK j ,rsk j ), RPK is the public key of the data demander, rsk j The private key of the data demander;

[0100] Step 2.3: Generate the on-chain identity Caddr based on the public key RPK j , where Caddr j =AddrGene(RPK j );

[0101] Step 2.4: Set TX according to your needs j ,DX j ,LX jMultiple task requirements, and use the private key rsk j Sign and package the task requirements to generate Tr j , where Tr j ←sign(TX j ,DX j ,LX j ), and {c j ,Caddr j ,RPK j ,Tr j} to AT, where c j It is a reliability certificate for data demanders;

[0102] Step 2.5: The auditor receives {c j ,Caddr j ,RPK j ,Tr j}, using the data demander's public key RPK j Test Tr j If the correctness of the signature is verified, the entry is added to Lr[j], assigned the task number TID, and signed, where (TID|sign({Caddr j ,RPK i ,Tr j},ask)) and publish it on the blockchain.

[0103] Preferably, the task group forming unit is specifically used to perform the following steps:

[0104] Step 3.1: After the task is released, the auditor AT builds a task group for the task numbered TID, and the auditor AT becomes the group manager GM;

[0105] Step 3.2: Generate a group registration key pair CK = (CPK, csk), where CPK is the public key for group registration, which is used by participants to join the group, and csk is the private key for group registration, which is visible only to the administrator GM;

[0106] Step 3.3, initialize the member list Lu[i]:

[0107] Lu[i]={Uaddr:value,UPK:value,usg i :value,HashData i :value,u i :value}, which contains information that can be traced back to the user's real identity and is invisible to all roles until the key is restored;

[0108] Step 3.4: Set the opener traceability key pair OK = (OPK, osk), and the task group manager GM selects two keys that meet large prime numbers p and q, select a generator g of order q in GF(p);

[0109] Step 3.5: Set up traceability keys This key is the opener key, which can be created by any The secrets jointly recovered by members are used to assist group managers in tracing and improve group member participation; Generate a group key pair (OPK, osk), publish the opener public key OPK and keep osk invisible;

[0110] Step 3.6: For any group of m members to be able to compute the secret, compute as well as Optional stk i And calculate according to Calculate UT i , (SPK i ,UT i ) is sent to the traceability group; at the same time, the selection of parameters should satisfy that m and more members cannot pass f i (0)(modq), group public key GK, user public key UPK i and (SPK i ,UT i ) Conspire to obtain secret parameters of the system;

[0111] Step 3.7: ID i With x i For every future participant i The system selects the key and identity authentication of m members and constructs the Lagrange interpolation theorem Also check f i (0)! = 0, if true, reselect the identity ID i With key x i ; if it is not established, then take the one that does not satisfy the current The t+1th pair of different numbers, where ID t+1 ∈Z q ,x t+1 ∈Z q And construct m polynomials f with the first m-1 numbers i (x)(i=1,2,……,t+1), all opener key fragments are not zero and are not equal to each other, and any secret F sum mod q is not zero; construction Polynomial in So we can see that the group tracing secret is The key for tracing is The group tracing public key is OPK=g f(0) mod p(i=1,2,…,n);

[0112] Step 3.8: For each on-chain user u i ∈U, users who want to participate in the crowd intelligence perception task need to first register to become data collectors DC; specifically, users generate personal key pairs UK i :(UPK i ,usk i );

[0113] Step 3.9: Data collector DC uses the public key UPK i Generate on-chain identity Uaddr i , where Uaddr i =AddrGene(UPK i );

[0114] Step 3.10: User public key UPK i 、User ID Uaddr i And user sensitive information i Combination generates structure UrAsk i , called a registration request, where UrAsk i ={UPK i ,Uaddri,u i};

[0115] Step 3.11: Send a registration request UrAsk through a secure channel i , and append usk i Interact with the group registration public key CPK and group administrator GM;

[0116] Step 3.12: After verification, grant the user group authority and distribute the group key gsk i and the opener part key osk i , to give users the power to sign and assist in supervision, and update the list Lu[i] at the same time.

[0117] The optional implementation modes of the embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above implementation modes. Within the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical scheme of the embodiments of the present invention, and these simple modifications all belong to the protection scope of the embodiments of the present invention.

Claims

1. A traceable privacy protection method for crowd intelligence perception, characterized in that: The steps include: Step 1: System initialization: deploy the underlying blockchain network and the key generation function. The auditor completes the authentication and initializes the behavior record list of users and data demanders. Step 2: Data demander registration: Data demanders need to interact with the auditor to register and authenticate; Generate an on-chain identifier, further set specific task requirements and package them, and send them to the auditor, who will verify the credibility of the task and publish it on the chain; Step 3: Task group formation: On-chain users who intend to perform group intelligence perception tasks register. Users use their own key pairs to interact with the auditor through algorithms, complete sensitive data protection and data desensitization operations, and update records. The contract and the auditor jointly grant the on-chain user group permissions and auxiliary supervision permissions; Step 4: Submission of collected data: Participants who have completed task data collection will sign the collected data in a group without disclosing personal information, send it to the data demander and back it up on the blockchain; The data demander uses the group public key to verify the validity of the data. No role can be associated with the data collector or the submitted data; Step 5: User tracing: When the data collector or data collector has doubts during the activity, he / she initiates a request to the auditor and attaches his / her own identification information for identity confirmation; the identity information is verified by signature to see if it is consistent with the information at the time of initialization. After the verification is passed, the on-chain contract sends an audit request to all users in the group, using the idea of ​​secret sharing. When the number of people exceeds the threshold, the key of the opener can be recovered, and then the group administrator's key can be used to unlock the record list containing complete information, completing the tracing of activity data and user identity.

2. According to claim 1, a traceable privacy protection method for crowd intelligence perception is characterized in that: The step 1 specifically includes the following: Step 1.1: Deploy the blockchain network BC. Each time a crowd intelligence sensing task is completed, it needs to be packaged into blocks; Step 1.2: Preset the task record structure, including the task number TID and the participant's identity tag Uaddr i , data submission time TT, task hash THash and random number R generation structure TR are task records, where: TR={TID:value,Uaddri:value,TT:value,THash:value,R:value}; Step 1.3: The task record TR will be attached to the block body generated during the reward distribution process, packaged into blocks, and attached to the end of the blockchain; Step 1.4: The auditor AT randomly selects a key parameter u to generate an auditor key pair AK = (APK, ask), where APK is the auditor's public key and ask is the auditor's private key; Step 1.5: Pack the auditor authentication information ACT and the auditor public key APK to generate the auditor authentication certificate SCT, where SCT = (APK, ACT). The auditor authentication certificate SCT is used for the identity authentication process when the auditor serves as the group manager GM. The auditor AT becomes the task group manager GM through authentication. Step 1.6: The auditor generates the auditor's address Saddr=AddrGene(SPK) based on the auditor's public key SPK; Step 1.7: Initialize the data requester list Lr[j] = {Caddr j :value,Tr j :value,c j :value}, and publish the auditor’s address Saddr and data demander list Lr[j] to the chain.

3. According to claim 2, a traceable privacy protection method for crowd intelligence perception is characterized in that: The step 2 specifically includes the following: Step 2.1: The data collection task is set by the data demander DR. Before the collection task is released, the data demander DR needs to interact and register with the auditor AT; Step 2.2: The data demander DR randomly selects a key generation parameter τ to generate the data demander key pair RK j =(RPK j ,rsk j ), RPK is the public key of the data demander, rsk j The private key of the data demander; Step 2.3: Generate the on-chain identity Caddr based on the public key RPK j , where Caddr j =AddrGene(RPK j ); Step 2.4: Set TX according to your needs j ,DX j ,LX j Multiple task requirements, and use the private key rsk j Sign and package the task requirements to generate Tr j , where Tr j ←sign(TX j ,DX j ,LX j ), and {c j ,Caddr j ,RPK j ,Tr j } to AT, where cj is the reliability certificate of the data demander; Step 2.5: The auditor receives {c j ,Caddr j ,RPK j ,Tr j }, using the data demander's public key RPK j Test Tr j If the correctness of the signature is verified, the entry is added to Lr[j], assigned the task number TID, and signed, where (TID|sign({Caddr j ,RPK i ,Tr j },ask)) and publish it on the blockchain.

4. According to claim 3, a traceable privacy protection method for crowd intelligence perception is characterized in that: The step 3 specifically includes the following: Step 3.1: After the task is released, the auditor AT builds a task group for the task numbered TID, and the auditor AT becomes the group manager GM; Step 3.2: Generate a group registration key pair CK = (CPK, csk), where CPK is the public key for group registration, which is used by participants to join the group, and csk is the private key for group registration, which is visible only to the administrator GM; Step 3.3, initialize the member list Lu[i]: Lu[i]={Uaddr:value,UPK:value,usgi:value,HashData i :value,u i :value}, which contains information that can be traced back to the user's real identity and is invisible to all roles until the key is restored; Step 3.4: Set the opener traceability key pair OK = (OPK, osk), and the task group manager GM selects two keys that meet large prime numbers p and q, select a generator g of order q in GF(p); Step 3.5: Set up traceability keys This key is the opener key, which can be created by any The secrets jointly recovered by members are used to assist group managers in tracing and improve group member participation; Generate a group key pair (OPK, osk), publish the opener public key OPK and keep osk invisible; Step 3.6: For any group of m members to be able to compute the secret, compute as well as Optional stk i And calculate according to Calculate UT i , (SPK i ,UT i ) is sent to the traceability group; at the same time, the selection of parameters should satisfy that m and more members cannot pass f i (0)(mod q), group public key GK, user public key UPK i and (SPK i ,UT i ) Conspire to obtain secret parameters of the system; Step 3.7: ID i With x i For every future participant i The system selects the key and identity authentication of m members and constructs the Lagrange interpolation theorem Also check f i (0)! = 0, if true, reselect the identity ID i With key x i ; if it is not established, then take the one that does not satisfy the current The t+1th pair of different numbers, where ID t+1 ∈Z q ,x t+1 ∈Z q And construct m polynomials with the first m-1 numbers All opener key fragments are non-zero and not equal to each other, and any secret F sum mod q is not zero; structure Polynomial in So we can see that the group tracing secret is The key for tracing is The group tracing public key is OPK=g f(0) mod p(i=1,2,…,n); Step 3.8: For each on-chain user u i ∈U, users who want to participate in the crowd intelligence perception task need to first register to become data collectors DC; specifically, users generate personal key pairs UK i :(UPK i ,usk i ); Step 3.9: Data collector DC uses the public key UPK i Generate on-chain identity Uaddr i , where Uaddr i =AddrGene(UPK i ); Step 3.10: User public key UPK i 、User ID Uaddr i And user sensitive information i Combination generates structure UrAsk i , called a registration request, where UrAsk i ={UPK i ,Uaddr i ,u i }; Step 3.11: Send a registration request UrAsk through a secure channel i , and append usk i Interact with the group registration public key CPK and group administrator GM; Step 3.12: After verification, grant the user group authority and distribute the group key gsk i and the opener part key osk i , to give users the power to sign and assist in supervision, and update the list Lu[i] at the same time.

5. According to claim 4, a traceable privacy protection method for crowd intelligence perception is characterized in that: The step 4 specifically includes the following: Step 4.1: The data submission stage after participant screening involves many participants; Step 4.2: Participants collect the data required for the task and enter the collection time in UTX i 、Collection location UDX i And collect data ULX i Various types of data are encapsulated into a structure UTr i , called submitting collected data, where UTr i ={UTX i ,UDX i ,ULX i }; Step 4.3: The submitter attaches the task number TID and generates a new structure Ua i , called submitted data: Ua i ={TID,UTr i }; Step 4.4: Participants use the group private key gsk i Signature get sign(Ua i ,gsk i ) and sent to the data demander DR; Step 4.5: Data demander DR verifies whether Uaddr i ∈Lu[i]; Step 4.6: Calculation Let R = R i , and generate a signature (R, a, r) ​​to verify the validity of the signature and authenticate the sender's identity. i )} is sent to the chain for verification.

6. According to claim 5, a traceable privacy protection method for crowd intelligence perception is characterized in that: The step 5 specifically includes the following: Step 5.1: Users with traceability requirements include data collectors DC and data demanders DR; Step 5.2: When the DC does not approve of the bonus or score it receives, it needs to obtain relevant proof. It can search the task group administrator GM on the chain through the task ID TID on the chain; Step 5.3: GM receives the user's identity information u i , label Uaddri and the user's signature information and verify the correctness of the user's identity information. At the same time, initiate an opener key recovery request to the group users to recover the opener key osk; Step 5.4: If the verification is successful, the member's relevant proof i Send to DC; Step 5.5: If the data requester DR initiates the application, verify c i Correctness of identity; Step 5.6: If verification is passed, request to restore the opener key osk and group signature δ i , the group member list Lu generates the signature δ i The user entry Lu[i] is also based on c j The request made sends the associated proof ρ.

7. A traceable privacy protection system for crowd intelligence perception, characterized in that: It includes the following units: initialization unit, demander registration unit, task group formation unit, data submission unit, and traceability unit; The initialization unit is used for system initialization: deploying the underlying blockchain network and the key generation function, the auditor completes the authentication and initializes the behavior record list of the user and the data demander; The demander registration unit is used for data demander registration: the data demander needs to interact with the auditor to register and authenticate; Generate an on-chain identifier, further set specific task requirements and package them, and send them to the auditor, who will verify the credibility of the task and publish it on the chain; The task group formation unit is used for task group formation: on-chain users who intend to perform group intelligence perception tasks register, and the users use their own key pairs to interact with the auditors through algorithms, completing sensitive data protection and data desensitization operations, and updating records. The contract and the auditors jointly grant the on-chain users group permissions and auxiliary supervision permissions; The data submission unit is used to collect data submission: the participants who have completed the task data collection will group sign the collected data without disclosing personal information, send it to the data demander and back it up on the blockchain at the same time; The data demander uses the group public key to verify the validity of the data. No role can be associated with the data collector or the submitted data; The tracing unit is used for user tracing: when a data collector or data collector has doubts during an activity, he or she initiates a request to the auditor and attaches his or her own identification information for identity confirmation; the identity information is verified by signature to see if it is consistent with the information at the time of initialization. After the verification is passed, the on-chain contract sends an audit request to all users in the group, using the idea of ​​secret sharing. When the number of people exceeds the threshold, the key of the opener can be restored, and then the group administrator's key can be used to unlock the record list containing complete information, completing the tracing of activity data and user identity.

8. The traceable privacy protection system for crowd intelligence perception according to claim 7 is characterized in that: The initialization unit is specifically used to perform the following steps: Step 1.1: Deploy the blockchain network BC. Each time a crowd intelligence sensing task is completed, it needs to be packaged into blocks; Step 1.2: Preset the task record structure, including the task number TID and the participant's identity tag Uaddr i , data submission time TT, task hash THash and random number R generation structure TR are task records, where: TR={TID:value,Uaddri:value,TT:value,THash:value,R:value}; Step 1.3: The task record TR will be attached to the block body generated during the reward distribution process, packaged into blocks, and attached to the end of the blockchain; Step 1.4: The auditor AT randomly selects a key parameter u to generate an auditor key pair AK = (APK, ask), where APK is the auditor's public key and ask is the auditor's private key; Step 1.5: Pack the auditor authentication information ACT and the auditor public key APK to generate the auditor authentication certificate SCT, where SCT = (APK, ACT). The auditor authentication certificate SCT is used for the identity authentication process when the auditor serves as the group manager GM. The auditor AT becomes the task group manager GM through authentication. Step 1.6: The auditor generates the auditor's address Saddr=AddrGene(SPK) based on the auditor's public key SPK; Step 1.7: Initialize the data requester list Lr[j] = {Caddr j :value,Tr j :value,c j :value}, and publish the auditor’s address Saddr and data demander list Lr[j] to the chain.

9. The traceable privacy protection system for crowd intelligence perception according to claim 8 is characterized in that: The demand side registration unit is specifically used to perform the following steps: Step 2.1: The data collection task is set by the data demander DR. Before the collection task is released, the data demander DR needs to interact and register with the auditor AT; Step 2.2: The data demander DR randomly selects a key generation parameter τ to generate the data demander key pair RK j =(RPK j ,rsk j ), RPK is the public key of the data demander, rsk j The private key of the data demander; Step 2.3: Generate the on-chain identity Caddr based on the public key RPK j , where Caddr j =AddrGene(RPK j ); Step 2.4: Set TX according to your needs j ,DX j ,LX j Multiple task requirements, and use the private key rsk j Sign and package the task requirements to generate Tr j , where Tr j ←sign(TX j ,DX j ,LX j ), and {c j ,Caddr j ,RPK j ,Tr j } to AT, where c j It is a reliability certificate for data demanders; Step 2.5: The auditor receives {c j ,Caddr j ,RPK j ,Tr j }, using the data demander's public key RPK j Test Tr j If the correctness of the signature is verified, the entry is added to Lr[j], assigned the task number TID, and signed, where (TID|sign({Caddr j ,RPK i ,Tr j },ask)) and publish it on the blockchain.

10. The traceable privacy protection system for crowd intelligence perception according to claim 9 is characterized in that: The task group forming unit is specifically used to perform the following steps: Step 3.1: After the task is released, the auditor AT builds a task group for the task numbered TID, and the auditor AT becomes the group manager GM; Step 3.2: Generate a group registration key pair CK = (CPK, csk), where CPK is the public key for group registration, which is used by participants to join the group, and csk is the private key for group registration, which is visible only to the administrator GM; Step 3.3, initialize the member list Lu[i]: Lu[i]={Uaddr:value,UPK:value,usg i :value,HashData i :value,u i :value}, which contains information that can be traced back to the user's real identity and is invisible to all roles until the key is restored; Step 3.4: Set the opener traceability key pair OK = (OPK, osk), and the task group manager GM selects two keys that meet large prime numbers p and q, select a generator g of order q in GF(p); Step 3.5: Set up traceability keys This key is the opener key, which can be created by any The secrets jointly recovered by members are used to assist group managers in tracing and improve group member participation; Generate a group key pair (OPK, osk), publish the opener public key OPK and keep osk invisible; Step 3.6: For any group of m members to be able to compute the secret, compute as well as Optional stk i And calculate according to Calculate UT i , (SPK i ,UT i ) is sent to the traceability group; at the same time, the selection of parameters should satisfy that m and more members cannot pass f i (0)(mod q), group public key GK, user public key UPK i and (SPK i ,UT i ) Conspire to obtain secret parameters of the system; Step 3.7: ID i With x i For every future participant i The system selects the key and identity authentication of m members and constructs the Lagrange interpolation theorem Also check f i (0)! = 0, if true, reselect the identity ID i With key x i ; if it is not established, then take the one that does not satisfy the current The t+1th pair of different numbers, where ID t+1 ∈Z q ,x t+1 ∈Z q And construct m polynomials f with the first m-1 numbers i (x)(i=1,2,……,t+1), all opener key fragments are not zero and are not equal to each other, and any secret F sum mod q is not zero; structure Polynomial in So we can see that the group tracing secret is The key for tracing is The group tracing public key is OPK=g f(0) mod p(i=1,2,…,n); Step 3.8: For each on-chain user u i ∈U, users who want to participate in the crowd intelligence perception task need to first register to become data collectors DC; specifically, users generate personal key pairs UK i :(UPK i ,usk i ); Step 3.9: Data collector DC uses the public key UPK i Generate on-chain identity Uaddr i , where Uaddr i =AddrGene(UPK i ); Step 3.10: User public key UPK i 、User ID Uaddr i And user sensitive information i Combination generates structure UrAsk i , called a registration request, where UrAsk i ={UPK i ,Uaddr i ,u i }; Step 3.11: Send a registration request UrAsk through a secure channel i , and append usk i Interact with the group registration public key CPK and group administrator GM; Step 3.12: After verification, grant the user group authority and distribute the group key gsk i and the opener part key osk i , to give users the power to sign and assist in supervision, and update the list Lu[i] at the same time.

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