Block chain technology-based review data information security tamper-proofing method

Abstract

The invention discloses a block chain technology-based review data information security tamper-proofing method, and relates to the technical field of information security, the tamper-proofing method comprises the following steps: a data encryption storage step, a data evidence storage step, a trusted computing step and a data verification step, when a computing request is received, the trusted computing step is executed, and the trusted computing step is executed; whether the identity of a requester conforms to the access control strategy is verified through the smart contract, after verification is passed, the smart contract generates a calculation task event, the oracle monitors and captures the event, then a calculation task is transmitted to the trusted execution environment, ciphertext data is obtained in the trusted execution environment and decrypted, and the calculation task is sent to the target server. The method has the advantages that the balance of data privacy protection and integrity verification is realized through a hierarchical architecture combining on-chain evidence storage and off-chain encrypted storage, sensitive review data is stored in an off-chain database in an encrypted form, the security of the review data is improved, the security of the review data is improved, and the security of the review data is improved. Only data fingerprints are recorded on the block chain, data privacy is protected, and data integrity can be verified through the block chain.

Description

Technical Field

[0001] This invention relates to the field of information security technology, specifically to a method for preventing tampering of review data information based on blockchain technology. Background Technology

[0002] With the widespread application of digital review systems, the security and credibility of review data have become critical issues. Review data typically contains sensitive information such as expert scores, review opinions, and review time. This data needs to be protected from malicious tampering to maintain the fairness of the review, while also protecting the privacy of review experts from being leaked. Blockchain technology, due to its decentralized and tamper-proof characteristics, is considered an ideal technology for solving data integrity and traceability. However, directly applying blockchain technology to review data management faces many challenges. The existing technologies mainly include the following types of solutions: The first type is the plaintext on-chain solution, which stores the review data directly or after simple encoding on the blockchain. Due to the transparency and multi-node sharing characteristics of the blockchain, all participating nodes can access the review data, resulting in the leakage of review experts' privacy and exposure of sensitive information. The identity of review experts may be analyzed for correlation, and review opinions may be maliciously used, violating data protection regulations. The second type is a fully encrypted on-chain solution, which uses strong encryption algorithms to encrypt the review data and then stores it on the blockchain. Because the data is stored in full encryption, smart contracts cannot directly process the encrypted data, which makes it impossible to realize automated review statistics and analysis functions, score aggregation calculation, and content-based retrieval, and the system functions are severely limited. The third type is homomorphic encryption scheme, which uses homomorphic encryption algorithm to encrypt the review data and allows calculation operations to be performed in the ciphertext state. However, due to the extremely high computational complexity of homomorphic encryption, the system performance is severely degraded, the calculation time is as long as several hours or even days, the hardware resource requirements are huge, and it is difficult to meet the real-time requirements. Furthermore, none of the existing solutions mentioned above can meet the "right to be forgotten" requirement of data protection regulations such as GDPR. Once data is on the blockchain, it cannot be truly deleted, which raises compliance issues. Therefore, we propose a method for protecting review data from tampering based on blockchain technology. Summary of the Invention

[0003] The purpose of this invention is to provide a method for protecting review data information from tampering based on blockchain technology.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a method for preventing tampering of review data information based on blockchain technology, comprising an anti-tampering method, wherein the anti-tampering method includes the following steps: S1. Data encryption and storage steps: Receive review data, generate a symmetric key to encrypt the review data, and store the encrypted ciphertext data in the off-chain database. S2. Data storage step: Calculate the hash digest of the review data, submit the hash digest, the storage location information of the encrypted data and the access control policy to the blockchain smart contract, and the smart contract records the storage information. S3, Trusted Computing Steps: When a computing request is received, the smart contract verifies whether the requester's identity complies with the access control policy. After successful verification, the smart contract generates a computing task event. The oracle listens for and captures the event, and then the computing task is passed to the trusted execution environment. The encrypted data is obtained and decrypted in the trusted execution environment. After performing the computing operation, the computing result is encrypted, and the encrypted computing result is returned to the smart contract. S4. Data verification step: Verify the integrity of the data in the off-chain database by reading the hash digest recorded on the blockchain.

[0005] As a further aspect of the present invention: the specific process of encrypting the review data in the data encryption and storage step includes: generating an AES encryption key and an initialization vector; The review data is divided into blocks, and data portions that are less than one block are padded. Each data block is then encrypted using AES-CBC mode to generate ciphertext data.

[0006] As a further aspect of the present invention: the access control policy includes authorized user identification, data access time window, and data usage purpose restrictions.

[0007] As a further aspect of the present invention: the trusted execution environment implements isolated computing regions based on hardware security technology, and the computing operations are executed in isolated secure memory regions, where external systems cannot access the data in the secure memory regions.

[0008] As a further aspect of the present invention: the trusted computing step further includes a step of generating a computing proof, wherein the computing proof includes a computing task identifier, a computing result hash value, an execution timestamp, and signature information of a trusted execution environment.

[0009] As a further aspect of the present invention, the anti-tampering method further includes a data destruction step: S5. Receive a data deletion request initiated by an authorized user verified by the smart contract, and verify deletion permission through the smart contract; S6. After verification, locate the encrypted data in the off-chain database based on the evidence storage record on the blockchain; S7. Delete the encrypted data and destroy the corresponding decryption key; S8. Record the data destruction operation on the blockchain and update the status of the evidence record to "destroyed".

[0010] As a further aspect of the present invention: in the data storage step, after the smart contract records the storage information, it also returns the blockchain hash value of the storage transaction to the submitter as a credential for subsequent querying and verification.

[0011] As a further aspect of the present invention: after detecting a computation task event issued by a smart contract, the oracle obtains the task information and transmits it to the application in the trusted execution environment.

[0012] As a further aspect of the present invention: in the data verification step, the verifier determines the data integrity by comparing whether the hash value recalculated after decrypting the off-chain data is consistent with the hash digest recorded on the blockchain.

[0013] As a further aspect of the present invention, the anti-tampering method further includes the step of generating a data destruction certificate, wherein the destruction certificate records the destruction time, the destruction scope (including the data storage location identifier and the corresponding key identifier) ​​and the operator information.

[0014] Compared with the prior art, the beneficial effects of the present invention by adopting the above technical solution are as follows: 1. This invention achieves a balance between data privacy protection and integrity verification through a layered architecture that combines on-chain evidence storage with off-chain encrypted storage. Sensitive review data is stored in encrypted form in an off-chain database, while only data fingerprints are recorded on the blockchain. This protects data privacy while enabling data integrity verification through the blockchain. 2. This invention utilizes Trusted Execution Environment (TEE) technology to achieve privacy-preserving computation, completing data decryption and computation operations in a hardware-isolated secure area. This resolves the contradiction between data privacy and computation availability in traditional solutions and avoids the performance bottleneck of homomorphic encryption schemes. 3. This invention satisfies the "right to be forgotten" requirement of data protection regulations through a controllable destruction mechanism for off-chain data and keys, thus achieving a harmonious balance between the immutability of blockchain and compliance requirements.

[0015] The automated permission management and task scheduling mechanism based on smart contracts improves system security and maintainability, and reduces the risk of human intervention. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall system architecture of the present invention; Figure 2 This is a schematic diagram of the data storage and evidence preservation process of the present invention; Figure 3This is a schematic diagram of the trusted computing execution process of the present invention; Figure 4 This is a schematic diagram of the data destruction process of the present invention. Detailed Implementation

[0017] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings. It should be noted that the description of these embodiments is for the purpose of helping to understand the present invention, but does not constitute a limitation of the present invention.

[0018] Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0019] Example 1 This embodiment provides a method for ensuring the security and tamper-proof nature of review data based on blockchain technology, such as... Figure 2 As shown, it includes the following steps: Step S1: Data Encryption and Storage Steps When review experts submit review data through the application interface layer, the system first encrypts the data, as follows: S11: The system uses a cryptographically secure random number generator to generate a 256-bit AES encryption key Kdata and a 128-bit initialization vector IV. The key is used to encrypt the review data, and the initialization vector is used to ensure that the same plaintext produces different ciphertexts. S12: Divide the review data into blocks according to the AES block size of 128 bits. The review data usually includes fields such as review expert identifier, review object identifier, review score, review comment text, review timestamp, etc. For data parts that are less than one block, use PKCS7 padding to make them full, ensuring that all data blocks have the same length. S13: Use AES-256-CBC mode to encrypt each data block. In CBC mode, the plaintext of the current block is first XORed with the ciphertext of the previous block, and then encrypted to enhance the encryption strength. The first block is XORed with the initialization vector IV and then encrypted to generate ciphertext data Cdata. S14: Store the encrypted ciphertext data Cdata in an off-chain distributed database. The database adopts a sharding storage strategy to improve storage efficiency and access performance. At the same time, assign a unique storage location identifier Locid to each ciphertext data. This identifier contains database node information, sharding index and record primary key. S15: Securely store the encryption key Kdata in the key management system and establish a mapping relationship with the storage location identifier Locid. The key management system uses a hardware security module to protect the security of the key.

[0020] Step S2: Data Storage Procedure After the data is encrypted and stored, the system stores the data on the blockchain: S21: Calculate the SHA-256 hash digest Hdata of the original review data. The hash function has one-way and collision resistance. Any small change in the data will lead to a significant change in the hash value. Therefore, the hash digest can serve as the unique fingerprint of the data. S22: Construct an access control policy that defines which users can access or compute the review data under what conditions. The access control policy includes the following: Authorized user identity list, specifying the user addresses that are allowed to access the data; Data access time window: Sets the valid access period for data. Data usage restrictions stipulate that data can only be used for specific computing tasks. S23: Package the hash digest Hdata, storage location identifier Localid, and access control policy into a storage data package and submit it to the blockchain smart contract; S24: After receiving the evidence storage data packet, the smart contract first verifies the submitter's identity and permissions, and then records the evidence storage information in the blockchain's distributed ledger. The recorded content includes: Data hash digest Hdata; Storage location identifier (Locid); Access control policy; Submitter's address; Evidence timestamp; Data status indicator, initial status is "valid"; S25: Consensus nodes in the blockchain network verify and confirm the notarized transaction, and package the transaction into a new block through the consensus mechanism. Once the transaction is on the chain, it has immutability and traceability. S26: The smart contract returns the blockchain hash value of the notarized transaction to the submitter, which can be used as a credential for subsequent queries and verifications.

[0021] Step S3: Trusted Computing Steps When statistical analysis or other computational processing of the review data is required, a trusted computation process is executed, such as... Figure 3 As shown: S31: Users submit computation requests to smart contracts through the application interface layer. The computation request includes: the storage location identifier of the target data (Locid), the type of computation task (such as scoring statistics, data aggregation, etc.), the configuration of computation parameters, and the identity signature of the requester. S32: After receiving a computation request, the smart contract first performs permission verification. The smart contract reads the access control policy corresponding to the data, checks whether the requester's address is in the authorized user list, verifies whether the current time is within the allowed access time window, and determines whether the computation task type meets the data usage purpose restrictions. S33: If the permission verification fails, the smart contract rejects the computation request and records the access log to prevent unauthorized access. If the verification passes, proceed to the next step. S34: The smart contract generates a computation task Task, which includes information such as task identifier, storage location identifier Localy, computation type and parameters, and signs the task using the smart contract's private key to generate a task signature Sigtask. S35: The oracle service continuously listens for events in smart contracts. When a new computation task event is detected, the oracle obtains the computation task Task and the task signature Sigtask. S36: Oracle calls applications running in a Trusted Execution Environment (TEE). The TEE is an isolated computing region implemented based on hardware security technologies, such as Intel SGX or ARM TrustZone, which can create a secure execution region in an untrusted operating system environment. S37: The TEE application first verifies the integrity and legitimacy of the computation task, using the public key of the smart contract to verify the task signature Sigtask, ensuring that the task was indeed generated by the authorized smart contract and has not been tampered with. S38: After successful verification, the TEE application retrieves the corresponding encrypted data Cdata from the off-chain database based on the storage location identifier Locid in the task. S39: The TEE application obtains the decryption key Kdata from the key management system, and the key transmission process is protected by encryption using a secure channel. S310: In the secure memory area of ​​the TEE, the ciphertext data Cdata is decrypted using the key Kdata to obtain the plaintext review data Dplain. The entire decryption process is carried out in a hardware-isolated environment, and external systems (including operating systems and other unauthorized applications) cannot access the data in the secure memory area of ​​the TEE, thus ensuring the confidentiality of the data. S311: Perform calculation operations in a TEE secure environment. Taking score statistics as an example, if the calculation task is to calculate the average score of multiple review experts, then extract the scores of each expert from the decrypted data, calculate the average score, and perform the calculation operation. For example, if the calculation task is to calculate the average score, then the calculation formula is: Average score = Sum of all scores / Number of review experts. S312: Encrypt the calculation result to generate a new encryption key Kresult. Use this key to encrypt the calculation result with AES to generate the ciphertext result Cresult. S313: TEE generates a computation execution proof, Proofcompute, which contains the following information: The hash value of the calculation result is used to verify the integrity of the result; Execution timestamp, recording the time when the calculation was completed; The TEE's signature information proves that the computation was performed in a trusted environment; Calculate the task identifier and associate it with the original request; S314: TEE applications clear plaintext data and decryption keys from secure memory areas to ensure that sensitive information is not left behind; S315: The oracle submits the encrypted result Cresult and the computational proof Proofcompute to the smart contract; S316: The smart contract verifies the validity of the computation proof, including verifying the TEE signature and checking the rationality of the timestamp. After the verification is passed, the computation result is stored on the blockchain or returned to the requester. S317: Smart contracts return ciphertext of the computation result to the requester or, upon request, decrypt and return plaintext, while providing a computational proof as a trusted credential.

[0022] Step S4: Data Validation Step To ensure that the data stored in the off-chain database has not been tampered with, the system supports data integrity verification at any time: S41: The verifier reads the hash digest Hdata and storage location identifier Locid of the target data from the blockchain. Since the hash digest is stored on the blockchain, it is immutable and can be used as a trusted verification benchmark. S42: Retrieve the encrypted data Cdata from the off-chain database based on the storage location identifier Locid; S43: Use the decryption key to decrypt the ciphertext data to obtain the current review data plaintext Dcurrent; S44: Calculate the SHA-256 hash digest Hcurrent of the plaintext data Dcurrent; S45: Compare Hcurrent with Hdata recorded on the blockchain. If the two are completely consistent, it means that the data has not been tampered with and the verification is successful. If there is a discrepancy, it indicates that the off-chain data has been modified, posing a security risk. S46: The verification results are recorded in the audit log, including verification time, verification results, verifier identity and other information.

[0023] Steps S5-S8: Data Destruction Steps To meet data protection regulations, the system supports controlled data destruction, such as... Figure 4 As shown: S51: Authorized users submit data deletion requests to smart contracts through the application interface layer. The deletion request includes the identifier of the target data and the reason for the request. S52: The smart contract verifies the requester's deletion permission, checks whether the requester is the data owner or has deletion authorization, and verifies whether the deletion request complies with the requirements of laws, regulations and system policies. S53: If the permission verification fails, the smart contract rejects the deletion request and logs it. If the verification passes, the data destruction process begins. S54: The smart contract queries the storage record of the data on the blockchain to obtain the storage location identifier Locid and related dependency information; S55: Analyze the dependencies of the data to be deleted, check whether there is derived data or calculation results generated based on the data, and ensure that the deletion operation will not affect the integrity of other legitimate data. S56: The smart contract calls the off-chain data destruction service, passing the storage location identifier Locid; S57: The data destruction service locates all relevant storage locations in the off-chain database based on the Locid location, including master data, backup data, and cached data; S58: Perform secure deletion operation for each storage location: Overwrite the storage area where the original data is located at least three times with random data to ensure that the data is unrecoverable, comply with data security destruction specifications, and prevent data recovery; Delete database index records and file system metadata, and clean up related database logs and temporary files; S59: Delete the encryption key Kdata corresponding to the data from the key management system. After the key is destroyed, even if there is any remaining encrypted data, it cannot be decrypted and restored. S60: Generate data destruction certificate, recording information such as destruction time, destruction scope, and operator; S61: Smart contracts record data destruction operations on the blockchain. Due to the immutability of the blockchain, historical records cannot be deleted, but the status identifier of the record can be updated. S62: The smart contract updates the data status from "valid" to "destroyed" and adds a destruction timestamp and operator information; S63: Although the hash digest Hdata still exists on the blockchain, since the corresponding original data and decryption key have been destroyed, the hash digest can no longer be associated with any valid information, thus achieving logical deletion of the data; S64: The smart contract returns a confirmation of destruction completion to the requester and provides proof of destruction as a compliance credential.

[0024] Example 2 This embodiment provides a blockchain-based system for protecting and preventing the tampering of review data, which is used in conjunction with the tampering prevention method in Embodiment 1. Figure 1 As shown, it includes the following layers: Application Interface Layer The application interface layer is the entry point for user interaction with the system, and includes the following components: Review Management Interface: Provides a web or mobile user interface for review experts to submit review data and for administrators to configure review processes and permission policies. The interface design follows the principle of ease of use and simplifies the operation process. Data query interface: Provides a RESTful API interface that supports authorized users to query review data, statistical results and historical records. The interface uses HTTPS protocol for encrypted transmission and JWT tokens for identity authentication. Statistical analysis interface: Provides data analysis and visualization functions, supports the generation of review reports, trend analysis charts, etc. Statistical calculations are completed by calling the trusted computing layer to ensure data privacy; Blockchain layer The blockchain layer is responsible for data storage, access control, and computation task scheduling, and includes the following modules: Smart contract module: An automated execution program deployed on the blockchain to achieve decentralized execution of business logic. The smart contract module includes: Permission verification unit: Verifies the user's access permissions and operation permissions, and determines the legitimacy of the request based on the access control policy; Task scheduling unit: generates and allocates computing tasks, and manages the lifecycle of tasks, including task creation, execution, completion, and exception handling; State Management Unit: Maintains the lifecycle state of data, records the entire process of data from creation, use to destruction, and supports state query and traceability. Consensus node module: Composed of multiple blockchain nodes, responsible for verifying the validity of transactions, reaching consensus through consensus algorithms, packaging transactions into blocks and adding them to the blockchain. The consensus mechanism can adopt algorithms such as PoW, PoS or PBFT, and the appropriate consensus scheme is selected according to the application scenario. Evidence storage module: Stores data evidence information in the distributed ledger of the blockchain. Each evidence storage record includes fields such as data hash digest, storage location identifier, access control policy, timestamp, submitter address and data status. Once the evidence storage record is on the chain, it cannot be tampered with, ensuring the trustworthiness of the data fingerprint. Trusted Computing Layer The trusted computing layer provides secure and privacy-preserving computing capabilities, including the following modules: Trusted Execution Environment (TEE) module: An isolated computing region implemented based on hardware security technology, which can adopt Intel SGX technology or ARM TrustZone technology. Intel SGX creates a secure enclave, dividing a protected memory region within the processor. Even if the operating system is attacked, the data within the enclave remains secure. ARM TrustZone, through hardware architecture separation, divides the system into a secure world and a normal world. Sensitive computations are performed in the secure world. The TEE application running in the Trusted Execution Environment is responsible for: Verify the legality and completeness of the computation task; Securely decrypt review data; Perform computational operations in an isolated environment; Encrypt the calculation results; Generate verifiable computational proofs; Oracle module: Acts as a bridge between the blockchain and the outside world, coordinating communication between on-chain smart contracts and off-chain trusted execution environments. The oracle's workflow includes: Listen for computation task events issued by smart contracts; Transmit task information to the TEE application; Receive calculation results and proofs from the TEE; Submitting the results back to the smart contract oracle adopts a decentralized architecture, and multiple oracle nodes can be deployed to improve reliability and resistance to attacks; Key Management Module: Responsible for the generation, storage, distribution and destruction of encryption keys. It uses a hardware security module (HSM) to protect the security of keys and prevent key leakage. The key management module implements strict access control. Only TEE applications can obtain keys after identity authentication and authorization. The mapping relationship between keys and data is stored in a secure database, and it supports key version management and rotation updates. Data storage layer The data storage layer is responsible for the persistent storage of encrypted data and includes the following components: Encrypted Database: Stores ciphertext of review data that has been symmetrically encrypted. The database adopts a distributed architecture, supports data sharding and redundant backup, and improves storage capacity and reliability. The database implements static encryption and transmission encryption, so even if the database is accessed illegally, attackers cannot obtain plaintext data. Keystore: A secure storage system specifically for storing encryption keys. The keystore is protected by hardware security modules and implements a multi-layered access control mechanism. Keys are stored in encrypted form and protected by a master key. The keystore records key usage logs and supports auditing and traceability. Access control module: Implements fine-grained data access control. Based on the access control policies defined by smart contracts, it controls access to off-chain databases and keystores. The access control module verifies the identity of the requester, checks the scope of permissions, and records access logs. It adopts an attribute-based access control ABAC model and supports flexible policy configuration. System Workflow The collaboration process between each layer is as follows: Data storage process: Users submit review data through the application interface layer → the data storage layer encrypts the data and stores it in an off-chain database → the blockchain layer records the data hash digest and access control policy → each layer returns a certificate of authenticity to the user. Data calculation process: The user initiates a computation request through the application interface layer → the blockchain layer verifies permissions and generates a computation task → the oracle passes the task to the trusted computing layer → the trusted execution environment obtains encrypted data from the data storage layer → decrypts and executes the computation in a secure environment → the encrypted result is returned to the blockchain layer → the blockchain layer stores the result and returns it to the user. Data validation process: The verifier reads the data hash digest from the blockchain layer → obtains the ciphertext data from the data storage layer → decrypts and calculates the hash value → compares it with the hash on the blockchain → returns the verification result; Data destruction process: User submits deletion request → Blockchain layer verifies deletion permission → Calls data storage layer's destruction service → Deletes off-chain encrypted data and key → Blockchain layer updates data status to destroyed → Returns destruction confirmation.

[0025] Example 3 This embodiment illustrates a specific application scenario: a scientific research project review system uses the technical solution of this invention to manage expert review data. System Configuration: Blockchain platform: Adopts a consortium blockchain architecture, with the organizer, regulatory agency and third-party auditing institution as consensus nodes; Trusted Execution Environment: Using servers configured with Intel SGX as compute nodes; Data storage: Deploy a distributed database cluster to provide high availability and disaster recovery capabilities. Application process: Phase 1: Review Data Submission. 50 experts submitted review data for 100 projects. Each piece of review data included fields such as project number, expert number, technical score, innovation score, and review comments, and was approximately 2KB in size. The system encrypted each piece of data using AES-256, which took approximately 0.5 milliseconds. The encrypted data was stored in an off-chain database. The SHA-256 hash digest of the data was calculated, which took approximately 0.1 milliseconds, and then submitted to the blockchain for notarization. In the exemplary test, the entire process took an average of approximately 1 second per piece of data (the main time was consumed in the blockchain transaction confirmation stage). Phase Two: Review and Statistical Calculation. After the review is completed, the average score for each project needs to be calculated. The system initiates calculation tasks for 100 projects, and each task needs to process 50 pieces of expert review data. The TEE application acquires the encrypted data in batches, decrypts it in a secure environment, and then performs score statistical calculation. In the exemplary test, the statistical calculation for a single project takes about 200 milliseconds, including the time for data acquisition, decryption, calculation, and encryption results. When multiple calculation tasks are processed concurrently in a trusted execution environment, the total calculation time for 100 projects is about 20 seconds. Compared with the calculation time of several hours required by traditional homomorphic encryption schemes, the calculation efficiency is improved by orders of magnitude. Phase 3: Data Integrity Verification. The regulatory agency conducts spot checks on some review data, randomly selecting review data from 10 projects. The hash digest is read from the blockchain, the encrypted data is obtained from the off-chain database, and after decryption, the hash value is recalculated and compared. The verification process of 10 data takes about 5 seconds. The verification results show that all data is intact and no tampering is found. Phase Four: One year after the data destruction review is completed, based on the data retention policy and deletion requests from some experts, it is necessary to destroy the relevant review data. After the system verifies the legality of the deletion request, the corresponding encrypted data in the off-chain database is deleted, the encryption key in the key management system is destroyed, and the data status is updated to destroyed on the blockchain. The destruction operation of a single piece of data takes about 2 seconds, with the main time consumed in the database operation and blockchain transaction confirmation process. Application effect: Privacy protection: Review data is stored in encrypted form, with only hash digests on the blockchain, effectively protecting the privacy of expert identities and review opinions; Tamper-proof: Blockchain notarization ensures that data fingerprints are immutable, and any modification to off-chain data can be detected; Computational performance: Compared with homomorphic encryption schemes, the computational efficiency is improved by more than 100 times, meeting the needs of real-time statistics; Compliance: Supports data destruction functionality and complies with data protection regulations.

[0026] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for preventing tampering of review data information based on blockchain technology, including a tamper-proof method, characterized in that: The anti-tampering method includes the following steps: S1. Data encryption and storage steps: Receive review data, generate a symmetric key to encrypt the review data, and store the encrypted ciphertext data in the off-chain database. S2. Data storage step: Calculate the hash digest of the review data, submit the hash digest, the storage location information of the encrypted data and the access control policy to the blockchain smart contract, and the smart contract records the storage information. S3, Trusted Computing Steps: When a computing request is received, the smart contract verifies whether the requester's identity complies with the access control policy. After successful verification, the smart contract generates a computing task event. The oracle listens for and captures the event, and then the computing task is passed to the trusted execution environment. The encrypted data is obtained and decrypted in the trusted execution environment. After performing the computing operation, the computing result is encrypted, and the encrypted computing result is returned to the smart contract. S4. Data verification step: Verify the integrity of the data in the off-chain database by reading the hash digest recorded on the blockchain.

2. The method for preventing tampering of review data information based on blockchain technology according to claim 1, characterized in that: The specific process of encrypting the review data in the data encryption and storage step includes: generating an AES encryption key and an initialization vector; The review data is divided into blocks, and data portions that are less than one block are padded. Each data block is then encrypted using AES-CBC mode to generate ciphertext data.

3. The method for preventing tampering of review data information based on blockchain technology according to claim 1, characterized in that: The access control policy includes authorized user identification, data access time window, and data usage purpose restrictions.

4. The method for preventing tampering of review data information based on blockchain technology according to claim 1, characterized in that: The trusted execution environment implements isolated computing regions based on hardware security technology. The computing operations are performed in isolated secure memory regions, and external systems cannot access the data in the secure memory regions.

5. The method for preventing tampering of review data information based on blockchain technology according to claim 1, characterized in that: The trusted computing step further includes the step of generating a computation proof, which includes a computation task identifier, a computation result hash value, an execution timestamp, and signature information of the trusted execution environment.

6. The method for preventing tampering of review data information based on blockchain technology according to claim 1, characterized in that: The anti-tampering method also includes a data destruction step: S5. Receive a data deletion request initiated by an authorized user verified by the smart contract, and verify deletion permission through the smart contract; S6. After verification, locate the encrypted data in the off-chain database based on the evidence storage record on the blockchain; S7. Delete the encrypted data and destroy the corresponding decryption key; S8. Record the data destruction operation on the blockchain and update the status of the evidence record to "destroyed".

7. The method for preventing tampering of review data information based on blockchain technology according to claim 1, characterized in that: In the data storage step, after the smart contract records the storage information, it also returns the blockchain hash value of the storage transaction to the submitter as a credential for subsequent querying and verification.

8. The method for preventing tampering of review data information based on blockchain technology according to claim 1, characterized in that: After detecting a computation task event issued by a smart contract, the oracle obtains the task information and passes it to the application in the trusted execution environment.

9. The method for protecting and preventing tampering of review data information based on blockchain technology according to claim 1, characterized in that: In the data verification step, the verifier determines the data integrity by comparing the hash value recalculated after decrypting the off-chain data with the hash digest recorded on the blockchain.

10. The method for preventing tampering of review data information based on blockchain technology according to claim 6, characterized in that: The anti-tampering method also includes the step of generating a data destruction certificate, which records the destruction time, destruction scope (including data storage location identifier and corresponding key identifier) ​​and operator information.

Images