Evaluation report data storage method and device based on block chain

Abstract

The invention provides an evaluation report data storage method and device based on a block chain. The method comprises the following steps: acquiring evaluation report data; performing hash calculation on the evaluation report data to obtain a target hash value; performing encryption processing on the evaluation report data to obtain encrypted data; obtaining a content identifier according to the encrypted data; obtaining target storage data according to the target hash value and the content identifier; and uploading the target storage data to a block chain for storage. The method comprises the following steps: acquiring evaluation report data, performing hash calculation and encryption processing on the evaluation report data to obtain a target hash value and encrypted data, then obtaining a content identifier according to the encrypted data, and then obtaining target storage data according to the target hash value and the content identifier. And the target storage data is uploaded to the block chain for storage, so that tampering of the assessment report data is prevented, and the security of assessment report data storage is improved.

Description

Technical Field

[0001] This invention relates to the field of data information processing technology, and also to a blockchain-based method and apparatus for storing evaluation reports. Background Technology

[0002] In traditional models, assessment reports (such as academic certificates and medical reports) are typically stored in centralized databases. This centralized storage architecture leads to a concentration of data security risks. Such systems rely on a single or a few centralized databases for data storage, resulting in highly centralized administrator privileges. This makes them vulnerable to internal abuse of power to tamper with data (such as modifying exam scores or forging test reports) or external attacks (such as database intrusion by hackers). Even with encryption or digital signature technologies, security can only be guaranteed during data transmission, not after data storage. For example, if an academic certificate or medical report is maliciously altered, users are unlikely to detect it, and relying on manual auditing or third-party verification afterward is extremely inefficient and costly. Secondly, data credibility and transparency are insufficient. Traditional systems lack publicly available and tamper-proof operation records; traces of data generation, modification, or access can be deleted or forged, making it difficult to trace responsibility. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a blockchain-based method and apparatus for storing evaluation report data, so as to improve the security of evaluation report data storage.

[0004] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: A first aspect of the present invention provides a blockchain-based method for storing evaluation report data, comprising: Obtain assessment report data; The target hash value is obtained by performing a hash calculation on the evaluation report data; The evaluation report data is encrypted to obtain encrypted data; Based on the encrypted data, a content identifier is obtained; The target storage data is obtained based on the hash value and the content identifier; The target storage data is uploaded to the blockchain for storage.

[0005] Optionally, the evaluation report data is hashed to obtain a target hash value, including: The evaluation report data is converted into bytes to obtain a byte sequence; The byte sequence is padded with data to obtain padded data; The filling data is divided into blocks to obtain block data; The target hash value is obtained based on the segmented data and the initial hash value.

[0006] Optionally, the evaluation report data is encrypted to obtain encrypted data, including: Obtain an encryption key and a random value of a preset length; The evaluation report data is preprocessed to obtain preprocessed data; The preprocessed data is encrypted using the encryption key and the random value to obtain encrypted data.

[0007] Optionally, based on the encrypted data, a content identifier is obtained, including: The encrypted data is divided into multiple data blocks; Based on the multiple data blocks, a directed acyclic graph is determined; The content identifier is determined based on the hash value of the root node of the directed acyclic graph.

[0008] Optionally, the content identifier is determined based on the hash value of the root node of the directed acyclic graph, including: Based on the directed acyclic graph, the hash value of the root node is calculated; The content identifier is obtained based on the hash value of the root node.

[0009] Optionally, the target stored data is obtained based on the target hash value and the content identifier, including: Obtain the preset public key, timestamp, and preset data format; According to the preset data format, the target hash value, the content identifier, the preset public key, and the timestamp are encapsulated to obtain the target storage data.

[0010] Optionally, the method further includes: Obtain verified user data and pre-deployed smart contracts; The validity of the target stored data is verified based on the verified user data and the pre-deployed smart contract, and the verification result is obtained.

[0011] A second aspect of the present invention provides a blockchain-based evaluation report data storage device, comprising: The acquisition module is used to acquire assessment report data; The processing module is used to perform hash calculation on the evaluation report data to obtain a target hash value; encrypt the evaluation report data to obtain encrypted data; obtain a content identifier based on the encrypted data; obtain target storage data based on the target hash value and the content identifier; and upload the target storage data to the blockchain for storage.

[0012] A third aspect of the present invention provides a computing device, comprising: a processor and a memory storing a computer program, wherein the computer program, when executed by the processor, performs the method described in the first aspect.

[0013] A fourth aspect of the present invention provides a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform the method as described in the first aspect.

[0014] The above-described solution of the present invention has at least the following beneficial effects: The above-described solution of the present invention obtains evaluation report data, performs hash calculation and encryption on the evaluation report data to obtain target hash value and encrypted data, then obtains content identifier based on encrypted data, and obtains target storage data based on hash value and the content identifier, and uploads the target storage data to the blockchain for storage, thereby preventing tampering with the evaluation report data and improving the security of evaluation report data storage. Attached Figure Description

[0015] Figure 1 This is a flowchart illustrating the blockchain-based evaluation report data storage method in an embodiment of the present invention. Figure 2 This is a flowchart illustrating a blockchain-based evaluation report data storage method in a specific embodiment of the present invention. Figure 3 This is a schematic diagram of the process for verifying target stored data in a specific embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of a blockchain-based evaluation report data storage device in an embodiment of the present invention. Detailed Implementation

[0016] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0017] like Figure 1 As shown, an embodiment of the present invention proposes a blockchain-based method for storing evaluation reports, including the following steps: Step 101: Obtain the evaluation report data; Step 102: Perform hash calculation on the evaluation report data to obtain the target hash value; Step 103: Encrypt the evaluation report data to obtain encrypted data; Step 104: Obtain the content identifier based on the encrypted data; Step 105: Obtain the target storage data based on the hash value and the content identifier; Step 106: Upload the target storage data to the blockchain for storage.

[0018] The blockchain-based evaluation report data storage method of this invention obtains evaluation report data, performs hash calculation and encryption on the evaluation report data to obtain a target hash value and encrypted data, then obtains a content identifier based on the encrypted data, and obtains target storage data based on the target hash value and the content identifier, and uploads the target storage data to the blockchain for storage, thereby preventing tampering with the evaluation report data and improving the security of evaluation report data storage.

[0019] In an optional embodiment of the present invention, the assessment report data obtained in step 101 may be data such as academic certificates or medical reports, and the assessment report data to be stored may be stored according to the user's needs.

[0020] In an optional embodiment of the present invention, step 102 includes: Step 1021: Perform byte conversion on the evaluation report data to obtain a byte sequence; Specifically, when the evaluation report data is text data, it is converted into a byte sequence using a preset encoding format; when the evaluation report data is binary data, it is directly read as a byte sequence.

[0021] Step 1022: Fill the byte sequence with data to obtain filled data; Specifically, data padding involves filling the byte sequence with padding data that is a multiple of 512 bits minus 64 bits. This padding is achieved by appending binary 1s or 0s to the end of the byte sequence. The length of the padding data is... The actual number of zeros padded is 448 − (original length + 1) mod 512 (if the result is negative, add 512).

[0022] Step 1023: The filling data is divided into blocks to obtain block data; Specifically, the padding data is divided into 16 blocks of 32-bit words to obtain block data.

[0023] Step 1024: Obtain the target hash value based on the block data and the initial hash value.

[0024] Specifically, the initial hash value is eight 32-bit initial constants, which are the first 32 bits of the fractional part of the square root of the first eight prime numbers of natural numbers, serving as the initial state of the compression function. Each block of data is expanded to 64 words. After 64 iterations, the initial hash value is updated to obtain the updated hash value. The eight updated hash values ​​are concatenated in big-endian order to form 256 bits (32 bytes) of binary data, which is then converted into a hexadecimal string, i.e., the target hash value.

[0025] In an optional embodiment of the present invention, step 103 includes: Step 1031: Obtain an encryption key and a random value of a preset length; Specifically, a cryptographically secure random number generator can be used to generate random values ​​and a preset-length encryption key to prevent the same plaintext from generating the same ciphertext. Here, the preset-length encryption key can be a 256-bit key.

[0026] Step 1032: Preprocess the evaluation report data to obtain preprocessed data; Specifically, the evaluation report data can be populated and segmented, and the segmented data obtained after segmentation is the preprocessed data.

[0027] Step 1033: Encrypt the preprocessed data according to the encryption key and the random value to obtain encrypted data.

[0028] Specifically, through The preprocessed data is encrypted using T=MAC(K,IV,P) to obtain encrypted data, where C is the encrypted data. Here, K is the encryption function, P is the encryption key, and CTR is the preprocessed data. For XOR operation, T is the authentication tag, MAC(K,IV,P) is the message authentication code, used to verify the integrity and authenticity of the data and ensure that the ciphertext has not been tampered with, and IV is a random value.

[0029] In an optional embodiment of the present invention, step 104 includes: Step 1041: Divide the encrypted data into multiple data blocks; Specifically, encrypted data can be divided into multiple data blocks of a fixed size (such as 256KB).

[0030] Step 1042: Determine a directed acyclic graph based on the multiple data blocks; Specifically, each data block is treated as a node, containing: block content (encrypted data) and a unique identifier (such as the block's hash value); if block A references block B (such as block dependency or merging), a directed edge is established from A to B, and the absence of cycles is ensured through topological sorting or hash pointers; each node contains child node hashes, forming a verifiable tree structure, i.e., a directed acyclic graph.

[0031] Step 1043: Determine the content identifier based on the hash value of the root node of the directed acyclic graph.

[0032] In practice, the encrypted data can be divided into blocks (default 256KB) using the local InterPlanetary File System, the hash of each block can be calculated, and then a directed acyclic graph can be constructed. The hash value of the root node of the directed acyclic graph is the content identifier.

[0033] In an optional embodiment of the present invention, step 1043 includes: Step 10431: Calculate the hash value of the root node based on the directed acyclic graph. Step 10432: Obtain the content identifier based on the hash value of the root node.

[0034] Specifically, starting from the leaf nodes, the hash value of each node is calculated from the bottom up. Node hash = hash(node ​​content + list of child node hashes). Root node determination: The final top-level node hash is the root hash of the directed acyclic graph, representing a unique identifier for the entire data structure, i.e., the content identifier.

[0035] In one optional embodiment, the step of generating a content identifier includes: Use user private key To ensure the accuracy of encrypted data F, an encrypted signature is performed on the encrypted data F, namely: ; Can be considered encrypted data identifier, It is a unique identifier for the encrypted data F.

[0036] Then, the data is split into blocks to encrypt the data. Divide into One data block, namely: ; For the segmented first One file data block Using the private key The algorithm encrypts each data block, generating encrypted file blocks. ,Right now: ; Then, use the tag generation function. Calculate the tags of encrypted file blocks ,Right now: ; The encrypted data file generated above Construct a Merkle hash tree for the entire file and calculate the root node value of that Merkle hash tree. ,Right now: ; Use a hash function to calculate the signature of the root node. ,Right now: ; Sign the root node As a content identifier.

[0037] In an optional embodiment of the present invention, step 105 includes: Step 1051: Obtain the preset public key, timestamp, and preset data format; Specifically, the default public key is the user's public key, the timestamp is the time when the hash value was generated, and the default data format is JSON (a lightweight data exchange format).

[0038] Step 1052: According to the preset data format, the hash value, the content identifier, the preset public key, and the timestamp are encapsulated to obtain the target storage data.

[0039] Specifically, the identifier metadata for each encrypted data block is calculated, namely: ;in, This represents the identifier metadata for the i-th encrypted data block, where i is the number of the encrypted data block. For string concatenation operators, A unique identifier for encrypted data F.

[0040] Using the homomorphic signature of each data block mentioned above, calculate the homomorphic signature of the entire encrypted file, i.e.: ;in, For the homomorphic signature of the entire encrypted file, For cryptographic hash functions, For the identifier metadata of the i-th encrypted data block, is a global parameter, and sk is the user's private key.

[0041] Will The preset public key, timestamp, and other metadata are encapsulated into structured data in JSON format and used as the target storage data.

[0042] In an optional embodiment of the present invention, the method further includes: Step 107: Obtain verified user data and pre-deployed smart contracts; Specifically, the verification user data is the content identifier and publicly accessible on-chain hash value of the report to be verified (i.e., the evaluation report data) provided by the verification party. The pre-deployed smart contract executes the following logic: records the evaluation report data status as "certified", binds the timestamp to the block header, and sets verification rules (only authorized institutions can decrypt the original evaluation report data).

[0043] Step 108: Verify the validity of the target stored data based on the verified user data and the pre-deployed smart contract to obtain the verification result.

[0044] Specifically, an arithmetic circuit is constructed using the ZoKrates framework (an Ethereum-based zero-knowledge proof application development framework) to define the verification logic (the hash value of the original file equals the on-chain record). Then, without exposing the original file content, a concise proof is generated using zk-SNARKs (a zero-knowledge proof protocol). A dedicated zero-knowledge proof verification smart contract is deployed, with built-in elliptic curve pairing parameters (BN254 curve) and a verification key. The verifier submits the proof to the pre-deployed smart contract, which calls a pre-compiled verification function, returns a "valid" or "invalid" result, and records it on the blockchain. An access policy is then defined through the smart contract (only authorized institutions can decrypt and view the report). In one optional embodiment, the pre-deployed smart contract receives the zero-knowledge proof generated by the verification user, verifies the proof using the built-in elliptic curve pairing parameters and the verification key, and returns a "valid" or "invalid" result.

[0045] like Figure 2 and Figure 3 As shown, a specific embodiment of the blockchain-based evaluation report data storage method of the present invention includes: Step 111: Obtain the evaluation report data; Acquire academic certificates, medical reports, and other data that need to be stored on the blockchain, and store them as assessment report data through subsequent processing.

[0046] Step 112: Perform hash calculation on the evaluation report data to obtain the target hash value; Choose a hash function with strong collision resistance (such as SHA-256) to perform hash calculation on the evaluation report content (i.e. evaluation report data) and generate a unique hash value of fixed length.

[0047] Step 113: Encrypt the evaluation report data to obtain encrypted data; pass The evaluation report data is encrypted using T=MAC(K,IV,P) to obtain encrypted data.

[0048] Step 114: Obtain the content identifier based on the encrypted data; The original report file (i.e., the evaluation report data) is encrypted using a symmetric encryption algorithm (such as AES-256) and then uploaded to the IPFS (InterPlanetary File System, a content-addressable peer-to-peer hypermedia distribution protocol) network. IPFS generates a unique content identifier based on content addressing, ensuring that the file is immutable and globally accessible.

[0049] Step 115: Obtain the target storage data based on the hash value and content identifier; The obtained target hash value, content identifier, generation time, generator public key and other metadata are encapsulated into structured data in JSON format and used as target storage data.

[0050] Step 116: Upload the target storage data to the blockchain for storage.

[0051] The target data is uploaded to the public blockchain (Ethereum sidechain). The metadata is used as the transaction payload and broadcast to the network via blockchain nodes. The transaction includes a digital signature (signed using the generator's private key) to ensure the data source is trustworthy. After successful upload, a pre-deployed smart contract is automatically invoked to execute the following logic: record the report status as "proof-provided", bind a timestamp to the block header, and set verification rules (only authorized institutions can decrypt the original file).

[0052] Step 117: Obtain verified user data and pre-deployed smart contracts; Specifically, the verification user data consists of the content identifier and publicly accessible on-chain hash value of the report to be verified (i.e., the evaluation report data) provided by the verifier. The pre-deployed smart contract executes the following logic: records the evaluation report data status as "certified", binds a timestamp to the block header, and sets verification rules (only authorized institutions can decrypt the original evaluation report data). In one optional embodiment, the verifier (i.e., the verification user) provides the content identifier and publicly accessible on-chain hash value of the report to be verified, constructs an arithmetic circuit using an Ethereum-based zero-knowledge proof application development framework, defines the verification logic (the original file hash value equals the on-chain record), and then generates a concise proof through a zero-knowledge proof protocol without exposing the original file content.

[0053] Step 118: Verify the validity of the target stored data and obtain the verification result.

[0054] A dedicated zero-knowledge proof verification smart contract is deployed, with built-in elliptic curve pairing parameters (BN254 curve) and verification keys. The verifier submits the proof to the contract, which calls a pre-compiled verification function, returns a "valid" or "invalid" result, and records it on the blockchain. Then, an access policy is defined through the smart contract (only authorized institutions can decrypt and view the report).

[0055] The on-chain verification of the evaluation report and privacy protection verification are closely linked through a multi-layered collaborative mechanism in the overall technical implementation, constructing a closed-loop trusted verification system. First, the on-chain data process provides an immutable trust anchor for privacy verification: after the evaluation report is processed by the collision-resistant hash algorithm (SHA-256), a unique hash value is generated. Simultaneously, the original file is encrypted and stored on the IPFS network to generate a content identifier. These two elements, along with metadata such as timestamps and the generator's public key, are encapsulated and written into the blockchain. This process not only ensures the trustworthiness of the data source through the distributed ledger but also locks in a comparison benchmark for subsequent verification. The core logic of privacy protection verification is to use zero-knowledge proof technology to prove that the hash value of the user-submitted file is completely consistent with the on-chain record without exposing the original content. This verification process directly relies on the hash value permanently stored on the blockchain, forming a trust transfer chain of "data storage - privacy verification".

[0056] This invention discloses a blockchain-based evaluation report data storage method. The method anchors data hash values ​​to the blockchain, encrypts the original files in IPFS, and separates storage and verification by binding content identifiers to on-chain hash values. Distributed storage reduces on-chain load, and the strong correlation between content identifiers and hashes forms a dual anti-tampering mechanism. During the verification phase, zk-SNARKs are used to generate proofs, verifying hash consistency without disclosing the original data content. This method overcomes the limitation of traditional encrypted verification requiring data exposure, achieving "data usable but not visible," making it suitable for privacy-sensitive scenarios. It improves the security and efficiency of evaluation report data storage and effectively protects data privacy.

[0057] like Figure 4 As shown, an embodiment of the present invention proposes a blockchain-based evaluation report data storage device 200, comprising: Module 201 is used to acquire evaluation report data; The processing module 202 is used to perform hash calculation on the evaluation report data to obtain a target hash value; encrypt the evaluation report data to obtain encrypted data; obtain a content identifier based on the encrypted data; obtain target storage data based on the target hash value and the content identifier; and upload the target storage data to the blockchain for storage.

[0058] Optionally, the evaluation report data is hashed to obtain a target hash value, including: The evaluation report data is converted into bytes to obtain a byte sequence; The byte sequence is padded with data to obtain padded data; The filling data is divided into blocks to obtain block data; The target hash value is obtained based on the segmented data and the initial hash value.

[0059] Optionally, the evaluation report data is encrypted to obtain encrypted data, including: Obtain an encryption key and a random value of a preset length; The evaluation report data is preprocessed to obtain preprocessed data; The preprocessed data is encrypted using the encryption key and the random value to obtain encrypted data.

[0060] Optionally, based on the encrypted data, a content identifier is obtained, including: The encrypted data is divided into multiple data blocks; Based on the multiple data blocks, a directed acyclic graph is determined; The content identifier is determined based on the hash value of the root node of the directed acyclic graph.

[0061] Optionally, the content identifier is determined based on the hash value of the root node of the directed acyclic graph, including: Based on the directed acyclic graph, the hash value of the root node is calculated; The content identifier is obtained based on the hash value of the root node.

[0062] Optionally, the target stored data is obtained based on the target hash value and the content identifier, including: Obtain the preset public key, timestamp, and preset data format; According to the preset data format, the target hash value, the content identifier, the preset public key, and the timestamp are encapsulated to obtain the target storage data.

[0063] Optionally, the processing module 202 is further configured to: Obtain verified user data and pre-deployed smart contracts; The validity of the target stored data is verified based on the verified user data and the pre-deployed smart contract, and the verification result is obtained.

[0064] The blockchain-based evaluation report data storage device of this invention acquires evaluation report data, performs hash calculation and encryption on the evaluation report data to obtain a target hash value and encrypted data, then obtains a content identifier based on the encrypted data, and obtains target storage data based on the target hash value and the content identifier, and uploads the target storage data to the blockchain for storage, thereby preventing tampering with the evaluation report data and improving the security of evaluation report data storage.

[0065] It should be noted that this device corresponds to the method described above, and all implementations in the method embodiments described above are applicable to the embodiments of this device and can achieve the same technical effect. Further details will not be provided in this embodiment.

[0066] This invention also provides a computing device, including: a processor and a memory storing a computer program, wherein the computer program, when executed by the processor, performs the method as described in any of the above embodiments. All implementations in the above method embodiments are applicable to the embodiments of this device and can achieve the same technical effects. Further details are omitted in this embodiment.

[0067] This invention also provides a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform the method as described in any of the above embodiments. All implementations in the above method embodiments are applicable to the embodiments of this device and can achieve the same technical effects. Further details are omitted in this embodiment.

[0068] It should be noted that in the apparatus and method of the present invention, the components or steps can obviously be decomposed and / or recombined. These decompositions and / or recombinations should be considered equivalent solutions of the present invention. Furthermore, the steps for performing the above series of processes can naturally be performed in the order described and in chronological order, but are not necessarily required to be performed in chronological order. Some steps can be performed in parallel, overlapping, or independently of each other.

[0069] It should be noted that in the above embodiments, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments described above is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0070] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A blockchain-based method for storing evaluation report data, characterized in that, include: Obtain assessment report data; The target hash value is obtained by performing a hash calculation on the evaluation report data; The evaluation report data is encrypted to obtain encrypted data; Based on the encrypted data, a content identifier is obtained; The target storage data is obtained based on the hash value and the content identifier; The target storage data is uploaded to the blockchain for storage.

2. The blockchain-based evaluation report data storage method according to claim 1, characterized in that, The evaluation report data is hashed to obtain the target hash value, including: The evaluation report data is converted into bytes to obtain a byte sequence; The byte sequence is padded with data to obtain padded data; The filling data is divided into blocks to obtain block data; The target hash value is obtained based on the segmented data and the initial hash value.

3. The blockchain-based evaluation report data storage method according to claim 1, characterized in that, The evaluation report data is encrypted to obtain encrypted data, including: Obtain an encryption key and a random value of a preset length; The evaluation report data is preprocessed to obtain preprocessed data; The preprocessed data is encrypted using the encryption key and the random value to obtain encrypted data.

4. The blockchain-based evaluation report data storage method according to claim 1, characterized in that, Based on the encrypted data, a content identifier is obtained, including: The encrypted data is divided into multiple data blocks; Based on the multiple data blocks, a directed acyclic graph is determined; The content identifier is determined based on the hash value of the root node of the directed acyclic graph.

5. The blockchain-based evaluation report data storage method according to claim 4, characterized in that, Based on the hash value of the root node of the directed acyclic graph, the content identifier is determined, including: Based on the directed acyclic graph, the hash value of the root node is calculated; The content identifier is obtained based on the hash value of the root node.

6. The blockchain-based evaluation report data storage method according to claim 1, characterized in that, Based on the target hash value and the content identifier, the target stored data is obtained, including: Obtain the preset public key, timestamp, and preset data format; According to the preset data format, the target hash value, the content identifier, the preset public key, and the timestamp are encapsulated to obtain the target storage data.

7. The blockchain-based evaluation report data storage method according to claim 1, characterized in that, Also includes: Obtain verified user data and pre-deployed smart contracts; The validity of the target stored data is verified based on the verified user data and the pre-deployed smart contract, and the verification result is obtained.

8. A blockchain-based evaluation report data storage device, characterized in that, include: The acquisition module is used to acquire assessment report data; The processing module is used to perform hash calculation on the evaluation report data to obtain the target hash value; The evaluation report data is encrypted to obtain encrypted data; a content identifier is obtained based on the encrypted data; and target storage data is obtained based on the target hash value and the content identifier. The target storage data is uploaded to the blockchain for storage.

9. A computing device, characterized in that, include: A processor, a memory storing a computer program, wherein the computer program, when executed by the processor, performs the method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The system stores instructions that, when executed on a computer, cause the computer to perform the method as described in any one of claims 1 to 7.

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