A government affair data dynamic authorization management method based on secure multi-party computation

Abstract

The application discloses a kind of based on government affair data dynamic authorization management method of secure multi-party computation, it is related to government affair data security authorization management field, including, to each participant is assigned unique identity mark, asymmetric key pair is generated using national secret SM2 algorithm, public key and institutional attribute information are registered to alliance chain smart contract, generate identity credential package;Participating party is based on attribute information in identity credential package, through secure multi-party computation protocol collaborative generation quantum-resistant dynamic attribute-based encryption key fragment, using threshold secret sharing technology is distributed to each participant.The application realizes threshold decryption and token verification by alliance chain verification smart contract, generates authorization record, according to the access control policy of edge computing node configured by authorization record, and using the response data query of inadvertent transmission protocol, access log is monitored by audit node, dynamically adjusts attribute weight parameter and is synchronized to key fragment.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of government data security authorization management, and particularly relates to a government data dynamic authorization management method based on secure multi-party computation. BACKGROUND

[0002] In the field of government data security authorization management, attribute-based encryption access control technology has been widely used. By matching the attribute information of data users with access strategies, fine-grained access control is achieved. The core is to use smart contracts to automatically execute predefined authorization strategies, and to record authorization operations through a distributed ledger to ensure audit tracking. Such solutions have achieved certain results in static strategy execution and operation transparency, and can meet the basic security needs of regular government data sharing scenarios. With the surge in the amount of business carried by government cloud platforms and the increase in data sensitivity, especially in dynamic scenarios such as emergency management and cross-regional collaboration, the traditional technical architecture gradually shows the problem of inadequate adaptability.

[0003] Although the existing solutions have been optimized in terms of strategy execution efficiency and audit tracking, their core authorization mechanism still relies on predefined static strategy models, which makes it difficult to cope with the frequent changes in access requirements and security situation in the government environment. Existing technologies usually use fixed attribute encryption key generation methods, which lack the ability to perceive and respond to dynamic environmental factors. In the process of handling public emergencies, government data of different security levels needs to be dynamically adjusted according to real-time risk indicators. However, the traditional ABE scheme cannot automatically adapt the key parameters. Government data sharing involves multiple mutually untrusted functional departments. Most existing solutions rely on trusted third parties for key management, which poses a single point of failure and privacy leakage risk. SUMMARY

[0004] In view of the above existing problems, the present application is proposed.

[0005] Therefore, the present application provides a government data dynamic authorization management method based on secure multi-party computation, which solves the problem of insufficient real-time dynamic adaptability caused by static strategies and centralized dependence in the government data authorization process.

[0006] To solve the above technical problems, the present application provides the following technical solutions:

[0007] In the first aspect, the present application provides a government data dynamic authorization management method based on secure multi-party computation, which includes assigning a unique identity to each participant, generating an asymmetric key pair using the SM2 algorithm, registering the public key and institutional attribute information to the alliance chain smart contract, and generating an identity credential package.

[0008] Based on the attribute information in the identity credential package, the participants collaboratively generate quantum-resistant dynamic attribute-based encryption key fragments through a secure multi-party computation protocol, and distribute them to each participant using threshold secret sharing technology.

[0009] An FPGA acceleration card is used to receive quantum-resistant dynamic property base encryption key fragments, and a multi-party secure computation protocol is executed within a hardware secure enclave to obtain decision results and ciphertext fragments of authorization tokens.

[0010] The decision result and encrypted fragment of the permission token are received through the verification smart contract on the consortium blockchain. The complete permission token is recovered by decryption through the threshold and its validity is verified to generate an authorization record.

[0011] Configure access control policies for edge computing nodes based on authorization records, and respond to encrypted queries from data requesters using an unobtrusive transport protocol;

[0012] The audit node monitors the access logs of the data requester, dynamically adjusts the attribute weight parameters through a secure multi-party computation protocol, and synchronizes them to the quantum-resistant dynamic attribute base encryption key fragment.

[0013] As a preferred embodiment of the dynamic authorization management method for government data based on secure multi-party computation described in this invention, the method includes: assigning unique identity identifiers to each participant, generating asymmetric key pairs using the national cryptographic SM2 algorithm, registering the public key and institutional attribute information to the consortium blockchain smart contract, and generating an identity credential package, comprising the following steps.

[0014] The government data management unit uses a hash algorithm to generate a unique identity for each participant and uses the national cryptographic SM2 algorithm to generate an asymmetric key pair on an elliptic curve to obtain a private key and a public key.

[0015] Write the private key into the hardware security module, configure a two-factor access control policy, obtain a physically protected private key storage handle, and construct a standardized organizational attribute JSON object based on the administrative responsibilities of the participating parties.

[0016] The unique identifier, public key, and standardized institutional attribute JSON object are combined into a registration transaction data structure;

[0017] Based on the registered transaction data structure, the registration contract deployed on the consortium blockchain obtains the call results of block height and transaction hash. The CA institution verifies the call results of block height and transaction hash, and the root certificate pair is used to perform SM2 signing to obtain a digital certificate.

[0018] Integrate unique identifiers, public keys, standardized organization attribute JSON objects, and digital certificates to generate an identity credential package.

[0019] As a preferred embodiment of the dynamic authorization management method for government data based on secure multi-party computation described in this invention, the participating parties collaboratively generate quantum-resistant dynamic attribute-based encryption key fragments based on attribute information in the identity credential package through a secure multi-party computation protocol, including the following steps.

[0020] The government data management unit parses the institutional attribute information in the identity credential package and converts it into a standardized binary attribute vector. Based on the standardized binary attribute vector, all participating parties collaboratively generate a cryptographic public matrix and an attribute association matrix through a secure multi-party protocol.

[0021] The real-time weight value is obtained based on the current timestamp and the initial weight;

[0022] Using the attribute association matrix and real-time weight values, the master key is securely computed via MPC to generate quantum-resistant dynamic attribute base encryption key fragments.

[0023] As a preferred embodiment of the dynamic authorization management method for government data based on secure multi-party computation described in this invention, the method involves distributing data to each participating party using threshold-based secret sharing technology, including the following steps.

[0024] To counteract quantum dynamic property basis encryption key fragmentation, discrete Gaussian noise is added to the fragments to obtain a noisy key;

[0025] A polynomial is constructed based on the noisy key, and the polynomial coefficient vector is obtained.

[0026] The key fragments for each participant are obtained using the Shamir threshold secret sharing method, and the key fragments are encrypted using an additive homomorphic encryption scheme to obtain an encrypted fragment set.

[0027] Each participant decrypts and verifies the encrypted fragment set, and writes the verified key fragment into the hardware security module.

[0028] As a preferred embodiment of the dynamic authorization management method for government data based on secure multi-party computation described in this invention, the method includes the following steps: using an FPGA acceleration card to receive quantum-resistant dynamic attribute-based encryption key fragments, executing a secure multi-party computation protocol within a hardware-secure enclave, and obtaining decision results and ciphertext fragments of authorization tokens.

[0029] The TrustZone secure enclave firmware, which is physically isolated, is loaded onto the FPGA to generate a unique chip key. The received encrypted fragment set is then processed using Paillier homomorphic decryption to obtain the plaintext key fragment.

[0030] The noisy key is reconstructed by Lagrange interpolation over a finite field to obtain a verified set of shards. The FPGA's built-in true random number generator generates a triple pool in parallel.

[0031] The encrypted matching result of the request attribute and dynamic weight is calculated based on the GMW protocol. The encrypted matching result is decrypted using the Shamir algorithm to obtain the decision result and the ciphertext fragment of the permission token.

[0032] As a preferred embodiment of the dynamic authorization management method for government data based on secure multi-party computation described in this invention, the method includes the following steps: receiving decision results and encrypted fragments of authorization tokens through a verification smart contract on a consortium blockchain, recovering the complete authorization token through threshold decryption and verifying its validity, and generating an authorization record.

[0033] By verifying the smart contract, listening to the blockchain event log, obtaining the encrypted decision results and the transaction request of the token fragment, the raw data packet to be processed is obtained. The digital signature of the transaction request of the token fragment is verified using the public key, and the data packet with the signature verified is obtained.

[0034] The smart contract collects encrypted permission token fragments from participating nodes to obtain a set of fragments that meet the threshold requirements. It then reconstructs the noisy key using the Shamir secret sharing algorithm, decrypts it to obtain the plaintext permission token, and verifies the plaintext permission token using a multi-dimensional joint verification method to obtain the verified plaintext permission token content.

[0035] Generate an authorization record based on the verified token content.

[0036] As a preferred embodiment of the dynamic authorization management method for government data based on secure multi-party computation described in this invention, the method includes the following steps: configuring access control policies for edge computing nodes according to authorization records, and responding to encrypted queries from data requesters using an unobtrusive transmission protocol.

[0037] Edge nodes obtain authorization records from the blockchain, extract the list of allowed operations, the list of prohibited operations, and the effective conditions from the permission declaration fields, and obtain a structured policy object;

[0038] The structured policy object is converted into a policy language file of the Linux security enhancement module, generating a binary policy file with type enforcement rules and access vectors, resulting in a policy module. The secure loading interface loads the policy module into the Linux security module, obtaining the policy activation status code. The voice key is used to symmetrically decrypt the encrypted query data submitted by the requester, resulting in a plaintext query statement. The operation fields in the query statement are compared with the list of allowed operations in the policy object to obtain a securely filtered query syntax tree. The target data index value is extracted from the securely filtered query syntax tree.

[0039] The requester calculates the blinded request parameters based on the target data index value, combined with the elliptic curve generator and random number, using the elliptic curve blinding algorithm, and obtains the unintentional transport protocol request packet.

[0040] Edge nodes use their own private keys to hash and obfuscate all data items, generating a corresponding set of response data. The requester uses pre-shared elliptic curve parameters and its own selected bit information to extract and decrypt the target data item from the response packet, obtaining the plaintext query result.

[0041] As a preferred embodiment of the dynamic authorization management method for government data based on secure multi-party computation described in this invention, the method includes the following steps: The audit node monitors the access logs of the data requester, dynamically adjusts the attribute weight parameters through a secure multi-party computation protocol, and synchronizes them to a quantum-resistant dynamic attribute base encryption key fragment.

[0042] The audit node receives the encrypted access log stream from the edge computing node via the TLS 1.3 protocol, obtains the encrypted log block with timestamp, compares the Merkle root hash of the encrypted log block with the blockchain evidence, and outputs the standardized log data that has passed the verification.

[0043] Each audit node aggregates log feature values ​​through a secure multi-party protocol to obtain encrypted statistical results;

[0044] Based on the statistical results, abnormal access behaviors exceeding the 3σ range are identified, and risk event reports are obtained. Based on the risk reports, the weight adjustment gradient is derived through the MPC protocol.

[0045] The attribute association matrix is ​​dynamically adjusted using weighted gradient adjustment to obtain the adjusted matrix parameter set. Based on the adjusted matrix parameter set, a new key shard is generated through threshold secret sharing. The Merkle root hash of the new key shard is written into the smart contract to obtain the policy update transaction receipt.

[0046] In a second aspect, the present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, wherein: when the computer program is executed by the processor, it implements any step of the dynamic authorization management method for government data based on secure multi-party computation as described in the first aspect of the present invention.

[0047] Thirdly, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program is executed by a processor, it implements any step of the dynamic authorization management method for government data based on secure multi-party computation as described in the first aspect of the present invention.

[0048] The beneficial effects of this invention are as follows: Each participating party is assigned a unique identity identifier, and an asymmetric key pair is generated using the national cryptographic SM2 algorithm. The public key and institutional attribute information are registered to the consortium blockchain smart contract to generate an identity credential package. Based on the attribute information in the identity credential package, a quantum-resistant dynamic attribute-based encrypted key fragment is collaboratively generated through a secure multi-party computation protocol and distributed using threshold secret sharing technology. An FPGA acceleration card is used to execute the multi-party secure computation protocol within a hardware secure enclave to obtain the decision result and the encrypted fragment of the permission token. Threshold decryption and token verification are implemented through the consortium blockchain verification smart contract, generating authorization records. Access control policies for edge computing nodes are configured based on these authorization records, and an unintentional transmission protocol is used to respond to data queries. Access logs are monitored through audit nodes, and attribute weight parameters are dynamically adjusted and synchronized to the key fragment. Attached Figure Description

[0049] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0050] Fig. 1 This is a flowchart of a dynamic authorization management method for government data based on secure multi-party computation.

[0051] Fig. 2 Flowchart for generating identity credential packages for government data participants.

[0052] Fig. 3 A flowchart for collaborative generation of quantum dynamic property base encryption key fragments.

[0053] Fig. 4 This is a flowchart of the dynamic authorization verification process based on hardware security enclaves. Detailed Implementation

[0054] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0055] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0056] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0057] Reference Figs. 1-4 This is one embodiment of the present invention, which provides a dynamic authorization management method for government data based on secure multi-party computation, including the following steps:

[0058] S1. Assign a unique identity identifier to each participant, generate an asymmetric key pair using the national cryptographic SM2 algorithm, register the public key and institutional attribute information to the consortium blockchain smart contract, and generate an identity credential package.

[0059] S1.1 The government data management unit uses a hash algorithm to generate a unique identity for each participant and uses the national cryptographic SM2 algorithm to generate an asymmetric key pair on an elliptic curve to obtain a private key and a public key.

[0060] Specifically, the expression is,

[0061] ID = SM3(O||D||N);

[0062] Where ID is a unique identifier, O is the organization code, D is the administrative division code, and N is a random number.

[0063] S1.2 Write the private key into the hardware security module, configure the two-factor access control policy, obtain a physically protected private key storage handle, and construct a standardized organizational attribute JSON object according to the administrative responsibilities of the participating parties.

[0064] Furthermore, by calling the key import function through the secure application interface provided by the hardware security module, the private key generated by the national cryptographic SM2 algorithm is stored in encrypted form in the tamper-proof storage area of ​​the hardware security module; then, a two-factor access control policy is configured, which requires simultaneous verification of the physical smart card and biometrics to access the private key, generating a physically protected private key storage handle, and extracting permission attribute fields according to the administrative responsibilities of the participants in the government system to construct a standardized organizational attribute JSON object.

[0065] S1.3 Combine the unique identifier, public key, and standardized institutional attribute JSON object into a registration transaction data structure.

[0066] Furthermore, the specific process of combining the unique identifier, public key, and standardized organizational attribute JSON object into the registration transaction data structure is as follows: First, extract the complete string of the unique identifier generated by the hash algorithm, obtain the compressed format binary data of the public key generated by the national cryptographic SM2 algorithm, and the serialized byte stream of the standardized organizational attribute JSON object containing fields for department level, data category, and operation permission. Then, according to the transaction data format defined by the consortium blockchain smart contract, place the unique identifier as an index field in the structure header, place the public key data as an authentication field in the structure middle, place the standardized organizational attribute JSON object as a permission declaration field in the structure tail, and finally add a version number field and a data length field to form the complete registration transaction data structure.

[0067] S1.4 Based on the registered transaction data structure, the registration contract deployed on the consortium blockchain is used to obtain the call results of block height and transaction hash. The call results of block height and transaction hash are verified by a CA institution. The root certificate is used to perform SM2 signing to obtain a digital certificate.

[0068] Furthermore, based on the registration transaction data structure, the registration contract function deployed on the consortium blockchain is called. The registration transaction data structure is passed as an input parameter to the registration method of the registration contract. After the smart contract code is executed, a call result containing the block height and transaction hash is generated on the blockchain network. The certificate authority node listens to the blockchain network to obtain the call result, verifies whether the block height conforms to the current chain height range and whether the transaction hash is valid. After the verification is successful, the certificate authority uses its root certificate private key to sign the public key field and the institution attribute field in the registration transaction data structure using the national cryptographic SM2 algorithm to obtain the digital certificate.

[0069] S1.5 Integrate the unique identity identifier, public key, standardized organization attribute JSON object, and digital certificate to generate an identity credential package.

[0070] Furthermore, the specific process of integrating a unique identifier, public key, standardized organizational attribute JSON object, and digital certificate to generate an identity credential package is as follows: The unique identifier generated by the hash algorithm is used as the credential index field; the public key generated by the national cryptographic SM2 algorithm is used as the authentication field; the standardized organizational attribute JSON object containing departmental levels and data classifications is used as the permission declaration field; and the digital certificate issued by the CA is used as the trust anchor field. The four fields are then assembled into a structured data block in sequence using the ASN.1 encoding rule. An SM3 hash value is calculated on the data block as an integrity check code, ultimately generating the identity credential package.

[0071] S2. Based on the attribute information in the identity credential package, the participating parties collaboratively generate quantum-resistant dynamic attribute-based encryption key fragments through a secure multi-party computation protocol.

[0072] S2.1 The government data management unit parses the institutional attribute information in the identity credential package and converts it into a standardized binary attribute vector. Based on the standardized binary attribute vector, each participating party collaboratively generates a cryptographic public matrix and an attribute association matrix through a secure multi-party protocol.

[0073] Furthermore, the government data management unit parses the organizational attribute information in the identity credential package, extracts the department level and data classification fields from the standardized organizational attribute JSON object; converts each attribute field into a fixed-length binary attribute vector using the SHA3 hash function; based on their respective binary attribute vectors, each participating party collaboratively calculates the matrix product using the additive homomorphic encryption feature of the secure multi-party computation protocol to generate a cryptographic common matrix; and continues to calculate the attribute association matrix using the multiplication sub-protocol of the secure multi-party computation protocol, ultimately obtaining a complete combination of the cryptographic common matrix and the attribute association matrix.

[0074] S2.2. Obtain the real-time weight value based on the current timestamp and the initial weight.

[0075] Furthermore, the process of calculating the real-time weight value based on the current timestamp and the initial weight is as follows: obtain the precise time difference from the authorization start time to the current time, and substitute this time difference into the exponential decay function for calculation; the exponential decay function uses the initial weight as the base value and a fixed decay coefficient as the proportional constant, and obtains the real-time weight value through the negative exponentiation of the natural constant; the real-time weight value exhibits continuous decay characteristics over time, and finally outputs the real-time weight value.

[0076] S2.3 Using the attribute association matrix and real-time weight values, the master key is securely calculated via MPC to generate quantum-resistant dynamic attribute base encryption key fragments.

[0077] Specifically, the expression is,

[0078] sk=[A|B0+∑w·x i B i ] -1 ·G;

[0079] Where sk is the quantum-resistant dynamic property basis encryption key fragment, A is the common parameter matrix, B0 is the attribute correlation matrix, w is the dynamic weight function, and x i B is the binary encoded value of the i-th attribute. i Let G be the correlation matrix corresponding to the i-th attribute, and G be the fixed trapdoor matrix in lattice cipher.

[0080] S3. Distribute secrets to all participants using threshold secret sharing technology.

[0081] S3.1. Add discrete Gaussian noise to the fragmented encryption key of the quantum dynamic property base to obtain a noisy key.

[0082] Furthermore, random noise values ​​are obtained from a cryptographically secure discrete Gaussian distribution sampler. These random noise values ​​have zero mean and a preset standard deviation parameter. The quantum-resistant dynamic property base encryption key is fragmented and modulo-added with the discrete Gaussian noise values ​​in a finite field to obtain a noisy key.

[0083] S3.2 Construct a polynomial based on the noisy key to obtain the polynomial coefficient vector.

[0084] Specifically, the expression is,

[0085] f(z) = sk″ + a1z + ... + a t-1 z m-1 ;

[0086] Where f(z) is the polynomial coefficient vector, z is the input variable, sk″ is the noisy key, a1 is the random coefficient vector, and a t-1 Let z be the (t-1)th coefficient of the random coefficient vector. k-1 Let m be the input variable raised to the power of m-1, t be the threshold value, and m be the maximum power.

[0087] S3.3. Use the Shamir threshold secret sharing method to obtain the key fragments of each participant, and use the additive homomorphic encryption scheme to encrypt the key fragments to obtain the encrypted fragment set.

[0088] Furthermore, the specific process of obtaining the key fragments for each participant using the Shamir threshold secret sharing method is as follows: construct a t-1 degree polynomial based on the noisy key, substitute the unique number of each participant into the polynomial to calculate the corresponding key fragment value; then use the Paillier additive homomorphic encryption scheme to encrypt each key fragment value using the receiver's public key to generate an encrypted fragment set.

[0089] S3.4 Each participant decrypts and verifies the encrypted key fragment set, and writes the verified key fragment into the hardware security module.

[0090] s j =f·(j);

[0091] Among them, s j This is a key fragment for the j-th participant, where j is the unique identifier of the participant, and f is a polynomial.

[0092] S4. The FPGA acceleration card is used to receive quantum-resistant dynamic property base encryption key fragments, and multi-party secure computation protocol is executed within the hardware secure enclave to obtain decision results and ciphertext fragments of permission tokens.

[0093] S4.1. Load the physically isolated TrustZone secure enclave firmware onto the FPGA, generate a unique chip key, and use Paillier homomorphic decryption to process the received encrypted fragment set to obtain the plaintext key fragment.

[0094] Furthermore, the process of loading physically isolated TrustZone secure enclave firmware using FPGA is as follows: the digitally signed TrustZone secure enclave firmware image is written into the physically isolated secure area through the FPGA configuration interface, triggering a physically unclonable function to generate a chip-unique key based on the chip's physical characteristics; then, within the secure enclave, the hardware implementation module of the Paillier homomorphic decryption algorithm is called to decrypt the encrypted fragments in the encrypted fragment set using the chip-unique key, and the plaintext key fragment is recovered through modular exponentiation and modular inversion; thus, the plaintext key fragment is obtained.

[0095] S4.2 Reconstruct the noisy key over a finite field using Lagrange interpolation to obtain a verified set of shards. The FPGA's built-in true random number generator generates a triple pool in parallel.

[0096] Furthermore, the process of reconstructing the noisy key over a finite field using Lagrange interpolation involves collecting a set of plaintext key fragments that at least reach a threshold value. The participant number corresponding to each plaintext key fragment is used as the x-coordinate of the interpolation point, and the fragment value is used as the y-coordinate. The function value of the zero point is calculated using the Lagrange interpolation formula to reconstruct the complete noisy key. At the same time, it is verified whether each interpolation point satisfies the polynomial constraint relationship. The verified plaintext key fragments form a set of verified fragments. The true random number generator built into the FPGA generates multiple sets of Beaver triples in parallel based on the quantum noise source.

[0097] S4.3 Calculate the encrypted matching result of request attributes and dynamic weights based on the GMW protocol, and decrypt the encrypted matching result using the Shamir algorithm to obtain the decision result and the ciphertext fragment of the permission token.

[0098] Specifically, the expression is,

[0099]

[0100] Where E(Match) is the encrypted matching result, E(x) i Let be the encrypted value of the i-th attribute, E(w) i ) represents the dynamic weight encryption value of the i-th attribute, E(r) is the encryption vector, n is the total number of attributes, and i is the attribute index.

[0101] Specifically, the expression is,

[0102]

[0103] Where Match is the decrypted matching result, q is the modulus, and k is the node index in the Lagrange interpolation.

[0104] S5. Receive the decision result and encrypted fragment of the permission token through the verification smart contract on the consortium blockchain, recover the complete permission token through threshold decryption and verify its validity, and generate an authorization record.

[0105] S5.1. By verifying the smart contract, listen to the blockchain event log, obtain the encrypted decision result and the transaction request of the token fragment, obtain the raw data packet to be processed, use the public key to verify the digital signature of the transaction request of the token fragment, and obtain the data packet with the signature verified.

[0106] Furthermore, the verification smart contract continuously scans newly generated blocks in the blockchain network, identifies transaction request events containing cryptographic decision results and token fragments, extracts complete cryptographic data payloads from blockchain transaction data, assembles them into raw data packets to be processed, verifies the digital signature in the transaction request using the pre-stored public key of the supervisory node, and checks the matching between the signature and the transaction hash using the national cryptographic SM2 signature verification algorithm. Transaction request data that passes verification is marked as a data packet with a verified signature.

[0107] S5.2 The smart contract collects encrypted permission token fragments from participating nodes to obtain a set of fragments that meet the threshold requirements. It reconstructs the noisy key using the Shamir secret sharing algorithm, decrypts it to obtain the plaintext permission token, and uses a multi-dimensional joint verification method to verify the plaintext permission token to obtain the verified plaintext permission token content.

[0108] Furthermore, the smart contract collects encrypted permission token fragments from participating nodes. When the number of collected encrypted permission token fragments reaches a preset threshold, a set of fragments that meet the threshold requirements is formed. The Shamir secret sharing algorithm is used to reconstruct the encrypted permission token fragments in the set of fragments that meet the threshold requirements, recovering the noisy key. The noisy key is used to decrypt the encrypted permission token fragments to obtain the plaintext permission token. A multi-dimensional joint verification method is used to verify the plaintext permission token. The multi-dimensional joint verification method includes consistency and validity verification of the identity information, timestamp, access policy, and digital signature in the plaintext permission token. Only when the verification of all dimensions passes is the plaintext permission token deemed valid, and the verified plaintext permission token content is obtained.

[0109] S5.3. Generate an authorization record based on the content of the verified token.

[0110] Furthermore, the permission declaration field and data identifier field in the verified token content are parsed to extract the access permission list and validity period information; the extracted permission information is combined with the data resource identifier to form a structured record, and the current timestamp and blockchain block height are added as audit information; the permission entries are hashed using a Merkle tree structure to generate a root hash value, and finally a complete authorization record containing data hash, permission policy and audit trail is formed.

[0111] S6. Configure the access control policy for edge computing nodes based on the authorization records, and respond to encrypted queries from data requesters using the Uninvited Transport Protocol.

[0112] S6.1 Edge nodes obtain authorization records from the blockchain, extract the allowed operation list, prohibited operation list, and effective conditions from the permission declaration field, and obtain a structured policy object.

[0113] Furthermore, the latest block data containing authorization records is queried through the blockchain node interface, and the permission declaration field in the authorization record is parsed; the specific operation types included in the allowed operation list, the restricted operation types included in the prohibited operation list, and the time constraints and attribute constraints included in the effective conditions are extracted from the permission declaration field; these extracted elements are combined into a structured policy object containing complete permission information.

[0114] S6.2. Convert the structured policy object into a policy language file for the Linux security enhancement module, generate a binary policy file containing type enforcement rules and access vectors, and obtain the policy module. The secure loading interface loads the policy module into the Linux security module, obtains the policy activation status code, and uses the voice key to symmetrically decrypt the encrypted query data submitted by the requester to obtain the plaintext query statement. Compare the operation fields in the query statement with the list of allowed operations in the policy object to obtain a securely filtered query syntax tree. Extract the target data index value from the securely filtered query syntax tree.

[0115] Furthermore, the allowed and prohibited operation lists in the structured policy object are parsed to generate corresponding type enforcement rule declarations and access vector definitions. The policy language file is then compiled into a binary policy module using a policy compiler. This policy module contains machine code representations of the type enforcement rules and access vectors. The policy module is loaded into the Linux security module via a secure loading interface, and a policy activation status code is returned indicating the loading result. The encrypted query data submitted by the requester is decrypted using the SM4 algorithm (China's national cryptographic standard) using a session key to obtain the plaintext query statement. The operation fields in the plaintext query statement are compared item by item with the allowed operation list in the structured policy object, filtering out unauthorized operations to generate a securely filtered query syntax tree. Finally, the specific numerical value of the target data index is parsed from the WHERE clause of the securely filtered query syntax tree.

[0116] S6.3 The requester calculates the blinded request parameters based on the target data index value, combined with the elliptic curve generator and random number, using the elliptic curve blinding algorithm, and obtains the unintentional transport protocol request packet.

[0117] Specifically, the expression is,

[0118] c = g σ ·h r modp

[0119] Where c is the blinding request parameter, g is the elliptic curve base point, σ is the target data index value, and h is the elliptic curve point of the receiver's public key.

[0120] S6.4 Edge nodes use their own private keys to hash and obfuscate all data items, generating corresponding response data sets. The requester uses pre-shared elliptic curve parameters and its own selected bit information to extract and decrypt the target data item from the response packet, obtaining the plaintext query result.

[0121] Furthermore, the national cryptographic SM3 hash algorithm is used in conjunction with the edge node's private key to calculate the message authentication code for each data item. The original data item and the hash value are XORed to achieve obfuscation, generating a response data set containing all obfuscated data items. This set maintains the original data item order. The requester uses pre-shared elliptic curve generators and its own selection bit information to restore the obfuscation factor through elliptic curve dot product operations. It then extracts the obfuscated data corresponding to the target position from the response data set and removes the obfuscation effect through a second XOR operation to obtain the plaintext query result.

[0122] S7. The audit node monitors the access logs of the data requester, dynamically adjusts the attribute weight parameters through a secure multi-party computation protocol, and synchronizes them to the quantum-resistant dynamic attribute base encryption key fragment.

[0123] S7.1 The audit node receives the encrypted access log stream from the edge computing node via the TLS1.3 protocol, obtains the encrypted log block with timestamp, compares the Merkle root hash of the encrypted log block with the blockchain evidence, and outputs the standardized log data that has passed the verification.

[0124] Furthermore, a TLS 1.3 secure channel based on the national cryptographic algorithm is established to receive encrypted access log data streams transmitted in real time from edge computing nodes. The received data stream is divided into blocks according to fixed time windows, and a timestamp accurate to the millisecond is added to each data block to form a timestamped encrypted log block. The Merkle root hash value is calculated for each timestamped encrypted log block, and the root hash value is compared and verified with the corresponding hash record pre-stored on the blockchain. Only encrypted log blocks that pass the consistency verification are decrypted to obtain verified standardized log data.

[0125] S7.2 Each audit node aggregates log feature values ​​through a secure multi-party protocol to obtain encrypted statistical results.

[0126] Furthermore, each audit node extracts key feature values ​​from standardized log data, including access frequency, operation type distribution, and time series patterns. The Paillier additive homomorphic encryption algorithm is used to encrypt the feature values ​​of each node. Through the summation operation rules of the secure multi-party computation protocol, the encrypted feature values ​​of all nodes are aggregated in the ciphertext state to generate encrypted statistical results containing global statistical features.

[0127] S7.3. Based on the statistical results, identify abnormal access behaviors that exceed the 3σ range, obtain risk event reports, and derive weight adjustment gradients based on the risk reports through the MPC protocol.

[0128] Furthermore, anomaly data points deviating from the mean by more than three standard deviations are identified through a secure comparison protocol. The identified abnormal access behaviors are classified according to risk level, generating risk event reports that include timestamps, risk types, and impact levels. Based on the risk indicators in the risk event reports, the weight adjustment gradient is obtained through the gradient descent algorithm of a secure multi-party protocol. Finally, a weight update vector with homomorphic encryption is output, which maintains the privacy of the weight parameters of each participating party.

[0129] S7.4. Use weighted gradient to dynamically adjust the attribute association matrix to obtain the adjusted matrix parameter set. Based on the adjusted matrix parameter set, generate a new key shard through threshold secret sharing. Write the Merkle root hash of the new key shard into the smart contract to obtain the policy update transaction receipt.

[0130] Furthermore, the encrypted weight update vector is decrypted and applied to the original attribute association matrix. The matrix element values ​​are updated through matrix addition to obtain the adjusted matrix parameter set. Based on the adjusted matrix parameter set, the Shamir threshold secret sharing method is used to generate new key fragments to ensure that the threshold reconstruction requirements are met. The Merkle root hash value of all new key fragments is obtained. The root hash value is used as a parameter to call the update function of the blockchain smart contract. After the smart contract executes successfully, it returns a strategy update transaction receipt containing the transaction hash and block height.

[0131] This embodiment also provides a computer device applicable to the dynamic authorization management method for government data based on secure multi-party computation, comprising: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to implement the dynamic authorization management method for government data based on secure multi-party computation as proposed in the above embodiment.

[0132] The computer device can be a terminal, comprising a processor, memory, communication interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, carrier networks, NFC (Near Field Communication), or other technologies. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad on the computer device's casing, or an external keyboard, touchpad, or mouse.

[0133] This embodiment also provides a storage medium storing a computer program. When executed by a processor, the program implements the dynamic authorization management method for government data based on secure multi-party computation as proposed in the above embodiments. The storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read Only Memory (EPROM), Programmable Red-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk.

[0134] In summary, this invention assigns unique identifiers to each participant and generates asymmetric key pairs using the national cryptographic SM2 algorithm. The public key and institutional attribute information are registered to a consortium blockchain smart contract to generate an identity credential package. Based on the attribute information in the identity credential package, a quantum-resistant dynamic attribute-based encrypted key fragment is collaboratively generated through a secure multi-party computation protocol and distributed using threshold secret sharing technology. An FPGA accelerator card executes the multi-party secure computation protocol within a hardware-secure enclave to obtain the decision result and encrypted fragments of the permission token. Threshold decryption and token verification are implemented through a consortium blockchain verification smart contract, generating authorization records. Access control policies for edge computing nodes are configured based on these authorization records, and an unintentional transmission protocol is used to respond to data queries. Access logs are monitored through audit nodes, and attribute weight parameters are dynamically adjusted and synchronized to the key fragments.

[0135] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A dynamic authorization management method for government data based on secure multi-party computation, characterized in that: include, Each participant is assigned a unique identity identifier, and an asymmetric key pair is generated using the national cryptographic SM2 algorithm. The public key and the institution attribute information are registered to the consortium blockchain smart contract to generate an identity credential package. Based on the attribute information in the identity credential package, the participants collaboratively generate quantum-resistant dynamic attribute-based encryption key fragments through a secure multi-party computation protocol, and distribute them to each participant using threshold secret sharing technology. An FPGA acceleration card is used to receive quantum-resistant dynamic property base encryption key fragments, and a multi-party secure computation protocol is executed within a hardware secure enclave to obtain decision results and ciphertext fragments of authorization tokens. The decision result and encrypted fragment of the permission token are received through the verification smart contract on the consortium blockchain. The complete permission token is recovered by decryption through the threshold and its validity is verified to generate an authorization record. Configure access control policies for edge computing nodes based on authorization records, and respond to encrypted queries from data requesters using unobtrusive transport protocols; The audit node monitors the access logs of the data requester, dynamically adjusts the attribute weight parameters through a secure multi-party computation protocol, and synchronizes them to the quantum-resistant dynamic attribute base encryption key fragment.

2. The dynamic authorization management method for government data based on secure multi-party computation as described in claim 1, characterized in that: Each participant is assigned a unique identifier, and an asymmetric key pair is generated using the SM2 algorithm (China's national cryptographic standard). The public key and institutional attribute information are registered to the consortium blockchain smart contract to generate an identity credential package, including the following steps. The government data management unit uses a hash algorithm to generate a unique identity for each participant and uses the national cryptographic SM2 algorithm to generate an asymmetric key pair on an elliptic curve to obtain a private key and a public key. Write the private key into the hardware security module, configure a two-factor access control policy, obtain a physically protected private key storage handle, and construct a standardized organizational attribute JSON object based on the administrative responsibilities of the participating parties. The unique identifier, public key, and standardized institutional attribute JSON object are combined into a registration transaction data structure; Based on the registered transaction data structure, the registration contract deployed on the consortium blockchain obtains the call results of block height and transaction hash. The CA institution verifies the call results of block height and transaction hash, and the root certificate pair is used to perform SM2 signing to obtain a digital certificate. Integrate unique identifiers, public keys, standardized organization attribute JSON objects, and digital certificates to generate an identity credential package.

3. The dynamic authorization management method for government data based on secure multi-party computation as described in claim 2, characterized in that: Based on the attribute information in the identity credential package, the participating parties collaboratively generate quantum-resistant dynamic attribute-based encryption key fragments through a secure multi-party computation protocol. Includes the following steps, The government data management unit parses the institutional attribute information in the identity credential package and converts it into a standardized binary attribute vector. Based on the standardized binary attribute vector, all participating parties collaboratively generate a cryptographic public matrix and an attribute association matrix through a secure multi-party protocol. Based on the current timestamp and the initial weight, the real-time weight value is obtained; Using the attribute association matrix and real-time weight values, a quantum-resistant dynamic attribute base encryption key is generated by securely calculating the master key via MPC.

4. The dynamic authorization management method for government data based on secure multi-party computation as described in claim 3, characterized in that: Distributing secrets to all participants using threshold secret sharing technology includes the following steps: To counteract quantum dynamic property basis encryption key fragmentation, discrete Gaussian noise is added to the fragments to obtain a noisy key; A polynomial is constructed based on the noisy key, and the polynomial coefficient vector is obtained. The key fragments for each participant are obtained using the Shamir threshold secret sharing method, and the key fragments are encrypted using an additive homomorphic encryption scheme to obtain an encrypted fragment set. Each participant decrypts and verifies the encrypted fragment set, and writes the verified key fragment into the hardware security module.

5. The dynamic authorization management method for government data based on secure multi-party computation as described in claim 4, characterized in that: An FPGA accelerator card is used to receive quantum-resistant dynamic property-based encryption key fragments. A multi-party secure computation protocol is executed within a hardware-secure enclave to obtain the decision result and ciphertext fragments of the access token. Includes the following steps, The TrustZone secure enclave firmware, which is physically isolated, is loaded onto the FPGA to generate a unique chip key. The received encrypted fragment set is then processed using Paillier homomorphic decryption to obtain the plaintext key fragment. The noisy key is reconstructed by Lagrange interpolation over a finite field to obtain a verified set of shards. The FPGA's built-in true random number generator generates a triple pool in parallel. The encrypted matching result of the request attribute and dynamic weight is calculated based on the GMW protocol. The encrypted matching result is decrypted using the Shamir algorithm to obtain the decision result and the ciphertext fragment of the permission token.

6. The dynamic authorization management method for government data based on secure multi-party computation as described in claim 5, characterized in that: The process involves receiving the decision result and encrypted fragments of the authorization token via a verification smart contract on the consortium blockchain, decrypting the complete authorization token using a threshold decryption method, verifying its validity, and generating an authorization record. This includes the following steps: By verifying the smart contract, listening to the blockchain event log, obtaining the encrypted decision results and the transaction request of the token fragment, the raw data packet to be processed is obtained. The digital signature of the transaction request of the token fragment is verified using the public key, and the data packet with the signature verified is obtained. The smart contract collects encrypted permission token fragments from participating nodes to obtain a set of fragments that meet the threshold requirements. It then reconstructs the noisy key using the Shamir secret sharing algorithm, decrypts it to obtain the plaintext permission token, and verifies the plaintext permission token using a multi-dimensional joint verification method to obtain the verified plaintext permission token content. Generate an authorization record based on the verified token content.

7. The dynamic authorization management method for government data based on secure multi-party computation as described in claim 6, characterized in that: Configure access control policies for edge computing nodes based on authorization records, and respond to encrypted queries from data requesters using an unobtrusive transport protocol. Includes the following steps, Edge nodes obtain authorization records from the blockchain, extract the list of allowed operations, the list of prohibited operations, and the effective conditions from the permission declaration fields, and obtain a structured policy object; The structured policy object is converted into a policy language file of the Linux security enhancement module, generating binary policy files with type enforcement rules and access vectors to obtain the policy module. The secure loading interface loads the policy module into the Linux security module, obtains the policy activation status code, uses the session key to symmetrically decrypt the encrypted query data submitted by the requester to obtain the plaintext query statement, compares the operation fields in the query statement with the list of allowed operations in the policy object to obtain the securely filtered query syntax tree, and extracts the target data index value from the securely filtered query syntax tree. The requester calculates the blinded request parameters based on the target data index value, combined with the elliptic curve generator and random number, using the elliptic curve blinding algorithm, and obtains the unintentional transport protocol request packet. Edge nodes use their own private keys to hash and obfuscate all data items, generating a corresponding set of response data. The requester uses pre-shared elliptic curve parameters and its own selected bit information to extract and decrypt the target data item from the response packet, obtaining the plaintext query result.

8. The dynamic authorization management method for government data based on secure multi-party computation as described in claim 7, characterized in that: The audit node monitors the access logs of data requesters, dynamically adjusts attribute weight parameters through a secure multi-party computation protocol, and synchronizes them to the quantum-resistant dynamic attribute base encryption key fragment. Includes the following steps, The audit node receives the encrypted access log stream from the edge computing node via the TLS 1.3 protocol, obtains the timestamped encrypted log block, compares the Merkle root hash of the encrypted log block with the blockchain evidence, and outputs the verified standardized log data. Each audit node aggregates log feature values ​​through a secure multi-party protocol to obtain encrypted statistical results; Based on the statistical results, abnormal access behaviors exceeding the 3σ range are identified, and risk event reports are obtained. Based on the risk reports, the weight adjustment gradient is derived through the MPC protocol. The attribute association matrix is ​​dynamically adjusted using weighted gradient adjustment to obtain the adjusted matrix parameter set. Based on the adjusted matrix parameter set, a new key shard is generated through threshold secret sharing. The Merkle root hash of the new key shard is written into the smart contract to obtain the policy update transaction receipt.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, it implements the steps of the dynamic authorization management method for government data based on secure multi-party computation as described in any one of claims 1 to 8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by the processor, it implements the steps of the dynamic authorization management method for government data based on secure multi-party computation as described in any one of claims 1 to 8.

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