Data processing method and related device

Abstract

A data processing method, comprising: a second client extracts a public key of a second user from an identity certificate of the second user, uses the public key of the second user to hierarchically encrypt data to obtain a ciphertext, and stores the ciphertext and the identity certificate of the second user to a blockchain network; and a first client acquires the ciphertext and the identity certificate of the second user from the blockchain network, and uses a root certificate to verify the legitimacy of the identity certificate of the second user. When the verification is passed, the first client extracts first derived information from an identity certificate of a first user and extracts second derived information from the identity certificate of the second user. The derived information indicates a derivation path of an identity certificate. The first client determines a private key of the second user on the basis of the derived information and a private key of the first user, and on the basis of the private key of the second user, decrypts the ciphertext to obtain the data. In the method, an authentication mechanism of the identity certificate is used for authenticating the public key, thereby resolving an identity trust issue and achieving hierarchical visibility of data.

Description

Data processing method and related device

[0001] The present application claims priority to the Chinese Patent Application No. 202410809099.3, filed on June 20, 2024, entitled "A blockchain data processing method and related device", and to the Chinese Patent Application No. 202411214738.8, filed on August 30, 2024, entitled "A data processing method and related device", both of which are incorporated herein by reference in their entirety. TECHNICAL FIELD

[0002] The present application relates to the field of blockchain technology, and in particular to a data processing method, a blockchain management system, a computing device cluster, a computer readable storage medium, and a computer program product. BACKGROUND

[0003] The blockchain technology is a new distributed infrastructure and computing paradigm, which uses block chain data structure to verify and store data, uses distributed node consensus algorithm to generate and update data, uses cryptography to ensure the security of data transmission and access, and uses smart contract composed of automatic script code to program and operate data.

[0004] The blockchain technology has broad application prospects in many fields, for example, the blockchain technology can be applied to digital government affairs, financial transaction settlement, etc. In many blockchain application scenarios, there is a need for data visibility division by level. Among them, the visibility division by level can allow users / nodes in the upper layer to view the data of users / nodes in the lower layer, but users / nodes in the lower layer cannot view the data of users / nodes in the upper layer, and the data between users / nodes in the same level is not visible.

[0005] The hierarchical encryption of data can achieve the visibility division by level. Currently, the widely used hierarchical encryption scheme in the industry includes a derived encryption scheme, which uses typical asymmetric public and private keys for encryption and decryption. However, the public key itself cannot solve the authenticity and validity problem, and usually needs to rely on a trusted third-party agency, which introduces a centralized risk and increases the cost, making it difficult to meet business needs. SUMMARY

[0006] The application provides a data processing method, which combines the identity certificate used by a user of a blockchain network when transacting or verifying a signature with derived hierarchical encryption. The hierarchical encryption can use the authentication mechanism of the identity certificate when using information such as a public key to identify the identity of the public key and solve the identity trust problem of the public key. The method does not need to introduce a third-party institution to prove the authenticity and validity of the public key, avoids introducing a centralized risk, reduces costs, and can meet business needs. The application also provides a blockchain management system, a computing device cluster, a computer readable storage medium, and a computer program product corresponding to the above method.

[0007] In a first aspect, the application provides a data processing method. The method is applied to a blockchain management system. The blockchain management system includes a first client, a second client, and a blockchain network. The first client is a client of a first user, and the second client is a client of a second user.

[0008] Specifically, the second client extracts the public key of the second user from the identity certificate of the second user, uses the public key of the second user to hierarchically encrypt data to obtain ciphertext, and stores the ciphertext and the identity certificate of the second user to the blockchain network. Then the first client obtains the ciphertext and the identity certificate of the second user from the blockchain network, verifies the legality of the identity certificate of the second user using the root certificate. When the verification is passed, the first client extracts the first derived information from the identity certificate of the first user and extracts the second derived information from the identity certificate of the second user. The first derived information is used to indicate the derivation path of the identity certificate of the first user, and the second derived information is used to indicate the derivation path of the identity certificate of the second user. The first client determines the private key of the second user according to the first derived information, the second derived information, and the private key of the first user. The first client decrypts the ciphertext according to the private key of the second user to obtain the data.

[0009] The method combines the identity certificate used by a user of a blockchain network when transacting or verifying a signature with derived hierarchical encryption. Specifically, the derivation information of the hierarchical encryption, such as the derivation path of the identity certificate, is automatically attached when generating or creating the identity certificate of the user. The hierarchical encryption can use the authentication mechanism of the identity certificate when using information such as a public key to identify the identity of the public key and solve the identity trust problem of the public key. The method does not need to introduce a third-party institution to prove the authenticity and validity of the public key, avoids the centralized risk, reduces costs, and can meet business needs. Moreover, the user does not need to distribute and manage the special key used for hierarchical encryption, simplifies key management, and is more secure. In addition, the data encrypted by the user using the public key extracted from the identity certificate can be naturally monitored by the upper user, solving the problem of insufficient supervision and building a blockchain identity system with supervision attributes.

[0010] In some possible implementation manners, the first client can determine the hierarchical relationship between the first user and the second user according to the first derived information and the second derived information, and then the first client can extract the user identifier of the second user from the second derived information according to the hierarchical relationship. Then the first client can determine the private key of the second user by the derivation algorithm according to the user identifier of the second user and the private key of the first user.

[0011] In the method, the upper-layer user can derive the private key of the lower-layer user based on the hierarchical relationship between the users, and the data of the lower-layer user is visible to the upper-layer user, thereby implementing the hierarchical division of data visibility. Moreover, the method does not require the user to perform additional key management, simplifies the user operation, and reduces the user cost.

[0012] In some possible implementation manners, the first client can splice the private key of the first user, the chain code of the first user, and the user identifier of the second user to obtain a splicing result. The first client can perform a hash operation on the splicing result to obtain the private key of the second user. The chain code of the first user can be a random number, for example, a 256-bit random number. By combining the user identifier and the random number to generate the private key of the lower-layer user, it can be prevented that the private key of the lower-layer user depends on the private key of the upper-layer user, and the security of the private key is further improved.

[0013] In the method, the first user can be the direct upper-layer user of the second user, and the first user can derive the private key of the second user through one-time key generation, thereby enabling efficient decryption of the data of the second user.

[0014] In some possible implementation manners, the first client can determine the private key of the third user by the derivation algorithm according to the private key of the first user and the user identifier of the third user, and the third user is a child user of the first user. The first client can determine the private key of the second user by the derivation algorithm according to the private key of the third user and the user identifier of the second user, and the second user is a child user of the third user.

[0015] In the method, the first user can be a non-direct upper-layer user (for example, an indirect upper-layer user) of the second user, and the first user can derive the private key of the lower-layer user layer by layer until the private key of the second user is derived. In this way, the upper-layer user can view and supervise the data of the lower-layer user at any hierarchical level, thereby implementing the hierarchical division of data visibility.

[0016] In some possible implementation manners, the second derived information is generated according to the first derived information and the user identifier of the second user. For example, the second derived information can be cumulatively generated from the first derived information and the user identifier of the second user, and the first derived information can be cumulatively generated from the user identifier of the first user and the user identifier of the upper-layer user of the first user.

[0017] The method generates derived information by accumulating the user identifier, can realize extraction of the hierarchical relationship based on the derived information, and further performs key management based on the hierarchical relationship, thereby laying a foundation for hierarchical division of data visibility.

[0018] In some possible implementation manners, the first client can extract the first derived information from an extension field of the identity certificate of the first user. In this way, the identity certificate can be combined with the hierarchical encryption without changing the structure of the identity certificate, and higher compatibility and usability can be achieved.

[0019] In a second aspect, the present application provides a blockchain management system. The blockchain management system includes a first client, a second client and a blockchain network, the first client is a client of a first user, and the second client is a client of a second user.

[0020] The second client is configured to extract a public key of the second user from an identity certificate of the second user, perform hierarchical encryption on data using the public key of the second user to obtain ciphertext, and store the ciphertext and the identity certificate of the second user to the blockchain network.

[0021] The first client is configured to obtain the ciphertext and the identity certificate of the second user from the blockchain network, and verify the legality of the identity certificate of the second user using a root certificate.

[0022] The first client is further configured to, when the verification is passed, extract a first derived information from the identity certificate of the first user and extract a second derived information from the identity certificate of the second user, the first derived information being used to indicate a derivation path of the identity certificate of the first user, and the second derived information being used to indicate a derivation path of the identity certificate of the second user.

[0023] The first client is further configured to determine a private key of the second user according to the first derived information, the second derived information and the private key of the first user.

[0024] The first client is further configured to decrypt the ciphertext to obtain the data according to the private key of the second user.

[0025] In some possible implementation manners, the first client is specifically configured to:

[0026] determine a hierarchical relationship of the first user and the second user according to the first derived information and the second derived information;

[0027] extract a user identifier of the second user from the second derived information according to the hierarchical relationship;

[0028] According to the user identifier of the second user and the private key of the first user, the private key of the second user is determined through a derivation algorithm.

[0029] In some possible implementation manners, the first client is specifically configured to:

[0030] The private key of the first user and chain code of the first user, and the user identifier of the second user are spliced to obtain a splicing result.

[0031] The splicing result is subjected to a hash operation to obtain the private key of the second user.

[0032] In some possible implementation manners, the first client is specifically configured to:

[0033] According to the private key of the first user and a user identifier of a third user, the private key of the third user is determined through a derivation algorithm, the third user being a child user of the first user.

[0034] According to the private key of the third user and a user identifier of a second user, the private key of the second user is determined through a derivation algorithm, the second user being a child user of the third user.

[0035] In some possible implementation manners, the second derivation information is generated according to the first derivation information and the user identifier of the second user.

[0036] In some possible implementation manners, the first client is specifically configured to:

[0037] First derivation information is extracted from an extension field of the identity certificate of the first user.

[0038] In a third aspect, the present application provides a computing device cluster. The computing device cluster includes at least one computing device, and the at least one computing device includes at least one processor and at least one memory. The at least one processor and the at least one memory are in communication with each other. The at least one processor is configured to execute instructions stored in the at least one memory, so that the computing device or the computing device cluster performs the data processing method according to the first aspect or any implementation manner of the first aspect.

[0039] In a fourth aspect, the present application provides a computer readable storage medium, and the computer readable storage medium stores instructions. The instructions instruct the computing device or the computing device cluster to perform the data processing method according to the first aspect or any implementation manner of the first aspect.

[0040] In a fifth aspect, the present application provides a computer program product comprising instructions which, when executed on a computing device or a cluster of computing devices, cause the computing device or the cluster of computing devices to perform the data processing method according to the first aspect or any implementation manner of the first aspect.

[0041] On the basis of implementation manners of the aspects provided by the present application, further combinations can be made to provide more implementation manners. BRIEF DESCRIPTION OF DRAWINGS

[0042] In order to more clearly illustrate the technical method of the present application, the drawings required for use will be briefly introduced below.

[0043] FIG. 1A is a schematic diagram of a conventional derivation provided by the present application;

[0044] FIG. 1B is a schematic diagram of a reinforced derivation provided by the present application;

[0045] FIG. 2 is a schematic diagram of an architecture of a blockchain management system provided by the present application;

[0046] FIG. 3 is an interaction flowchart of a data processing method provided by the present application;

[0047] FIG. 4 is a flowchart of data encryption and decryption in a data processing method provided by the present application;

[0048] FIG. 5 is a structural schematic diagram of a computing device provided by the present application;

[0049] FIG. 6 is a structural schematic diagram of a cluster of computing devices provided by the present application;

[0050] FIG. 7 is a structural schematic diagram of another cluster of computing devices provided by the present application. DETAILED DESCRIPTION

[0051] The terms “first” and “second” in the embodiments of the present application are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with “first” and “second” can explicitly or implicitly include one or more of the features.

[0052] First, some technical terms involved in the embodiments of the present application are introduced.

[0053] A blockchain network is a technical infrastructure that provides ledger and smart contract services for applications, specifically a point-to-point network system that establishes and stores a large transaction data chain through technologies such as cryptography and consensus mechanisms. The blockchain network can be divided into a public blockchain (public chain), a consortium blockchain (consortium chain), or a completely private blockchain (private chain) according to data access permissions. Among them, the data access threshold of the public chain is low, and any user can access it through a computer, the data access permission of the consortium chain is open to organizations or institutions in the consortium, and the data access permission of the private chain is open to specified organizations or institutions. Since the data is disclosed in the blockchain network, considering the security requirements, the data can be divided into levels of visibility.

[0054] Hierarchical Encryption is an algorithm model for data protection, which realizes hierarchical data access control, thereby realizing the division of data into levels of visibility. In the hierarchical encryption model, a master key is used to generate multiple sub-keys, each sub-key has separate access permissions and encryption levels. The highest level key can access all levels of data, while the lower level key can only access the level or below level data corresponding to the key. Based on this, each user can hold their own public and private keys, where the lower level user's key can be generated by the upper level user, and the lower level user's encrypted data can be decrypted by the upper level user using their own private key, thereby achieving the purpose of data supervision. At the same time, the upper level user does not need to keep a large number of lower level user's private keys, reducing the difficulty of key management and the risk of private key leakage.

[0055] Currently, the industry usually uses hierarchical encryption based on derivation to realize the division of data into levels of visibility. Typical implementations of hierarchical encryption based on derivation can include hierarchical deterministic wallets or hierarchical deterministic wallets. Hierarchical deterministic wallets allow users to select a seed and deterministically derive a large number of key pairs from the seed in a tree structure. Users do not need to save these derived key pairs, but only need to keep the seed. When using it again, the seed is imported into the wallet, and the identification of all private keys controlled by the assets derived from the seed can be completed.

[0056] Specifically, a user can generate a seed through a mnemonic, hash the seed to obtain a root private key and a root public key, use the root public and private key pairs to derive multiple child public and private key pairs with hierarchical relationships, and use the public and private key pairs for encryption and decryption. In a hierarchical deterministic wallet, in order to prevent sub-keys from relying only on parent keys, each pair of public and private keys corresponds to a 256-bit random number, called a chain code, which is combined and called an extended key. There are two ways to generate a child key: regular derivation and hardened derivation. When the index number i satisfies 0≤i<2 31 , the child key can be generated by regular derivation, and when the index number i satisfies 231 ≤i<2 32 -1, the child key can be generated by reinforcement derivation.

[0057] As shown in FIG. 1A, in the conventional derivation, the child private key and the child chain code are generated by the parent public key, the parent chain code and the index number. As shown in FIG. 1B, in the reinforcement derivation, the child private key and the child chain code are generated by the parent private key, the parent chain code and the index number. The upper user can derive the lower user private key according to the key pair derivation relationship, so as to realize the decryption of the data encrypted by the lower user.

[0058] However, the above scheme uses asymmetric public and private keys for encryption and decryption, which ensures that the data cannot be tampered with, but the public key itself cannot solve the authenticity and validity problems. Therefore, the authenticity and validity of the public key need to be proved by a trusted third-party agency. In this way, the centralization risk is introduced, and the cost is increased, which is difficult to meet the business demand.

[0059] Therefore, the present application provides a data processing method, which combines the identity certificate used by the user of a blockchain network when transacting or verifying a signature with hierarchical encryption based on derivation. Specifically, when generating or creating the identity certificate of the user, the derivation information of the hierarchical encryption, such as the derivation path of the identity certificate, is automatically attached. The hierarchical encryption can use the authentication mechanism of the identity certificate when using the public key and other information to identify the identity of the public key, solving the identity trust problem of the public key. This method does not need to introduce a third-party agency to prove the authenticity and validity of the public key, avoiding the centralization risk, reducing the cost, and being able to meet the business demand. Moreover, the user does not need to distribute and store the special key used for hierarchical encryption, simplifying the key management and being more secure. In addition, the data encrypted by the user using the public key extracted from the identity certificate can be naturally monitored by the upper user, solving the problem of insufficient supervision, and building a blockchain identity system with supervision attributes.

[0060] The data processing method of the present application can be executed by a blockchain management system. In order to facilitate understanding, the system architecture of the blockchain management system of the present application is introduced below in conjunction with the drawings.

[0061] Referring to a schematic diagram of an architecture of a blockchain network management system shown in FIG. 2, the blockchain management system 10 includes a first client 102, a second client 104, and a blockchain network 200. The first client 102 is a client of a first user, and the second client 104 is a client of a second user, where the second user is an upper-level user of the first user, for example, the first user is a common user, and the second user is a supervisor. The blockchain network 200 includes a plurality of blockchain nodes 202. The blockchain nodes 202 can be nodes maintained or managed by organizations. For example, in a consortium chain, the blockchain nodes 202 can be nodes maintained by different organizations. FIG. 2 illustrates an example in which the plurality of blockchain nodes 202 are maintained by an organization A, an organization B, an organization C, and an organization D, respectively. Each organization has a root certificate and a root private key, and the root certificate can be issued by a certificate authority (CA). In the example illustrated in FIG. 2, the organization A has a CA root certificate, denoted as CA a , the organization B has a CA root certificate, denoted as CA b , the organization C has a CA root certificate, denoted as CA c , and the organization D has a CA root certificate, denoted as CA d . Based on the root private key, an identity certificate of a user can be derived, and the identity certificate derived based on the root private key can be verified for legitimacy by the root certificate. Each user holds his own private key and identity certificate, which are used for signing or verifying signatures in on-chain transactions.

[0062] FIG. 2 illustrates an example in which a user of the organization C derives an identity certificate based on the root private key of the organization C. When creating a user and generating a private key and an identity certificate of the user, the private key is no longer randomly generated, but is derived using a hierarchical encryption algorithm inputting derivation information, which can include a derivation path. The derivation path can be expressed by a user identifier of the user and a user identifier of an upper-level user, and thus can also be referred to as identity hierarchy information. The derivation path can be attached to an extension field of the identity certificate, so that the user can perform key derivation based on the derivation path in the extension field, thereby establishing a hierarchical supervision relationship. In a sensitive information encryption scenario, the system no longer needs to separately create and distribute a dedicated encryption key, but directly uses the public key of the identity certificate for encryption and the private key for decryption. An upper-level supervisor can complete decryption of data using his own private key according to the hierarchical encryption algorithm, so that the data is visible to the upper-level user and invisible to the lower-level user, while achieving a strong supervision effect.

[0063] As shown in FIG. 2, the first-tier supervisor can derive the identity certificate of the first-tier supervisor user based on the root certificate of the organization C, the second-tier supervisor can derive the identity certificate of the second-tier supervisor user based on the identity certificate of the first-tier supervisor, and the common user can derive the identity certificate of the common user based on the identity certificate of the second-tier supervisor. It should be noted that the identity certificates of the users at different levels can also be derived by the CA based on the CA root certificate.

[0064] After deriving the identity certificates, the client of the lower-level user can initiate an on-chain transaction. The on-chain transaction can be storing, in the blockchain network, a ciphertext obtained by encrypting data using the public key of the lower-level user. The client of the upper-level user can obtain the ciphertext from the blockchain network, derive the private key of the lower-level user using the private key of the upper-level user, and decrypt the ciphertext to obtain the data.

[0065] The upper-level user can be the first user, and the lower-level user can be the second user. The client of the first user is the first client 102, and the client of the second user is the second client 104.

[0066] The second client 104 is configured to extract the public key of the second user from the identity certificate of the second user, encrypt the ciphertext obtained by layering the data using the public key of the second user, and store the ciphertext and the identity certificate of the second user to the blockchain network 200.

[0067] The first client 102 is configured to obtain the ciphertext and the identity certificate of the second user from the blockchain network 200, extract the first derivation information from the identity certificate of the first user and the second derivation information from the identity certificate of the second user, the first derivation information indicating a derivation path of the identity certificate of the first user, and the second derivation information indicating a derivation path of the identity certificate of the second user, determine the private key of the second user according to the first derivation information, the second derivation information, and the private key of the first user, and decrypt the ciphertext to obtain the data according to the private key of the second user.

[0068] The blockchain management system 10 keeps the functions and use methods of the private key and the identity certificate unchanged in the on-chain transaction scenario, has high usability and compatibility, and when a new user is created, the derived information is input, the identity certificate of the new user is derived based on the derived information, and the private key of the new user is generated. Among them, the derived information is attached to the identity certificate, so that the identity certificate has the ability of hierarchical encryption and decryption. Correspondingly, when the blockchain management system 10 uses the hierarchical encryption function, the private key of the user and the identity certificate (for example, the public key in the identity certificate) are directly used for encryption and decryption, so that automatic supervision of on-chain data can be realized, and efficient supervision can be realized. Moreover, the scheme does not need to use other key pairs, and the user does not need to distribute and store the special key for hierarchical encryption, which simplifies key management and improves security. Moreover, the combination of hierarchical encryption and the identity certificate used for on-chain transaction or signature verification can provide a detection guarantee mechanism for the identity of the owner of sensitive data.

[0069] It should be noted that FIG. 2 illustrates a second user as an example of a second layer supervisor, and in actual application, the second user can also be a first layer supervisor (an indirect upper layer user of the first user). Alternatively, the first user can be a second layer supervisor, and accordingly, the second user is a first layer supervisor. In this case, the specific implementation of deriving the identity certificate and performing hierarchical encryption based on the identity certificate can refer to the related content described in the embodiment of FIG. 2, and will not be repeated here.

[0070] Based on the blockchain management system 10 shown in FIG. 2, the present application further provides a data processing method. The following will be described with reference to the accompanying drawings.

[0071] Referring to the interaction flowchart of the data processing method shown in FIG. 3, the method can include a derived identity certificate stage, a data encryption stage, and a data decryption stage. The different stages will be described in detail below.

[0072] In the derived identity certificate stage, the CA can generate a root private key and a root certificate, for example, a CA root private key and a CA root certificate. The first client 102 derives the private key and the identity certificate of the first user according to the CA root private key. The second client 104 derives the private key and the identity certificate of the second user according to the CA root private key. Among them, the second client 104 can derive the private key and the identity certificate of the first user according to the CA root private key, and then derive the private key and the identity certificate of the second user according to the private key and the identity certificate of the first user.

[0073] The CA root private key and the private keys of the users at different levels can be generated by a derivation algorithm instead of being randomly generated. The derivation algorithm can include, but is not limited to, a Bitcoin Improvement Proposal (BIP)-based derivation algorithm. The BIP is a technical standard for Bitcoin, and a screened technology can be assigned a BIP number. For example, the hierarchical deterministic wallet is added to the BIP through hierarchical screening and is assigned a BIP number BIP32. Based on this, the CA root private key and the private keys of the users at different levels can be generated by a derivation algorithm based on BIP32.

[0074] The CA root certificate and the identity certificates of the users at different levels can be generated by a derivation algorithm. The identity certificate can be in a digital certificate format. In the consortium chain, identity authentication can generally use an X.509 digital certificate under a Public Key Infrastructure (PKI) system. X.509 is a standard that defines the structure and characteristics of digital certificates, and a digital certificate includes at least one of a public key, holder information, issuer information, and a valid period. Under the X.509 standard, each participant has a pair of public and private keys, where the private key is in the hands of the participant himself and is used to sign transactions, and the public key is publicly provided and used to verify transaction signatures. The X.509 digital certificate is a collection of public keys and identity information, signed by a trusted third party (such as a certificate authority CA). Any user who obtains an identity certificate can verify whether the public key and identity information in the identity certificate match by the signature in the identity certificate, and then determine the identity of the transaction initiator.

[0075] In the data encryption phase, the second client 104 extracts the public key of the second user from the identity certificate of the second user, encrypts the plaintext data (denoted as M) to obtain the ciphertext (denoted as C). Then the second client 104 can chain the ciphertext and the identity certificate of the second user {C, Cert n} together. Cert n represents the identity certificate of the second user. The second client 104 can append the identity certificate of the second user after the ciphertext, and then perform the chaining operation. The blockchain network 200 can store the ciphertext and the identity certificate.

[0076] In the data decryption phase, the first client 102 can obtain the ciphertext and the identity certificate of the second user from the blockchain network 200. The first client 102 can also verify the legality of the identity certificate obtained from the blockchain network 200 according to the CA root certificate to confirm the identity. When the verification is passed, the first client 102 can derive the private key of the second user according to the hierarchical encryption algorithm using the private key and the first derived information in the identity certificate of the first user, the second derived information in the identity certificate of the second user, and then use the private key of the second user to decrypt the ciphertext to obtain the data of the plaintext.

[0077] Next, the data encryption and decryption process in the data processing method provided by the present application will be described in detail in combination with the drawings.

[0078] Referring to the flowchart of a data processing method shown in FIG. 4, the method applies a blockchain management system 10, which includes a first client 102, a second client 104 and a blockchain network 200. The first client 102 is a client of a first user, and the second client 104 is a client of a second user. The method includes the following steps:

[0079] S402, the second client 104 extracts the public key of the second user from the identity certificate of the second user.

[0080] The identity certificate of the second user can be derived from the root private key by a derivation algorithm. The private key of the second user can be generated based on the root private key, the public key of the second user can be further generated based on the private key of the second user, and the identity certificate can be generated based on the derivation information, the public key and the private key of the second user.

[0081] Specifically, the second client 104 can generate the private key of the second user by a derivation algorithm according to the private key of the upper user of the second user and the user identifier of the second user. When the derivation algorithm is used to generate the private key of the second user, the chain code of the second user can also be input and output.

[0082] The private key of the second user can be a child private key, denoted as SK child The private key of the upper user of the second user can be a parent private key, denoted as SK parent The chain code of the second user can be a child chain code, denoted as code child The chain code of the upper user of the second user can be a parent chain code, denoted as code parent The user identifier can be an index number (index), and the user identifier of the second user can be index child The second client 104 can derive the private key of the second user according to the following formula, and further, the second client 104 can generate: SK child codechild =Hash 512 (SK parent ∥code parent ∥index child (1)

[0083] The derived private key can use an algorithm based on BIP32. In practice, the parent private key SK can be used first. parent Parent chain code parent The index number of the sub-user. child The keys are concatenated, and then a hash operation is performed on the concatenated result, such as a hash512 operation. In this example, the private key can be 256 bits, and the chaincode can be 256 bits.

[0084] Then, the second client 104 can generate the second user's public key based on the second user's private key. The second user's public key can be a sub-public key, denoted as PK. parent The second client 104 can generate the second user's public key using the following formula:

[0085] in, This indicates the dot product operation of elliptic curves, where "G" represents the base point.

[0086] Next, the second client 104 can derive the second user's identity certificate based on the second user's private key, the second user's public key, and the second derived information (the second user's derived information). This derived information, denoted as a message, represents the hierarchical relationship between users and is typically formed by accumulating user identifiers. When generating a sub-user, the sub-user's user identifier (such as an index) can be added to the message to obtain the sub-user's message. The sub-user's message can be stored in the extended field of the identity certificate, allowing upper-level users to deduce the sub-user's private key based on their own private key and the aforementioned message.

[0087] In this example, the second user is a sub-user, and the second user's identity certificate can be denoted as Cert. child It can be based on the sub-private key SK child Public key PK child Sub-user derived information messages identity For details on generation, please refer to the following formula: Cert child =Sign(SK child PK child ∥message identyity (3)

[0088] The derived identity certificate can be obtained by splicing (or connecting) the child public key and the derived information of the child user, and then signing the child private key and the splicing result.

[0089] Based on this, the second client 104 can extract the public key of the second user from the identity certificate of the second user.

[0090] S404, the second client 104 uses the public key of the second user to encrypt the data layer by layer to obtain ciphertext.

[0091] The public key of the second user is generated based on the derived hierarchical encryption algorithm, based on which the second client 104 can use the public key of the second user to encrypt the data through the hierarchical encryption algorithm, thereby obtaining the ciphertext.

[0092] S406, the second client 104 stores the ciphertext and the identity certificate of the second user to the blockchain network 200.

[0093] Specifically, the second client 104 can attach the identity certificate of the second user to the ciphertext, for example, after the ciphertext. Then the second client 104 performs a chain operation on the ciphertext, thereby storing the ciphertext with the identity certificate of the second user attached to the blockchain network 200. In some examples, the second client 104 can also perform a chain operation on the ciphertext and the identity certificate of the second user respectively, thereby storing the ciphertext and the identity certificate of the second user to the blockchain network 200.

[0094] S408, the first client 102 obtains the ciphertext and the identity certificate of the second user from the blockchain network 200.

[0095] The first client 102 can perform an on-chain read operation to obtain the ciphertext and the identity certificate of the second user from the blockchain network 200. Specifically, the first client 102 can read the ciphertext and the identity certificate of the second user from the ledger maintained by the chain node.

[0096] S410, the first client 102 verifies the legality of the identity certificate of the second user using the root certificate.

[0097] Specifically, the identity certificate of the second user is derived based on the root certificate, based on which the first client 102 can use the root certificate to verify the legality of the identity certificate of the second user. The root certificate can include a root public key and a root private key, the root public key can be publicly announced, and the first client 102 can verify whether the identity certificate is tampered according to the fingerprint of the identity certificate.

[0098] Specifically, before the identity certificate is issued, the CA can determine a hash value of the issued identity certificate using the root private key through a fingerprint algorithm, which usually needs to be decrypted by the corresponding root public key. In the verification of the identity certificate, the first client 102 can use the same fingerprint algorithm to calculate another hash value of the identity certificate of the second user. If the hash value determined by the first client 102 based on the fingerprint algorithm is the same as the hash value parsed from the signature on the identity certificate, it means that the identity certificate has not been tampered with, and the identity certificate passes the legality verification. If the hash value determined based on the fingerprint algorithm is not the same as the hash value parsed from the signature on the identity certificate, it means that the identity certificate has been tampered with, and the identity certificate fails the legality verification.

[0099] S412、the first client 102 extracts the first derived information from the identity certificate of the first user, and extracts the second derived information from the identity certificate of the second user.

[0100] The first derived information is used to indicate the derivation path of the identity certificate of the first user, and the second derived information is used to indicate the derivation path of the identity certificate of the second user. The derivation path can be accumulated by user identification, such as index number. Based on this, the first derived information can include the user identification of the first user and the user identification of the upper user of the first user, and the second derived information can include the user identification of the second user and the user identification of the upper user of the second user. Wherein, the user identification can be recorded in sequence in the form of an array, or recorded in sequence in the form of a directory, to indicate the derivation level.

[0101] For the convenience of understanding, an example is described below. In this example, the user identification of the first user is "id1", and the user identification of the second user is "id2".

[0102] For the second user with index "id2", the second derived information can be represented as: message: "derive_path":["id1","id2"].

[0103] The user identification in the array is recorded in sequence, specifically according to the derivation relationship (derivation level relationship), based on which it can be determined that the first user is the upper user of the second user.

[0104] For the second user with index "id2", the second derived information can also be represented as: message: "derive_path":" / id1 / id2".

[0105] The user identification in the directory is recorded according to the derivation relationship or the derivation level relationship, based on which it can be determined that the first user is the upper user of the second user.

[0106] In some possible implementation, the derived information can be attached in the extension field of the identity certificate, based on which the first client 102 can read the first derived information from the extension field of the identity certificate of the first user, for example, read the derived path of the identity certificate of the first user. Similarly, the first client 102 can read the second derived information from the extension field of the identity certificate of the second user, for example, read the derived path of the identity certificate of the second user.

[0107] S414, the first client 102 determines the private key of the second user according to the first derived information, the second derived information and the private key of the first user.

[0108] Specifically, the first client 102 can determine the hierarchical relationship between the first user and the second user according to the first derived information and the second derived information. For example, the first client 102 can compare the first derived information and the second derived information, when the length of the second derived information is greater than the length of the first derived information, and the second derived information includes the first derived information, it can be determined that the first user is the upper user of the second user. The first client 102 can extract the user identifier of the second user from the second derived information according to the hierarchical relationship. For example, when it is determined that the first user is the upper user of the second user, the first client 102 can extract the identifier of the second user from the second derived information. Considering that the second derived information can be generated according to the first derived information and the user identifier of the second user, the first client 102 can compare the second derived information and the first derived information, and determine the difference information as the user identifier of the second user. Then the first client 102 can determine the private key of the second user through the derivation algorithm according to the private key of the first user and the identifier of the second user. Wherein, the determination of the private key of the second user through the derivation algorithm according to the private key of the first user and the identifier of the second user can refer to the related content described in the above formula (1), which will not be repeated here. It should be noted that when the first user is not the direct superior user of the second user, but the indirect superior user, the first client 102 can extract the user identifier (index) of different users layer by layer to derive the private key of the lower user.

[0109] In some possible implementation, the first client 102 splices the private key of the first user and the chain code of the first user, the user identifier of the second user to obtain a splicing result, and then the first client 102 performs hash operation on the splicing result to obtain the private key of the second user.

[0110] In some possible implementation manners, the first client 102 determines the private key of the third user according to the private key of the first user and the user identifier of the third user, wherein the third user is a child user of the first user. Then the first client 102 can determine the private key of the second user according to the private key of the third user and the user identifier of the second user, wherein the second user is a child user of the third user.

[0111] S416, the first client 102 decrypts the ciphertext according to the private key of the second user to obtain the data.

[0112] Since the ciphertext is obtained by encrypting the data of the plaintext using the public key of the second user derived based on the hierarchical encryption algorithm, the second client 102 can use the private key of the second user to decrypt the ciphertext in combination with the hierarchical encryption algorithm to obtain the data of the plaintext.

[0113] Based on the foregoing description, the present application provides a data processing method. The method combines the private key and the identity certificate used for transaction signature and verification of the transaction signature in the blockchain network with the hierarchical encryption, carries the derived information in the extension field of the identity certificate, specifically the user hierarchical relationship, so that the identity certificate not only has the function of transaction signature and verification of the signature, but also has the function of hierarchical encryption and decryption. Moreover, the method can use the root private key to verify the legality of the identity certificate, without introducing a trusted third party to solve the authenticity and validity of the public key, thereby avoiding the introduction of the centralized risk, reducing the cost, and meeting the business demand.

[0114] Based on the foregoing data processing method, the present application further provides a blockchain management system 10. The blockchain management system 10 of the present application is introduced from the perspective of functional modularization as follows.

[0115] Referring to a schematic structural diagram of a blockchain management system 10 shown in FIG. 2, the blockchain management system 10 includes a first client 102, a second client 104, and a blockchain network 200. The first client 102 is a client of a first user, and the second client 104 is a client of a second user.

[0116] The second client 104 is configured to extract the public key of the second user from the identity certificate of the second user, use the public key of the second user to perform hierarchical encryption on data to obtain ciphertext, and store the ciphertext and the identity certificate of the second user to the blockchain network.

[0117] The first client 102 is configured to obtain the ciphertext and the identity certificate of the second user from the blockchain network, and verify the legality of the identity certificate of the second user using a root certificate.

[0118] The first client 102 is further configured to extract first derived information from the identity certificate of the first user and second derived information from the identity certificate of the second user when the verification is passed, wherein the first derived information is used to indicate a derivation path of the identity certificate of the first user, and the second derived information is used to indicate a derivation path of the identity certificate of the second user.

[0119] The first client 102 is further configured to determine the private key of the second user according to the first derived information, the second derived information and the private key of the first user.

[0120] The first client 102 is further configured to decrypt the ciphertext according to the private key of the second user to obtain the data.

[0121] The first client 102 and the second client 104 can be client software or client hardware. In addition, the blockchain nodes 202 in the blockchain network 200 can refer to software for forming the blockchain network 200, or hardware.

[0122] When implemented by software, the first client 102 and the second client 104 can be an application program running on a computing device. The application program can be a dedicated client or a browser. The above-mentioned application program can also be virtualized to provide a virtualized service to users. The virtualized service can include a virtual machine (VM) service, a bare metal server (BMS) service or a container service. The VM service can be a service that provides a VM for users to use on demand by virtualizing a VM resource pool on multiple physical hosts through a virtualization technology. The BMS service is a service that provides a BMS for users to use on demand by virtualizing a BMS resource pool on multiple physical hosts. The container service is a service that provides a container for users to use on demand by virtualizing a container resource pool on multiple physical hosts. The VM is a virtual computer simulated, i.e. a logical computer. The BMS is a high-performance computing service that can be scaled elastically, and its computing performance is no different from that of a traditional physical machine, and it has the feature of secure physical isolation. The container is a kernel virtualization technology that can provide lightweight virtualization to achieve the purpose of isolating user space, processes and resources. It should be understood that the VM service, the BMS service and the container service in the above-mentioned virtualized service are only specific examples, and in actual applications, the virtualized service can also be other lightweight or heavyweight virtualized services, which are not limited here.

[0123] When implemented by hardware, the first client 102 and the second client 104 can include at least one computing device. For example, the first client 102 can be a terminal of a first user, and the second client 104 can be a terminal of a second user. Alternatively, the first client 102 and the second client 104 can also be devices implemented by an application-specific integrated circuit (ASIC) or a programmable logic device (PLD), and the like. The PLD can be implemented by a complex programmable logical device (CPLD), a field-programmable gate array (FPGA), a generic array logic (GAL), or any combination thereof.

[0124] In some possible implementation manners, the first client 102 is specifically configured to:

[0125] determine a hierarchical relationship between the first user and the second user according to the first derived information and the second derived information;

[0126] extract a user identifier of the second user from the second derived information according to the hierarchical relationship;

[0127] determine a private key of the second user by a derivation algorithm according to the user identifier of the second user and the private key of the first user.

[0128] In some possible implementation manners, the first client 102 is specifically configured to:

[0129] concatenate the private key of the first user and chain code of the first user and the user identifier of the second user to obtain a concatenation result;

[0130] perform a hash operation on the concatenation result to obtain the private key of the second user.

[0131] In some possible implementation manners, the first client 102 is specifically configured to:

[0132] determine a private key of a third user by a derivation algorithm according to the private key of the first user and a user identifier of the third user, the third user being a child user of the first user;

[0133] determine a private key of a second user by a derivation algorithm according to the private key of the third user and a user identifier of the second user, the second user being a child user of the third user.

[0134] In some possible implementation manners, the second derived information is generated according to the first derived information and a user identifier of the second user.

[0135] In some possible implementation manners, the first client 102 is specifically configured to:

[0136] extracting first derived information from an extension field of the identity certificate of the first user.

[0137] The application further provides a computing device 500. As shown in FIG. 5, the computing device 500 includes a bus 502, a processor 504, a memory 506, and a communication interface 508. The processor 504, the memory 506, and the communication interface 508 communicate with each other through the bus 502. The computing device 500 can be a server or a terminal device. It should be understood that the number of processors and memories in the computing device 500 is not limited in the application.

[0138] The bus 502 can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, only one line is used in FIG. 5, but it does not mean that there is only one bus or only one type of bus. The bus 502 can include a path for transmitting information between various components (for example, the memory 506, the processor 504, the communication interface 508) of the computing device 500.

[0139] The processor 504 can include any one or more of a central processing unit (CPU), a graphics processing unit (GPU), a microprocessor (MP), or a digital signal processor (DSP), etc.

[0140] The memory 506 can include volatile memory, such as random access memory (RAM), and non-volatile memory, such as read-only memory (ROM), flash memory, a hard disk drive (HDD), or a solid-state drive (SSD). The memory 506 stores executable program code that is executed by the processor 504 to implement the aforementioned data processing method. Specifically, the memory 506 stores instructions for the blockchain management system 200 to implement the data processing method. For example, the memory 506 stores instructions for implementing the functions of the first client 102, the second client 104, and / or the blockchain node 202. It should be noted that in some cases, one computing device 500 can execute instructions for implementing the functions of the first client 102 in one data processing process, and execute instructions for implementing the functions of the second client 104 in another data processing process.

[0141] The communication interface 508 uses a transceiving module such as, but not limited to, a network interface card or a transceiver to enable communication between the computing device 500 and other devices or communication networks.

[0142] Embodiments of the present application also provide a computing device cluster. The computing device cluster includes at least one computing device. The computing device can be a server, such as a central server, an edge server, or a local server in a local data center. In some embodiments, the computing device can also be a terminal device such as a desktop computer, a laptop computer, or a smartphone.

[0143] As shown in FIG. 6, the computing device cluster includes at least one computing device 500. The memory 506 in one or more computing devices 500 in the computing device cluster can store the same instructions for the blockchain management system 200 to implement the data processing method.

[0144] In some possible implementations, one or more computing devices 500 in the computing device cluster can also be used to execute part of the instructions for the blockchain management system 200 to implement the data processing method. In other words, a combination of one or more computing devices 500 can collectively execute the instructions for the blockchain management system 200 to implement the data processing method.

[0145] It should be noted that the memory 506 in different computing devices 500 in the computing device cluster can store different instructions for implementing part of the functions of the blockchain management system 200.

[0146] Figure 7 illustrates one possible implementation. As shown in Figure 7, one or more computing devices in the cluster of computing devices can be connected through a network. Among others, the network can be a wide area network or a local area network, etc. For example, computing device 500A, computing device 500B, and computing device 500C, computing device 500D, computing device 500E are connected through the network. Specifically, each computing device can be connected to the network through a respective communication interface. In this type of possible implementation, the memory 506 in the computing device 500A stores instructions for performing the functions of the first client 102, and the memory 506 in the computing device 500B stores instructions for performing the functions of the second client 104. Meanwhile, the memory 506 in the computing device 500C, the computing device 500D, and the computing device 500E stores instructions for performing the functions of the blockchain node 202.

[0147] The connection between the cluster of computing devices shown in Figure 7 can be that the data processing method provided in the present application requires a large amount of resources for encryption and decryption, key generation, on-chain storage, and therefore the functions of the first client 102, the second client 104, and the blockchain node 202 are implemented by independent computing devices, for example, the functions of the first client 102 are implemented by the computing device 500A, the functions of the second client 104 are implemented by the computing device 500B, and the functions of the blockchain node 202 are implemented by the computing device 500C, the computing device 500D, and the computing device 500E. It should be noted that Figure 7 illustrates the case where the blockchain network 200 includes three blockchain nodes 202, and in actual applications, the blockchain network 200 can include more than three blockchain nodes 202.

[0148] It should be understood that the functions of the computing device 500A shown in Figure 7 can also be completed by multiple computing devices 500. Similarly, the functions of the computing device 500B can also be completed by multiple computing devices 500, and the functions of the computing device 500C, 500D, and 500E can also be completed by multiple computing devices.

[0149] The embodiments of the present application also provide a computer-readable storage medium. The computer-readable storage medium can be any available medium or data storage device that can be accessed by a computing device, such as a data center containing one or more available media. The available media can be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state disk), etc. The computer-readable storage medium includes instructions that instruct the computing device to perform the above-mentioned data processing method applied to the blockchain management system 200.

[0150] The embodiments of the present application further provide a computer program product containing instructions. The computer program product can be a software or program product containing instructions, which can run on a computing device or be stored in any available medium. When the computer program product runs on at least one computing device, the at least one computing device is caused to perform the above data processing method.

[0151] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the protection scope of the technical solutions of the embodiments of the present application.

Claims

1. A data processing method, characterized in that, Applied to a blockchain management system, the blockchain management system includes a first client, a second client, and a blockchain network, wherein the first client is a client of a first user, and the second client is a client of a second user, the method includes: The second client extracts the second user's public key from the second user's identity certificate, uses the second user's public key to encrypt the data in layers to obtain ciphertext, and stores the ciphertext and the second user's identity certificate in the blockchain network; The first client obtains the ciphertext and the second user's identity certificate from the blockchain network, and uses the root certificate to verify the legitimacy of the second user's identity certificate; When the verification is successful, the first client extracts first derived information from the first user's identity certificate and second derived information from the second user's identity certificate. The first derived information is used to indicate the derivation path of the first user's identity certificate, and the second derived information is used to indicate the derivation path of the second user's identity certificate. The first client determines the second user's private key based on the first derived information, the second derived information, and the first user's private key; The first client decrypts the ciphertext using the second user's private key to obtain the data.

2. The method according to claim 1, characterized in that, The first client determines the second user's private key based on the first derived information, the second derived information, and the first user's private key, including: The first client determines the hierarchical relationship between the first user and the second user based on the first derived information and the second derived information; The first client extracts the user identifier of the second user from the second derived information according to the hierarchical relationship; The first client determines the second user's private key using a derivation algorithm based on the second user's user identifier and the first user's private key.

3. The method according to claim 2, characterized in that, The first client determines the second user's private key using a derivation algorithm based on the second user's user identifier and the first user's private key, including: The first client concatenates the first user's private key, the first user's chaincode, and the second user's user identifier to obtain the concatenation result; The first client performs a hash operation on the concatenated result to obtain the private key of the second user.

4. The method according to claim 2, characterized in that, The first client determines the second user's private key using a derivation algorithm based on the second user's user identifier and the first user's private key, including: The first client determines the private key of the third user based on the private key of the first user and the user identifier of the third user through a derivation algorithm. The third user is a sub-user of the first user. The first client determines the private key of the second user based on the private key of the third user and the user identifier of the second user through a derivation algorithm. The second user is a sub-user of the third user.

5. The method according to any one of claims 1 to 4, characterized in that, The second derived information is generated based on the first derived information and the user identifier of the second user.

6. The method according to any one of claims 1 to 5, characterized in that, The first client extracts first derived information from the first user's identity certificate, including: The first client extracts the first derived information from the extended fields of the first user's identity certificate.

7. A blockchain management system, characterized in that, The blockchain management system includes a first client, a second client, and a blockchain network. The first client is the client of a first user, and the second client is the client of a second user. The second client is used to extract the public key of the second user from the identity certificate of the second user, use the public key of the second user to encrypt the data in layers to obtain ciphertext, and store the ciphertext and the identity certificate of the second user in the blockchain network; The first client is configured to obtain the ciphertext and the identity certificate of the second user from the blockchain network, and verify the legitimacy of the identity certificate of the second user using the root certificate; The first client is further configured to, upon successful verification, extract first derived information from the first user's identity certificate and second derived information from the second user's identity certificate, wherein the first derived information is used to indicate the derivation path of the first user's identity certificate and the second derived information is used to indicate the derivation path of the second user's identity certificate. The first client is further configured to determine the private key of the second user based on the first derived information, the second derived information, and the private key of the first user; The first client is also configured to decrypt the ciphertext using the second user's private key to obtain the data.

8. The system according to claim 7, characterized in that, The first client is specifically used for: Based on the first derived information and the second derived information, determine the hierarchical relationship between the first user and the second user; Based on the hierarchical relationship, extract the user identifier of the second user from the second derived information; The private key of the second user is determined by a derivation algorithm based on the user identifier of the second user and the private key of the first user.

9. The system according to claim 8, characterized in that, The first client is specifically used for: The private key of the first user, the chaincode of the first user, and the user identifier of the second user are concatenated to obtain the concatenation result; Perform a hash operation on the concatenated result to obtain the private key of the second user.

10. The system according to claim 8, characterized in that, The first client is specifically used for: Based on the private key of the first user and the user identifier of the third user, the private key of the third user is determined by a derivation algorithm, and the third user is a sub-user of the first user; Based on the private key of the third user and the user identifier of the second user, the private key of the second user is determined by a derivation algorithm, and the second user is a sub-user of the third user.

11. The system according to any one of claims 7 to 10, characterized in that, The second derived information is generated based on the first derived information and the user identifier of the second user.

12. The system according to any one of claims 7 to 11, characterized in that, The first client is specifically used for: Extract the first derived information from the extended fields of the first user's identity certificate.

13. A computing device cluster, characterized in that, The computing device cluster includes at least one computing device, the at least one computing device including at least one processor and at least one memory, the at least one memory storing computer-readable instructions; the at least one processor executes the computer-readable instructions to cause the computing device cluster to perform the data processing method as described in any one of claims 1 to 6.

14. A computer-readable storage medium, characterized in that, Includes computer-readable instructions; the computer-readable instructions are used to implement the data processing method according to any one of claims 1 to 6.

15. A computer program product, characterized in that, Includes computer-readable instructions; the computer-readable instructions are used to implement the data processing method according to any one of claims 1 to 6.

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