WO2021184885A1

WO2021184885A1 - Method and device for use in updating public key set at blockchain node

Info

Publication number: WO2021184885A1
Application number: PCT/CN2020/139905
Authority: WO
Inventors: 林鹏
Original assignee: 支付宝(杭州)信息技术有限公司
Priority date: 2020-03-16
Filing date: 2020-12-28
Publication date: 2021-09-23
Also published as: CN111047324A; CN111047324B

Abstract

Provided is a method for use in updating a public key set at a blockchain node, the public key set comprising public keys of all blockchain nodes participating in a consensus in a blockchain network. The method comprises: with respect to at least one newly added block, determining, on the basis of receipt index information and a node change-type transaction identifier in a block header of the block, whether a node change-type transaction indicated by the node change-type transaction identifier is present in the block (402), the receipt information comprising a transaction type identifier field; when the node change-type transaction is present in the block, acquiring block body information of the block (404); acquiring receipt information of the node change-type transaction in the block body information (406), the receipt information comprising a public key field, the public key field being used for storing a public key of a changed blockchain node indicated by the node change-type transaction; acquiring the public key of the changed blockchain node from the public key field of the receipt information (408); and utilizing the acquired public key to update a public key set (410).

Description

Method and device for updating public key set at block chain node

Technical field

The embodiments of this specification relate to blockchain technology, and in particular, to a method and device for updating a public key set at a blockchain node.

Background technique

In the blockchain system, due to the needs of certain blockchain operations, the public key set of all blockchain nodes in the blockchain system may be maintained at each blockchain node. In the blockchain system, it is inevitable that blockchain node changes will occur, for example, a new blockchain node joins the blockchain system or a joined blockchain node exits the blockchain system. When the blockchain node changes, a trusted way is needed to update the public key set in the blockchain system.

Summary of the invention

In view of the above, the embodiments of this specification provide a method and device for updating the public key set at a blockchain node.

According to one aspect of the embodiments of this specification, a method for updating a public key set at a blockchain node is provided, the public key set includes the public key set of all blockchain nodes participating in consensus in the blockchain network. The method includes: for at least one newly added block, based on the receipt index information and the node change transaction identifier in the block header of the block, determining whether the node change transaction identifier exists in the block The indicated node change type transaction, the node change type transaction uses the smart contract used to perform the blockchain node change operation as the transaction object, the receipt index information includes a transaction type identification field, and the transaction type identification field indicates the area The transaction type of each transaction in the block; when there is a node change transaction in the block, obtain the block body information of the block; obtain the receipt information of the node change transaction from the block body information, The receipt information includes a public key field, and the public key field is used to store the public key of the changed blockchain node indicated by the node change transaction; the changed public key field is obtained from the public key field of the receipt information The public key of the blockchain node; and using the obtained public key to update the set of public keys.

Optionally, in an example, the block body information may include a transaction tree and a receipt tree, and obtaining the receipt information of the node change transaction from the block body information may include: based on the node change type Transaction identifier, which determines the address of the designated initiator designated to initiate the node change transaction and the smart contract address corresponding to the node change transaction; based on the transaction tree information in the block body information and the designated initiator address And the smart contract address, determining the node change transaction and the first position of the node change transaction in the transaction tree from the transaction tree; and obtaining and determined from the receipt tree The receipt information at the second location corresponding to the first location of.

Optionally, in an example, before obtaining the receipt information at the second position corresponding to the determined first position in the receipt tree, obtain the node change transaction from the block body information The receipt information of may further include: verifying the node change transaction based on the transaction object address included in the node change transaction and the smart contract address of the smart contract. Obtaining the receipt information at the second position corresponding to the determined first position in the receipt tree includes: when the node change transaction verification is passed, obtaining the receipt information corresponding to the determined first position in the receipt tree The receipt information at the second location.

Optionally, in an example, based on the transaction object address information of the node change transaction determined from the transaction tree and the smart contract address of the smart contract, verifying the node change transaction may include: Based on the transaction initiator address, the transaction object address, the designated initiator address and the smart contract address of the node change transaction determined from the transaction tree, the node change transaction found is verified.

Optionally, in an example, the node change transaction identifier indicates that the node adds a new transaction, and using the obtained public key to update the public key set may include: adding the public key to the public key In the set, or the node change transaction identifier instructs the node to delete the transaction, using the obtained public key to update the public key set includes: deleting the public key from the public key set.

Optionally, in an example, the blockchain system may be a consortium chain system.

Optionally, in an example, the smart contract may be deployed in the genesis block.

According to another aspect of the embodiments of this specification, there is also a device for updating a set of public keys in a consortium chain, where the set of public keys includes the public keys of all blockchain nodes participating in the consensus in the blockchain network, so The device includes: a node change transaction determining unit, for at least one newly added block, based on the receipt index information in the block header of the block and the node change transaction identifier, determine whether the node change type exists in the block A node change type transaction indicated by a transaction identifier, the node change type transaction uses a smart contract for performing a blockchain node change operation as a transaction object, the receipt index information includes a transaction type identification field, and the transaction type identification field Indicate the transaction type of each transaction in the block; the block body information obtaining unit, when there is a node change transaction in the block, obtain the block body information of the block; the receipt information obtaining unit, from the block Obtain the receipt information of the node change transaction in the block information, the receipt information includes a public key field, and the public key field is used to store the public key of the changed blockchain node indicated by the node change transaction A public key acquisition unit that acquires the public key of the changed blockchain node from the public key field of the receipt information; and a public key set update unit that uses the acquired public key to update the public key set.

Optionally, in an example, the block body information may include a transaction tree and a receipt tree, and the receipt information acquisition unit may include: a designated transaction information determining module, which determines that the designated transaction information is designated based on the node change transaction identifier The address of the designated initiator that initiates the node change transaction and the smart contract address corresponding to the node change transaction; the first location determination module is based on the transaction tree information in the block body information and the address of the designated initiator And the smart contract address, which determines the node change type transaction and the first position of the node change type transaction in the transaction tree from the transaction tree; and a receipt information acquisition module from the receipt tree To obtain the receipt information at the second location corresponding to the determined first location.

Optionally, in an example, the receipt information obtaining unit may include: a node change transaction verification module, before obtaining the receipt information at the second position corresponding to the determined first position in the receipt tree , Verifying the node change transaction based on the transaction object address contained in the node change transaction and the smart contract address of the smart contract, and the receipt information acquisition module when the node change transaction is verified To obtain the receipt information at the second location corresponding to the determined first location in the receipt tree.

Optionally, in an example, the node change transaction verification module may be based on the transaction initiator address, the transaction object address, the designated initiator address, and the node change transaction determined from the transaction tree. The smart contract address verifies the node change transaction found.

Optionally, in an example, the node change transaction identifier may indicate that the node adds a new transaction, and the public key set update unit may add the public key to the public key set, or the node The change transaction identifier may instruct the node to delete the transaction, and the public key set update unit may delete the public key from the public key set.

According to another aspect of the embodiments of this specification, there is also provided a computing device, including: at least one processor; and a memory, the memory stores instructions, and when the instructions are executed by the at least one processor, the At least one processor executes the method as described above.

According to another aspect of the embodiments of the present specification, there is also provided a non-transitory machine-readable storage medium, which stores executable instructions, which when executed cause the machine to execute the method as described above.

Using the method and device of the embodiment of this specification, the block body is obtained when it is determined that there is a node change transaction indicated by the node change transaction identifier in the corresponding block based on the receipt index information in the block header and the node change transaction identifier. Information, and then obtain the public key of the blockchain node corresponding to the node change exchange based on the obtained block body information, and then use the obtained public key to update the public key set, which can not only provide a trusted block The chain public key set update method, and because the block body information acquisition and public key acquisition process are executed after determining that there is a node change transaction, it can reduce the burden on each blockchain node.

Description of the drawings

By referring to the following drawings, a further understanding of the nature and advantages of the contents of the embodiments of this specification can be achieved. In the drawings, similar components or features may have the same reference signs. The accompanying drawings are used to provide a further understanding of the embodiments of the present invention, and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the embodiments of the specification, but do not constitute an example of the embodiments of the specification. limit. In the attached picture:

FIG. 1 shows a schematic diagram of an example of an environment that can be used to execute a method for updating a public key set at a blockchain node according to an embodiment of the present specification;

FIG. 2 shows a schematic diagram of an example of a system architecture that executes the method for updating a public key set at a blockchain node according to an embodiment of the present specification;

FIG. 3 shows a schematic diagram of an example of a blockchain system to which the method for updating a public key set at a blockchain node according to an embodiment of the present specification is applicable;

Fig. 4 is a flowchart of a method for updating a public key set at a blockchain node according to an embodiment of the present specification;

5 is a flowchart of an example of the receipt information acquisition process in the method for updating the public key set at the blockchain node according to an embodiment of the present specification;

6 is a flowchart of another example of the receipt information acquisition process in the method for updating a public key set at a blockchain node according to an embodiment of the present specification;

Fig. 7 is a structural block diagram of an apparatus for updating a public key set at a blockchain node according to an embodiment of the present specification;

FIG. 8 is a structural block diagram of the receipt information obtaining unit in the device for updating the public key set at the blockchain node shown in FIG. 7; and

Fig. 9 is a structural block diagram of a computing device for implementing a method for updating a public key set at a blockchain node according to an embodiment of the present specification.

Detailed ways

The subject described herein will be discussed below with reference to example embodiments. It should be understood that the discussion of these embodiments is only to enable those skilled in the art to better understand and realize the subject described herein, and is not to limit the scope of protection, applicability, or examples set forth in the claims. The function and arrangement of the discussed elements can be changed without departing from the protection scope of the content of the embodiments of this specification. Various examples can omit, substitute, or add various procedures or components as needed. In addition, features described with respect to some examples can also be combined in other examples.

As used herein, the term "including" and its variations mean open terms, meaning "including but not limited to". The term "based on" means "based at least in part on." The terms "one embodiment" and "an embodiment" mean "at least one embodiment." The term "another embodiment" means "at least one other embodiment." The terms "first", "second", etc. may refer to different or the same objects. Other definitions can be included below, whether explicit or implicit. Unless clearly indicated in the context, the definition of a term is consistent throughout the specification.

In this document, the term "connected" refers to direct mechanical connection, communication or electrical connection between two components, or indirect mechanical connection, communication or electrical connection through intermediate components. The term "electrically connected" refers to the possibility of electrical communication between two components for data/information exchange. Similarly, the electrical connection may refer to a direct electrical connection between two components, or an indirect electrical connection through an intermediate component. The electrical connection can be implemented in a wired manner or a wireless manner.

Now, the method and device for updating the public key set at the blockchain node according to the embodiments of the present specification will be described with reference to the accompanying drawings.

Blockchain is a chain data structure that connects and combines data blocks sequentially in chronological order, and cryptographically ensures that the data blocks cannot be tampered with or forged. The blockchain includes one or more blocks. Each block in the blockchain is linked to the previous block by including the encrypted hash of the immediately preceding block in the blockchain. Each block also includes a timestamp, a cryptographic hash of the block, and one or more transactions. The transaction that has been verified by the blockchain node is hashed and a Merkle tree is formed. In the Merkle tree, the data at the leaf nodes is hashed, and for each branch of the Merkle tree, all the hash values of the branch are concatenated at the root of the branch. The above processing is performed on the Merkle tree until the root node of the entire Merkle tree. The root node of the Merkle tree stores hash values representing all data in the Merkle tree. When a hash value claims to be a transaction stored in the Merkle tree, it can be quickly verified by judging whether the hash value is consistent with the structure of the Merkle tree.

Blockchain is a data structure used to store transactions. The blockchain network is a network of computing nodes used to manage, update and maintain one or more blockchain structures. As mentioned above, the blockchain network can include a public blockchain network, a private blockchain network, or a consortium blockchain network.

In the public blockchain network, the consensus process is controlled by the nodes of the consensus network. For example, there may be thousands of entities in a public blockchain network for collaborative processing, and each entity operates at least one node in the public blockchain network. Therefore, the public blockchain network can be considered as a public network of participating entities. In some examples, most entities (nodes) must sign each block in sequence, and add the signed block to the blockchain of the blockchain network. Examples of public blockchain networks may include specific peer-to-peer payment networks. In addition, the term "blockchain" does not specifically refer to any particular blockchain.

The public blockchain network supports public transactions. Public transactions are shared among all nodes in the public blockchain network and stored in the global blockchain. A global blockchain refers to a blockchain that is replicated across all nodes. In order to reach a consensus (for example, agree to add a block to the blockchain), a consensus agreement is implemented in the public blockchain network. Examples of consensus protocols include but are not limited to: proof-of-work (POW), proof-of-stake (POS), and proof-of-authority (POA). In the embodiments of this specification, POW is used as a non-limiting example.

Private blockchain networks are provided for specific entities. The read and write permissions of each node in the private blockchain network are strictly controlled. Therefore, a private blockchain network is usually also called a permissioned network, which restricts who is allowed to participate in the network and the level of network participation (for example, only in certain transaction situations). In a private blockchain network, various types of access control mechanisms can be used (for example, existing participants vote to add new entities, regulatory agencies control permissions, etc.).

The alliance blockchain network is private among participating entities. In the alliance blockchain network, the consensus process is controlled by authorized nodes. For example, a consortium composed of several (for example, 10) entities (for example, financial institutions, insurance companies) can operate a consortium blockchain network, and each entity operates at least one node in the consortium blockchain network. Therefore, the consortium blockchain network can be considered as a private network of participating entities. In some examples, each participating entity (node) must sign each block in sequence and add the block to the blockchain. In some examples, each block may be signed by a subset of participating entities (nodes) (for example, at least 7 entities), and the block may be added to the blockchain.

Blockchain is a tamper-proof shared digital ledger that records transactions in a public or private peer-to-peer network. The ledger is distributed to all member nodes in the network, and the history of asset transactions that occurred in the network is permanently recorded in the block.

The consensus mechanism ensures that all network nodes in the distributed blockchain network execute transactions in the same order and then write to the same ledger.

FIG. 1 shows a schematic diagram of an example of an environment 100 that can be used to execute a method for updating a public key set at a blockchain node according to an embodiment of the present specification. In some examples, the environment 100 enables entities to participate in the blockchain network 102. As shown in FIG. 1, the environment 100 includes a network 104, and computing devices/

systems

106, 108. In some examples, the network 104 may include a local area network (LAN), a wide area network (WAN), the Internet, or a combination thereof, and connect a website, a user device (eg, a computing device), and a back-end system. In some examples, the network 104 may be accessed through a wired and/or wireless communication link. In some examples, the computing devices/

systems

106 and 108 communicate with each other through the network 104, and communicate with the blockchain network 102 through the network 104, and the nodes (or node devices) in the blockchain network 102 pass through The network 104 communicates. Generally, the network 104 represents one or more communication networks. In some cases, the computing devices/

systems

106, 108 may be nodes of a cloud computing system (not shown), or each computing device/

system

106, 108 may be a separate cloud computing system, including interconnection through the network 104 Multiple computers and used as a distributed processing system.

In the illustrated example, each of the computing devices/

systems

106, 108 may include any suitable computing system capable of participating as a node in the blockchain network 102. Examples of computing devices/systems include, but are not limited to, servers, desktop computers, laptops, tablet devices, smart phones, etc. In some examples, one or more computer-implemented services for interacting with the blockchain network 102 may be installed on the computing device/

system

106, 108. For example, the computing device/system 106 may be installed with the services of the first entity (for example, user A), for example, the first entity is used to manage transactions with one or more other entities (for example, other users). Management system. The computing device/system 108 may be installed with services of a second entity (for example, user B), for example, a transaction management system used by the second entity to manage transactions with one or more other entities (for example, other users) . In the example of FIG. 1, the blockchain network 102 is represented as a peer-to-peer network of nodes, and the computing devices/

systems

106, 108 serve as the nodes of the first entity and the second entity participating in the blockchain network 102, respectively.

FIG. 2 shows a schematic diagram of an example of a system architecture 200 that executes the method for updating a public key set at a blockchain node according to an embodiment of the present specification. An example of the system architecture 200 includes the

participant systems

202, 204, and 206 corresponding to the participant A, the participant B, and the participant C, respectively. Each participant (eg, user, enterprise) participates in the blockchain network 212 provided as a peer-to-peer network. The blockchain network 212 includes a plurality of nodes 214, wherein at least some of the nodes 214 record information in the blockchain 216, and the recorded information cannot be changed. Although a single blockchain 216 is schematically shown within the blockchain network 212, multiple copies of the blockchain 216 may be provided, and multiple copies are maintained in the blockchain network 212, as described in detail later of.

In the example shown, each

participant system

202, 204, 206 is provided by participant A, participant B, and participant C, or provided as participant A, participant B, and participant C, respectively, And it serves as the corresponding node 214 in the blockchain network 212. As used herein, a node generally refers to a single system (eg, computer, server) connected to the blockchain network 212 and enables corresponding participants to participate in the blockchain network. In the example shown in FIG. 2, the participant corresponds to each node 214. However, one participant can operate multiple nodes 214 within the blockchain network 212, and/or multiple participants can share a single node 214. In some examples, the

participant systems

202, 204, 206 use protocols (e.g., Hypertext Transfer Protocol Security (HTTPS)) and/or use remote procedure calls (RPC) to communicate with the blockchain network 212, or through the blockchain The chain network 212 communicates.

The degree of participation of the node 214 in the blockchain network 212 may vary. For example, some nodes 214 may participate in the consensus process (eg, as miner nodes that add blocks to the blockchain 216), while other nodes 214 do not participate in the consensus process. As another example, some nodes 214 store a complete copy of the blockchain 216, while other nodes 214 only store a partial copy of the blockchain 216. In the example of Figure 2, the

participant systems

202, 204, 206 each store a complete copy of the blockchain 216 216', 216", 216"'.

A blockchain (for example, the blockchain 216 in FIG. 2) is composed of a series of blocks, and each block stores data. Examples of data may include transaction data representing transactions between two or more participants. In the embodiments of this specification, transactions are used as a non-limiting example, and it is expected that any appropriate data can be stored in the blockchain (for example, documents, images, videos, audios). Examples of transactions may include, but are not limited to, the exchange of valuable things (for example, assets, products, services, currency, etc.). Transaction data is stored immutably in the blockchain.

Before storing in the block, hash the transaction data. Hashing is the process of converting transaction data (provided as string data) into a fixed-length hash value (also provided as string data). After the transaction data is hashed, even a slight change in the transaction data will result in a completely different hash value. The hash value is usually generated by hashing transaction data using a hash function. Examples of hash functions include, but are not limited to, Secure Hash Algorithm (SHA)-256, which outputs a 256-bit hash value.

The transaction data of multiple transactions can be stored in the block after being hashed. For example, two transaction data are hashed to obtain two hash values, and then the two obtained hash values are hashed again to obtain another hash value. This process is repeated until a single hash value is obtained for all transactions to be stored in the block. This hash value is called the Merkle root hash and is stored at the head of the block. Any change in the transaction will cause its hash value to change, and eventually the Merkle root hash value will change.

The block is added to the blockchain through a consensus protocol. Multiple nodes in the blockchain network participate in the consensus protocol and add blocks to the blockchain after competition. Such nodes are called miner nodes (or accounting nodes). The POW introduced above serves as a non-limiting example.

Miner nodes perform a consensus process to add transactions (corresponding blocks) to the blockchain. Although multiple miner nodes participate in the consensus process, only one miner node can write a block to the blockchain. In other words, miner nodes compete in the consensus process to add their blocks to the blockchain. In more detail, the miner node periodically collects pending transactions from the transaction pool (for example, until a predetermined limit on the number of transactions that can be included in the block is reached, if any). The transaction pool includes transaction messages from participants in the blockchain network. Miner nodes create blocks and add transactions to the blocks. Before adding the transaction to the block, the miner node checks whether there is a transaction in the block of the blockchain among the transactions to be added. If the transaction has been added to another block, the transaction will be discarded.

The miner node generates a block header, hashes all transactions in the block, and combines the hash values in pairs to generate further hash values until a single hash value (Merkle root) is obtained for all transactions in the block. Hash). Then, add the Merkle root hash to the block header. The miner also determines the hash value of the latest block in the blockchain (ie, the last block added to the blockchain). Miner nodes can also add random values (noune values) and timestamps to the block header. During the mining process, the miner node tries to find a hash value that meets the required parameters. The miner node keeps changing the nonce value until it finds a hash value that meets the required parameters.

Every miner in the blockchain network tries to find a hash value that meets the required parameters and competes with each other in this way. Finally, a miner node finds a hash value that meets the required parameters and advertises the hash value to all other miner nodes in the blockchain network. Other miner nodes verify the hash value, and if it is determined to be correct, verify each transaction in the block, accept the block, and attach the block to their copy of the blockchain. In this way, the global state of the blockchain is agreed upon on all miner nodes within the blockchain network. The above process is a POW consensus protocol.

In the example provided in Figure 2, participant A wants to send a certain amount of funds to participant B. Participant A generates a transaction message and sends the transaction message to the blockchain network, and the transaction message is added to the transaction pool. Each miner node in the blockchain network creates a block, obtains transactions from the transaction pool, and adds the transaction to the block. In this way, the transaction issued by participant A is added to the block of the miner node.

In some blockchain networks, cryptography is implemented to maintain the privacy of transactions. For example, if two nodes want to maintain the privacy of the transaction so that other nodes in the blockchain network cannot learn the details of the transaction, the node can encrypt the transaction data. Examples of encryption methods include, but are not limited to, symmetric encryption and asymmetric encryption. Symmetric encryption refers to the encryption process that uses a single key to encrypt (generate ciphertext based on plaintext) and decrypt (generate plaintext based on ciphertext). In symmetric encryption, multiple nodes can use the same key, so each node can encrypt/decrypt transaction data.

In asymmetric encryption, a key pair is used for encryption and decryption, and each key pair includes a different private key and public key. For a node, the private key in its asymmetric encryption key pair needs to be stored confidentially; the public key can be made public for other nodes to obtain. If the data is encrypted with a public key, only the corresponding private key can be used to decrypt it. For example, refer to Figure 1 again. Participant A can use the public key of participant B to encrypt data, and send the encrypted data to participant B. Participant B can use its private key to decrypt the encrypted data (ciphertext) sent from participant A and decrypt the original data (plaintext). Messages encrypted with the public key of the node can only be decrypted with the corresponding private key in the paired secret key.

Asymmetric encryption can also be used to provide digital signatures, which enable participants in a transaction to confirm other participants in the transaction and the validity of the transaction. For example, participant A can digitally sign the message, and another participant B can confirm that the message was sent by the participant A according to the digital signature of the participant A. Digital signatures can also be used to ensure that messages are not tampered with during transmission. For example, refer to Figure 1 again. Participant A will send a message to participant B. Participant A generates a hash value of the message, and then uses its private key to encrypt the hash value to generate a digital signature. Participant A attaches the digital signature to the message, and sends the message with the digital signature to participant B. Participant B uses the public key of participant A to decrypt the digital signature, thereby decrypting the corresponding hash value. Participant B hashes the received message to obtain another hash value, and then compares the two hash values. If the hash value is the same, participant B can confirm that the message is indeed from participant A and has not been tampered with.

In the embodiment of this specification, the blockchain node can be any participant in FIG. 1 or FIG. 2.

FIG. 3 shows a schematic diagram of an example of a blockchain system to which the method for updating a public key set at a blockchain node according to an embodiment of the present specification is applicable.

As shown in FIG. 3, the blockchain system 300 includes lightweight nodes and full nodes. The full nodes include

blockchain nodes

301, 302, etc., and the lightweight nodes are connected to one or more full nodes. For example, the

blockchain nodes

301a, 301b, and 301c, which are lightweight nodes, are connected to the full node 301, and the blockchain nodes 302a, 302b, and 302c are connected to the full node 302. Each full node in the blockchain system 300 is connected to each other, and each full node can be used as an accounting node to jointly maintain a ledger of all transactions in the blockchain system based on the blockchain technology. The accounting node can perform accounting operations such as transaction verification, transaction consensus, and block generation. Full nodes usually maintain all the data of the blockchain locally, including the block body and block header of each block in the blockchain. Lightweight nodes can only store the block headers of each block in the blockchain locally for simple verification operations (for example, SPV verification). Lightweight nodes can always be connected to the same full number of nodes, and can also replace all connected nodes based on connection rules to reduce trust risks.

The transactions initiated by each blockchain node can be broadcast to the blockchain network for consensus processing (for example, consensus processing can be performed based on the PoW mechanism). The transaction initiated by the full node can be broadcast to each other full node, and after each full node receives the transaction, it can be broadcast to the lightweight node it is connected to. The transaction initiated by the light-weight node can be sent to all nodes connected to the light-weight node, so as to be broadcast by the all-weight node to other full-weight nodes or light-weight nodes.

The method implemented in this specification for updating the public key set at a blockchain node can be executed by the accounting node, or can be executed by the light node. The public key set in this specification includes the public keys of all blockchain nodes participating in the consensus (the accounting node shown in Figure 3) in the blockchain network. The method for updating the public key set at the node of the blockchain in the following embodiments can be used in the consortium chain, and can also be used in the public chain.

Fig. 4 is a flowchart of a method for updating a public key set at a blockchain node according to an embodiment of the present specification.

As shown in FIG. 4, in block 402, for at least one newly added block, based on the receipt index information and the node change transaction identifier in the block header of the block, it is determined whether there is a node change transaction identifier in the block. The indicated node change transaction.

For the accounting node, the newly added block can be a newly generated block in the blockchain. The accounting node can monitor the newly generated block to determine whether a node change transaction has occurred in the blockchain system. The accounting node can also periodically scan the block headers of new blocks that have not been scanned, and determine in a timely manner whether a node change transaction has occurred. For lightweight nodes, the newly added block can be a block newly downloaded by the lightweight node from the full node. Lightweight nodes can download block headers from full nodes in any manner. For example, they can download a predetermined number of block headers every predetermined period, or they can download locally missing block headers in a predetermined period. After downloading the block header, the lightweight node can scan each newly downloaded block header at a suitable time period to determine whether there is a node change transaction in each block header.

The node change transaction takes the smart contract used to execute the blockchain node change operation as the transaction object. Smart contracts used to perform blockchain node change operations can be deployed in the genesis block of the blockchain. Node change transactions can be initiated by a designated transaction initiator. The designated transaction initiator can be, for example, an administrator in a blockchain system, and the administrator can be a server composed of one or more computing devices. The node change transaction can be a node addition transaction or a node deletion transaction. Correspondingly, the smart contract may include adding a smart contract to a node and deleting a smart contract to a node. When a new blockchain node requests to join the blockchain network, the administrator can initiate a new node type transaction with the node new smart contract as the transaction object. When it is necessary to delete a blockchain node from the blockchain network, the administrator can initiate a node deletion transaction with the node deletion smart contract as the transaction object.

The receipt index information includes a transaction type identification field, and the transaction type identification field indicates the transaction type of each transaction in the block. The block body of each block may include receipt information of each transaction on the block, and each transaction receipt information may be stored in the block in the form of a receipt tree (for example, a receipt tree generated based on a Merck tree). The receipt information of each transaction may include the transaction type (Topic) corresponding to the transaction. The transaction type may include, for example, a transfer transaction, a node change transaction, a smart contract addition or deletion transaction, and the like. When the accounting node packages each transaction to generate a block, it can generate receipt index information based on the transaction type in the receipt information of each transaction in the block, and include the receipt index information in the block header. In one example, the transaction type identification corresponding to each transaction may be included in the receipt index information. The receipt index information may be a Bloom filter, for example. When determining whether there is a node change transaction in a block, the receipt index information can be found based on the node change transaction identifier. When the node change transaction identifier exists in the receipt index information, it can be determined that there is a node change transaction in the block. . The node change type transaction identifier may be a node new type transaction identifier indicating a node new type transaction, or a node deletion type transaction identifier of a node deletion type transaction.

When there is a node change transaction in the block, in block 404, block body information of the block is obtained. Due to the large amount of block body information, if there is no node change transaction in the block, there is no need to obtain block body information, which can reduce the burden on blockchain nodes. When the blockchain node is a lightweight node, due to the limited computing resources and local storage space of the lightweight node, obtaining block body information after determining that there is a node change transaction is more suitable for the operation requirements of the lightweight node.

After the block body information is obtained, in block 406, the receipt information of the node change transaction is obtained from the block body information. The receipt information includes a public key field, which is used to store the public key of the changed blockchain node indicated by the node change transaction. As an example, when a billing node processes a node change transaction, it can write the public key of the blockchain node corresponding to the node change transaction in the public key field. If the transaction is not a node change transaction, the accounting node may not write any information to the public key field, that is, the public key field is empty. In another example, when the transaction is a node change transaction, the accounting node can make the receipt information of the transaction include the public key field, and for transactions that are not node change transactions, the receipt information of the transaction can be made not include the public key field. Key field.

As an example, the data structure of the receipt information may be TransactionReceipt<result,gasUsed,logEntries,output>, where TransactionReceipt represents the receipt, result is the execution result of the smart contract, gasused is the gas consumed to execute the smart contract, and output is the public key. Field, logEntries executes the log entry of the corresponding transaction, and the transaction log information can be included in the log entry. In another example, the public key field may also be included in the log information.

An exemplary process of obtaining receipt information will be described below with reference to FIG. 5.

After the receipt information is obtained, in block 408, the public key of the changed blockchain node is obtained from the public key field of the receipt information. The changed blockchain node can be a newly added blockchain node or a deleted blockchain node. The receipt information in the receipt information may be information after encoding. In this case, the receipt information may be decoded by a decoding method corresponding to the encoding method. For example, the encoding method may be RLP encoding, and the RLP decoding method may be used for decoding during decoding. After obtaining the decoded receipt information, the public key of the changed blockchain node can be obtained from it.

After the public key is obtained, in block 410, the public key set is updated with the obtained public key. When the node change transaction identifier instructs the node to add a new transaction, the obtained public key can be added to the public key set. If the node change transaction identifier instructs the node to delete the transaction, the obtained public key can be deleted from the public key set.

Through this embodiment, a trusted public key set update method can be provided, and the public key set update process can fully adapt to the resource constraints of lightweight nodes, so it can provide a public key set update that is more friendly to lightweight nodes. method.

Fig. 5 is a flowchart of an example of a receipt information acquisition process in a method for updating a public key set at a blockchain node according to an embodiment of the present specification. In this example, the acquired block body information includes a transaction tree and a receipt tree.

As shown in FIG. 5, at block 502, based on the node change transaction identifier, the designated initiator address of the designated node change transaction and the smart contract address corresponding to the node change transaction are determined. In an example, the designated initiators of the node deletion transaction and the node addition transaction may be the same, for example, both may be administrators. In another example, different designated initiators may be determined for node deletion transactions and node addition transactions, respectively.

When it is determined that there is a node change transaction in the block based on the receipt index information in the block header, the designated initiator and the corresponding smart contract address can be determined based on the specific type of the existing node change transaction. The address of the designated initiator and the corresponding smart contract address of various node change transactions can be stored at the local blockchain node. When it is determined that there is a node change transaction, the designated initiator address and smart contract address can be read according to the node change transaction type indicated by the corresponding node change transaction. For example, if the node change transaction is a node addition transaction, the address of the designated initiator of the node addition transaction and the corresponding smart contract address can be read.

Then, in block 504, based on the transaction tree information in the block body information and the designated initiator address and smart contract address, the node change transaction and the first position of the node change transaction in the transaction tree are determined from the transaction tree. The determined designated initiator address and smart contract address can be compared with the transaction address of each transaction in the transaction tree to determine that the initiator address matches the designated initiator address and the transaction corresponding address is consistent with the determined smart contract Transactions with matching addresses. The transaction thus determined is the corresponding node change transaction, and the position of the transaction in the transaction tree is the first position of the node change transaction in the transaction tree.

After the first location is determined, at block 506, the receipt information at the second location corresponding to the determined first location is obtained from the receipt tree. The position of each transaction in the transaction tree corresponds to the position of the receipt information of the transaction in the receipt tree. For example, when the accounting node packs each transaction into a block, it can generate the transaction tree and the receipt tree in the same order. Thus, the position of the receipt information of each transaction in the receipt tree is the same as the position of the transaction information of the transaction in the transaction tree, so that after determining the position of the node change transaction in the transaction pair, the same position of the receipt tree can be determined. To get the receipt information. For example, if the node change transaction is located at the first leaf node in the transaction tree, the receipt information located at the first leaf node in the receipt tree can be obtained to obtain the determined receipt information of the node change transaction.

After the receipt information is obtained, the corresponding public key can be obtained from the public key field of the obtained receipt information. If the receipt information is encoded information, the corresponding decoding method can be used to decode it to obtain the public key of the changed node.

In another example, in order to improve the reliability of the determined node change transaction, you can refer to FIG. 6, before obtaining the receipt information at the second position corresponding to the determined first position in the receipt tree, The determined node change transaction is verified to determine whether the determined node change transaction is indeed a node change transaction. Fig. 6 is a flowchart of another example of a receipt information acquisition process in a method for updating a public key set at a blockchain node according to an embodiment of the present specification.

As shown in Figure 6, at block 602, a node change transaction is determined from the transaction tree

In block 604 and, based on the transaction object address contained in the node change transaction and the smart contract address of the smart contract, the node change transaction is verified, and in block 606, it is determined whether the node change transaction passes the verification. For example, the transaction object address and smart contract address of the node change transaction determined from the transaction tree can be hashed, and then the hash values of the two can be compared whether they are consistent. When the hash values of the two are the same, it indicates that the node change type transaction that is traded from the transaction tree is indeed the node change type transaction to be found.

In an example, the address of the transaction initiator and the address of the transaction object of the node change transaction determined from the transaction tree can be verified separately. The transaction initiator address verification can be performed based on the transaction initiator address of the node change transaction determined from the transaction tree and the designated initiator address of the corresponding node change transaction, and based on the node change transaction determined from the transaction tree The address of the transaction object and the address of the smart contract are used to verify the address of the transaction object for the found node change transaction. As an example, the transaction initiator address and transaction object address, designated initiator address and smart contract address of the node change transaction determined from the transaction tree can be hashed separately, and then the hash values can be compared to see if they are consistent. Perform transaction initiator address verification and transaction corresponding address verification. When the address of the transaction initiator is consistent with the address of the designated initiator and the address of the transaction object is consistent with the address of the smart contract, it can be determined that the node change type transaction determined from the transaction tree has passed the verification.

When the verification of the node change transaction determined from the transaction tree is passed, in block 608, the receipt information at the second location corresponding to the determined first location in the receipt tree is obtained. As a result, it is possible to avoid unnecessary waste of computing resources due to errors in the determined node change transaction type.

Fig. 7 is a structural block diagram of an apparatus for updating a public key set at a blockchain node according to an embodiment of the present specification. As shown in FIG. 7, the public key set update device 700 includes a node change transaction determination unit 710, a block body information acquisition unit 720, a receipt information acquisition unit 730, a public key acquisition unit 740, and a public key set update unit.

For at least one newly added block, the node change transaction determining unit 710 determines whether there is a node indicated by the node change transaction identifier in the block based on the receipt index information in the block header of the block and the node change transaction identifier Change transaction. The node change transaction takes the smart contract used to execute the blockchain node change operation as the transaction object. The receipt index information includes a transaction type identification field, and the transaction type identification field indicates the transaction type of each transaction in the block. When there is a node change transaction in the block, the block body information obtaining unit 720 obtains the block body information of the block. After obtaining the block body information, the receipt information obtaining unit 730 obtains the receipt information of the node change transaction from the block body information. The receipt information includes a public key field, and the public key field is used to store the public key of the changed blockchain node indicated by the node change transaction. The public key obtaining unit 740 obtains the public key of the changed blockchain node from the public key field of the receipt information.

When the public key is acquired, the public key set update unit 750 uses the acquired public key to update the public key set. In an example, the node change type transaction identifier may indicate the node new type transaction. At this time, the public key set update unit 750 may add the public key to the public key set. In another example, the node change transaction identifier may also instruct the node to delete the transaction. At this time, the public key set update unit 750 may delete the public key from the public key set.

FIG. 8 is a structural block diagram of the receipt information obtaining unit 730 in the apparatus for updating the public key set at the blockchain node shown in FIG. 7. As shown in FIG. 8, the receipt information acquisition unit 730 includes a designated transaction information determination module 731, a first location determination module 732, a node change transaction verification module 733, a receipt information acquisition module 734, and a receipt information acquisition module 735. In this example, the block body information includes a transaction tree and a receipt tree.

The designated transaction information determining module 731 determines the designated initiator address of the designated initiating node change transaction and the smart contract address corresponding to the node change transaction based on the node change transaction identifier. The first location determination module 732 determines the node change transaction and the node change transaction in the transaction tree from the transaction tree based on the transaction tree information in the block body information, the designated initiator address, and the smart contract address. The first position.

After determining the first location, the node change transaction verification module 733 verifies the node change transaction based on the transaction object address included in the node change transaction and the smart contract address of the smart contract. In another example, the node change transaction verification module 733 can determine the node change transaction based on the transaction initiator address, transaction object address, designated initiator address, and smart contract address of the node change transaction determined from the transaction tree. Change the transaction for verification.

When the node change transaction is verified, the receipt information obtaining module 734 obtains the receipt information at the second location corresponding to the determined first location in the receipt tree.

In another example, the node change transaction verification module may not be included. In this example, after the first position determination module 732 determines the node change transaction and its first position in the transaction tree from the transaction tree, the receipt information acquisition module 734 may obtain the receipt from the receipt based on the determined first position. Obtain the corresponding receipt information from the tree.

With reference to FIGS. 1 to 8 above, the embodiments of the method and device for updating the public key set at a blockchain node according to the embodiments of the present specification have been described. The details mentioned in the above description of the method embodiment are also applicable to the embodiment of the device in the embodiment of this specification.

The device for updating the public key set at the blockchain node in the embodiment of this specification can be implemented by hardware, or by software or a combination of hardware and software. The various embodiments in this specification are described in a progressive manner, and the same or similar parts among the various embodiments are referred to each other.

The device for updating the public key set at the blockchain node in the embodiment of this specification can be implemented by hardware, or by software or a combination of hardware and software. Taking software implementation as an example, as a logical device, it is formed by reading the corresponding computer program instructions in the memory into the memory through the processor of the device where it is located. In the embodiment of the present specification, the device for updating the public key set at the blockchain node can be implemented by using a computing device, for example.

Fig. 9 is a structural block diagram of a computing device for implementing a method for updating a public key set at a blockchain node according to an embodiment of the present specification. As shown in FIG. 9, the computing device 900 includes a processor 910, a memory 920, a memory 930, a communication interface 940, and an internal bus 950, and the processor 910, a memory (for example, a non-volatile memory) 920, a memory 930, and a communication interface 940 are connected together via a bus 950. According to an embodiment, the computing device 900 may include at least one processor 910 that executes at least one computer-readable instruction (ie, the aforementioned Elements implemented in software).

In one embodiment, computer-executable instructions are stored in the memory 920, which when executed, cause at least one processor 910 to: for at least one newly added block, based on the receipt index information and the node in the block header of the block Change transaction identifier to determine whether there is a node change transaction indicated by the node change transaction identifier in the block; when there is a node change transaction in the block, obtain the block body information of the block; Obtain the receipt information of the node change transaction from the block body information. The receipt information includes a public key field. The public key field is used to store the public key of the changed blockchain node indicated by the node change transaction; from the public key of the receipt information Obtain the public key of the changed blockchain node in the field; and use the obtained public key to update the public key set.

It should be understood that the computer-executable instructions stored in the memory 920, when executed, cause at least one processor 910 to perform the various operations and functions described above in conjunction with FIGS. 1-8 in the various embodiments of the embodiments of this specification.

According to one embodiment, a program product such as a non-transitory machine-readable medium is provided. The non-transitory machine-readable medium may have instructions (that is, the above-mentioned elements implemented in the form of software), which when executed by a machine, cause the machine to execute the above described in conjunction with FIGS. 1-8 in the various embodiments of the embodiments of this specification. Various operations and functions.

Specifically, a system or device equipped with a readable storage medium may be provided, and the software program code for realizing the function of any one of the above-mentioned embodiments is stored on the readable storage medium, and the computer or device of the system or device The processor reads and executes the instructions stored in the readable storage medium.

In this case, the program code itself read from the readable medium can implement the function of any one of the above embodiments, so the machine readable code and the readable storage medium storing the machine readable code constitute the present invention a part of.

Examples of readable storage media include floppy disks, hard disks, magneto-optical disks, optical disks (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD-RW), magnetic tape, Volatile memory card and ROM. Alternatively, the program code can be downloaded from the server computer or the cloud via the communication network.

The foregoing describes specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps described in the claims can be performed in a different order than in the embodiments and still achieve desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or sequential order shown in order to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

Not all steps and units in the above processes and system structure diagrams are necessary, and some steps or units can be omitted according to actual needs. The order of execution of each step is not fixed and can be determined as needed. The device structure described in the foregoing embodiments may be a physical structure or a logical structure, that is, some units may be implemented by the same physical entity, or some units may be implemented by multiple physical entities, or may be implemented by multiple physical entities. Some components in independent devices are implemented together.

The term "exemplary" used throughout this specification means "serving as an example, instance, or illustration", and does not mean "preferred" or "advantageous" over other embodiments. The detailed description includes specific details for the purpose of providing an understanding of the described technology. However, these techniques can be implemented without these specific details. In some instances, in order to avoid incomprehensibility to the concepts of the described embodiments, well-known structures and devices are shown in the form of block diagrams.

The above describes in detail the optional implementation manners of the embodiments of the embodiments of this specification with reference to the accompanying drawings. However, the embodiments of the embodiments of this specification are not limited to the specific details in the above-mentioned embodiments. Within the scope of the conception, a variety of simple modifications can be made to the technical solutions of the embodiments of the embodiments of the present specification, and these simple modifications all belong to the protection scope of the embodiments of the embodiments of the present specification.

The foregoing description of the content of the embodiments of this specification is provided to enable any person of ordinary skill in the art to implement or use the content of the embodiments of this specification. It is obvious to a person of ordinary skill in the art that various modifications made to the content of the embodiments of this specification are obvious, and the general principles defined herein can also be used without departing from the scope of protection of the content of the embodiments of this specification. Apply to other variants. Therefore, the contents of the embodiments of this specification are not limited to the examples and designs described herein, but are consistent with the widest scope that conforms to the principles and novel features disclosed herein.

Claims

A method for updating a public key set at a blockchain node, the public key set including the public keys of all blockchain nodes participating in consensus in a blockchain network, and the method includes:

For at least one newly added block, based on the receipt index information and the node change transaction identifier in the block header of the block, determine whether the node change transaction indicated by the node change transaction identifier exists in the block, and The node change type transaction uses a smart contract for performing the block chain node change operation as the transaction object, the receipt index information includes a transaction type identification field, and the transaction type identification field indicates the transaction of each transaction in the block type;

When there is a node change transaction in the block, obtain the block body information of the block;

Obtain the receipt information of the node change transaction from the block body information, the receipt information includes a public key field, and the public key field is used to store the changed blockchain indicated by the node change transaction The public key of the node;

The public key of the changed blockchain node obtained from the public key field of the receipt information; and

Use the obtained public key to update the set of public keys.
The method of claim 1, wherein the block body information includes a transaction tree and a receipt tree, and obtaining the receipt information of the node change transaction from the block body information includes:

Based on the node change transaction identifier, determine the address of the designated initiator designated to initiate the node change transaction and the smart contract address corresponding to the node change transaction;

Based on the transaction tree information in the block body information, the designated initiator address and the smart contract address, it is determined from the transaction tree that the node change transaction and the node change transaction are in the The first position in the transaction tree; and

The receipt information at the second location corresponding to the determined first location is obtained from the receipt tree.
The method of claim 2, wherein before obtaining the receipt information at the second position corresponding to the determined first position in the receipt tree, the node change is obtained from the block body information The receipt information for such transactions also includes:

Verifying the node change transaction based on the transaction object address included in the node change transaction and the smart contract address of the smart contract,

Obtaining the receipt information at the second location corresponding to the determined first location in the receipt tree includes:

When the verification of the node change transaction is passed, the receipt information at the second location corresponding to the determined first location in the receipt tree is obtained.
The method of claim 3, wherein, based on the transaction object address information of the node change transaction determined from the transaction tree and the smart contract address of the smart contract, verifying the node change transaction comprises :

Based on the transaction initiator address, the transaction object address, the designated initiator address, and the smart contract address of the node change transaction determined from the transaction tree, the node change transaction found is verified.
The method according to any one of claims 1 to 4, wherein the node change transaction identifier instructs the node to add a new transaction, and using the obtained public key to update the public key set comprises:

Add the public key to the set of public keys, or

The node change transaction identifier instructs the node to delete the transaction, and using the obtained public key to update the public key set includes:

The public key is deleted from the public key set.
The method according to any one of claims 1-4, wherein the blockchain system is a consortium chain system.
The method according to any one of claims 1 to 4, wherein the smart contract is deployed in the genesis block.
A device for updating a set of public keys in a consortium chain, the set of public keys includes the public keys of all blockchain nodes participating in consensus in a blockchain network, and the device includes:

The node change transaction determining unit, for at least one newly added block, based on the receipt index information and the node change transaction identifier in the block header of the block, determines whether there is a node change transaction identifier in the block indicated by the node change transaction identifier The node change type transaction, the node change type transaction uses the smart contract used to perform the block chain node change operation as the transaction object, the receipt index information includes a transaction type identification field, and the transaction type identification field indicates the block The transaction type of each transaction in;

The block body information obtaining unit, when there is a node change transaction in the block, obtain the block body information of the block;

A receipt information obtaining unit, which obtains the receipt information of the node change transaction from the block body information, the receipt information includes a public key field, and the public key field is used to store information instructed by the node change transaction The public key of the changed blockchain node;

The public key obtaining unit obtains the public key of the changed blockchain node from the public key field of the receipt information; and

The public key set update unit uses the obtained public key to update the public key set.
8. The device of claim 8, wherein the block body information includes a transaction tree and a receipt tree, and the receipt information obtaining unit includes:

The designated transaction information determining module determines, based on the node change transaction identifier, the address of the designated initiator designated to initiate the node change transaction and the smart contract address corresponding to the node change transaction;

The first location determination module determines the node change transaction and the node from the transaction tree based on the transaction tree information in the block body information, the designated initiator address, and the smart contract address The first position of the change transaction in the transaction tree; and

The receipt information obtaining module obtains the receipt information at the second location corresponding to the determined first location from the receipt tree.
8. The apparatus according to claim 8, wherein the receipt information obtaining unit comprises:

The node change transaction verification module, before obtaining the receipt information at the second position corresponding to the determined first position in the receipt tree, is based on the transaction object address and the intelligence contained in the node change transaction The smart contract address of the contract verifies the node change transaction, and

The receipt information obtaining module obtains the receipt information at the second location corresponding to the determined first location in the receipt tree when the node change transaction verification is passed.
The device according to claim 10, wherein the node change transaction verification module is based on the transaction initiator address, the transaction object address, the designated initiator address, and the address of the node change transaction determined from the transaction tree. The smart contract address is used to verify the found node change transaction.
The device according to any one of claims 8-11, wherein the node change transaction identifier indicates that the node adds a new transaction, and the public key set update unit adds the public key to the public key set ,or

The node change transaction identifier instructs the node to delete the transaction, and the public key set update unit deletes the public key from the public key set.
A computing device including:

At least one processor; and

A memory, where the memory stores instructions, and when the instructions are executed by the at least one processor, the at least one processor executes the method according to any one of claims 1 to 7.
A machine-readable storage medium storing executable instructions, which when executed, cause the machine to execute the method according to any one of claims 1 to 7.