73 results about "Aggregate signature" patented technology

Various aspects of the subject technology relate to systems, methods, and machine-readable media for cross-chain communication in a blockchain platform. Various aspects may include accepting, at a first blockchain, a first transaction including a message and a message payload. Aspects may also include validating, at the first blockchain, the message by signing the message using signature keys of one or more validators in a first set of validators of the first blockchain. Aspects may also include generating an aggregate signature based on the signature keys of the one or more validators in a first set of validators. Aspects may also include submitting a second transaction on to a second blockchain, the second transaction including the message and the aggregate signature. Aspects may include validating, at the second blockchain, the second transaction based on a shared registry.

A method and system for generating and verifying a monotone policy aggregate signature σf a message. The method involves storing a common message at a local storage device, generating a signature for the common message using a secret cryptographic key at a local signature generation module, and transmitting the user signature to an aggregator module. The aggregator module combines the user signature with other user signatures to generate an aggregate signature. The aggregate signature is then transmitted to a verification module for verification. The monotone policy aggregate signatures are constructed from non-interactive batch arguments that support adaptive subset extraction for expressive monotone policies.

The invention relates to a decentralized identifier-based on-chain digital identity privacy protection scheme, which specifically comprises the following steps of: selectively revealing declaration based on a BLS signature and a Merkle hash tree for a low privacy scene: replacing a declaration set structure with the hash tree by a publisher, and aggregating the signature by a user; according to the selective disclosure declaration based on BBS + signature for a high privacy scene, a publisher can blindly sign a user certificate, and a user can realize zero-knowledge proof so as to hide attributes; according to the extension layer design based on the universal parser, original direct interaction between the universal parser and a decentralized account book is converted into indirect interaction to process DID document data. The method has the advantage of high time overhead in a low-privacy-degree scene, a certain balance between privacy and time overhead is achieved in a high-privacy-degree scene, meanwhile, privacy during DID document analysis is enhanced, and the association problem in the DID analysis process is relieved.

A system for enabling escrow-free, secure, and convenient atomic asset swaps between blockchains are provided. In detail, when any group of users reach an agreement on the content of cross-chain asset swap transactions, each participant creates an individual signature on the content of each transaction, employs a reversible signature aggregate function to produce an aggregate signature from all his / her individual signatures, and optionally generates a proof to prove the relationship between the aggregated signature and the transaction contents. Sequentially, all the participants exchange these aggregated signatures and optional proofs. Once a participant publishes one of his / her individual signature, the other parties can use both signatures—one from the sender and the other from the recipient—to construct a complete transaction. Once a transaction is broadcast, its corresponding transactions are constructed, and broadcast. Upon all transactions being confirmed by the blockchain nodes or miners, the asset swap between participants is completed.

A data processing method includes: transmitting, by a first service node, service data information to a second service node, so that the second service node obtains data signature information; a first key parameter and a second key parameter that are both related to a random parameter; the random parameter being determined by the second service node based on a node private key and the service data information; performing signature verification on the received data signature information based on the first key parameter and the second key parameter, and adding a signature verification result obtained after signature verification to a verification result set; searching for a target signature verification result that satisfies a valid verification condition from the verification result set; and performing aggregate signature on the data signature information obtained after calculation when a quantity of signatures of the target signature verification result satisfies an aggregate signature condition.

The invention provides a lightweight consensus method suitable for a large-scale unmanned aerial vehicle cluster. The lightweight consensus method comprises the steps that a master unmanned aerial vehicle generates a proposal according to a client instruction and a qualification proof and sends the proposal to a slave unmanned aerial vehicle; verifying the legality of the proposal and the qualification proof from the unmanned aerial vehicle, signing the proposal according to the private key fragment and the commitment list after the verification is passed, and generating a signature fragment and a new commitment; the slave unmanned aerial vehicle sends the signature fragment and the new commitment as a proposed vote to the master unmanned aerial vehicle; and after the main unmanned aerial vehicle receives a target number of votes passing verification, aggregating a plurality of signature fragments to obtain an aggregated signature, and generating a qualification proof of a next round of proposal by using the aggregated signature and the new commitment list, thereby completing a round of voting, and realizing consensus of a client instruction after three rounds of voting. According to the method, the calculation amount, the storage amount and the communication complexity can be reduced, and the lightweight of the block chain system is realized in calculation, storage and communication, so that the transaction processing delay is reduced, and the system throughput is improved.

The invention relates to a bank-enterprise direct connection scene-oriented revocable security signcryption method, and belongs to the field of information security. According to the method, digital signature and encryption are deeply coupled in a single logic step, so that the calculation complexity is reduced, and the requirements of confidentiality, integrity and non-repudiation of information transmission in a financial scene are met; and meanwhile, a key updating mechanism is designed, so that access blocking of the history and the newly-added ciphertext after permission revocation is ensured. In order to solve a subversive attack possibly initiated by an internal opponent, a password reverse firewall architecture is introduced, an encrypted ciphertext is reconstructed through a re-randomization module, and algorithm risks possibly caused by tampering of a random number generator are blocked. A block chain intelligent contract and aggregation signature technology is further introduced, a fair and reliable decentralized verification platform supporting batch verification is constructed for bank and enterprise users, the cloud verification efficiency is improved, and responsibility tracing can be performed through records on the block chain when major property safety accidents occur.

The invention discloses a smart tea garden block chain traceability system and method, and the method comprises the following steps: carrying out the standardization processing and aggregation of data of each link, and generating an event set identifier; performing compact commitment on the event set by adopting an RSA accumulator to generate a staged commitment value; introducing a BLS threshold signature mechanism, and performing joint signature on the event set by a plurality of trusted nodes to generate an aggregation signature; binding and writing the commitment value and the aggregation signature into a block chain; in traceability query, the existence of events is verified through an RSA accumulator, and node consensus is verified through a BLS threshold signature, so that a safe, transparent and verifiable traceability system is constructed. The system covers the whole process information management of tea from planting, processing, storage, transportation to sales.

The invention discloses a security time-limited verifiable and traceable threshold signature method and system. The security time-limited verifiable and traceable threshold signature system comprises a plurality of signer modules, an aggregator module, a tracker module and a notarist module, wherein the signer module signs data to obtain signature fragments, constructs a time lock puzzle and a commitment, processes the data and correspondingly sends the data to an aggregator, a tracker and a notarization person; after receiving the data, the aggregator module processes the data to obtain an aggregation signature, constructs a proof and a commitment, and sends the data to the tracker module; after receiving the data, the tracker module applies for a token, decrypts the data by using the token, and tracks the data to obtain a signer sequence after verification is passed; and after receiving the application, the notarist module gives a token, and if the aggregator does not perform correct aggregation within the specified time, the notarist processes related data and recovers an aggregation signature. According to the method, the privacy and the traceability of the threshold signature are considered while the security time limit can be verified and traced.

The invention provides an anti-collusion attack VANET privacy protection method based on certificateless aggregation signature, and relates to the technical field of vehicle-mounted network security. The method specifically comprises the following steps: constructing an anti-collusion attack VANET privacy protection model based on certificateless aggregation signature, wherein the anti-collusion attack VANET privacy protection model comprises a vehicle provided with a vehicle-mounted unit, a roadside unit, an application server, a key generation center and a trusted mechanism; wherein the roadside unit is mainly used for aggregating signatures of vehicles and transmitting the signatures to the application server; the application server is mainly used for verifying the validity of the aggregation signature, detecting whether the VANET is subjected to a collusion attack, and sending the invalid aggregation signature which does not pass the verification to the trusted mechanism; the key generation center is mainly used for generating part of private keys for the vehicle; and the trusted mechanism is mainly used for providing registration service for the roadside unit and the vehicle and generating a pseudonym for the vehicle so as to reveal the true identity of the illegal signature from the application server by using the pseudonym of the vehicle.

A signature control method implemented by a computer, the signature control method including: acquiring, by a processor circuit of the computer, a plurality of pieces of document information and signature information that corresponds to each piece of document information of the plurality of pieces of document information; generating, by the processor circuit of the computer, aggregate signature information obtained by aggregating the signature information that corresponds to the each piece of document information of the plurality of acquired pieces of document information on a basis of the plurality of acquired pieces of document information; and outputting, by the processor circuit of the computer, the generated aggregate signature information in association with aggregate public key information obtained by aggregating public key information that corresponds to the each piece of document information of the plurality of pieces of document information and the plurality of pieces of document information.

The invention relates to an efficient and extensible inter-group data ownership transfer method. Comprising the following steps: 1) generating a group user key; 2) generating a data integrity auditing label; 3) auditing data integrity; 4) dynamically joining or quitting the group users; and 5) data ownership transfer. According to the method, a random mask is added to a private key indexed in an integrity auditing label, and meanwhile public parameters corresponding to the random mask are calculated. Compared with the problem that the existing scheme is difficult to adapt to the dynamic characteristics of the group, the method has the advantages that 1) the structure of the BLS aggregation signature is adaptively optimized, the rogue key attack can be effectively resisted, and the ownership of the group to the data can be transferred only under the condition that the public key and the private key are consistent; the generated data integrity auditing label can effectively resist collusion attacks, safety of sensitive information such as private keys of two transaction parties is guaranteed, participation of any trusted third party is not needed, and the method is more suitable for actual production.

To provide a communication system capable of minimizing an amount of signature data.SOLUTION: When a signature system is a one-to-one signature system, each of the terminal devices 5 to 7 transmits a data msg detected by itself, identification information id of itself, a signature system type, and the tag tag generated by signing the data msg and the identification information id using a one-to-one signature key to a gateway 3, and the gateway 3 transmits [msg, id, type, tag] received from each of the terminal devices 5 to 7 to a server 1. When the signature system is an aggregate signature system, each of the terminal devices 5 to 7 transmits [msg, id, type, tag' (=tag generated by signing using the aggregate signature key)] to the gateway 3, and the gateway 3 transmits the aggregate tag a_tag and [msg, id] generated by signing msg, id, tag' using the aggregate signature key to the server 1.SELECTED DRAWING: Figure 1

A method for aggregating digital signatures includes receiving first data packages from signers, each first data package including a signer identifier, a payload, and a payload signature; verifying the payload signatures; bundling correctly signed payloads into a batch; obtaining a batch digest, and proofs of inclusion of the payloads in the batch. In some embodiments, the method further includes sending second data packages including the batch digest and a respective proof of inclusion to the signers, the respective proof of inclusion proving that the payload of the respective signer is included in the batch; receiving third data packages from the signers, each third data package including the signer identifier, and a respective batch digest signature. The method may additionally include verifying the batch digest signatures; aggregating correctly signed batch digest signatures; and including the aggregated batch digest signature in the batch.

The invention discloses an Internet of Vehicles cross-domain authentication and key agreement method based on a double-chain structure. The method comprises the following steps: generating system public parameters based on a trusted authority and writing the system public parameters into a main chain; generating a corresponding identity encryption value, a reputation value, an area number and a vehicle and road side unit binding value based on the road side unit registration information; generating a virtual identity, a secret value and a binding parameter of the vehicle based on the vehicle user registration information; the vehicle obtains a binding value of the vehicle and the roadside unit based on the binding parameter and initiates authentication to the roadside unit to obtain an area number; when the vehicle needs cross-domain communication, the vehicle generates a hidden identity and a cross-domain request based on target area verification node information, and a verification node generates an aggregation signature and an encryption seed after verifying the cross-domain request; the main node verifies the legality of the vehicle based on the aggregation signature, and decrypts the encrypted seed to obtain a seed; and the main node queries in the main chain based on the area number and the virtual identity of the vehicle to obtain a secret value, and verifies the session key based on the secret value and the seed.

The present invention provides a heterogeneous aggregate signature system for a verification center, comprising: the verification center obtains a signature sequence (ID i ,m i ,R i ,S i ,T i ), calculate the ID i is the identity information of each signing terminal; m i is the message to be encrypted; T i is the timestamp; S i is the characteristic code of each signature terminal; R i =r i P, r i The parameter is randomly selected by each signing terminal; the equation is calculated and verified based on the signature code of each signing terminal type. If true, the signatures of n user terminals are verified successfully. This invention provides a system that, by rationally setting signature codes for aggregated verification, enables heterogeneous signing terminals to sign based on their respective public key systems, with the verification center then performing unified aggregated verification. This reduces the verifier's system initialization and signature verification overhead, and provides signature and authentication services for users of different cryptographic systems.

The invention discloses a trusted data aggregation method and system for a large-scale distributed intelligent terminal. The method comprises the following steps: step 1, initializing and defining public parameters and private parameters of each entity of an access layer; step 2, the intelligent terminal of the end layer converts the multi-dimensional data into single data for encryption and signature by using the parameters in the step 1), sends the encrypted data and the signature to an edge aggregator of the edge layer, and sends the signature to a block chain of the chain layer at the same time; step 3, an edge aggregator of the edge layer performs weighted aggregation on the encrypted data in the step 2), aggregates signatures, and sends the signatures to a control center of the cloud layer and a block chain of the chain layer; and step 4, the control center of the cloud layer decrypts by using the aggregated data in the step 3) to obtain a single-dimensional data aggregation value, and the block chain of the chain layer performs signature verification by using the aggregated signature value sent in the step 3) and the single-dimensional data aggregation value decrypted by the control center.

The application discloses a kind of high efficiency and privacy protection asynchronous payment method based on block chain, belong to the field of block chain privacy protection technology.This method supports the case where multiple transactions are generated in the system to protect user privacy.The signature of all transactions of the user is aggregated into a single aggregate signature for aggregate verification.This method extends the single verification of locally verifiable signature to subset verification.Later, without knowing all user transactions, the subset of transactions that need to be delayed can be decompressed from this aggregate signature.The method deploys a server to provide a time key so that the delayed payment service provider can only rewrite the on-chain transaction at a specific point in time.Follow-up changes to the transaction through the trapdoor of chameleon hashing only require node network verification, saving time and arithmetic capability compared to generating a new transaction.The method has practical security features and more acceptable efficiency in terms of computational complexity and communication overhead.

The invention discloses an updatable signature method for detecting a forged signature, and mainly solves the problem that an attacker forgery a signature and uploads the signature to a cloud server in an updating gap in the prior art, and the problem that the server and the attacker collude. The method comprises the following steps of: after a signer signs a message, carrying out aggregation operation on an obtained signature and an aggregation signature; the signers negotiate a secret value with the server, respectively use the secret value to calculate an update token, and then the signers use the update token to update the secret key and sign; after the verifier verifies the signature, the server detects and removes the forged signature, and then updates a message-signature pair stored in the server; the signer checks whether the server colludes with the attacker. According to the method, the aggregation signature technology is used in the signature process, detection and removal of forged signatures are achieved, and the protection level of a cloud service system is greatly enhanced.

Various aspects of the subject technology relate to systems, methods, and machine-readable media for cross-chain communication in a blockchain platform. Various aspects may include accepting, at a first blockchain, a first transaction including a message and a message payload. Aspects may also include validating, at the first blockchain, the message by signing the message using signature keys of one or more validators in a first set of validators of the first blockchain. Aspects may also include generating an aggregate signature based on the signature keys of the one or more validators in a first set of validators. Aspects may also include submitting a second transaction on to a second blockchain, the second transaction including the message and the aggregate signature. Aspects may include validating, at the second blockchain, the second transaction based on a shared registry.

A consensus method, system, and consensus node. The method includes: determining a consensus node within a consensus group initiating a consensus proposal in a current round of consensus based on a random number from a previous round, the determined consensus node initiating the consensus proposal; each consensus node within the consensus node group signing the consensus proposal using its own first private key share in a threshold signature algorithm to generate a first signature share, and broadcasting the first signature share to other consensus nodes within the consensus group; consensus nodes that have collected a threshold number of first signature shares using a first recovery function in the threshold signature algorithm to recover a first aggregate signature, and broadcasting the first aggregate signature and the corresponding first aggregate public key to a blockchain network; blockchain nodes that have received the first aggregate signature and the first aggregate public key verifying the first aggregate signature using the first aggregate public key, and upon successful verification, determining the consensus proposal corresponding to the first aggregate signature as the current consensus result.

The invention discloses a log synchronization method, system and device and a medium, and relates to the technical field of block chains. The method of the main node comprises the following steps: acquiring a request message sent by a client, and performing validity verification on a signature of the client; in response to the fact that a first verification result of the client signature is valid, adding the request message to a main node account book, and broadcasting a log entry with the request message to all slave nodes, so that each slave node feeds back a part of signature to which the slave node belongs; generating an aggregated signature according to the signatures of all the parts; generating a zero-knowledge proof according to the request message; broadcasting the aggregated signature and the zero-knowledge proof to each slave node, so that each slave node performs validity verification on the log entry, the aggregated signature and the zero-knowledge proof, and feeds back a second verification result; and according to each second verification result, submitting the log entry and broadcasting a log copy message, so that each slave node copies the log entry into a slave node account book. According to the scheme, the safety of the distributed system is improved.

The present invention relates to the field of information security, and specifically refers to an RSA multiple blind signature method and system based on identity authentication. The method includes RSA initialization, CA public key certificate registration, public key certificate exchange, public key acquisition and verification, information encryption, signature initiation and multiple signatures, signature reception and verification, information sending, and information reception. The present invention uses the RSA algorithm to encrypt information, and at the same time adopts the CA authentication and local public key sharing mechanism to realize the authentication of message signatures, preventing impersonation of signature initiation and impersonation of signatures; the present invention adopts a scatter-type signature and identity authentication mechanism to realize the traceability of incorrect signatures and prevent the overall signature from failing due to a single incorrect signature, which can effectively replace the aggregate signature, and the time complexity only changes from 1 to O(n); the system includes a key generation tool, a data encryption and decryption module, a data signature and verification module, a trusted certification authority CA, an information storage device, and a transaction processor.

The present invention proposes a secure and auditable IoT data sharing system and method based on blockchain, which uses blockchain technology to improve the security of IoT data sharing. Attribute-based encryption is used to achieve fine-grained control of IoT data access rights, and outsourced decryption technology is used to reduce the computing overhead of the user end. A core function of this system is to control the number of user visits, and use algorithms such as synchronous aggregate signatures and verifiable random functions to manage each user's visit. In the paid use model, the system allocates a limited number of IoT data access rights based on the user's payment for the data. At the same time, the smart contract function of the blockchain provides the system with user management, signature verification and access auditing functions.

The invention relates to the technical field of block chain security and data asset management, and discloses a data asset life cycle management system based on a block chain. And encryption group parameters and generators are generated and checked through a secure random source, so that the randomness and the anti-attack capability of a bottom-layer password system are ensured. And a secret polynomial is adopted to segment the master key and distribute the master key to each node, so that distributed key management is realized, and the risk of single-point loss is reduced. Attributes are automatically judged during asset registration, the life cycle stage is accurately mapped, and management automation and state tracking are improved. A standardized event message is constructed for each asset state change, and node part signature and threshold aggregation signature are adopted to ensure the consistency and non-tampering property of an audit chain. And the private key share is dynamically updated during node change or period remodeling, so that the risk of long-term key leakage is reduced. After the assets are terminated, all keys are automatically destroyed, only necessary chain records are left, and the residual keys are prevented from being abused.

The invention provides a trusted data space data interaction method based on a block chain oracle machine, and relates to the technical field of block chains, and the method comprises the steps: receiving a data packet sent by a data provider; performing BLS aggregation signature verification on the BLS signature data, recalculating a local commitment value, comparing the local commitment value with a vector commitment value to confirm content integrity, and judging data admission only after the dual verification is passed; and in response to a data request of a data user for a target data item, obtaining the original data, the digital signature and the Merkle member proof corresponding to the target data item based on the Merkle DAG data structure, generating a verifiable object, and returning the verifiable object to the data user. The block chain oracle machine is introduced as a trusted data space access data connector, and verifiable access and traceable circulation of data resources are realized by constructing a trusted bridging link among the data resources, the block chain oracle machine data connector, the block chain account book and the trusted data space.

This invention relates to the field of secure arraying technology for intelligent nodes, and discloses a lightweight secure arraying method for mobile intelligent nodes. The method includes: a system initialization phase generating elliptic curve formula parameters and an IPFS public key set; a public key validity verification phase using Groth16 zk-SNARK for efficient proof of anonymous public key ownership; a cross-domain authentication phase generating a one-time temporary regional identifier and updating the IPFS set; a signature generation phase employing a short-ring signature algorithm to construct an aggregated signature to support efficient batch signature verification; and a traceability phase extracting traceable factors to locate the true signer. This invention balances node anonymity, lightweight design, and traceability, making it suitable for resource-constrained scenarios such as connected vehicles and the Internet of Things.

The embodiment of the invention provides a data aggregation method and device, and the method comprises the steps: an edge gateway carries out the aggregation operation of data from a plurality of data producers, and generates an aggregation signature, the data is a ciphertext which is encrypted and digitally signed by the corresponding data producers, and the aggregation signature is generated by the edge gateway; by means of the data aggregation method and device, the problem that an existing industrial internet data aggregation scheme is not comprehensive in consideration in the aspect of data storage safety is solved, and then the privacy and integrity of the data are guaranteed.

The embodiment of the application discloses a kind of vehicle ad hoc network efficient aggregation anonymous verification method and related device, the method is verified based on the freshness of time stamp first, guarantee the freshness of time stamp from source;Then the validity of single signature is verified one by one, eliminate received invalid signature;Finally, aggregate signature verification is carried out, and the overall validity of all signatures can be verified by once bilinear pairing operation, compared with the verification of traditional method one by one, multiple bilinear pairing operations are needed, and the calculation complexity can be reduced.In high concurrency scene, processing delay is shortened from seconds to hundreds of milliseconds, which can effectively solve the problem of low efficiency of dynamic message authentication in Internet of Things, especially in vehicle networking, and meet the real-time demand.In addition, the application also introduces the smart contract and distributed digital identity verification technology of block chain, which can prevent malicious attacks of Internet of Things virus or node, and it is particularly important to improve privacy protection and prevent privacy leakage.

The application relates to a signature-based set semantic similarity connection method, and belongs to the fields of databases and information retrieval. The method comprises four parts: firstly, a classification tree construction step: a classification tree is constructed according to a WordNet knowledge base given a data set; secondly, a set signature step: each set in the data set is signed to obtain a corresponding signature data set; thirdly, a data preprocessing step: the sets in the signature data set are sorted to obtain a sorted data set; and finally, a connection processing step: self-connection is performed on the sets in the sorted data set to obtain a set of semantic similarity results. The method is based on signature prefix filtering technology and length filtering technology, and finally realizes the set semantic similarity connection method, so that the set semantic connection efficiency can be effectively improved.