69 results about "Distributed key generation" patented technology

A computer-implemented method and system for privacy-preserving location verification in distributed networks comprises initializing a multi-modal biometric authentication system on a user device, generating cryptographic keys using a distributed key generation protocol, binding the cryptographic keys to biometric templates using a fuzzy vault scheme, constructing and broadcasting encrypted location beacons, and generating zero-knowledge proofs of location claims. The system includes user devices equipped with biometric sensors and verifier devices configured to validate location claims and maintain consensus in a blockchain network. The method implements real-time liveness detection for multiple biometric input types, executes fault-tolerant consensus algorithms with privacy preservation, and maintains a dual-scoring mechanism comprising device trust scores and user reputation scores. The system enables secure location verification while preserving user privacy through cryptographic protocols and biometric authentication in decentralized environments.

The invention discloses a multi-party collaborative signature management method and system based on a key segmentation technology, and relates to the technical field of fragmentation encryption, and the method comprises the steps: initializing data in an encryption system, collecting behavior data when a key anomaly occurs in history, deploying an AI anomaly detection model, generating a master key through a distributed key generation protocol, and generating a multi-party collaborative signature in the encryption system; deriving time by using a hierarchical deterministic algorithm, segmenting a master key to form key fragments, and distributing each fragment to different nodes; formulating a periodic rotation triggering mechanism; calculating an abnormal score of each node, judging whether each node has an abnormal risk or not, and marking the abnormal risk; for the marked nodes with the abnormal risk, fragments are redistributed for alternation; dynamically adjusting the threshold according to the abnormal score; a client initiates a signature request, abnormal nodes are eliminated, fragment node aggregation is screened, and collaborative signature is carried out.

The invention relates to the fields of cryptographic algorithms and homomorphic encryption, in particular to an anti-quantum-attack homomorphic encryption method. Along with increasing demands of outsourcing computing and privacy protection application in a multi-user scene, multi-key homomorphic encryption becomes an important research direction. The construction of a traditional multi-key homomorphic encryption scheme generally depends on a common random character string (CRS) model, and a trusted party needs to generate a common parameter for a public key so as to support calculation on a joint ciphertext. Due to the dependence on the central trusted mechanism, the anti-attack capability and the decentralization characteristic of the system are greatly reduced. In order to avoid excessive dependence on trusted third parties and public parameters, a distributed key generation protocol is used in the invention, all users are enabled to independently generate keys thereof, and ciphertexts of a plurality of users are expanded to the same dimension through a ciphertext expansion technology, so that the encryption efficiency is improved. Therefore, multi-key homomorphic encryption in a multi-user scene is realized without depending on a trusted third party, a lattice-based CRS-free multi-key homomorphic encryption method is provided, and the security and decentration characteristic of the scheme are enhanced. Furthermore, the invention provides a directional decryption mechanism and introduces the directional decryption mechanism into the scheme, the public key information of the target user is embedded into the ciphertext, it is ensured that only the specific target user can decrypt the ciphertext after homomorphic operation, and more flexible privacy protection is provided.

The invention discloses a distributed key generation method and device based on an SM2 algorithm, a medium and equipment. The method comprises the following steps: determining a class group encryption key, a class group decryption key and a corresponding first zero knowledge proof through public parameters generated based on the SM2 distributed key; each participant shares respective secret share based on the class group encryption key, the class group decryption key and the first zero-knowledge proof, and creates a second zero-knowledge proof indicating that sharing is correct; each parameter party collects honest distribution shares and decryption shares based on the second zero knowledge proof, calculates a part of private keys and a part of public keys according to the decrypted secret shares, and creates a third zero knowledge proof indicating correct decryption; according to the third zero knowledge proof, partial public keys of participants correctly executing decryption operation are determined to reconstruct a global public key, the secret is shared by using a polynomial, each participant can contribute a part of shares, and a distributed secret key is generated without any credible setting.

Systems and methods are disclosed for security through multi-party computation (MPC). In some examples, a system generates, at a first device and using a first private key share (of a plurality of private key shares). The plurality of private key shares each correspond to different devices. The system receives, from one or more additional devices, one or more additional partial signatures that are generated using one or more additional private key shares (of the plurality of private key shares). The system identifies that a total amount of partial signatures associated with the transaction is meets or exceeds a minimum threshold amount of partial signatures. The system aggregates the first partial signature and the one or more additional partial signatures to generate a signature, and facilitates processing of a transaction using the signature and a distributed ledger.

The invention belongs to the technical field of intelligent traffic system data privacy protection, and discloses a traffic flow federated security prediction method based on distributed homomorphic encryption, and the method comprises the steps: constructing a vehicle-road cloud integrated network architecture, constructing a local model and a global model based on LSTM, and forming a federated model; cooperatively generating a distributed key based on a road infrastructure node and a cloud platform node, and performing homomorphic encryption and training on the federated model; and traffic flow prediction is carried out based on the trained federal model. According to the method, the confidentiality of the model training process is higher, the confidentiality of shared model parameters can be ensured through the distributed key generation and homomorphic encryption computing technology, and inference attack threats based on model parameter analysis are avoided. According to the invention, the defect of data privacy in an existing traffic flow prediction system can be overcome, and an effective support technology is provided for intelligent traffic management.

Method and system for generating digital signature following one or more secure protocols based on a threshold additively homomorphic encryption (TAHE) over a broadcast channel, where a threshold of parties of a decentralized network produces digital signature by following a Universally Composable secure protocol configured to output Elliptic curve digital signature algorithm (ECDSA) signature or a Schnorr signature. At least one client may cooperate with the threshold of parties to generate digital signature, or threshold of parties may cooperate to generate digital signature without a client. Method may include additively homomorphic encryption (AHE) distributed key generation (DKG), ECDSA / Schnorr DKG, ECDSA / Schnorr presigning, providing ECDSA / Schnorr child keys, ECDSA / Schnorr signing, wallet transfer and / or network reconfiguration.

The invention provides a distributed key generation method and device based on quantum random numbers, a medium and equipment, and belongs to the technical field of quantum security. According to the method, quantum random number generators are configured for nodes of the block chain, and the nodes generate self-certification information by using quantum random numbers provided by the quantum random number generators and broadcast the self-certification information among the nodes; and after the node successfully verifies the received proof information, generating a signature private key, a verification public key and a global public key of the node by using a quantum random number provided by a quantum random number generator. According to the invention, the quantum random number with true randomness is adopted to generate the distributed key, so that the security of the distributed key is improved.

The invention discloses a unified key management method and device for a distributed password service component, and aims to solve the problems of single-point failure, consistency deficiency and insufficient life cycle management and control of existing key management. According to the method, based on a distributed key generation protocol, Shamir secret sharing, PBFT consensus and Lagrange interpolation, key generation, distributed storage, safe distribution and dynamic rotation whole-process management and control are achieved. The device is composed of n nodes including a processor, a memory and a communication and key processing module, and supports encrypted storage, secure communication and consensus collaboration. Security is guaranteed through a threshold mechanism, hash verification and a hash chain technology, availability is improved through SDN optimization and failover, and nodes and parameters can be flexibly adapted and expanded. The method is applied to scenes such as a power grid, gives consideration to safety, availability and compliance, and is suitable for unified key management of distributed system password services.

The invention discloses a relay cross-chain method and system applied to block chain cross-chain, and belongs to the technical field of block chain interoperation. The method comprises the following steps that: in an anonymous committee election stage, a candidate node performs anonymous drawing by using an anonymous verifiable random function combined with a weight and a temporary identity key; in the key generation stage, an asynchronous distributed key generation protocol is adopted, a reliable broadcast protocol is combined, and a threshold signature private key share is generated on the premise that a complete private key does not need to be reconstructed; in a cross-chain consensus stage, a committee member generates a threshold signature share containing an identity bit vector, an aggregation node encrypts the bit vector by using an accountability public key and generates a zero-knowledge proof, and a binding relationship between an identity ciphertext and an aggregation signature is constructed. According to the invention, identity privacy protection of a whole cross-chain verification process is realized, and the problem of key generation deadlock in an asynchronous network environment is solved.

The invention discloses a multi-authority personal data access control method and system based on a block chain, and relates to the technical field of information security, and the method comprises the steps: selecting a large prime number, defining an elliptic curve, constructing a finite field, and generating a master key and an attribute key; submitting a registration application, generating verification parameters by using random numbers and hash, and distributing keys according to user attributes; the AES is adopted to encrypt data, and an access strategy is set by using an attribute encryption key; and extracting block chain key information, and requesting the CCC to output decryption parameters in combination with own attributes. According to the method, multi-authoritative distributed key generation is adopted, and data fine-grained access control is realized in combination with attribute-based and AES (Advanced Encryption Standard) encryption. Through cooperative storage of the IPFS and the block chain, data integrity and non-tampering are ensured; the cloud computing center undertakes partial decryption computing, reduces the load of the terminal, and guarantees the security of the key.

A method for implementing distributed key generation in a blockchain by a blockchain node includes: generating n secret shares, retaining a share and respectively encrypting a remaining n−1 secret shares by using keys of receivers, generating a public verification parameter corresponding to a secret share of the blockchain node, generating a zero-knowledge proof indicating that the secret share of the blockchain node and the public verification parameter match, sending the secret share, the public verification parameter, and the zero-knowledge proof to an on-chain contract by using a transaction, verifying, by the on-chain contract based on the zero-knowledge proof, that the encrypted secret share and the public verification parameter match, obtaining, from contract information, a verified secret share corresponding to the blockchain node, performing decryption by using a key of the blockchain node, and calculating a private key share of the blockchain node based on a local secret share.

The present invention discloses an SM2 threshold signature system based on dynamic secret sharing, which relates to the field of information security technology. The system includes: an initialization module, a distributed key generation module, a signature module and a verification module; the initialization module is used to initialize public parameters; the distributed key generation module is connected to the initialization module, and is used to generate a secret share based on the initialized public parameters; the signature module is connected to the distributed key generation module, and is used to generate a signature pair based on the public parameters and the secret share; the verification module is connected to the signature module, and is used to verify the signature pair. In view of the fact that the existing SM2 threshold signature algorithm cannot use the original signature private key to ensure that the external signature public key remains unchanged when the number of participating users needs to change or the threshold value changes, the present invention uses a distributed key generation module to generate a secret share, which can dynamically add or delete the threshold value and the number of participating users under the premise of ensuring that the original signature private key remains unchanged.

Systems and methods for distributed key generation is provided. In some embodiments, a public key and a private key are generated using elliptical curve cryptography (ECC) at a group of trusted parties. In some cases, an elliptical curve digital signature algorithm may be employed. Each party also generates a commitment and a blinding factor. The blinding factor may be a randomized polynomial integer. The parties use the commitments from the other parties to validate the public keys before receipt and combining the public keys into a group / aggregate public key. Content encryption keys (CEK) are then encrypted at each of the trusted parties using these aggregate public keys to generate wrapped content encryption keys (WCEK). Private keys are sharded and a sharded private key is generated at each party using the pieces of shards received by the trusted party. Subsequently, criteria may be received that allows for the release of these sharded private keys back to a trusted environment / enclave.

The present application belongs to the technical field of information security, and particularly relates to a BLS traceable security threshold signature method and system based on distributed key generation. The method comprises the following steps: S1, generating a bilinear pairing environment, and initializing public security parameters; S2, determining a group mapping relationship based on a symmetric balanced incomplete block design, each participant interacting in a group to generate respective key shares and a system global public key; S3, a signer performing partial signature and zero-knowledge proof corresponding to the partial signature on a message according to the corresponding key share; S4, an aggregator collecting and verifying the partial signature, screening out an effective signature set, aggregating to generate a final signature, and generating a commitment ciphertext; S5, a verifier verifying the final signature, and confirming the signature as valid if the verification is passed; S6, when the verification is not passed, a tracing mechanism is activated, and a tracer traces the signature group; and S7, according to the group mapping relationship, regularly performing active refreshing of the key shares.

The present invention belongs to the field of blockchain technology, and provides a distributed oracle implementation method and system based on threshold signature. The method is applied to the oracle network, including: receiving a request event sent by the blockchain to establish a TLS connection with a specified external data source; according to the request event, the nodes with private key shares use their own private key shares to sign to obtain their own signature shares, and broadcast; if the number of signature shares received by any node in the oracle network exceeds the threshold value t, a complete signature is constructed and sent to the blockchain; so that the blockchain uses the public key to verify the complete signature, and obtains the callback function specified by the user contract according to the request identifier, and executes the result of the callback function and returns it to the user contract; wherein, the private key share and public key are: the distributed key generation protocol is used to generate the private key share and public key for each node. The present invention will not restore the complete key during the signing process.

The invention discloses an MPC threshold signature method and system suitable for HSM, and relates to the technical field of information security and cryptography, and the method comprises the steps: a management module manages a plurality of hardware security modules HSM, coordinates a key generation module of each HSM to execute a distributed key generation protocol DKG, and enables a private key fragment to be directly generated in each HSM and to be encrypted and stored; the MPC threshold signature module receives a to-be-signed message of an application APP and user certificate information, calls the management module to perform identity verification on the user certificate information, and obtains a target HSM node list associated with a user passing verification; the MPC threshold signature module schedules a threshold signature module with at least a threshold value of t HSM nodes according to the target HSM node list, and MPC threshold signature operation is executed in each HSM based on private key fragments; and the MPC threshold signature module receives partial signatures returned by each HSM, and aggregates the partial signatures into a standard digital signature for realizing efficient, compliant and single-point fault resistant digital signature operation on the premise of ensuring absolute security of the private key.

The invention discloses a double-path verifiable threshold signature-based block chain right confirmation and responsibility investigation method, which comprises the following steps of: S1, receiving right confirmation data, processing the data to obtain normalized data, and calculating a data abstract of the normalized data; submitting the data abstract and the associated information thereof to a block chain for evidence storage to form a right confirmation request record; s2, in response to the right confirmation request record, selecting a committee member set from candidate nodes based on a preset strategy, and cooperatively generating a global public key and a private key share corresponding to each committee member by the committee member set through a distributed key generation protocol; and S3, each committee member generates a partial signature for the data abstract by using the private key share of the committee member, and generates a verifiable proof for proving the correctness of the calculation process of the partial signature of the committee member at the same time. According to the invention, independent verification and accurate responsibility tracing of individual signature behaviors of committee members can be realized.

Embodiments of the invention relate to a computer-implemented method for generating verification keys of a public-key signature scheme in a distributed network. The method comprises performing, by a subset of the nodes of a first subnetwork of nodes, a first distributed key generation protocol, the first distributed key generation protocol being configured to generate jointly a verification key for the first subnetwork and a plurality of corresponding secret key shares for the nodes of the first subnetwork. The method further comprises a step of performing, for a second subnetwork, by a subset of the plurality of nodes of the first subnetwork, a second distributed key generation protocol, the second distributed key generation protocol being configured to generate jointly a verification key of the second subnetwork and a plurality of corresponding secret key shares for the nodes of the second subnetwork. A further step comprises signing, by a subset of the nodes of the first subnetwork, the verification key of the second subnetwork with a permissible subset of the secret key shares of the nodes of the first subnetwork, thereby generating a joint signature on the verification key of the second subnetwork.Further aspects relate to a distributed network, a node of a distributed network and corresponding computer program products.

The invention discloses an asynchronous distributed key generation method and device. The method comprises a sharing stage, a negotiation stage, a random extraction stage and a key derivation stage which are executed in sequence. In the sharing stage, an asynchronous complete secret sharing protocol is adopted, and secret share distribution is achieved through the steps of sending, confirmation, preparation and amplification; in the negotiation stage, consensus screening is carried out on terminated secret sharing instances based on a multi-valued verification Byzantine negotiation protocol; in the random extraction stage, a negotiation result is operated by using an ultra-reversible matrix to generate an intermediate parameter; and in the key derivation stage, a key related result is finally output through an online error correction algorithm and Lagrange interpolation calculation. The method gets rid of dependence on public key infrastructure and credible setting, relieves the contradiction between throughput and delay, improves the security, reliability and anti-review performance of the system, and is suitable for a large-scale distributed system or a resource limited environment.

A method for realizing distributed key generation on a blockchain, comprising: S1: each node generates n secret shares, retains one share itself, and encrypts the remaining n-1 secret shares with a receiver key; each node generates a public verification parameter corresponding to its own secret share; each node generates a third zero-knowledge proof that its own secret share matches the corresponding public verification parameter; S2: each node sends the secret share, the public verification parameter, and the third zero-knowledge proof generated by itself to an on-chain contract through the same transaction or different transactions; S3: the on-chain contract verifies that the encrypted secret share and the corresponding public verification parameter match through the third zero-knowledge proof; and S4: each node obtains the verified secret share with the receiver being itself from the contract information, decrypts the secret share with its own key, and calculates its own private key share in combination with the local secret share.

The application provides a kind of dynamic guardian secret sharing method and system based on blockchain, belong to encryption field, method includes: based on distributed key generation method, group public-private key pair is generated according to system parameter, threshold key pair and public-private key pair of each member in guardian committee;Threshold key share of each member is encrypted to obtain chain share;Based on the joining application initiated by new member, member private key is used to decrypt chain share and calculate Lagrange factor;Determine the first decryption share based on Lagrange factor;Based on the decryption application initiated by new member, Lagrange interpolation method threshold reconstruction is carried out according to threshold key share and chain share, to determine the second decryption share;Determine the threshold key pair of new member according to the first decryption share, the second decryption share and system parameter.The application can ensure that new member reconstructs own secret sharing share without knowing the content of key and the share of remaining members.

The invention discloses a vehicle-mounted CAN (Controller Area Network) bus safety communication method based on attribute grouping. The method comprises the following steps: firstly, selecting a master key, a public key, a hash function and related parameters; the electronic control unit ECU registers with a gateway electronic control unit GECU; in the key generation stage, the GECU groups the ECUs and distributes key generation parameters to the ECUs in the groups, and the ECUs in the groups calculate group keys according to the key generation parameters; the ECUs in the group communicate with each other by using the group key; and in the key updating and ECU re-joining stage, the ECU can update the key without interaction. Through constructing a group key generation mechanism based on an access structure tree, group communication based on ECU function attributes is realized. And a key self-authentication mechanism is introduced, so that the interaction turns between the ECUs are reduced, and the communication load is reduced. The method is suitable for a vehicle-mounted network dynamic scene, and effectively resists attacks such as counterfeiting and replaying.

The invention discloses a traceable multi-signature method supporting a distributed aggregator and lightweight setting, which is characterized in that a decentralized signature generation mechanism is realized by adopting a cryptographic method comprising bilinear pairing, a linear homomorphic time lock, a cryptographic hash function and a BLS signature; the method specifically comprises the steps of system initialization, key generation, authorization generation and aggregation, prompt generation, partial signature and verification, authorization verification, signature aggregation, authorization revocation, signature verification and the like. Compared with the prior art, the method has a decentralized key generation mechanism, a distributed aggregator mechanism and a signature accountability function, so that high communication overhead caused by the use of a distributed key generation protocol and a single-point fault possibly caused by excessive dependence on a single aggregator are avoided; and meanwhile, a strong association mechanism between the signer and the final multiple signatures is established, and the signer is responsible for the signature behavior of the signer, so that the problems of low efficiency and high centralization of aggregators caused by dependence on a DKG protocol are effectively solved.

The invention discloses a distributed secret key generation method, device and system based on SM9, and belongs to the technical field of cryptography, firstly, the distributed secret key generation method combines identity password characteristics of an SM9 algorithm and a distributed cooperation mechanism to improve the safety and decentration degree of a secret key generation process. Secondly, a distributed key generation system architecture with multi-node cooperative participation realizes common generation, distribution and reconstruction of keys, and avoids central trust risks. Then, a tamper-resistant and share verification mechanism is introduced, the resistance of the system to malicious nodes is enhanced, and the correctness and confidentiality of the key generation process are guaranteed; and finally, the method also supports a transverse expansion capability, has good expandability and platform independence, and is suitable for construction of various distributed security infrastructures. Therefore, the method can meet the application requirements of high concurrency, low delay and high security of the block chain system.

A distributed key generation system and a key generation method are provided. The distributed key generation system includes a plurality of electronic devices and a server device. Each electronic device sends a data fragment. The server device synthesizes the key according to the data fragments. In this way, the key is not generated in advance, which can reduce the risk of key leakage.

The invention discloses an encryption aggregation method and system for a household micro-grid, and is applied to the technical field of micro-grid group operation control, and the method comprises the steps: obtaining adjustable data of a plurality of household micro-grids; classifying the adjustable data of the plurality of household microgrids to obtain a plurality of to-be-adjusted data groups; and inputting the plurality of to-be-adjustable data groups into a micro-grid group system at least comprising a plurality of household micro-grids for processing to obtain to-be-aggregated ciphertext data, and performing threshold decryption processing on the homomorphic aggregated ciphertext by using a distributed key generation technology to obtain an aggregation result of the micro-grid group system. According to the method provided by the invention, the technical problems of privacy leakage and data security caused by plaintext uploading and user side sensitive operation data transmission in an existing household micro-grid aggregation mode can be solved, so that privacy protection of the original sensitive data of the household micro-grid is realized.

This invention belongs to the field of vehicle-to-everything (V2X) secure communication and blockchain consensus technology, specifically disclosing a trust-driven V2X blockchain consensus method. This method achieves decentralized management of the master key through a distributed key generation protocol, eliminating the traditional Root-TA single-point trust problem. Combining a dynamic trust evaluation mechanism based on Beta distribution with incentive contract design based on a delegate-agent game model, it constructs a trust-driven dynamic PoW consensus mechanism, achieving two-layer dynamic control of global security state and individual reputation level. This invention significantly improves the decentralization, consensus fairness, and operational efficiency of V2X systems while ensuring security and privacy.

The application belongs to the technical field of intelligent transportation system data privacy protection, and discloses a traffic flow federal security prediction method based on distributed homomorphic encryption, which forms a federal model by constructing a vehicle-road cloud integrated network architecture, constructing a local model and a global model based on LSTM; the distributed key is generated based on the cooperation of the road infrastructure node and the cloud platform node, the federal model is homomorphically encrypted and trained; and the trained federal model is used for traffic flow prediction. The method has stronger confidentiality in the model training process, can guarantee the confidentiality of the shared model parameters through distributed key generation and homomorphic encryption calculation technology, and can avoid the threat of inference attack based on model parameter analysis. The application can solve the deficiency of data privacy in the existing traffic flow prediction system and provide effective support technology for intelligent transportation management.

To allow an outsourcer not to need to manage a private key in proxy re-encryption, etc.SOLUTION: A cryptographic system includes a delegation source device that acquires first biometric information and generates a first biometric-based shared key, a delegation source destination device that receives the first biometric-based shared key from the delegation source device and stores it in a memory unit, and a key distribution generation device that acquires second biometric information, generates a second biometric-based shared key, and transmits it to the delegation source destination device, and the delegation source destination device generates a key-based shared key from the difference between the first biometric-based shared key and the second biometric-based shared key using the delegation source's public key and transmits it to the key distribution generation device, and the key distribution generation device generates a re-encryption key from the key-based shared key.SELECTED DRAWING: Figure 5