7 results about "Blind signature" patented technology

The invention relates to the field of Internet of Things security, block chains and privacy computing, and discloses a privacy protection and amount variable multi-hop payment method and system for autonomous Internet of Things resource scheduling. According to the method, network topology and weight are hidden through multi-party security calculation to select an optimal payment path; the sender generates a Pedersen commitment and a zero-knowledge proof to hide and verify the transaction amount; the relay node performs homomorphic updating on the channel balance commitment after verification and certification, and generates a blind signature bound with a channel state for confirmation; the receiver verifies all signatures and certificates and ensures the conservation of the total amount of funds in the multi-hop payment process through a balance consistency verification function; and finally, settlement or arbitration is completed by the on-chain smart contract. According to the invention, dual privacy protection of payment amount and path is realized, variable amount is supported, and the method is suitable for crowdsourcing logistics, resource transaction and other Internet of Things scenes.

The invention discloses a blind signature and chameleon Hash-based dual-certificate DID management method and system, and the method comprises a registration stage, a verification stage and an updating stage: the registration stage: a user terminal sends a registration message, a blind message and an original identity Hash value as identity Hash, a registration mechanism generates a blind signature after verification, issues a registration certificate, and sends the registration certificate to a user terminal; the user terminal locally generates a verifiable certificate after blind verification; in the verification stage, the server calls the smart contract, and verifiable certificate validity is verified based on a chameleon hash function; in the updating stage, the user terminal generates a new verifiable certificate by using the chameleon Hash controllable collision characteristic, and chain identification updating is completed after verification of the intelligent contract. According to the method, authority is split through a double-certificate architecture, blind signature and chameleon hash technologies are fused, autonomous control of user identities, privacy protection and flexible updating are realized, and verification security and efficiency are improved.

The application relates to the technical field of anonymous communication and provides an anonymous communication method and system based on blind signature and a medium, the method comprising the following steps: a sender generates a blind signature request containing public metadata and a message token, sends the blind signature request to a signature server, and the signature server performs blind signature; the sender performs de-blinding on the received blind signature result, obtains an anonymous token, and sends an authorization request to a bulletin board server; the bulletin board server verifies the validity of the anonymous token, allocates a mailbox and a corresponding writing time window to the sender; the sender obtains the writing permission of the mailbox within the time window, and then delivers a ciphertext to the mailbox; a receiver sends a private information retrieval request to the bulletin board server based on the mailbox identifier informed by the sender, and receives returned response ciphertext; and the receiver uses a PIR private key and a session key to decrypt the response ciphertext, and obtains a plaintext message. The application guarantees the strong privacy of both communication parties and realizes the safe transmission of confidential messages.

The invention relates to an NTRU lattice-based batch blind signature round optimization method and device, equipment and a medium, and the method comprises the steps: after a server side receives a first round of information, if first zero-knowledge proof verification is passed, taking each to-be-signed vector as an input, generating an original image pair of the to-be-signed vector, and sending the original image pair to the server side; generating a second round of message according to an original image pair set constructed by all the original image pairs meeting the length constraint, and sending the second round of message to the user side; after receiving the second round of message, the user side constructs a second zero knowledge proof based on the system main public key, all the first hash values in the first round of message, the message commitment, the random number commitment and all the primary image pairs in the second round of message, and constructs a final signature through all the first hash values in the first round of message and the second zero knowledge proof; and the verifier verifies the second zero-knowledge proof, and if the verification is passed, the final signature is determined to be valid. According to the application, the signature and interaction cannot be associated, and the legality and privacy of the signature are guaranteed.

The invention provides a collaborative signature method and device, equipment, a medium and a program product, and the method is characterized in that the method comprises the steps: obtaining a public key, and transmitting the public key to a block chain network for storage; dynamically updating the credibility score of each node in the node cluster through historical behavior data recorded by a block chain network; on the basis of a preset lowest credibility accumulation threshold value, according to the credibility score of each node, effective signature nodes and a dynamic threshold value are determined, and the dynamic threshold value represents the number of the nodes participating in signature; obtaining blind signature parameters based on the effective signature nodes, and sending the aggregated blind signature parameters to a requester; and receiving a transaction ciphertext sent by the requester, generating a signature fragment corresponding to each effective signature node based on the transaction ciphertext, and sending the signature fragments to the requester. According to the invention, a single-point fault can be avoided, and the signature security and efficiency are balanced.

The present application relates to the technical field of identity authentication, and relates to a traceable blind signature data protection system based on SM9. A server initializes data protection parameters and discloses them. The server determines a private key of a first terminal and a data tracking label according to the data protection parameters, and sends them to the first terminal. The first terminal blinds transaction data according to the data protection parameters, the private key of the first terminal and the data tracking label, and determines blinded data. The blinded data is blindly signed through an SM9 algorithm. A deblinding key of the blindly signed blinded data is generated. The blindly signed blinded data is sent to the server. A second terminal purchases the blinded data through the server. The second terminal sends a decryption request and a purchase voucher to the first terminal and receives the deblinding key sent by the first terminal. The blindly signed blinded data is recovered according to the deblinding key. It can be ensured that the server and the second terminal cannot know the original data content before obtaining the deblinding key.

The present application relates to a kind of based on lattice blind signature and the transaction method of fragmented blockchain, comprising: according to the input of transaction, the Merkle tree of sharding leader is generated, the Merkle tree is blinded according to the public key of other nodes, sharding leader node executes unblinding algorithm and generates blind signature, other nodes are verified and adopted to blind signature, leader node collects the blind signature of all other nodes and does BFT consensus result verification, and the commitment signature of Merkle tree root is generated after verification;The information of each input and the commitment signature of Merkle tree root are sent to the leader of other input-output sharding of relevant transaction to determine whether the input of transaction is available, correct transaction is put into valid transaction pool;Sharding leader packs correct transaction into block and broadcasts to other nodes, carries out BFT consensus, completes block chain, and updates the transaction input state in utxo pool, and completes transaction.