CN-115859316-B - Anonymous manageable cross-chain privacy protection method based on zero knowledge proof

CN115859316BCN 115859316 BCN115859316 BCN 115859316BCN-115859316-B

Abstract

The invention relates to an anonymous manageable cross-chain privacy protection method based on zero knowledge proof, and belongs to the technical field of network security. Firstly, deploying cross-link intelligent contracts on a main chain and a side chain, connecting a network through a cross-link, then calling the cross-link contracts of transaction chains at two ends on a relay chain by a transaction initiator to generate anonymous transactions, finally, packaging and sending proving information and the transactions to a receiver and the relay chain by a zero knowledge proving algorithm, and completing the transactions by the initiator and the receiver. The invention can protect the privacy information of the user, realize the supervision transaction traceability operation and safely and efficiently perform the cross-chain transaction, and improve the safety of the block chain cross-chain communication in the zero trust environment.

Inventors

SHEN TAO
YANG YINGHONG
YU ZHUO
BAI FENHUA
LIU YINGLI
ZHANG CHI

Assignees

昆明理工大学

Dates

Publication Date: 20260505
Application Date: 20220823

Claims (5)

1. An anonymous manageable cross-chain privacy protection method based on zero knowledge proof is characterized by comprising the following steps of: step1, deploying a cross-link intelligent contract and a flow control contract on a main side chain, and connecting a network by using a cross-link; Step2, the initiator participating in the transaction creates a cross-link transaction, a new transaction address is generated by using a virtual address generator in a cross-link way, and a cross-link intelligent contract is called to lock the transaction to a relay chain; step3, anchoring the asset by the relay chain, verifying the legitimacy of transaction information of both sides, applying for unlocking the asset by the relay chain to finish the transaction, and recording the transaction by the relay chain; Step4, tracing the source by using a virtual address generator according to the transaction record on the relay chain, and broadcasting to both transaction parties; The Step2 specifically comprises the steps that Chain a creates a transaction, calls a cross-Chain intelligent contract to generate the transaction, and corresponds to a source address addr_a and a destination address addr_a ́ of the transaction, wherein addr_a ́ is a virtual address mapped by a virtual address generator to form an anonymous transaction T (addr_a, addr_a ́), and a relay route collects the transaction asset evidence and locks the transaction; The virtual address generator is as follows: Step2.1, selecting a generating function as shown in a formula (2), wherein eta parameters are used for controlling the amplitude of the function, omega controls the cycle size, and beta adjusts a curve in the y-axis direction so that y >0 when x=0 is generated; φ(x)=|η·x·sin(ω·x)+β|,x∈(0,+∞)(2); step2.2, taking a discrete alpha as the sampling density on the x-axis according to formula (3), n as the number of transactions, n=n+1 each time one transaction is added; (3); Step2.3, splicing a 64-bit external address by using a snowflake algorithm, intercepting the last 16 bits of each chain public address as a prefix, fixing the first bit as a sign bit to be 0, generating the last 47 bits by taking the first 47 bits of a y value from a point set, and supplementing the insufficient bits by using 0; Step2.4, delivering the generated virtual address to the cross-link intelligent contract.
2. The anonymous manageable cross-link privacy protection method based on zero-knowledge proof according to claim 1, wherein Step1 is characterized in that an initiator is Chaina, a receiver is Chainb, a relay link network R-Chain is accessed through a relay route, cross-link intelligent contracts are deployed on Chaina and Chainb, and networking operation is completed.
3. The zero knowledge proof-based anonymously manageable cross-chain privacy protection method of claim 1, wherein Step3 is specifically: Step3.1, collecting identity certificates and SPV transaction certificates from both transaction parties by a relay route; R-Chain verifies whether the asset T (addr_a, addr_a ́) meets the transaction, if not, the transaction is aborted, and transaction rollback is performed; Step3.3, if the transaction is satisfied, the transaction is forwarded to the public account address addr_Ra to form a new transaction Tra (T (addr_a ́), and the transaction of the part Chaina is completed; The part of the transaction of Step3.4: chainb is transferred from the public account address addr_Rb of the relay chain to the destination address addr_b ́, then the unlocking transaction is transferred to addr_b by the relay route control, so as to form a new transaction Trb (addr_b ́, addr_b), at the moment, the two parties of the transaction are completed to exchange, and the relay chain records the transaction result.
4. The anonymous manageable cross-chain privacy protection method based on zero-knowledge proof according to claim 1, wherein Step4 specifically comprises tracing a transaction record on a relay chain by using a virtual address generator, broadcasting to both transaction parties after completion, firstly querying the transaction record of a user on a main chain to obtain the transaction order n of the user, inputting n into a generating function phi (x) to obtain a point set A (x, y), generating an external address in a generator, and calculating the intersection of the following formula (1) by both transaction parties by using the point set A a ,A b : Urecord=A a (x(n a ),y)∩A b (x(n b ),y)(1); finally, an anonymous list of transaction records is obtained.
5. The zero knowledge proof-based anonymously manageable cross-chain privacy protection method of claim 3, wherein step3.1 is specifically: step3.1.1, the relay route receives the identity information and SPV proving information from Chaina, extracts the transaction value, verifies whether the value is more than or equal to the value to be achieved by the transaction; Step3.1.2, using Groth16 zero knowledge proof algorithm to generate identity proof, wherein the generated identity proof file has private key, verification key, proof evidence, verification key is put on relay chain to store, proof evidence is put on trade Tra to form new trade certificate.

Description

Anonymous manageable cross-chain privacy protection method based on zero knowledge proof Technical Field The invention relates to an anonymous manageable cross-chain privacy protection method based on zero knowledge proof, and belongs to the technical field of network security. Background Because of the rapid development of blockchain technology, a plurality of blockchain frameworks appear, and the blockchains can be classified into public chains, alliance chains and private chains according to the degree of openness, the blockchains have different standards, different used consensus algorithms, different asset values and huge blockchain networks which are isolated from each other to form different parallel networks, and users need to personally use physical asset anchoring to realize transactions between the two blockchains. Thus, under this need, cross-chain technology has emerged. Cross-chain is a technique for establishing a bridge of cross-blockchain transactions between different blockchains to achieve value exchange or value transfer. It ensures interoperability, atomicity, consistency by using certain protocol standards. The currently verified cross-chain technology has hash time locking, notary mechanism, side chain/relay chain and distributed private key control. In these cross-chain techniques, in order to ensure that the transaction asset amount is accurate, the transaction is truly and effectively performed, and the third party participants collect user transaction information and asset information, so that the privacy disclosure problem exists in the blockchain multiparty transaction. Disclosure of Invention The invention aims to solve the technical problem of providing an anonymous and manageable cross-chain privacy protection method based on zero knowledge proof, which is used for solving the problem of privacy disclosure in a blockchain cross-chain transaction process in the prior art. The technical scheme of the invention is that the anonymous manageable cross-link privacy protection method based on zero knowledge proof is characterized in that firstly, cross-link intelligent contracts are deployed on a main chain and a side chain, virtual address generator contracts are connected with a network through a cross-link, then a transaction initiator calls the cross-link contracts of transaction chains at two ends on a relay chain to generate anonymous transactions, finally, zero knowledge proof algorithm calculation proof information is packaged together with the transactions and sent to a receiver and the relay chain, and the initiator and the receiver finish the transactions. The method comprises the following specific steps: step1, deploying a cross-link intelligent contract and a flow control contract on a main side chain, and connecting a network by using a cross-link. The initiator is Chaina, the receiver is Chainb, the relay link network R-Chain is accessed through the relay route, the cross-link intelligent contracts are deployed on Chaina and Chainb, and the networking operation is completed. Step2, the initiator participating in the transaction creates a cross-link transaction, a new transaction address is generated by using a virtual address generator in a cross-link way, and a cross-link intelligent contract is called to lock the transaction to the relay link. Chaina creates a transaction, calls a cross-link intelligent contract to generate a transaction, corresponds to a source address addr_a and a destination address addr_a ' of the transaction, wherein addr_a ' is a virtual address mapped by a virtual address generator, forms an anonymous transaction T (addr_a, addr_a '), and a relay route collects the transaction asset evidence and locks the transaction. Step3, anchoring the asset by the relay chain, verifying the legitimacy of transaction information of both sides, applying for unlocking the asset by the relay chain by the receiving direction, completing the transaction, and recording the transaction by the relay chain, wherein the specific steps of Step3 are as follows: step3.1. relay routing gathers identity credentials and SPV transaction credentials from both parties to the transaction. Step3.2R-Chain verifies whether the asset T (addr_a, addr_a') satisfies the transaction, and if not, aborts the transaction and performs transaction rollback. If satisfied, the transaction is forwarded to the public account address addr_ra to form a new transaction Tra (T (×, addr_a'), addr_ra), and part Chaina of the transaction is completed. The part of the transaction of Step3.4: chainb is transferred from the public account address addr_Rb of the relay chain to the destination address addr_b ', then the unlocking transaction is transferred to addr_b by the relay route control, so as to form a new transaction Trb (addr_b', addr_b), at the moment, the two parties of the transaction are completed in the asset exchange, and the relay chain records the transaction result. And Step4, tracing