A method for verifying the integrity of cross-chain interactive data calculation results of blockchain

Abstract

The present invention discloses a method for verifying the integrity of the calculation results of cross-chain interactive data of blockchains. The verification method includes the following steps: the user of the access chain calculates the data participating in the operation obtained from the access chain according to the calculation request of the user of the main chain, performs homomorphic encryption on the data participating in the operation, and signs the encryption result, and sends the calculation result and the ciphertext and signature of the data participating in the operation to the access chain for storage; when the cross-chain interaction is completed, the access chain and the main chain respectively generate audit information for integrity verification and send it to the supervision chain, and the supervision chain verifies the integrity of the data processing results in the cross-chain interaction according to the received audit information. The present invention applies Paillier homomorphic encryption technology to process the data participating in the operation, and applies bilinear mapping technology to verify the integrity of the data participating in the operation, so as to realize the accurate verification of the integrity of the calculation results of the cross-chain interactive data, and at the same time ensure the correctness of the calculation results.

Description

Technical Field

[0001] The present invention relates to the field of cloud computing security and data auditing technology, and specifically to a method for verifying the integrity of blockchain cross-chain interactive data calculation results. Background Art

[0002] As the underlying technical solutions of blockchain are becoming more and more perfect, blockchain presents a broad prospect for application development. However, with the increase of storage and transaction throughput on blockchain, the storage and computing performance of blockchain, especially the storage and computing performance of single chain, has gradually become a bottleneck restricting the further development of blockchain network. In order to solve the performance problem in blockchain, the idea of ​​"multi-chain parallel" was proposed. The application of cross-chain technology for inter-chain interaction has realized the expansion of blockchain performance and broken through the performance bottleneck of single-chain architecture.

[0003] At present, the most discussed cross-chain solutions include notary method, relay, access chain, hash lock and distributed key control. Cross-chain technology can connect scattered blockchain islands and become a bridge to expand blockchain performance. Although the multi-chain architecture expands the performance of blockchain, it also brings new security issues. Existing technologies generally focus on the technical implementation of cross-chain, and lack in-depth research on issues such as data integrity verification in cross-chain interactions.

[0004] When a blockchain requests data calculation results from another blockchain, the chain requesting the data cannot determine the integrity of the calculation results. Therefore, it is necessary to design an integrity audit mechanism for cross-chain data calculation results to ensure that the calculation is reliable and secure during cross-chain interaction. Summary of the invention

[0005] In order to solve the above problems, the present invention proposes a method for verifying the integrity of blockchain cross-chain interactive data calculation results, and the verification method comprises the following steps:

[0006] Step 1: User A of the main chain obtains the current timestamp from the main chain, and sends the data calculation request and timestamp to user B of the access chain and the supervision chain;

[0007] Step 2: The custody chain generates some system parameters required for integrity verification and sends the system parameters to the main chain and custody chain;

[0008] Step 3: User B of the access chain obtains relevant data from the access chain according to the data calculation request of the main chain, calculates the data, encrypts and signs the data involved in the calculation with Paillier, and sends the calculation result, ciphertext, data signature processing result and other parameters back to the access chain for storage;

[0009] Step 4: The access chain passes the data calculation results and parameters for homomorphic encryption to the main chain;

[0010] Step 5: The main chain encrypts the data calculation results and sends the ciphertext to the supervision chain as integrity audit information;

[0011] Step 6: The access chain aggregates the data, generates audit information for integrity verification, and sends the audit information to the custody chain;

[0012] Step 7: The custody chain verifies the audit information according to the integrity verification method designed in the smart contract to determine the integrity of the cross-chain interaction data settlement results. If the audit information verification is passed, it means that the data provided by the access chain for auditing the cross-chain interaction data calculation results is complete. Otherwise, it means that the access chain does not provide complete data information for the audit of data calculation results. After the verification is completed, the custody chain sends the verification results to the main chain.

[0013] Preferably, in step 2, the chain of custody needs to generate some system parameters required for integrity verification, including: two multiplication cycle groups G, G 1 , the bilinear mapping relationship e:G×G→G 1 , random number υ∈G, hash function H:{0,1} * → G. The supervision chain sends the system parameters Ω = (e, G, υ, H) to the main chain and the access chain.

[0014] Preferably, in step 3, user B of the access chain calculates request R based on the data of user A of the main chain and performs the following operations:

[0015] Data calculation: Access chain user B obtains data for calculation from the access chain based on user A's calculation request. And perform calculations to obtain the result M, where k is the number of data involved in the calculation;

[0016] Homomorphic processing: data involved in the calculation Perform Paillier homomorphic encryption to obtain ciphertext The calculation formula is Among them, g is a random large prime number, T is the timestamp obtained from the main chain, N is the public key of the Paillier encryption algorithm, and the hash function Yes N 2 An integer set with elements.

[0017] Data signature: a collection of ciphertext Signature processing is performed, and the calculation formula is: Among them, name i It is c i The corresponding identifier, i is the index of the data involved in the operation,

[0018] Data transmission: Access chain user B sends the data calculation results M, N, h, Sent to the access chain storage, where Used to audit data integrity.

[0019] Preferably, in step 3, the access chain transfers the data calculation results across chains to the main chain for storage, and the operation process is as follows:

[0020] Privacy processing: The access chain performs Paillier homomorphic encryption on the calculation result M to be transmitted across the chain to generate the ciphertext C to prevent the plaintext calculation result M from leaking privacy or being tampered with during the cross-chain transmission process. The calculation formula is: C = g M ·h(T) N (modN 2 ).

[0021] Data transfer: The access chain transfers the ciphertext C to the main chain.

[0022] Preferably, in step 5, the main chain needs to generate audit information for this cross-chain interaction. This is used to determine the integrity of the data calculation results. To protect the privacy of the data processing results, the main chain performs homomorphic encryption on the data processing results M, and transmits the encrypted results C as design information to the supervision chain. The calculation formula is: C = g M ·h(T) N (modN 2 ).

[0023] Preferably, in step 6, the access chain needs to generate audit information for this cross-chain interaction to determine the integrity of the data calculation results. Aggregation is performed to generate audit information. The calculation formula is as follows: Access chain passes audit information to the custody chain

[0024] Preferably, in step 7, the custody chain receives the audit information C from the main chain and the audit information π from the access chain, and verifies the integrity of the calculation result of the cross-chain interaction data, and the operation is as follows:

[0025] Reproduction of calculation results: Reproduction of ciphertext according to data calculation request R The calculation process is used to obtain the calculation result δ of the ciphertext, and δ is compared with C to determine whether the calculation result is correct.

[0026] Integrity verification: Based on the received audit information π, the integrity is verified using the following equation. If the equation holds, it proves that the audit information passed from the receiving chain to the custody chain is complete.

[0027]

[0028] If all the above verifications are passed, it means that the calculation results of the cross-chain interaction data are complete.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The present invention provides a method for verifying the integrity of the calculation results of cross-chain interactive data in blockchains, introduces a regulatory blockchain to audit the cross-chain interaction process, and ensures that the decentralized characteristics of the blockchain system are not affected. The design uses Paillier homomorphic encryption technology, data signature technology, and bilinear mapping technology to process the calculation process and results, realizing the integrity audit of the data calculation results in the cross-chain interaction process, while ensuring the correctness of the calculation results. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of a model role of the present invention;

[0032] Figure 2 It is a schematic diagram of the system flow of the present invention;

[0033] Figure 3 It is a flow chart of the verification process of the present invention. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. To make the above-mentioned objects, features and advantages of the present invention more clearly understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0035] A method for verifying the integrity of cross-chain interactive data calculation results of blockchains, such as Figure 1 As shown in the figure, the system participants include three blockchains and two types of off-chain users. User A of the main chain is the initiator of the data calculation request. The main chain is responsible for receiving and storing data from the access chain. The access chain stores the data involved in the calculation. User B of the access chain performs data calculation according to the calculation request of the main chain user and transmits the result across the chain to the main chain. The supervision chain verifies the integrity of the calculation results of the cross-chain interactive data based on the audit information from the access chain. Figure 2 As shown, the method specifically comprises the following steps:

[0036] When user A of the main chain needs to obtain data calculation results from the access chain, he obtains the current timestamp T from the main chain and sends the data calculation request R and timestamp T to user B of the access chain and the supervision chain.

[0037] The system parameters required for integrity verification of the chain of custody include: two multiplication cyclic groups G, G 1 , the bilinear mapping relationship e:G×G→G 1, random number υ∈G, hash function H:{0,1} * → G. The supervision chain sends the system parameters Ω = (e, G, υ, H) to the main chain and the access chain.

[0038] User B who accesses the chain calculates request R based on user A's data and performs the following operations:

[0039] (1) Obtaining the data set for calculation from the access chain And perform data calculation to obtain the data calculation result M, where k is the number of data involved in the calculation;

[0040] (2) Generate parameters for Paillier homomorphic encryption: select three large prime numbers p, q, g, calculate the public key N = pq, and randomly select a hash function Indicates that there is N 2 An integer set with elements;

[0041] (3) Generate parameters for data signing: Random selection right calculate Among them, i∈[1,k], k is the number of data involved in the operation, is a private parameter visible only to user B;

[0042] (4) Data involved in the calculation Perform Paillier homomorphic encryption to obtain ciphertext The calculation formula is

[0043] (5) Ciphertext Signature, calculated as: Among them, name i It is c i The corresponding identifier, i is the index of the data involved in the operation;

[0044] (6) Access chain user B calculates the data results M, N, h, Send to access chain storage.

[0045] The access chain transmits the data calculation result M and N and h used for homomorphic encryption across chains to the main chain, and user A of the main chain can obtain the data calculation result M from the main chain.

[0046] After the cross-chain data interaction is completed, the access chain and the main chain need to generate audit information for integrity verification. The specific process is as follows: Figure 3 The main chain needs to generate audit information based on the stored data calculation result M, and the access chain needs to generate integrity verification audit information based on the ciphertext and signature of all data involved in the calculation.

[0047] The main chain uses the public key N and h to homomorphically encrypt the data calculation result M. The calculation formula is: C = g M ·h(T) N (modN 2 ). The main chain sends C into the custody chain as audit information.

[0048] The access chain is based on the stored Calculate the aggregation proof, the calculation formula is as follows: Access chain passes audit information to the custody chain

[0049] The custody chain receives the audit information C from the main chain and the audit information π from the access chain and performs the following operations:

[0050] (1) Reproduce the ciphertext based on the data calculation request R The calculation process is used to obtain the calculation result δ of the ciphertext, and δ is compared with C. If δ = C, the calculation result is considered correct.

[0051] (2) Use the following equation to verify integrity. If the equation holds, it proves that the audit information passed from the receiving chain to the custody chain is complete.

[0052]

[0053] If both (1) and (2) verifications are passed, it means that the calculation results of the cross-chain interaction data are complete.

[0054] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for verifying the integrity of cross-chain interactive data calculation results of blockchains, characterized in that: The following steps are involved: 1) User A of the main chain obtains the current timestamp from the main chain, and sends the data calculation request and timestamp to user B of the access chain and the supervision chain; 2) The custody chain generates the system parameters required for integrity verification and sends the system parameters to the main chain and access chain; 3) User B of the access chain obtains the data involved in the calculation from the access chain according to the data calculation request of the main chain, calculates the data involved in the calculation, performs Paillier homomorphic encryption on the data involved in the calculation to obtain the first ciphertext and signs it. User B sends the information including the calculation result, the first ciphertext and the signature processing result back to the access chain for storage; 4) The access chain passes the calculation result and the parameters used for homomorphic encryption to the main chain. The main chain encrypts the calculation result to obtain the second ciphertext and sends the second ciphertext to the supervision chain; 5) The access chain aggregates the data, generates audit information for integrity verification, and sends the audit information to the custody chain; 6) The supervision chain verifies the audit information according to the integrity verification method designed in the smart contract to determine the integrity of the cross-chain interaction data calculation results. If the audit information verification passes, it means that the data provided by the access chain for auditing the cross-chain interaction data calculation results is complete. Otherwise, it means that the access chain does not provide complete data information for the audit of data calculation results. After the verification is completed, the supervision chain sends the verification results to the main chain; In step 2), the system parameters Ω=(e,G,υ,H), where: G and G1 are two multiplication cyclic groups, e:G×G→G1 is a bilinear mapping relationship, the random number υ∈G, and the hash function H:{0,1} * →G; The implementation process of step 3) is as follows: First, user B obtains the data set involved in the calculation from the access chain according to user A's data calculation request. And calculate to get the calculation result M, where k is the number of data involved in the calculation; then, the data set involved in the calculation Perform Paillier homomorphic encryption to obtain the first ciphertext set The calculation formula is Among them, g is a random large prime number, T is the timestamp obtained from the main chain, N is the public key of the Paillier encryption algorithm, and the hash function h is: Yes N 2 elements of integer sets; then, for the first ciphertext set Signature processing is performed separately, and the calculation formula is: Among them, name i It is c i The corresponding identifier, i is the index of the data involved in the operation, is a randomly generated privacy parameter visible only to user B for auditing. is an integer set with N elements; finally, the calculation result M, the public key N, the hash function h, and the first ciphertext set Signature Collection Identifier Collection Sent to the access chain storage, where It is part of the audit information used for integrity audit; Step 4) The formula for obtaining the second ciphertext is: C = g M ·h(T) N (modN 2 ), M is the calculation result; Audit information in step 5) Among them, σ and Yes and The audit information generated after aggregation is calculated using the following formula: In step 6), First, the first ciphertext set is reproduced according to the data calculation request The calculation process is to obtain the calculation result δ, and compare δ with the second ciphertext C. If δ = C, it proves that the cross-chain data calculation result is correct; then, according to the received audit information π, the integrity is verified using the following equation. If the equation holds, it proves that the audit information passed from the receiving chain to the supervision chain is complete: If the judgment result is correct and the equation holds, it means that the calculation result of the cross-chain interaction data is complete.

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