Research On The Blockchain Storage Proof Algorithm Based On The Oblivious Transfer Protocol

Blockchain storage proof has been developed for several years.It is mainly used to prove the existence of private data on blockchain.The prover provides the stored proof of the specified challenge in the fixed consensus interval,which exposes the construction of the original data proof to some extent.This paper proposes a block chain storage proof algorithm based on casual transport protocol,which satisfies zero knowledge and can prevent witch attack and external attack.First,the target data is split into linear file groups according to the default size and the grouping relation based on directed acyclic graph(DAG)is constructed for them.After the encryption result is generated,a binary Merkle tree is constructed for it.Finally,the binary Merckle root is used as storage proof,and the original data is published to the blockchain network.When the prover(storage node)generates the existence proof,according to the random challenge index initiated by the prover,the binary Merkle tree path generated after initialization and the ciphertext corresponding to the random challenge index are extracted as the data existence proof.In the process of challenge generation,the verifier(user)uses the original data fragments of the blockchain network to generate a random challenge set,and realizes the random challenge sending based on the RSA casual transmission protocol agreed with the prover to generate a challenge quantity that the verifier cannot judge.During the verification process,the local Merkle roots are constructed by traversing the random challenge set and merkle paths provided by the prover respectively,and the existence of the prover data is judged by comparing the local merkle roots with merkle roots on the blockchain.The resulting block chain-based stored proof algorithm(OT-Pos)has good zero-knowledge because the verifier cannot decide to reconstruct the binary Merle tree of the prover through the sequential challenge.The ciphertext connection based on directed Acyclic graph(DAG)prolongs the original data encryption time and shorts the ciphertext authentication time.The prover cannot generate the correct stored proof in a short time and can decode the specific grouping ciphertext under the condition of known partial precursor ciphertext.Experiments show that our algorithm can shorten the verification time and improve the efficiency of the system on the premise of preventing witch attacks.The index exceeds the existing block chain storage proof scheme,and it is a block chain storage proof algorithm with good comprehensive characteristics.