Design And Development Of Blockchain System Based On Trusted Execution Environment

Blockchain is a publicly distributed ledger maintained by consensus among all participants.It allows the parties who do not trust the third party to conduct transactions safely without trusting the third party.It has the characteristics of decentralization and does not need to trust the third party.Once the information on the chain is recorded and agreed between nodes,it is considered to be untamperable.Because blockchain is decentralized and transparent,it can be used in different industries.However,in addition to some application scenarios that require the full openness and transparency of blockchain,in some scenarios,such as medical care and finance,there are privacy risks if the data information on the blockchain is completely exposed to anyone.Therefore,it is critical to address the issue of privacy protection on the blockchain.In order to solve the related privacy protection problems on blockchain,this paper designs and implements a blockchain system based on Trusteed Execution Environment(TEE).There are three innovative points in this paper:First,for the actual transaction scenario of the blockchain,this paper designs a function to initiate transactions based on the form of a digital envelope,which solves the privacy problem when users initiate transactions by encrypting user transaction content.Secondly,this paper designs a blockchain trusted node based on the Trusted Execution Environment(TEE)protected by hardware.The TEE environment adopted is the SGX provided by Intel.The contract is only decrypted and executed in Encalve provided by sgx,and stored in an external encryption,which solves the privacy problem of the contract state when the contract is executed and after it is completed.Finally,based on the consensus and considerations of trusted nodes,this paper proposes a group key agreement between trusted nodes to provide the keys required for encryption and decryption in the first two designs.The experimental results show that users can send private transactions and call privacy contracts through this blockchain system.The personal identities of both parties to the transaction and the status of the private transaction contract are invisible,which greatly protects the privacy of both parties and reduces the original privacy risks of the blockchain are eliminated.