Design And Implementation Of Smart Contrct And Bitcoin Analysis System Based On Semantic Analisis

With the rapid development of blockchain,it gradually reflects a wide range of influence in various industries around the world.Since Bitcoin emerged as the carrier of blockchain.Blockchain has been widely valued and applied in many fields.Bitcoin and Ethereum are the most successful cases of blockchain.Ethereum users publish information in Ethereum by publishing smart contracts running on Ethereum virtual machine.In addition to completing transactions,bitcoin can also publish and disseminate information through specific fields in block.The release of vulnerable smart contracts and the spread of unsafe information on the chain cause the property loss of users and the ecological insecurity of the blockchain.Therefore,the analysis of smart contract vulnerabilities and information on the bitcoin chain has practical needs.This thesis analyzes the types and principles of loopholes in Ethereum smart contract,investigates the common strategies of contract loophole scanning,focuses on the stain scanning technology,and summarizes the types of vulnerabilities in the contract and their corresponding code characteristics.At the same time,based on the investigation of bitcoin data structure,this thesis studies the principle of information transmission on the bitcoin chain,obtains the information transmitted on the bitcoin by semantic analysis of the updated bitcoin information on the chain,and classifies it based on LSTM(long-term and short-term memory model).Based on the above semantic analysis technology,this thesis analyzes,designs and implements the Ethereum smart contract and bitcoin information analysis system.Based on Django Vue.js The framework builds a web service to provide semantic information query and analysis of Ethereum smart contract.The Scrapy framework is used to complete the real-time crawling of the Ethereum smart contract information,and the bitcoin node Bcoin is built to obtain the latest information on the bitcoin chain and analyze it,and then the semantic information is classified by LSTM(long-term and short-term memory model).In addition,the functional and non-functional tests of the system are carried out.In the aspect of function test,a variety of smart contract vulnerabilities can be hit by the contract audit function of the system,and the accuracy of bitcoin information classification is tested.Finally,the non-functional test of the system is carried out,including security test and accuracy test.These tests ensure the safety of the system function and provide high quality service.