区块链安全综述

区块链技术提供了一种在开放环境中存储数据、执行交易和处理业务的新方法，具有去中心化、防篡改等优势.从以比特币为代表的1.0时代，到以以太坊为代表的2.0时代，区块链技术已经对金融、物联网、供应链等行业产生了革命性的影响.然而由于技术和管理等方面的问题，目前区块链技术仍面临着很多安全挑战.首先，本文从信息安全、系统安全和隐私安全3个角度讨论了恶意信息攻击、51%攻击、智能合约攻击、拒绝服务攻击等8种区块链技术面临的攻击，分析了这些攻击的原理、执行过程和破坏性.接着，从以上3个角度详细讨论了智能矿池、Securify分析工具、混合技术、零知识证明等12种区块链安全保障技术，分析了这些安全保障技术的原理、执行过程、优点和局限性.最后，对区块链技术的未来研究方向进行了展望.

A survey on the security of blockchain

Blockchain technology,which has the advantages of decentralization and tamper-proofing,provides a new way to store information,execute transactions and handle business logic in an open environment.From the 1.0 era represented by Bitcoin to the 2.0 era represented by Ethereum,blockchain technology has revolutionized the finance,Internet of Things,supply chains and other industries.However,blockchain technology still faces many security challenges due to technical and management issues.Firstly,we discuss eight kinds of blockchain attacks in terms of information security,system security and privacy security,such as malicious information attacks,51% attacks,smart contract attacks,denial of service attacks,etc.,and analyze the principles,implementation processes and destructiveness of these attacks.Secondly,we discuss twelve blockchain security technologies from the above three perspectives,such as SmartPool,Securify analysis tool,mixing service and zero-knowledge proof,and analyze the principles,implementation processes,advantages and limitations of these technologies.Finally,we look forward into the future research directions of blockchain technology.