Smart Contract Firewall: Protecting the on-Chain Smart Contract Projects

The burgeoning landscape of blockchain technology has made the security of deployed smart contracts an imperative concern. While existing security measures excel in predeployment testing, they fall short in protecting smart contracts once they are deployed, leaving them susceptible to malicious attacks. In this paper, we propose a novel Smart Contract Firewall framework designed to bridge this security gap. Functioning as a dynamic gateway, the framework employs real-time transaction inspection through adaptable filtering rules, enabling the identification and rollback of malicious transactions as they occur. Our empirical analysis demonstrates the framework's efficacy in mitigating a majority of existing vulnerabilities in the deployed smart contracts. Although the added layer of security comes at a cost, we prove that the increased gas expenses could be limited to 30%-50% for most transactions. This trade-off, we argue, is a small price to pay for significantly enhanced security.