DNSGreen: A Comprehensive Defense System Against Bounce-Style DNS DDoS Attacks With P4

DNS recursive resolver plays the role of intermediary agent in domain name query service, making it easy to observe various DNS flooding attack behaviors. The programmable data plane has promoted innovation in in-band attack detection, but previous work has not concentrated on DNS services, and there are concerns with mistakenly killing benign traffic and low classification accuracy. In this paper, we propose DNSGreen, a comprehensive defense system against bounce-style DNS DDoS attacks in the programmable data plane. DNSGreen discusses flow and packet characteristics under anomalous behavior, employing a “flow-detection and packet-filtering” pattern to ensure effective defense while allowing benign traffic to pass through as much as possible. Furthermore, DNSGreen designs a whitelist collection module, which eliminates the need to inspect trusted streams in subsequent filtering and thereby reducing the occurrence of false positives. Finally, DNSGreen improves the allocation method of the statistical structure to enhance the accuracy of system alarms. We deploy DNSGreen on BMv2 switches and conduct tests in three attack scenarios, demonstrating that DNSGreen safeguards normal users with excellentF0:5score while filtering attack traffic.