Band-S: Secure Band to Evade Cram Attacks to Queuing Disciplines for Ethernet-based In-Vehicle Networks

To satisfy the growing network bandwidth requirement of data-intensive automotive applications (e.g., autonomous driving), Ethernet is recently employed as the backbone of in-vehicle networks. Besides its high bandwidth, Ethernet-based systems require a much more complex software architecture than conventional networks (e.g., controller area network), leading to a system prone to unknown security vulnerabilities. This study reveals one of such attacks that obstruct safety-critical data flows between networked computers. In this attack, malicious applications generate garbage packets that are crammed into Linux transmit queues, blocking other important outgoing network packets. As a solution to this cram attack, we reserve a hidden transmit queue that can be used only by authorized applications through the trusted execution environment (TEE) of recent automotive application processors. For the evaluation, SOME/IP-based systems are implemented based on OP-TEE (an open source TEE), which successfully demonstrates our solution.