TB-Logger: Secure Vehicle Data Logging Method using Trusted Execution Environment and Blockchain

With the development of IT technologies, event data recorder (EDR) devices are now installed in modern vehicles to record and analyze vehicle-related events. As data recorded in EDRs began to be used as conclusive proof in courts, many researchers turned their to focus on developing methodologies that can protect data recorded in EDRs from data forgery attacks. In general, these existing methods generate verification values for EDR data by using a digital signature algorithm. However, these methods do not provide a way to protect the data stored in an EDR from data forgery attacks in the event of an emergency, such as a car accident, and it is not possible to properly create a verification value for the EDR data due to unexpected and sudden events like a power supply problem. Thus, in this paper, we propose TB-Logger, a novel method that protects EDR data even when there is an emergency situation. TB-Logger relies on the trusted execution environment (TEE) to protect EDR data from data forgery attacks, which ultimately result in data modification, reordering, and deletion. In addition, in the event of an emergency, TB-Logger utilizes a blockchain system to store verification values and publicly verify the data generated during the event. We evaluated the practicality of TB-Logger using two real vehicles: the Hyundai Avante CN7 and the Tesla Model 3. Through these tests, we confirmed that TB-Logger can generate verification values for EDR data without incurring any data loss.