SealFSv2: combining storage-based and ratcheting for tamper-evident logging

Abstract

Tamper-evident logging is paramount for forensic audits and accountability subsystems. It is based on a forward integrity model: upon intrusion, the attacker is not able to counterfeit the logging data generated before controlling the system. There are local and distributed solutions to this problem. Distributed solutions are suitable for common scenarios, albeit not appropriate for autonomous and loosely connected systems. Moreover, they can be complex and introduce new security issues. Traditional local tamper-evident logging systems use cryptographic ratchets. In previous works, we presented SealFS (from now on, SealFSv1), a system that follows a radically different approach for local tamper-evident logging based on keystream storage. In this paper, we present a new version, SealFSv2, which combines ratcheting and storage-based log anti-tamper protection. This new approach is flexible and enables the user to decide between complete theoretical security (like in SealFSv1) and partial linear degradation (like in a classical ratchet scheme), exchanging storage for computation with user-defined parameters to balance security and resource usage. We also describe an implementation of this scheme. This implementation, which showcases our approach, is an optimized evolution of the original Linux kernel module. It implements a stackable file system that enables transparent tamper-evident logging to all user space applications and provides instant deployability. Last, we present a complete performance evaluation of our current implementation and a fair performance comparison of the two opposite approaches for local tamper-evident logging (i.e., storage-based vs. ratcheting). This comparison suggests that, on current systems and general-purpose hardware, the storage-based approach and hybrid schemes perform better than the traditional ratchet approach.

Era of Sentinel Tech: Charting Hardware Security Landscapes Through Post-Silicon Innovation, Threat Mitigation and Future Trajectories

“…Attackers may have the ability to alter the historical logging data produced, Yet the tamper-evident system will identify any breach in integrity. Several instances of tamper-evident systems developed with various technologies and applications are discussed [25]- [27]. For instance, in anti-tampering coatings, the spray coating technique produced Fluorescence-Structural Colour Photonic Crystals (FSC-PCs) in a limited period by chemically joining fluorescent molecules to colloidal particles, a two-sided security card with different information displayed on each side depending on the amount of light.…”

Privacy and security issues surrounding vehicular Adhoc networks

“…They are designed to detect and indicate unauthorized changes. It contributes to the integrity of records [139]. If a party attempts to repudiate an action, tamper-evident logs can be used to demonstrate that the records have not been altered since the time of creation.…”