Security Through Amnesia: A Software-Based Solution to the Cold Boot Attack on Disk Encryption

Disk encryption has become an important security measure for a multitude of clients, including governments, corporations, activists, security-conscious professionals, and privacy-conscious individuals. Unfortunately, recent research has discovered an effective side channel attack against any disk mounted by a running machine\cite{princetonattack}. This attack, known as the cold boot attack, is effective against any mounted volume using state-of-the-art disk encryption, is relatively simple to perform for an attacker with even rudimentary technical knowledge and training, and is applicable to exactly the scenario against which disk encryption is primarily supposed to defend: an adversary with physical access. To our knowledge, no effective software-based countermeasure to this attack supporting multiple encryption keys has yet been articulated in the literature. Moreover, since no proposed solution has been implemented in publicly available software, all general-purpose machines using disk encryption remain vulnerable. We present Loop-Amnesia, a kernel-based disk encryption mechanism implementing a novel technique to eliminate vulnerability to the cold boot attack. We offer theoretical justification of Loop-Amnesia's invulnerability to the attack, verify that our implementation is not vulnerable in practice, and present measurements showing our impact on I/O accesses to the encrypted disk is limited to a slowdown of approximately 2x. Loop-Amnesia is written for x86-64, but our technique is applicable to other register-based architectures. We base our work on loop-AES, a state-of-the-art open source disk encryption package for Linux.Comment: 13 pages, 4 figure

A Tamper and Leakage Resilient von Neumann Architecture

We present a universal framework for tamper and leakage resilient computation on a von Neumann Random Access Architecture (RAM in short). The RAM has one CPU that accesses a storage, which we call the disk. The disk is subject to leakage and tampering. So is the bus connecting the CPU to the disk. We assume that the CPU is leakage and tamper-free. For a fixed value of the security parameter, the CPU has constant size. Therefore the code of the program to be executed is stored on the disk, i.e., we consider a von Neumann architecture. The most prominent consequence of this is that the code of the program executed will be subject to tampering. We construct a compiler for this architecture which transforms any keyed primitive into a RAM program where the key is encoded and stored on the disk along with the program to evaluate the primitive on that key. Our compiler only assumes the existence of a so-called continuous non-malleable code, and it only needs black-box access to such a code. No further (cryptographic) assumptions are needed. This in particular means that given an information theoretic code, the overall construction is information theoretic secure. Although it is required that the CPU is tamper and leakage proof, its design is independent of the actual primitive being computed and its internal storage is non-persistent, i.e., all secret registers are reset between invocations. Hence, our result can be interpreted as reducing the problem of shielding arbitrary complex computations to protecting a single, simple yet universal component

Micro-CernVM: Slashing the Cost of Building and Deploying Virtual Machines

The traditional virtual machine building and and deployment process is centered around the virtual machine hard disk image. The packages comprising the VM operating system are carefully selected, hard disk images are built for a variety of different hypervisors, and images have to be distributed and decompressed in order to instantiate a virtual machine. Within the HEP community, the CernVM File System has been established in order to decouple the distribution from the experiment software from the building and distribution of the VM hard disk images. We show how to get rid of such pre-built hard disk images altogether. Due to the high requirements on POSIX compliance imposed by HEP application software, CernVM-FS can also be used to host and boot a Linux operating system. This allows the use of a tiny bootable CD image that comprises only a Linux kernel while the rest of the operating system is provided on demand by CernVM-FS. This approach speeds up the initial instantiation time and reduces virtual machine image sizes by an order of magnitude. Furthermore, security updates can be distributed instantaneously through CernVM-FS. By leveraging the fact that CernVM-FS is a versioning file system, a historic analysis environment can be easily re-spawned by selecting the corresponding CernVM-FS file system snapshot.Comment: Conference paper at the 2013 Computing in High Energy Physics (CHEP) Conference, Amsterda

Distributed Virtual Disk Storage System

Distributed Virtual Disk Storage System (DVDSS) is a reliable and fully decentralized storage system which is based on the concept of Distributed Storage and Virtual Disk. It is Client / Server architecture and utilizes all free space of desktop machines of a LAN for storage purposes. DVDSS converts all storage of computers on the LAN into a large disk, create a virtual disk and provide this disk to all users of the system. Users can store their data files and folders on this disk and they can retrieve their data whenever they need. DVDSS provides a transparent and reliable access to data. It also provides data consistency and data security. The recovery of data when a node fails is also provided by DVDSS. The objective of system is to combine the all storage space of a LAN and utilize it for storage of user's data in transparent and reliable manner. Keywords: Distributed Storage, Virtual Disk, Space Utilization, data recovery, data consistency

Can SDV technology be uUtilised in a smartphone to prevent forensic analysis?

Eliminating the opportunities to successfully acquire data from mobile devices is a critical security objective for certain organisations. In particular, Government agencies require assurance that classified data is secured against hostile forensic analysis. The Secure Systems Silicon Data Vault (SDV) is a hardware based data encryption and access control device that has been accredited by the Australian Government to secure classified information held on laptops and portable hard disk drives; hardware is recognised as a superior trusted platform to implement security mechanisms. The SDV’s 128bit Advanced Encryption Standard (AES) cryptography, sophisticated key management & access controls and total disk encryption makes the SDV an extremely difficult device from which to acquire data and perform forensic analysis. With the increasing functionality and storage capabilities of Smartphones strong security mechanisms are required by organisations that may hold sensitive data on these devices. Software based security applications exist for Smartphones that provide good security and severely impact the acquisition of data suitable for forensic analysis. If strong hardware based security can be integrated into a Smartphone, forensic analysis could be further constrained. This paper considers the feasibility of implementing the SDV technology into a Palm Treo. An overview of the SDV is given and six security design principles are enumerated. Implementation of the six design principles ensure the SDV provides strong security. The Treo architecture is reviewed and the concept of operation enumerated. The challenges with respect to implementing a Smartphone SDV that is conformant with the security design principles are discussed. Possible Smartphone SDV conceptual designs are presented. The concept of operation, implementation issues and conformance of each conceptual design to the SDV security design principles are discussed