C-FLAT: Control-FLow ATtestation for Embedded Systems Software

Remote attestation is a crucial security service particularly relevant to increasingly popular IoT (and other embedded) devices. It allows a trusted party (verifier) to learn the state of a remote, and potentially malware-infected, device (prover). Most existing approaches are static in nature and only check whether benign software is initially loaded on the prover. However, they are vulnerable to run-time attacks that hijack the application's control or data flow, e.g., via return-oriented programming or data-oriented exploits. As a concrete step towards more comprehensive run-time remote attestation, we present the design and implementation of Control- FLow ATtestation (C-FLAT) that enables remote attestation of an application's control-flow path, without requiring the source code. We describe a full prototype implementation of C-FLAT on Raspberry Pi using its ARM TrustZone hardware security extensions. We evaluate C-FLAT's performance using a real-world embedded (cyber-physical) application, and demonstrate its efficacy against control-flow hijacking attacks.Comment: Extended version of article to appear in CCS '16 Proceedings of the 23rd ACM Conference on Computer and Communications Securit

Privaros: A Framework for Privacy-Compliant Delivery Drones

We present Privaros, a framework to enforce privacy policies on drones. Privaros is designed for commercial delivery drones, such as the ones that will likely be used by Amazon Prime Air. Such drones visit a number of host airspaces, each of which may have different privacy requirements. Privaros provides an information flow control framework to enforce the policies of these hosts on the guest delivery drones. The mechanisms in Privaros are built on top of ROS, a middleware popular in many drone platforms. This paper presents the design and implementation of these mechanisms, describes how policies are specified, and shows that Privaros's policy specification can be integrated with India's Digital Sky portal. Our evaluation shows that a drone running Privaros can robustly enforce various privacy policies specified by hosts, and that its core mechanisms only marginally increase communication latency and power consumption

Middleware for Wireless Sensor Networks: An Outlook

In modern distributed computing, applications are rarely built directly atop operating system facilities, e.g., sockets. Higher-level middleware abstractions and systems are often employed to simplify the programmer’s chore or to achieve interoperability. In contrast, real-world wireless sensor network (WSN) applications are almost always developed by relying directly on the operating system. Why is this the case? Does it make sense to include a middleware layer in the design of WSNs? And, if so, is it the same kind of software system as in traditional distributed computing? What are the fundamental concepts, reasonable assumptions, and key criteria guiding its design? What are the main open research challenges, and the potential pitfalls? Most importantly, is it worth pursuing research in this field? This paper provides a (biased) answer to these and other research questions, preceded by a brief account on the state of the art in the field

Top of the Heap: Efficient Memory Error Protection for Many Heap Objects

Exploits against heap memory errors continue to be a major concern. Although many defenses have been proposed, heap data are not protected from attacks that exploit memory errors systematically. Research defenses focus on complete coverage of heap objects, often giving up on comprehensive memory safety protection and/or incurring high costs in performance overhead and memory usage. In this paper, we propose a solution for heap memory safety enforcement that aims to provide comprehensive protection from memory errors efficiently by protecting those heap objects whose accesses are provably safe from memory errors. Specifically, we present the Uriah system that statically validates spatial and type memory safety for heap objects, isolating compliant objects on a safe heap that enforces temporal type safety to prevent attacks on memory reuse. Using Uriah, 71.9% of heap allocation sites can be shown to produce objects (73% of allocations are found safe) that satisfy spatial and type safety, which are then isolated using Uriah's heap allocator from memory accesses via unsafe heap objects. Uriah only incurs 2.9% overhead and only uses 9.3% more memory on SPEC CPU2006 (C/C++) benchmarks, showing that many heap objects can be protected from all classes of memory errors efficiently

Tighter Integration of Drivers and Protocols in a AADL-based Code Generation Process

Model-based engineering provides an appealing frame- work for the precise modeling and analysis of embed- ded systems. Architecture Description Languages provide a clear and precise semantics to address multiple analy- sis dimensions: scheduling, fault, resource accounting, etc. This is completed by code generation tools that generate all required glue code to enable intercommunication between components and associated configuration mechanisms. The diversity of embedded targets requires extended con- figuration to support multiple devices, operating systems but also compilation toolchains. Yet, those are usually hard- wired in the code generation process. In this paper, we propose several patterns to support model- level configuration of the target, but also increased analysis capabilities in the context of the AADLv2