Biblio

Any technique to ensure memory safety requires knowledge of (a) precise array bounds and (b) the data types accessed by memory load/store and pointer move instructions (called, owners) in the program. While this information can be effectively derived by compiler-level approaches much of this information may be lost during the compilation process and become unavailable to binary-level tools. In this work we conduct the first detailed study on how accurately can this information be extracted or reconstructed by current state-of-the-art static reverse engineering (RE) platforms for binaries compiled with and without debug symbol information. Furthermore, it is also unclear how the imprecision in array bounds and instruction owner information that is obtained by the RE tools impacts the ability of techniques to detect illegal memory accesses at run-time. We study this issue by designing, building, and deploying a novel binary-level technique to assess the properties and effectiveness of the information provided by the static RE algorithms in the first stage to guide the run-time instrumentation to detect illegal memory accesses in the decoupled second stage. Our work explores the limitations and challenges for static binary analysis tools to develop accurate binary-level techniques to detect memory errors.

Anonymous Communication (AC) hides traffic patterns and protects message metadata from being leaked during message transmission. Many practical AC systems have been proposed aiming to reduce communication latency and support a large number of users. However, how to design AC systems which possess strong security property and at the same time achieve optimal performance (i.e., the lowest latency or highest horizontal scalability) has been a challenging problem. In this paper, we propose an ObliComm framework, which consists of six modular AC subroutines. We also present a strong security definition for AC, named oblivious communication, encompassing confidentiality, unobservability, and a new requirement sending-and-receiving operation hiding. The AC subroutines in ObliComm allow for modular construction of oblivious communication systems in different network topologies. All constructed systems satisfy oblivious communication definition and can be provably secure in the universal composability (UC) framework. Additionally, we model the relationship between the network topology and communication measurements by queuing theory, which enables the system's efficiency can be optimized and estimated by quantitative analysis and calculation. Through theoretical analyses and empirical experiments, we demonstrate the efficiency of our scheme and soundness of the queuing model.