The simulation of Systems-on-Chip (SoC) is nowadays a hot topic because, beyond providing many debugging facilities, it allows the development of dedicated software before the hardware is available. Lowconsumption CPUs such as ARM play a central role in SoC. However, the effectiveness of simulation depends on the faithfulness of the simulator. To this effect, we propose here to prove significant parts of such a simulator, SimSoC. Basically, on one hand, we develop a Coq formal model of the ARM architecture while on the other hand, we consider a version of the simulator including components written in Compcert-C. Then we prove that the simulation of ARM operations, according to Compcert-C formal semantics, conforms to the expected formal model of ARM. Size issues are partly dealt with using automatic generation of significant parts of the Coq model and of SimSoC from the official textual definition of ARM. However, this is still a long-term project. We report here the current stage of our efforts and discuss in particular the use of Compcert-C in this framework.

No abstract

We develop an automated formal technique to specify and verify signed computation in cryptographic programs. In addition to new instructions, we introduce a type system to detect type errors in programs. A type inference algorithm is also provided to deduce types and instruction variants in cryptographic programs. In order to verify signed cryptographic C programs, we develop a translator from the GCC intermediate representation to our language. Using our technique, we have verified 82 C functions in cryptography libraries including NaCl, wolfSSL, bitcoin, OpenSSL, and BoringSSL. CCS CONCEPTS • Security and privacy → Logic and verification; • Theory of computation → Verification by model checking; • Software and its engineering → Formal software verification.

Traditional safety analysis of the avionics systems covers two aspects, i.e., the safety of the process and the safety of the current state. The mandatory analysis methodologies are the process safety analysis and Fault Tree Analysis (FTA), which meets the requirement of the Function Hazard Analysis (FHA). However, in the Integrated Modular Avionics (IMA) and Distributed Integrated Modular Avionics (DIMA), especially the networked IMA, the safety analysis method evolves into the Zachman framework analysis. Due to the increased complexity of the IMA and DIMA, the optimization algorithms should be developed. In this paper, based on the Cyber-Physical System (CPS), two optimization algorithms are revealed. One is the utility optimization algorithm subject to the safety requirement, another one is the direct optimization algorithm with the objective function of the safety. The proposed optimization schemes consolidate the methodology of the safety analysis and design of the avionics systems, especially in the IMA, DIMA, and the networked IMA.