Biblio

Heterogeneous system-on-chip platforms with multiple processing cores are becoming increasingly common in safety-and security-critical embedded systems. To facilitate a logical isolation of physically connected on-chip components, internal communication links of such platforms are often equipped with dedicated access protection units. When performed manually, however, the configuration of these units can be both time-consuming and error-prone. To resolve this issue, we present a formal model and a corresponding design methodology that allows developers to specify access permissions and information flow requirements for embedded systems in a mostly platform-independent manner. As part of the methodology, the consistency between the permissions and the requirements is automatically verified and an extensible generation framework is used to transform the abstract permission declarations into configuration code for individual access protection units. We present a prototypical implementation of this approach and validate it by generating configuration code for the access protection unit of a commercially available multiprocessor system-on-chip.

Continuous development of Network-on-Chip (NoC) enables different types of applications to run efficiently in a Multiprocessor System-on-Chip (MP-SoC). Guaranteed service (GS) can be provided by circuit switching NoC and Best effort service (BES) can be provided by packet switching NoC. A hybrid NoC containing both packet and circuit switching, can provide both types of services to these different applications. But these different applications can be of different security levels and one application can interfere another application's timing characteristics during network transmission. Using this interference, a malicious application can extract secret information from higher security level flows (timing side channel) or two applications can communicate covertly violating the system's security policy (covert timing channel). We propose different mechanisms to protect hybrid routers from timing channel attacks. For design space exploration, we propose three timing channel secure hybrid routers viz. Separate Hybrid (SH), Combined with Separate interface Hybrid (CSH), and Combined Hybrid (CH) routers. Simulation results show that all three routers are secure from timing channel when compared to a conventional hybrid router. Synthesis results show that the area increments compared to a conventional hybrid router are only 7.63, 11.8, and 19.69 percent for SH, CSH, and CH routers respectively. Thus simulation and synthesis results prove the effectiveness of our proposed mechanisms with acceptable area overheads.

This work proposes a secure Network-on-Chip (NoC) approach, which enforces the encapsulation of sensitive traffic inside the asymmetrical security zones while using minimal and non-minimal paths. The NoC routing guarantees that the sensitive traffic communicates only through trusted nodes, which belong to a security zone. As the shape of the zones may change during operation, the sensitive traffic must be routed through low-risk paths. The experimental results show that this proposal can be an efficient and scalable alternative for enforcing the data protection inside a Multi-Processor System-on-Chip (MPSoC).