  Security in TrustZone-enabled heterogeneous system-on-chip (SoC) is gaining
increasing attention for several years. Mainly because this type of SoC can be
found in more and more applications in servers or in the cloud. The inside-SoC
communication layer is one of the main element of heterogeneous SoC; indeed all
the data goes through it. Monitoring and controlling inside-SoC communications
enables to fend off attacks before system corruption. In this article, we study
the feasibility of encrypted data exchange between the secure software executed
in a trusted execution environment (TEE) and the secure logic part of an
heterogeneous SoC. Experiment are done with a Xilinx Zynq-7010 SoC and two
lightweight stream ciphers. We show that using lightweight stream ciphers is an
efficient solution without excessive overheads.
