Secure communication in microcomputer bus systems for embedded devices

The protection of the microcomputer bus system in embedded devices is essential to prevent eavesdropping and the growing number of todays hardware hacking attacks. This contribution presents a hardware solution to ensure microcomputer bus systems via the Tree Parity Machine Rekeying Architecture (TPMRA). For this purpose a scalable TPMRA IP-core is designed and implemented in order to meet adaptability, low cost terms and variable bus performance requirements. It allows the authentication of different bus participants as well as the encryption of chip-to-chip buses from a single primitive. The solution is transparent and easy applicable to an arbitrary microcomputer bus system for embedded devices on the market. A proof of concept implementation shows the applicability of the TPMRA in the standardized Advanced Microprocessor Bus Architecture (AMBA) by implementing the IP-core extension into the peripheral AMBA bus-to-bus interface. It will be shown that the proposed solution is latency free and can be easy implemented into the AMBA bus interface bridge in order to protect the ARM bus system with a low hardware overhead considering all AMBA bus features.