Secure and Authenticated Communication in Chip-Level Microcomputer Bus Systems with Tree Parity Machines

The protection of chip-level microcomputer bus systems in embedded devices is essential to prevent the growing number of hardware hacking attacks. This paper presents an authenticated key exchange and encryption solution in order to ensure chip-level microcomputer bus systems via the tree parity machine rekeying architecture (TPMRA). Due to this intention, a scalable TPMRA IP-core is designed and implemented in order to meet variable bus performance requirements. It allows the authentication of the 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 into the peripheral bus-to-bus interface (AHB-APB-bridge). It will be shown that the solution is latency free and can be used in order to protect the ARM bus system with a low hardware overhead considering all AMBA bus features.