Enabling Secure Boot Functionality by Using Physical Unclonable Functions

A firmware encryption for embedded devices can prevent the firmware from being read out to clone the device to a counterfeited one or to steal the intellectual property of the software developer. Also the integrity is ensured to hinder an attacker from manipulating the firmware to a malicious one. In this work, a cryptographic concept to implement a Secure Boot functionality using the intrinsic properties of a specific hardware device is shown. After describing the Physical Unclonable Function and the cipher used for the implementation, the key generation algorithm is explained. Further, the function of the crypto-module inside the system architecture and the secure boot sequence are described.