Physical Unclonable Functions for Mobile Device Roots of Trust

Beginning with the release of the iPhone in 2007 and continuing with the increasing popularity of tablet computers, there has been an ever increasing desire to connect "unsecure" mobile devices to secure enterprise networks. Although several pieces of technology exist to meet this need, these devices lack a firm foundation upon which to build trust and security. This paper proposes development of Roots-of-Trust for mobile devices using Physical Unclonable Functions (PUF) and the ARM TrustZone trusted execution environment. Using these two basic technologies we propose building a Root of Trust for Storage (RTS), a Root of Trust for Integrity (RTI) and a Root of Trust for Verification (RTV). We will implement this capability on a selected mobile device platform without hardware modification. Because of the use of a PUF, our technology will make it nearly impossible to steal or clone a device's credentials. The new roost of trust will be used to implement a sample application that performs strong data-at-rest encryption and will make it impossible to decrypt the sample data if it is moved to a new device, or if the device's software is tampered with.