Security Technology for Smartphones

Service functions are implemented on smartphones by storing on them personal information, network-operator information, corporate information, and so on. Most smartphones use an open source operating system (OS), and anyone can obtain the OS source code; consequently, smartphone users are exposed to the threat of receiving fraudulent information from people with malicious intent. Aimed at countering this threat, safe smartphones—on which information is protected by applying multiple technologies such as Secure Boot, Linux Security Module, and TrustZoneTM—are marketed. Secure Boot is a technology for detecting whether a boot program of a smartphone has been rewritten and protects network-operator information by making it impossible to start up programs modified by a third party. Linux Security Module prevents leaks of personal information by controlling access to information by any program installed after factory shipment and by stopping unauthorized access to that information. TrustZone ensures banking services are safe by separating program operating environments with hardware and by preventing unauthorized access to information by programs running on open source OSs. In this report, these technologies, namely, Secure Boot, Linux Security Module, and TrustZone, are described in detail.