Lightweight Security Enforcement on Android Platform

Google's Android platform has thrived in the smartphone market and has received a considerable amount of attention from mobile developers. Android's open platform encourages development of various applications and delivery systems, but this open source policy weakens dependability against various attacks. In this paper, we apply TOMOYO Linux, which provides MAC-based tools to Android to enforce security and solve the rooting problem. Because these security enforcement tools run at the kernel level, Android applications do not need to be modified. We evaluate the patched platform on an evaluation board. The results show that the performance overhead of file operations is trivial. Our platform also protects the system from various attacks that compromise the entire system by obtaining root privilege. And we propose the new design which dynamically applies security policy files when application is installed.