A Study Of Application Running Mode And Security Techniques In Android

With the rapid development of Google's Android operating system,its security issues are catching more and more people's attention.Android provides users with many security mechanisms to ensure the property safety of the users,but ignores the protection of intellectual property of the android application developers.Many developers only use the android development tools to develop android applications,which can't resist the attacker's static analysis and dynamic debugging.It's easy for the attacker to get access to the code,so the application reinforcement system for Android applications to resist such attacks should be developed.At the same time,in order to improve the start and execution efficiency of the Android applications,Android has adopted Android RunTime(ART),a new application running model,as a substitute of the Dalvik running mode,but referring to the installation of the application and implementation process,the two modes are different.The previous Android applications reinforcement system could not adapt to the new ART mode.New Android applications reinforcement system is required to support both Dalvik mode and ART mode.This paper mainly studies the operation process and its difference between using the two android applications running mode,analyzes the android application runtime bytecode and machine code.Design and implement one android application of reinforcement system,which is compatible with Dalvik mode and ART mode at the same time.Applications that enforced by our reinforcement system should run on the different running modes and different android devices successfully.The main work in this paper is listed as follows:1.Analyze the Android application running modes.Mainly analyze the Dalvik and ART running mode,installation,start-up,implementation steps.What's more,analyze the difference between two running modes' bytecode file format.2.Design one android application reinforcement scheme.After using the new android application reinforcement scheme,applications can be run correctly in these two modes,ART mode and Dalvik mode.At the same time this new scheme will meet the requirement that resisting static analysis and dynamic debugging.3.Implement the android application reinforcement scheme.Design and implement the shell template based on application framework,which can hide the bytecode files.Design and implementation of the reinforcement system which generate optimized bytecode files respectively for Dalvik mode and ART mode.The optimized bytecode files can be dynamically loaded by Android system.Test results show that the applications handled by our reinforcement system can run successfully in either ART mode or Dalvik mode.