Research On The Security Of IOS System And Applications

With the development of Internet and computer technology, various kinds of mobile smart terminals gain more and more popularity, including smart phones, smart tablets, smart glasses and smart watches. Not only can users communicate and play games with smart terminals, but also process files and store sensitive data. As a result, smart terminals become the vessel of user’s privacy data, including address book,SMS, email, bank account, password and so on. What can not be neglected is that smart terminals bring users both convenience and security-related problems, such as privacy leak, virus, backdoor softwares etc.Nowdays the most popular mobile operating systems are Android and iOS. The latter one is developed by Apple Inc. and widely deployed on Apple’s mobile smart terminals. Thanks for Apple’s engineers and developers all over the world, iOS has captured a large amount of mobile market share. For one thing, attacks aimed at iOS have always been present, and for another, research towards iOS is considered to be difficult due to its property of close-source. Existing research results concerned with iOS are relatively few, most of which are related with security analysis, privacy leak and forensics.By focusing on research on the security of iOS operating system and applications,this dissertation studies previous work of iOS, then brings out innovative methods and technology for the security of iOS. Its main contribution includes:1. Thoroughly studies academic and industry research work on iOS system and se-curity, including system security, application security, digital forensics etc.2. Build a threat model of iOS by analysing the overall security structure of iOSdevice, including hardware security, system security and application security.3. Develop iOS device security evaluation system- iVerifier, which is proved to beable to evaluate the security of iOS hardware and the integrity of iOS system.4. Fully studies security problem concerned with iOS applications, including pri-vacy leak, user’s sensitive data and privacy being not fully protected due to de-velopers’ misuse of encryption primitives. Develop iOS application evaluationsystem- iCryptoTracer, which is proved to be able to trace misuses of encryptionin iOS applications, and evaluate the application accordingly.