At the 2014 USENIX Security Symposium in San Diego, Ca. this week, computer security researchers described a way to make it easier for users – and developers of new apps to plug into the Android Linux platform's security enhancements.
The researchers from from North Carolina State University and the Technical University of Darmstadt, Germnay said in a paper they presented that they have developed a modification to the core Android operating system that allows developers and users to plug in new security enhancements.
The new Android Security Modules (ASM) framework (Figure below ) they described aims to eliminate the bottleneck that prevents developers and users from taking advantage of new security tools.
“The ASM framework allows users to implement these new extensions without overhauling their firmware,” Enck says. “The framework is available now for security enthusiasts. But for widespread adoption, either Google or one of the Android phone manufacturers will need to adopt the framework and incorporate it into the OS.”
The ASM framework allows the creation of custom security control modules that better protect phones owned by consumers and businesses. The custom security modules receive “callbacks” for every security-sensitive operation in the Android OS. In this context, a callback means that Android is contacting the security module to determine whether an operation should proceed.
“Our ASM framework can be used in various personal and enterprise scenarios. For instance, security modules can implement dual persona: i.e., enable users to securely use their smartphones and tablets at home and at work while strictly separating private and enterprise data,” says Enck.
“Security modules can also enhance consumer privacy. The framework provides callbacks that can filter, modify, or anonymize data before it is shared with third-party apps, in order to protect personal information,” Enck says. “For instance consider an app like Whatsapp, which usually copies all your contacts to its server – which is not needed for it to function.” With ASM, the user can make sure Whatsapp only gets the information it really needs.
“In addition, we designed the framework to allow apps to create their own hooks, which could be enforced by the security module,” Enck says. “This increases flexibility for app developers and allows them to benefit from the security protections provided by the module.”
The researchers said they also went to great lengths to ensure that the ASM framework complies with the security guarantees Google and others make with app developers. For example, the framework can only make data access more restrictive.