Repackage-Proofing Android Apps

App repackaging has become a severe threat to theAndroid ecosystem. While various protection techniques, such as watermarking and repackaging detection, have been proposed, a defense that stops repackaged apps from working on user devices, i.e., repackage-proofing, is missing. We propose a technique that builds a reliable and stealthy repackage-proofing capability into Android apps. A large number of detection nodes are inserted into the original app without incurring much overhead, each is woven into the surrounding code to blur itself. Once repackaging is detected, a response node injects a failure in the form of delayed malfunctions, making it difficult to trace back. The response nodes and detection nodes form high-degree connections and communicate through stealthy communication channels, such that upon detection several of the many response nodes are selected stochastically to take actions, which further obfuscates and enhances the protection. We have built a prototype. The evaluation shows that the technique is effective and efficient.