See the blog post explaining this project here: http://rammic.github.io/2015/07/28/hiding-secrets-in-android-apps/
This is a simple demonstration app to illustrate some of the methods used hide keys, passwords, or other sensitive information within an APK. This project doesn't aim to show how this SHOULD be done- rather, we want to how show the various techniques work as well as some of the more significant limitations.
There is simply no foolproof way to prohibit someone with an app's binaries from accessing sensitive information embedded within it. This is especially true with Android apps. Hiding and obfuscation techniques can only make the task reverse engineering task harder. The only surefire way to keep information safe from compromised is to not expose it- keep passwords, keys, etc. on a server you own and never put it into the app in the first place.
This project does not aim to address content DRM, encryption, encoding, etc. directly- all of which are relevant once the relevant key material has been successfully embedded and retrieved. Instead, this project will focus on key management techniques specifically.
It's easiest to just build a single platform variant if you want analyze the generated binaries:
gradle clean assembleX86Debug
Note that this project depends on the current Android NDK. Android Studio and Gradle builds will notify you of that the current NDK is deprecated:
Android plugin version 1.2.3 is not compatible with the NDK support. Please use the experimental plugin. or
Current NDK support is deprecated. Alternative will be provided in the future.
Builds should still work though despite the warning. See Issue #2 for more information.
If you have a novel key management/protection scheme that you'd like to see included, please feel free to open a pull request to include it.
This project is intended to be instructive and, as such, many of the examples will be implemented in an unnecessarily vulnerable or trivially broken manner. You should not depend on code or examples from this project alone if you decide to hide sensitive information within your app.
The MIT License (MIT)
Copyright (c) 2015- Apothesource, Inc.
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