Anti reverse engineering is the process or technique of preventing reverse engineering to be done on software code and applications. With the increasing significance of the application and their evolution in terms of sophistication, it is crucial that the developers employ measures that ensure that the crucial code as well as algorithms are protected from piracy.
Obfuscating code
The most used approach is often referred to as obfuscation Obfuscation is one of the most extensively used anti reverse engineering methods. This entails knowingly and deliberately writing code in a manner that does not easily lend itself to comprehension by a human being, while at the same time ensuring that the code’s functionality is not compromised. Actions such as renaming the variables and functions to unrecognizable names, stripping out comments, and placing irrelevant code in between confuse the program’s flow. While it does not fully stop reverse engineering, it does put a damper on it, at the very least.
Encrypt Key Parts of Code
One of the best anti tampering ways is to apply encryption on the sensitive part of an app code. By encapsulating the core logic/algorithms and than decrypting it during the runtime, reverse engineers cannot analyze the meaningful app behavior at compile/link-time. Selective encryption also has the advantage of reduced performance overheads as compared to full encryption. Main threat is in obtaining the decryption key, which are addressed by the features such as white-box cryptography – that include decryption procedure directly into the application.
Detect Debuggers and Emulators
Debuggers and emulators are the tools of choice when it comes to reverse engineers, as they are used to step through the apps code. Debugger/emulator detection code inside the app can deter the hackers to a large extent and thus, gradually slow them down. Some of them are time checks to look for the time taken to debug, checks for marks left by debugger in memory, and use of instructions that are not part of the standard instruction set if the CPU but are recognizable by emulators. It can also change its flow or exit when running in a reversed environment, and then the app will be able to make itself do this.
Runtime Integrity Checks
We can also proactively look for whether an app binary has been modified through integrity check during the runtime right before performing critical operations. This can be done through, for example, verifying the signatures of the app code in memory against a list of good values or performing consistent run-time checks on the expected behavior of the app. In the case that signs of modification are noticed the application can self destruct or do other protective measures. However, as this only raises an alarm when this screen has been tampered with rather than actually preventing this from happening, it is most effective when integrated with other anti-debugging and obfuscation techniques.
Server-side Logic and Checks
Replacing some sensitive app functionality and validation logic on a server side instead of the client side is an anti reverse technique. If hackers attempt to evade client-side measures through reverse-engineering, then the fundamental operations of the app shall still be protected on the server. This also enables the client-side code to be modified at runtime and prevent new hacking methods by just updating the corresponding code. Some of the useful examples include license key validation, cleaning of the data input from the end users, the protection of scores calculation in a game app through moving the code to the server.
Code Obfuscation Techniques
Some of the possible code obfuscation strategies which can be applied are as follows: – Lexical obfuscation – It converts code templates and variables into unrecognizable symbols and names. Data obfuscation process converts inline data such as string literals into encodings to make it hard to analyze. Increasing control obfuscation increases the number of non-functional conditional branches and loops in the original program. Layout obfuscation reorganizes code sequences, combines and splits functions, but does not change the code behavior. There is also a list of automated obfuscation tools that are also used to enhance protection as follows.
Protecting application access and its functions
It is the program flow analysis that becomes crucial to reverse engineering. It is therefore possible to design the app access controls and execution flows that would identify and report prohibited usage patterns. Forcing users to log in even for simplest operations, using strict role-based access patterns, checking the time line of activities for abnormal tendencies help to detect reverse engineer attacks. Another form of protection includes preventing unauthorized access to app file folders, encrypting them or tracking changes in the program configuration and resource files necessary for the application’s functioning.
Proactive monitoring methods
It is also crucial to prevent the attack landscape from being attacked over time when attempting to prevent reverse engineering. Gathering intelligence from open source discussion forums wherein hackers discuss tips, exploits and tools give insight into todays threats. The use of threat intelligence in the assessment of bad actors’ motives and capabilities when targeting our codes allows for specific and strategic defensive measures in return. Following forums for the purchase/sale of proprietary code with an eye for the illicit will result in prosecution of intellectual property crime. That kind of monitoring combined with the quick application of anti tampering measures is far stronger then simply having an app installed.
Conclusion
In the end of the blog, how to protect app from reverse engineering: Again, reverse engineering risks are likely to escalate as apps become even more imperative in commerce and everyday life. In isolation, each of obfuscation, integrity checks, server-side execution logic, and proactive threat monitoring are useful, but when used together, they are most effective at defending against reverse engineering and protecting code, user information, and app integrity.
