How (and Why) to Obfuscate Source Code

To obfuscate source code is the process of deliberately complicating code in ways that make it difficult or impossible for humans to understand, all without impacting the program’s output.

Programmers obfuscate source code to prevent it from being stolen, make it more difficult to tamper with, and to secure valuable information about the function of the code.

Unlike encryption, obfuscation only makes data unintelligible to humans. Since the data remains machine-readable to obfuscate source code protects the code from cybercriminals without adding extra steps like de-encryption that may slow down the program’s run time. 

In the competitive world of technology-based startups, intellectual property is often the highest-value asset a company owns. To obfuscate source code is an essential step to protecting your IP from being stolen by competitors.

Why Is Source Code So Hard to Protect?

Typically, valuable data and information is protected by restricting access.

For example, sensitive client files are kept secure in password-protected, encrypted accounts that are difficult or impossible for criminals to breach.

However, source code is visible to anyone using a program, so access prevention methods can’t be used to secure the code or any information stored within it.

Instead, programmers can “disguise” the code via obfuscation so that it looks nonsensical to humans but is still machine readable. This will prevent hackers from misusing the code while still allowing the program to run as designed.

Obfuscation software can be used to automatically apply different obfuscation methods to sections of code, or programmers can select portions of data and obfuscate them by hand.

How to Obfuscate Source Code & Data

There are many different methods for obfuscating data. In order to strengthen code protections, programmers can mix and match different techniques throughout the code to make it even more difficult for hackers to read.

Below we’ve outlined some of the more common techniques for effectively obfuscating data.

1. Alternate Code Forms

Translate short sections of the code into different forms throughout the program to make deciphering it more difficult without affecting run time.

For example, you can translate parts of your code to binary language, or replace a function with a table lookup of all possible values that the function might produce.

2. Change Up Data Storage Methods

Make your data more difficult to read by essentially “hiding” your data using different memory types and locations. Alternate between storing variables locally and globally to conceal how the variables work together. 

You can also randomize the addresses at which parts of code are located to create an additional level of confusion and make the code more difficult to read.

3. Randomize Aggregation Patterns

Another way to confuse hackers is by packaging your data in random sizes. For example, you might break arrays into an unnecessarily high number of sub-arrays to confuse any reverse engineering attempts.

4. Encrypt Strings

Though encryption isn’t an effective method for protecting your entire source code, you can use encryption as part of the obfuscation process without slowing the program.

Select individual keys, code strings, and other pieces of information to encrypt in order to create hacker “blind spots” in the code.

5. Interrupt Code Flow

Add unnecessary statements or “dead code” to your program to make it difficult to figure out what parts of the code contain real data.

Dummy code can also be used to conceal the pathways by which program control is passed between sections of the codebase.

6. Remove Debug Data

Debugging information can be used by hackers to reverse engineer a program’s source code, so it’s wise to obfuscate debug information by changing line numbers and file names.

Alternatively, you can remove debug information from your program entirely.

7. Obfuscate Assembly Code 

Concentrate obfuscation efforts on assembly code to make it especially difficult to reverse engineer.

Many programmers like to hide assembly code within other code in a sort of Russian nesting doll pattern called the “jump-in-the-middle” technique, which will prevent a disassembler from producing the correct outputs.

8. Renew Obfuscation Tactics Regularly

Employ a schedule of obfuscation tactic renewal and refresh the techniques you’ve used throughout the code.

Vary the pieces of information you’ve hidden and encrypted, and alternate between tactics in different portions of the code.

Using multiple tactics to thoroughly obfuscate source code and refreshing obfuscation regularly will protect your startup’s IP from the majority of potential hacks.

However, no security measure can guarantee your startup’s safety, which is why it’s important to complement your cybersecurity precautions with comprehensive tech insurance that should include cyber liability, tech errors & omissions, and commercial crime insurance in order to protect your tech startup from all possible forms of cyberattacks. 

By pairing your programmer’s attack prevention efforts with protection against a worst-case scenario, you’ll be able to keep your company safe no matter what happens.

To learn more about the policies that are right for your business, check out Embroker’s digital insurance platform. obfuscate