# A Framework to Quantify the Quality of Source Code Obfuscation
## 2 Background
### Source Code Obfuscator  
A source code obfuscator is a tool or software engineered to transform readable source code into a format that is challenging to comprehend and analyze yet maintains its original functionality. The main objective of an obfuscator is to safeguard intellectual property and bolster security by rendering reverse engineering, tampering, or unauthorized analysis more difficult. This goal is accomplished by employing various obfuscation techniques, including altering variable names, modifying code structure, scrambling control flow, and implementing encryption or encoding schemes. These alterations make the code appear complex and incomprehensible to humans, but the architecture can still interpret it as maintaining its original functionality. Obfuscators are extensively utilized in software development, particularly in applications where securing and protecting sensitive information is paramount. This tool is a crucial part of a developer's toolbox for safeguarding code against piracy, unauthorized modification, and exploitation of vulnerabilities. Stunnix C/C++ Obfuscator and Semantic Designs C-GCC4 Obfuscator enhance source code security by making C/C++ code difficult to comprehend and analyze. Stunnix obfuscates code by shuffling its structure, renaming variables, and altering data structures, thus retaining functionality while appearing unreadable. Semantic Designs retains the code's logic while adding complexity through excessive whitespace and newlines. Both tools protect intellectual property and prevent unauthorized access by making the source code hard to decipher. The Tigress obfuscation tool is a robust, flexible software program crafted to modify C programs. Tigress enhances security and resilience against reverse engineering. Tigress is recognized for its comprehensive range of obfuscation strategies, encompassing control flow and data obfuscation, code virtualization, and anti-debugging techniques. It can generate multiple versions of the same functionality, significantly complicating the task for attackers to grasp the program's logic or identify vulnerabilities. A notable feature of Tigress is its ability to create virtual machines within the code. Within a virtual machine, the original program logic is transformed into bytecode for execution, adding a complexity layer. This tool proves particularly valuable in protecting software's intellectual property, deterring tampering, and guarding against diverse forms of exploitation. Tigress is well-suited for various uses, from academic research to industrial software development, particularly in scenarios where enhancing C code security is paramount. Obfuscator LLVM is a notable open-source obfuscation tool that integrates with the LLVM compiler framework. This tool adds a layer of security and protection to the LLVM intermediate representation. Obfuscator LLVM is distinguishable for its ability to implement advanced obfuscation techniques at the compiler level, such as Control Flow Flattening, spurious control flow, and Instruction Substitution. These techniques thwart reverse engineering efforts by rendering the source code extremely difficult to analyze and comprehend. For instance, Control Flow Flattening obscures the execution path by transforming the program structure into a single, complex switch-case statement. Instruction Substitution enhances code complexity by swapping simple instructions with more intricate, semantically equivalent alternatives.