Some Java Obfuscator

A modified version of cheatbreaker-obf to test out some ideas I had

Features

Native obfuscators shouldn't be used for production

• StripTransformer
  • Strips debug information from classes, methods and fields
• ChecksumTransformer
  • Inserts block of code inside configurable class which will check if the target method is modified, uses modified asm to check constant pool and method bytecode
• InlinerTransformer (Disabled)
  • Tries to inline methods, does need massive improvements
• VariableTransformer
  • Just converted local variables to java.lang.Object[]
• ConstantPoolTransformer (Unstable)
  • Uses native method to modify constant pool and applies some simple number obfuscation
  • Uses basic xor encryption which shows the key it would be best to change it
• CodeHiderTransformer (Unstable)
  • Uses natives to hide method bytecode from the code attribute
• PackerTransformer
  • Packs classes into a single file which are loaded afterwards
• ToStringTransformer
  • Saw something cool in a source obfuscator and decided to implement it, converts strins to new Object() { toString... return "String" }.toString()
• ExceptionTransformer
  • Turns local storing to storing of exception objects

Disclaimers

• CodeHider
  • won't go over exceptions
  • skips methodhandle and class ldc
  • skips synthetic methods
  • breaks on classes with generated methods
  • can break randomly due to constant pool not being updated when generating bytes

Usage

You use the obfuscator by creating a config file much like the one provided and parsing it through command line

java -jar obfuscator.jar --config config.yml

Screenshots

String Obfuscation

Variable Obfuscation

Inliner Obfuscation

Checksum Obfuscation

ConstantPool Obfuscation (Unstable)

Packer Obfuscation

Code Hider Obfuscation (Unstable)

Exception Obfuscation

Credits

• cheatbreaker-obf for base
• most of utils methods aren't mine
• yaml classes for config stolen from bukkit