Il2CppDumper: il2cpp.h is not compatible with Ghidra

Though Il2CppDumper has the ability to label methods and parameters in Ghidra via the ghidra_with_struct.py script, this does not work if the types from il2cpp.h are not first imported, and that does not currently work. Relevant notes are in:

• #287: il2cpp.h does not include necessary primitive types, includes Ghidra-unsupported C+±style inheritance
• #366: ghidra_with_struct.py doesn’t work without il2cpp.h types defined prior to running
• #371: PR (with discussion) for these issues modified il2cpp.h generation rather than ghidra scripts, potentially negatively impacting IDA compatibility (and ruining inheritance). See comment by @Perfare.

Current (non-working) workflows:

1. Import il2cpp executable into ghidra (analysis is not needed)
2. Run script ghidra_with_struct.py without having imported il2cpp.h: this results in many errors of the type

   Could not identify type Il2CppType*(parsed as 'Il2CppType *')
   

   and

   Warning: Unable to parse
   void Blur__OnDisable (Blur_o* __this, const MethodInfo* method)
   Attempting to modify...
   Warning: also unable to parse
   void Blur__OnDisable (Blur_o* __thisext, const MethodInfo* method)
   Skipping.
   

Or:

1. Import il2cpp executable into ghidra (analysis is not needed)
2. File->Parse C Source…, then Clear (pencil eraser), Save As->il2cpp.h.prf, then add il2cpp.h and “Parse to Program”: this results in an error similar to:

   2021-03-30 17:11:08 INFO  (CParserTask$3) Parse Errors: C Parser:  Encountered errors during parse. 
        in /[redacted]/il2cpp.h near line -1
        near token: null
        Last Valid Datatype: Il2CppClass * *
        Check around CParserPlugin.out around line: 62
   

   (and at least in the case of the program I’m testing this on, line 62 is the first declaration of type uint32_t)

Unfortunately, then, at this time ghidra_with_struct.py doesn’t appear to be adding any information more than ghidra.py.

I’m hoping these two issues (missing primitives and inheritance) can be worked around with a ghidra scripting solution, probably with edits to ghidra_with_struct.py.

Question for @Perfare: Is this still worthwhile if it means losing obvious inheritance (in ghidra only)? Since ghidra is only supporting C types, I don’t imagine we’d be losing anything meaningful, but am happy to discuss.

I’ll begin working on a scripted solution for ghidra and add a PR when there’s something usable.