@ -11,6 +11,52 @@ both kernel and usermode projects. Since Theo inherits HMDM (highly modular driv
Since Theo is a jit linker, unexported symbols can be jit linked. Resolving such symbols is open ended and allows the programmer of this framework to handle how they want to resolve symbols. More on this later (check out example projects).
# RIP Relative Addressing
In order to allow for a routine to be scattered throughout a 64bit address space, RIP relative addressing must not be used. In order to facilitate this, a very special version
of clang-cl is used which can use `mcmodel=large`. This will generate instructions which do not use RIP relative addressing when referencing symbols outside of the routine in which the
instruction itself resides. The only exception to this is JCC instructions, (besides call) also known as branching instructions. Take this c++ code for an example:
```cpp
ObfuscateRoutine
extern "C" int ModuleEntry()
{
MessageBoxA(0, "Demo", "Hello From Obfuscated Routine!", 0);
UsermodeMutateDemo();
UsermodeNoObfuscation();
}
```
This c++ function, compiled by clang-cl with `mcmodel=large`, will generate a routine with the following instructions:
```nasm
0x00: ; void UsermodeNoObfuscation(void)
0x00: public ?UsermodeNoObfuscation@@YAXXZ
0x00: ?UsermodeNoObfuscation@@YAXXZ proc near ; CODE XREF: ModuleEntry+42↓p
The usage of the word obfuscation in this project is use to define any changes made to code, this includes code flow. `obfuscation::obfuscate`, a base class, which is inherited and expanded upon by `obfuscation::mutation`, obfuscates code flow by inserting `JMP [RIP+0x0]` instructions after every single instruction. This allows for a routine to be broken up into unique allocations of memory and thus provides more canvas room for creative ideas.