reloc_transform_pass.hpp

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#pragma once
#include <obf/pass.hpp>
#include <obf/transform/operation.hpp>
#include <obf/transform/transform.hpp>
 
namespace theo::obf {
/// <summary>
/// this pass is like the next_inst_pass, however, relocations are encrypted
/// with transformations instead of the address of the next instruction. this
/// pass only runs at the instruction level and appends transformations into the
/// reloc_t object of the instruction symbol.
///
/// given the following code:
///
///     mov rax, &MessageBoxA
///
/// this pass will generate a random number of transformations to encrypt the
/// address of "MessageBoxA". These transformations will then be applied by
/// theodosius internally when resolving relocations.
///
///     mov rax, enc_MessageBoxA
///     xor rax, 0x389284324
///     add rax, 0x345332567
///     ror rax, 0x5353
/// </summary>
class reloc_transform_pass_t : public pass_t {
  explicit reloc_transform_pass_t() : pass_t(decomp::sym_type_t::instruction) {}
 
 public:
  static reloc_transform_pass_t* get();
  void run(decomp::symbol_t* sym);
 
 private:
  std::optional<recomp::reloc_t*> has_legit_reloc(decomp::symbol_t* sym);
};
}  // namespace theo::obf