You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
Theodosius/include/obf/passes/jcc_rewrite_pass.hpp

38 lines
1.0 KiB

#pragma once
#include <obf/pass.hpp>
namespace theo::obf {
/// <summary>
/// jcc rewrite pass which rewrites rip relative jcc's so that they are position
/// independent.
///
/// given the following code:
///
/// jnz label1
/// ; other code goes here
/// label1:
/// ; more code here
///
/// the jnz instruction will be rewritten so that the following code is
/// generated:
///
/// jnz br2
/// br1:
/// jmp [rip] ; address after this instruction contains the address
/// ; of the instruction after the jcc.
/// br2:
/// jmp [rip] ; address after this instruction contains the address of where
/// ; branch 2 is located.
///
/// its important to note that other passes will encrypt (transform) the address
/// of the next instruction. There is actually no jmp [rip] either, push/ret is
/// used.
/// </summary>
class jcc_rewrite_pass_t : public pass_t {
explicit jcc_rewrite_pass_t() : pass_t(decomp::sym_type_t::instruction){};
public:
static jcc_rewrite_pass_t* get();
void run(decomp::symbol_t* sym);
};
} // namespace theo::obf