NelsonBigHead/RetroHook

x86/x64 Minimalistic header only VMT library.

RetroHook

RetroHook is an x86/x64, minimalistic header only library for placing hooks on virtual-functions. Ease and stealth is a priority, and future updates are inevitable. The library doesn't change any data of the address, bypassing data checks, and also doesn't require VirtualProtect to be called on the address. RetroHook was compiled with Microsoft Visual Studio 2022, but should be no problem building on any other compiler.

Requirements

• Default C++ Language Standard.
• Default C Language Standard.

x86 Usage

The following code below is an example of RetroHook compiled on x86 with MSVC 2022. Do keep in mind types such as uintptr_t and size_t are automatically deduced at compile-time.

#include <iostream>
#include <Windows.h>

#include "RetroHook.h"

class GameClass
{
public:
    virtual void DamagePlayer(int forAmount)
    {
        std::cout << "Damaged for " << forAmount << std::endl;
    }
};

using DamagePlayer_t = void(__stdcall*)(int);
DamagePlayer_t oDamagePlayer = nullptr;

void __stdcall DamagePlayerHk(int forAmount)
{
    return oDamagePlayer(999);
}

int main()
{
    GameClass* gameClass = new GameClass();

    // Create new VMT instance.
    RetroHook* vmt1 = new RetroHook(gameClass, 0, DamagePlayerHk);
    
    // Set hook originals.
    oDamagePlayer = (DamagePlayer_t)RetroHook_Util::GetVirtualAddr(gameClass, 0);

    // Set hook.
    if (vmt1->SetHook())
    {
        printf("[+] Hooked\n");
        gameClass->DamagePlayer(999);

        vmt1->RemoveHook();
        gameClass->DamagePlayer(123);
    }
    else
    {
        printf("[-] Failed to hook\n");
    }

    std::cin.get();
    return 0;
}

x64 Usage

The following code below is an example of RetroHook compiled on x64 with MSVC 2022. Do keep in mind types such as uintptr_t and size_t are automatically deduced at compile-time.

#include <iostream>
#include <Windows.h>

#include "RetroHook.h"

class GameClass
{
public:
    virtual void DamagePlayer(int forAmount)
    {
        std::cout << "Damaged for " << forAmount << std::endl;
    }
};

using DamagePlayer_t = void(__fastcall*)(void*, int);
DamagePlayer_t oDamagePlayer = nullptr;

void __fastcall DamagePlayerHk(void* ecx, int forAmount)
{
    return oDamagePlayer(ecx, 999);
}

int main()
{
    GameClass* gameClass = new GameClass();

    // Create new VMT instance.
    RetroHook* vmt1 = new RetroHook(gameClass, 0, DamagePlayerHk);
    
    // Set hook originals.
    oDamagePlayer = (DamagePlayer_t)RetroHook_Util::GetVirtualAddr(gameClass, 0);

    // Set hook.
    if (vmt1->SetHook())
    {
        printf("[+] Hooked\n");
        gameClass->DamagePlayer(123);

        vmt1->RemoveHook();
        gameClass->DamagePlayer(123);
    }
    else
    {
        printf("[-] Failed to hook\n");
    }

    std::cin.get();
    return 0;
}