A run-time API resolver for IL2CPP Unity.

Hi is there any way to get a private field from a class with IL2CPP Resolver? I am able to see it on DnSpy and Cheat Engine via .Net Info but after trying to get the class variables with IL2CPP Resolver via IL2CPP::Class::GetFields it dones't find any field m_uMaxLength is always zero. Thanks in advance.

Hey, first of all thank you for the library it is really good and easy to expand for your needs. Hoewer i am having an issue and i am not sure if it related to library or i am missing something, So i am trying to get the value from a Field of the game i am working on.

Here is the field i want to get, it is a member of ActorModel class (dnspy view)

Here is how i am trying to retreive it on my proyect:

int GetHp()
		{
			if (!MemoryMgr::IsValidPtr(this))
				return 0;

			auto m_pFieldOffset = IL2CPP::Class::Utils::GetFieldOffset(xorstr_("ActorModel"), xorstr_("get_Hp"));
			printf("Hp Offset %i || ptr %p\r\n", *reinterpret_cast<int8_t*>(reinterpret_cast<uintptr_t>(this + m_pFieldOffset), reinterpret_cast<uintptr_t>(this) + m_pFieldOffset);
			return *reinterpret_cast<int8_t*>(this + m_pFieldOffset);
		}

		int GetHpMax()
		{
			if (!MemoryMgr::IsValidPtr(this))
				return 0;

			auto m_pFieldOffset = IL2CPP::Class::Utils::GetFieldOffset(xorstr_("ActorModel"), xorstr_("get_HpMax"));
			printf("Hp Offset %i || ptr %p\r\n", *reinterpret_cast<int8_t*>(reinterpret_cast<uintptr_t>(this + m_pFieldOffset), reinterpret_cast<uintptr_t>(this) + m_pFieldOffset);
			return *reinterpret_cast<int8_t*>(this + m_pFieldOffset);
		}

Once i call it from any ActorModel it dones't make any exception, it just give me an invalid value like this:

Any help is appreciated, thank you!

IL2CPP::SystemTypeCache::Initializer::Add("CharacterManager");
IL2CPP::ResolveCall("CharacterManager::GetCharacterByFid") -> return zero

IL2CPP::Class::GetSystemType("CharacterManager") -> return address, class have in game
auto ooooo = IL2CPP::Class::Find("CharacterManager"); -> return address same as IL2CPP::Class::GetSystemType("CharacterManager") 

std::vector<Unity::il2cppMethodInfo*> methods;
IL2CPP::Class::FetchMethods(ooooo, &methods);

 for (auto method : methods)
{
 print(method->name); // return string GetCharacterByFid
}

public sealed class CharacterManager : Il2CppSystem.Object
{
public unsafe ActorModel GetCharacterByFid(int fid)
}

when my error?

IL2CPP::Data.Functions.m_pResolveFunction not zero

Hello,

First of all I would like to say sorry for my shitty C++ skills, I've been trying to run the example of getting the GameObject list but it seems I've stumbled upon pointer hell.

Also the Unity::il2cppArray type has no m_pArray, I'm thinking this has been replaced with m_pValues?

Other than that, the lib seems to be working fine, I've successfully printed methods of my PlayerManager class, but I have no idea how to call them. CClass has the CallMethod function, I got the method pointer through IL2CPP::Class::Utils::GetMethodPointer, but how do I get a CClass in the first place? I couldn't find a constructor and got stuck.

I would really appreciate some support, and thank you from the bottom of my heart for the nice lib!

Hi, its really not easy to know what to do with this source code, I tried Code::Block but failed, nothing worked.

Can you tell me what software did you use ? What compiler ? And how did you build the .dll ?

Thanks.

Hi,

1 - How to make it work in Code::Block ?

I created a new C++ Console project then in Project->Debug->Search Directories->Compiler, I clicked on Add and added the folder downloaded here containing all sources from IL2CPP_Resolver.

But I get errors like _undefined reference to `IL2CPP::String::New(char const)'_*

2 - How does IL2CPP_Resolver work ?

I'm not a C++ programmer so I don't understand how this works. Do we need to compile a .DLL and inject it ? Does it find the Unity game process automatically?

If you could answer these two questions, it would be great and I think usefull to others too. Thanks.

Hey there, this project is pretty amazing (great work on it!), I've used this on many il2cpp game then tried using it on BLOCKPOST (x86 il2cpp), and when calling the initialize function i get a crash. So i went to go change the calling convention from __fastcall to __cdecl and it seemed to fix the crash. But then i am not able to get the camera main or use any other functions. Any ideas?

Seems "UnityEngine.Camera::WorldToScreenPoint_Injected(UnityEngine.Vec" might be a better alternative, only requiring a Vector3 as a parameter. il2cpp_resolve_icall("UnityEngine.Camera::WorldToScreenPoint_Injected(UnityEngine.Vec"); would be used like UnityEngine.Camera::WorldToScreenPoint_Injected(this,UnityEngine.Vector3 m_vec);

Seems the resolve icall functionality supports slightly different names for method overloads.

I am currently rewriting my cheat for Devour using your library but i can't call a function without an access violation happening. Original C# code (using MelonLoader) :

NolanRankController NolanRank = UnityEngine.Object.FindObjectOfType<NolanRankController>();
NolanRank.SetRank(50);

New C++ code (using IL2CPP Resolver) :

void OnUpdate() {
    if (settings::spoof_level) {
        Unity::CGameObject* NolanBehaviour = Unity::Object::FindObjectOfType<Unity::CGameObject>("NolanRankController");
        NolanBehaviour->CallMethodSafe<void*>("SetRank", 50);
    }
}

The code crashes at void* GetMethodPointer(Unity::il2cppClass* m_pClass, const char* m_pMethodName, int m_iArgs), line 176 of Class.cpp :

Unity::il2cppMethodInfo* pMethod = reinterpret_cast<Unity::il2cppMethodInfo*(IL2CPP_CALLING_CONVENTION)(void*, const char*, int)>(Data.Functions.m_pClassGetMethodFromName)(m_pClass, m_pMethodName, m_iArgs);

Result : "Access violation in GameAssembly.dll when reading at 0xFFFFFFFF20000133."

What am i missing there ?

`template<typename T, typename N>
	struct il2cppDictionary : il2cppObject
	{
        void* buckets;
        void* entries;
        int32_t count;
        int32_t version;
        int32_t freeList;
        int32_t freeCount;
        void* comparer;
        void* keys;
        void* values;
        int32_t _syncRoot;
	};`

sorry not full, go sleeping