Custom String pool

[br1337]

Hi guys

Nothing very special, but here is a little hook to use a custom StringPool based on your own DLL, allowing edit of MS Strings without stredit. However, you should use STR to extract the strings of the version in first place.

It may be useful when you want to change a string in the client, but dont have a unpacked and runnable version of the game.


Code is very self explanatory.

You must be registered to see links

Cheers,

 

[kokose1234]

could you post rest of the codes?

 

[Darter]

could you post rest of the codes?

Just do this instead, the posted code is weird.

#define ZXString		char*

bool Hook_StringPool__GetString(bool enable)
{
	//Log(__FUNCTION__ " %i\r\n", enable);

	typedef ZXString*(__fastcall* StringPool__GetString_t)(void* ecx, void* edx, ZXString* result, unsigned int nIdx, char formal);

	static auto StringPool__GetString =
		reinterpret_cast<StringPool__GetString_t>(0x00746750); //v95

	StringPool__GetString_t Hook = [](void* ecx, void* edx, ZXString* result, unsigned int nIdx, char formal) -> ZXString*
	{
		auto ret = StringPool__GetString(ecx, edx, result, nIdx, formal);

		if (nIdx == 2722) //Ranking URL
		{
			strcpy(*ret, "http://rebirth.ms");
		}

		//Log("StringPool__GetString: %s\r\n", *result);
		return ret;
	};

	return SetHook(enable, reinterpret_cast<void**>(&StringPool__GetString), Hook);
}

 

[Hoxia]

Just do this instead, the posted code is weird.

#define ZXString		char*

bool Hook_StringPool__GetString(bool enable)
{
	//Log(__FUNCTION__ " %i\r\n", enable);

	typedef ZXString*(__fastcall* StringPool__GetString_t)(void* ecx, void* edx, ZXString* result, unsigned int nIdx, char formal);

	static auto StringPool__GetString =
		reinterpret_cast<StringPool__GetString_t>(0x00746750); //v95

	StringPool__GetString_t Hook = [](void* ecx, void* edx, ZXString* result, unsigned int nIdx, char formal) -> ZXString*
	{
		auto ret = StringPool__GetString(ecx, edx, result, nIdx, formal);

		if (nIdx == 2722) //Ranking URL
		{
			strcpy(*ret, "http://rebirth.ms");
		}

		//Log("StringPool__GetString: %s\r\n", *result);
		return ret;
	};

	return SetHook(enable, reinterpret_cast<void**>(&StringPool__GetString), Hook);
}

Thx??????

 

[kokose1234]

is it ok to hook the function with detour?

 

[Darter]

is it ok to hook the function with detour?

yeah here

BOOL SetHook(BOOL bInstall, PVOID* ppvTarget, PVOID pvDetour)
{
	if (DetourTransactionBegin() != NO_ERROR)
		return FALSE;
	
	auto tid = GetCurrentThread();

	if (DetourUpdateThread(tid) == NO_ERROR)
	{
		auto func = bInstall ? DetourAttach : DetourDetach;

		if (func(ppvTarget, pvDetour) == NO_ERROR)
		{
			if (DetourTransactionCommit() == NO_ERROR)			
				return TRUE;			
		}
	}

	DetourTransactionAbort();
	return FALSE;
}

----------------------------------------------------------

You can also change StringPool entries without hooking by just changing the pointers of the char** StringPool::ms_aString but you gotta encode the new entry

 

[StoryMS]

Apply to 083？

 

[Feras]

Apply to 083？

Both methods work for v83 - I use something similar to Darter's and it works perfectly (I recommend his method cuz you only need to change one function).

BTW stringpool edits like this work fine if you just want the client's functions to retrieve strings of your choosing, but if for some reason you write your own functions that call the Stringpool methods within them, you might run into some issues since ZXString objects are actually members of a larger class which IDA doesn't tell you about (you might find pseudocode like ZXString<char>* v2 = this; ZXString<char>::_Release(v2 - 0xC); which proves this).

You'd need proper handling of this unnamed class by looking at the memory layout of zxstrings (or just use char* and wchar_t* when possible).

 

[CEO1]

Hi guys

Nothing very special, but here is a little hook to use a custom StringPool based on your own DLL, allowing edit of MS Strings without stredit. However, you should use STR to extract the strings of the version in first place.

It may be useful when you want to change a string in the client, but dont have a unpacked and runnable version of the game.


Code is very self explanatory.

You must be registered to see links

Cheers,

hey, how to compile this in C++.

Just do this instead, the posted code is weird.

#define ZXString        char*

bool Hook_StringPool__GetString(bool enable)
{
    //Log(__FUNCTION__ " %i\r\n", enable);

    typedef ZXString*(__fastcall* StringPool__GetString_t)(void* ecx, void* edx, ZXString* result, unsigned int nIdx, char formal);

    static auto StringPool__GetString =
        reinterpret_cast<StringPool__GetString_t>(0x00746750); //v95

    StringPool__GetString_t Hook = [](void* ecx, void* edx, ZXString* result, unsigned int nIdx, char formal) -> ZXString*
    {
        auto ret = StringPool__GetString(ecx, edx, result, nIdx, formal);

        if (nIdx == 2722) //Ranking URL
        {
            strcpy(*ret, "http://rebirth.ms");
        }

        //Log("StringPool__GetString: %s\r\n", *result);
        return ret;
    };

    return SetHook(enable, reinterpret_cast<void**>(&StringPool__GetString), Hook);
}

how to use your code my friend?

 

[knc1226]

How do i use it?
Do I need to have adresses of getstring?

 

[shavit]

suck a fat penis