9.网络游戏逆向分析与漏洞攻防-游戏网络架构逆向分析-接管游戏连接服务器的操作

#include "pch.h"
#include "GameProc.h"
#include "extern_all.h"
 
// typedef bool(GameWinSock::* U)(char*, unsigned);
 
 
 
bool _OnConnect(HOOKREFS2) {
	/*
		根据虚函数表做HOOK的操作
		截取 ecx 获取 winsock 的值(指针)
	*/
	unsigned* vtable = (unsigned*)_EDX;
	//WinSock = (GameWinSock *)_ECX;
	/*
		联合体的特点是共用一个内存
		由于 GameWinSock::OnConnect 的 OnConnect函数是 GameWinSock类的成员函数
		直接 vtable[0x34 / 4] = (unsigned)&GameWinSock::OnConnect; 这样写语法不通过
		所以使用联合体，让语法通过
	*/
	union {
		unsigned value;
		bool(GameWinSock::* _proc)(char*, unsigned);
	} vproc;
 
	/*
		vproc._proc = &GameWinSock::OnConnect;  这一句是把我们自己写的调用connect函数的地址的出来
	*/ 
	vproc._proc = &GameWinSock::OnConnect; 
	/*
		InitClassProc函数里做的是给指针赋值的操作
		InitClassProc(&GameWinSock::_OnConnect, vtable[0x34/4]);这一句的意思是把
		GameWinSock类里的_OnConnect变量的值赋值成vtable[0x34/4]，这个 vtable[0x34/4] 是虚表里的函数
		vtable[0x34/4]是游戏中调用connect函数的函数地址，经过之前的分析调用connect是先调用了虚表中的
		一个函数，然后从这个函数中调用了connect函数
	*/
	InitClassProc(&GameWinSock::_OnConnect, vtable[0x34/4]);
	CString str;
	str.Format(L"===vtable：%X", vtable[0x34 / 4]);
	AfxMessageBox(str);
	DWORD oldPro,backProc;
	VirtualProtect(vtable, 0x100, PAGE_EXECUTE_READWRITE, &oldPro);
	vtable[0x34 / 4] = vproc.value;
	VirtualProtect(vtable, 0x100, oldPro, &backProc);
	return true;
}
 
GameProc::GameProc()
{
	hooker = new htd::hook::htdHook2();
	Init();
	InitInterface();
}
 
void GameProc::LoadBase()
{
	LoadLibraryA("fxnet2.dll");
}
 
void GameProc::Init()
{
}
 
 
 
void GameProc::InitInterface()
{
	LoadBase();
	MessageBoxA(0, "1", "1", MB_OK);
	hooker->SetHook((LPVOID)0x10617046, 0x1, _OnConnect, 0, true);
}

#pragma once
class GameWinSock
{
	typedef bool(GameWinSock::* PROC)(char*, unsigned);
public:
	static PROC _OnConnect;
	bool OnConnect(char* ip, unsigned port);
};
 

#include "pch.h"
#include "GameWinSock.h"
#include "extern_all.h"
 
GameWinSock::PROC GameWinSock::_OnConnect{};
// 这个函数拦截了游戏的连接
bool GameWinSock::OnConnect(char* ip, unsigned port)
{
    // this是ecx，HOOK的点已经有ecx了
    WinSock = this;
    MessageBoxA(0, ip, ip, MB_OK);
	bool b = (this->*_OnConnect)(ip, port);
	// 下方注释的代码时为了防止多次注入，导致虚函数地址不恢复问题导致死循环，通过一次性HOOK也能解决
	/*unsigned* vtable = (unsigned*)this;
	vtable = (unsigned*)vtable[0];
	union {
		unsigned value;
		bool(GameWinSock::* _proc)(char*, unsigned);
	} vproc;
	vproc._proc = _OnConnect;
	DWORD oldPro, backProc;
	VirtualProtect(vtable, 0x100, PAGE_EXECUTE_READWRITE, &oldPro);
	vtable[0x34 / 4] = vproc.value;
	VirtualProtect(vtable, 0x100, oldPro, &backProc);*/
 
    return b;
}

// htdMfcDll.cpp: 定义 DLL 的初始化例程。这是一个MFC的dll
//
 
#include "pch.h"
#include "framework.h"
#include "htdMfcDll.h"
#include "extern_all.h"
 
#ifdef _DEBUG
#define new DEBUG_NEW
#endif
 
// 注释掉下方宏，以入口点注入的方式注入
// #define WNDHOOK
#ifdef WNDHOOK
typedef struct htdDll
{
	HHOOK     keyHook;
	unsigned  KbdProc;
	unsigned  SetDll;
 
}*PHtdDll;
void htdSetDll(htdDll hDll);
htdDll mDll;
#endif
 
BEGIN_MESSAGE_MAP(ChtdMfcDllApp, CWinApp)
END_MESSAGE_MAP()
 
 
// ChtdMfcDllApp 构造
 
ChtdMfcDllApp::ChtdMfcDllApp()
{
	
}
 
ChtdMfcDllApp theApp;
ChtdMfcDllApp* PtheApp;
 
HHOOK keyHook;
LRESULT CALLBACK KeyCallBack(int nCode, WPARAM w, LPARAM l);
 
BOOL ChtdMfcDllApp::InitInstance()
{
	CWinApp::InitInstance();
	PtheApp = this;
#ifdef WNDHOOK
	mDll.KbdProc = (DWORD)(KeyCallBack);
	mDll.SetDll = 0;
#else
	keyHook = SetWindowsHook(WH_KEYBOARD, KeyCallBack);// 代码一开始，在这注册一个键盘事件的钩子
#endif
	PGameProc = new GameProc();
	return TRUE;
}
 
// 钩子处理事件
LRESULT CALLBACK KeyCallBack(int nCode, WPARAM w, LPARAM l)
{
 
	if (nCode == 0)
	{
		if ((l & (1 << 31)) == 0)
		{
			switch (w)
			{
			case VK_HOME:
 
				if (PtheApp->wndMain == NULL)
				{
 
					PtheApp->wndMain = new CUI();
					PtheApp->wndMain->Create(IDD_MAIN);
 
				}
 
				PtheApp->wndMain->ShowWindow(TRUE);
				break;
			}
		}
	}
	return CallNextHookEx(keyHook, nCode, w, l);
}
#ifdef WNDHOOK
void htdInit(htdDll* hDll)
{
	hDll->KbdProc = mDll.KbdProc;
	hDll->keyHook = mDll.keyHook;
	hDll->SetDll = mDll.SetDll;
}
 
void htdSetDll(htdDll hDll)
{
	mDll = hDll;
}
#else
void htdInit()
{
}
#endif

/*
	此文件是用来存放全局变量、全局函数（通用函数）
*/
#pragma once
#include "GameWinSock.h"
#include "GameProc.h"
 
extern 	GameWinSock* WinSock;
extern GameProc* PGameProc;
extern void InitClassProc(LPVOID proc_addr, unsigned value);

/*
	此文件是用来存放全局变量、全局函数（通用函数）
*/
#include "pch.h"
#include "extern_all.h"
GameWinSock* WinSock = nullptr;
GameProc* PGameProc = nullptr;
 
void InitClassProc(LPVOID proc_addr, unsigned value)
{
	unsigned* writer = (unsigned*)proc_addr;
	writer[0] = value;
}