本文实例讲述了C++基于hook iat改变Messagebox的方法，分享给大家供大家参考。具体方法如下：
步骤：
1. 定义原始函数类型的写法
//定义函数原型
typedef int (WINAPI *PFNMESSAGEBOX)(HWND hWnd, LPCTSTR lpText, LPCTSTR lpCaption, UINT uType);
//保存原始的MessageBox地址,注意这里
PROC g_orgProc = (PROC)MessageBox;
2. 先找到dll，找到后设置标志
if (stricmp(pszDllName, "user32.dll") == 0)//如果是user32.dll
{
bFindDll = TRUE;
break;
}
3. 找到dll后，查找函数名称
//在这里是比较的函数名称
if (stricmp(pszFuncName, "MessageBoxA") == 0)
{
//取得函数地址
PDWORD lpAddr = (DWORD*)((BYTE*)hModule + pImportDesc->FirstThunk) + n; //从第一个函数的地址，以后每次+4字节
//在这里是比较的函数地址
printf("addrss:%X\n", lpAddr);
DWORD* lpNewProc = (DWORD*)MyMessageBox;
::WriteProcessMemory(GetCurrentProcess(), lpAddr, &lpNewProc, sizeof(DWORD), NULL);
return;
}
当然 在3.中，也可以根据函数地址比较
#include <windows.h>
#include <stdio.h>
//定义函数原型
typedef int (WINAPI *PFNMESSAGEBOX)(HWND hWnd, LPCTSTR lpText, LPCTSTR lpCaption, UINT uType);
//保存原始的MessageBox地址,注意这里
PROC g_orgProc = (PROC)MessageBox;
int MyMessageBox(HWND hWnd, LPCTSTR lpText, LPCTSTR lpCaption, UINT uType)
{
return ((PFNMESSAGEBOX)g_orgProc)(hWnd, "mymessagebox", lpCaption, uType);
}
void SetHook()
{
HMODULE hModule = ::GetModuleHandleA(NULL);
IMAGE_DOS_HEADER* pDosHeader = (IMAGE_DOS_HEADER*)hModule;
IMAGE_OPTIONAL_HEADER* pOpNtHeader = (IMAGE_OPTIONAL_HEADER*)((BYTE*)hModule + pDosHeader->e_lfanew + 24); //这里加24
IMAGE_IMPORT_DESCRIPTOR* pImportDesc = (IMAGE_IMPORT_DESCRIPTOR*)((BYTE*)hModule + pOpNtHeader->DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress);
BOOL bFindDll = FALSE;
while (pImportDesc->FirstThunk)
{
char* pszDllName = (char*)((BYTE*)hModule + pImportDesc->Name);
printf("模块名称:%s\n", pszDllName);
if (stricmp(pszDllName, "user32.dll") == 0)//如果是user32.dll
{
bFindDll = TRUE;
break;
}
pImportDesc++;
}
if (bFindDll)
{
DWORD n = 0;
//一个IMAGE_THUNK_DATA就是一个导入函数
IMAGE_THUNK_DATA* pThunk = (IMAGE_THUNK_DATA*)((BYTE*)hModule + pImportDesc->OriginalFirstThunk);
while (pThunk->u1.Function)
{
//取得函数名称
char* pszFuncName = (char*)((BYTE*)hModule+pThunk->u1.AddressOfData+2); //函数名前面有两个..
printf("function name:%-25s, ", pszFuncName);
//在这里是比较的函数名称
if (stricmp(pszFuncName, "MessageBoxA") == 0)
{
//取得函数地址
PDWORD lpAddr = (DWORD*)((BYTE*)hModule + pImportDesc->FirstThunk) + n; //从第一个函数的地址，以后每次+4字节
//在这里是比较的函数地址
printf("addrss:%X\n", lpAddr);
DWORD* lpNewProc = (DWORD*)MyMessageBox;
::WriteProcessMemory(GetCurrentProcess(), lpAddr, &lpNewProc, sizeof(DWORD), NULL);
return;
}
n++; //每次增加一个DWORD
}
printf("\n");
}
}
int main(int argc, char* argv[])
{
::MessageBoxA(NULL, "before hook", "", MB_OK);
SetHook();
::MessageBoxA(NULL, "AFTERE hook", "", MB_OK);
return 0;
}
下面这个是比较函数地址的版本
#include <windows.h>
#include <stdio.h>
//定义函数原型
typedef int (WINAPI *PFNMESSAGEBOX)(HWND hWnd, LPCTSTR lpText, LPCTSTR lpCaption, UINT uType);
//保存原始的MessageBox地址,注意这里
PROC g_orgProc = (PROC)MessageBox;
int MyMessageBox(HWND hWnd, LPCTSTR lpText, LPCTSTR lpCaption, UINT uType)
{
return ((PFNMESSAGEBOX)g_orgProc)(hWnd, "mymessagebox", lpCaption, uType);
}
void SetHook()
{
HMODULE hModule = ::GetModuleHandleA(NULL);
IMAGE_DOS_HEADER* pDosHeader = (IMAGE_DOS_HEADER*)hModule;
IMAGE_OPTIONAL_HEADER* pOpNtHeader = (IMAGE_OPTIONAL_HEADER*)((BYTE*)hModule + pDosHeader->e_lfanew + 24); //这里加24
IMAGE_IMPORT_DESCRIPTOR* pImportDesc = (IMAGE_IMPORT_DESCRIPTOR*)((BYTE*)hModule + pOpNtHeader->DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress);
BOOL bFindDll = FALSE;
while (pImportDesc->FirstThunk)
{
char* pszDllName = (char*)((BYTE*)hModule + pImportDesc->Name);
printf("模块名称:%s\n", pszDllName);
if (stricmp(pszDllName, "user32.dll") == 0)//如果是user32.dll
{
bFindDll = TRUE;
break;
}
pImportDesc++;
}
if (bFindDll)
{
DWORD n = 0;
//一个IMAGE_THUNK_DATA就是一个导入函数
IMAGE_THUNK_DATA* pThunk = (IMAGE_THUNK_DATA*)((BYTE*)hModule + pImportDesc->OriginalFirstThunk);
while (pThunk->u1.Function)
{
//取得函数名称
char* pszFuncName = (char*)((BYTE*)hModule+pThunk->u1.AddressOfData+2); //函数名前面有两个..
printf("function name:%-25s, ", pszFuncName);
//取得函数地址
PDWORD lpAddr = (DWORD*)((BYTE*)hModule + pImportDesc->FirstThunk) + n; //从第一个函数的地址，以后每次+4字节
printf("addrss:%X\n", lpAddr);
//在这里是比较的函数地址
if (*lpAddr == (DWORD)g_orgProc)
{
DWORD* lpNewProc = (DWORD*)MyMessageBox;
::WriteProcessMemory(GetCurrentProcess(), lpAddr, &lpNewProc, sizeof(DWORD), NULL);
return;
}
n++; //每次增加一个DWORD
}
printf("\n");
}
}
int main(int argc, char* argv[])
{
::MessageBoxA(NULL, "before hook", "", MB_OK);
SetHook();
::MessageBoxA(NULL, "AFTERE hook", "", MB_OK);
return 0;
}
附上修改内存页保护属性的代码：
//修改内存页的保护属性
::VirtualQuery(lpAddr, &mbi, sizeof(MEMORY_BASIC_INFORMATION));
::VirtualProtect(lpAddr, sizeof(DWORD), PAGE_READWRITE, &dwOldProtect);
::WriteProcessMemory(GetCurrentProcess(), lpAddr, &lpNewProc, sizeof(DWORD), NULL);
::VirtualProtect(lpAddr, sizeof(DWORD), dwOldProtect, NULL);
希望本文所述对大家的C++程序设计有所帮助。