使用API-HOOK修改IAT的地址

来源：互联网发布：sql语句单引号转义编辑：程序博客网时间：2024/04/30 05:29

#include <windows.h>
#include <imagehlp.h>

#pragma comment(lib, "imagehlp.lib")

char *szModName = NULL;
char *szHacked = "my MessageBoxA！";
DWORD dwHookFun;
DWORD dwHookApiAddr;
PIMAGE_IMPORT_DESCRIPTOR pImportDesc;
PIMAGE_THUNK_DATA32 pThunk;
ULONG uSize;

void MyHook()
{
__asm
{
mov esp, ebp
push szHacked
pop DWORD PTR[esp + 12];//将szHacked的值赋给[esp+12]
pop ebp
jmp dwHookApiAddr
}
}

int main()
{
HMODULE hInstance = GetModuleHandle(NULL);
dwHookFun = (DWORD)MyHook;
dwHookApiAddr = (DWORD)GetProcAddress(LoadLibrary(TEXT("USER32.dll")), "MessageBoxA");

//通过函数ImageDirectroyEntryToData()获取IAT
pImportDesc = (PIMAGE_IMPORT_DESCRIPTOR)ImageDirectoryEntryToData(hInstance, TRUE, IMAGE_DIRECTORY_ENTRY_IMPORT, &uSize);

//找到要HOOK的函数所在的dll
while (pImportDesc->Name)
{
szModName = (char *)((PBYTE)hInstance + pImportDesc->Name);
if (strcmp(szModName, "USER32.dll") == 0)
{
break;
}
pImportDesc++;
}

//获取指向THUNK数组的指针
pThunk = (PIMAGE_THUNK_DATA32)((PBYTE)hInstance + pImportDesc->FirstThunk);

for (; pThunk->u1.Function; pThunk++)
{
if (pThunk->u1.Function == dwHookApiAddr)

{

//VirtualProtect()函数的第四个参数必须填写，否则返回false。

DWORD dwOldProtect;
if (VirtualProtect(&pThunk->u1.Function, 4096, PAGE_READWRITE, &dwOldProtect))
{
pThunk->u1.Function = (PDWORD)dwHookFun;
break;
}
}
}

MessageBoxA(0, "original MessageBoxA", "test", 0);
return 0;

}

结果如下：

0 0