反射式DLL注入实现（ManualMap，手动解析PE并映射到目标进程再运行）

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一般而言要注入DLL到一个目标进程最简单的方法 就是先获取DLL文件路径，然后在目标进程分配内存空间将路径写入到目标进程，写入到目标进程后再调用CreateRemoteThread()/NtCreateThread()/RtlCreateUserThread()函数来运行LoadLibraryA/W函数调用自己的DLL，这种方法的缺陷也很明显那就是容易被游戏检测到，很容易被游戏拦截，比如CSGO最新版就已经有这个限制了。 想要突破CSGO的限制注入DLL进去，我们可以采用反射式注入的方法（也可以先恢复CSGOhook的api进行远程线程注入），那么什么是反射式注入呢？又有什么有点呢？ 反射式dll注入与常规dll注入类似，而不同的地方在于反射式dll注入技术自己实现了一个reflective loader()函数来代替LoadLibaryA()函数去加载dll，示意图如下图所示。蓝色的线表示与用常规dll注入相同的步骤，红框中的是reflective loader()函数行为，也是下面重点描述的地方。

Reflective loader实现思路如下：

1.获得被注入进程未解析的dll的基地址。

2.获得必要的dll句柄和函数为修复导入表做准备。

3.分配一块新内存去取解析dll，并把pe头复制到新内存中和将各节复制到新内存中。

4.修复导入表和重定向表。 5.执行DllMain()函数。

核心代码如下：

ManualMapInject.h

#pragma once
#include "Injector.h"

using f_LoadLibraryA = HINSTANCE(WINAPI*)(const char* lpLibFilename);
using f_GetProcAddress = FARPROC(WINAPI*)(HMODULE hModule, LPCSTR lpProcName);
using f_DLL_ENTRY_POINT = BOOL(WINAPI*)(void* hDll, DWORD dwReason, void* pReserved);

#ifdef _WIN64
using f_RtlAddFunctionTable = BOOL(WINAPIV*)(PRUNTIME_FUNCTION FunctionTable, DWORD EntryCount, DWORD64 BaseAddress);
#endif

struct MANUAL_MAPPING_DATA
{
    f_LoadLibraryA pLoadLibraryA;
    f_GetProcAddress pGetProcAddress;
#ifdef _WIN64
    f_RtlAddFunctionTable pRtlAddFunctionTable;
#endif
    BYTE* pbase;
    HINSTANCE hMod;
    DWORD fdwReasonParam;
    LPVOID reservedParam;
    BOOL SEHSupport;
};


//Note: Exception support only x64 with build params /EHa or /EHc
bool ManualMapDll(HANDLE hProc, BYTE* pSrcData, SIZE_T FileSize, bool ClearHeader = true, bool ClearNonNeededSections = true, bool AdjustProtections = true, bool SEHExceptionSupport = true, DWORD fdwReason = DLL_PROCESS_ATTACH, LPVOID lpReserved = 0);
void __stdcall Shellcode(MANUAL_MAPPING_DATA* pData);

class CManualMapInject :public CInjector
{
public:
    CManualMapInject();
    virtual ~CManualMapInject();
    virtual bool InjectorDLL(TCHAR* szPath,DWORD dwPid);
};

ManualMapInject.cpp

#include "pch.h"
#include "ManualMapInject.h"


#ifdef _WIN64
#define CURRENT_ARCH IMAGE_FILE_MACHINE_AMD64
#else
#define CURRENT_ARCH IMAGE_FILE_MACHINE_I386
#endif
#define RELOC_FLAG32(RelInfo) ((RelInfo >>0x0C) == IMAGE_REL_BASED_HIGHLOW)
#define RELOC_FLAG64(RelInfo) ((RelInfo >>0x0C) == IMAGE_REL_BASED_DIR64)

#ifdef _WIN64
#define RELOC_FLAG RELOC_FLAG64
#else
#define RELOC_FLAG RELOC_FLAG32
#endif



CManualMapInject::CManualMapInject()
{
}

CManualMapInject::~CManualMapInject()
{
}

bool CManualMapInject::InjectorDLL(TCHAR* szPath, DWORD dwPid)
{
    HANDLE hProc = GetProcessHandle(dwPid);
    if (!hProc || !IsCorrectTargetArchitecture(hProc) || GetFileAttributes(szPath) == INVALID_FILE_ATTRIBUTES)
    {
        return false;
    }

//     std::ifstream File(szPath, std::ios::binary | std::ios::ate);
// 
//     if (File.fail())
//     {
//         printf("Opening the file failed: %X\n", (DWORD)File.rdstate());
//         File.close();
//         CloseHandle(hProc);
//         system("PAUSE");
//         return -5;
//     }
// 
//     auto FileSize = File.tellg();
//     if (FileSize <0x1000)
//     {
//         printf("Filesize invalid.\n");
//         File.close();
//         CloseHandle(hProc);
//         system("PAUSE");
//         return -6;
//     }
// 
//     BYTE* pSrcData = new BYTE[(UINT_PTR)FileSize];
//     if (!pSrcData)
//     {
//         printf("Can't allocate dll file.\n");
//         File.close();
//         CloseHandle(hProc);
//         system("PAUSE");
//         return -7;
//     }
// 
//     File.seekg(0, std::ios::beg);
//     File.read((char*)(pSrcData), FileSize);
//     File.close();
    CFile file;
    file.Open(szPath, CFile::modeRead);
    ULONGLONG nFileSize = file.GetLength();
    BYTE* pSrcData = new BYTE[nFileSize];
    ZeroMemory(pSrcData,nFileSize);
    file.SeekToBegin();
    file.Read(pSrcData,nFileSize);
    file.Close();

    if (!ManualMapDll(hProc, pSrcData, nFileSize))
    {
        delete[] pSrcData;
        CloseHandle(hProc);
        return false;
    }
    delete[] pSrcData;

    CloseHandle(hProc);
    return false;
}

bool ManualMapDll(HANDLE hProc, BYTE* pSrcData, SIZE_T FileSize, bool ClearHeader,
    bool ClearNonNeededSections, bool AdjustProtections, 
    bool SEHExceptionSupport, DWORD fdwReason, LPVOID lpReserved) 
{
    IMAGE_NT_HEADERS* pOldNtHeader = nullptr;
    IMAGE_OPTIONAL_HEADER* pOldOptHeader = nullptr;
    IMAGE_FILE_HEADER* pOldFileHeader = nullptr;
    BYTE* pTargetBase = nullptr;

    if (reinterpret_cast<IMAGE_DOS_HEADER*>(pSrcData)->e_magic != 0x5A4D)//"MZ"
    { 
        return false;
    }

    pOldNtHeader = reinterpret_cast<IMAGE_NT_HEADERS*>(pSrcData + reinterpret_cast<IMAGE_DOS_HEADER*>(pSrcData)->e_lfanew);
    pOldOptHeader = &pOldNtHeader->OptionalHeader;
    pOldFileHeader = &pOldNtHeader->FileHeader;

    if (pOldFileHeader->Machine != CURRENT_ARCH)
    {
        return false;
    }

    pTargetBase = reinterpret_cast<BYTE*>(VirtualAllocEx(hProc, nullptr, pOldOptHeader->SizeOfImage, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE));
    if (!pTargetBase)
    {
        return false;
    }

    DWORD oldp = 0;
    VirtualProtectEx(hProc, pTargetBase, pOldOptHeader->SizeOfImage, PAGE_EXECUTE_READWRITE, &oldp);

    MANUAL_MAPPING_DATA data{ 0 };
    data.pLoadLibraryA = LoadLibraryA;
    data.pGetProcAddress = GetProcAddress;
#ifdef _WIN64
    data.pRtlAddFunctionTable = (f_RtlAddFunctionTable)RtlAddFunctionTable;
#else 
    SEHExceptionSupport = false;
#endif
    data.pbase = pTargetBase;
    data.fdwReasonParam = fdwReason;
    data.reservedParam = lpReserved;
    data.SEHSupport = SEHExceptionSupport;


    //PE header
    if (!WriteProcessMemory(hProc, pTargetBase, pSrcData, 0x1000, nullptr)) //only first 0x1000 bytes for the header
    {
        VirtualFreeEx(hProc, pTargetBase, 0, MEM_RELEASE);
        return false;
    }

    IMAGE_SECTION_HEADER* pSectionHeader = IMAGE_FIRST_SECTION(pOldNtHeader);
    for (UINT i = 0; i != pOldFileHeader->NumberOfSections; ++i, ++pSectionHeader)
    {
        if (pSectionHeader->SizeOfRawData)
        {
            if (!WriteProcessMemory(hProc, pTargetBase + pSectionHeader->VirtualAddress, pSrcData + pSectionHeader->PointerToRawData, pSectionHeader->SizeOfRawData, nullptr)) 
            {
                VirtualFreeEx(hProc, pTargetBase, 0, MEM_RELEASE);
                return false;
            }
        }
    }

    //Mapping params
    BYTE* MappingDataAlloc = reinterpret_cast<BYTE*>(VirtualAllocEx(hProc, nullptr, sizeof(MANUAL_MAPPING_DATA), MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE));
    if (!MappingDataAlloc) 
    {
        VirtualFreeEx(hProc, pTargetBase, 0, MEM_RELEASE);
        return false;
    }

    if (!WriteProcessMemory(hProc, MappingDataAlloc, &data, sizeof(MANUAL_MAPPING_DATA), nullptr))
    {
        VirtualFreeEx(hProc, pTargetBase, 0, MEM_RELEASE);
        VirtualFreeEx(hProc, MappingDataAlloc, 0, MEM_RELEASE);
        return false;
    }

    //Shell code
    void* pShellcode = VirtualAllocEx(hProc, nullptr, 0x1000, MEM_COMMIT | MEM_RESERVE, PAGE_EXECUTE_READWRITE);
    if (!pShellcode)
    {
        VirtualFreeEx(hProc, pTargetBase, 0, MEM_RELEASE);
        VirtualFreeEx(hProc, MappingDataAlloc, 0, MEM_RELEASE);
        return false;
    }

    if (!WriteProcessMemory(hProc, pShellcode, Shellcode, 0x1000, nullptr))
    {
        VirtualFreeEx(hProc, pTargetBase, 0, MEM_RELEASE);
        VirtualFreeEx(hProc, MappingDataAlloc, 0, MEM_RELEASE);
        VirtualFreeEx(hProc, pShellcode, 0, MEM_RELEASE);
        return false;
    }


    HANDLE hThread = CreateRemoteThread(hProc, nullptr, 0, reinterpret_cast<LPTHREAD_START_ROUTINE>(pShellcode), MappingDataAlloc, 0, nullptr);
    if (!hThread) 
    {
        VirtualFreeEx(hProc, pTargetBase, 0, MEM_RELEASE);
        VirtualFreeEx(hProc, MappingDataAlloc, 0, MEM_RELEASE);
        VirtualFreeEx(hProc, pShellcode, 0, MEM_RELEASE);
        return false;
    }
    WaitForSingleObject(hThread, INFINITE);
    CloseHandle(hThread);


    HINSTANCE hCheck = NULL;
    while (!hCheck) 
    {
        DWORD exitcode = 0;
        GetExitCodeProcess(hProc, &exitcode);
        if (exitcode != STILL_ACTIVE)
        {
            return false;
        }

        MANUAL_MAPPING_DATA data_checked{ 0 };
        ReadProcessMemory(hProc, MappingDataAlloc, &data_checked, sizeof(data_checked), nullptr);
        hCheck = data_checked.hMod;

        if (hCheck == (HINSTANCE)0x404040) 
        {
            VirtualFreeEx(hProc, pTargetBase, 0, MEM_RELEASE);
            VirtualFreeEx(hProc, MappingDataAlloc, 0, MEM_RELEASE);
            VirtualFreeEx(hProc, pShellcode, 0, MEM_RELEASE);
            return false;
        }
        else if (hCheck == (HINSTANCE)0x505050)
        {
            //Exception support failed!
        }

        Sleep(10);
    }

    BYTE* emptyBuffer = (BYTE*)malloc(1024 * 1024 * 20);
    if (emptyBuffer == nullptr)
    {
        return false;
    }
    memset(emptyBuffer, 0, 1024 * 1024 * 20);

    //CLEAR PE HEAD
    if (ClearHeader)
    {
        WriteProcessMemory(hProc, pTargetBase, emptyBuffer, 0x1000, nullptr);
    }
    //END CLEAR PE HEAD


    if (ClearNonNeededSections)
    {
        pSectionHeader = IMAGE_FIRST_SECTION(pOldNtHeader);
        for (UINT i = 0; i != pOldFileHeader->NumberOfSections; ++i, ++pSectionHeader) 
        {
            if (pSectionHeader->Misc.VirtualSize)
            {
                if ((SEHExceptionSupport ? 0 : strcmp((char*)pSectionHeader->Name, ".pdata") == 0) ||
                    strcmp((char*)pSectionHeader->Name, ".rsrc") == 0 ||
                    strcmp((char*)pSectionHeader->Name, ".reloc") == 0) 
                {
                    WriteProcessMemory(hProc, pTargetBase + pSectionHeader->VirtualAddress, emptyBuffer, pSectionHeader->Misc.VirtualSize, nullptr);
                }
            }
        }
    }

    if (AdjustProtections)
    {
        pSectionHeader = IMAGE_FIRST_SECTION(pOldNtHeader);
        for (UINT i = 0; i != pOldFileHeader->NumberOfSections; ++i, ++pSectionHeader)
        {
            if (pSectionHeader->Misc.VirtualSize)
            {
                DWORD old = 0;
                DWORD newP = PAGE_READONLY;

                if ((pSectionHeader->Characteristics & IMAGE_SCN_MEM_WRITE) >0) 
                {
                    newP = PAGE_READWRITE;
                }
                else if ((pSectionHeader->Characteristics & IMAGE_SCN_MEM_EXECUTE) >0) 
                {
                    newP = PAGE_EXECUTE_READ;
                }
                VirtualProtectEx(hProc, pTargetBase + pSectionHeader->VirtualAddress, pSectionHeader->Misc.VirtualSize, newP, &old);
            }
        }
        DWORD old = 0;
        VirtualProtectEx(hProc, pTargetBase, IMAGE_FIRST_SECTION(pOldNtHeader)->VirtualAddress, PAGE_READONLY, &old);
    }

    WriteProcessMemory(hProc, pShellcode, emptyBuffer, 0x1000, nullptr);
    VirtualFreeEx(hProc, pShellcode, 0, MEM_RELEASE);
    VirtualFreeEx(hProc, MappingDataAlloc, 0, MEM_RELEASE);

    return true;
}



//#pragma runtime_checks( "", off )
//#pragma optimize( "", off )
void __stdcall Shellcode(MANUAL_MAPPING_DATA* pData)
{
    if (!pData)
    {
        pData->hMod = (HINSTANCE)0x404040;
        return;
    }

    BYTE* pBase = pData->pbase;
    auto* pOpt = &reinterpret_cast<IMAGE_NT_HEADERS*>(pBase + reinterpret_cast<IMAGE_DOS_HEADER*>((uintptr_t)pBase)->e_lfanew)->OptionalHeader;

    auto _LoadLibraryA = pData->pLoadLibraryA;
    auto _GetProcAddress = pData->pGetProcAddress;
#ifdef _WIN64
    auto _RtlAddFunctionTable = pData->pRtlAddFunctionTable;
#endif
    auto _DllMain = reinterpret_cast<f_DLL_ENTRY_POINT>(pBase + pOpt->AddressOfEntryPoint);

    BYTE* LocationDelta = pBase - pOpt->ImageBase;
    if (LocationDelta) {
        if (pOpt->DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].Size)
        {
            auto* pRelocData = reinterpret_cast<IMAGE_BASE_RELOCATION*>(pBase + pOpt->DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].VirtualAddress);
            const auto* pRelocEnd = reinterpret_cast<IMAGE_BASE_RELOCATION*>(reinterpret_cast<uintptr_t>(pRelocData) + pOpt->DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].Size);
            while (pRelocData