远程线程注入是最常用的一种注入技术，在应用层注入是通过CreateRemoteThread这个函数实现的，该函数通过创建线程并调用 LoadLibrary动态载入指定的DLL来实现注入，而在内核层同样存在一个类似的内核函数RtlCreateUserThread，但需要注意的是此函数未被公开，RtlCreateUserThread其实是对NtCreateThreadEx的包装，但最终会调用ZwCreateThread来实现注入，RtlCreateUserThread是CreateRemoteThread的底层实现。

基于LoadLibrary实现的注入原理可以具体分为如下几步；

(资料图)

总结起来就是首先在目标进程申请一块空间，空间里面写入要注入的DLL的路径字符串或者是一段ShellCode，找到该内存中LoadLibrary的基址并传入到RtlCreateUserThread中，此时进程自动加载我们指定路径下的DLL文件。

注入依赖于RtlCreateUserThread这个未到处内核函数，该内核函数中最需要关心的参数是ProcessHandle用于接收进程句柄，StartAddress接收一个函数地址，StartParameter用于对函数传递参数，具体的函数原型如下所示；

typedef DWORD(WINAPI* pRtlCreateUserThread)(    IN HANDLE                    ProcessHandle,          // 进程句柄    IN PSECURITY_DESCRIPTOR      SecurityDescriptor,    IN BOOL                      CreateSuspended,    IN ULONG                     StackZeroBits,    IN OUT PULONG                StackReserved,    IN OUT PULONG                StackCommit,    IN LPVOID                    StartAddress,          // 执行函数地址 LoadLibraryW    IN LPVOID                    StartParameter,        // 参数传递    OUT HANDLE                   ThreadHandle,          // 线程句柄    OUT LPVOID                   ClientID    );

由于我们加载DLL使用的是LoadLibraryW函数，此函数在运行时只需要一个参数，我们可以将DLL的路径传递进去，并调用LoadLibraryW以此来将特定模块拉起，该函数的定义规范如下所示；

HMODULE LoadLibraryW(  [in] LPCWSTR lpLibFileName);

根据上一篇文章中针对注入头文件lyshark.h的封装，本章将继续使用这个头文件中的函数，首先我们实现这样一个功能，将一段准备好的UCHAR字符串动态的写出到应用层进程内存，并以宽字节模式写出在对端内存中，这段代码可以写为如下样子；

// 署名权// right to sign one"s name on a piece of work// PowerBy: LyShark// Email: me@lyshark.com#include "lyshark.h"// 驱动卸载例程VOID UnDriver(PDRIVER_OBJECT driver){DbgPrint("Uninstall Driver \n");}// 驱动入口地址NTSTATUS DriverEntry(IN PDRIVER_OBJECT Driver, PUNICODE_STRING RegistryPath){DbgPrint("Hello LyShark \n");DWORD process_id = 7112;DWORD create_size = 1024;DWORD64 ref_address = 0;// 分配内存堆 《内核远程堆分配与销毁》 核心代码NTSTATUS Status = AllocMemory(process_id, create_size, &ref_address);DbgPrint("对端进程: %d \n", process_id);DbgPrint("分配长度: %d \n", create_size);DbgPrint("[*] 分配内核堆基址: %p \n", ref_address);UCHAR DllPath[256] = "C:\\hook.dll";UCHAR Item[256] = { 0 };// 将字节转为双字for (int x = 0, y = 0; x < strlen(DllPath) * 2; x += 2, y++){Item[x] = DllPath[y];}// 写出内存 《内核MDL读写进程内存》 核心代码ReadMemoryStruct ptr;ptr.pid = process_id;ptr.address = ref_address;ptr.size = strlen(DllPath) * 2;// 需要写入的数据ptr.data = ExAllocatePool(PagedPool, ptr.size);// 循环设置for (int i = 0; i < ptr.size; i++){ptr.data[i] = Item[i];}// 写内存MDLWriteMemory(&ptr);Driver->DriverUnload = UnDriver;return STATUS_SUCCESS;}

运行如上方所示的代码，将会在目标进程7112中开辟一段内存空间，并写出C:\hook.dll字符串，运行效果图如下所示；

此处你可以通过x64dbg附加到应用层进程内，并观察内存0000000002200000会看到如下字符串已被写出，双字类型则是每一个字符空一格，效果图如下所示；

继续实现所需要的子功能，实现动态获取Kernel32.dll模块里面LiadLibraryW这个导出函数的内存地址，这段代码相信你可以很容易的写出来，根据上节课的知识点我们可以二次封装一个GetProcessAddress来实现对特定模块基址的获取功能，如下是完整代码案例；

// 署名权// right to sign one"s name on a piece of work// PowerBy: LyShark// Email: me@lyshark.com#include "lyshark.h"// 实现取模块基址PVOID GetProcessAddress(HANDLE ProcessID, PWCHAR DllName, PCCHAR FunctionName){PEPROCESS EProcess = NULL;NTSTATUS Status = STATUS_SUCCESS;KAPC_STATE ApcState;PVOID RefAddress = 0;// 根据PID得到进程EProcess结构Status = PsLookupProcessByProcessId(ProcessID, &EProcess);if (Status != STATUS_SUCCESS){return Status;}// 判断目标进程是32位还是64位BOOLEAN IsWow64 = (PsGetProcessWow64Process(EProcess) != NULL) ? TRUE : FALSE;// 验证地址是否可读if (!MmIsAddressValid(EProcess)){return NULL;}// 将当前线程连接到目标进程的地址空间(附加进程)KeStackAttachProcess((PRKPROCESS)EProcess, &ApcState);__try{UNICODE_STRING DllUnicodeString = { 0 };PVOID BaseAddress = NULL;// 得到进程内模块基地址RtlInitUnicodeString(&DllUnicodeString, DllName);BaseAddress = GetUserModuleAddress(EProcess, &DllUnicodeString, IsWow64);if (!BaseAddress){return NULL;}DbgPrint("[*] 模块基址: %p \n", BaseAddress);// 得到该函数地址RefAddress = GetModuleExportAddress(BaseAddress, FunctionName, EProcess);DbgPrint("[*] 函数地址: %p \n", RefAddress);}__except (EXCEPTION_EXECUTE_HANDLER){return NULL;}// 取消附加KeUnstackDetachProcess(&ApcState);return RefAddress;}VOID Unload(PDRIVER_OBJECT pDriverObj){DbgPrint("[-] 驱动卸载 \n");}NTSTATUS DriverEntry(PDRIVER_OBJECT DriverObject, PUNICODE_STRING RegPath){DbgPrint("Hello LyShark.com \n");// 取模块基址PVOID pLoadLibraryW = GetProcessAddress(5200, L"kernel32.dll", "LoadLibraryW");DbgPrint("[*] 所在内存地址 = %p \n", pLoadLibraryW);DriverObject->DriverUnload = Unload;return STATUS_SUCCESS;}

编译并运行如上驱动代码，将自动获取PID=5200进程中Kernel32.dll模块内的LoadLibraryW的内存地址，输出效果图如下所示；

实现注入的最后一步就是调用自定义函数MyCreateRemoteThread该函数实现原理是调用RtlCreateUserThread开线程执行，这段代码的最终实现如下所示；

// 署名权// right to sign one"s name on a piece of work// PowerBy: LyShark// Email: me@lyshark.com#include "lyshark.h"// 定义函数指针typedef PVOID(NTAPI* PfnRtlCreateUserThread)(IN HANDLE ProcessHandle,IN PSECURITY_DESCRIPTOR SecurityDescriptor,IN BOOLEAN CreateSuspended,IN ULONG StackZeroBits,IN OUT size_t StackReserved,IN OUT size_t StackCommit,IN PVOID StartAddress,IN PVOID StartParameter,OUT PHANDLE ThreadHandle,OUT PCLIENT_ID ClientID);// 实现取模块基址PVOID GetProcessAddress(HANDLE ProcessID, PWCHAR DllName, PCCHAR FunctionName){PEPROCESS EProcess = NULL;NTSTATUS Status = STATUS_SUCCESS;KAPC_STATE ApcState;PVOID RefAddress = 0;// 根据PID得到进程EProcess结构Status = PsLookupProcessByProcessId(ProcessID, &EProcess);if (Status != STATUS_SUCCESS){return Status;}// 判断目标进程是32位还是64位BOOLEAN IsWow64 = (PsGetProcessWow64Process(EProcess) != NULL) ? TRUE : FALSE;// 验证地址是否可读if (!MmIsAddressValid(EProcess)){return NULL;}// 将当前线程连接到目标进程的地址空间(附加进程)KeStackAttachProcess((PRKPROCESS)EProcess, &ApcState);__try{UNICODE_STRING DllUnicodeString = { 0 };PVOID BaseAddress = NULL;// 得到进程内模块基地址RtlInitUnicodeString(&DllUnicodeString, DllName);BaseAddress = GetUserModuleAddress(EProcess, &DllUnicodeString, IsWow64);if (!BaseAddress){return NULL;}DbgPrint("[*] 模块基址: %p \n", BaseAddress);// 得到该函数地址RefAddress = GetModuleExportAddress(BaseAddress, FunctionName, EProcess);DbgPrint("[*] 函数地址: %p \n", RefAddress);}__except (EXCEPTION_EXECUTE_HANDLER){return NULL;}// 取消附加KeUnstackDetachProcess(&ApcState);return RefAddress;}// 远程线程注入函数BOOLEAN MyCreateRemoteThread(ULONG pid, PVOID pRing3Address, PVOID PParam){NTSTATUS status = STATUS_UNSUCCESSFUL;PEPROCESS pEProcess = NULL;KAPC_STATE ApcState = { 0 };PfnRtlCreateUserThread RtlCreateUserThread = NULL;HANDLE hThread = 0;__try{// 获取RtlCreateUserThread函数的内存地址UNICODE_STRING ustrRtlCreateUserThread;RtlInitUnicodeString(&ustrRtlCreateUserThread, L"RtlCreateUserThread");RtlCreateUserThread = (PfnRtlCreateUserThread)MmGetSystemRoutineAddress(&ustrRtlCreateUserThread);if (RtlCreateUserThread == NULL){return FALSE;}// 根据进程PID获取进程EProcess结构status = PsLookupProcessByProcessId((HANDLE)pid, &pEProcess);if (!NT_SUCCESS(status)){return FALSE;}// 附加到目标进程内KeStackAttachProcess(pEProcess, &ApcState);// 验证进程是否可读写if (!MmIsAddressValid(pRing3Address)){return FALSE;}// 启动注入线程status = RtlCreateUserThread(ZwCurrentProcess(),NULL,FALSE,0,0,0,pRing3Address,PParam,&hThread,NULL);if (!NT_SUCCESS(status)){return FALSE;}return TRUE;}__finally{// 释放对象if (pEProcess != NULL){ObDereferenceObject(pEProcess);pEProcess = NULL;}// 取消附加进程KeUnstackDetachProcess(&ApcState);}return FALSE;}VOID Unload(PDRIVER_OBJECT pDriverObj){DbgPrint("[-] 驱动卸载 \n");}NTSTATUS DriverEntry(PDRIVER_OBJECT DriverObject, PUNICODE_STRING RegPath){DbgPrint("Hello LyShark.com \n");ULONG process_id = 5200;DWORD create_size = 1024;DWORD64 ref_address = 0;// -------------------------------------------------------// 取模块基址// -------------------------------------------------------PVOID pLoadLibraryW = GetProcessAddress(process_id, L"kernel32.dll", "LoadLibraryW");DbgPrint("[*] 所在内存地址 = %p \n", pLoadLibraryW);// -------------------------------------------------------// 应用层开堆// -------------------------------------------------------NTSTATUS Status = AllocMemory(process_id, create_size, &ref_address);DbgPrint("对端进程: %d \n", process_id);DbgPrint("分配长度: %d \n", create_size);DbgPrint("分配的内核堆基址: %p \n", ref_address);// 设置注入路径,转换为多字节UCHAR DllPath[256] = "C:\\lyshark_hook.dll";UCHAR Item[256] = { 0 };for (int x = 0, y = 0; x < strlen(DllPath) * 2; x += 2, y++){Item[x] = DllPath[y];}// -------------------------------------------------------// 写出数据到内存// -------------------------------------------------------ReadMemoryStruct ptr;ptr.pid = process_id;ptr.address = ref_address;ptr.size = strlen(DllPath) * 2;// 需要写入的数据ptr.data = ExAllocatePool(PagedPool, ptr.size);// 循环设置for (int i = 0; i < ptr.size; i++){ptr.data[i] = Item[i];}// 写内存MDLWriteMemory(&ptr);// -------------------------------------------------------// 执行开线程函数// -------------------------------------------------------// 执行线程注入// 参数1：PID// 参数2：LoadLibraryW内存地址// 参数3：当前DLL路径BOOLEAN flag = MyCreateRemoteThread(process_id, pLoadLibraryW, ref_address);if (flag == TRUE){DbgPrint("[*] 已完成进程 %d 注入文件 %s \n", process_id, DllPath);}DriverObject->DriverUnload = Unload;return STATUS_SUCCESS;}

编译这段驱动程序，并将其放入虚拟机中，在C盘下面放置好一个名为lyshark_hook.dll文件，运行驱动程序将自动插入DLL到Win32Project进程内，输出效果图如下所示；

回到应用层进程，则可看到如下图所示的注入成功提示信息；