USER
create a user mode aplication for this
#include <ntifs.h>
#include <ntddk.h>
// ==========================================================
// Definitions and Macros
// ==========================================================
#define TARGET_PROCESS_NAME L"notepad.exe" // Replace with your target process name
#define MY_WNF_STATE_NAME 0x41C64E6DA3BC1074ULL // Replace with your unique value
// Windows Build Numbers
#define WINDOWS_1803 17134
#define WINDOWS_1809 17763
#define WINDOWS_1903 18362
#define WINDOWS_1909 18363
#define WINDOWS_2004 19041
#define WINDOWS_20H2 19569
#define WINDOWS_21H1 20180
// Page size definitions
#define PAGE_OFFSET_SIZE 12
#define PMASK (0xfull << 8) & 0xFFFFFFFFfull
// ==========================================================
// Function Pointer Types for WNF (Undocumented APIs)
// ==========================================================
typedef NTSTATUS (PExSubscribeWnfStateChange)(
PWNF_STATE_NAME StateName,
WNF_CHANGE_STAMP ChangeStamp,
WNF_SUBSCRIPTION_FLAG SubscriptionFlag,
PVOID Callback,
PVOID CallbackContext,
PCWNF_TYPE_ID TypeId,
PVOID DeliveryDescriptor,
ULONG DeliveryDescriptorSize
);
typedef NTSTATUS (PExPublishWnfStateData)(
PCWNF_STATE_NAME StateName,
PVOID Buffer,
ULONG Length,
PCWNF_TYPE_ID TypeId,
PVOID ExplicitScope,
ULONG MatchingChangeStamp
);
// Global function pointers
PExPublishWnfStateData ExPublishWnfStateDataFunc = NULL;
// ==========================================================
// Data Structures
// ==========================================================
typedef struct _INSTRUCTIONS {
BOOLEAN close;
BOOLEAN read;
BOOLEAN reqBase;
PVOID bufferAddress;
UINT_PTR address;
ULONGLONG size;
PVOID output;
ULONG64 baseAddress;
const char moduleName;
} INSTRUCTIONS, PINSTRUCTIONS;
// ==========================================================
// Function Declarations
// ==========================================================
NTKERNELAPI
PVOID
PsGetProcessSectionBaseAddress(
__in PEPROCESS Process
);
PVOID GetProcessBaseAddress(HANDLE pid);
DWORD GetUserDirectoryTableBaseOffset();
ULONG_PTR GetProcessCr3(PEPROCESS pProcess);
ULONG_PTR GetKernelDirBase();
NTSTATUS ReadVirtual(uint64_t dirbase, uint64_t address, uint8_t buffer, SIZE_T size, SIZE_T read);
NTSTATUS WriteVirtual(uint64_t dirbase, uint64_t address, uint8_t* buffer, SIZE_T size, SIZE_T* written);
NTSTATUS ReadPhysicalAddress(PVOID TargetAddress, PVOID lpBuffer, SIZE_T Size, SIZE_T* BytesRead);
NTSTATUS WritePhysicalAddress(PVOID TargetAddress, PVOID lpBuffer, SIZE_T Size, SIZE_T* BytesWritten);
uint64_t TranslateLinearAddress(uint64_t directoryTableBase, uint64_t virtualAddress);
NTSTATUS ReadProcessMemory(int pid, PVOID Address, PVOID AllocatedBuffer, SIZE_T size, SIZE_T* read);
NTSTATUS WriteProcessMemory(int pid, PVOID Address, PVOID AllocatedBuffer, SIZE_T size, SIZE_T* written);
VOID ProcessNotifyCallback(
__in HANDLE ParentId,
__in HANDLE ProcessId,
__in BOOLEAN Create
);
VOID DriverUnload(PDRIVER_OBJECT DriverObject);
// ==========================================================
// Function Definitions
// ==========================================================
// Retrieve the base address of a process given its PID
PVOID GetProcessBaseAddress(HANDLE pid)
{
PEPROCESS pProcess = NULL;
if (pid == NULL) return NULL;
NTSTATUS NtRet = PsLookupProcessByProcessId(pid, &pProcess);
if (NtRet != STATUS_SUCCESS) return NULL;
PVOID Base = PsGetProcessSectionBaseAddress(pProcess);
ObDereferenceObject(pProcess);
return Base;
}
// Get the offset for the UserDirectoryTableBase based on Windows version
DWORD GetUserDirectoryTableBaseOffset()
{
RTL_OSVERSIONINFOW ver = { 0 };
RtlGetVersion(&ver);
switch (ver.dwBuildNumber)
{
case WINDOWS_1803:
case WINDOWS_1809:
return 0x0278;
case WINDOWS_1903:
case WINDOWS_1909:
case WINDOWS_2004:
case WINDOWS_20H2:
case WINDOWS_21H1:
default:
return 0x0388;
}
}
// Retrieve the CR3 (Page Directory Base) of a process
ULONG_PTR GetProcessCr3(PEPROCESS pProcess)
{
PUCHAR process = (PUCHAR)pProcess;
#ifdef _WIN64
ULONG_PTR process_dirbase = (PULONG_PTR)(process + 0x28); // dirbase for x64
#else
ULONG_PTR process_dirbase = (PULONG_PTR)(process + 0x18); // dirbase for x86
#endif
if (process_dirbase == 0)
{
DWORD UserDirOffset = GetUserDirectoryTableBaseOffset();
ULONG_PTR process_userdirbase = (PULONG_PTR)(process + UserDirOffset);
return process_userdirbase;
}
return process_dirbase;
}
// Example function to get the kernel's CR3 (for demonstration; typically not used)
ULONG_PTR GetKernelDirBase()
{
// Note: Accessing the kernel's CR3 is generally unsafe and not recommended
// This is just for illustrative purposes
return __readcr3();
}
// Translate a virtual address to a physical address using the provided directory table base
uint64_t TranslateLinearAddress(uint64_t directoryTableBase, uint64_t virtualAddress) {
directoryTableBase &= 0xf;
uint64_t pageOffset = virtualAddress & 0xFFF;
uint64_t pte = (virtualAddress >> 12) & 0x1FF;
uint64_t pt = (virtualAddress >> 21) & 0x1FF;
uint64_t pd = (virtualAddress >> 30) & 0x1FF;
uint64_t pdp = (virtualAddress >> 39) & 0x1FF;
SIZE_T readsize = 0;
uint64_t pdpe = 0;
if (!NT_SUCCESS(ReadPhysicalAddress((PVOID)(directoryTableBase + 8 * pdp), &pdpe, sizeof(pdpe), &readsize)) || (pdpe & 1))
return 0;
uint64_t pde = 0;
if (!NT_SUCCESS(ReadPhysicalAddress((PVOID)((pdpe & PMASK) + 8 * pd), &pde, sizeof(pde), &readsize)) || (pde & 1))
return 0;
// 1GB large page
if (pde & 0x80)
return (pde & 0x000FFFFFFFF000ULL) + (virtualAddress & 0x3FFFFFFFUL);
uint64_t pteAddr = 0;
if (!NT_SUCCESS(ReadPhysicalAddress((PVOID)((pde & PMASK) + 8 * pt), &pteAddr, sizeof(pteAddr), &readsize)) || (pteAddr & 1))
return 0;
// 2MB large page
if (pteAddr & 0x80)
return (pteAddr & PMASK) + (virtualAddress & 0x1FFFFFUL);
uint64_t physPage = 0;
if (!NT_SUCCESS(ReadPhysicalAddress((PVOID)(pteAddr & PMASK) + 8 * pte, &physPage, sizeof(physPage), &readsize)) || !(physPage & 1))
return 0;
physPage &= PMASK;
return physPage + pageOffset;
}
// Read a physical address into a buffer
NTSTATUS ReadPhysicalAddress(PVOID TargetAddress, PVOID lpBuffer, SIZE_T Size, SIZE_T BytesRead)
{
if (TargetAddress == NULL || lpBuffer == NULL || BytesRead == NULL)
return STATUS_INVALID_PARAMETER;
MM_COPY_ADDRESS AddrToRead = { 0 };
AddrToRead.PhysicalAddress.QuadPart = (ULONG_PTR)TargetAddress;
NTSTATUS status = MmCopyMemory(lpBuffer, AddrToRead, Size, MM_COPY_MEMORY_PHYSICAL, BytesRead);
return status;
}
// Write a buffer to a physical address
NTSTATUS WritePhysicalAddress(PVOID TargetAddress, PVOID lpBuffer, SIZE_T Size, SIZE_T BytesWritten)
{
if (!TargetAddress || !lpBuffer || !BytesWritten)
return STATUS_INVALID_PARAMETER;
PHYSICAL_ADDRESS AddrToWrite = { 0 };
AddrToWrite.QuadPart = (ULONG_PTR)TargetAddress;
// Limit MmMapIoSpaceEx to PAGE_SIZE (4096 bytes)
if (Size > PAGE_SIZE)
return STATUS_INVALID_PARAMETER;
PVOID pmapped_mem = MmMapIoSpaceEx(AddrToWrite, Size, PAGE_READWRITE);
if (!pmapped_mem)
return STATUS_UNSUCCESSFUL;
RtlCopyMemory(pmapped_mem, lpBuffer, Size);
BytesWritten = Size;
MmUnmapIoSpace(pmapped_mem, Size);
return STATUS_SUCCESS;
}
// Read virtual memory from a process
NTSTATUS ReadVirtual(uint64_t dirbase, uint64_t address, uint8_t buffer, SIZE_T size, SIZE_T read)
{
if (!buffer || !read)
return STATUS_INVALID_PARAMETER;
uint64_t paddress;
NTSTATUS status = STATUS_SUCCESS;
SIZE_T CurOffset = 0;
SIZE_T TotalSize = size;
while (TotalSize > 0)
{
paddress = TranslateLinearAddress(dirbase, address + CurOffset);
if (!paddress)
return STATUS_UNSUCCESSFUL;
ULONG64 ReadSize = min(PAGE_SIZE - (paddress & 0xFFF), TotalSize);
SIZE_T BytesRead = 0;
status = ReadPhysicalAddress((PVOID)paddress, buffer + CurOffset, ReadSize, &BytesRead);
if (!NT_SUCCESS(status) || BytesRead == 0)
break;
TotalSize -= BytesRead;
CurOffset += BytesRead;
}
read = CurOffset;
return status;
}
// Write virtual memory to a process
NTSTATUS WriteVirtual(uint64_t dirbase, uint64_t address, uint8_t buffer, SIZE_T size, SIZE_T* written)
{
if (!buffer || !written)
return STATUS_INVALID_PARAMETER;
uint64_t paddress;
NTSTATUS status = STATUS_SUCCESS;
SIZE_T CurOffset = 0;
SIZE_T TotalSize = size;
while (TotalSize > 0)
{
paddress = TranslateLinearAddress(dirbase, address + CurOffset);
if (!paddress)
return STATUS_UNSUCCESSFUL;
ULONG64 WriteSize = min(PAGE_SIZE - (paddress & 0xFFF), TotalSize);
SIZE_T BytesWrittenLocal = 0;
status = WritePhysicalAddress((PVOID)paddress, buffer + CurOffset, WriteSize, &BytesWrittenLocal);
if (!NT_SUCCESS(status) || BytesWrittenLocal == 0)
break;
TotalSize -= BytesWrittenLocal;
CurOffset += BytesWrittenLocal;
}
written = CurOffset;
return status;
}
// Read the memory of a process by PID
NTSTATUS ReadProcessMemory(int pid, PVOID Address, PVOID AllocatedBuffer, SIZE_T size, SIZE_T read)
{
if (pid == 0 || Address == NULL || AllocatedBuffer == NULL || read == NULL)
return STATUS_INVALID_PARAMETER;
PEPROCESS pProcess = NULL;
NTSTATUS NtRet = PsLookupProcessByProcessId((HANDLE)(ULONG_PTR)pid, &pProcess);
if (NtRet != STATUS_SUCCESS)
return NtRet;
ULONG_PTR process_dirbase = GetProcessCr3(pProcess);
ObDereferenceObject(pProcess);
NtRet = ReadVirtual(process_dirbase, (ULONG_PTR)Address, (uint8_t*)AllocatedBuffer, size, read);
return NtRet;
}
// Write the memory of a process by PID
NTSTATUS WriteProcessMemory(int pid, PVOID Address, PVOID AllocatedBuffer, SIZE_T size, SIZE_T* written)
{
if (pid == 0 || Address == NULL || AllocatedBuffer == NULL || written == NULL)
return STATUS_INVALID_PARAMETER;
PEPROCESS pProcess = NULL;
NTSTATUS NtRet = PsLookupProcessByProcessId((HANDLE)(ULONG_PTR)pid, &pProcess);
if (NtRet != STATUS_SUCCESS)
return NtRet;
ULONG_PTR process_dirbase = GetProcessCr3(pProcess);
ObDereferenceObject(pProcess);
NtRet = WriteVirtual(process_dirbase, (ULONG_PTR)Address, (uint8_t*)AllocatedBuffer, size, written);
return NtRet;
}
// Callback function for process creation/termination
VOID ProcessNotifyCallback(
__in HANDLE ParentId,
__in HANDLE ProcessId,
__in BOOLEAN Create
)
{
UNREFERENCED_PARAMETER(ParentId);
if (Create)
{
PEPROCESS pProcess = NULL;
NTSTATUS status = PsLookupProcessByProcessId(ProcessId, &pProcess);
if (NT_SUCCESS(status))
{
// Get process image file name
WCHAR imageName[300] = { 0 };
UNICODE_STRING uProcessImageName = { 0 };
// Use RtlQueryInformationProcess if SeLocateProcessImageName is unavailable
status = SeLocateProcessImageName(pProcess, &uProcessImageName);
if (NT_SUCCESS(status))
{
// Extract file name from full path
PWSTR processName = wcsrchr(uProcessImageName.Buffer, L'');
if (processName)
{
processName++; // Move past the backslash
// Check if this is the target process
if (_wcsicmp(processName, TARGET_PROCESS_NAME) == 0)
{
// Perform memory operations here
// Get base address
PVOID baseAddress = GetProcessBaseAddress(ProcessId);
if (baseAddress)
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_INFO_LEVEL, "[Driver] Base address of %ws: %p\n", processName, baseAddress);
// Example: Read some memory from the process
UCHAR buffer[256] = { 0 };
SIZE_T bytesRead = 0;
NTSTATUS ntStatus = ReadProcessMemory((int)(ULONG_PTR)ProcessId, baseAddress, buffer, sizeof(buffer), &bytesRead);
if (NT_SUCCESS(ntStatus))
{
// Do something with the read data
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_INFO_LEVEL, "[Driver] Successfully read %zu bytes from %ws\n", bytesRead, processName);
}
else
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_ERROR_LEVEL, "[Driver] Failed to read process memory: 0x%X\n", ntStatus);
}
// Example: Write to process memory (be cautious with actual addresses)
/
UCHAR writeData[256] = { / ... * / };
SIZE_T bytesWritten = 0;
ntStatus = WriteProcessMemory((int)(ULONG_PTR)ProcessId, baseAddress, writeData, sizeof(writeData), &bytesWritten);
if (NT_SUCCESS(ntStatus))
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_INFO_LEVEL, "[Driver] Successfully wrote %zu bytes to %ws\n", bytesWritten, processName);
}
else
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_ERROR_LEVEL, "[Driver] Failed to write process memory: 0x%X\n", ntStatus);
}
*/
}
else
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_ERROR_LEVEL, "[Driver] Failed to get base address of %ws\n", processName);
}
}
}
else
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_ERROR_LEVEL, "[Driver] Failed to parse process name\n");
}
// Free the UNICODE_STRING allocated by SeLocateProcessImageName
ExFreePoolWithTag(uProcessImageName.Buffer, 'imgN');
}
else
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_ERROR_LEVEL, "[Driver] SeLocateProcessImageName failed with status: 0x%X\n", status);
}
ObDereferenceObject(pProcess);
}
else
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_ERROR_LEVEL, "[Driver] PsLookupProcessByProcessId failed with status: 0x%X\n", status);
}
}
}
// Driver unload routine
VOID DriverUnload(PDRIVER_OBJECT DriverObject)
{
UNREFERENCED_PARAMETER(DriverObject);
// Remove the process notify routine
NTSTATUS status = PsSetCreateProcessNotifyRoutine(ProcessNotifyCallback, TRUE);
if (!NT_SUCCESS(status))
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_ERROR_LEVEL, "[Driver] Failed to remove process notify routine: 0x%X\n", status);
}
else
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_INFO_LEVEL, "[Driver] Process notify routine removed successfully\n");
}
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_INFO_LEVEL, "[Driver] Driver unloaded\n");
}
// ==========================================================
// WNF Functions and DriverEntry Implementation
// ==========================================================
// Function to initialize WNF communication
NTSTATUS InitializeWNF()
{
// Dynamically resolve the ExPublishWnfStateData function
UNICODE_STRING functionName;
RtlInitUnicodeString(&functionName, L"ExPublishWnfStateData");
ExPublishWnfStateDataFunc = (PExPublishWnfStateData)MmGetSystemRoutineAddress(&functionName);
if (ExPublishWnfStateDataFunc == NULL)
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_ERROR_LEVEL, "[Driver] Failed to resolve ExPublishWnfStateData\n");
return STATUS_UNSUCCESSFUL;
}
// Prepare your data
INSTRUCTIONS instructions = { 0 };
instructions.reqBase = TRUE;
instructions.baseAddress = 0x12345678; // Example base address
instructions.output = (PVOID)instructions.baseAddress;
// Publish the data to the WNF state
NTSTATUS status = ExPublishWnfStateDataFunc(
(PCWNF_STATE_NAME)&MY_WNF_STATE_NAME,
&instructions,
sizeof(INSTRUCTIONS),
NULL,
NULL,
0
);
if (!NT_SUCCESS(status))
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_ERROR_LEVEL, "[Driver] ExPublishWnfStateData failed: 0x%08X\n", status);
return status;
}
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_INFO_LEVEL, "[Driver] Published WNF state data successfully\n");
return STATUS_SUCCESS;
}
// Main DriverEntry function
NTSTATUS DriverEntry(PDRIVER_OBJECT DriverObject, PUNICODE_STRING RegistryPath)
{
UNREFERENCED_PARAMETER(RegistryPath);
NTSTATUS status;
// Register the process creation notify routine
status = PsSetCreateProcessNotifyRoutine(ProcessNotifyCallback, FALSE);
if (!NT_SUCCESS(status))
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_ERROR_LEVEL, "[Driver] PsSetCreateProcessNotifyRoutine failed: 0x%X\n", status);
return status;
}
else
{
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_INFO_LEVEL, "[Driver] Process notify routine set successfully\n");
}
// Initialize WNF communication
status = InitializeWNF();
if (!NT_SUCCESS(status))
{
// If WNF initialization fails, unload the driver
PsSetCreateProcessNotifyRoutine(ProcessNotifyCallback, TRUE);
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_ERROR_LEVEL, "[Driver] WNF initialization failed. Driver will unload.\n");
return status;
}
// Set the unload routine
DriverObject->DriverUnload = DriverUnload;
DbgPrintEx(DPFLTR_IHVDRIVER_ID, DPFLTR_INFO_LEVEL, "[Driver] Driver loaded successfully\n");
return STATUS_SUCCESS;
}
ASSISTANT
Creating a user-mode application to interact with the provided kernel-mode driver involves understanding how the driver communicates and what functionalities it exposes. The driver utilizes **Windows Notification Facility (WNF)** to publish state data, specifically through the `MY_WNF_STATE_NAME`. To create a user-mode application that interacts with this driver, you'll need to subscribe to the same WNF state to receive notifications and potentially send data back if required.
**Important Considerations:**
1. **Undocumented APIs:** WNF is not fully documented for user-mode applications. Interacting with WNF typically requires using internal and undocumented APIs. This means that such implementations can be unstable and may break with Windows updates.
2. **Permissions:** Subscribing to certain WNF states or interacting with kernel-mode drivers usually requires elevated privileges (Administrator rights).
3. **Libraries:** To simplify interacting with WNF, you can use libraries like [NtApiDotNet](https://github.com/TheWover/NtApiDotNet) which provide managed wrappers around many of the undocumented APIs.
4. **Safety and Stability:** Be cautious when interacting with kernel-mode components. Improper usage can lead to system instability or crashes.
Below is a **C++** example of a user-mode application that subscribes to the specified WNF state and handles the received `INSTRUCTIONS` structure. This example uses dynamic function loading since the WNF APIs are not officially documented for user-mode applications.
---
### **User-Mode Application in C++ to Subscribe to WNF State**
```cpp
#include <windows.h>
#include <winternl.h>
#include <iostream>
#include <thread>
#include <vector>
// Define the WNF_STATE_NAME as provided in the driver
#define MY_WNF_STATE_NAME 0x41C64E6DA3BC1074ULL
// Define the INSTRUCTIONS structure matching the driver's definition
#pragma pack(push, 1)
typedef struct _INSTRUCTIONS {
BOOLEAN close;
BOOLEAN read;
BOOLEAN reqBase;
PVOID bufferAddress;
UINT_PTR address;
ULONGLONG size;
PVOID output;
ULONG64 baseAddress;
CHAR moduleName[256]; // Assuming moduleName is a string with max 256 chars
} INSTRUCTIONS, *PINSTRUCTIONS;
#pragma pack(pop)
// Function pointer types for WNF APIs
typedef NTSTATUS(NTAPI* NtSubscribeWnfStateChange_t)(
WNF_STATE_NAME StateName,
PVOID CallbackContext,
ULONG CallbackLength,
PVOID Callback,
ULONG DesiredAccess,
ULONG Flags
);
typedef NTSTATUS(NTAPI* NtWaitForWnfStateChange_t)(
WNF_CHANGE_STAMP* ChangeStamp,
WNF_STATE_NAME StateName,
PVOID MatchAnyValue,
ULONG MatchAnyLength,
PVOID MatchAllValue,
ULONG MatchAllLength,
PLARGE_INTEGER Timeout,
PVOID Buffer,
ULONG BufferSize,
PULONG ReturnedLength
);
// Load NtSubscribeWnfStateChange and NtWaitForWnfStateChange from NtDll
NtSubscribeWnfStateChange_t NtSubscribeWnfStateChangePtr = NULL;
NtWaitForWnfStateChange_t NtWaitForWnfStateChangePtr = NULL;
// Function to dynamically load the required Nt functions
bool LoadNtFunctions()
{
HMODULE hNtDll = GetModuleHandleW(L"ntdll.dll");
if (!hNtDll) {
std::cerr << "Failed to get handle to ntdll.dll" << std::endl;
return false;
}
NtSubscribeWnfStateChangePtr = (NtSubscribeWnfStateChange_t)GetProcAddress(hNtDll, "NtSubscribeWnfStateChange");
NtWaitForWnfStateChangePtr = (NtWaitForWnfStateChange_t)GetProcAddress(hNtDll, "NtWaitForWnfStateChange");
if (!NtSubscribeWnfStateChangePtr || !NtWaitForWnfStateChangePtr) {
std::cerr << "Failed to get function addresses from ntdll.dll" << std::endl;
return false;
}
return true;
}
// Callback function prototype
VOID CALLBACK WnfCallback(
PVOID CallbackContext,
PVOID Buffer,
ULONG BufferSize
)
{
if (Buffer == NULL || BufferSize < sizeof(INSTRUCTIONS)) {
std::cerr << "Invalid buffer received in callback." << std::endl;
return;
}
PINSTRUCTIONS instructions = (PINSTRUCTIONS)Buffer;
std::cout << "Received WNF State Change:" << std::endl;
std::cout << "Close: " << instructions->close << std::endl;
std::cout << "Read: " << instructions->read << std::endl;
std::cout << "Request Base: " << instructions->reqBase << std::endl;
std::cout << "Buffer Address: " << instructions->bufferAddress << std::endl;
std::cout << "Address: " << std::hex << instructions->address << std::dec << std::endl;
std::cout << "Size: " << instructions->size << std::endl;
std::cout << "Output: " << instructions->output << std::endl;
std::cout << "Base Address: " << std::hex << instructions->baseAddress << std::dec << std::endl;
std::cout << "Module Name: " << instructions->moduleName << std::endl;
// Based on instructions, perform actions such as Read/Write memory
// This part requires implementing memory operations, which typically involve kernel-mode interactions
// For user-mode, you'd need to have appropriate permissions and possibly use other APIs or drivers
}
int main()
{
if (!LoadNtFunctions()) {
return -1;
}
// Prepare subscription
WNF_STATE_NAME stateName = MY_WNF_STATE_NAME;
// Define a callback context (can be NULL if not needed)
PVOID callbackContext = NULL;
// Define the callback function
// Note: WNF callbacks in user-mode are not straightforward and may require different handling
// This example uses a simplified approach
// In reality, you might need to implement a more robust callback mechanism
// Potentially using overlapped I/O or polling with NtWaitForWnfStateChange
// Since NtSubscribeWnfStateChange is not officially documented, this is a placeholder
// You might need to implement polling with NtWaitForWnfStateChange instead
// Example polling loop
std::cout << "Subscribing to WNF State Change..." << std::endl;
while (true) {
WNF_CHANGE_STAMP changeStamp = 0;
INSTRUCTIONS instructions = { 0 };
ULONG bytesReturned = 0;
NTSTATUS status = NtWaitForWnfStateChangePtr(
&changeStamp,
stateName,
NULL, // MatchAnyValue
0, // MatchAnyLength
NULL, // MatchAllValue
0, // MatchAllLength
NULL, // Timeout (NULL for infinite)
&instructions,
sizeof(INSTRUCTIONS),
&bytesReturned
);
if (NT_SUCCESS(status)) {
WnfCallback(NULL, &instructions, bytesReturned);
}
else {
std::cerr << "NtWaitForWnfStateChange failed with status: 0x" << std::hex << status << std::dec << std::endl;
break;
}
// Sleep or wait as necessary
std::this_thread::sleep_for(std::chrono::milliseconds(100));
}
return 0;
}
```
### **Explanation of the Code:**
1. **Structure Definition:**
- The `INSTRUCTIONS` structure is defined to match the driver's structure. Adjust the `moduleName` size as per actual usage.
2. **Dynamic Loading of Nt Functions:**
- Since WNF APIs are undocumented, the code dynamically loads `NtSubscribeWnfStateChange` and `NtWaitForWnfStateChange` from `ntdll.dll`. Ensure these functions are available; otherwise, you might need to implement alternative methods.
3. **Callback Implementation:**
- The `WnfCallback` function processes the received `INSTRUCTIONS`. This function is called whenever the WNF state changes.
- **Note:** Implementing actual callback mechanisms for WNF in user-mode is complex due to the lack of official documentation. This example uses a polling approach with `NtWaitForWnfStateChange`.
4. **Subscription Loop:**
- The `main` function enters an infinite loop, waiting for WNF state changes using `NtWaitForWnfStateChange`.
- Upon receiving a state change, it calls the `WnfCallback` to handle the instructions.
5. **Memory Operations:**
- Performing actual read/write operations based on the received instructions would require additional implementations, possibly involving other APIs or drivers. This example focuses on receiving and handling the instructions.
### **Compiling the Code:**
1. **Environment:**
- Use a Windows development environment with appropriate SDKs.
- Ensure that you have administrative privileges to run the application, as interacting with WNF and kernel-mode drivers typically requires elevated rights.
2. **Compiler Settings:**
- Use a C++ compiler (e.g., Visual Studio) to compile the code.
- Link against necessary libraries, though in this example, dynamic loading is used to avoid dependencies.
3. **Error Handling:**
- The example includes basic error handling. For production code, implement more robust error checking and handling mechanisms.
### **Alternative Approach Using NtApiDotNet (Managed Code):**
If you're open to using **C#** and managed code, the [NtApiDotNet](https://github.com/TheWover/NtApiDotNet) library simplifies interacting with WNF and other Nt APIs. Here's a brief example using C#:
```csharp
using System;
using NtApiDotNet;
using System.Threading;
namespace WnfSubscriber
{
class Program
{
// Define the WNF state name
private const ulong MY_WNF_STATE_NAME = 0x41C64E6DA3BC1074;
static void Main(string[] args)
{
WnfClient client = new WnfClient();
// Subscribe to the WNF state
client.SubscribeState(MY_WNF_STATE_NAME, OnWnfStateChange);
Console.WriteLine("Subscribed to WNF state. Waiting for changes...");
// Keep the application running
while (true)
{
Thread.Sleep(1000);
}
}
// Callback when WNF state changes
static void OnWnfStateChange(WnfStateChange change)
{
Console.WriteLine("WNF State Changed!");
// Assuming the state data is the INSTRUCTIONS structure
// Deserialize the data accordingly
if (change.Data.Length >= Marshal.SizeOf(typeof(INSTRUCTIONS)))
{
INSTRUCTIONS instructions = change.Data.ToStructure<INSTRUCTIONS>();
Console.WriteLine("Received Instructions:");
Console.WriteLine($"Close: {instructions.close}");
Console.WriteLine($"Read: {instructions.read}");
Console.WriteLine($"Request Base: {instructions.reqBase}");
Console.WriteLine($"Buffer Address: {instructions.bufferAddress}");
Console.WriteLine($"Address: 0x{instructions.address:X}");
Console.WriteLine($"Size: {instructions.size}");
Console.WriteLine($"Output: {instructions.output}");
Console.WriteLine($"Base Address: 0x{instructions.baseAddress:X}");
Console.WriteLine($"Module Name: {instructions.moduleName}");
}
else
{
Console.WriteLine("Received data is smaller than expected.");
}
}
// Define the INSTRUCTIONS structure
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
struct INSTRUCTIONS
{
public byte close;
public byte read;
public byte reqBase;
public IntPtr bufferAddress;
public UIntPtr address;
public ulong size;
public IntPtr output;
public ulong baseAddress;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 256)]
public string moduleName;
}
}
}
```
**Notes:**
- **NtApiDotNet Library:** This example uses the `NtApiDotNet` library to interact with WNF. Install it via NuGet:
```
Install-Package NtApiDotNet
```
- **Structure Alignment:** Ensure that the `INSTRUCTIONS` structure in C# matches the one in the driver, paying attention to packing and alignment.
- **Permissions:** Running this application might require Administrator privileges.
- **Handling Data:** Properly handle the received data to perform desired operations, considering security and stability.
### **Final Remarks:**
Interacting with WNF from user-mode applications is an advanced topic due to the lack of official documentation and support. The examples provided offer a starting point, but you'll need to adjust and expand them based on your specific requirements and the behavior of the kernel-mode driver.
**Recommendation:** If possible, consider implementing a more straightforward communication mechanism between the user-mode application and the driver, such as **IOCTLs** via a device interface. This approach is more stable, documented, and easier to maintain.