public override IntPtr[] InjectAll(string[] dllPaths, IntPtr hProcess)
{
ClearErrors();
if (hProcess.IsNull() || hProcess.Compare(-1))
throw new ArgumentOutOfRangeException("hProcess", "Invalid process handle specified.");
try
{
// Use the optimized assembly "multiload" stub to load all the dlls in one go.
IntPtr pModules = IntPtr.Zero;
IntPtr pStub = CreateMultiLoadStub(dllPaths, hProcess, out pModules);
IntPtr[] modules = null;
if (!pStub.IsNull())
{
try
{
// Run the stub
uint threadval = WinAPI.RunThread(hProcess, pStub, 0, 10000);
if (threadval != uint.MaxValue)
{
// Read the module handle buffer into memory
byte[] rawHandles = WinAPI.ReadRemoteMemory(hProcess, pModules, (uint)dllPaths.Length << 2);
if (rawHandles != null)
{
// convert the raw binary data into usable module handles.
modules = new IntPtr[dllPaths.Length];
for (int i = 0; i < modules.Length; i++)
modules[i] = new IntPtr(BitConverter.ToInt32(rawHandles, i << 2));
}
else
{
throw new InvalidOperationException("Unable to read from the remote process.");
}
}
else
{
throw new Exception("Error occurred while executing remote thread.");
}
}
finally
{
// cleanup the memory
WinAPI.VirtualFreeEx(hProcess, pModules, 0, 0x8000);
WinAPI.VirtualFreeEx(hProcess, pStub, 0, 0x8000);
}
}
return modules;
}
catch (Exception e)
{
SetLastError(e);
return null;
}
}
// Core injection method that actually does all the work.
public override IntPtr Inject(string dllPath, IntPtr hProcess)
{
ClearErrors();
if (hProcess.IsNull() || hProcess.Compare(-1))
throw new ArgumentOutOfRangeException("hProcess", "Invalid process handle specified.");
try
{
IntPtr hModule = IntPtr.Zero;
// Find the LoadLibraryW function address in the remote process
IntPtr fnLoadLibraryW = WinAPI.GetProcAddress(WinAPI.GetModuleHandleA("kernel32.dll"), "LoadLibraryW");
if (fnLoadLibraryW.IsNull())
throw new Exception("Unable to locate the LoadLibraryW entry point");
// Create a wchar_t * in the remote process which points to the unicode version of the dll path.
IntPtr pLib = WinAPI.CreateRemotePointer(hProcess, Encoding.Unicode.GetBytes(dllPath + "\0"), 0x04);
if (pLib.IsNull())
throw new InvalidOperationException("Failed to allocate memory in the remote process");
try
{
// Call LoadLibraryW in the remote process by using CreateRemoteThread.
uint hMod = WinAPI.RunThread(hProcess, fnLoadLibraryW, (uint)pLib.ToInt32(), 10000);
if (hMod == uint.MaxValue)
throw new Exception("Error occurred when calling function in the remote process");
else if (hMod == 0)
throw new Exception("Failed to load module into remote process. Error code: " + WinAPI.GetLastErrorEx(hProcess).ToString());
else
hModule = Win32Ptr.Create(hMod);
}
finally
{
// Cleanup in all cases.
WinAPI.VirtualFreeEx(hProcess, pLib, 0, 0x8000);
}
return hModule;
}
catch (Exception e)
{
SetLastError(e);
return IntPtr.Zero;
}
}
public override bool Unload(IntPtr hModule, IntPtr hProcess)
{
ClearErrors();
if (hProcess.IsNull() || hProcess.Compare(-1))
throw new ArgumentOutOfRangeException("hProcess", "Invalid process handle specified.");
if (hModule.IsNull())
throw new ArgumentNullException("hModule", "Invalid module handle");
try
{
bool[] results = UnloadAll(new IntPtr[] { hModule }, hProcess);
return results != null && results.Length > 0
? results[0]
: false;
}
catch (Exception e)
{
SetLastError(e);
return false;
}
}
public override bool Unload(IntPtr hModule, IntPtr hProcess)
{
// Unloading a manually mapped file is fairly straightforward. There is no need to call FreeLibrary or anything
// because the file was never actually injected using LoadLibrary and doesn't need to clear any PEB entries etc.
// basically just call the Entry Point again with DLL_PROCESS_DETACH flag and not-null for the lpReserved parameter
// and then VirtualFree the remote memory.
ClearErrors();
if (hModule.IsNull())
throw new ArgumentNullException("hModule", "Invalid module handle");
if (hProcess.IsNull() || hProcess.Compare(-1))
throw new ArgumentException("Invalid process handle.", "hProcess");
IntPtr pStub = IntPtr.Zero;
uint nBytes = 0;
try
{
uint entry = FindEntryPoint(hProcess, hModule);
if (entry != 0)
{
var stub = (byte[])DLLMAIN_STUB.Clone();
BitConverter.GetBytes(hModule.ToInt32()).CopyTo(stub, 0x0B);
BitConverter.GetBytes((uint)0).CopyTo(stub, 0x06);
BitConverter.GetBytes((uint)1000).CopyTo(stub, 0x01);
pStub = WinAPI.VirtualAllocEx(hProcess, IntPtr.Zero, (uint)DLLMAIN_STUB.Length, 0x1000 | 0x2000, 0x40);
if (pStub.IsNull() || (!WinAPI.WriteProcessMemory(hProcess, pStub, stub, stub.Length, out nBytes) || nBytes != (uint)stub.Length))
throw new InvalidOperationException("Unable to write stub to the remote process.");
IntPtr hStubThread = WinAPI.CreateRemoteThread(hProcess, 0, 0, pStub, (uint)hModule.Add(entry).ToInt32(), 0, 0);
if (WinAPI.WaitForSingleObject(hStubThread, 5000) == 0x0L)
{
WinAPI.VirtualFreeEx(hProcess, pStub, 0, 0x8000);
WinAPI.CloseHandle(hStubThread);
return WinAPI.VirtualFreeEx(hProcess, hModule, 0, 0x8000);
}
return false;
}
else
{
return WinAPI.VirtualFreeEx(hProcess, hModule, 0, 0x8000);
}
}
catch (Exception e)
{
SetLastError(e);
return false;
}
}
/**
* Find the entry point of a loaded module
* based on its Base Address. Reverses the PE
* structure to find the entry point
*/
private static uint FindEntryPoint(IntPtr hProcess, IntPtr hModule)
{
if (hProcess.IsNull() || hProcess.Compare(-1))
throw new ArgumentException("Invalid process handle.", "hProcess");
if (hModule.IsNull())
throw new ArgumentException("Invalid module handle.", "hModule");
byte[] bDosHeader = WinAPI.ReadRemoteMemory(hProcess, hModule, (uint)Marshal.SizeOf(typeof(IMAGE_DOS_HEADER)));
if (bDosHeader != null)
{
ushort e_magic = BitConverter.ToUInt16(bDosHeader, 0);
uint e_lfanew = BitConverter.ToUInt32(bDosHeader, 0x3C);
if (e_magic == 23117)
{
byte[] bNtHeader = WinAPI.ReadRemoteMemory(hProcess, hModule.Add(e_lfanew), (uint)Marshal.SizeOf(typeof(IMAGE_NT_HEADER32)));
if (bNtHeader != null && BitConverter.ToUInt32(bNtHeader, 0) == 17744)
{
IMAGE_NT_HEADER32 ntHd = default(IMAGE_NT_HEADER32);
using (var buffer = new UnmanagedBuffer(256))
if (buffer.Translate<IMAGE_NT_HEADER32>(bNtHeader, out ntHd))
return ntHd.OptionalHeader.AddressOfEntryPoint;
}
}
}
return 0;
}
// Most efficient version, this will be the work horse.
private static IntPtr MapModule(PortableExecutable image, IntPtr hProcess, bool preserveHeaders = false)
{
if (hProcess.IsNull() || hProcess.Compare(-1))
throw new ArgumentException("Invalid process handle.", "hProcess");
if (image == null)
throw new ArgumentException("Cannot map a non-existant PE Image.", "image");
int processId = WinAPI.GetProcessId(hProcess);
if (processId == 0)
throw new ArgumentException("Provided handle doesn't have sufficient permissions to inject", "hProcess");
IntPtr hModule = IntPtr.Zero;
IntPtr pStub = IntPtr.Zero;
uint nBytes = 0;
try
{
//allocate memory for the image to load into the remote process.
hModule = WinAPI.VirtualAllocEx(hProcess, IntPtr.Zero, image.NTHeader.OptionalHeader.SizeOfImage, 0x1000 | 0x2000, 0x04);
if (hModule.IsNull())
throw new InvalidOperationException("Unable to allocate memory in the remote process.");
PatchRelocations(image, hModule);
LoadDependencies(image, hProcess, processId);
PatchImports(image, hProcess, processId);
if (preserveHeaders)
{
long szHeader = (image.DOSHeader.e_lfanew + Marshal.SizeOf(typeof(IMAGE_FILE_HEADER)) + sizeof(uint) + image.NTHeader.FileHeader.SizeOfOptionalHeader);
byte[] header = new byte[szHeader];
if (image.Read(0, SeekOrigin.Begin, header))
WinAPI.WriteProcessMemory(hProcess, hModule, header, header.Length, out nBytes);
}
MapSections(image, hProcess, hModule);
// some modules don't have an entry point and are purely libraries, mapping them and keeping the handle is just fine
// an unlikely scenario with forced injection, but you never know.
if (image.NTHeader.OptionalHeader.AddressOfEntryPoint > 0)
{
var stub = (byte[])DLLMAIN_STUB.Clone();
BitConverter.GetBytes(hModule.ToInt32()).CopyTo(stub, 0x0B);
pStub = WinAPI.VirtualAllocEx(hProcess, IntPtr.Zero, (uint)DLLMAIN_STUB.Length, 0x1000 | 0x2000, 0x40);
if (pStub.IsNull() || (!WinAPI.WriteProcessMemory(hProcess, pStub, stub, stub.Length, out nBytes) || nBytes != (uint)stub.Length))
throw new InvalidOperationException("Unable to write stub to the remote process.");
IntPtr hStubThread = WinAPI.CreateRemoteThread(hProcess, 0, 0, pStub, (uint)(hModule.Add(image.NTHeader.OptionalHeader.AddressOfEntryPoint).ToInt32()), 0, 0);
if (WinAPI.WaitForSingleObject(hStubThread, 5000) == 0x0L)
{
WinAPI.GetExitCodeThread(hStubThread, out nBytes);
if (nBytes == 0)
{
WinAPI.VirtualFreeEx(hProcess, hModule, 0, 0x8000);
throw new Exception("Entry method of module reported a failure " + Marshal.GetLastWin32Error().ToString());
}
WinAPI.VirtualFreeEx(hProcess, pStub, 0, 0x8000);
WinAPI.CloseHandle(hStubThread);
}
}
}
catch (Exception e)
{
if (!hModule.IsNull())
WinAPI.VirtualFreeEx(hProcess, hModule, 0, 0x8000);
if (!pStub.IsNull())
WinAPI.VirtualFreeEx(hProcess, hModule, 0, 0x8000);
hModule = IntPtr.Zero;
throw e;
}
return hModule;
}
public override bool[] UnloadAll(IntPtr[] hModules, IntPtr hProcess)
{
// No fancy optimized method here, UnloadAll simply represents a series of direct calls to Unload for each
// module. Pretty simple stuff.
ClearErrors();
if (hModules == null)
throw new ArgumentNullException("hModules", "Parameter cannot be null.");
if (hProcess.IsNull() || hProcess.Compare(-1))
throw new ArgumentOutOfRangeException("hProcess", "Invalid process handle specified.");
try
{
var results = new bool[hModules.Length];
for (int i = 0; i < hModules.Length; i++)
results[i] = Unload(hModules[i], hProcess);
return results;
}
catch (Exception e)
{
SetLastError(e);
return null;
}
}
public override IntPtr[] InjectAll(string[] dllPaths, IntPtr hProcess)
{
ClearErrors();
try
{
if (hProcess.IsNull() || hProcess.Compare(-1))
throw new ArgumentException("Invalid process handle.", "hProcess");
int processId = WinAPI.GetProcessId(hProcess);
if (processId == 0)
throw new ArgumentException("Provided handle doesn't have sufficient permissions to inject", "hProcess");
Process target = Process.GetProcessById(processId);
if (target.Threads.Count == 0)
throw new Exception("Target process has no targetable threads to hijack.");
//open a handle to the remote thread to allow for thread operations.
ProcessThread thread = SelectOptimalThread(target);
IntPtr hThread = WinAPI.OpenThread(0x001A, false, thread.Id);
if (hThread.IsNull() || hThread.Compare(-1))
throw new Exception("Unable to obtain a handle for the remote thread.");
IntPtr pModules = IntPtr.Zero;
IntPtr pRedirect = IntPtr.Zero;
// use the generic multiload stub to load the paths.
// call this stub from the REDIRECT_STUB.
IntPtr pStub = CreateMultiLoadStub(dllPaths, hProcess, out pModules, 1);
IntPtr[] modules = null;
if (!pStub.IsNull())
{
if (WinAPI.SuspendThread(hThread) == uint.MaxValue)
throw new Exception("Unable to suspend the remote thread");
//enter a new try/catch block to ensure the suspended thread is resumed, no matter if we fail somewhere else.
try
{
uint nbytes = 0;
WinAPI.CONTEXT ctx = default(WinAPI.CONTEXT);
ctx.ContextFlags = 0x10001U; // CONTEXT_CONTROL flag. So that we get back the EIP value of the suspended thread.
if (!WinAPI.GetThreadContext(hThread, ref ctx))
throw new InvalidOperationException("Cannot get the remote thread's context");
byte[] stub = REDIRECT_STUB;
IntPtr pAlloc = WinAPI.VirtualAllocEx(hProcess, IntPtr.Zero, (uint)stub.Length, 0x1000 | 0x2000, 0x40);
if (pAlloc.IsNull())
throw new InvalidOperationException("Unable to allocate memory in the remote process.");
//patch the EIP value and the Stub address for the redirection stub before commiting it to the remote process.
BitConverter.GetBytes(pStub.Subtract(pAlloc.Add(7)).ToInt32()).CopyTo(stub, 3);
BitConverter.GetBytes((uint)(ctx.Eip - pAlloc.Add(stub.Length).ToInt32())).CopyTo(stub, stub.Length - 4);
if (!WinAPI.WriteProcessMemory(hProcess, pAlloc, stub, stub.Length, out nbytes) || nbytes != (uint)stub.Length)
throw new InvalidOperationException("Unable to write stub to the remote process.");
ctx.Eip = (uint)pAlloc.ToInt32(); // Set the entry point for the thread to the redirection stub and resume the thread.
WinAPI.SetThreadContext(hThread, ref ctx);
}
catch (Exception e)
{
SetLastError(e);
modules = null;
WinAPI.VirtualFreeEx(hProcess, pModules, 0, 0x8000);
WinAPI.VirtualFreeEx(hProcess, pStub, 0, 0x8000);
WinAPI.VirtualFreeEx(hProcess, pRedirect, 0, 0x8000);
}
WinAPI.ResumeThread(hThread);
if (GetLastError() == null)
{
System.Threading.Thread.Sleep(100);
modules = new IntPtr[dllPaths.Length];
byte[] rawHandles = WinAPI.ReadRemoteMemory(hProcess, pModules, (uint)dllPaths.Length << 2);
if (rawHandles != null)
{
for (int i = 0; i < modules.Length; i++)
modules[i] = Win32Ptr.Create(BitConverter.ToInt32(rawHandles, i << 2));
}
}
// deliberately didn't clean up the remote memory here. Unfortunately there's no solid way
// to ensure the function stub has been scheduled by the operating system. It may not even happen for
// ages, or something else may block the thread. When the stub eventually is executes and returns, the reset
// of the stub needs to still be there in order for the function to successfully return, otherwise the process just crashes
// and we lose the distinct possibility that the injection was successful.
WinAPI.CloseHandle(hThread);
}
return modules;
}
catch (Exception e)
{
SetLastError(e);
return null;
}
}