/// <summary>
/// Call a manually mapped DLL by Export.
/// </summary>
/// <author>Ruben Boonen (@FuzzySec)</author>
/// <param name="PEINFO">Module meta data struct (PE.PE_META_DATA).</param>
/// <param name="ModuleMemoryBase">Base address of the module in memory.</param>
/// <param name="ExportName">The name of the export to search for (e.g. "NtAlertResumeThread").</param>
/// <param name="FunctionDelegateType">Prototype for the function, represented as a Delegate object.</param>
/// <param name="Parameters">Arbitrary set of parameters to pass to the function. Can be modified if function uses call by reference.</param>
/// <returns>void</returns>
public static object CallMappedDLLModuleExport(PE.PE_META_DATA PEINFO, IntPtr ModuleMemoryBase, string ExportName, Type FunctionDelegateType, object[] Parameters)
{
CallMappedDLLModule(PEINFO, ModuleMemoryBase);
// Get export pointer
IntPtr pFunc = GetExportAddress(ModuleMemoryBase, ExportName);
// Call export
return(DynamicFunctionInvoke(pFunc, FunctionDelegateType, ref Parameters));
}
/// <summary>
/// Call a manually mapped DLL by DllMain -> DLL_PROCESS_ATTACH.
/// </summary>
/// <author>Ruben Boonen (@FuzzySec)</author>
/// <param name="PEINFO">Module meta data struct (PE.PE_META_DATA).</param>
/// <param name="ModuleMemoryBase">Base address of the module in memory.</param>
/// <returns>void</returns>
public static void CallMappedDLLModule(PE.PE_META_DATA PEINFO, IntPtr ModuleMemoryBase)
{
IntPtr lpEntryPoint = PEINFO.Is32Bit ? (IntPtr)((UInt64)ModuleMemoryBase + PEINFO.OptHeader32.AddressOfEntryPoint) :
(IntPtr)((UInt64)ModuleMemoryBase + PEINFO.OptHeader64.AddressOfEntryPoint);
PE.DllMain fDllMain = (PE.DllMain)Marshal.GetDelegateForFunctionPointer(lpEntryPoint, typeof(PE.DllMain));
bool CallRes = fDllMain(ModuleMemoryBase, PE.DLL_PROCESS_ATTACH, IntPtr.Zero);
if (!CallRes)
{
throw new InvalidOperationException("Failed to call DllMain -> DLL_PROCESS_ATTACH");
}
}
/// <summary>
/// Call a manually mapped PE by its EntryPoint.
/// </summary>
/// <author>Ruben Boonen (@FuzzySec)</author>
/// <param name="PEINFO">Module meta data struct (PE.PE_META_DATA).</param>
/// <param name="ModuleMemoryBase">Base address of the module in memory.</param>
/// <returns>void</returns>
public static void CallMappedPEModule(PE.PE_META_DATA PEINFO, IntPtr ModuleMemoryBase)
{
// Call module by EntryPoint (eg Mimikatz.exe)
IntPtr hRemoteThread = IntPtr.Zero;
IntPtr lpStartAddress = PEINFO.Is32Bit ? (IntPtr)((UInt64)ModuleMemoryBase + PEINFO.OptHeader32.AddressOfEntryPoint) :
(IntPtr)((UInt64)ModuleMemoryBase + PEINFO.OptHeader64.AddressOfEntryPoint);
Native.NtCreateThreadEx(
ref hRemoteThread,
Execute.Win32.WinNT.ACCESS_MASK.STANDARD_RIGHTS_ALL,
IntPtr.Zero, (IntPtr)(-1),
lpStartAddress, IntPtr.Zero,
false, 0, 0, 0, IntPtr.Zero
);
}
/// <summary>
/// Retrieve PE header information from the module base pointer.
/// </summary>
/// <author>Ruben Boonen (@FuzzySec)</author>
/// <param name="pModule">Pointer to the module base.</param>
/// <returns>PE.PE_META_DATA</returns>
public static PE.PE_META_DATA GetPeMetaData(IntPtr pModule)
{
PE.PE_META_DATA PeMetaData = new PE.PE_META_DATA();
try
{
UInt32 e_lfanew = (UInt32)Marshal.ReadInt32((IntPtr)((UInt64)pModule + 0x3c));
PeMetaData.Pe = (UInt32)Marshal.ReadInt32((IntPtr)((UInt64)pModule + e_lfanew));
// Validate PE signature
if (PeMetaData.Pe != 0x4550)
{
throw new InvalidOperationException("Invalid PE signature.");
}
PeMetaData.ImageFileHeader = (PE.IMAGE_FILE_HEADER)Marshal.PtrToStructure((IntPtr)((UInt64)pModule + e_lfanew + 0x4), typeof(PE.IMAGE_FILE_HEADER));
IntPtr OptHeader = (IntPtr)((UInt64)pModule + e_lfanew + 0x18);
UInt16 PEArch = (UInt16)Marshal.ReadInt16(OptHeader);
// Validate PE arch
if (PEArch == 0x010b) // Image is x32
{
PeMetaData.Is32Bit = true;
PeMetaData.OptHeader32 = (PE.IMAGE_OPTIONAL_HEADER32)Marshal.PtrToStructure(OptHeader, typeof(PE.IMAGE_OPTIONAL_HEADER32));
}
else if (PEArch == 0x020b) // Image is x64
{
PeMetaData.Is32Bit = false;
PeMetaData.OptHeader64 = (PE.IMAGE_OPTIONAL_HEADER64)Marshal.PtrToStructure(OptHeader, typeof(PE.IMAGE_OPTIONAL_HEADER64));
}
else
{
throw new InvalidOperationException("Invalid magic value (PE32/PE32+).");
}
// Read sections
PE.IMAGE_SECTION_HEADER[] SectionArray = new PE.IMAGE_SECTION_HEADER[PeMetaData.ImageFileHeader.NumberOfSections];
for (int i = 0; i < PeMetaData.ImageFileHeader.NumberOfSections; i++)
{
IntPtr SectionPtr = (IntPtr)((UInt64)OptHeader + PeMetaData.ImageFileHeader.SizeOfOptionalHeader + (UInt32)(i * 0x28));
SectionArray[i] = (PE.IMAGE_SECTION_HEADER)Marshal.PtrToStructure(SectionPtr, typeof(PE.IMAGE_SECTION_HEADER));
}
PeMetaData.Sections = SectionArray;
}
catch
{
throw new InvalidOperationException("Invalid module base specified.");
}
return(PeMetaData);
}
/// <summary>
/// Read ntdll from disk, find/copy the appropriate syscall stub and free ntdll.
/// </summary>
/// <author>Ruben Boonen (@FuzzySec)</author>
/// <param name="FunctionName">The name of the function to search for (e.g. "NtAlertResumeThread").</param>
/// <returns>IntPtr, Syscall stub</returns>
public static IntPtr GetSyscallStub(string FunctionName)
{
// Verify process & architecture
bool isWOW64 = Native.NtQueryInformationProcessWow64Information((IntPtr)(-1));
if (IntPtr.Size == 4 && isWOW64)
{
throw new InvalidOperationException("Generating Syscall stubs is not supported for WOW64.");
}
// Find the path for ntdll by looking at the currently loaded module
string NtdllPath = string.Empty;
ProcessModuleCollection ProcModules = Process.GetCurrentProcess().Modules;
foreach (ProcessModule Mod in ProcModules)
{
if (Mod.FileName.EndsWith("ntdll.dll", StringComparison.OrdinalIgnoreCase))
{
NtdllPath = Mod.FileName;
}
}
// Alloc module into memory for parsing
IntPtr pModule = Execute.ManualMap.Map.AllocateFileToMemory(NtdllPath);
// Fetch PE meta data
PE.PE_META_DATA PEINFO = GetPeMetaData(pModule);
// Alloc PE image memory -> RW
IntPtr BaseAddress = IntPtr.Zero;
IntPtr RegionSize = PEINFO.Is32Bit ? (IntPtr)PEINFO.OptHeader32.SizeOfImage : (IntPtr)PEINFO.OptHeader64.SizeOfImage;
UInt32 SizeOfHeaders = PEINFO.Is32Bit ? PEINFO.OptHeader32.SizeOfHeaders : PEINFO.OptHeader64.SizeOfHeaders;
IntPtr pImage = Native.NtAllocateVirtualMemory(
(IntPtr)(-1), ref BaseAddress, IntPtr.Zero, ref RegionSize,
Execute.Win32.Kernel32.MEM_COMMIT | Execute.Win32.Kernel32.MEM_RESERVE,
Execute.Win32.WinNT.PAGE_READWRITE
);
// Write PE header to memory
UInt32 BytesWritten = Native.NtWriteVirtualMemory((IntPtr)(-1), pImage, pModule, SizeOfHeaders);
// Write sections to memory
foreach (PE.IMAGE_SECTION_HEADER ish in PEINFO.Sections)
{
// Calculate offsets
IntPtr pVirtualSectionBase = (IntPtr)((UInt64)pImage + ish.VirtualAddress);
IntPtr pRawSectionBase = (IntPtr)((UInt64)pModule + ish.PointerToRawData);
// Write data
BytesWritten = Native.NtWriteVirtualMemory((IntPtr)(-1), pVirtualSectionBase, pRawSectionBase, ish.SizeOfRawData);
if (BytesWritten != ish.SizeOfRawData)
{
throw new InvalidOperationException("Failed to write to memory.");
}
}
// Get Ptr to function
IntPtr pFunc = GetExportAddress(pImage, FunctionName);
if (pFunc == IntPtr.Zero)
{
throw new InvalidOperationException("Failed to resolve ntdll export.");
}
// Alloc memory for call stub
BaseAddress = IntPtr.Zero;
RegionSize = (IntPtr)0x50;
IntPtr pCallStub = Native.NtAllocateVirtualMemory(
(IntPtr)(-1), ref BaseAddress, IntPtr.Zero, ref RegionSize,
Execute.Win32.Kernel32.MEM_COMMIT | Execute.Win32.Kernel32.MEM_RESERVE,
Execute.Win32.WinNT.PAGE_READWRITE
);
// Write call stub
BytesWritten = Native.NtWriteVirtualMemory((IntPtr)(-1), pCallStub, pFunc, 0x50);
if (BytesWritten != 0x50)
{
throw new InvalidOperationException("Failed to write to memory.");
}
// Change call stub permissions
Native.NtProtectVirtualMemory((IntPtr)(-1), ref pCallStub, ref RegionSize, Execute.Win32.WinNT.PAGE_EXECUTE_READ);
// Free temporary allocations
Marshal.FreeHGlobal(pModule);
RegionSize = PEINFO.Is32Bit ? (IntPtr)PEINFO.OptHeader32.SizeOfImage : (IntPtr)PEINFO.OptHeader64.SizeOfImage;
Native.NtFreeVirtualMemory((IntPtr)(-1), ref pImage, ref RegionSize, Execute.Win32.Kernel32.MEM_RELEASE);
return(pCallStub);
}