Using the topic Overview - Handle Enumeration, number 5, the attempt Close mutex of another process and and information from Mutex analysis, the canary in the coal mine and discovering new families of malware/, I have came up with:
Attempt 1: http://pastebin.com/QU0WBgE5
You must open Notepad first. Needless to say, this is not working for me. I need better error checking to figure out what's going on. I don't know how to get mutex pointers in the format I see them in Process Explorer.
My goal is to be able to delete/kill of the mutex handles created by a process so more than one instance can be open. I can do this manually using Process Explorer, but I want to do it programmatically.
(Based on Yahia's notes, I need more permissions.)
Attempt 2: http://pastebin.com/yyQLhesP
At least now I have some sort of error checking, most of the time DuplicateHandle returns 6 or 5, which is an invalid handle and access denied respectfully.
Working attempt (kind of):
I actually didn't require anything Yahia stated in the end. I was getting a "local" handle when I needed a remote one. Basically, what I mean is that you have to find the HandleValue using NtQuerySystemInformation and use that handle, not the one returned by OpenMutex / CreateMutex.
Granted, I can't get it to work on some applications (osk.exe -- on screen keyboard), but it worked for the application I was going for, posting code in case someone wants to take it further.
using System;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using System.Diagnostics;
using System.Text;
using System.Threading;
using System.Security.AccessControl;
using System.Security.Principal;
namespace FileLockInfo
{
public class Win32API
{
[DllImport("ntdll.dll")]
public static extern int NtQueryObject(IntPtr ObjectHandle, int
ObjectInformationClass, IntPtr ObjectInformation, int ObjectInformationLength,
ref int returnLength);
[DllImport("kernel32.dll", SetLastError = true)]
public static extern uint QueryDosDevice(string lpDeviceName, StringBuilder lpTargetPath, int ucchMax);
[DllImport("ntdll.dll")]
public static extern uint NtQuerySystemInformation(int
SystemInformationClass, IntPtr SystemInformation, int SystemInformationLength,
ref int returnLength);
[DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
public static extern IntPtr OpenMutex(UInt32 desiredAccess, bool inheritHandle, string name);
[DllImport("kernel32.dll")]
public static extern IntPtr OpenProcess(ProcessAccessFlags dwDesiredAccess, [MarshalAs(UnmanagedType.Bool)] bool bInheritHandle, int dwProcessId);
[DllImport("kernel32.dll")]
public static extern int CloseHandle(IntPtr hObject);
[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
public static extern bool DuplicateHandle(IntPtr hSourceProcessHandle,
ushort hSourceHandle, IntPtr hTargetProcessHandle, out IntPtr lpTargetHandle,
uint dwDesiredAccess, [MarshalAs(UnmanagedType.Bool)] bool bInheritHandle, uint dwOptions);
[DllImport("kernel32.dll")]
public static extern IntPtr GetCurrentProcess();
public enum ObjectInformationClass : int
{
ObjectBasicInformation = 0,
ObjectNameInformation = 1,
ObjectTypeInformation = 2,
ObjectAllTypesInformation = 3,
ObjectHandleInformation = 4
}
[Flags]
public enum ProcessAccessFlags : uint
{
All = 0x001F0FFF,
Terminate = 0x00000001,
CreateThread = 0x00000002,
VMOperation = 0x00000008,
VMRead = 0x00000010,
VMWrite = 0x00000020,
DupHandle = 0x00000040,
SetInformation = 0x00000200,
QueryInformation = 0x00000400,
Synchronize = 0x00100000
}
[StructLayout(LayoutKind.Sequential)]
public struct OBJECT_BASIC_INFORMATION
{ // Information Class 0
public int Attributes;
public int GrantedAccess;
public int HandleCount;
public int PointerCount;
public int PagedPoolUsage;
public int NonPagedPoolUsage;
public int Reserved1;
public int Reserved2;
public int Reserved3;
public int NameInformationLength;
public int TypeInformationLength;
public int SecurityDescriptorLength;
public System.Runtime.InteropServices.ComTypes.FILETIME CreateTime;
}
[StructLayout(LayoutKind.Sequential)]
public struct OBJECT_TYPE_INFORMATION
{ // Information Class 2
public UNICODE_STRING Name;
public int ObjectCount;
public int HandleCount;
public int Reserved1;
public int Reserved2;
public int Reserved3;
public int Reserved4;
public int PeakObjectCount;
public int PeakHandleCount;
public int Reserved5;
public int Reserved6;
public int Reserved7;
public int Reserved8;
public int InvalidAttributes;
public GENERIC_MAPPING GenericMapping;
public int ValidAccess;
public byte Unknown;
public byte MaintainHandleDatabase;
public int PoolType;
public int PagedPoolUsage;
public int NonPagedPoolUsage;
}
[StructLayout(LayoutKind.Sequential)]
public struct OBJECT_NAME_INFORMATION
{ // Information Class 1
public UNICODE_STRING Name;
}
[StructLayout(LayoutKind.Sequential, Pack = 1)]
public struct UNICODE_STRING
{
public ushort Length;
public ushort MaximumLength;
public IntPtr Buffer;
}
[StructLayout(LayoutKind.Sequential)]
public struct GENERIC_MAPPING
{
public int GenericRead;
public int GenericWrite;
public int GenericExecute;
public int GenericAll;
}
[StructLayout(LayoutKind.Sequential, Pack = 1)]
public struct SYSTEM_HANDLE_INFORMATION
{ // Information Class 16
public int ProcessID;
public byte ObjectTypeNumber;
public byte Flags; // 0x01 = PROTECT_FROM_CLOSE, 0x02 = INHERIT
public ushort Handle;
public int Object_Pointer;
public UInt32 GrantedAccess;
}
public const int MAX_PATH = 260;
public const uint STATUS_INFO_LENGTH_MISMATCH = 0xC0000004;
public const int DUPLICATE_SAME_ACCESS = 0x2;
public const int DUPLICATE_CLOSE_SOURCE = 0x1;
}
public class Win32Processes
{
const int CNST_SYSTEM_HANDLE_INFORMATION = 16;
const uint STATUS_INFO_LENGTH_MISMATCH = 0xc0000004;
public static string getObjectTypeName(Win32API.SYSTEM_HANDLE_INFORMATION shHandle, Process process)
{
IntPtr m_ipProcessHwnd = Win32API.OpenProcess(Win32API.ProcessAccessFlags.All, false, process.Id);
IntPtr ipHandle = IntPtr.Zero;
var objBasic = new Win32API.OBJECT_BASIC_INFORMATION();
IntPtr ipBasic = IntPtr.Zero;
var objObjectType = new Win32API.OBJECT_TYPE_INFORMATION();
IntPtr ipObjectType = IntPtr.Zero;
IntPtr ipObjectName = IntPtr.Zero;
string strObjectTypeName = "";
int nLength = 0;
int nReturn = 0;
IntPtr ipTemp = IntPtr.Zero;
if (!Win32API.DuplicateHandle(m_ipProcessHwnd, shHandle.Handle,
Win32API.GetCurrentProcess(), out ipHandle,
0, false, Win32API.DUPLICATE_SAME_ACCESS))
return null;
ipBasic = Marshal.AllocHGlobal(Marshal.SizeOf(objBasic));
Win32API.NtQueryObject(ipHandle, (int)Win32API.ObjectInformationClass.ObjectBasicInformation,
ipBasic, Marshal.SizeOf(objBasic), ref nLength);
objBasic = (Win32API.OBJECT_BASIC_INFORMATION)Marshal.PtrToStructure(ipBasic, objBasic.GetType());
Marshal.FreeHGlobal(ipBasic);
ipObjectType = Marshal.AllocHGlobal(objBasic.TypeInformationLength);
nLength = objBasic.TypeInformationLength;
while ((uint)(nReturn = Win32API.NtQueryObject(
ipHandle, (int)Win32API.ObjectInformationClass.ObjectTypeInformation, ipObjectType,
nLength, ref nLength)) ==
Win32API.STATUS_INFO_LENGTH_MISMATCH)
{
Marshal.FreeHGlobal(ipObjectType);
ipObjectType = Marshal.AllocHGlobal(nLength);
}
objObjectType = (Win32API.OBJECT_TYPE_INFORMATION)Marshal.PtrToStructure(ipObjectType, objObjectType.GetType());
if (Is64Bits())
{
ipTemp = new IntPtr(Convert.ToInt64(objObjectType.Name.Buffer.ToString(), 10) >> 32);
}
else
{
ipTemp = objObjectType.Name.Buffer;
}
strObjectTypeName = Marshal.PtrToStringUni(ipTemp, objObjectType.Name.Length >> 1);
Marshal.FreeHGlobal(ipObjectType);
return strObjectTypeName;
}
public static string getObjectName(Win32API.SYSTEM_HANDLE_INFORMATION shHandle, Process process)
{
IntPtr m_ipProcessHwnd = Win32API.OpenProcess(Win32API.ProcessAccessFlags.All, false, process.Id);
IntPtr ipHandle = IntPtr.Zero;
var objBasic = new Win32API.OBJECT_BASIC_INFORMATION();
IntPtr ipBasic = IntPtr.Zero;
IntPtr ipObjectType = IntPtr.Zero;
var objObjectName = new Win32API.OBJECT_NAME_INFORMATION();
IntPtr ipObjectName = IntPtr.Zero;
string strObjectName = "";
int nLength = 0;
int nReturn = 0;
IntPtr ipTemp = IntPtr.Zero;
if (!Win32API.DuplicateHandle(m_ipProcessHwnd, shHandle.Handle, Win32API.GetCurrentProcess(),
out ipHandle, 0, false, Win32API.DUPLICATE_SAME_ACCESS))
return null;
ipBasic = Marshal.AllocHGlobal(Marshal.SizeOf(objBasic));
Win32API.NtQueryObject(ipHandle, (int)Win32API.ObjectInformationClass.ObjectBasicInformation,
ipBasic, Marshal.SizeOf(objBasic), ref nLength);
objBasic = (Win32API.OBJECT_BASIC_INFORMATION)Marshal.PtrToStructure(ipBasic, objBasic.GetType());
Marshal.FreeHGlobal(ipBasic);
nLength = objBasic.NameInformationLength;
ipObjectName = Marshal.AllocHGlobal(nLength);
while ((uint)(nReturn = Win32API.NtQueryObject(
ipHandle, (int)Win32API.ObjectInformationClass.ObjectNameInformation,
ipObjectName, nLength, ref nLength))
== Win32API.STATUS_INFO_LENGTH_MISMATCH)
{
Marshal.FreeHGlobal(ipObjectName);
ipObjectName = Marshal.AllocHGlobal(nLength);
}
objObjectName = (Win32API.OBJECT_NAME_INFORMATION)Marshal.PtrToStructure(ipObjectName, objObjectName.GetType());
if (Is64Bits())
{
ipTemp = new IntPtr(Convert.ToInt64(objObjectName.Name.Buffer.ToString(), 10) >> 32);
}
else
{
ipTemp = objObjectName.Name.Buffer;
}
if (ipTemp != IntPtr.Zero)
{
byte[] baTemp2 = new byte[nLength];
try
{
Marshal.Copy(ipTemp, baTemp2, 0, nLength);
strObjectName = Marshal.PtrToStringUni(Is64Bits() ?
new IntPtr(ipTemp.ToInt64()) :
new IntPtr(ipTemp.ToInt32()));
return strObjectName;
}
catch (AccessViolationException)
{
return null;
}
finally
{
Marshal.FreeHGlobal(ipObjectName);
Win32API.CloseHandle(ipHandle);
}
}
return null;
}
public static List<Win32API.SYSTEM_HANDLE_INFORMATION>
GetHandles(Process process = null, string IN_strObjectTypeName = null, string IN_strObjectName = null)
{
uint nStatus;
int nHandleInfoSize = 0x10000;
IntPtr ipHandlePointer = Marshal.AllocHGlobal(nHandleInfoSize);
int nLength = 0;
IntPtr ipHandle = IntPtr.Zero;
while ((nStatus = Win32API.NtQuerySystemInformation(CNST_SYSTEM_HANDLE_INFORMATION, ipHandlePointer,
nHandleInfoSize, ref nLength)) ==
STATUS_INFO_LENGTH_MISMATCH)
{
nHandleInfoSize = nLength;
Marshal.FreeHGlobal(ipHandlePointer);
ipHandlePointer = Marshal.AllocHGlobal(nLength);
}
byte[] baTemp = new byte[nLength];
Marshal.Copy(ipHandlePointer, baTemp, 0, nLength);
long lHandleCount = 0;
if (Is64Bits())
{
lHandleCount = Marshal.ReadInt64(ipHandlePointer);
ipHandle = new IntPtr(ipHandlePointer.ToInt64() + 8);
}
else
{
lHandleCount = Marshal.ReadInt32(ipHandlePointer);
ipHandle = new IntPtr(ipHandlePointer.ToInt32() + 4);
}
Win32API.SYSTEM_HANDLE_INFORMATION shHandle;
List<Win32API.SYSTEM_HANDLE_INFORMATION> lstHandles = new List<Win32API.SYSTEM_HANDLE_INFORMATION>();
for (long lIndex = 0; lIndex < lHandleCount; lIndex++)
{
shHandle = new Win32API.SYSTEM_HANDLE_INFORMATION();
if (Is64Bits())
{
shHandle = (Win32API.SYSTEM_HANDLE_INFORMATION)Marshal.PtrToStructure(ipHandle, shHandle.GetType());
ipHandle = new IntPtr(ipHandle.ToInt64() + Marshal.SizeOf(shHandle) + 8);
}
else
{
ipHandle = new IntPtr(ipHandle.ToInt64() + Marshal.SizeOf(shHandle));
shHandle = (Win32API.SYSTEM_HANDLE_INFORMATION)Marshal.PtrToStructure(ipHandle, shHandle.GetType());
}
if (process != null)
{
if (shHandle.ProcessID != process.Id) continue;
}
string strObjectTypeName = "";
if (IN_strObjectTypeName != null){
strObjectTypeName = getObjectTypeName(shHandle, Process.GetProcessById(shHandle.ProcessID));
if (strObjectTypeName != IN_strObjectTypeName) continue;
}
string strObjectName = "";
if (IN_strObjectName != null){
strObjectName = getObjectName(shHandle, Process.GetProcessById(shHandle.ProcessID));
if (strObjectName != IN_strObjectName) continue;
}
string strObjectTypeName2 = getObjectTypeName(shHandle, Process.GetProcessById(shHandle.ProcessID));
string strObjectName2 = getObjectName(shHandle, Process.GetProcessById(shHandle.ProcessID));
Console.WriteLine("{0} {1} {2}", shHandle.ProcessID, strObjectTypeName2, strObjectName2);
lstHandles.Add(shHandle);
}
return lstHandles;
}
public static bool Is64Bits()
{
return Marshal.SizeOf(typeof(IntPtr)) == 8 ? true : false;
}
}
class Program
{
static void Main(string[] args)
{
String MutexName = "MSCTF.Asm.MutexDefault1";
String ProcessName = "notepad";
try
{
Process process = Process.GetProcessesByName(ProcessName)[0];
var handles = Win32Processes.GetHandles(process, "Mutant", "\\Sessions\\1\\BaseNamedObjects\\" + MutexName);
if (handles.Count == 0) throw new System.ArgumentException("NoMutex", "original");
foreach (var handle in handles)
{
IntPtr ipHandle = IntPtr.Zero;
if (!Win32API.DuplicateHandle(Process.GetProcessById(handle.ProcessID).Handle, handle.Handle, Win32API.GetCurrentProcess(), out ipHandle, 0, false, Win32API.DUPLICATE_CLOSE_SOURCE))
Console.WriteLine("DuplicateHandle() failed, error = {0}", Marshal.GetLastWin32Error());
Console.WriteLine("Mutex was killed");
}
}
catch (IndexOutOfRangeException)
{
Console.WriteLine("The process name '{0}' is not currently running", ProcessName);
}
catch (ArgumentException)
{
Console.WriteLine("The Mutex '{0}' was not found in the process '{1}'", MutexName, ProcessName);
}
Console.ReadLine();
}
}
}