community.general/lib/ansible/module_utils/csharp/Ansible.Privilege.cs

444 lines
19 KiB
C#

using Microsoft.Win32.SafeHandles;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.ConstrainedExecution;
using System.Runtime.InteropServices;
using System.Security.Principal;
using System.Text;
namespace Ansible.Privilege
{
internal class NativeHelpers
{
[StructLayout(LayoutKind.Sequential)]
public struct LUID
{
public UInt32 LowPart;
public Int32 HighPart;
}
[StructLayout(LayoutKind.Sequential)]
public struct LUID_AND_ATTRIBUTES
{
public LUID Luid;
public PrivilegeAttributes Attributes;
}
[StructLayout(LayoutKind.Sequential)]
public struct TOKEN_PRIVILEGES
{
public UInt32 PrivilegeCount;
[MarshalAs(UnmanagedType.ByValArray, SizeConst = 1)]
public LUID_AND_ATTRIBUTES[] Privileges;
}
}
internal class NativeMethods
{
[DllImport("advapi32.dll", SetLastError = true)]
public static extern bool AdjustTokenPrivileges(
SafeNativeHandle TokenHandle,
[MarshalAs(UnmanagedType.Bool)] bool DisableAllPrivileges,
SafeMemoryBuffer NewState,
UInt32 BufferLength,
SafeMemoryBuffer PreviousState,
out UInt32 ReturnLength);
[DllImport("kernel32.dll")]
public static extern bool CloseHandle(
IntPtr hObject);
[DllImport("kernel32")]
public static extern SafeWaitHandle GetCurrentProcess();
[DllImport("advapi32.dll", SetLastError = true)]
public static extern bool GetTokenInformation(
SafeNativeHandle TokenHandle,
UInt32 TokenInformationClass,
SafeMemoryBuffer TokenInformation,
UInt32 TokenInformationLength,
out UInt32 ReturnLength);
[DllImport("advapi32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
public static extern bool LookupPrivilegeName(
string lpSystemName,
ref NativeHelpers.LUID lpLuid,
StringBuilder lpName,
ref UInt32 cchName);
[DllImport("advapi32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
public static extern bool LookupPrivilegeValue(
string lpSystemName,
string lpName,
out NativeHelpers.LUID lpLuid);
[DllImport("advapi32.dll", SetLastError = true)]
public static extern bool OpenProcessToken(
SafeHandle ProcessHandle,
TokenAccessLevels DesiredAccess,
out SafeNativeHandle TokenHandle);
}
internal class SafeMemoryBuffer : SafeHandleZeroOrMinusOneIsInvalid
{
public SafeMemoryBuffer() : base(true) { }
public SafeMemoryBuffer(int cb) : base(true)
{
base.SetHandle(Marshal.AllocHGlobal(cb));
}
public SafeMemoryBuffer(IntPtr handle) : base(true)
{
base.SetHandle(handle);
}
[ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
protected override bool ReleaseHandle()
{
Marshal.FreeHGlobal(handle);
return true;
}
}
internal class SafeNativeHandle : SafeHandleZeroOrMinusOneIsInvalid
{
public SafeNativeHandle() : base(true) { }
public SafeNativeHandle(IntPtr handle) : base(true) { this.handle = handle; }
[ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
protected override bool ReleaseHandle()
{
return NativeMethods.CloseHandle(handle);
}
}
public class Win32Exception : System.ComponentModel.Win32Exception
{
private string _msg;
public Win32Exception(string message) : this(Marshal.GetLastWin32Error(), message) { }
public Win32Exception(int errorCode, string message) : base(errorCode)
{
_msg = String.Format("{0} ({1}, Win32ErrorCode {2})", message, base.Message, errorCode);
}
public override string Message { get { return _msg; } }
public static explicit operator Win32Exception(string message) { return new Win32Exception(message); }
}
[Flags]
public enum PrivilegeAttributes : uint
{
Disabled = 0x00000000,
EnabledByDefault = 0x00000001,
Enabled = 0x00000002,
Removed = 0x00000004,
UsedForAccess = 0x80000000,
}
public class PrivilegeEnabler : IDisposable
{
private SafeHandle process;
private Dictionary<string, bool?> previousState;
/// <summary>
/// Temporarily enables the privileges specified and reverts once the class is disposed.
/// </summary>
/// <param name="strict">Whether to fail if any privilege failed to be enabled, if false then this will continue silently</param>
/// <param name="privileges">A list of privileges to enable</param>
public PrivilegeEnabler(bool strict, params string[] privileges)
{
if (privileges.Length > 0)
{
process = PrivilegeUtil.GetCurrentProcess();
Dictionary<string, bool?> newState = new Dictionary<string, bool?>();
for (int i = 0; i < privileges.Length; i++)
newState.Add(privileges[i], true);
try
{
previousState = PrivilegeUtil.SetTokenPrivileges(process, newState, strict);
}
catch (Win32Exception e)
{
throw new Win32Exception(e.NativeErrorCode, String.Format("Failed to enable privilege(s) {0}", String.Join(", ", privileges)));
}
}
}
public void Dispose()
{
// disables any privileges that were enabled by this class
if (previousState != null)
PrivilegeUtil.SetTokenPrivileges(process, previousState);
GC.SuppressFinalize(this);
}
~PrivilegeEnabler() { this.Dispose(); }
}
public class PrivilegeUtil
{
private static readonly UInt32 TOKEN_PRIVILEGES = 3;
/// <summary>
/// Checks if the specific privilege constant is a valid privilege name
/// </summary>
/// <param name="name">The privilege constant (Se*Privilege) is valid</param>
/// <returns>true if valid, else false</returns>
public static bool CheckPrivilegeName(string name)
{
NativeHelpers.LUID luid;
if (!NativeMethods.LookupPrivilegeValue(null, name, out luid))
{
int errCode = Marshal.GetLastWin32Error();
if (errCode != 1313) // ERROR_NO_SUCH_PRIVILEGE
throw new Win32Exception(errCode, String.Format("LookupPrivilegeValue({0}) failed", name));
return false;
}
else
{
return true;
}
}
/// <summary>
/// Disables the privilege specified
/// </summary>
/// <param name="token">The process token to that contains the privilege to disable</param>
/// <param name="privilege">The privilege constant to disable</param>
/// <returns>The previous state that can be passed to SetTokenPrivileges to revert the action</returns>
public static Dictionary<string, bool?> DisablePrivilege(SafeHandle token, string privilege)
{
return SetTokenPrivileges(token, new Dictionary<string, bool?>() { { privilege, false } });
}
/// <summary>
/// Disables all the privileges
/// </summary>
/// <param name="token">The process token to that contains the privilege to disable</param>
/// <returns>The previous state that can be passed to SetTokenPrivileges to revert the action</returns>
public static Dictionary<string, bool?> DisableAllPrivileges(SafeHandle token)
{
return AdjustTokenPrivileges(token, null, false);
}
/// <summary>
/// Enables the privilege specified
/// </summary>
/// <param name="token">The process token to that contains the privilege to enable</param>
/// <param name="privilege">The privilege constant to enable</param>
/// <returns>The previous state that can be passed to SetTokenPrivileges to revert the action</returns>
public static Dictionary<string, bool?> EnablePrivilege(SafeHandle token, string privilege)
{
return SetTokenPrivileges(token, new Dictionary<string, bool?>() { { privilege, true } });
}
/// <summary>
/// Get's the status of all the privileges on the token specified
/// </summary>
/// <param name="token">The process token to get the privilege status on</param>
/// <returns>Dictionary where the key is the privilege constant and the value is the PrivilegeAttributes flags</returns>
public static Dictionary<String, PrivilegeAttributes> GetAllPrivilegeInfo(SafeHandle token)
{
SafeNativeHandle hToken = null;
if (!NativeMethods.OpenProcessToken(token, TokenAccessLevels.Query, out hToken))
throw new Win32Exception("OpenProcessToken() failed");
using (hToken)
{
UInt32 tokenLength = 0;
NativeMethods.GetTokenInformation(hToken, TOKEN_PRIVILEGES, new SafeMemoryBuffer(0), 0, out tokenLength);
NativeHelpers.LUID_AND_ATTRIBUTES[] privileges;
using (SafeMemoryBuffer privilegesPtr = new SafeMemoryBuffer((int)tokenLength))
{
if (!NativeMethods.GetTokenInformation(hToken, TOKEN_PRIVILEGES, privilegesPtr, tokenLength, out tokenLength))
throw new Win32Exception("GetTokenInformation() for TOKEN_PRIVILEGES failed");
NativeHelpers.TOKEN_PRIVILEGES privilegeInfo = (NativeHelpers.TOKEN_PRIVILEGES)Marshal.PtrToStructure(
privilegesPtr.DangerousGetHandle(), typeof(NativeHelpers.TOKEN_PRIVILEGES));
privileges = new NativeHelpers.LUID_AND_ATTRIBUTES[privilegeInfo.PrivilegeCount];
PtrToStructureArray(privileges, IntPtr.Add(privilegesPtr.DangerousGetHandle(), Marshal.SizeOf(privilegeInfo.PrivilegeCount)));
}
return privileges.ToDictionary(p => GetPrivilegeName(p.Luid), p => p.Attributes);
}
}
/// <summary>
/// Get a handle to the current process for use with the methods above
/// </summary>
/// <returns>SafeWaitHandle handle of the current process token</returns>
public static SafeWaitHandle GetCurrentProcess()
{
return NativeMethods.GetCurrentProcess();
}
/// <summary>
/// Removes a privilege from the token. This operation is irreversible
/// </summary>
/// <param name="token">The process token to that contains the privilege to remove</param>
/// <param name="privilege">The privilege constant to remove</param>
public static void RemovePrivilege(SafeHandle token, string privilege)
{
SetTokenPrivileges(token, new Dictionary<string, bool?>() { { privilege, null } });
}
/// <summary>
/// Do a bulk set of multiple privileges
/// </summary>
/// <param name="token">The process token to use when setting the privilege state</param>
/// <param name="state">A dictionary that contains the privileges to set, the key is the constant name and the value can be;
/// true - enable the privilege
/// false - disable the privilege
/// null - remove the privilege (this cannot be reversed)
/// </param>
/// <param name="strict">When true, will fail if one privilege failed to be set, otherwise it will silently continue</param>
/// <returns>The previous state that can be passed to SetTokenPrivileges to revert the action</returns>
public static Dictionary<string, bool?> SetTokenPrivileges(SafeHandle token, IDictionary state, bool strict = true)
{
NativeHelpers.LUID_AND_ATTRIBUTES[] privilegeAttr = new NativeHelpers.LUID_AND_ATTRIBUTES[state.Count];
int i = 0;
foreach (DictionaryEntry entry in state)
{
string key = (string)entry.Key;
NativeHelpers.LUID luid;
if (!NativeMethods.LookupPrivilegeValue(null, key, out luid))
throw new Win32Exception(String.Format("LookupPrivilegeValue({0}) failed", key));
PrivilegeAttributes attributes;
switch ((bool?)entry.Value)
{
case true:
attributes = PrivilegeAttributes.Enabled;
break;
case false:
attributes = PrivilegeAttributes.Disabled;
break;
default:
attributes = PrivilegeAttributes.Removed;
break;
}
privilegeAttr[i].Luid = luid;
privilegeAttr[i].Attributes = attributes;
i++;
}
return AdjustTokenPrivileges(token, privilegeAttr, strict);
}
private static Dictionary<string, bool?> AdjustTokenPrivileges(SafeHandle token, NativeHelpers.LUID_AND_ATTRIBUTES[] newState, bool strict)
{
bool disableAllPrivileges;
SafeMemoryBuffer newStatePtr;
NativeHelpers.LUID_AND_ATTRIBUTES[] oldStatePrivileges;
UInt32 returnLength;
if (newState == null)
{
disableAllPrivileges = true;
newStatePtr = new SafeMemoryBuffer(0);
}
else
{
disableAllPrivileges = false;
// Need to manually marshal the bytes requires for newState as the constant size
// of LUID_AND_ATTRIBUTES is set to 1 and can't be overridden at runtime, TOKEN_PRIVILEGES
// always contains at least 1 entry so we need to calculate the extra size if there are
// nore than 1 LUID_AND_ATTRIBUTES entry
int tokenPrivilegesSize = Marshal.SizeOf(typeof(NativeHelpers.TOKEN_PRIVILEGES));
int luidAttrSize = 0;
if (newState.Length > 1)
luidAttrSize = Marshal.SizeOf(typeof(NativeHelpers.LUID_AND_ATTRIBUTES)) * (newState.Length - 1);
int totalSize = tokenPrivilegesSize + luidAttrSize;
byte[] newStateBytes = new byte[totalSize];
// get the first entry that includes the struct details
NativeHelpers.TOKEN_PRIVILEGES tokenPrivileges = new NativeHelpers.TOKEN_PRIVILEGES()
{
PrivilegeCount = (UInt32)newState.Length,
Privileges = new NativeHelpers.LUID_AND_ATTRIBUTES[1],
};
if (newState.Length > 0)
tokenPrivileges.Privileges[0] = newState[0];
int offset = StructureToBytes(tokenPrivileges, newStateBytes, 0);
// copy the remaining LUID_AND_ATTRIBUTES (if any)
for (int i = 1; i < newState.Length; i++)
offset += StructureToBytes(newState[i], newStateBytes, offset);
// finally create the pointer to the byte array we just created
newStatePtr = new SafeMemoryBuffer(newStateBytes.Length);
Marshal.Copy(newStateBytes, 0, newStatePtr.DangerousGetHandle(), newStateBytes.Length);
}
using (newStatePtr)
{
SafeNativeHandle hToken;
if (!NativeMethods.OpenProcessToken(token, TokenAccessLevels.Query | TokenAccessLevels.AdjustPrivileges, out hToken))
throw new Win32Exception("OpenProcessToken() failed with Query and AdjustPrivileges");
using (hToken)
{
if (!NativeMethods.AdjustTokenPrivileges(hToken, disableAllPrivileges, newStatePtr, 0, new SafeMemoryBuffer(0), out returnLength))
{
int errCode = Marshal.GetLastWin32Error();
if (errCode != 122) // ERROR_INSUFFICIENT_BUFFER
throw new Win32Exception(errCode, "AdjustTokenPrivileges() failed to get old state size");
}
using (SafeMemoryBuffer oldStatePtr = new SafeMemoryBuffer((int)returnLength))
{
bool res = NativeMethods.AdjustTokenPrivileges(hToken, disableAllPrivileges, newStatePtr, returnLength, oldStatePtr, out returnLength);
int errCode = Marshal.GetLastWin32Error();
// even when res == true, ERROR_NOT_ALL_ASSIGNED may be set as the last error code
// fail if we are running with strict, otherwise ignore those privileges
if (!res || ((strict && errCode != 0) || (!strict && !(errCode == 0 || errCode == 0x00000514))))
throw new Win32Exception(errCode, "AdjustTokenPrivileges() failed");
// Marshal the oldStatePtr to the struct
NativeHelpers.TOKEN_PRIVILEGES oldState = (NativeHelpers.TOKEN_PRIVILEGES)Marshal.PtrToStructure(
oldStatePtr.DangerousGetHandle(), typeof(NativeHelpers.TOKEN_PRIVILEGES));
oldStatePrivileges = new NativeHelpers.LUID_AND_ATTRIBUTES[oldState.PrivilegeCount];
PtrToStructureArray(oldStatePrivileges, IntPtr.Add(oldStatePtr.DangerousGetHandle(), Marshal.SizeOf(oldState.PrivilegeCount)));
}
}
}
return oldStatePrivileges.ToDictionary(p => GetPrivilegeName(p.Luid), p => (bool?)p.Attributes.HasFlag(PrivilegeAttributes.Enabled));
}
private static string GetPrivilegeName(NativeHelpers.LUID luid)
{
UInt32 nameLen = 0;
NativeMethods.LookupPrivilegeName(null, ref luid, null, ref nameLen);
StringBuilder name = new StringBuilder((int)(nameLen + 1));
if (!NativeMethods.LookupPrivilegeName(null, ref luid, name, ref nameLen))
throw new Win32Exception("LookupPrivilegeName() failed");
return name.ToString();
}
private static void PtrToStructureArray<T>(T[] array, IntPtr ptr)
{
IntPtr ptrOffset = ptr;
for (int i = 0; i < array.Length; i++, ptrOffset = IntPtr.Add(ptrOffset, Marshal.SizeOf(typeof(T))))
array[i] = (T)Marshal.PtrToStructure(ptrOffset, typeof(T));
}
private static int StructureToBytes<T>(T structure, byte[] array, int offset)
{
int size = Marshal.SizeOf(structure);
using (SafeMemoryBuffer structPtr = new SafeMemoryBuffer(size))
{
Marshal.StructureToPtr(structure, structPtr.DangerousGetHandle(), false);
Marshal.Copy(structPtr.DangerousGetHandle(), array, offset, size);
}
return size;
}
}
}