/// <summary>
/// Reset ACL
/// </summary>
public static void SetGracePeriodRegistryKeyPermission(RegistrySecurity rs)
{
Privileges.SetPrivilege("SeTakeOwnershipPrivilege");
Privileges.SetPrivilege("SeBackupPrivilege");
Privileges.SetPrivilege("SeRestorePrivilege");
var key = Registry.LocalMachine.OpenSubKey(TimeBombRegistryKeyName, RegistryKeyPermissionCheck.ReadWriteSubTree, RegistryRights.ChangePermissions | RegistryRights.TakeOwnership);
if (key == null)
{
return; // FIXME: should throw exception here
}
key.SetAccessControl(rs);
key.Close();
}
/// <summary>
/// Bypass ACL by allowing Administrator to write to the key
/// Returns the old ACL
/// </summary>
public static RegistrySecurity SetGracePeriodRegistryKeyPermission()
{
Privileges.SetPrivilege("SeTakeOwnershipPrivilege");
Privileges.SetPrivilege("SeBackupPrivilege");
Privileges.SetPrivilege("SeRestorePrivilege");
var sid = new SecurityIdentifier(WellKnownSidType.BuiltinAdministratorsSid, null);
var account = sid.Translate(typeof(NTAccount)) as NTAccount;
RegistrySecurity oldRs;
// compatibility hell(?)
// https://docs.microsoft.com/en-us/windows/win32/winprog64/registry-redirector?redirectedfrom=MSDN
// https://stackoverflow.com/questions/2464358/why-is-opensubkey-returning-null-on-my-windows-7-64-bit-system/16698274
// var registryLocalMachine = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry64);
var registryLocalMachine = Registry.LocalMachine;
// first, back up old ACL
using (RegistryKey rk = registryLocalMachine.OpenSubKey(TimeBombRegistryKeyName, false))
{
oldRs = rk?.GetAccessControl(AccessControlSections.All);
}
// then get owner
using (RegistryKey rk = registryLocalMachine.OpenSubKey(TimeBombRegistryKeyName, RegistryKeyPermissionCheck.ReadWriteSubTree, RegistryRights.TakeOwnership))
{
RegistrySecurity rs = rk?.GetAccessControl(AccessControlSections.All);
rs?.SetOwner(account ?? throw new InvalidOperationException());
rk?.SetAccessControl(rs ?? throw new InvalidOperationException());
}
using (RegistryKey rk = registryLocalMachine.OpenSubKey(TimeBombRegistryKeyName, RegistryKeyPermissionCheck.ReadWriteSubTree, RegistryRights.ChangePermissions))
{
RegistrySecurity rs = rk?.GetAccessControl(AccessControlSections.All);
Debug.Assert(account != null, nameof(account) + " != null");
RegistryAccessRule rar = new RegistryAccessRule(
account.ToString(),
RegistryRights.FullControl,
InheritanceFlags.ContainerInherit | InheritanceFlags.ObjectInherit,
PropagationFlags.None,
AccessControlType.Allow);
rs?.AddAccessRule(rar);
rk?.SetAccessControl(rs ?? throw new InvalidOperationException());
}
return(oldRs);
}
