Wer hat welche Berechtigungen in einem Verzeichnis

[NicoDE]

Zitat von Sharky:

der Hintergrund ist der:

[snip]

Versuch's damit (funktioniert auch mit Verzeichnissen)

Delphi-Quellcode:

(** )
// stuff Delphi might not know...
const
  FILE_READ_DATA            = $0001;  // file & pipe
  FILE_LIST_DIRECTORY       = $0001;  // directory
  FILE_WRITE_DATA           = $0002;  // file & pipe
  FILE_ADD_FILE             = $0002;  // directory
  FILE_APPEND_DATA          = $0004;  // file
  FILE_ADD_SUBDIRECTORY     = $0004;  // directory
  FILE_CREATE_PIPE_INSTANCE = $0004;  // named pipe
  FILE_READ_EA              = $0008;  // file & directory
  FILE_WRITE_EA             = $0010;  // file & directory
  FILE_EXECUTE              = $0020;  // file
  FILE_TRAVERSE             = $0020;  // directory
  FILE_DELETE_CHILD         = $0040;  // directory
  FILE_READ_ATTRIBUTES      = $0080;  // all
  FILE_WRITE_ATTRIBUTES     = $0100;  // all
  FILE_ALL_ACCESS      = STANDARD_RIGHTS_REQUIRED or SYNCHRONIZE or $1FF;
  FILE_GENERIC_READ    = STANDARD_RIGHTS_READ or
                         FILE_READ_DATA or
                         FILE_READ_ATTRIBUTES or
                         FILE_READ_EA or
                         SYNCHRONIZE;
  FILE_GENERIC_WRITE   = STANDARD_RIGHTS_WRITE or
                         FILE_WRITE_DATA or
                         FILE_WRITE_ATTRIBUTES or
                         FILE_WRITE_EA or
                         FILE_APPEND_DATA or
                         SYNCHRONIZE;
  FILE_GENERIC_EXECUTE = STANDARD_RIGHTS_EXECUTE or
                         FILE_READ_ATTRIBUTES or
                         FILE_EXECUTE or
                         SYNCHRONIZE;
(**)

function CheckAccessToFile(DesiredAccess: DWORD; const FileName: WideString): Boolean;
const
  GenericFileMapping: TGenericMapping = (
    GenericRead   : FILE_GENERIC_READ;
    GenericWrite  : FILE_GENERIC_WRITE;
    GenericExecute: FILE_GENERIC_EXECUTE;
    GenericAll    : FILE_ALL_ACCESS
  );
var
  LastError: DWORD;
  LengthNeeded: DWORD;
  SecurityDescriptor: PSecurityDescriptor;
  ClientToken: THandle;
  AccessMask: DWORD;
  PrivilegeSet: TPrivilegeSet;
  PrivilegeSetLength: DWORD;
  GrantedAccess: DWORD;
  AccessStatus: BOOL;
begin
  Result := False;
  LastError := GetLastError;
  if not GetFileSecurityW(PWideChar(FileName), OWNER_SECURITY_INFORMATION or
    GROUP_SECURITY_INFORMATION or DACL_SECURITY_INFORMATION, nil, 0,
    LengthNeeded) and (GetLastError <> ERROR_INSUFFICIENT_BUFFER) then
    Exit;
  SetLastError(LastError);
  Inc(LengthNeeded, $1000);
  SecurityDescriptor := PSecurityDescriptor(LocalAlloc(LPTR, LengthNeeded));
  if not Assigned(SecurityDescriptor) then
    Exit;
  try
    if not GetFileSecurityW(PWideChar(FileName), OWNER_SECURITY_INFORMATION or
      GROUP_SECURITY_INFORMATION or DACL_SECURITY_INFORMATION,
      SecurityDescriptor, LengthNeeded, LengthNeeded) then
      Exit;
    if not ImpersonateSelf(SecurityImpersonation) then
      Exit;
    try
      if not OpenThreadToken(GetCurrentThread, TOKEN_QUERY or
        TOKEN_IMPERSONATE or TOKEN_DUPLICATE, False, ClientToken) then
        Exit;
      try
        AccessMask := DesiredAccess;
        MapGenericMask(AccessMask, GenericFileMapping);
        PrivilegeSetLength := SizeOf(TPrivilegeSet);
        if AccessCheck(SecurityDescriptor, ClientToken, AccessMask,
          GenericFileMapping, PrivilegeSet, PrivilegeSetLength, GrantedAccess,
          AccessStatus) then
          Result := AccessStatus;
      finally
        CloseHandle(ClientToken);
      end;
    finally
      RevertToSelf;
    end;
  finally
    LocalFree(HLOCAL(SecurityDescriptor));
  end;
end;

////////////////////////////////////////////////////////////////////////////////
// Test

procedure TForm1.Button1Click(Sender: TObject);
begin
  if OpenDialog1.Execute then
    ShowMessage(BoolToStr(
      CheckAccessToFile(GENERIC_WRITE,  // check for generic write access
      OpenDialog1.FileName), True) + ': ' + SysErrorMessage(GetLastError));
end;

edit: nicht mein Tag heute *g*