objSize, err = gr.ObjInfo.DecryptedSize()
			if err != nil {
				return nil, ObjectInfo{}, err
			}
		} else {
			objSize = gr.ObjInfo.Size
		}

		files, err := zipindex.ReadDir(b[len(b)-size:], objSize, nil)
		if err == nil {
			return files, gr.ObjInfo, nil
		}
		var terr zipindex.ErrNeedMoreData
		if errors.As(err, &terr) {
			size = int(terr.FromEnd)

	// If so, we try to add it to certificate manager.
	root, err := Open(globalCertsDir.Get())
	if err != nil {
		return nil, nil, false, err
	}
	defer root.Close()

	files, err := root.Readdir(-1)
	if err != nil {
		return nil, nil, false, err
	}
	for _, file := range files {
		// Ignore all
		// - regular files
		// - "CAs" directory
		// - any directory which starts with ".."