What's the best method for supporting implementation-specific object metadata? (while hopefully still being stongly-typed)

In the interests of keeping this short (and on-point), I'm going to lay out three short object constructs and then explain what it is that I'm trying to accomplish here.

tree_object class-

class tree_object
{
protected:
    std::string    name_;
    tree_object*   root_;
    uint32_t       type_;

    // tree_objec::tree_object();
    tree_object(enum OBJECT_TYPE type);

    // tree_objec::tree_object();
    tree_object(std::string name, enum OBJECT_TYPE type = ENTITY);

    // tree_objec::tree_object();
    tree_object(std::string name, enum OBJECT_TYPE type, tree_object& parent)开发者_StackOverflow中文版;

public:
    // default constructor.
    tree_object();

   // Attach me to some parent node.
   virtual bool attach(tree_object& parent);

   // Detach me from my current parent.
   virtual bool detach(bool forced = false);

   // Get object name
   virtual operator std::string();

   // Set object name
   void operator=(std::string value);

   // Get object type
   virtual operator uint32_t();
};

directory_object-

class directory_object: public tree_object
{   
    // List of children
    std::vector<tree_object> children;

public:
    // Attach me to some parent node.
    bool attach(tree_object& parent);

    // Detach me from my current parent.
    bool detach(bool forced = false);

    directory_object(std::string element_name = "");
    directory_object(std::string element_name, tree_object& parent);
    directory_object(std::string element_name, directory_object& parent);
};

filesystem_object-

class filesystem_object: public tree_object
{   
public:
    // Attach me to some parent node.
    bool attach(tree_object& parent);

    // Detach me from my current parent.
    bool detach(bool forced = false);

    filesystem_object(std::string element_name = "");
    filesystem_object(std::string element_name, tree_object& parent);
    filesystem_object(std::string element_name, directory_object& parent);
};

Given the above object definitions, what I'm looking to do is add support for the following concepts to directory_object and filesystem_object:

1. implementation-specific ACL entries for both directory_object and filesystem_object
2. implementation-specific user tag-data (i.e. a struct that means something to the code iterating a specific instance of the tree.)

Given the information above, how best would I be able to accomplish these goals?

P.S. This might be a future implementation detail, but I am eventually going to be accessing my tree implementation "remotely" (i.e. this is going to wind up in a threaded server, so any assistance provided here should be able to be implemented both there and here.)

Thanks.