Interesting position :)

This position occurred in a chessgame I played 2 days ago(I was white):

White to move



I spent a lot of time analysing this position but I didn't find a winning move so the game ended in a draw...What do you think?

I can't find a win for white either. The best move would be Kd5, and if black moves his rook then white can get his king to d6-c7-d8 and win the rook. If black keeps his rook where it is, i don't think white can do anything.