Most chinese "antiques" are clever replicas...
The characters are 有由浇 I beleive... though it could be 有田浇... but it makes less sense...
It means "poured" or "cast" but I don't know if thats a makers mark or just a descriptive term like we would mark "tin over brass" in english...
The picture of the white flower on the inside is a lotus... very common figure in chinese culture...
I'm not even close to knowledgeable about chinese porcelain... but yours doesn't seem to indicate a lot of age other than the style... there's no visible crackling, no discoloration... so if I had to guess its probably a fairly recent reproduction...