Im pretty sure we can assume from this chapter that the 4th is his father, since they are comparing who Naruto is more alike, and the two people they are comparing are the 4th and that lady from the other village. And if the Rain village is the same village as the lady with the red hair (his mom)....and Pein's hair is red from what we can tell from that colored chapter cover......Oh dear god...Pein is Naruto's Uncle!