You can start clipping his nails, and keep a spray bottle handy at all times. Just a spray bottle of water, and when he goes into attack mode, "spritz" him. It won't hurt him, but he should get the message that is unwanted behavior. Clipping his nails will help the attacks to your skin do less damage, and getting him used to it this young can only be a good thing!

I am sure he will calm down as he grows up, but these are things you can do right now to curb unwanted behavior.