NFL needs some rule changes

I think the ball carriers stiff arm to the face is one action that needs a rule change. The defense can't put there hands in the face of the offense. Why has this been allowed just because a player has the ball. It is dangerous as hell and needs to be stopped. Everyone knows the dangers of grabbing the ball carriers face mask. So what's the difference? I say it needs to be enforced both ways and make it a penalty to put your hands in anybody's face mask.