What to do about a hurt baby rabbit?

I live out in the country and my cat attacked a baby rabbit. He tore tuffs of his fur and skin off his back, but I'm pretty sure no other damage has been done. He doesn't have any vital organ injuries. But the problem is, now that he has been touch by something/someone other than his mother, we cannot let him back into the wild. So now, I think he is in shock, and I don't know the first thing about rabbits. His eyes are open and he's about four to five inches long. Is there anything specific I need to do first. He won't drink any water, and I'm not sure if he eats solid food yet. Help please????