Help! My stray loves to bite and claw me

I have a stray cat living in my garage. With the help of Spay and Save had him fixed and shots. He is about a year old. I call him Hannible. He loves me and talks to me all the time. He knows his name and come out of his box to see me. He like to get very close and rub around my legs and hands. I have petted him several times. He purrs and asks for more. Then out of the blue he'll attack me. Maybe a bite or a claw. What can I do ? I almost run from him when he gets close anymore. Help!!

It's so good of you to take such good care of this stray. He actually sounds more like a semi-tamed feral to me.

Check out this article about cat aggression and let me know if it helps.