Your son is obviously, unsettled in his life i.e., he may be having substance abuse
problems, or things are going poorly with a girlfriend; he may not be happy at school. The way lots of kids deal with these situations is to externalize blame onto parents, and others around them. This helps them escape responsibility for their own behavior (everyone else is hassling them or irritates them with questions, indirect expectations etc.) The anger and hostility are ways for him to create a wall between you because he really doesn't want you to know that things are bad (he is embarrassed), and he acts 'as if' others are responsible for his problems. So this anger stuff and emotional distance is his best way of coping----it almost certainly has nothing to do with you, how you have treated him, anything you've done wrong, etc. You haven't done anything 'wrong'. But you are simply on the receiving end of his dysfunctional coping behaviors right now.
You should continue to contact him as you normally would, continue to show interest, and not complain or object to abbreviated phone calls. You should call him on his rudeness however. He can be cold and aloof, but tell him that certain remarks or criticisms are "unkind and uncalled for". when they occur. Then, drop it and move on to the next topic of conversation. Your son is immature emotionally and hasn't learned mature, adult ways of coping with emotional hardship, disappointment etc. If he complains about problems, tell him to perhaps talk to someone at the university counseling center---it is free. Tell him, "Maybe it would help to bounce your thoughts and ideas off someone who doesn't know you at all and who can be honest and objective, and still give you complete confidentiality in what you tell them". Right now, just being consistent with him is all-important. Don't take things personally---it isn't about you, it is about his emotional immaturity and lack of coping skills for dealing with stress
, disappointment, frustration. He will likely improve somewhat as he gets older and has more life-learning opportunities. But he will 'revert' back to old coping approaches when he is under considerable stress, is feeling quite depressed, etc.
I hope this information is helpful to you. Please let me know if I have overlooked any aspect of your original question. Please click on the green Accept button at the bottom of the screen. Thanks.