You don’t need a specific non-squat/non-DL program. Just do any standard BB programming, and don’t include those lifts. My discs are all snapped up, and like another poster said, I thought I could get away with doing contraindicated lifts with light weights. I did that for a long time and paid the price.
I personally find hack squats to be the best replacement for squats. I can do some leg presses, depending on the angle, but I don’t go knees-to-chest deep. Somersault squats have been a great addition; very little stress on the spine. I also find that I can perform smith front squats pain-free (for whatever reason) as long as I just go to parallel and not ATG. Then, of course, you have leg extensions, which I’m not a huge fan of, but are obviously low impact. You also have an array of single-leg movements from which to choose, if you don’t want to completely abandon free weights.
The only DL variation I do is DB RDL’s, holding the DB’s by my sides. My main problem is getting too emotionally worked up, and grabbing the heaviest DB’s in the gym, which inevitably results in a return trip to snap city. But as long as I choose a conservative weight, and focus on using a slow, controlled negative, then I’m GTG. But if the pain is too bad on a given day, I do back extensions instead. And needless to say, you should be doing any variation of hamstring curls in addition.
Instead of BB/DB rows, I do chest-supported versions, or really any other back exercise. No big deal.