Whisk together the vinegar, pesto, garlic, salt, and pepper. Gradually add the olive oil, whisking constantly until combined. Set aside or, if using later, pour into a jar.
For the pasta salad:
Add the cooked pasta to a large bowl. Add the tomatoes, cucumber, salami, mozzarella, olives, bell peppers, onion, Parmesan, salt, basil, and parsley.
Whisk (or shake the bottle) the dressing once more, then pour it over the salad, stirring to combine.
Just before serving, sprinkle with more chopped basil, oregano, parsley.