Run with ghost, cold blooded, engineer, dexterity, riot shield, emps, any primary weapon and put a silencer on it.
The riot shield is so they will shoot that on your back instead of you, giving you the chance to turn around and get them or you can try and use it as a decoy and flank them if they have engineer, ghost to stay off radar while running, cold blooded for the target finder camper, dexterity to gain control of other run and gunners, emps to take out claymores and betties. Silencer on primary weapon to stay off radar and less chance of being heard from players nearby.
enjoy and you can take the riot shield away for two more slots of your choice.
I camp sometimes and the biggest mistake people make is thinking that all campers are bad.
I played a game of CTF the other day against a few people 1 saying he was 120th in the world 2.5k/d etc etc and how we were gonna get smacked, i started on a 15 killstreak, full streaks and he timed out in 3 minutes, and that wasn't camping.
It's going to be hard to kill a good player that is trying to survive.
To beat a good camper you need to be cheap, I can beat any SMG rusher easily with an MK48, it's no challenge.
I'd recommend Ghost, toughness, engineer, dead silence, R870 Shotgun with long barrel, C4, x2 emps.
A good player camper or not will have a headset, dead silence allows you to flank, otherwise I could easily hear someone climbing a ladder or jumping a window.
Ghost allows you to flank, toughness helps 1v1, dead silence allows you to flank safe from headsets and engineer lets you rush straight up to the camper and blast him with the shotgun he will have no warning from his equipment and won't hear you due to dead silence, c4 can help 1v1 and emps can be thrown when you are a distance away to clear equipment and mess with his radar, a camper that uses equipment to protect his back frequently will become much more paranoid when it is destroyed.
Good luck destroying campers, hopefully I'll see you in a game
Here's what I'd put for a class:
SMG or Shotgun with MMS
[Perk 2 Greed]
This class is supposed to help with campers in an enclosed area. Throw an EMP Grenade to get rid of as much of their equipment as possible. Use Flak Jacket and Engineer to get through the rest of their remaining defense. If you can, throw a C4 and send him some RPGs as well. If he's not taken out, then try to get the jump on him by use your MMS to see through the wall and get a bead on him. You should be able to take him out with one shot.
(You can switch out Fast Hands for something else like another attachment and an extra EMP or go for Tactical Mask instead).