Can I use Canon lenses on a Nikon dSLR?

I believe that is the one you can't do. One of the big two mounts their lenses too far from the sensor to use the other's lens system. I don't recall for sure which it is, but as there is an adapter to use Nikon lenses on an EOS body on B&H, presumably it is the Canon lenses that can't work on a Nikon body.

In cases where an extension tube would work, you will be able to use a lens potentially, but there will be other impacts on things like focus range.

You won't readily find a Canon EOS → Nikon F or Canon FD/FL → Nikon F adapter. There are reasons for this.

• A lens's ability to focus through the entire distance range to infinity relies heavily upon the distance it's held from the image plane. This is known as the register distance or flange focal distance, and it's specific to each mount system. The Nikon F distance is 46.5mm. The Canon EOS distance is 44mm; the Canon FD/FL distance is 42mm. So, it's easy to build a mechanical ring that makes up the 2.5mm between Canon EOS and Nikon so you can mount a Nikon F lens on a Canon EOS dSLR body and use it (albeit without electronic communication; more on this below).
  
  But in the reverse direction, you'd have to shave off 2.5mm from either the lens mount or the camera mount, and you're liable to have the lens's rear element collide with the mirror if you manage to do so. If you do find an adapter ring it must act like a macro extension tube by holding the lens farther away than its registration distance. So an optical element is required to act as a short teleconverter to regain focus to infinity. If the glass is cheap, it's liable to degrade image quality. Without glass, the lens will only be able to focus relatively closely, so for macro or close portrait use, it might be ok, but it's relatively rare to find one of these rings.

• The electronic mount communication between the camera and the lens is proprietary and adapter rings don't translate between the two, so you give up all the features that require camera/lens communication (e.g., camera body control of the lens aperture [i.e., you can only shoot in M or A], wide-open metering, lens EXIF information, autofocus).

• The Nikon D3x00/D40 and D5x00/D60 models cannot perform stop-down metering. So even if you're willing to give up focus to infinity and try and use an adapter ring, you'll lose accurate metering.

• Canon EOS lenses have no aperture rings. Without electronic communication and with no manual way to adjust the aperture, you either have to shoot wide open all the time, or you have to mount the EOS lens on a Canon body, set the aperture, hold down the DOF button and unmount it and then put it on your Nikon body. And go through this little ritual every time you want to change the aperture. FD/FL lenses, however, do have aperture rings.

The only practical way I've seen to adapt other (mostly manual-focus) mount SLR lenses to Nikon F for those of us without machine shops and experience tinkering with lenses and camera bodies, are the Leitax lens mount replacement kits, and the only mounts they provide Nikon kits for are Leica R, Contax/Yashica (think: Zeiss), and Olympus OM lenses.

In short, you'd probably be better off selling your Canon lenses and purchasing Nikon lenses for your D3200. But if you have to use these lenses, then get a Canon EOS dSLR body to match your glass if it's EOS, or get a mirrorless camera body and an adapter if they're Canon FD/FL.

Canon lens to Nikon body infinity focus adapter. Have a look at this: http://camerapix.co.uk/index.php?id_product=293&controller=product

Since the registration distance for the Nikon F-mount is larger than the registration distance for the Canon EF-mount, there is not a simple adapter that will work well, still allow infinity focus, and not change the focal length/maximum f-number through the use of additional optics.

The registration distance is the spacing between the camera's film plane or sensor and the lens mounting flange. It is often referred to as the 'flange focal distance.' The Nikon F-mount has a registration distance of 46.5mm. The Canon EF mount has a registration distance of 44mm.

It's fairly easy to adapt lenses designed with a longer registration distance to a camera with a shorter one. We just need to add a spacer so that the adapted lens sits at its designed distance in front of the camera's mounting flange.

The opposite, though, would require an adapter with negative thickness that would allow the adapted lens to protrude into the throat of the camera. This is physically impossible in the case of Canon EF -mount lenses and Nikon F-mount cameras. The Canon EF-mount has a larger throat diameter than the Nikon F-mount. There's no room to allow an adapter to attach to the front of the Nikon's 44mm diameter mounting flange spaced 46.5mm in front of the sensor and then protrude 2.5mm into the camera to place a larger 54mm diameter mounting flange for the EF lens only 44mm in front of the sensor - the smaller Nikon flange ring is in the way. There would also likely be clearance issues with the reflex mirror for Nikon FF cameras.

The only way to adapt an EF lens to an F-mount body so that it can focus further than just a few inches to a few feet in front of the lens (depending on the particular lens) would be to use an adapter with a mild magnification lens. This is essentially a teleconverter, which comes with optical image quality penalties as well as an increased f-number at maximum aperture. Making one that is fairly affordable would result in a significant loss of image quality. To the best of my knowledge, no such adapter is currently available commercially.