Is it okay to use a DSLR in snow? Or do you need to have special protection for it?

I have a Nikon D3100 and I'm planning to bring it to our Korea Trip 2 days from now. Since its winter there, I'm afraid something might happen to my DSLR if I use it without protection.
Is it okay to use it? If not, do you know where I can buy protections for it locally?

PS. Even if it doesn't snow, just really really cold weather.

I have used 35 mm, 6x6 cm and dSLR's in snow for decades.

What you need to be aware of is that the batteries will start to lose their power as they get cold. If you carry a spare battery in your pocket, close to your skin, it will stay warm and when the one in the battery starts to fade, you can switch them. The first battery can then warm up again being close to your body.

I always kept my camera inside my coat unless I was shooting. Mind you, that was all mechanical.

The snow will add more atmospheric extra exposure to your photos so adjust a little lower no. When taking pics.( if you will use manual mode). Any modifications for overexposed pics will be a hassle in PhotoShop tricks ---check the Cokin filter website for the best accessories for your Nikon!

I mostly carry the camera in a padded case, such as a Lowepro TLZ2

(which I recently replaced with a 55 AW after the zipper wore out).

In subzero weather I have several handwarmer packs active to keep the battery from getting too cold. I carry a spare in my pocket. I also have a few clean cotton handkerchiefs to wipe off condensation.

To have dexterity without freezing my fingers I often use two pairs of glove liners with a handwarmer between the layers.

Use a tripod with a user friendly quick release plate.

An accessory that every once in a while becomes helpful is a toothbrush. That can be used if there's a sign with raised or indented letters, and you want to clean off/out the snow to make it readable in the picture.

It doesn't snow from where I'm but it rains a lot. A good person holding an umbrella for you in the rain would do good to the camera. In snow I guess your problem won't be the camera but the battery. All current batteries tend fail at very low temperatures. I can just imagine if I did shoot in the snow I'd be either using something to keep the camera warm and dry or shoot like crazy then run indoors for safety in between spurts.