Copyright laws are different in every country, and this list contains links to files in two different collections, so here is a brief summary of some information that may be useful. (victoria.tc.ca)
Second, you can't place app icons, copies of files, or links to files on the desktop. (pcworld.com)
You can provide links to any file or folder, and even prevent people you share with from downloading the file. (lawyerist.com)