This is the shell_config module. It encapsulates the shell_config type given by Tim Bishop on the Puppet Wiki. CSAIL staff did not write this, and MIT has no copyright claims over it. In fact, we don't even know what the appropriate license is -- presumably whatever contributor license was agreed to by Mr. Bishop when posting to the Puppet Wiki.
The original source is available at: http://projects.puppetlabs.com/projects/1/wiki/Puppet_Free_Bsd