How to get autofs
Getting the autofs source requires downloading a tarball and will often involve applying bug fix patches and possibly a kernel patch. Whether a kernel patch is needed depends on the age of your system's kernel.
Binary packages are available in most Linux distributions.
The version 4 tar and patches can be found at
http://www.kernel.org/pub/linux/daemons/autofs/v4
The version 5 tar and patches can be found at
http://www.kernel.org/pub/linux/daemons/autofs/v5