The sup programs can be built with or without crypting functionality.
If the file  netcryptvoid.c is used no crypting code will be used.
If the file netcrypt.c is used, an engima engine crypting scheme
taken from the BSD 4.3 (1/25/85) file /usr/bin/crypt.c will be used. Since,
this code is both licensed and under U.S. foreign trade restrictions,
we cannot make this code available for anonymous FTP. 

If you want to build a sup client which can encrypt data and you
are a domestic site who has a 4.3 BSD license, we can mail you
a copy of then netcrypt.c file. Just send mail to mach@cs.cmu.edu
requesting the file. 

If you have a crypt.c file available, copy it to the directory
./crypt and the makefile file apply the diff in crypt.diffs to
generate the netcrypt.c file.
