telnetlogin should be installed mode 4750, user root, group telnetd. Then, telnetd may be run from /etc/inetd.conf as user ``nobody'', group ``telnetd'', and with the option -L path-to-telnetlogin
telnetlogin accepts only the subset of options to login(1) shown above, in the order listed. This is the order telnetd 8 normally provides them in. telnetlogin also does sanity checks on the environment variables TERM , and REMOTEHOST It also insists that the standard input, output, and error streams are open on a terminal, and that it is the process group leader of the foreground process of that terminal. After checking all of these conditions, checking the values of the above environment variables for reasonable values, resetting signal handlers, and so forth, it execs login.
THIS IS PRESENTLY EXPERIMENTAL CODE; USE WITH CAUTION.