Server for Kerberos-authenticated command execution

 The remctl server (remctld) and SSH backend (remctl-shell), which are
 responsible for receiving an authenticated command via the remctl
 protocol (or via SSH), executing it, and returning the result.
 .
 remctl is a client/server protocol for executing specific commands on a
 remote system with Kerberos authentication. The allowable commands must
 be listed in a server configuration file, and the executable run on the
 server may be mapped to any command name. Each command is also
 associated with an ACL containing a list of Kerberos principals
 authorized to run that command.