rlogind(1M) C2 Trusted DG/UX 5.4.2T rlogind(1M)
NAME
rlogind - remote login server
SYNOPSIS
rlogind [ -d ]
DESCRIPTION
The rlogind server is for the rlogin(1C) program. The server
provides a remote login facility with authentication based on
privileged port numbers. The -d option turns on debugging, with
output going to /tmp/rlogind*.
The rlogind program is invoked by the inetd server when an incoming
connection is detected on the port specified in /etc/services. See
inetd(1M) and services(4) for details. When a service request is
received, inetd invokes rlogind and the following protocol is
initiated:
1) The server checks the client's source port. If the port is
not in the range 0-1023, the server aborts the connection.
2) The server checks the client's source address. If the address
is associated with a host for which no corresponding entry
exists in the hostname database (see hosts(4)), the server
aborts the connection.
After the source port and address have been checked, rlogind
allocates a pseudoterminal (see pty(7)) and manipulates file
descriptors so that the slave half of the pseudoterminal becomes the
stdin, stdout, and stderr for a login process. The login process is
an instance of the login(1) program. The login process may prompt
for a password if the remote user is not a trusted user. On the
Trusted DG/UX System, the login process always prompts for a
password. Furthermore, the user must be specifically authorized for
rlogin service.
The parent of the login process manipulates the master side of the
pseudoterminal, operating as an intermediary between the login
process and the client instance of the rlogin program. In normal
operation, the packet protocol described in pty(7) is invoked to
provide ^S/^Q type facilities and propagate interrupt signals to the
remote programs.
The rlogin command and rlogind server allow for the dynamic exchange
of window size information. This is particularly useful in an
environment in which you use windowing software such as X windows.
Suppose that within a window, you use rlogin to log in to a host. If
you change that window's dimensions through the mouse, the new
dimensions are propagated to the corresponding remote server,
rlogind. The remote kernel data structures are then changed to
reflect these size changes. This information exchange is transparent
to a user. For this enhancement to be fully realized, both the local
and remote machines must be running the appropriate versions of
rlogin and rlogind.
Licensed material--property of copyright holder(s) 1
rlogind(1M) C2 Trusted DG/UX 5.4.2T rlogind(1M)
DIAGNOSTICS
All diagnostic messages are returned on the connection associated
with the stderr, after which any network connections are closed. An
error is indicated by a leading byte with a value of one (1).
Host name for your address (clientIPaddress) unknown
No entry in the hostname database exists for the
client's machine.
Try again A fork by the server failed.
/bin/sh: ... The user's login shell could not be started.
SEE ALSO
rlogin(1C), inetd(1M), ruserok(3X), services(4), hosts(4),
hosts.equiv(4M), inetd.conf(4M), pty(7).
Trusted Facility Manual for the C2 Trusted DG/UX (Trademark) System
(093-701110)
BUGS
The authentication procedure used here assumes the integrity of each
client machine and of the connecting medium. This is not secure but
is useful in an "open" environment. (On the Trusted DG/UX System, no
assumption is made about the integrity of client machines.)
Licensed material--property of copyright holder(s) 2