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32 .\" @(#)rlogind.8 8.1 (Berkeley) 6/4/93
33 .\" $FreeBSD: src/libexec/rlogind/rlogind.8,v 1.13.2.4 2001/08/16 10:44:17 ru Exp $
40 .Nd remote login server
48 program. The server provides a remote login facility
49 with authentication based on privileged port numbers from trusted hosts.
53 .Bl -tag -width indent
55 Set TCP_NODELAY socket option. This improves responsiveness at the expense of
56 some additional network traffic.
58 Ask hostname for verification.
60 Prevent any authentication based on the user's
62 file, unless the user is logging in as the superuser.
64 Disable keep-alive messages.
67 The following options are valid only if Kerberos is in use:
68 .Bl -tag -width indent
70 Enable Kerberos authentication.
76 encryption for all data passed via the rlogin
77 session. This may impact response time
80 utilization, but provides increased security.
84 listens for service requests at the port indicated in
87 service specification; see
89 When a service request is received the following protocol
93 The server checks the client's source port.
94 If the port is not in the range 512-1023, the server
95 aborts the connection.
97 The server checks the client's source address
98 and requests the corresponding host name (see
103 If the hostname cannot be determined,
104 the dot-notation representation of the host address is used.
105 If the hostname is in the same domain as the server (according to
106 the last two components of the domain name),
110 the addresses for the hostname are requested,
111 verifying that the name and address correspond.
112 Normal authentication is bypassed if the address verification fails.
115 Once the source port and address have been checked,
117 proceeds with the authentication process described in
119 It then allocates a pseudo terminal (see
121 and manipulates file descriptors so that the slave
122 half of the pseudo terminal becomes the
128 The login process is an instance of the
130 program, invoked with the
132 option if authentication has succeeded.
133 If automatic authentication fails, the user is
134 prompted to log in as if on a standard terminal line.
136 The parent of the login process manipulates the master side of
137 the pseudo terminal, operating as an intermediary
138 between the login process and the client instance of the
140 program. In normal operation, the packet protocol described
143 is invoked to provide
145 type facilities and propagate
146 interrupt signals to the remote programs. The login process
147 propagates the client terminal's baud rate and terminal type,
148 as found in the environment variable,
152 The screen or window size of the terminal is requested from the client,
153 and window size changes from the client are propagated to the pseudo terminal.
155 Transport-level keepalive messages are enabled unless the
158 The use of keepalive messages allows sessions to be timed out
159 if the client crashes or becomes unreachable.
161 All initial diagnostic messages are indicated
162 by a leading byte with a value of 1,
163 after which any network connections are closed.
164 If there are no errors before
166 is invoked, a null byte is returned as in indication of success.
171 by the server failed.
183 .Bl -tag -width /etc/hostsxxxxxxxx -compact
185 .It Pa /etc/hosts.equiv
186 .It Ev $HOME Ns Pa /.rhosts
187 .It Pa /var/run/nologin
190 The authentication procedure used here assumes the integrity
191 of each client machine and the connecting medium. This is
192 insecure, but is useful in an
196 A facility to allow all data exchanges to be encrypted should be
199 A more extensible protocol should be used.
206 IPv6 support was added by WIDE/KAME project.