4.3BSD-Reno/src/usr.bin/rlogin/rlogin.1

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.\"     @(#)rlogin.1	6.16 (Berkeley) 7/24/90
.\"
.Dd July 24, 1990
.Dt RLOGIN 1
.Os BSD 4.2
.Sh NAME
.Nm rlogin
.Nd remote login
.Sh SYNOPSIS
.Ar rlogin
.Op Fl 8KLdx
.Op Fl e Ar char
.Op Fl k Ar realm
.Op Fl l Ar username
.Ar host
.Sh DESCRIPTION
.Nm Rlogin
starts a terminal session on a remote host
.Ar host  .
.Pp
.Nm Rlogin
first attempts to use the Kerberos authorization mechanism, described below.
If the remote host does not supporting Kerberos the standard Berkeley
.Pa rhosts
authorization mechanism is used.
The options are as follows:
.Tw Fl
.Tp Fl 8
The
.Fl 8
option allows an eight-bit input data path at all times; otherwise
parity bits are stripped except when the remote side's stop and start
characters are other than ^S/^Q.
Eight-bit mode is the default.
.Tp Fl K
The
.Fl K
option turns off all Kerberos authentication.
.Tp Fl L
The
.Fl L
option allows the rlogin session to be run in ``litout'' (see
.Xr tty  4  )
mode.
.Tp Fl d
The
.Fl d
option turns on socket debugging (see
.Xr setsockopt  2  )
on the TCP sockets used for communication with the remote host.
.Tp Fl e
By default, the tilde (``~'') character is the escape character.
The
.Fl e
option allows specification of a different escape character.
.Tp Fl k
The
.FL k
option requests rlogin to obtain tickets for the remote host
in realm
.Ar realm
instead of the remote host's realm as determined by
.Xr krb_realmofhost  3  .
.Tp Fl x
The
.Fl x
option turns on DES encryption for all data passed via the
rlogin session.
This may impact response time and CPU utilization, but provides
increased security.
.Tp
.Pp
A line of the form ``~.'' disconnects from the remote host, where ``~''
is the escape character.
Similarly, the line ``~^Z'' will suspend the
.Nm rlogin
session.
Substitution of the delayed-suspend character (normally ^Y) for the
suspend character suspends the send portion of the rlogin, but allows
output from the remote system.
.Pp
All echoing takes place at the remote site, so that (except for delays)
the
.Nm rlogin
is transparent.
Flow control via ^S/^Q and flushing of input and output on interrupts
are handled properly.
.Sh KERBEROS AUTHENTICATION
Each user may have a private authorization list in the file
.Pa .klogin
in their home directory.
Each line in this file should contain a Kerberos principal name of the
form
.Ar principal.instance@realm  .
If the originating user is authenticated to one of the principals named
in
.Pa .klogin ,
access is granted to the account.
The principal
.Ar accountname.@localrealm
is granted access if
there is no
.Pa .klogin
file.
Otherwise a login and password will be prompted for on the remote machine
as in
.Xr login  1  .
To avoid certain security problems, the
.Pa .klogin
file must be owned by
the remote user.
.Pp
If Kerberos authentication fails, a warning message is printed and the
standard Berkeley
.Em rlogin
is used instead.
.Sh ENVIRONMENT
The following environment variable is utilized by
.Nm rlogin :
.Tw Fl
.Tp Ev TERM
to find user's terminal type.
.Tp
.Sh SEE ALSO
.Xr rsh 1 ,
.Xr kerberos 3 ,
.Xr krb_sendauth 3 ,
.Xr krb_realmofhost 3
.Sh HISTORY
.Nm Rlogin
appeared in 4.2 BSD.
.Sh BUGS
.Nm Rlogin
will be replaced by
.Xr telnet  1
in the near future.
.Pp
More of the environment should be propagated.