I have found an instruction for ssh login via mgetty, but it is for
Red Hat Linux, here is the link...

http://etherboot.sourceforge.net/doc/html/sshterminal.html

...and below I'll quote text of that link. I suppose that this can be made
to work on NetBSD (of course?). Can someone tell me how I should do it
differently for NetBSD 1.5.1? I will be wanting to do it over a modem using
mgetty's auto-answer feature. I have had some difficulty getting ppp 
authentication to work without SSH. I also have some questions.

Q1. Will SSH replace the PPP authentication or will it work in addition to 
    PPP authentication?
Q2. After I get it working so that a NetBSD client can call into NetBSD as
    the server, will I be able to get a Win2K client to call into NetBSD as
    the server? [Know that I can now already do this over ethernet. So the
    question is: Will mgetty, used like this, get in the way?]

...Here below begins the text of the instruction for Red Hat Linux. I have
inserted, in brackets, a question or two, like so [Blah blah blah.]...

Serving SSH Sessions
Ken Yap, ken_yap@users.sourceforge.net7 January 1999 

This document shows how to provide a login session that directly connects to 
remote hosts with SSH. 

I wanted a login program that would connect the user directly to a remote 
host with SSH. At first I thought of writing my own login program, then I 
remembered that mgetty could be configured to call any login program. So 
here's what I did: 

In /etc/mgetty+sendfax/login.config I added the line: 

*@*             sshguest        @       /usr/local/etc/mgetty-ssh @

[ This goes in /usr/pkg/etc/mgetty+sendfax/login.config ?]
[ And I can put the script in /usr/pkg/etc/mgetty-ssh.pl ?]

------------------------------

In /etc/inittab I added the line: 

8:35:respawn:/sbin/mgetty -r tty8

I picked a free virtual tty, you may want to expand this to other ttys later. 

[ I can instead put this...
 
  # tty00 is USR external modem with mgetty+sendfax running on it.
  tty00   "/usr/pkg/sbin/mgetty -D -s 115200" dialup     on       insecure
  
  ...in /etc/ttys ? And it won't interfer with normal use of modem for dial   
  out? I can't be two places at once, so I'd never need to do both at once.
]

------------------------------

In /etc/mgetty+sendfax/mgetty.config I added the lines: 

port tty8
toggle-dtr n
ignore-carrier y
blocking y
direct y
login-time -1


------------------------------

I added this user to /etc/passwd: 

sshguest:*:199:199:SSH guest:/tmp:

If you are using shadow passwords you should also add an entry to 
/etc/shadow. 

[ I have no clue about this. Is it the same? ]

------------------------------

The mgetty-ssh Perl script mentioned above is: 

#!/usr/bin/perl
die "No argument\n" if !defined($ARGV[0]);
($name, $host) = split /@/, $ARGV[0];
# remove leading non-alphanums from name and host to prevent
# masquerading as arguments
$name =~ s/^[^a-z0-9]*//;
$host =~ s/^[^a-z0-9]*//;
# remove whitespace as well
$name =~ s/[ \t\f]//g;
$host =~ s/[ \t\f]//g;
# limit length of strings
$name = substr($name, 0, 64);
$host = substr($host, 0, 256);
# do we have anything left?
die "Name or host null\n" if ($name eq '' or $host eq '');
exec '/usr/bin/ssh', '-e', 'none', '-o', 'FallBackToRsh=no',
        '-o', 'StrictHostKeyChecking=yes', '-l', $name, $host;


Make sure this script is executable. If you are concerned that Perl takes up 
too much resources for a transient script, feel free to write the C 
equivalent. 

------------------------------

Make sure any remote hosts you want to connect to have their public keys in 
/etc/ssh/ssh_known_hosts 

[ No problem here, I don't think.]

------------------------------

Now on tty8 enter user@remote as the login name. You will get the following: 

Red Hat Linux release 5.2 (Apollo)
Kernel 2.0.36 on an i486

login: user@remote
user@remote's password:
Last login: Fri Dec 25 10:34:12 1998 from xterm.foo.com.au
No mail.
[user@remote user]$

[ This does not look like a dial-in event. It looks like they just pressed
  CTRL-ALT-F8 or something. Would it be the same when mgetty answers the
  telco line?
]
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