Amiga Telnet Daemon --- written by Peter Simons and Steve Holland
Release 2 ()

Copyright
*********

GNU GENERAL PUBLIC LICENSE
Version 2, June 1991

     Copyright (C) 1989, 1991 Free Software Foundation, Inc.
                              675 Mass Ave, Cambridge, MA 02139, USA

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NO WARRANTY
===========

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What is telnetd
***************

telnetd is an abbreviation and stands for ``telnet daemon''. telnetd is a small program that is called by your TCP/IP protocol stack, namely AmiTCP, and handles incoming telnet requests. Thus it enables you to control your Amiga from another machine using a shell or whatever you prefer.

Naturally, telnet is limited to simple I/O and does not feature windows, gadgets or any other graphical user interface stuff. This means, that you can call programs which do operate in the so called terminal modus and do not open their own window for user input and output. Most Internet related tools do so, for example AmigaElm, Arn, Emacs, etc... If you start a program that relies on any mouse interaction, your machine will hang.

For further details you should consult your AmiTCP handbook regarding telnet.

How to install telnetd
**********************

First of all, you'll need to install AmiTCP properly, but that is not described here, I'm afraid. :-) The installation of telnetd is pretty trivial, though: Just copy the telnetd binary included in this distribution archie into AmiTCP:serv. Furthermore, copy the fakesr.device into your DEVS: directory. Then you'll have to edit the config file of your internet daemon, which calls telnetd if a request for a telnet session has been received. This file is called AmiTCP:db/inetd.conf. Go to the last line and insert the following line there:

     telnet    stream tcp nowait root   AmiTCP:serv/telnetd

Finally you'll have to edit your password file, which contains the names of the valid users, their passwords and the shell they should log into. This file is called AmiTCP:db/passwd. Here is an example entry:

     user|passwd|uid|gid|realname|home|shell
     simons|2Ln2ZavvleZxU|1|1|Peter Simons|S:|*NewShell * from s:remote-startup

These entries have the follwing meaning:

user

     This is the name of the user on our machine. This name must be provided when telnetd prompts for ``Login:''.

passwd

     This is the DES-encrypted password of the user, which is required to authenticiate. This password should not be sent manually, but only by the passwd-utility from AmiTCP. If you set the passwd to ``*'' using a text editor, this user will not be prompted for a password but the login is accepted without authenticiation. Usually not a good thing to do... but well, there you have it.

uid
gid
realname

     These entries are not used by telnetd, please consult your manual about their meaning.

home

     Here you can specify the home directory of this user, usually S:. The home directory is set by inetd automatically and all Internet related programs will look there for their configuartion and data files, unless they're configured otherwise. It doesn't have any direct effect for telnetd, though.

shell

     Here you can specify the command that should be issued for this user. Usually this should be a shell. This is done as shown above for the example user simons. The star (``*'') before the ``newshell'' means that telnetd redirects the standard input and output of the called program itself and sends them over the net to the other machine. If you omit the star, the following things will automatically be appended at the end of the command: ``-DEVICE fakesr.device -UNIT 0''. Actually, the number of the UNIT may differ, depending on how many active telnet session your machine has at the moment.

     However, this is useful to call programs which are usually issued by getty of the UUCP package, like AxShell and uucico. Usually, you will want to specify the star operator, though. I never needed the other feature myself and it is quite probably, that it does not work rock solid.

     If you want to have users that are allowd to receive mail and to FTP, but NOT to telnet into your machine, then you may specify ``noshell'' at the shell part and telnetd will refuse their login attempt.

The previously mentioned remote-login script need not necessarily exist, I just use it for minor initialisation, for example:

     Cd RAM:
     alias exit endcli

or

     FailAt 99999
     rexx:rx rexx:uucp2bjoern
     endcli

You may as well omit it and simply call ``*newshell *''.

Known problems
**************

telnetd has been tested here quite a lot and it has worked for me pretty well. There are some known problems, though, especially with the VT emulation. Loging in from an Amiga or UNIX machine usually doesn't make any problems at all, but I have experienced weird stuff when using Windows, MS-DOS or even Napsaterm of AmiTCP. It may have something to do with the fact that telnetd doesn't emulate or interprete a lot but mostly pipes the incoming characters to the shell and vice versa. Actually, I am pretty damn sure that it has something to do with this fact.

However, I don't have the time to fix this rather tricky problem at the moment and since telnetd works after all, you might be able to ignore it. :-) It's nothing serious anyway, it's just that sometimes a newline too much or too little is displayed. That doesn't really hurt IMHO.

Another problem is that telnetd wil hang if you call anything that opens a window and since the Amiga is lacking the resource tracking capabilities of, say, UNIX, I am not able to close that application remotely in case the user who logged in quits usins CTRL-c. so be careful what you start from your shell!

Last but not least, offering a shell over telnetd is totally insecure. The Amiga does not have any multiuser mechanisms and you'll will definitely run into problems if someone hacks your account. Maybe MultiUser.Library is a solution for this, but as far as I know does the current version not work together with AmiTCP 4.2. In case this library is updated any time, telnetd will support it quite nicely as it uses the usergroup.library to determine the data of the user who logged in.

The author
**********

If you want to contact me (e-mail preferred), you may use the following addresses:

SnailMail:
     Peter Simons, Kaiser-Konrad-Straße 80, 53225 Bonn, Germany

Voice:
     +49 228 471397

E-Mail:
     simons@peti.rhein.de

About the author
================

Congratulations! Amongst the 12.42% of software users who actually bother to read the documentation, you are one of the brightest as you have apparently chosen to read the hidden gem in it: The section ``About The Author''.

Disclaimer (What documentation can get along without disclaimer nowadays?): Although this has not been written by Peter Simons himself, it is not necessarily more objectively than it would have been if he did it himself.

As a first approximation to the author, let us have a look at a text he wrote about himself in a list of systems in his home domain. (It may be of interest to some that his self-description has been 4.46 times as long as the actual technical data of his site.)

     I (Peter Simons) was born on Sep 4th 1973 as child of a plain supermodel and a nobel price winner and I had a very nice childhood, although it has always been some kind of nuisance to me that the people used to overlook my really notable IQ because of my extraordinarily handsome appearance.

Note for the reader: I have not known Peter as a child, but you may approximate his look of today by imagining a friendly ice bear with a full beard. (Still a very handsome ice bear, as his ex-girl-friend would probably remark, if she bothered about ``all that computer stuff'' like this text.)

Although Peter is not really a computer freak - telnetd probably owes its existence to the boring breaks between playing and watching basketball, meeting girls, going to parties, watching M*A*S*H, etc. - the adoption of his nickname ``Peti'' as site name for his A3000 homebox (peti.rhein.de) symbolizes the fusion of man and machine to a system of high productivity. Furthermore, the natural environment of Peter is best-suited for computer people: The stationer's shop near his home is the only one I know offering Amigas, Amiga literature and Fish disks just as natural as the more mundane things a stationer sells.

<abrupt and unreasonable break>

This ``About The Author'' section is shareware. If you want to know how it ends or if you have moulded an opinion about Peter Simons utilizing the information provided herein, send me all your money.

Arno Eigenwillig <arno@yaps.dinoco.de>

Acknowledgments
***************

Steve Holland <sdh4@cornell.edu>

     Actually, it is a bit impudent to mention my name at all in this package, because more than 90% of the program is written by Steve. telnetd is mostly based on his package formerly called ``TnServ'', which has been available long before I even thought about looking at TCP/IP. Unfortunately, Steve didn't have the time to support his program any longer and hence, I took the project over.

     All of the protocol stuff, and most of the AmiTCP routines were written by him and all I did was to base my efforts on his code. I may have done some work, though, but lets face it: Until I add a GUI, PGP support and a routine that turns lead into gold, this is still his program.

Michael van Elst
Petra Zeidler

     Both of you have thought me a whole lot about TCP/IP. Petra helped me to install AS225r2, what I was using back then, when I made my first steps with SLIP. Michael has configured my first Ethernet at home and explained me all that stuff with netmasks, broadcasts, etc... it all sounded like black magic to me. What I know about TCP/IP have I learned from you --- and perhaps a bit from Douglas E. Comers book. But really not much.

Bernhard Moellemann

     Thanks for organizing the fabulous computer meeting in Karlsruhe in the last two years. These meetings were always a lot of fun a fantastic opportunity to practise the theoretical knowledge one has about networks. Not to mention the opportunity to learn something completely new and unexpected...

Andreas M. Kirchwitz
Kai `wusel' Siering
Henning Schmiedehausen

     Thanks for the general spirit of inspiration you three bring to USENET. Oh, and for keeping the net clean of course. :-)

Arno Eigenwillig

     This name speaks for itself.  (I bet many of you americans do regret now, that you never paid attention in your German courses!) Thanks Arno, for all those funny phone calls, for testing how much IP traffic my machine can really handle and for forwarding every bloo... uh... interesting news article you see on the net. :-)

Ms. Sylvia Drautzburg

     For giving me so much joy --- and so much trouble in the recent months. She'll probably never read this anyway, but that's what I said about the stuff I wrote for Judith in LharcUUCP's manual, too, and it turned out to be pretty wrong. Anyway Sylvia, have a nice life.

I think I'll better come to an end now, before this manual start to sound like a stupid cracker intro. So many nice people out there.