From: Jonathan Corbet <corbet@stout.atd.ucar.EDU>
Date: Sun, 13 Feb 94 17:41:15 PST
To: cypherpunks@toad.com
Subject: Spread encryption with telnet?
Message-ID: <199402140135.SAA04509@stout.atd.ucar.EDU>
MIME-Version: 1.0
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The current furor over people with password sniffers on the Internet made
me think of another possible option for spreading the use of encryption on
the net.  As everbody knows, the problem is with the passing of plaintext
passwords over the net.  Get rid of these passwords, and the crackers have
to go back to the other 99999 ways of breaking into machines.

It couldn't be very hard to grab a version of telnet and telnetd off the
net and hack in some sort of encryption of the data stream.  Heck, you
could just use the vendor's DES library on systems that have it -- perhaps
not the most aesthetic solution, but easy.  Put in a negotiation option so
that encryption will be used when both ends support it, and you have
instant plug-in relatively secure telnet.

As a bonus, you get your whole session encrypted, not just the password.
It seems like it could be much easier to install than, say, kerberos, and
offer more security.  I would guess that if you made something like this
available and EASY, that lots of people would install it on their machines.
Folks are a little nervous right now, and a sniff-proof telnet might make
them feel better.

If I made a telnet that simply hooked into a vendor's encryption library,
with no internal encryption code, would I have ITAR problems still?  That
may be moot, since any vendor encryption library almost certainly will not
address the problem of coming up with a session key, so probably some sort
of key exchange protocol would have to be put in.

Overall, this seems easy and useful enough that I'm amazed that nobody has
done it yet.  Have I missed something?

jon