Earlier, Jonathan Corbet wrote:
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.
Overall, this seems easy and useful enough that I'm amazed that nobody has done it yet. Have I missed something?
Although not widely known, a telnet and telnetd combination of this form were constructed by Laurie Brown at ADFA during his development of the LOKI cipher. Draft IETF proposals were also written towards the goal of these extended telnet options and the negotiation procedure becoming a standard. In practice, it worked fine. One drawback was it required DES/LOKI keys to be pregenerated and stored online in an analog of /etc/passwd that the hyper-telnetd would use. The user needed to enter a password on the telnet before the session started, and as for how the negotiation procedures worked, I have absolutely no idea. This was some 2 years ago now and not only are my recollections vague, but at the time I was a 'cryptovirgin' and hence wouldn't know one key exchange from another. As for availability of this software, I don't think it was made a public release (I obtained it from though 'other' channels that I would prefer not to elaborate on -- and it was lost during 'cleansing'). I suggest getting in contact with Laurie Brown at Melbourne University, I believe thats his current abode. I think I will forward him a note, to satisfy my own sense of curiosity. Matthew. footnote: The Australian Defence Force Academy (ADFA) is well known for it's cryptographic school (take a look at AUSCRYPT proceedings). It's a stepping stone to the Defense Signals Directorate (DSD), our analog of the NSA, though not _nearly_ as big (they do share SIGINT info via the UKUSA agreement though). Anyway, since just recently, the DSD is housed a stones throw from ADFA, which makes for interesting liasons. -- Matthew Gream. ph: (02)-821-2043. M.Gream@uts.edu.au. PGPMail and brown paperbags accepted. - Non Servatum -