Как ssh получил порт 22 и как тогда вообще всё работало. TLDR: в 1995 году порт из диапазона 1-255 можно было зарезервировать за один день одним e-mail'ом "я тут написал клёвую штуку, которая безопасней предыдущих штук, и хочу раздавать её бесплатно, можно мне вот этот порт".
"Anyway, I designed SSH to replace both telnet (port 23) and ftp (port 21). Port 22 was free. It was conveniently between the ports for telnet and ftp. I figured having that port number might be one of those small things that would give some aura of credibility. But how could I get that port number? I had never allocated one, but I knew somebody who had allocated a port.
The basic process for port allocation was fairly simple at that time. Internet was smaller and we were in the very early stages of the Internet boom. Port numbers were allocated by IANA (Internet Assigned Numbers Authority). At the time, that meant an esteemed Internet pioneer called Jon Postel and Joyce K. Reynolds. Among other things, Jon had been the editor of such minor protocol standards as IP (RFC 791), ICMP (RFC 792), and TCP (RFC 793). Some of you may have heard of them.
To me Jon felt outright scary, having authored all the main Internet RFCs!
Anyway, just before announcing ssh-1.0 in July 1995, I sent this e-mail to IANA:
From ylo Mon Jul 10 11:45:48 +0300 1995 From: Tatu Ylonen ylo@cs.hut.fi
To: Internet Assigned Numbers Authority iana@isi.edu
Subject: request for port number
Organization: Helsinki University of Technology, Finland
Dear Sir, I have written a program to securely log from one machine into another over an
insecure network. It provides major improvements in security and functionality over existing
telnet and rlogin protocols and implementations. In particular, it prevents IP, DNS and
outing spoofing. My plan is to distribute the software freely on the Internet and to get it
into as wide use as possible. I would like to get a registered privileged port number for
the software.
The number should preferably be in the range 1-255 so that it can be used in the WKS field
in name servers. I'll enclose the draft RFC for the protocol below. The software has been in
local use for several months, and is ready for publication except for the port number. If
the port number assignment can be arranged in time, I'd like to publish the software already
this week. I am currently using port number 22 in the beta test.
It would be great if this number could be used (it is currently shown as Unassigned in the
lists). The service name for the software is "ssh" (for Secure Shell).
Yours sincerely, Tatu Ylonen ylo@cs.hut.fi ... followed by protocol specification
for ssh-1.0
The next day, I had an e-mail from Joyce waiting in my mailbox:
Date: Mon, 10 Jul 1995 15:35:33 -0700 From: jkrey@ISI.EDU To: ylo@cs.hut.fi Subject:
Re: request for port number Cc: iana@ISI.EDU
Tatu, We have assigned port number 22 to ssh, with you as the point of contact. Joyce