Literally speaking, it's not true that PuTTY only connects to the
server you told it to. It typically has to connect to a DNS server
first to find out where that server _is_. (If you've provided a
hostname, and if that hostname isn't in /etc/hosts or equivalent.)
Of course, if you're concerned about people _in your organisation's
network_ finding out where you've been connecting to, you have bigger
problems, because whether you did a DNS lookup or not they can
certainly see your IP-layer headers. But that really is outside the
scope of this document. I only mention DNS out of pedantry, because
not doing so made "does not connect to any other site" technically
inaccurate. (Perhaps even: only inaccurate if the DNS lookup happens
over TCP :-)
Re-reading the wording, I think I was a bit cavalier about "if you
don't like the host key cache recording where you've been, check host
keys yourself." It should be more like "check host keys yourself,
SERIOUSLY, WE REALLY MEAN IT, DO NOT LEAVE THIS STEP OUT."
In the original HTML-only version of the privacy document, there were
two major sections at <h2> level, "stuff stored locally" and "stuff
sent over the network", each with subsections at <h3> level describing
individual aspects. But somehow when I translated it into Halibut to
put it into the manual, they all became \H and the nesting was lost.
Jacob reminds me that that's another piece of saved data, less obvious
than the ones I'd already documented.
I'd actually forgotten myself _exactly_ which actions cause data to be
added to the jump list. But it's easy to check. The only functions
exported from jump-list.c are add_session_to_jumplist(),
remove_session_from_jumplist() and clear_jumplist(); the only one of
those that _records_ information (rather than removing it) is
add_session_to_jumplist(); and that is called in exactly one place,
namely at the end of load_session() in settings.c.
During the 0.81 release process, I found out that the Windows Store
now requires applications to provide a privacy policy, so I had to
write one in order to get 0.81 into the Store.
This initially seemed like makework (especially having to do it in a
hurry as a prerequisite to get a really important security fix
distributed!). But after I started writing it, I found there was
actually quite a lot to say. It's easy to think "PuTTY doesn't phone
home to the developers, that's all, we're done". But of course it
_does_ store information on your machine (host key cache, saved
sessions, etc). And it does send information to servers on the
network (only the ones you ask it to, but even so). And it's not 100%
obvious in every case what is and isn't stored, and what a privacy-
conscious individual might be revealing about themself by doing this
or that thing.
So I think the web page I hastily put up at the time of the 0.81
release deserves to be promoted into part of the documentation. Here's
a (very lightly) copy-edited version in the form of a docs appendix.
(Once this is committed and built, I expect I'll turn the privacy web
page into a mirror of this docs appendix, in the same way as the
website FAQ and feedback pages.)
