[tor-dev] Special-use-TLD support

[Roger Dingledine]

On Mon, Sep 28, 2015 at 03:20:47PM +0200, Jeff Burdges wrote:
> I proposed that Tor implement NameService rules using UNIX domain
> sockets, or ports, since that's how GNUNet works, but maybe Tor should
> instead launch a helper application it communicates with via stdin and
> stdout.  I donno if that'll work well on Windows however.

If you're to be running a second program that does the "resolves", then
I think you should really think about adding a third program that talks
to Tor on the control port and does all of these rewrites via the control
protocol without needing any further Tor modifications. (If you wanted,
you could make these second and third programs be just one program.)

This is I believe how Jesse's "OnioNS" tool works at present: you connect
to the control port (e.g. via a Stem script), tell Tor that you want to
decide what to do with each new stream (set __LeaveStreamsUnattached to
1), and then you let Tor pick (attachstream to 0) for all the streams
except the special ones. When you see a new special stream, you do the
lookup or resolve or whatever on your side, then REDIRECTSTREAM the
stream to become the new address, then yield control of the stream back
to Tor so Tor picks a circuit for it.

The main downside here is that you need to run a new Tor controller. But
if you're already needing to run a separate program, you should be
all set.

What am I missing?

--Roger