[tor-bugs] #8402 [Tor]: Tor should help its transport proxy use a proxy, if needed.

[Tor Bug Tracker & Wiki]

#8402: Tor should help its transport proxy use a proxy, if needed.
-------------------------+-------------------------------------------------
     Reporter:  asn      |      Owner:
         Type:  defect   |     Status:  needs_review
     Priority:  normal   |  Milestone:  Tor: 0.2.6.x-final
    Component:  Tor      |    Version:
   Resolution:           |   Keywords:  tor-bridge pt flashproxy, tbb-
Actual Points:           |  needs, tbb-helpdesk-frequent, tbb-tor-
       Points:           |  backported-3.6.1
                         |  Parent ID:
-------------------------+-------------------------------------------------

Comment (by dcf):

 (As I [[#12120|implement this]] for meek-client...)
 [https://gitweb.torproject.org/torspec.git/blob/abbfc2767d5bbaa81133869ad23926b283c2aed6:/proposals/232
 -pluggable-transports-through-proxy.txt 232-pluggable-transports-through-
 proxy.txt] says:
   If the pluggable transport proxy detects that the TOR_PT_PROXY
 environment variable is set, it attempts connecting to it. On success it
 writes to stdout: "PROXY DONE". On failure it writes: "PROXY-ERROR
 ''<errormessage>''".
 I wonder if it would be better, instead of
 {{{
 PROXY DONE
 }}}
 to emit
 {{{
 PROXY <url>
 }}}
 for example
 {{{
 PROXY socks5://tor:test1234 at 198.51.100.1:8000
 }}}

 The reason for this is that it acts as positive confirmation: "You asked
 me to use a proxy; this is how I understood you."

 Something similar exists with TOR_PT_SERVER_BINDADDR and SMETHOD. Tor can
 ask:
 {{{
 TOR_PT_SERVER_BINDADDR=dummy-127.0.0.1:1111
 }}}
 and the PT can give positive confirmation:
 {{{
 SMETHOD dummy 127.0.0.1:1111
 }}}
 The PT can even disobey tor's requested port, and inform tor that it is
 instead listening on a different port. This is what happens, for example,
 if you use the `--port` option in websocket-server and others.
 {{{
 SMETHOD dummy 127.0.0.1:9999
 }}}

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/8402#comment:29>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online