[tbb-dev] Problems with and without tor-launcher

[Mark Smith]

On 3/13/20 12:47 PM, Thomas Klausner wrote:
> I tried enabling it (by moving it in the correct location, with
> tor-browser 9.0.6 and tor-launcher-0.2.20.5) but when I start such a
> tor-browser, I see:
> 
> === Window 1 ===
> Tor Launcher
> 
> Unable to start Tor.
> 
> The Tor executable is missing.
> 
> (OK)
> 
> == Window 2 ====
> 
> Wait for Tor to start...
> 
> For assistance, visit support.torproject.org/#connectingtotor
> 
> (Quit)
> 
> 
> and then it hangs.
> 
> tor is in $PATH, and I have tor already running on that machine, both
> on 9050 and 9150.
> 
> tor-launcher doesn't seem helpful in my use case (packaging for pkgsrc):
> 
> 1. it doesn't find tor even though it's in $PATH
> 2. it doesn't notice a running tor
> 
> Is this something for which I should open bug reports?
> 
> I guess I'll disable it for the package.

Tor Launcher is intended to be used when Tor Browser will start and
control the tor daemon, although it should be possible to have it skip
the "start" task and just handle the "control" task (see below).
Omitting Tor Launcher should be okay too.

> One other thing:  When I start tor-browser with TOR_SKIP_LAUNCH=1, I see
> 
> "Something Went Wrong!"
> Tor is not working in this browser.
> 
> but when I enter an .onion address, it works fine. What's up with that?

There is code inside the Torbutton portion of the browser that (unless
otherwise configured) does a local check to see if the browser is
configured with a SOCKS port that matches the tor configuration. There
are things you can do to have it skip that check and/or to have it
perform a remote check instead; see:
https://gitweb.torproject.org/torbutton.git/tree/chrome/content/torbutton.js?h=maint-9.0#n1224

For example, you can set the TOR_SKIP_CONTROLPORTTEST environment variable.

If you want to keep Tor Launcher as part of the package, you may want to
try using TOR_SKIP_LAUNCH combined with cookie authentication for the
Tor control port. Even if you decide to omit Tor Launcher, there is some
functionality provided by the Torbutton portion of the browser that
requires access to the control port, e.g., new identity. This means that
giving the browser access to the tor control port might be a good thing.

To use cookie authentication with Tor Launcher and/or Torbutton, set the
TOR_CONTROL_COOKIE_AUTH_FILE environment variable to point to the cookie
auth file that is created by your system tor. There are security
considerations to think about though; for more information, see the
CookieAuthentication section within the tor manual. Also, it has been a
while since I tried to make this work, so if you cannot get things
working please open tickets, ask here, or ask on IRC.

Thank you for your work on this and for persevering. The bottom line is
that you can probably get Tor Browser and its components to do what you
want, but the default behavior and the scenarios that we (Tor Browser
developers) develop for are aimed at providing a self-contained bundle
that includes tor. Packaging for a setup that uses a system tor is
something we would like to improve upon but not something we have found
much time to work on.

-- 
Mark Smith
Pearl Crescent, LLC
http://pearlcrescent.com/