[tor-talk] ScrambleSuit is ready for testing: help needed!

[Philipp Winter]

Over the past months, we have been working on the ScrambleSuit pluggable
transport protocol [1].  The code has now reached some maturity and it's time
to test it!  I set up a dedicated bridge and compiled a set of installation
instructions listed below.  You get bonus points if you test the bridge from
within China since ScrambleSuit should resist the GFW's active probing attacks.

There are probably still some hidden bugs.  If you stumble upon something
unexpected, please file a trac ticket or reply to this email.

So here are the installation instructions.  I tested it on Debian wheezy but it
should work just fine on other Linux distributions.

1. Two additional Python packages are necessary: gmpy and yaml.  Debian has
   them under the names "python-gmpy" and "python-yaml".

2. Clone and compile the current Tor-git (or use a version of your choice as
   long as it is >= v0.2.5.0-alpha-dev):
   $ git clone https://git.torproject.org/tor.git

3. Clone the current version of pyptlib (or use a version of your choice as
   long as it is >= 0.0.5):
   $ git clone https://git.torproject.org/pluggable-transports/pyptlib.git

4. Clone a modified version of obfsproxy which contains the scramblesuit
   branch:
   $ git clone -b scramblesuit https://git.torproject.org/user/phw/obfsproxy.git
   $ cd obfsproxy/
   $ git submodule init
   $ git submodule update

5. You can use the following torrc:
   ------
   DataDirectory /tmp/scramblesuit-torclient
   SOCKSPort auto
   UseBridges 1
   Bridge scramblesuit 193.10.227.195:9002 password=5TYVADJINHBB67PJSBPSWVR5IO742PVO
   ClientTransportPlugin scramblesuit exec <path-to-obfsproxy-dir>/bin/obfsproxy \
      --log-min-severity=debug \
      --log-file=scramblesuit-client.log \
      managed
   ------

6. Now start Tor over ScrambleSuit by executing:
   $ PYTHONPATH=<path-to-obfsproxy-dir>:<path-to-pyptlib-dir> \
   <path-to-tor-dir>/src/or/tor -f <path-to-torrc>

[1] http://www.cs.kau.se/philwint/scramblesuit

Cheers,
Philipp