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== Quick start for users

You must have a version of Tor that supports pluggable transports. This
means version 0.2.3.2-alpha or later.

All the flashproxy programs and source code can be downloaded this way:
	git clone https://git.torproject.org/flashproxy.git
But as a user you only need these files:
	https://gitweb.torproject.org/flashproxy.git/blob_plain/HEAD:/flashproxy-client
	https://gitweb.torproject.org/flashproxy.git/blob_plain/HEAD:/torrc

You must be able to receive TCP connections; unfortunately means that
you cannot be behind NAT. See the section "Using a public client
transport plugin" below to try out the system even behind NAT.

Run Tor using the included torrc file:
	$ tor -f torrc
By default the transport plugin listens on Internet-facing TCP port
9000. If you have to use a different port (to get through a firewall,
for example), edit the ClientTransportPlugin line of the torrc to give a
different port number:
	ClientTransportPlugin websocket exec ./flashproxy-client --register :0 :8888
If the flashproxy-client program is in a different directoy (after being
installed, for example), use the full path in the ClientTransportPlugin
line:
	ClientTransportPlugin websocket exec /usr/local/bin/flashproxy-client --register

You should receive a flash proxy connection within about 60 seconds. See
"Troubleshooting" below if it doesn't work.


== Overview

This is a set of tools that make it possible to connect Tor through an
browser-based proxy running on another computer. The flash proxy can be
run just by opening a web page in a browser. Flash proxies are one of
several pluggable transports for Tor.

There are five main parts.
1. The Tor client, running on someone's localhost.
2. A client transport plugin, which is a program that waits for
   connections from a flash proxy and connects them to the Tor client.
3. A flash proxy, which is a JavaScript program running in someone's web
   browser.
4. A facilitator, which is a server that keeps a list of clients that
   want a connection and assigns those addresses to proxies.
5. A Tor relay running a server transport plugin capable of receiving
   WebSocket connections.

The purpose of this project is to create many ephemeral bridge IP
addresses, with the goal of outpacing a censor's ability to block them.
Rather than increasing the number of bridges at static addresses, we aim
to make existing bridges reachable by a larger and changing pool of
addresses.


== Demonstration page

This page has a description of the project; viewing it also turns your
computer into a flash proxy as long as the page is open.

http://crypto.stanford.edu/flashproxy/


== Using a public client transport plugin

Rather than running flashproxy-client on your computer, you can use a
public instance of it. This way is not as realistic because all your Tor
traffic will first go to a fixed address and can be easily blocked.
However this is an easy way to try out the system without having to do
port forwarding.
	$ tor ClientTransportPlugin "websocket socks4 fp-facilitator.org:9999" UseBridges 1 Bridge "websocket 0.0.1.0:1" LearnCircuitBuildTimeout 0 CircuitBuildTimeout 60


== Troubleshooting

Make sure someone is viewing http://crypto.stanford.edu/flashproxy/, or
another web page with a flash proxy badge on it.

You can add the --log option to the ClientTransportPlugin command line
in order to save debugging log messages.

If tor hangs at 10% with these messages:
	[notice] Bootstrapped 10%: Finishing handshake with directory server.
	[notice] no known bridge descriptors running yet; stalling
as a last resort you can try deleting the files in ~/.tor and
/var/lib/tor, and then restarting tor.

If tor apparently hangs here:
	[notice] Bootstrapped 50%: Loading relay descriptors.
	[notice] new bridge descriptor '...' (fresh)
wait a few minutes. It can take a while to download relay descriptors.

If you suspect that the facilitator has lost your client registration, you can
re-register:
	$ flashproxy-reg-email
	$ flashproxy-reg-http


== How to run a relay

A server transport plugin for the WebSocket protocol is in the
websocket-transport directory. To build it, you need development tools
for the Go programming language ("apt-get install golang" on Debian).
	$ cd websocket-transport
	$ make
	# make install
You will need a version of Tor supporting the extended OR port protocol.
	$ git clone https://git.torproject.org/user/asn/tor.git -b bug4773_rebase
Add a line like the following to the relay's torrc. You can change the
--port option; make sure that port is open in the firewall.
	ExtORPort 5555
	ServerTransportPlugin websocket exec /usr/local/bin/websocket-server --port 9901


== How to put a flash proxy badge on a web page

Paste in this HTML where you want the badge to appear:

<iframe src="//crypto.stanford.edu/flashproxy/embed.html" width="80" height="15" frameborder="0" scrolling="no"></iframe>