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+## wsproxy: WebSockets to TCP Proxy
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+
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+
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+### How it works
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+
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+At the most basic level, wsproxy just translates WebSockets traffic
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+to normal socket traffic. wsproxy accepts the WebSockets handshake,
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+parses it, and then begins forwarding traffic between the client and
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+the target in both directions. WebSockets payload data is UTF-8
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+encoded so in order to transport binary data it must use an encoding
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+that can be encapsulated within UTF-8. wsproxy uses base64 to encode
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+all traffic to and from the client. Also, WebSockets traffic starts
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+with '\0' (0) and ends with '\xff' (255). Some buffering is done in
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+case the data from the client is not a full WebSockets frame (i.e.
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+does not end in 255).
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+
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+
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+### Additional features
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+
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+These are not necessary for the basic operation.
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+
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+* Daemonizing: When the `-f` option is not specified, wsproxy runs
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+ in the background as a daemon process.
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+
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+* SSL (the wss:// WebSockets URI): This is detected automatically by
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+ wsproxy by sniffing the first byte sent from the client and then
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+ wrapping the socket if the data starts with '\x16' or '\x80'
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+ (indicating SSL).
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+
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+* Flash security policy: wsproxy detects flash security policy
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+ requests (again by sniffing the first packet) and answers with an
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+ appropriate flash security policy response (and then closes the
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+ port). This means no separate flash security policy server is needed
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+ for supporting the flash WebSockets fallback emulator.
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+
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+* Session recording: This feature that allows recording of the traffic
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+ sent and received from the client to a file using the `--record`
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+ option.
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+
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+
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+### Implementations
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+
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+There are two implementations of wsproxy included: a python
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+implementation and a C implementation.
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+
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+Here is the feature support matrix for the wsproxy implementations:
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+
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+
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+<table>
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+ <tr>
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+ <th>Implementation</th>
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+ <th>Basic Proxying</th>
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+ <th>Daemonizing</th>
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+ <th>SSL/wss</th>
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+ <th>Flash Policy Server</th>
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+ <th>Session Recording</th>
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+ </tr> <tr>
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+ <td>python</td>
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+ <td>yes</td>
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+ <td>yes</td>
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+ <td>yes 1</td>
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+ <td>yes</td>
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+ <td>yes</td>
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+ </tr> <tr>
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+ <td>C</td>
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+ <td>yes</td>
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+ <td>yes</td>
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+ <td>yes</td>
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+ <td>yes</td>
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+ <td>no</td>
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+ </tr>
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+</table>
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+
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+* Note 1: to use SSL/wss with python 2.5 or older, see the following
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+ section on *Building the Python ssl module*.
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+
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+
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+### Building the Python ssl module (for python 2.5 and older)
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+
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+* Install the build dependencies. On Ubuntu use this command:
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+
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+ sudo aptitude install python-dev bluetooth-dev
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+
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+* Download, build the ssl module and symlink to it:
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+
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+ cd noVNC/utils
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+ wget http://pypi.python.org/packages/source/s/ssl/ssl-1.15.tar.gz
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+ tar xvzf ssl-1.15.tar.gz
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+ cd ssl-1.15
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+ make
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+ cd ../
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+ ln -sf ssl-1.15/build/lib.linux-*/ssl ssl
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+
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