Merge pull request #169 from SeyZ/develop

xep_0065 plugin (Socks5 Bytestreams)

1 files changed, 359 insertions, 0 deletions

diff --git a/sleekxmpp/plugins/xep_0065/proxy.py b/sleekxmpp/plugins/xep_0065/proxy.py
new file mode 100644
index 00000000..4fdd2ad8
--- /dev/null
+++ b/sleekxmpp/plugins/xep_0065/proxy.py
@@ -0,0 +1,359 @@
+import sys
+import logging
+import struct
+
+from threading import Thread, Event
+from hashlib import sha1
+from select import select
+from uuid import uuid4
+
+import stanza
+
+from sleekxmpp.plugins.base import base_plugin
+from sleekxmpp.xmlstream.handler import Callback
+from sleekxmpp.xmlstream.matcher import StanzaPath
+from sleekxmpp.thirdparty.socks import socksocket, PROXY_TYPE_SOCKS5
+
+# Registers the sleekxmpp logger
+log = logging.getLogger(__name__)
+
+
+class xep_0065(base_plugin):
+    """
+    XEP-0065 Socks5 Bytestreams
+    """
+
+    description = "Socks5 Bytestreams"
+    dependencies = set(['xep_0030', ])
+    xep = '0065'
+    name = 'xep_0065'
+
+    # A dict contains for each SID, the proxy thread currently
+    # running.
+    proxy_threads = {}
+
+    def plugin_init(self):
+        """ Initializes the xep_0065 plugin and all event callbacks.
+        """
+
+        # Shortcuts to access to the xep_0030 plugin.
+        self.disco = self.xmpp['xep_0030']
+
+        # Handler for the streamhost stanza.
+        self.xmpp.registerHandler(
+            Callback('Socks5 Bytestreams',
+                     StanzaPath('iq@type=set/socks/streamhost'),
+                     self._handle_streamhost))
+
+        # Handler for the streamhost-used stanza.
+        self.xmpp.registerHandler(
+            Callback('Socks5 Bytestreams',
+                     StanzaPath('iq@type=result/socks/streamhost-used'),
+                     self._handle_streamhost_used))
+
+    def get_socket(self, sid):
+        """ Returns the socket associated to the SID.
+        """
+
+        proxy = self.proxy_threads.get(sid)
+        if proxy:
+            return proxy.s
+
+    def handshake(self, to, streamer=None):
+        """ Starts the handshake to establish the socks5 bytestreams
+        connection.
+        """
+
+        # Discovers the proxy.
+        self.streamer = streamer or self.discover_proxy()
+
+        # Requester requests network address from the proxy.
+        streamhost = self.get_network_address(self.streamer)
+        self.proxy_host = streamhost['socks']['streamhost']['host']
+        self.proxy_port = streamhost['socks']['streamhost']['port']
+
+        # Generates the SID for this new handshake.
+        sid = uuid4().hex
+
+        # Requester initiates S5B negotation with Target by sending
+        # IQ-set that includes the JabberID and network address of
+        # StreamHost as well as the StreamID (SID) of the proposed
+        # bytestream.
+        iq = self.xmpp.Iq(sto=to, stype='set')
+        iq['socks']['sid'] = sid
+        iq['socks']['streamhost']['jid'] = self.streamer
+        iq['socks']['streamhost']['host'] = self.proxy_host
+        iq['socks']['streamhost']['port'] = self.proxy_port
+
+        # Sends the new IQ.
+        return iq.send()
+
+    def discover_proxy(self):
+        """ Auto-discovers (using XEP 0030) the available bytestream
+        proxy on the XMPP server.
+
+        Returns the JID of the proxy.
+        """
+
+        # Gets all disco items.
+        disco_items = self.disco.get_items(self.xmpp.server)
+
+        for item in disco_items['disco_items']['items']:
+            # For each items, gets the disco info.
+            disco_info = self.disco.get_info(item[0])
+
+            # Gets and verifies if the identity is a bytestream proxy.
+            identities = disco_info['disco_info']['identities']
+            for identity in identities:
+                if identity[0] == 'proxy' and identity[1] == 'bytestreams':
+                    # Returns when the first occurence is found.
+                    return '%s' % disco_info['from']
+
+    def get_network_address(self, streamer):
+        """ Gets the streamhost information of the proxy.
+
+        streamer : The jid of the proxy.
+        """
+
+        iq = self.xmpp.Iq(sto=streamer, stype='get')
+        iq['socks']  # Adds the query eleme to the iq.
+
+        return iq.send()
+
+    def _handle_streamhost(self, iq):
+        """ Handles all streamhost stanzas.
+        """
+
+        # Registers the streamhost info.
+        self.streamer = iq['socks']['streamhost']['jid']
+        self.proxy_host = iq['socks']['streamhost']['host']
+        self.proxy_port = iq['socks']['streamhost']['port']
+
+        # Sets the SID, the requester and the target.
+        sid = iq['socks']['sid']
+        requester = '%s' % iq['from']
+        target = '%s' % self.xmpp.boundjid
+
+        # Next the Target attempts to open a standard TCP socket on
+        # the network address of the Proxy.
+        self.proxy_thread = Proxy(sid, requester, target, self.proxy_host,
+                                  self.proxy_port, self.on_recv)
+        self.proxy_thread.start()
+
+        # Registers the new thread in the proxy_thread dict.
+        self.proxy_threads[sid] = self.proxy_thread
+
+        # Wait until the proxy is connected
+        self.proxy_thread.connected.wait()
+
+        # Replies to the incoming iq with a streamhost-used stanza.
+        res_iq = iq.reply()
+        res_iq['socks']['sid'] = sid
+        res_iq['socks']['streamhost-used']['jid'] = self.streamer
+
+        # Sends the IQ
+        return res_iq.send()
+
+    def _handle_streamhost_used(self, iq):
+        """ Handles all streamhost-used stanzas.
+        """
+
+        # Sets the SID, the requester and the target.
+        sid = iq['socks']['sid']
+        requester = '%s' % self.xmpp.boundjid
+        target  = '%s' % iq['from']
+
+        # The Requester will establish a connection to the SOCKS5
+        # proxy in the same way the Target did.
+        self.proxy_thread = Proxy(sid, requester, target, self.proxy_host,
+                                  self.proxy_port, self.on_recv)
+        self.proxy_thread.start()
+
+        # Registers the new thread in the proxy_thread dict.
+        self.proxy_threads[sid] = self.proxy_thread
+
+        # Wait until the proxy is connected
+        self.proxy_thread.connected.wait()
+
+        # Requester sends IQ-set to StreamHost requesting that
+        # StreamHost activate the bytestream associated with the
+        # StreamID.
+        self.activate(iq['socks']['sid'], target)
+
+    def activate(self, sid, to):
+        """ IQ-set to StreamHost requesting that StreamHost activate
+        the bytestream associated with the StreamID.
+        """
+
+        # Creates the activate IQ.
+        act_iq = self.xmpp.Iq(sto=self.streamer, stype='set')
+        act_iq['socks']['sid'] = sid
+        act_iq['socks']['activate'] = to
+
+        # Send the IQ.
+        act_iq.send()
+
+    def deactivate(self, sid):
+        """ Closes the Proxy thread associated to this SID.
+        """
+
+        proxy = self.proxy_threads.get(sid)
+        if proxy:
+            proxy.s.close()
+            del self.proxy_threads[sid]
+
+    def close(self):
+        """ Closes all Proxy threads.
+        """
+
+        for sid, proxy in self.proxy_threads.items():
+            proxy.s.close()
+            del self.proxy_threads[sid]
+
+    def send(self, sid, data):
+        """ Sends the data over the Proxy socket associated to the
+        SID.
+        """
+
+        proxy = self.proxy_threads.get(sid)
+        if proxy:
+            proxy.s.sendall(data)
+
+    def on_recv(self, sid, data):
+        """ Calls when data is recv from the Proxy socket associated
+        to the SID.
+
+        Triggers a socks_closed event if the socket is closed. The sid
+        is passed to this event.
+
+        Triggers a socks_recv event if there's available data. A dict
+        that contains the sid and the data is passed to this event.
+        """
+
+        proxy = self.proxy_threads.get(sid)
+        if proxy:
+            if not data:
+                self.xmpp.event('socks_closed', sid)
+            else:
+                self.xmpp.event('socks_recv', {'sid': sid, 'data': data})
+
+
+class Proxy(Thread):
+    """ Establishes in a thread a connection between the client and
+    the server-side Socks5 proxy.
+    """
+
+    def __init__(self, sid, requester, target, proxy, proxy_port,
+                 on_recv):
+        """ Initializes the proxy thread.
+
+        sid        : The StreamID. <str>
+        requester  : The JID of the requester. <str>
+        target     : The JID of the target. <str>
+        proxy_host : The hostname or the IP of the proxy. <str>
+        proxy_port : The port of the proxy. <str> or <int>
+        on_recv    : A callback called when data are received from the
+                     socket. <Callable>
+        """
+
+        # Initializes the thread.
+        Thread.__init__(self)
+
+        # Because the xep_0065 plugin uses the proxy_port as string,
+        # the Proxy class accepts the proxy_port argument as a string
+        # or an integer. Here, we force to use the port as an integer.
+        proxy_port = int(proxy_port)
+
+        # Creates a connected event to warn when to proxy is
+        # connected.
+        self.connected = Event()
+
+        # Registers the arguments.
+        self.sid = sid
+        self.requester = requester
+        self.target = target
+        self.proxy = proxy
+        self.proxy_port = proxy_port
+        self.on_recv = on_recv
+
+    def run(self):
+        """ Starts the thread.
+        """
+
+        # Creates the socks5 proxy socket
+        self.s = socksocket()
+        self.s.setproxy(PROXY_TYPE_SOCKS5, self.proxy, port=self.proxy_port)
+
+        # The hostname MUST be SHA1(SID + Requester JID + Target JID)
+        # where the output is hexadecimal-encoded (not binary).
+        digest = sha1()
+        digest.update(self.sid)  # SID
+        digest.update(self.requester)  # Requester JID
+        digest.update(self.target)  # Target JID
+
+        # Computes the digest in hex.
+        dest = '%s' % digest.hexdigest()
+
+        # The port MUST be 0.
+        self.s.connect((dest, 0))
+        log.info('Socket connected.')
+        self.connected.set()
+
+        # Blocks until the socket need to be closed.
+        self.listen()
+
+        # Closes the socket.
+        self.s.close()
+        log.info('Socket closed.')
+
+    def listen(self):
+        """ Listen for data on the socket. When receiving data, call
+        the callback on_recv callable.
+        """
+
+        socket_open = True
+        while socket_open:
+            ins = []
+            try:
+                # Wait any read available data on socket. Timeout
+                # after 5 secs.
+                ins, out, err = select([self.s, ], [], [], 5)
+            except Exception, e:
+                # There's an error with the socket (maybe the socket
+                # has been closed and the file descriptor is bad).
+                log.debug('Socket error: %s' % e)
+                break
+
+            for s in ins:
+                data = self.recv_size(self.s)
+                if not data:
+                    socket_open = False
+
+                self.on_recv(self.sid, data)
+
+    def recv_size(self, the_socket):
+        total_len = 0
+        total_data = []
+        size = sys.maxint
+        size_data = sock_data = ''
+        recv_size = 8192
+
+        while total_len < size:
+            sock_data = the_socket.recv(recv_size)
+            if not sock_data:
+                return ''.join(total_data)
+
+            if not total_data:
+                if len(sock_data) > 4:
+                    size_data += sock_data
+                    size = struct.unpack('>i', size_data[:4])[0]
+                    recv_size = size
+                    if recv_size > 524288:
+                        recv_size = 524288
+                    total_data.append(size_data[4:])
+                else:
+                    size_data += sock_data
+            else:
+                total_data.append(sock_data)
+            total_len = sum([len(i) for i in total_data])
+        return ''.join(total_data)