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authorLance Stout <lancestout@gmail.com>2011-01-28 00:49:37 -0500
committerLance Stout <lancestout@gmail.com>2011-01-28 00:49:37 -0500
commit1a270dc05cc368000f3545975befa0589031b684 (patch)
tree44eb56db46c08218291a64554ea51e0fa806c3a3
parentbd9bf3f1c7c17606f455ce0cf9c4d0b6b237a7fe (diff)
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First pass at re-worked stream features.
Stream features now use stanza objects! Features are given a ranking that expresses the dependency relationships (since only one feature is negotiated at a time, the dependency graph can be replaced by a line). >>> xmpp.register_feature('my_feature', _my_handler, >>> restart=True, # Requires stream restart >>> order=600) # Ranking (out of ~ 10,000, >>> # lower #'s executed first) SASL mechanisms may now be added or disabled as needed. Each mechanism is given a priority value indicating the order in which the client wishes for mechanisms to be tried. Higher priority numbers are executed first. >>> xmpp.register_sasl_mechanism('SASL-MECH', _mech_handler, >>> priority=0) Disabling a SASL mechanism: >>> xmpp.remove_sasl_mechanism('ANONYMOUS')
-rw-r--r--sleekxmpp/clientxmpp.py361
-rw-r--r--sleekxmpp/stanza/__init__.py3
-rw-r--r--sleekxmpp/stanza/bind.py26
-rw-r--r--sleekxmpp/stanza/sasl.py104
-rw-r--r--sleekxmpp/stanza/session.py25
-rw-r--r--sleekxmpp/stanza/stream_features.py52
-rw-r--r--sleekxmpp/stanza/tls.py50
7 files changed, 473 insertions, 148 deletions
diff --git a/sleekxmpp/clientxmpp.py b/sleekxmpp/clientxmpp.py
index a1813985..e05f8e7b 100644
--- a/sleekxmpp/clientxmpp.py
+++ b/sleekxmpp/clientxmpp.py
@@ -18,9 +18,11 @@ import threading
from sleekxmpp import plugins
from sleekxmpp import stanza
from sleekxmpp.basexmpp import BaseXMPP
-from sleekxmpp.stanza import Message, Presence, Iq
+from sleekxmpp.stanza import *
+from sleekxmpp.stanza import tls
+from sleekxmpp.stanza import sasl
from sleekxmpp.xmlstream import XMLStream, RestartStream
-from sleekxmpp.xmlstream import StanzaBase, ET
+from sleekxmpp.xmlstream import StanzaBase, ET, register_stanza_plugin
from sleekxmpp.xmlstream.matcher import *
from sleekxmpp.xmlstream.handler import *
@@ -92,14 +94,24 @@ class ClientXMPP(BaseXMPP):
self.stream_footer = "</stream:stream>"
self.features = []
- self.registered_features = []
+ self._stream_feature_handlers = {}
+ self._stream_feature_order = []
+ self._sasl_mechanism_handlers = {}
+ self._sasl_mechanism_priorities = []
#TODO: Use stream state here
self.authenticated = False
self.sessionstarted = False
self.bound = False
self.bindfail = False
- self.add_event_handler('connected', self.handle_connected)
+
+ self.add_event_handler('connected', self._handle_connected)
+
+ self.register_stanza(StreamFeatures)
+ self.register_stanza(tls.Proceed)
+ self.register_stanza(sasl.Success)
+ self.register_stanza(sasl.Failure)
+ self.register_stanza(sasl.Auth)
self.register_handler(
Callback('Stream Features',
@@ -112,32 +124,25 @@ class ClientXMPP(BaseXMPP):
'jabber:iq:roster')),
self._handle_roster))
- self.register_feature(
- "<starttls xmlns='urn:ietf:params:xml:ns:xmpp-tls' />",
- self._handle_starttls, True)
- self.register_feature(
- "<mechanisms xmlns='urn:ietf:params:xml:ns:xmpp-sasl' />",
- self._handle_sasl_auth, True)
- self.register_feature(
- "<bind xmlns='urn:ietf:params:xml:ns:xmpp-bind' />",
- self._handle_bind_resource)
- self.register_feature(
- "<session xmlns='urn:ietf:params:xml:ns:xmpp-session' />",
- self._handle_start_session)
-
- def handle_connected(self, event=None):
- #TODO: Use stream state here
- self.authenticated = False
- self.sessionstarted = False
- self.bound = False
- self.bindfail = False
- self.schedule("session timeout checker", 15,
- self._session_timeout_check)
-
- def _session_timeout_check(self):
- if not self.session_started_event.isSet():
- log.debug("Session start has taken more than 15 seconds")
- self.disconnect(reconnect=self.auto_reconnect)
+ self.register_feature('starttls', self._handle_starttls,
+ restart=True,
+ order=0)
+ self.register_feature('mechanisms', self._handle_sasl_auth,
+ restart=True,
+ order=100)
+ self.register_feature('bind', self._handle_bind_resource,
+ restart=False,
+ order=10000)
+ self.register_feature('session', self._handle_start_session,
+ restart=False,
+ order=10001)
+
+ self.register_sasl_mechanism('PLAIN',
+ self._handle_sasl_plain,
+ priority=1)
+ self.register_sasl_mechanism('ANONYMOUS',
+ self._handle_sasl_plain,
+ priority=0)
def connect(self, address=tuple(), reattempt=True):
"""
@@ -197,19 +202,54 @@ class ClientXMPP(BaseXMPP):
return XMLStream.connect(self, address[0], address[1],
use_tls=True, reattempt=reattempt)
- def register_feature(self, mask, pointer, breaker=False):
+ def register_feature(self, name, handler, restart=False, order=5000):
"""
Register a stream feature.
Arguments:
- mask -- An XML string matching the feature's element.
- pointer -- The function to execute if the feature is received.
- breaker -- Indicates if feature processing should halt with
+ name -- The name of the stream feature.
+ handler -- The function to execute if the feature is received.
+ restart -- Indicates if feature processing should halt with
this feature. Defaults to False.
+ order -- The relative ordering in which the feature should
+ be negotiated. Lower values will be attempted
+ earlier when available.
+ """
+ self._stream_feature_handlers[name] = (handler, restart)
+ self._stream_feature_order.append((order, name))
+ self._stream_feature_order.sort()
+
+ def register_sasl_mechanism(self, name, handler, priority=0):
+ """
+ Register a handler for a SASL authentication mechanism.
+
+ Arguments:
+ name -- The name of the mechanism (all caps)
+ handler -- The function that will perform the
+ authentication. The function must
+ return True if it is able to carry
+ out the authentication, False if
+ a required condition is not met.
+ priority -- An integer value indicating the
+ preferred ordering for the mechanism.
+ High values will be attempted first.
+ """
+ self._sasl_mechanism_handlers[name] = handler
+ self._sasl_mechanism_priorities.append((priority, name))
+ self._sasl_mechanism_priorities.sort(reverse=True)
+
+ def remove_sasl_mechanism(self, name):
+ """
+ Remove support for a given SASL authentication mechanism.
+
+ Arguments:
+ name -- The name of the mechanism to remove (all caps)
"""
- self.registered_features.append((MatchXMLMask(mask),
- pointer,
- breaker))
+ if name in self._sasl_mechanism_handlers:
+ del self._sasl_mechanism_handlers[name]
+
+ p = self._sasl_mechanism_priorities
+ self._sasl_mechanism_priorities = [i for i in p if i[1] != name]
def update_roster(self, jid, name=None, subscription=None, groups=[]):
"""
@@ -223,7 +263,8 @@ class ClientXMPP(BaseXMPP):
to 'remove', the entry will be deleted.
groups -- The roster groups that contain this item.
"""
- iq = self.Iq()._set_stanza_values({'type': 'set'})
+ iq = self.Iq()
+ iq['type'] = 'set'
iq['roster']['items'] = {jid: {'name': name,
'subscription': subscription,
'groups': groups}}
@@ -242,10 +283,27 @@ class ClientXMPP(BaseXMPP):
def get_roster(self):
"""Request the roster from the server."""
- iq = self.Iq()._set_stanza_values({'type': 'get'}).enable('roster')
+ iq = self.Iq()
+ iq['type'] = 'get'
+ iq.enable('roster')
response = iq.send()
self._handle_roster(response, request=True)
+ def _handle_connected(self, event=None):
+ #TODO: Use stream state here
+ self.authenticated = False
+ self.sessionstarted = False
+ self.bound = False
+ self.bindfail = False
+ self.features = []
+
+ def session_timeout():
+ if not self.session_started_event.isSet():
+ log.debug("Session start has taken more than 15 seconds")
+ self.disconnect(reconnect=self.auto_reconnect)
+
+ self.schedule("session timeout checker", 15, session_timeout)
+
def _handle_stream_features(self, features):
"""
Process the received stream features.
@@ -253,167 +311,174 @@ class ClientXMPP(BaseXMPP):
Arguments:
features -- The features stanza.
"""
- # Record all of the features.
- self.features = []
- for sub in features.xml:
- self.features.append(sub.tag)
-
- # Process the features.
- for sub in features.xml:
- for feature in self.registered_features:
- mask, handler, halt = feature
- if mask.match(sub):
- if handler(sub) and halt:
- # Don't continue if the feature was
- # marked as a breaker.
- return True
-
- def _handle_starttls(self, xml):
+ for order, name in self._stream_feature_order:
+ if name in features['features']:
+ handler, restart = self._stream_feature_handlers[name]
+ if handler(features) and restart:
+ # Don't continue if the feature requires
+ # restarting the XML stream.
+ return True
+
+ def _handle_starttls(self, features):
"""
Handle notification that the server supports TLS.
Arguments:
- xml -- The STARTLS proceed element.
+ features -- The stream:features element.
"""
- if not self.authenticated and self.ssl_support:
- tls_ns = 'urn:ietf:params:xml:ns:xmpp-tls'
- self.add_handler("<proceed xmlns='%s' />" % tls_ns,
- self._handle_tls_start,
- name='TLS Proceed',
- instream=True)
- self.send_xml(xml)
+
+ def tls_proceed(proceed):
+ """Restart the XML stream when TLS is accepted."""
+ log.debug("Starting TLS")
+ if self.start_tls():
+ self.features.append('starttls')
+ raise RestartStream()
+
+ if self.ssl_support:
+ self.register_handler(
+ Callback('STARTTLS Proceed',
+ MatchXPath(tls.Proceed.tag_name()),
+ tls_proceed,
+ instream=True))
+ self.send(features['starttls'])
return True
else:
log.warning("The module tlslite is required to log in" +\
" to some servers, and has not been found.")
return False
- def _handle_tls_start(self, xml):
+ def _handle_sasl_auth(self, features):
"""
- Handle encrypting the stream using TLS.
+ Handle authenticating using SASL.
- Restarts the stream.
+ Arguments:
+ features -- The stream features stanza.
"""
- log.debug("Starting TLS")
- if self.start_tls():
+
+ def sasl_success(stanza):
+ """SASL authentication succeeded. Restart the stream."""
+ self.authenticated = True
+ self.features.append('mechanisms')
raise RestartStream()
- def _handle_sasl_auth(self, xml):
+ def sasl_fail(stanza):
+ """SASL authentication failed. Disconnect and shutdown."""
+ log.info("Authentication failed.")
+ self.event("failed_auth", direct=True)
+ self.disconnect()
+ log.debug("Starting SASL Auth")
+ return True
+
+ self.register_handler(
+ Callback('SASL Success',
+ MatchXPath(sasl.Success.tag_name()),
+ sasl_success,
+ instream=True,
+ once=True))
+
+ self.register_handler(
+ Callback('SASL Failure',
+ MatchXPath(sasl.Failure.tag_name()),
+ sasl_fail,
+ instream=True,
+ once=True))
+
+ for priority, mech in self._sasl_mechanism_priorities:
+ if mech in self._sasl_mechanism_handlers:
+ handler = self._sasl_mechanism_handlers[mech]
+ if handler(self):
+ break
+ else:
+ log.error("No appropriate login method.")
+ self.disconnect()
+
+ return True
+
+ def _handle_sasl_plain(self, xmpp):
"""
- Handle authenticating using SASL.
+ Attempt to authenticate using SASL PLAIN.
Arguments:
- xml -- The SASL mechanisms stanza.
+ xmpp -- The SleekXMPP connection instance.
"""
- if '{urn:ietf:params:xml:ns:xmpp-tls}starttls' in self.features:
+ if not xmpp.boundjid.user:
return False
- log.debug("Starting SASL Auth")
- sasl_ns = 'urn:ietf:params:xml:ns:xmpp-sasl'
- self.add_handler("<success xmlns='%s' />" % sasl_ns,
- self._handle_auth_success,
- name='SASL Sucess',
- instream=True)
- self.add_handler("<failure xmlns='%s' />" % sasl_ns,
- self._handle_auth_fail,
- name='SASL Failure',
- instream=True)
-
- sasl_mechs = xml.findall('{%s}mechanism' % sasl_ns)
- if sasl_mechs:
- for sasl_mech in sasl_mechs:
- self.features.append("sasl:%s" % sasl_mech.text)
- if 'sasl:PLAIN' in self.features and self.boundjid.user:
- if sys.version_info < (3, 0):
- user = bytes(self.boundjid.user)
- password = bytes(self.password)
- else:
- user = bytes(self.boundjid.user, 'utf-8')
- password = bytes(self.password, 'utf-8')
-
- auth = base64.b64encode(b'\x00' + user + \
- b'\x00' + password).decode('utf-8')
-
- self.send("<auth xmlns='%s' mechanism='PLAIN'>%s</auth>" % (
- sasl_ns,
- auth))
- elif 'sasl:ANONYMOUS' in self.features and not self.boundjid.user:
- self.send("<auth xmlns='%s' mechanism='%s' />" % (
- sasl_ns,
- 'ANONYMOUS'))
- else:
- log.error("No appropriate login method.")
- self.disconnect()
+ if sys.version_info < (3, 0):
+ user = bytes(self.boundjid.user)
+ password = bytes(self.password)
+ else:
+ user = bytes(self.boundjid.user, 'utf-8')
+ password = bytes(self.password, 'utf-8')
+
+ auth = base64.b64encode(b'\x00' + user + \
+ b'\x00' + password).decode('utf-8')
+
+ resp = sasl.Auth(xmpp)
+ resp['mechanism'] = 'PLAIN'
+ resp['value'] = auth
+ resp.send()
+
return True
- def _handle_auth_success(self, xml):
+ def _handle_sasl_anonymous(self, xmpp):
"""
- SASL authentication succeeded. Restart the stream.
+ Attempt to authenticate using SASL ANONYMOUS.
Arguments:
- xml -- The SASL authentication success element.
+ xmpp -- The SleekXMPP connection instance.
"""
- self.authenticated = True
- self.features = []
- raise RestartStream()
+ if xmpp.boundjid.user:
+ return False
- def _handle_auth_fail(self, xml):
- """
- SASL authentication failed. Disconnect and shutdown.
+ resp = sasl.Auth(xmpp)
+ resp['mechanism'] = 'ANONYMOUS'
+ resp.send()
- Arguments:
- xml -- The SASL authentication failure element.
- """
- log.info("Authentication failed.")
- self.event("failed_auth", direct=True)
- self.disconnect()
+ return True
- def _handle_bind_resource(self, xml):
+ def _handle_bind_resource(self, features):
"""
Handle requesting a specific resource.
Arguments:
- xml -- The bind feature element.
+ features -- The stream features stanza.
"""
log.debug("Requesting resource: %s" % self.boundjid.resource)
- xml.clear()
- iq = self.Iq(stype='set')
+ iq = self.Iq()
+ iq['type'] = 'set'
+ iq.enable('bind')
if self.boundjid.resource:
- res = ET.Element('resource')
- res.text = self.boundjid.resource
- xml.append(res)
- iq.append(xml)
+ iq['bind']['resource'] = self.boundjid.resource
response = iq.send()
- bind_ns = 'urn:ietf:params:xml:ns:xmpp-bind'
- self.set_jid(response.xml.find('{%s}bind/{%s}jid' % (bind_ns,
- bind_ns)).text)
+ self.set_jid(response['bind']['jid'])
self.bound = True
+
log.info("Node set to: %s" % self.boundjid.full)
- session_ns = 'urn:ietf:params:xml:ns:xmpp-session'
- if "{%s}session" % session_ns not in self.features or self.bindfail:
+
+ if 'session' not in features['features']:
log.debug("Established Session")
self.sessionstarted = True
self.session_started_event.set()
self.event("session_start")
- def _handle_start_session(self, xml):
+ def _handle_start_session(self, features):
"""
Handle the start of the session.
Arguments:
- xml -- The session feature element.
+ feature -- The stream features element.
"""
- if self.authenticated and self.bound:
- iq = self.makeIqSet(xml)
- response = iq.send()
- log.debug("Established Session")
- self.sessionstarted = True
- self.session_started_event.set()
- self.event("session_start")
- else:
- # Bind probably hasn't happened yet.
- self.bindfail = True
+ iq = self.Iq()
+ iq['type'] = 'set'
+ iq.enable('session')
+ response = iq.send()
+
+ log.debug("Established Session")
+ self.sessionstarted = True
+ self.session_started_event.set()
+ self.event("session_start")
def _handle_roster(self, iq, request=False):
"""
diff --git a/sleekxmpp/stanza/__init__.py b/sleekxmpp/stanza/__init__.py
index dbf7b86f..ef44dfb2 100644
--- a/sleekxmpp/stanza/__init__.py
+++ b/sleekxmpp/stanza/__init__.py
@@ -12,3 +12,6 @@ from sleekxmpp.stanza.stream_error import StreamError
from sleekxmpp.stanza.iq import Iq
from sleekxmpp.stanza.message import Message
from sleekxmpp.stanza.presence import Presence
+from sleekxmpp.stanza.stream_features import StreamFeatures
+from sleekxmpp.stanza.bind import Bind
+
diff --git a/sleekxmpp/stanza/bind.py b/sleekxmpp/stanza/bind.py
new file mode 100644
index 00000000..ae1f96f0
--- /dev/null
+++ b/sleekxmpp/stanza/bind.py
@@ -0,0 +1,26 @@
+"""
+ SleekXMPP: The Sleek XMPP Library
+ Copyright (C) 2010 Nathanael C. Fritz
+ This file is part of SleekXMPP.
+
+ See the file LICENSE for copying permission.
+"""
+
+from sleekxmpp.stanza import Iq, StreamFeatures
+from sleekxmpp.xmlstream import ElementBase, ET, register_stanza_plugin
+
+
+class Bind(ElementBase):
+
+ """
+ """
+
+ name = 'bind'
+ namespace = 'urn:ietf:params:xml:ns:xmpp-bind'
+ interfaces = set(('resource', 'jid'))
+ sub_interfaces = interfaces
+ plugin_attrib = 'bind'
+
+
+register_stanza_plugin(Iq, Bind)
+register_stanza_plugin(StreamFeatures, Bind)
diff --git a/sleekxmpp/stanza/sasl.py b/sleekxmpp/stanza/sasl.py
new file mode 100644
index 00000000..e55a72ad
--- /dev/null
+++ b/sleekxmpp/stanza/sasl.py
@@ -0,0 +1,104 @@
+"""
+ SleekXMPP: The Sleek XMPP Library
+ Copyright (C) 2010 Nathanael C. Fritz
+ This file is part of SleekXMPP.
+
+ See the file LICENSE for copying permission.
+"""
+
+from sleekxmpp.stanza import StreamFeatures
+from sleekxmpp.xmlstream import ElementBase, StanzaBase, ET
+from sleekxmpp.xmlstream import register_stanza_plugin
+
+
+class Mechanisms(ElementBase):
+
+ """
+ """
+
+ name = 'mechanisms'
+ namespace = 'urn:ietf:params:xml:ns:xmpp-sasl'
+ interfaces = set(('mechanisms', 'required'))
+ plugin_attrib = name
+ is_extension = True
+
+ def get_required(self):
+ """
+ """
+ return True
+
+ def get_mechanisms(self):
+ """
+ """
+ results = []
+ mechs = self.findall('{%s}mechanism' % self.namespace)
+ if mechs:
+ for mech in mechs:
+ results.append(mech.text)
+ return results
+
+ def set_mechanisms(self, values):
+ """
+ """
+ self.del_mechanisms()
+ for val in values:
+ mech = ET.Element('{%s}mechanism' % self.namespace)
+ mech.text = val
+ self.append(mech)
+
+ def del_mechanisms(self):
+ """
+ """
+ mechs = self.findall('{%s}mechanism' % self.namespace)
+ if mechs:
+ for mech in mechs:
+ self.xml.remove(mech)
+
+
+class Success(StanzaBase):
+
+ """
+ """
+
+ name = 'success'
+ namespace = 'urn:ietf:params:xml:ns:xmpp-sasl'
+ interfaces = set()
+ plugin_attrib = name
+
+
+class Failure(StanzaBase):
+
+ """
+ """
+
+ name = 'failure'
+ namespace = 'urn:ietf:params:xml:ns:xmpp-sasl'
+ interfaces = set()
+ plugin_attrib = name
+
+
+class Auth(StanzaBase):
+
+ """
+ """
+
+ name = 'auth'
+ namespace = 'urn:ietf:params:xml:ns:xmpp-sasl'
+ interfaces = set(('mechanism', 'value'))
+ plugin_attrib = name
+
+ def setup(self, xml):
+ StanzaBase.setup(self, xml)
+ self.xml.tag = self.tag_name()
+
+ def set_value(self, value):
+ self.xml.text = value
+
+ def get_value(self):
+ return self.xml.text
+
+ def del_value(self):
+ self.xml.text = ''
+
+
+register_stanza_plugin(StreamFeatures, Mechanisms)
diff --git a/sleekxmpp/stanza/session.py b/sleekxmpp/stanza/session.py
new file mode 100644
index 00000000..b7b175d2
--- /dev/null
+++ b/sleekxmpp/stanza/session.py
@@ -0,0 +1,25 @@
+"""
+ SleekXMPP: The Sleek XMPP Library
+ Copyright (C) 2010 Nathanael C. Fritz
+ This file is part of SleekXMPP.
+
+ See the file LICENSE for copying permission.
+"""
+
+from sleekxmpp.stanza import Iq, StreamFeatures
+from sleekxmpp.xmlstream import ElementBase, ET, register_stanza_plugin
+
+
+class Session(ElementBase):
+
+ """
+ """
+
+ name = 'bind'
+ namespace = 'urn:ietf:params:xml:ns:xmpp-session'
+ interfaces = set()
+ plugin_attrib = 'session'
+
+
+register_stanza_plugin(Iq, Session)
+register_stanza_plugin(StreamFeatures, Session)
diff --git a/sleekxmpp/stanza/stream_features.py b/sleekxmpp/stanza/stream_features.py
new file mode 100644
index 00000000..5be2e55f
--- /dev/null
+++ b/sleekxmpp/stanza/stream_features.py
@@ -0,0 +1,52 @@
+"""
+ SleekXMPP: The Sleek XMPP Library
+ Copyright (C) 2010 Nathanael C. Fritz
+ This file is part of SleekXMPP.
+
+ See the file LICENSE for copying permission.
+"""
+
+from sleekxmpp.xmlstream import ElementBase, StanzaBase, ET
+from sleekxmpp.xmlstream import register_stanza_plugin
+
+
+class StreamFeatures(StanzaBase):
+
+ """
+ """
+
+ name = 'features'
+ namespace = 'http://etherx.jabber.org/streams'
+ interfaces = set(('features', 'required', 'optional'))
+ sub_interfaces = interfaces
+
+ def setup(self, xml):
+ StanzaBase.setup(self, xml)
+ self.values = self.values
+
+ def get_features(self):
+ """
+ """
+ return self.plugins
+
+ def set_features(self, value):
+ """
+ """
+ pass
+
+ def del_features(self):
+ """
+ """
+ pass
+
+ def get_required(self):
+ """
+ """
+ features = self['features']
+ return [f for n, f in features.items() if f['required']]
+
+ def get_optional(self):
+ """
+ """
+ features = self['features']
+ return [f for n, f in features.items() if not f['required']]
diff --git a/sleekxmpp/stanza/tls.py b/sleekxmpp/stanza/tls.py
new file mode 100644
index 00000000..d85f9b49
--- /dev/null
+++ b/sleekxmpp/stanza/tls.py
@@ -0,0 +1,50 @@
+"""
+ SleekXMPP: The Sleek XMPP Library
+ Copyright (C) 2010 Nathanael C. Fritz
+ This file is part of SleekXMPP.
+
+ See the file LICENSE for copying permission.
+"""
+
+from sleekxmpp.stanza import StreamFeatures
+from sleekxmpp.xmlstream import StanzaBase, ElementBase
+from sleekxmpp.xmlstream import register_stanza_plugin
+
+
+class STARTTLS(ElementBase):
+
+ """
+ """
+
+ name = 'starttls'
+ namespace = 'urn:ietf:params:xml:ns:xmpp-tls'
+ interfaces = set(('required',))
+ plugin_attrib = name
+
+ def get_required(self):
+ """
+ """
+ return True
+
+
+class Proceed(StanzaBase):
+
+ """
+ """
+
+ name = 'proceed'
+ namespace = 'urn:ietf:params:xml:ns:xmpp-tls'
+ interfaces = set()
+
+
+class Failure(StanzaBase):
+
+ """
+ """
+
+ name = 'failure'
+ namespace = 'urn:ietf:params:xml:ns:xmpp-tls'
+ interfaces = set()
+
+
+register_stanza_plugin(StreamFeatures, STARTTLS)