Mercurial > libervia-backend
view sat/plugins/plugin_xep_0198.py @ 3981:acc9dfc8ba8d
component AP gateway: parse body immediately on `POST` request:
the body is parsed immediately during a `POST` request: this avoids duplication of code,
and allows to check the body data before continuing (will be used to filter some requests
in a future patch).
author | Goffi <goffi@goffi.org> |
---|---|
date | Tue, 15 Nov 2022 18:07:34 +0100 |
parents | 888109774673 |
children | 32d714a8ea51 |
line wrap: on
line source
#!/usr/bin/env python3 # SàT plugin for managing Stream-Management # Copyright (C) 2009-2021 Jérôme Poisson (goffi@goffi.org) # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU Affero General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU Affero General Public License for more details. # You should have received a copy of the GNU Affero General Public License # along with this program. If not, see <http://www.gnu.org/licenses/>. from sat.core.i18n import _ from sat.core.constants import Const as C from sat.core import exceptions from sat.core.log import getLogger from twisted.words.protocols.jabber import client as jabber_client from twisted.words.protocols.jabber import xmlstream from twisted.words.xish import domish from twisted.internet import defer from twisted.internet import task, reactor from functools import partial from wokkel import disco, iwokkel from zope.interface import implementer import collections import time log = getLogger(__name__) PLUGIN_INFO = { C.PI_NAME: "Stream Management", C.PI_IMPORT_NAME: "XEP-0198", C.PI_TYPE: "XEP", C.PI_MODES: C.PLUG_MODE_BOTH, C.PI_PROTOCOLS: ["XEP-0198"], C.PI_DEPENDENCIES: [], C.PI_RECOMMENDATIONS: ["XEP-0045", "XEP-0313"], C.PI_MAIN: "XEP_0198", C.PI_HANDLER: "yes", C.PI_DESCRIPTION: _("""Implementation of Stream Management"""), } NS_SM = "urn:xmpp:sm:3" SM_ENABLED = '/enabled[@xmlns="' + NS_SM + '"]' SM_RESUMED = '/resumed[@xmlns="' + NS_SM + '"]' SM_FAILED = '/failed[@xmlns="' + NS_SM + '"]' SM_R_REQUEST = '/r[@xmlns="' + NS_SM + '"]' SM_A_REQUEST = '/a[@xmlns="' + NS_SM + '"]' SM_H_REQUEST = '/h[@xmlns="' + NS_SM + '"]' # Max number of stanza to send before requesting ack MAX_STANZA_ACK_R = 5 # Max number of seconds before requesting ack MAX_DELAY_ACK_R = 30 MAX_COUNTER = 2**32 RESUME_MAX = 5*60 # if we don't have an answer to ACK REQUEST after this delay, connection is aborted ACK_TIMEOUT = 35 class ProfileSessionData(object): out_counter = 0 in_counter = 0 session_id = None location = None session_max = None # True when an ack answer is expected ack_requested = False last_ack_r = 0 disconnected_time = None def __init__(self, callback, **kw): self.buffer = collections.deque() self.buffer_idx = 0 self._enabled = False self.timer = None # time used when doing a ack request # when it times out, connection is aborted self.req_timer = None self.callback_data = (callback, kw) @property def enabled(self): return self._enabled @enabled.setter def enabled(self, enabled): if enabled: if self._enabled: raise exceptions.InternalError( "Stream Management can't be enabled twice") self._enabled = True callback, kw = self.callback_data self.timer = task.LoopingCall(callback, **kw) self.timer.start(MAX_DELAY_ACK_R, now=False) else: self._enabled = False if self.timer is not None: self.timer.stop() self.timer = None @property def resume_enabled(self): return self.session_id is not None def reset(self): self.enabled = False self.buffer.clear() self.buffer_idx = 0 self.in_counter = self.out_counter = 0 self.session_id = self.location = None self.ack_requested = False self.last_ack_r = 0 if self.req_timer is not None: if self.req_timer.active(): log.error("req_timer has been called/cancelled but not reset") else: self.req_timer.cancel() self.req_timer = None def getBufferCopy(self): return list(self.buffer) class XEP_0198(object): # FIXME: location is not handled yet def __init__(self, host): log.info(_("Plugin Stream Management initialization")) self.host = host host.registerNamespace('sm', NS_SM) host.trigger.add("stream_hooks", self.addHooks) host.trigger.add("xml_init", self._XMLInitTrigger) host.trigger.add("disconnecting", self._disconnectingTrigger) host.trigger.add("disconnected", self._disconnectedTrigger) try: self._ack_timeout = int(host.memory.getConfig("", "ack_timeout", ACK_TIMEOUT)) except ValueError: log.error(_("Invalid ack_timeout value, please check your configuration")) self._ack_timeout = ACK_TIMEOUT if not self._ack_timeout: log.info(_("Ack timeout disabled")) else: log.info(_("Ack timeout set to {timeout}s").format( timeout=self._ack_timeout)) def profileConnecting(self, client): client._xep_0198_session = ProfileSessionData(callback=self.checkAcks, client=client) def getHandler(self, client): return XEP_0198_handler(self) def addHooks(self, client, receive_hooks, send_hooks): """Add hooks to handle in/out stanzas counters""" receive_hooks.append(partial(self.onReceive, client=client)) send_hooks.append(partial(self.onSend, client=client)) return True def _XMLInitTrigger(self, client): """Enable or resume a stream mangement""" if not (NS_SM, 'sm') in client.xmlstream.features: log.warning(_( "Your server doesn't support stream management ({namespace}), this is " "used to improve connection problems detection (like network outages). " "Please ask your server administrator to enable this feature.".format( namespace=NS_SM))) return True session = client._xep_0198_session # a disconnect timer from a previous disconnection may still be active try: disconnect_timer = session.disconnect_timer except AttributeError: pass else: if disconnect_timer.active(): disconnect_timer.cancel() del session.disconnect_timer if session.resume_enabled: # we are resuming a session resume_elt = domish.Element((NS_SM, 'resume')) resume_elt['h'] = str(session.in_counter) resume_elt['previd'] = session.session_id client.send(resume_elt) session.resuming = True # session.enabled will be set on <resumed/> reception return False else: # we start a new session assert session.out_counter == 0 enable_elt = domish.Element((NS_SM, 'enable')) enable_elt['resume'] = 'true' client.send(enable_elt) session.enabled = True return True def _disconnectingTrigger(self, client): session = client._xep_0198_session if session.enabled: self.sendAck(client) # This is a requested disconnection, so we can reset the session # to disable resuming and close normally the stream session.reset() return True def _disconnectedTrigger(self, client, reason): if client.is_component: return True session = client._xep_0198_session session.enabled = False if session.resume_enabled: session.disconnected_time = time.time() session.disconnect_timer = reactor.callLater(session.session_max, client.disconnectProfile, reason) # disconnectProfile must not be called at this point # because session can be resumed return False else: return True def checkAcks(self, client): """Request ack if needed""" session = client._xep_0198_session # log.debug("checkAcks (in_counter={}, out_counter={}, buf len={}, buf idx={})" # .format(session.in_counter, session.out_counter, len(session.buffer), # session.buffer_idx)) if session.ack_requested or not session.buffer: return if (session.out_counter - session.buffer_idx >= MAX_STANZA_ACK_R or time.time() - session.last_ack_r >= MAX_DELAY_ACK_R): self.requestAck(client) session.ack_requested = True session.last_ack_r = time.time() def updateBuffer(self, session, server_acked): """Update buffer and buffer_index""" if server_acked > session.buffer_idx: diff = server_acked - session.buffer_idx try: for i in range(diff): session.buffer.pop() except IndexError: log.error( "error while cleaning buffer, invalid index (buffer is empty):\n" "diff = {diff}\n" "server_acked = {server_acked}\n" "buffer_idx = {buffer_id}".format( diff=diff, server_acked=server_acked, buffer_id=session.buffer_idx)) session.buffer_idx += diff def replayBuffer(self, client, buffer_, discard_results=False): """Resend all stanza in buffer @param buffer_(collection.deque, list): buffer to replay the buffer will be cleared by this method @param discard_results(bool): if True, don't replay IQ result stanzas """ while True: try: stanza = buffer_.pop() except IndexError: break else: if ((discard_results and stanza.name == 'iq' and stanza.getAttribute('type') == 'result')): continue client.send(stanza) def sendAck(self, client): """Send an answer element with current IN counter""" a_elt = domish.Element((NS_SM, 'a')) a_elt['h'] = str(client._xep_0198_session.in_counter) client.send(a_elt) def requestAck(self, client): """Send a request element""" session = client._xep_0198_session r_elt = domish.Element((NS_SM, 'r')) client.send(r_elt) if session.req_timer is not None: raise exceptions.InternalError("req_timer should not be set") if self._ack_timeout: session.req_timer = reactor.callLater(self._ack_timeout, self.onAckTimeOut, client) def _connectionFailed(self, failure_, connector): normal_host, normal_port = connector.normal_location del connector.normal_location log.warning(_( "Connection failed using location given by server (host: {host}, port: " "{port}), switching to normal host and port (host: {normal_host}, port: " "{normal_port})".format(host=connector.host, port=connector.port, normal_host=normal_host, normal_port=normal_port))) connector.host, connector.port = normal_host, normal_port connector.connectionFailed = connector.connectionFailed_ori del connector.connectionFailed_ori return connector.connectionFailed(failure_) def onEnabled(self, enabled_elt, client): session = client._xep_0198_session session.in_counter = 0 # we check that resuming is possible and that we have a session id resume = C.bool(enabled_elt.getAttribute('resume')) session_id = enabled_elt.getAttribute('id') if not session_id: log.warning(_('Incorrect <enabled/> element received, no "id" attribute')) if not resume or not session_id: log.warning(_( "You're server doesn't support session resuming with stream management, " "please contact your server administrator to enable it")) return session.session_id = session_id # XXX: we disable resource binding, which must not be done # when we resume the session. client.factory.authenticator.res_binding = False # location, in case server want resuming session to be elsewhere try: location = enabled_elt['location'] except KeyError: pass else: # TODO: handle IPv6 here (in brackets, cf. XEP) try: domain, port = location.split(':', 1) port = int(port) except ValueError: log.warning(_("Invalid location received: {location}") .format(location=location)) else: session.location = (domain, port) # we monkey patch connector to use the new location connector = client.xmlstream.transport.connector connector.normal_location = connector.host, connector.port connector.host = domain connector.port = port connector.connectionFailed_ori = connector.connectionFailed connector.connectionFailed = partial(self._connectionFailed, connector=connector) # resuming time try: max_s = int(enabled_elt['max']) except (ValueError, KeyError) as e: if isinstance(e, ValueError): log.warning(_('Invalid "max" attribute')) max_s = RESUME_MAX log.info(_("Using default session max value ({max_s} s).".format( max_s=max_s))) log.info(_("Stream Management enabled")) else: log.info(_( "Stream Management enabled, with a resumption time of {res_m:.2f} min" .format(res_m = max_s/60))) session.session_max = max_s def onResumed(self, enabled_elt, client): session = client._xep_0198_session assert not session.enabled del session.resuming server_acked = int(enabled_elt['h']) self.updateBuffer(session, server_acked) resend_count = len(session.buffer) # we resend all stanza which have not been received properly self.replayBuffer(client, session.buffer) # now we can continue the session session.enabled = True d_time = time.time() - session.disconnected_time log.info(_("Stream session resumed (disconnected for {d_time} s, {count} " "stanza(s) resent)").format(d_time=int(d_time), count=resend_count)) def onFailed(self, failed_elt, client): session = client._xep_0198_session condition_elt = failed_elt.firstChildElement() buffer_ = session.getBufferCopy() session.reset() try: del session.resuming except AttributeError: # stream management can't be started at all msg = _("Can't use stream management") if condition_elt is None: log.error(msg + '.') else: log.error(_("{msg}: {reason}").format( msg=msg, reason=condition_elt.name)) else: # only stream resumption failed, we can try full session init # XXX: we try to start full session init from this point, with many # variables/attributes already initialised with a potentially different # jid. This is experimental and may not be safe. It may be more # secured to abord the connection and restart everything with a fresh # client. msg = _("stream resumption not possible, restarting full session") if condition_elt is None: log.warning('{msg}.'.format(msg=msg)) else: log.warning("{msg}: {reason}".format( msg=msg, reason=condition_elt.name)) # stream resumption failed, but we still can do normal stream management # we restore attributes as if the session was new, and init stream # we keep everything initialized, and only do binding, roster request # and initial presence sending. if client.conn_deferred.called: client.conn_deferred = defer.Deferred() else: log.error("conn_deferred should be called at this point") plg_0045 = self.host.plugins.get('XEP-0045') plg_0313 = self.host.plugins.get('XEP-0313') # FIXME: we should call all loaded plugins with generic callbacks # (e.g. prepareResume and resume), so a hot resuming can be done # properly for all plugins. if plg_0045 is not None: # we have to remove joined rooms muc_join_args = plg_0045.popRooms(client) # we need to recreate roster client.handlers.remove(client.roster) client.roster = client.roster.__class__(self.host) client.roster.setHandlerParent(client) # bind init is not done when resuming is possible, so we have to do it now bind_init = jabber_client.BindInitializer(client.xmlstream) bind_init.required = True d = bind_init.start() # we set the jid, which may have changed d.addCallback(lambda __: setattr(client.factory.authenticator, "jid", client.jid)) # we call the trigger who will send the <enable/> element d.addCallback(lambda __: self._XMLInitTrigger(client)) # then we have to re-request the roster, as changes may have occured d.addCallback(lambda __: client.roster.requestRoster()) # we add got_roster to be sure to have roster before sending initial presence d.addCallback(lambda __: client.roster.got_roster) if plg_0313 is not None: # we retrieve one2one MAM archives d.addCallback(lambda __: defer.ensureDeferred(plg_0313.resume(client))) # initial presence must be sent manually d.addCallback(lambda __: client.presence.available()) if plg_0045 is not None: # we re-join MUC rooms muc_d_list = defer.DeferredList( [plg_0045.join(*args) for args in muc_join_args]) d.addCallback(lambda __: muc_d_list) # at the end we replay the buffer, as those stanzas have probably not # been received d.addCallback(lambda __: self.replayBuffer(client, buffer_, discard_results=True)) def onReceive(self, element, client): if not client.is_component: session = client._xep_0198_session if session.enabled and element.name.lower() in C.STANZA_NAMES: session.in_counter += 1 % MAX_COUNTER def onSend(self, obj, client): if not client.is_component: session = client._xep_0198_session if (session.enabled and domish.IElement.providedBy(obj) and obj.name.lower() in C.STANZA_NAMES): session.out_counter += 1 % MAX_COUNTER session.buffer.appendleft(obj) self.checkAcks(client) def onAckRequest(self, r_elt, client): self.sendAck(client) def onAckAnswer(self, a_elt, client): session = client._xep_0198_session session.ack_requested = False if self._ack_timeout: if session.req_timer is None: log.error("req_timer should be set") else: session.req_timer.cancel() session.req_timer = None try: server_acked = int(a_elt['h']) except ValueError: log.warning(_("Server returned invalid ack element, disabling stream " "management: {xml}").format(xml=a_elt)) session.enabled = False return if server_acked > session.out_counter: log.error(_("Server acked more stanzas than we have sent, disabling stream " "management.")) session.reset() return self.updateBuffer(session, server_acked) self.checkAcks(client) def onAckTimeOut(self, client): """Called when a requested ACK has not been received in time""" log.info(_("Ack was not received in time, aborting connection")) try: xmlstream = client.xmlstream except AttributeError: log.warning("xmlstream has already been terminated") else: transport = xmlstream.transport if transport is None: log.warning("transport was already removed") else: transport.abortConnection() client._xep_0198_session.req_timer = None @implementer(iwokkel.IDisco) class XEP_0198_handler(xmlstream.XMPPHandler): def __init__(self, plugin_parent): self.plugin_parent = plugin_parent self.host = plugin_parent.host def connectionInitialized(self): self.xmlstream.addObserver( SM_ENABLED, self.plugin_parent.onEnabled, client=self.parent ) self.xmlstream.addObserver( SM_RESUMED, self.plugin_parent.onResumed, client=self.parent ) self.xmlstream.addObserver( SM_FAILED, self.plugin_parent.onFailed, client=self.parent ) self.xmlstream.addObserver( SM_R_REQUEST, self.plugin_parent.onAckRequest, client=self.parent ) self.xmlstream.addObserver( SM_A_REQUEST, self.plugin_parent.onAckAnswer, client=self.parent ) def getDiscoInfo(self, requestor, target, nodeIdentifier=""): return [disco.DiscoFeature(NS_SM)] def getDiscoItems(self, requestor, target, nodeIdentifier=""): return []