view sat/core/patches.py @ 3013:860c550028d6

memory (sqlite): properly wait for messages to be writen in database: the deferreds of the queries writing message to databases where not gathered and returned, so the caller was not waiting for them to continue its workflow. This was resulting in messages not always written when database was read just after the write (a case common with MUC implementation), and message was appearing empty when sent to bridge. fix 328
author Goffi <goffi@goffi.org>
date Thu, 18 Jul 2019 21:58:34 +0200
parents 00d905e1b0ef
children ab2696e34d29
line wrap: on
line source

import copy
from twisted.words.protocols.jabber import xmlstream, sasl, client as tclient, jid
from twisted.internet import ssl
from wokkel import client
from sat.core.constants import Const as C
from sat.core.log import getLogger

log = getLogger(__name__)

"""This module apply monkey patches to Twisted and Wokkel
   First part handle certificate validation during XMPP connectionand are temporary
   (until merged upstream).
   Second part add a trigger point to send and onElement method of XmlStream
   """


## certificate validation patches

class TLSInitiatingInitializer(xmlstream.TLSInitiatingInitializer):
    check_certificate = True

    def onProceed(self, obj):
        self.xmlstream.removeObserver('/failure', self.onFailure)
        trustRoot = ssl.platformTrust() if self.check_certificate else None
        ctx = ssl.CertificateOptions(trustRoot=trustRoot)
        self.xmlstream.transport.startTLS(ctx)
        self.xmlstream.reset()
        self.xmlstream.sendHeader()
        self._deferred.callback(xmlstream.Reset)


class XMPPClient(client.XMPPClient):

    def __init__(self, jid, password, host=None, port=5222,
                 check_certificate=True):
        self.jid = jid
        self.domain = jid.host.encode('idna')
        self.host = host
        self.port = port

        factory = HybridClientFactory(
            jid, password, check_certificate=check_certificate)

        client.StreamManager.__init__(self, factory)


def HybridClientFactory(jid, password, check_certificate=True):
    a = HybridAuthenticator(jid, password, check_certificate)

    return xmlstream.XmlStreamFactory(a)


class HybridAuthenticator(client.HybridAuthenticator):
    res_binding = True

    def __init__(self, jid, password, check_certificate):
        xmlstream.ConnectAuthenticator.__init__(self, jid.host)
        self.jid = jid
        self.password = password
        self.check_certificate = check_certificate

    def associateWithStream(self, xs):
        xmlstream.ConnectAuthenticator.associateWithStream(self, xs)

        tlsInit = xmlstream.TLSInitiatingInitializer(xs)
        tlsInit.check_certificate = self.check_certificate
        xs.initializers = [client.client.CheckVersionInitializer(xs),
                           tlsInit,
                           CheckAuthInitializer(xs, self.res_binding)]


# XmlStream triggers


class XmlStream(xmlstream.XmlStream):
    """XmlStream which allows to add hooks"""

    def __init__(self, authenticator):
        xmlstream.XmlStream.__init__(self, authenticator)
        # hooks at this level should not modify content
        # so it's not needed to handle priority as with triggers
        self._onElementHooks = []
        self._sendHooks = []

    def addHook(self, hook_type, callback):
        """Add a send or receive hook"""
        conflict_msg = (u"Hook conflict: can't add {hook_type} hook {callback}"
            .format(hook_type=hook_type, callback=callback))
        if hook_type == C.STREAM_HOOK_RECEIVE:
            if callback not in self._onElementHooks:
                self._onElementHooks.append(callback)
            else:
                log.warning(conflict_msg)
        elif hook_type == C.STREAM_HOOK_SEND:
            if callback not in self._sendHooks:
                self._sendHooks.append(callback)
            else:
                log.warning(conflict_msg)
        else:
            raise ValueError(u"Invalid hook type: {hook_type}"
                .format(hook_type=hook_type))

    def onElement(self, element):
        for hook in self._onElementHooks:
            hook(element)
        xmlstream.XmlStream.onElement(self, element)

    def send(self, obj):
        for hook in self._sendHooks:
            hook(obj)
        xmlstream.XmlStream.send(self, obj)


# Binding activation (needed for stream management, XEP-0198)


class CheckAuthInitializer(client.CheckAuthInitializer):

    def __init__(self, xs, res_binding):
        super(CheckAuthInitializer, self).__init__(xs)
        self.res_binding = res_binding

    def initialize(self):
        # XXX: modification of client.CheckAuthInitializer which has optional
        #      resource binding, and which doesn't do deprecated
        #      SessionInitializer
        if (sasl.NS_XMPP_SASL, 'mechanisms') in self.xmlstream.features:
            inits = [(sasl.SASLInitiatingInitializer, True)]
            if self.res_binding:
                inits.append((tclient.BindInitializer, True)),

            for initClass, required in inits:
                init = initClass(self.xmlstream)
                init.required = required
                self.xmlstream.initializers.append(init)
        elif (tclient.NS_IQ_AUTH_FEATURE, 'auth') in self.xmlstream.features:
            self.xmlstream.initializers.append(
                    tclient.IQAuthInitializer(self.xmlstream))
        else:
            raise Exception("No available authentication method found")


# jid fix

def internJID(jidstring):
    """
    Return interned JID.

    @rtype: L{JID}
    """
    # XXX: this interJID return a copy of the cached jid
    #      this avoid modification of cached jid as JID is mutable
    # TODO: propose this upstream

    if jidstring in jid.__internJIDs:
        return copy.copy(jid.__internJIDs[jidstring])
    else:
        j = jid.JID(jidstring)
        jid.__internJIDs[jidstring] = j
        return copy.copy(j)


def apply():
    # certificate validation
    xmlstream.TLSInitiatingInitializer = TLSInitiatingInitializer
    client.XMPPClient = XMPPClient
    # XmlStream triggers
    xmlstream.XmlStreamFactory.protocol = XmlStream
    # jid fix
    jid.internJID = internJID