--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sat/plugins/plugin_xep_0234.py	Mon Apr 02 19:44:50 2018 +0200
@@ -0,0 +1,633 @@
+#!/usr/bin/env python2
+# -*- coding: utf-8 -*-
+
+# SAT plugin for Jingle File Transfer (XEP-0234)
+# Copyright (C) 2009-2018 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.log import getLogger
+log = getLogger(__name__)
+from sat.core import exceptions
+from wokkel import disco, iwokkel
+from zope.interface import implements
+from sat.tools import utils
+from sat.tools import stream
+import os.path
+from twisted.words.xish import domish
+from twisted.words.protocols.jabber import jid
+from twisted.python import failure
+from twisted.words.protocols.jabber.xmlstream import XMPPHandler
+from twisted.internet import defer
+from twisted.internet import reactor
+from twisted.internet import error as internet_error
+from collections import namedtuple
+from sat.tools.common import regex
+import mimetypes
+
+
+NS_JINGLE_FT = 'urn:xmpp:jingle:apps:file-transfer:5'
+
+PLUGIN_INFO = {
+    C.PI_NAME: "Jingle File Transfer",
+    C.PI_IMPORT_NAME: "XEP-0234",
+    C.PI_TYPE: "XEP",
+    C.PI_MODES: C.PLUG_MODE_BOTH,
+    C.PI_PROTOCOLS: ["XEP-0234"],
+    C.PI_DEPENDENCIES: ["XEP-0166", "XEP-0300", "FILE"],
+    C.PI_MAIN: "XEP_0234",
+    C.PI_HANDLER: "yes",
+    C.PI_DESCRIPTION: _("""Implementation of Jingle File Transfer""")
+}
+
+EXTRA_ALLOWED = {u'path', u'namespace', u'file_desc', u'file_hash'}
+Range = namedtuple('Range', ('offset', 'length'))
+
+
+class XEP_0234(object):
+    # TODO: assure everything is closed when file is sent or session terminate is received
+    # TODO: call self._f.unregister when unloading order will be managing (i.e. when dependencies will be unloaded at the end)
+    Range = Range  # we copy the class here, so it can be used by other plugins
+
+    def __init__(self, host):
+        log.info(_("plugin Jingle File Transfer initialization"))
+        self.host = host
+        host.registerNamespace('jingle-ft', NS_JINGLE_FT)
+        self._j = host.plugins["XEP-0166"] # shortcut to access jingle
+        self._j.registerApplication(NS_JINGLE_FT, self)
+        self._f = host.plugins["FILE"]
+        self._f.register(NS_JINGLE_FT, self.fileJingleSend, priority = 10000, method_name=u"Jingle")
+        self._hash = self.host.plugins["XEP-0300"]
+        host.bridge.addMethod("fileJingleSend", ".plugin", in_sign='ssssa{ss}s', out_sign='', method=self._fileJingleSend, async=True)
+        host.bridge.addMethod("fileJingleRequest", ".plugin", in_sign='sssssa{ss}s', out_sign='s', method=self._fileJingleRequest, async=True)
+
+    def getHandler(self, client):
+        return XEP_0234_handler()
+
+    def getProgressId(self, session, content_name):
+        """Return a unique progress ID
+
+        @param session(dict): jingle session
+        @param content_name(unicode): name of the content
+        @return (unicode): unique progress id
+        """
+        return u'{}_{}'.format(session['id'], content_name)
+
+    # generic methods
+
+    def buildFileElement(self, name, file_hash=None, hash_algo=None, size=None, mime_type=None, desc=None,
+                         modified=None, transfer_range=None, path=None, namespace=None, file_elt=None, **kwargs):
+        """Generate a <file> element with available metadata
+
+        @param file_hash(unicode, None): hash of the file
+            empty string to set <hash-used/> element
+        @param hash_algo(unicode, None): hash algorithm used
+            if file_hash is None and hash_algo is set, a <hash-used/> element will be generated
+        @param transfer_range(Range, None): where transfer must start/stop
+        @param modified(int, unicode, None): date of last modification
+            0 to use current date
+            int to use an unix timestamp
+            else must be an unicode string which will be used as it (it must be an XMPP time)
+        @param file_elt(domish.Element, None): element to use
+            None to create a new one
+        @param **kwargs: data for plugin extension (ignored by default)
+        @return (domish.Element): generated element
+        @trigger XEP-0234_buildFileElement(file_elt, extra_args): can be used to extend elements to add
+        """
+        if file_elt is None:
+            file_elt = domish.Element((NS_JINGLE_FT, u'file'))
+        for name, value in ((u'name', name), (u'size', size), ('media-type', mime_type),
+                            (u'desc', desc), (u'path', path), (u'namespace', namespace)):
+            if value is not None:
+                file_elt.addElement(name, content=unicode(value))
+
+        if modified is not None:
+            if isinstance(modified, int):
+                file_elt.addElement(u'date', utils.xmpp_date(modified or None))
+            else:
+                file_elt.addElement(u'date', modified)
+        elif 'created' in kwargs:
+            file_elt.addElement(u'date', utils.xmpp_date(kwargs.pop('created')))
+
+        range_elt = file_elt.addElement(u'range')
+        if transfer_range is not None:
+            if transfer_range.offset is not None:
+                range_elt[u'offset'] = transfer_range.offset
+            if transfer_range.length is not None:
+                range_elt[u'length'] = transfer_range.length
+        if file_hash is not None:
+            if not file_hash:
+                file_elt.addChild(self._hash.buildHashUsedElt())
+            else:
+                file_elt.addChild(self._hash.buildHashElt(file_hash, hash_algo))
+        elif hash_algo is not None:
+            file_elt.addChild(self._hash.buildHashUsedElt(hash_algo))
+        self.host.trigger.point(u'XEP-0234_buildFileElement', file_elt, extra_args=kwargs)
+        if kwargs:
+            for kw in kwargs:
+                log.debug('ignored keyword: {}'.format(kw))
+        return file_elt
+
+    def buildFileElementFromDict(self, file_data, **kwargs):
+        """like buildFileElement but get values from a file_data dict
+
+        @param file_data(dict): metadata to use
+        @param **kwargs: data to override
+        """
+        if kwargs:
+            file_data = file_data.copy()
+            file_data.update(kwargs)
+        return self. buildFileElement(**file_data)
+
+
+    def parseFileElement(self, file_elt, file_data=None, given=False, parent_elt=None, keep_empty_range=False):
+        """Parse a <file> element and file dictionary accordingly
+
+        @param file_data(dict, None): dict where the data will be set
+            following keys will be set (and overwritten if they already exist):
+                name, file_hash, hash_algo, size, mime_type, desc, path, namespace, range
+            if None, a new dict is created
+        @param given(bool): if True, prefix hash key with "given_"
+        @param parent_elt(domish.Element, None): parent of the file element
+            if set, file_elt must not be set
+        @param keep_empty_range(bool): if True, keep empty range (i.e. range when offset and length are None)
+            empty range are useful to know if a peer_jid can handle range
+        @return (dict): file_data
+        @trigger XEP-0234_parseFileElement(file_elt, file_data): can be used to parse new elements
+        @raise exceptions.NotFound: there is not <file> element in parent_elt
+        @raise exceptions.DataError: if file_elt uri is not NS_JINGLE_FT
+        """
+        if parent_elt is not None:
+            if file_elt is not None:
+                raise exceptions.InternalError(u'file_elt must be None if parent_elt is set')
+            try:
+                file_elt = next(parent_elt.elements(NS_JINGLE_FT, u'file'))
+            except StopIteration:
+                raise exceptions.NotFound()
+        else:
+            if not file_elt or file_elt.uri != NS_JINGLE_FT:
+                raise exceptions.DataError(u'invalid <file> element: {stanza}'.format(stanza = file_elt.toXml()))
+
+        if file_data is None:
+            file_data = {}
+
+        for name in (u'name', u'desc',  u'path', u'namespace'):
+            try:
+                file_data[name] = unicode(next(file_elt.elements(NS_JINGLE_FT, name)))
+            except StopIteration:
+                pass
+
+
+        name = file_data.get(u'name')
+        if name == u'..':
+            # we don't want to go to parent dir when joining to a path
+            name = u'--'
+            file_data[u'name'] = name
+        elif name is not None and u'/' in name or u'\\' in name:
+            file_data[u'name'] = regex.pathEscape(name)
+
+        try:
+            file_data[u'mime_type'] = unicode(next(file_elt.elements(NS_JINGLE_FT, u'media-type')))
+        except StopIteration:
+            pass
+
+        try:
+            file_data[u'size'] = int(unicode(next(file_elt.elements(NS_JINGLE_FT, u'size'))))
+        except StopIteration:
+            pass
+
+        try:
+            file_data[u'modified'] = utils.date_parse(next(file_elt.elements(NS_JINGLE_FT, u'date')))
+        except StopIteration:
+            pass
+
+        try:
+            range_elt = file_elt.elements(NS_JINGLE_FT, u'range').next()
+        except StopIteration:
+            pass
+        else:
+            offset = range_elt.getAttribute('offset')
+            length = range_elt.getAttribute('length')
+            if offset or length or keep_empty_range:
+                file_data[u'transfer_range'] = Range(offset=offset, length=length)
+
+        prefix = u'given_' if given else u''
+        hash_algo_key, hash_key = u'hash_algo', prefix + u'file_hash'
+        try:
+            file_data[hash_algo_key], file_data[hash_key] = self._hash.parseHashElt(file_elt)
+        except exceptions.NotFound:
+            pass
+
+        self.host.trigger.point(u'XEP-0234_parseFileElement', file_elt, file_data)
+
+        return file_data
+
+    # bridge methods
+
+    def _fileJingleSend(self, peer_jid, filepath, name="", file_desc="", extra=None, profile=C.PROF_KEY_NONE):
+        client = self.host.getClient(profile)
+        return self.fileJingleSend(client, jid.JID(peer_jid), filepath, name or None, file_desc or None, extra or None)
+
+    @defer.inlineCallbacks
+    def fileJingleSend(self, client, peer_jid, filepath, name, file_desc=None, extra=None):
+        """Send a file using jingle file transfer
+
+        @param peer_jid(jid.JID): destinee jid
+        @param filepath(str): absolute path of the file
+        @param name(unicode, None): name of the file
+        @param file_desc(unicode, None): description of the file
+        @return (D(unicode)): progress id
+        """
+        progress_id_d = defer.Deferred()
+        if extra is None:
+            extra = {}
+        if file_desc is not None:
+            extra['file_desc'] = file_desc
+        yield self._j.initiate(client,
+                               peer_jid,
+                               [{'app_ns': NS_JINGLE_FT,
+                                 'senders': self._j.ROLE_INITIATOR,
+                                 'app_kwargs': {'filepath': filepath,
+                                                'name': name,
+                                                'extra': extra,
+                                                'progress_id_d': progress_id_d},
+                               }])
+        progress_id = yield progress_id_d
+        defer.returnValue(progress_id)
+
+    def _fileJingleRequest(self, peer_jid, filepath, name="", file_hash="", hash_algo="", extra=None, profile=C.PROF_KEY_NONE):
+        client = self.host.getClient(profile)
+        return self.fileJingleRequest(client, jid.JID(peer_jid), filepath, name or None, file_hash or None, hash_algo or None, extra or None)
+
+    @defer.inlineCallbacks
+    def fileJingleRequest(self, client, peer_jid, filepath, name=None, file_hash=None, hash_algo=None, extra=None):
+        """Request a file using jingle file transfer
+
+        @param peer_jid(jid.JID): destinee jid
+        @param filepath(str): absolute path of the file
+        @param name(unicode, None): name of the file
+        @param file_hash(unicode, None): hash of the file
+        @return (D(unicode)): progress id
+        """
+        progress_id_d = defer.Deferred()
+        if extra is None:
+            extra = {}
+        if file_hash is not None:
+            if hash_algo is None:
+                raise ValueError(_(u"hash_algo must be set if file_hash is set"))
+            extra['file_hash'] = file_hash
+            extra['hash_algo'] = hash_algo
+        else:
+            if hash_algo is not None:
+                raise ValueError(_(u"file_hash must be set if hash_algo is set"))
+        yield self._j.initiate(client,
+                               peer_jid,
+                               [{'app_ns': NS_JINGLE_FT,
+                                 'senders': self._j.ROLE_RESPONDER,
+                                 'app_kwargs': {'filepath': filepath,
+                                                'name': name,
+                                                'extra': extra,
+                                                'progress_id_d': progress_id_d},
+                               }])
+        progress_id = yield progress_id_d
+        defer.returnValue(progress_id)
+
+    # jingle callbacks
+
+    def jingleSessionInit(self, client, session, content_name, filepath, name, extra, progress_id_d):
+        if extra is None:
+            extra = {}
+        else:
+            if not EXTRA_ALLOWED.issuperset(extra):
+                raise ValueError(_(u"only the following keys are allowed in extra: {keys}").format(
+                    keys=u', '.join(EXTRA_ALLOWED)))
+        progress_id_d.callback(self.getProgressId(session, content_name))
+        content_data = session['contents'][content_name]
+        application_data = content_data['application_data']
+        assert 'file_path' not in application_data
+        application_data['file_path'] = filepath
+        file_data = application_data['file_data'] = {}
+        desc_elt = domish.Element((NS_JINGLE_FT, 'description'))
+        file_elt = desc_elt.addElement("file")
+
+        if content_data[u'senders'] == self._j.ROLE_INITIATOR:
+            # we send a file
+            if name is None:
+                name = os.path.basename(filepath)
+            file_data[u'date'] = utils.xmpp_date()
+            file_data[u'desc'] = extra.pop(u'file_desc', u'')
+            file_data[u'name'] = name
+            mime_type = mimetypes.guess_type(name, strict=False)[0]
+            if mime_type is not None:
+                file_data[u'mime_type'] = mime_type
+            file_data[u'size'] = os.path.getsize(filepath)
+            if u'namespace' in extra:
+                file_data[u'namespace'] = extra[u'namespace']
+            if u'path' in extra:
+                file_data[u'path'] = extra[u'path']
+            self.buildFileElementFromDict(file_data, file_elt=file_elt, file_hash=u'')
+        else:
+            # we request a file
+            file_hash = extra.pop(u'file_hash', u'')
+            if not name and not file_hash:
+                raise ValueError(_(u'you need to provide at least name or file hash'))
+            if name:
+                file_data[u'name'] = name
+            if file_hash:
+                file_data[u'file_hash'] = file_hash
+                file_data[u'hash_algo'] = extra[u'hash_algo']
+            else:
+                file_data[u'hash_algo'] = self._hash.getDefaultAlgo()
+            if u'namespace' in extra:
+                file_data[u'namespace'] = extra[u'namespace']
+            if u'path' in extra:
+                file_data[u'path'] = extra[u'path']
+            self.buildFileElementFromDict(file_data, file_elt=file_elt)
+
+        return desc_elt
+
+    def jingleRequestConfirmation(self, client, action, session, content_name, desc_elt):
+        """This method request confirmation for a jingle session"""
+        content_data = session['contents'][content_name]
+        senders = content_data[u'senders']
+        if senders not in (self._j.ROLE_INITIATOR, self._j.ROLE_RESPONDER):
+            log.warning(u"Bad sender, assuming initiator")
+            senders = content_data[u'senders'] = self._j.ROLE_INITIATOR
+        # first we grab file informations
+        try:
+            file_elt = desc_elt.elements(NS_JINGLE_FT, 'file').next()
+        except StopIteration:
+            raise failure.Failure(exceptions.DataError)
+        file_data = {'progress_id': self.getProgressId(session, content_name)}
+
+        if senders == self._j.ROLE_RESPONDER:
+            # we send the file
+            return self._fileSendingRequestConf(client, session, content_data, content_name, file_data, file_elt)
+        else:
+            # we receive the file
+            return self._fileReceivingRequestConf(client, session, content_data, content_name, file_data, file_elt)
+
+    @defer.inlineCallbacks
+    def _fileSendingRequestConf(self, client, session, content_data, content_name, file_data, file_elt):
+        """parse file_elt, and handle file retrieving/permission checking"""
+        self.parseFileElement(file_elt, file_data)
+        content_data['application_data']['file_data'] = file_data
+        finished_d = content_data['finished_d'] = defer.Deferred()
+
+        # confirmed_d is a deferred returning confimed value (only used if cont is False)
+        cont, confirmed_d = self.host.trigger.returnPoint("XEP-0234_fileSendingRequest", client, session, content_data, content_name, file_data, file_elt)
+        if not cont:
+            confirmed = yield confirmed_d
+            if confirmed:
+                args = [client, session, content_name, content_data]
+                finished_d.addCallbacks(self._finishedCb, self._finishedEb, args, None, args)
+            defer.returnValue(confirmed)
+
+        log.warning(_(u'File continue is not implemented yet'))
+        defer.returnValue(False)
+
+    def _fileReceivingRequestConf(self, client, session, content_data, content_name, file_data, file_elt):
+        """parse file_elt, and handle user permission/file opening"""
+        self.parseFileElement(file_elt, file_data, given=True)
+        try:
+            hash_algo, file_data['given_file_hash'] = self._hash.parseHashElt(file_elt)
+        except exceptions.NotFound:
+            try:
+                hash_algo = self._hash.parseHashUsedElt(file_elt)
+            except exceptions.NotFound:
+                raise failure.Failure(exceptions.DataError)
+
+        if hash_algo is not None:
+            file_data['hash_algo'] = hash_algo
+            file_data['hash_hasher'] = hasher = self._hash.getHasher(hash_algo)
+            file_data['data_cb'] = lambda data: hasher.update(data)
+
+        try:
+            file_data['size'] = int(file_data['size'])
+        except ValueError:
+            raise failure.Failure(exceptions.DataError)
+
+        name = file_data['name']
+        if '/' in name or '\\' in name:
+            log.warning(u"File name contain path characters, we replace them: {}".format(name))
+            file_data['name'] = name.replace('/', '_').replace('\\', '_')
+
+        content_data['application_data']['file_data'] = file_data
+
+        # now we actualy request permission to user
+        def gotConfirmation(confirmed):
+            if confirmed:
+                args = [client, session, content_name, content_data]
+                finished_d.addCallbacks(self._finishedCb, self._finishedEb, args, None, args)
+            return confirmed
+
+        # deferred to track end of transfer
+        finished_d = content_data['finished_d'] = defer.Deferred()
+        d = self._f.getDestDir(client, session['peer_jid'], content_data, file_data, stream_object=True)
+        d.addCallback(gotConfirmation)
+        return d
+
+    def jingleHandler(self, client, action, session, content_name, desc_elt):
+        content_data = session['contents'][content_name]
+        application_data = content_data['application_data']
+        if action in (self._j.A_ACCEPTED_ACK,):
+            pass
+        elif action == self._j.A_SESSION_INITIATE:
+            file_elt = desc_elt.elements(NS_JINGLE_FT, 'file').next()
+            try:
+                file_elt.elements(NS_JINGLE_FT, 'range').next()
+            except StopIteration:
+                # initiator doesn't manage <range>, but we do so we advertise it
+                # FIXME: to be checked
+                log.debug("adding <range> element")
+                file_elt.addElement('range')
+        elif action == self._j.A_SESSION_ACCEPT:
+            assert not 'stream_object' in content_data
+            file_data = application_data['file_data']
+            file_path = application_data['file_path']
+            senders = content_data[u'senders']
+            if senders != session[u'role']:
+                # we are receiving the file
+                try:
+                    # did the responder specified the size of the file?
+                    file_elt = next(desc_elt.elements(NS_JINGLE_FT, u'file'))
+                    size_elt = next(file_elt.elements(NS_JINGLE_FT, u'size'))
+                    size = int(unicode(size_elt))
+                except (StopIteration, ValueError):
+                    size = None
+                # XXX: hash security is not critical here, so we just take the higher mandatory one
+                hasher = file_data['hash_hasher'] = self._hash.getHasher()
+                content_data['stream_object'] = stream.FileStreamObject(
+                    self.host,
+                    client,
+                    file_path,
+                    mode='wb',
+                    uid=self.getProgressId(session, content_name),
+                    size=size,
+                    data_cb=lambda data: hasher.update(data),
+                    )
+            else:
+                # we are sending the file
+                size = file_data['size']
+                # XXX: hash security is not critical here, so we just take the higher mandatory one
+                hasher = file_data['hash_hasher'] = self._hash.getHasher()
+                content_data['stream_object'] = stream.FileStreamObject(
+                    self.host,
+                    client,
+                    file_path,
+                    uid=self.getProgressId(session, content_name),
+                    size=size,
+                    data_cb=lambda data: hasher.update(data),
+                    )
+            finished_d = content_data['finished_d'] = defer.Deferred()
+            args = [client, session, content_name, content_data]
+            finished_d.addCallbacks(self._finishedCb, self._finishedEb, args, None, args)
+        else:
+            log.warning(u"FIXME: unmanaged action {}".format(action))
+        return desc_elt
+
+    def jingleSessionInfo(self, client, action, session, content_name, jingle_elt):
+        """Called on session-info action
+
+        manage checksum, and ignore <received/> element
+        """
+        # TODO: manage <received/> element
+        content_data = session['contents'][content_name]
+        elts = [elt for elt in jingle_elt.elements() if elt.uri == NS_JINGLE_FT]
+        if not elts:
+            return
+        for elt in elts:
+            if elt.name == 'received':
+                pass
+            elif elt.name == 'checksum':
+                # we have received the file hash, we need to parse it
+                if content_data['senders'] == session['role']:
+                    log.warning(u"unexpected checksum received while we are the file sender")
+                    raise exceptions.DataError
+                info_content_name = elt['name']
+                if info_content_name != content_name:
+                    # it was for an other content...
+                    return
+                file_data = content_data['application_data']['file_data']
+                try:
+                    file_elt = elt.elements((NS_JINGLE_FT, 'file')).next()
+                except StopIteration:
+                    raise exceptions.DataError
+                algo, file_data['given_file_hash'] = self._hash.parseHashElt(file_elt)
+                if algo != file_data.get('hash_algo'):
+                    log.warning(u"Hash algorithm used in given hash ({peer_algo}) doesn't correspond to the one we have used ({our_algo}) [{profile}]"
+                        .format(peer_algo=algo, our_algo=file_data.get('hash_algo'), profile=client.profile))
+                else:
+                    self._receiverTryTerminate(client, session, content_name, content_data)
+            else:
+                raise NotImplementedError
+
+    def jingleTerminate(self, client, action, session, content_name, jingle_elt):
+        if jingle_elt.decline:
+            # progress is the only way to tell to frontends that session has been declined
+            progress_id = self.getProgressId(session, content_name)
+            self.host.bridge.progressError(progress_id, C.PROGRESS_ERROR_DECLINED, client.profile)
+
+    def _sendCheckSum(self, client, session, content_name, content_data):
+        """Send the session-info with the hash checksum"""
+        file_data = content_data['application_data']['file_data']
+        hasher = file_data['hash_hasher']
+        hash_ = hasher.hexdigest()
+        log.debug(u"Calculated hash: {}".format(hash_))
+        iq_elt, jingle_elt = self._j.buildSessionInfo(client, session)
+        checksum_elt = jingle_elt.addElement((NS_JINGLE_FT, 'checksum'))
+        checksum_elt['creator'] = content_data['creator']
+        checksum_elt['name'] = content_name
+        file_elt = checksum_elt.addElement('file')
+        file_elt.addChild(self._hash.buildHashElt(hash_))
+        iq_elt.send()
+
+    def _receiverTryTerminate(self, client, session, content_name, content_data, last_try=False):
+        """Try to terminate the session
+
+        This method must only be used by the receiver.
+        It check if transfer is finished, and hash available,
+        if everything is OK, it check hash and terminate the session
+        @param last_try(bool): if True this mean than session must be terminated even given hash is not available
+        @return (bool): True if session was terminated
+        """
+        if not content_data.get('transfer_finished', False):
+            return False
+        file_data = content_data['application_data']['file_data']
+        given_hash = file_data.get('given_file_hash')
+        if given_hash is None:
+            if last_try:
+                log.warning(u"sender didn't sent hash checksum, we can't check the file [{profile}]".format(profile=client.profile))
+                self._j.delayedContentTerminate(client, session, content_name)
+                content_data['stream_object'].close()
+                return True
+            return False
+        hasher = file_data['hash_hasher']
+        hash_ = hasher.hexdigest()
+
+        if hash_ == given_hash:
+            log.info(u"Hash checked, file was successfully transfered: {}".format(hash_))
+            progress_metadata = {'hash': hash_,
+                                 'hash_algo': file_data['hash_algo'],
+                                 'hash_verified': C.BOOL_TRUE
+                                }
+            error = None
+        else:
+            log.warning(u"Hash mismatch, the file was not transfered correctly")
+            progress_metadata=None
+            error = u"Hash mismatch: given={algo}:{given}, calculated={algo}:{our}".format(
+                algo = file_data['hash_algo'],
+                given = given_hash,
+                our = hash_)
+
+        self._j.delayedContentTerminate(client, session, content_name)
+        content_data['stream_object'].close(progress_metadata, error)
+        # we may have the last_try timer still active, so we try to cancel it
+        try:
+            content_data['last_try_timer'].cancel()
+        except (KeyError, internet_error.AlreadyCalled):
+            pass
+        return True
+
+    def _finishedCb(self, dummy, client, session, content_name, content_data):
+        log.info(u"File transfer terminated")
+        if content_data['senders'] != session['role']:
+            # we terminate the session only if we are the receiver,
+            # as recommanded in XEP-0234 §2 (after example 6)
+            content_data['transfer_finished'] = True
+            if not self._receiverTryTerminate(client, session, content_name, content_data):
+                # we have not received the hash yet, we wait 5 more seconds
+                content_data['last_try_timer'] = reactor.callLater(
+                    5, self._receiverTryTerminate, client, session, content_name, content_data, last_try=True)
+        else:
+            # we are the sender, we send the checksum
+            self._sendCheckSum(client, session, content_name, content_data)
+            content_data['stream_object'].close()
+
+    def _finishedEb(self, failure, client, session, content_name, content_data):
+        log.warning(u"Error while streaming file: {}".format(failure))
+        content_data['stream_object'].close()
+        self._j.contentTerminate(client, session, content_name, reason=self._j.REASON_FAILED_TRANSPORT)
+
+
+class XEP_0234_handler(XMPPHandler):
+    implements(iwokkel.IDisco)
+
+    def getDiscoInfo(self, requestor, target, nodeIdentifier=''):
+        return [disco.DiscoFeature(NS_JINGLE_FT)]
+
+    def getDiscoItems(self, requestor, target, nodeIdentifier=''):
+        return []