#!/usr/bin/env python3
# Libervia plugin for Jingle (XEP-0176)
# Copyright (C) 2009-2026 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 .
from typing import List
import uuid
from twisted.internet import defer
from twisted.words.protocols.jabber.xmlstream import XMPPHandler
from twisted.words.xish import domish
from tx_xmpp import disco, itx_xmpp
from zope.interface import implementer
from libervia.backend.core import exceptions
from libervia.backend.core.constants import Const as C
from libervia.backend.core.core_types import SatXMPPEntity
from libervia.backend.core.i18n import _
from libervia.backend.core.log import getLogger
from libervia.backend.tools.common import data_format
from .plugin_xep_0166 import BaseTransportHandler
log = getLogger(__name__)
NS_JINGLE_ICE_UDP = "urn:xmpp:jingle:transports:ice-udp:1"
PLUGIN_INFO = {
C.PI_NAME: "Jingle ICE-UDP Transport Method",
C.PI_IMPORT_NAME: "XEP-0176",
C.PI_TYPE: "XEP",
C.PI_MODES: C.PLUG_MODE_BOTH,
C.PI_PROTOCOLS: ["XEP-0176"],
C.PI_DEPENDENCIES: ["XEP-0166"],
C.PI_RECOMMENDATIONS: [],
C.PI_MAIN: "XEP_0176",
C.PI_HANDLER: "yes",
C.PI_DESCRIPTION: _("""Implementation of Jingle ICE-UDP transport"""),
}
class XEP_0176(BaseTransportHandler):
namespace = NS_JINGLE_ICE_UDP
def __init__(self, host):
log.info(f"plugin {PLUGIN_INFO[C.PI_NAME]!r} initialization")
self.host = host
self._j = host.plugins["XEP-0166"] # shortcut to access jingle
self._j.register_transport(
NS_JINGLE_ICE_UDP, self._j.TRANSPORT_DATAGRAM, self, 100
)
host.bridge.add_method(
"ice_candidates_add",
".plugin",
in_sign="sss",
out_sign="",
method=self._ice_candidates_add,
async_=True,
)
host.bridge.add_signal(
"ice_candidates_new", ".plugin", signature="sss"
) # args: jingle_sid, candidates_serialised, profile
host.bridge.add_signal(
"ice_restart", ".plugin", signature="sss"
) # args: jingle_sid, side ("local" or "peer"), profile
def get_handler(self, client):
return XEP_0176_handler()
def _ice_candidates_add(
self,
session_id: str,
media_ice_data_s: str,
profile_key: str,
):
client = self.host.get_client(profile_key)
return defer.ensureDeferred(
self.ice_candidates_add(
client,
session_id,
data_format.deserialise(media_ice_data_s),
)
)
def build_transport(
self, ice_data: dict, add_trickle: bool = False
) -> domish.Element:
"""Generate element from ICE data
@param ice_data: a dict containing the following keys:
- "ufrag" (str): The ICE username fragment.
- "pwd" (str): The ICE password.
- "candidates" (List[dict]): A list of ICE candidate dictionaries, each
containing:
- "component_id" (int): The component ID.
- "foundation" (str): The candidate foundation.
- "address" (str): The candidate IP address.
- "port" (int): The candidate port.
- "priority" (int): The candidate priority.
- "transport" (str): The candidate transport protocol, e.g., "udp".
- "type" (str): The candidate type, e.g., "host", "srflx", "prflx", or
"relay".
- "generation" (str, optional): The candidate generation. Defaults to "0".
- "network" (str, optional): The candidate network. Defaults to "0".
- "rel_addr" (str, optional): The related address for the candidate, if
any.
- "rel_port" (int, optional): The related port for the candidate, if any.
@return: A element.
"""
try:
ufrag: str = ice_data["ufrag"]
pwd: str = ice_data["pwd"]
except KeyError as e:
raise exceptions.DataError(f"ICE {e} must be provided")
candidates: List[dict] = ice_data.get("candidates", [])
candidates.sort(key=lambda c: int(c.get("priority", 0)), reverse=True)
transport_elt = domish.Element(
(NS_JINGLE_ICE_UDP, "transport"), attribs={"ufrag": ufrag, "pwd": pwd}
)
for candidate in candidates:
try:
candidate_elt = transport_elt.addElement("candidate")
candidate_elt["component"] = str(candidate["component_id"])
candidate_elt["foundation"] = candidate["foundation"]
candidate_elt["generation"] = str(candidate.get("generation", "0"))
candidate_elt["id"] = candidate.get("id") or str(uuid.uuid4())
candidate_elt["ip"] = candidate["address"]
candidate_elt["network"] = str(candidate.get("network", "0"))
candidate_elt["port"] = str(candidate["port"])
candidate_elt["priority"] = str(candidate["priority"])
candidate_elt["protocol"] = candidate["transport"]
candidate_elt["type"] = candidate["type"]
except KeyError as e:
raise exceptions.DataError(
f"Mandatory ICE candidate attribute {e} is missing"
)
if "rel_addr" in candidate and "rel_port" in candidate:
candidate_elt["rel-addr"] = candidate["rel_addr"]
candidate_elt["rel-port"] = str(candidate["rel_port"])
if add_trickle:
transport_elt.addElement(
(
"http://gultsch.de/xmpp/drafts/jingle/transports/ice-udp/option",
"trickle",
)
)
self.host.trigger.point("XEP-0176_build_transport", transport_elt, ice_data)
return transport_elt
def parse_transport(self, transport_elt: domish.Element) -> dict:
"""Parse to a dict
@param transport_elt: element
@return: ICE data (as in [build_transport])
"""
try:
ice_data = {"ufrag": transport_elt["ufrag"], "pwd": transport_elt["pwd"]}
except KeyError as e:
raise exceptions.DataError(
f" is missing mandatory attribute {e}: {transport_elt.toXml()}"
)
ice_data["candidates"] = ice_candidates = []
for candidate_elt in transport_elt.elements(NS_JINGLE_ICE_UDP, "candidate"):
try:
candidate = {
"component_id": int(candidate_elt["component"]),
"foundation": candidate_elt["foundation"],
"address": candidate_elt["ip"],
"port": int(candidate_elt["port"]),
"priority": int(candidate_elt["priority"]),
"transport": candidate_elt["protocol"],
"type": candidate_elt["type"],
}
except KeyError as e:
raise exceptions.DataError(
f"Mandatory attribute {e} is missing in candidate element"
)
if candidate_elt.hasAttribute("generation"):
candidate["generation"] = candidate_elt["generation"]
if candidate_elt.hasAttribute("network"):
candidate["network"] = candidate_elt["network"]
if candidate_elt.hasAttribute("rel-addr"):
candidate["rel_addr"] = candidate_elt["rel-addr"]
if candidate_elt.hasAttribute("rel-port"):
candidate["rel_port"] = int(candidate_elt["rel-port"])
ice_candidates.append(candidate)
self.host.trigger.point("XEP-0176_parse_transport", transport_elt, ice_data)
return ice_data
async def jingle_session_init(
self,
client: SatXMPPEntity,
session: dict,
content_name: str,
) -> domish.Element:
"""Create a Jingle session initiation transport element with ICE candidates.
@param client: SatXMPPEntity object representing the client.
@param session: Dictionary containing session data.
@param content_name: Name of the content.
@param ufrag: ICE username fragment.
@param pwd: ICE password.
@param candidates: List of ICE candidate dictionaries parsed from the
parse_ice_candidate method.
@return: domish.Element representing the Jingle transport element.
@raise exceptions.DataError: If mandatory data is missing from the candidates.
"""
content_data = session["contents"][content_name]
transport_data = content_data["transport_data"]
ice_data = transport_data["local_ice_data"]
return self.build_transport(ice_data, add_trickle=True)
async def _send_ice_buffer(
self,
client: SatXMPPEntity,
session: dict,
content_name: str,
content_data: dict,
) -> None:
"""Send ``transport-info`` actions with buffered ICE candidates.
@param client: Libervia client instance.
@param session: Jingle session.
@param content_name: Name (ID) of the content.
@param content_data: Data of the content.
"""
media_type = content_data["application_data"].get("media")
# we check if we have any buffered ICE candidates, and send them if it's the case
buffer = session.get("XEP-0176_ice_buffer")
if not buffer:
return
buffered_ice_data = buffer.pop(content_name, None)
if buffered_ice_data is None:
# legacy frontends key the buffer by media type
buffered_ice_data = buffer.pop(media_type, None)
if buffered_ice_data is None:
return
if not buffer:
del session["XEP-0176_ice_buffer"]
local_jid = session["local_jid"]
peer_jid = session["peer_jid"]
log.debug(f"Replaying ICE buffer from {local_jid} to {peer_jid}")
transport_elt = self.build_transport(buffered_ice_data)
iq_elt, __ = self._j.build_action(
client,
self._j.A_TRANSPORT_INFO,
session,
content_name,
context_elt=transport_elt,
)
self.host.trigger.point(
"XEP-0176_jingle_handler_send_buffer",
client,
session,
content_name,
content_data,
transport_elt,
iq_elt,
)
await iq_elt.send()
async def jingle_handler(
self,
client: SatXMPPEntity,
action: str,
session: dict,
content_name: str,
transport_elt: domish.Element,
) -> domish.Element:
"""Handle Jingle requests
@param client: The SatXMPPEntity instance.
@param action: The action to be performed with the session.
@param session: A dictionary containing the session information.
@param content_name: The name of the content.
@param transport_elt: The domish.Element instance representing the transport
element.
@return: element
"""
content_data = session["contents"][content_name]
transport_data = content_data["transport_data"]
if action in (
self._j.A_PREPARE_CONFIRMATION,
self._j.A_PREPARE_INITIATOR,
# a content-add comes with the peer transport, we parse it as well
self._j.A_CONTENT_ADD,
):
peer_ice_data = self.parse_transport(transport_elt)
transport_data["peer_ice_data"] = peer_ice_data
elif action == self._j.A_CONTENT_MODIFY:
# only the senders attribute is changed, nothing to do here
pass
elif action == self._j.A_ACCEPTED_ACK:
buffer = session.pop("XEP-0176_handler_buffer", None)
if buffer:
log.debug("replaying buffered events")
for args in buffer:
await self.jingle_handler(*args)
await self._send_ice_buffer(client, session, content_name, content_data)
elif action == self._j.A_PREPARE_RESPONDER:
pass
elif action == self._j.A_SESSION_ACCEPT:
await self._send_ice_buffer(client, session, content_name, content_data)
elif action == self._j.A_START:
pass
elif action == self._j.A_SESSION_INITIATE:
# responder side, we give our candidates
transport_elt = self.build_transport(
transport_data["local_ice_data"], add_trickle=True
)
elif action == self._j.A_TRANSPORT_INFO:
if session["state"] == self._j.STATE_PENDING:
# Session is not yet active; we buffer the arguments to replay them
# when the session becomes active. This makes the frontend's life easier.
log.debug("session is not active yet, buffering transport-info element")
buffer = session.setdefault("XEP-0176_handler_buffer", [])
buffer.append([client, action, session, content_name, transport_elt])
return transport_elt
new_ice_data = self.parse_transport(transport_elt)
restart = self.update_candidates(transport_data, new_ice_data, local=False)
if restart:
log.debug(
f"Peer ICE restart detected on session {session['id']} "
f"[{client.profile}]"
)
self.host.bridge.ice_restart(session["id"], "peer", client.profile)
ice_candidates_new_cb = session.get("ice_candidates_new_cb")
# the content name is used as key, as it is unique in the session (unlike the
# media type, which can be duplicated)
ice_candidates_data = {content_name: new_ice_data}
if ice_candidates_new_cb is None:
self.host.bridge.ice_candidates_new(
session["id"],
data_format.serialise(ice_candidates_data),
client.profile,
)
else:
ice_candidates_new_cb(client, session, ice_candidates_data)
elif action == self._j.A_DESTROY:
pass
else:
log.warning("FIXME: unmanaged action {}".format(action))
return transport_elt
def jingle_terminate(
self,
client: SatXMPPEntity,
action: str,
session: dict,
content_name: str,
reason_elt: domish.Element,
) -> None:
log.debug("ICE-UDP session terminated")
def update_candidates(
self, transport_data: dict, new_ice_data: dict, local: bool
) -> bool:
"""Update ICE candidates when new one are received
@param transport_data: transport_data of the content linked to the candidates
@param new_ice_data: new ICE data, in the same format as returned
by [self.parse_transport]
@param local: True if it's our candidates, False if it's peer ones
@return: True if there is a ICE restart
"""
key = "local_ice_data" if local else "peer_ice_data"
try:
ice_data = transport_data[key]
except KeyError:
log.warning(f"no {key} available")
transport_data[key] = new_ice_data
else:
if (
new_ice_data["ufrag"] != ice_data["ufrag"]
or new_ice_data["pwd"] != ice_data["pwd"]
):
ice_data["ufrag"] = new_ice_data["ufrag"]
ice_data["pwd"] = new_ice_data["pwd"]
ice_data["candidates"] = new_ice_data["candidates"]
return True
return False
async def ice_candidates_add(
self, client: SatXMPPEntity, session_id: str, content_ice_data: dict[str, dict]
) -> None:
"""Called when new ICE candidates are available for a session
@param content_ice_data: a map from content name to ICE data (see
[self.parse_transport]); a media type can also be used as key.
"""
# FIXME: frontends still use media types as key, they need to be updated
session = self._j.get_session(client, session_id)
# FIXME: we use one transport-info IQ per content, as multi-content stanzas are
# rejected by some clients (e.g. Dino)
iqs: list[tuple[dict, str, dict, domish.Element]] = []
for key, new_ice_data in content_ice_data.items():
if key in session["contents"]:
content_names = [key]
else:
# legacy: key is a media type
content_names = [
name
for name, content_data in session["contents"].items()
if content_data["application_data"].get("media") == key
]
if not content_names:
log.warning(f"no content found for {key!r}")
continue
if session["state"] == self._j.STATE_PENDING:
log.debug(f"session not active, buffering")
buffer = session.setdefault("XEP-0176_ice_buffer", {})
for content_name in content_names:
content_buffer = buffer.setdefault(content_name, {})
for ice_key in ["ufrag", "pwd"]:
if ice_key not in content_buffer:
content_buffer[ice_key] = new_ice_data[ice_key]
else:
if content_buffer[ice_key] != new_ice_data[ice_key]:
log.warning(
f"{ice_key} conflict, new value will replace old"
" one\n"
f"buffer={content_buffer[ice_key]!r}\n"
f"new={new_ice_data[ice_key]!r}"
)
content_buffer[ice_key] = new_ice_data[ice_key]
content_buffer.setdefault("candidates", []).extend(
new_ice_data["candidates"]
)
continue
for content_name in content_names:
content_data = session["contents"][content_name]
restart = self.update_candidates(
content_data["transport_data"], new_ice_data, True
)
if restart:
log.debug(
f"Local ICE restart detected on session {session['id']} "
f"[{client.profile}]"
)
self.host.bridge.ice_restart(session["id"], "local", client.profile)
transport_elt = self.build_transport(new_ice_data)
iq_elt, __ = self._j.build_action(
client,
self._j.A_TRANSPORT_INFO,
session,
content_name,
context_elt=transport_elt,
)
iqs.append((new_ice_data, content_name, content_data, iq_elt))
for new_ice_data, content_name, content_data, iq_elt in iqs:
try:
self.host.trigger.point(
"XEP-0176_ice_candidate_send",
client,
session,
new_ice_data,
content_name,
content_data,
iq_elt,
)
await iq_elt.send()
except Exception as e:
log.warning(f"Could not send new ICE candidates: {e}")
@implementer(itx_xmpp.IDisco)
class XEP_0176_handler(XMPPHandler):
def getDiscoInfo(self, requestor, target, nodeIdentifier=""):
return [disco.DiscoFeature(NS_JINGLE_ICE_UDP)]
def getDiscoItems(self, requestor, target, nodeIdentifier=""):
return []