#!/usr/bin/env python3
# Libervia plugin
# Copyright (C) 2009-2023 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 Dict, List, Optional, Union
from twisted.words.protocols.jabber.xmlstream import XMPPHandler
from twisted.words.xish import domish
from wokkel import disco, iwokkel
from zope.interface import implementer
from sat.core import exceptions
from sat.core.constants import Const as C
from sat.core.i18n import _
from sat.core.log import getLogger
log = getLogger(__name__)
NS_JINGLE_RTP_HDREXT = "urn:xmpp:jingle:apps:rtp:rtp-hdrext:0"
PLUGIN_INFO = {
C.PI_NAME: "Jingle RTP Header Extensions Negotiation",
C.PI_IMPORT_NAME: "XEP-0294",
C.PI_TYPE: "XEP",
C.PI_MODES: C.PLUG_MODE_BOTH,
C.PI_PROTOCOLS: ["XEP-0294"],
C.PI_DEPENDENCIES: ["XEP-0167"],
C.PI_RECOMMENDATIONS: [],
C.PI_MAIN: "XEP_0294",
C.PI_HANDLER: "yes",
C.PI_DESCRIPTION: _("""Jingle RTP Header Extensions Negotiation"""),
}
class XEP_0294:
def __init__(self, host):
log.info(f"plugin {PLUGIN_INFO[C.PI_NAME]!r} initialization")
host.trigger.add("XEP-0167_parse_sdp_a", self._parse_sdp_a_trigger)
host.trigger.add(
"XEP-0167_generate_sdp_content", self._generate_sdp_content_trigger
)
host.trigger.add("XEP-0167_parse_description", self._parse_description_trigger)
host.trigger.add("XEP-0167_build_description", self._build_description_trigger)
def get_handler(self, client):
return XEP_0294_handler()
def _parse_extmap(self, parts: List[str], application_data: dict) -> None:
"""Parse an individual extmap line and fill application_data accordingly"""
if "/" in parts[0]:
id_, direction = parts[0].split("/", 1)
else:
id_ = parts[0]
direction = None
uri = parts[1]
attributes = parts[2:]
if direction in (None, "sendrecv"):
senders = "both"
elif direction == "sendonly":
senders = "initiator"
elif direction == "recvonly":
senders = "responder"
elif direction == "inactive":
senders = "none"
else:
log.warning(f"invalid direction for extmap: {direction}")
senders = "sendrecv"
rtp_hdr_ext_data: Dict[str, Union[str, dict]] = {
"id": id_,
"uri": uri,
"senders": senders,
}
if attributes:
parameters = {}
for attribute in attributes:
name, *value = attribute.split("=", 1)
parameters[name] = value[0] if value else None
rtp_hdr_ext_data["parameters"] = parameters
application_data.setdefault("rtp-hdrext", {})[id_] = rtp_hdr_ext_data
def _parse_sdp_a_trigger(
self,
attribute: str,
parts: List[str],
call_data: dict,
metadata: dict,
media_type: str,
application_data: Optional[dict],
transport_data: dict,
) -> None:
"""Parse "extmap" and "extmap-allow-mixed" attributes"""
if attribute == "extmap":
if application_data is None:
call_data.setdefault("_extmaps", []).append(parts)
else:
self._parse_extmap(parts, application_data)
elif attribute == "extmap-allow-mixed":
if application_data is None:
call_data["_extmap-allow-mixed"] = True
else:
application_data["extmap-allow-mixed"] = True
elif (
application_data is not None
and "_extmaps" in call_data
and "rtp-hdrext" not in application_data
):
extmaps = call_data.pop("_extmaps")
for parts in extmaps:
self._parse_extmap(parts, application_data)
elif (
application_data is not None
and "_extmap-allow-mixed" in call_data
and "extmap-allow-mixed" not in application_data
):
value = call_data.pop("_extmap-allow-mixed")
application_data["extmap-allow-mixed"] = value
def _generate_sdp_content_trigger(
self,
session: dict,
local: bool,
idx: int,
content_data: dict,
sdp_lines: List[str],
application_data: dict,
app_data_key: str,
media_data: dict,
media: str,
) -> None:
"""Generate "extmap" and "extmap-allow-mixed" attributes"""
rtp_hdrext_dict = media_data.get("rtp-hdrext", {})
for id_, ext_data in rtp_hdrext_dict.items():
senders = ext_data.get("senders")
if senders in (None, "both"):
direction = "sendrecv"
elif senders == "initiator":
direction = "sendonly"
elif senders == "responder":
direction = "recvonly"
elif senders == "none":
direction = "inactive"
else:
raise exceptions.InternalError(
f"Invalid senders value for extmap: {ext_data.get('senders')}"
)
parameters_str = ""
if "parameters" in ext_data:
parameters_str = " " + " ".join(
f"{k}={v}" if v is not None else f"{k}"
for k, v in ext_data["parameters"].items()
)
sdp_lines.append(
f"a=extmap:{id_}/{direction} {ext_data['uri']}{parameters_str}"
)
if media_data.get("extmap-allow-mixed", False):
sdp_lines.append("a=extmap-allow-mixed")
def _parse_description_trigger(
self, desc_elt: domish.Element, media_data: dict
) -> None:
"""Parse the and elements"""
for rtp_hdrext_elt in desc_elt.elements(NS_JINGLE_RTP_HDREXT, "rtp-hdrext"):
id_ = rtp_hdrext_elt["id"]
uri = rtp_hdrext_elt["uri"]
senders = rtp_hdrext_elt.getAttribute("senders", "both")
# FIXME: workaround for Movim bug https://github.com/movim/movim/issues/1212
if senders in ("sendonly", "recvonly", "sendrecv", "inactive"):
log.warning("Movim bug workaround for wrong extmap value")
if senders == "sendonly":
senders = "initiator"
elif senders == "recvonly":
senders = "responder"
elif senders == "sendrecv":
senders = "both"
else:
senders = "none"
media_data.setdefault("rtp-hdrext", {})[id_] = {
"id": id_,
"uri": uri,
"senders": senders,
}
parameters = {}
for param_elt in rtp_hdrext_elt.elements(NS_JINGLE_RTP_HDREXT, "parameter"):
try:
parameters[param_elt["name"]] = param_elt.getAttribute("value")
except KeyError:
log.warning(f"invalid parameters (missing name): {param_elt.toXml()}")
if parameters:
media_data["rtp-hdrext"][id_]["parameters"] = parameters
try:
next(desc_elt.elements(NS_JINGLE_RTP_HDREXT, "extmap-allow-mixed"))
except StopIteration:
pass
else:
media_data["extmap-allow-mixed"] = True
def _build_description_trigger(
self, desc_elt: domish.Element, media_data: dict, session: dict
) -> None:
"""Build the and elements if possible"""
for id_, hdrext_data in media_data.get("rtp-hdrext", {}).items():
rtp_hdrext_elt = desc_elt.addElement((NS_JINGLE_RTP_HDREXT, "rtp-hdrext"))
rtp_hdrext_elt["id"] = id_
rtp_hdrext_elt["uri"] = hdrext_data["uri"]
senders = hdrext_data.get("senders", "both")
if senders != "both":
# we must not set "both" senders otherwise calls will fail with Movim due
# to https://github.com/movim/movim/issues/1213
rtp_hdrext_elt["senders"] = senders
for name, value in hdrext_data.get("parameters", {}).items():
param_elt = rtp_hdrext_elt.addElement((NS_JINGLE_RTP_HDREXT, "parameter"))
param_elt["name"] = name
if value is not None:
param_elt["value"] = value
if media_data.get("extmap-allow-mixed", False):
desc_elt.addElement((NS_JINGLE_RTP_HDREXT, "extmap-allow-mixed"))
@implementer(iwokkel.IDisco)
class XEP_0294_handler(XMPPHandler):
def getDiscoInfo(self, requestor, target, nodeIdentifier=""):
return [disco.DiscoFeature(NS_JINGLE_RTP_HDREXT)]
def getDiscoItems(self, requestor, target, nodeIdentifier=""):
return []