core/homeassistant/components/zeroconf/__init__.py

644 lines
21 KiB
Python

"""Support for exposing Home Assistant via Zeroconf."""
from __future__ import annotations
import asyncio
import contextlib
from contextlib import suppress
from dataclasses import dataclass
from fnmatch import translate
from functools import lru_cache
from ipaddress import IPv4Address, IPv6Address, ip_address
import logging
import re
import socket
import sys
from typing import Any, Final, cast
import voluptuous as vol
from zeroconf import (
BadTypeInNameException,
InterfaceChoice,
IPVersion,
ServiceStateChange,
)
from zeroconf.asyncio import AsyncServiceInfo
from homeassistant import config_entries
from homeassistant.components import network
from homeassistant.components.network import MDNS_TARGET_IP, async_get_source_ip
from homeassistant.components.network.models import Adapter
from homeassistant.const import EVENT_HOMEASSISTANT_STOP, __version__
from homeassistant.core import Event, HomeAssistant, callback
from homeassistant.data_entry_flow import BaseServiceInfo
from homeassistant.helpers import discovery_flow, instance_id
import homeassistant.helpers.config_validation as cv
from homeassistant.helpers.network import NoURLAvailableError, get_url
from homeassistant.helpers.typing import ConfigType
from homeassistant.loader import (
HomeKitDiscoveredIntegration,
async_get_homekit,
async_get_zeroconf,
bind_hass,
)
from homeassistant.setup import async_when_setup_or_start
from .models import HaAsyncServiceBrowser, HaAsyncZeroconf, HaZeroconf
from .usage import install_multiple_zeroconf_catcher
_LOGGER = logging.getLogger(__name__)
DOMAIN = "zeroconf"
ZEROCONF_TYPE = "_home-assistant._tcp.local."
HOMEKIT_TYPES = [
"_hap._tcp.local.",
# Thread based devices
"_hap._udp.local.",
]
# Top level keys we support matching against in properties that are always matched in
# lower case. ex: ZeroconfServiceInfo.name
LOWER_MATCH_ATTRS = {"name"}
CONF_DEFAULT_INTERFACE = "default_interface"
CONF_IPV6 = "ipv6"
DEFAULT_DEFAULT_INTERFACE = True
DEFAULT_IPV6 = True
HOMEKIT_PAIRED_STATUS_FLAG = "sf"
HOMEKIT_MODEL = "md"
# Property key=value has a max length of 255
# so we use 230 to leave space for key=
MAX_PROPERTY_VALUE_LEN = 230
# Dns label max length
MAX_NAME_LEN = 63
ATTR_PROPERTIES: Final = "properties"
# Attributes for ZeroconfServiceInfo[ATTR_PROPERTIES]
ATTR_PROPERTIES_ID: Final = "id"
CONFIG_SCHEMA = vol.Schema(
{
DOMAIN: vol.All(
cv.deprecated(CONF_DEFAULT_INTERFACE),
cv.deprecated(CONF_IPV6),
vol.Schema(
{
vol.Optional(CONF_DEFAULT_INTERFACE): cv.boolean,
vol.Optional(CONF_IPV6, default=DEFAULT_IPV6): cv.boolean,
}
),
)
},
extra=vol.ALLOW_EXTRA,
)
@dataclass(slots=True)
class ZeroconfServiceInfo(BaseServiceInfo):
"""Prepared info from mDNS entries."""
host: str
addresses: list[str]
port: int | None
hostname: str
type: str
name: str
properties: dict[str, Any]
@bind_hass
async def async_get_instance(hass: HomeAssistant) -> HaZeroconf:
"""Zeroconf instance to be shared with other integrations that use it."""
return cast(HaZeroconf, (await _async_get_instance(hass)).zeroconf)
@bind_hass
async def async_get_async_instance(hass: HomeAssistant) -> HaAsyncZeroconf:
"""Zeroconf instance to be shared with other integrations that use it."""
return await _async_get_instance(hass)
async def _async_get_instance(hass: HomeAssistant, **zcargs: Any) -> HaAsyncZeroconf:
if DOMAIN in hass.data:
return cast(HaAsyncZeroconf, hass.data[DOMAIN])
logging.getLogger("zeroconf").setLevel(logging.NOTSET)
zeroconf = HaZeroconf(**zcargs)
aio_zc = HaAsyncZeroconf(zc=zeroconf)
install_multiple_zeroconf_catcher(zeroconf)
async def _async_stop_zeroconf(_event: Event) -> None:
"""Stop Zeroconf."""
await aio_zc.ha_async_close()
hass.bus.async_listen_once(EVENT_HOMEASSISTANT_STOP, _async_stop_zeroconf)
hass.data[DOMAIN] = aio_zc
return aio_zc
@callback
def _async_zc_has_functional_dual_stack() -> bool:
"""Return true for platforms not supporting IP_ADD_MEMBERSHIP on an AF_INET6 socket.
Zeroconf only supports a single listen socket at this time.
"""
return not sys.platform.startswith("freebsd") and not sys.platform.startswith(
"darwin"
)
async def async_setup(hass: HomeAssistant, config: ConfigType) -> bool:
"""Set up Zeroconf and make Home Assistant discoverable."""
zc_args: dict = {"ip_version": IPVersion.V4Only}
adapters = await network.async_get_adapters(hass)
ipv6 = False
if _async_zc_has_functional_dual_stack():
if any(adapter["enabled"] and adapter["ipv6"] for adapter in adapters):
ipv6 = True
zc_args["ip_version"] = IPVersion.All
elif not any(adapter["enabled"] and adapter["ipv4"] for adapter in adapters):
zc_args["ip_version"] = IPVersion.V6Only
ipv6 = True
if not ipv6 and network.async_only_default_interface_enabled(adapters):
zc_args["interfaces"] = InterfaceChoice.Default
else:
zc_args["interfaces"] = [
str(source_ip)
for source_ip in await network.async_get_enabled_source_ips(hass)
if not source_ip.is_loopback
and not (isinstance(source_ip, IPv6Address) and source_ip.is_global)
and not (
isinstance(source_ip, IPv6Address)
and zc_args["ip_version"] == IPVersion.V4Only
)
and not (
isinstance(source_ip, IPv4Address)
and zc_args["ip_version"] == IPVersion.V6Only
)
]
aio_zc = await _async_get_instance(hass, **zc_args)
zeroconf = cast(HaZeroconf, aio_zc.zeroconf)
zeroconf_types, homekit_models = await asyncio.gather(
async_get_zeroconf(hass), async_get_homekit(hass)
)
discovery = ZeroconfDiscovery(hass, zeroconf, zeroconf_types, homekit_models, ipv6)
await discovery.async_setup()
async def _async_zeroconf_hass_start(hass: HomeAssistant, comp: str) -> None:
"""Expose Home Assistant on zeroconf when it starts.
Wait till started or otherwise HTTP is not up and running.
"""
uuid = await instance_id.async_get(hass)
await _async_register_hass_zc_service(hass, aio_zc, uuid)
async def _async_zeroconf_hass_stop(_event: Event) -> None:
await discovery.async_stop()
hass.bus.async_listen_once(EVENT_HOMEASSISTANT_STOP, _async_zeroconf_hass_stop)
async_when_setup_or_start(hass, "frontend", _async_zeroconf_hass_start)
return True
def _get_announced_addresses(
adapters: list[Adapter],
first_ip: bytes | None = None,
) -> list[bytes]:
"""Return a list of IP addresses to announce via zeroconf.
If first_ip is not None, it will be the first address in the list.
"""
addresses = {
addr.packed
for addr in [
ip_address(ip["address"])
for adapter in adapters
if adapter["enabled"]
for ip in cast(list, adapter["ipv6"]) + cast(list, adapter["ipv4"])
]
if not (addr.is_unspecified or addr.is_loopback)
}
if first_ip:
address_list = [first_ip]
address_list.extend(addresses - set({first_ip}))
else:
address_list = list(addresses)
return address_list
def _filter_disallowed_characters(name: str) -> str:
"""Filter disallowed characters from a string.
. is a reversed character for zeroconf.
"""
return name.replace(".", " ")
async def _async_register_hass_zc_service(
hass: HomeAssistant, aio_zc: HaAsyncZeroconf, uuid: str
) -> None:
# Get instance UUID
valid_location_name = _truncate_location_name_to_valid(
_filter_disallowed_characters(hass.config.location_name or "Home")
)
params = {
"location_name": valid_location_name,
"uuid": uuid,
"version": __version__,
"external_url": "",
"internal_url": "",
# Old base URL, for backward compatibility
"base_url": "",
# Always needs authentication
"requires_api_password": True,
}
# Get instance URL's
with suppress(NoURLAvailableError):
params["external_url"] = get_url(hass, allow_internal=False)
with suppress(NoURLAvailableError):
params["internal_url"] = get_url(hass, allow_external=False)
# Set old base URL based on external or internal
params["base_url"] = params["external_url"] or params["internal_url"]
adapters = await network.async_get_adapters(hass)
# Puts the default IPv4 address first in the list to preserve compatibility,
# because some mDNS implementations ignores anything but the first announced
# address.
host_ip = await async_get_source_ip(hass, target_ip=MDNS_TARGET_IP)
host_ip_pton = None
if host_ip:
host_ip_pton = socket.inet_pton(socket.AF_INET, host_ip)
address_list = _get_announced_addresses(adapters, host_ip_pton)
_suppress_invalid_properties(params)
info = AsyncServiceInfo(
ZEROCONF_TYPE,
name=f"{valid_location_name}.{ZEROCONF_TYPE}",
server=f"{uuid}.local.",
addresses=address_list,
port=hass.http.server_port,
properties=params,
)
_LOGGER.info("Starting Zeroconf broadcast")
await aio_zc.async_register_service(info, allow_name_change=True)
def _match_against_data(
matcher: dict[str, str | dict[str, str]], match_data: dict[str, str]
) -> bool:
"""Check a matcher to ensure all values in match_data match."""
for key in LOWER_MATCH_ATTRS:
if key not in matcher:
continue
if key not in match_data:
return False
match_val = matcher[key]
assert isinstance(match_val, str)
if not _memorized_fnmatch(match_data[key], match_val):
return False
return True
def _match_against_props(matcher: dict[str, str], props: dict[str, str]) -> bool:
"""Check a matcher to ensure all values in props."""
return not any(
key
for key in matcher
if key not in props or not _memorized_fnmatch(props[key].lower(), matcher[key])
)
def is_homekit_paired(props: dict[str, Any]) -> bool:
"""Check properties to see if a device is homekit paired."""
if HOMEKIT_PAIRED_STATUS_FLAG not in props:
return False
with contextlib.suppress(ValueError):
# 0 means paired and not discoverable by iOS clients)
return int(props[HOMEKIT_PAIRED_STATUS_FLAG]) == 0
# If we cannot tell, we assume its not paired
return False
class ZeroconfDiscovery:
"""Discovery via zeroconf."""
def __init__(
self,
hass: HomeAssistant,
zeroconf: HaZeroconf,
zeroconf_types: dict[str, list[dict[str, str | dict[str, str]]]],
homekit_models: dict[str, HomeKitDiscoveredIntegration],
ipv6: bool,
) -> None:
"""Init discovery."""
self.hass = hass
self.zeroconf = zeroconf
self.zeroconf_types = zeroconf_types
self.homekit_models = homekit_models
self.ipv6 = ipv6
self.async_service_browser: HaAsyncServiceBrowser | None = None
async def async_setup(self) -> None:
"""Start discovery."""
types = list(self.zeroconf_types)
# We want to make sure we know about other HomeAssistant
# instances as soon as possible to avoid name conflicts
# so we always browse for ZEROCONF_TYPE
for hk_type in (ZEROCONF_TYPE, *HOMEKIT_TYPES):
if hk_type not in self.zeroconf_types:
types.append(hk_type)
_LOGGER.debug("Starting Zeroconf browser for: %s", types)
self.async_service_browser = HaAsyncServiceBrowser(
self.ipv6, self.zeroconf, types, handlers=[self.async_service_update]
)
async def async_stop(self) -> None:
"""Cancel the service browser and stop processing the queue."""
if self.async_service_browser:
await self.async_service_browser.async_cancel()
def _async_dismiss_discoveries(self, name: str) -> None:
"""Dismiss all discoveries for the given name."""
for flow in self.hass.config_entries.flow.async_progress_by_init_data_type(
ZeroconfServiceInfo,
lambda service_info: bool(service_info.name == name),
):
self.hass.config_entries.flow.async_abort(flow["flow_id"])
@callback
def async_service_update(
self,
zeroconf: HaZeroconf,
service_type: str,
name: str,
state_change: ServiceStateChange,
) -> None:
"""Service state changed."""
_LOGGER.debug(
"service_update: type=%s name=%s state_change=%s",
service_type,
name,
state_change,
)
if state_change == ServiceStateChange.Removed:
self._async_dismiss_discoveries(name)
return
try:
async_service_info = AsyncServiceInfo(service_type, name)
except BadTypeInNameException as ex:
# Some devices broadcast a name that is not a valid DNS name
# This is a bug in the device firmware and we should ignore it
_LOGGER.debug("Bad name in zeroconf record: %s: %s", name, ex)
return
if async_service_info.load_from_cache(zeroconf):
self._async_process_service_update(async_service_info, service_type, name)
else:
self.hass.async_create_task(
self._async_lookup_and_process_service_update(
zeroconf, async_service_info, service_type, name
)
)
async def _async_lookup_and_process_service_update(
self,
zeroconf: HaZeroconf,
async_service_info: AsyncServiceInfo,
service_type: str,
name: str,
) -> None:
"""Update and process a zeroconf update."""
await async_service_info.async_request(zeroconf, 3000)
self._async_process_service_update(async_service_info, service_type, name)
@callback
def _async_process_service_update(
self, async_service_info: AsyncServiceInfo, service_type: str, name: str
) -> None:
"""Process a zeroconf update."""
info = info_from_service(async_service_info)
if not info:
# Prevent the browser thread from collapsing
_LOGGER.debug("Failed to get addresses for device %s", name)
return
_LOGGER.debug("Discovered new device %s %s", name, info)
props: dict[str, str] = info.properties
domain = None
# If we can handle it as a HomeKit discovery, we do that here.
if service_type in HOMEKIT_TYPES and (
homekit_model := async_get_homekit_discovery_domain(
self.homekit_models, props
)
):
domain = homekit_model.domain
discovery_flow.async_create_flow(
self.hass,
homekit_model.domain,
{"source": config_entries.SOURCE_HOMEKIT},
info,
)
# Continue on here as homekit_controller
# still needs to get updates on devices
# so it can see when the 'c#' field is updated.
#
# We only send updates to homekit_controller
# if the device is already paired in order to avoid
# offering a second discovery for the same device
if not is_homekit_paired(props) and not homekit_model.always_discover:
# If the device is paired with HomeKit we must send on
# the update to homekit_controller so it can see when
# the 'c#' field is updated. This is used to detect
# when the device has been reset or updated.
#
# If the device is not paired and we should not always
# discover it, we can stop here.
return
match_data: dict[str, str] = {}
for key in LOWER_MATCH_ATTRS:
attr_value: str = getattr(info, key)
match_data[key] = attr_value.lower()
# Not all homekit types are currently used for discovery
# so not all service type exist in zeroconf_types
for matcher in self.zeroconf_types.get(service_type, []):
if len(matcher) > 1:
if not _match_against_data(matcher, match_data):
continue
if ATTR_PROPERTIES in matcher:
matcher_props = matcher[ATTR_PROPERTIES]
assert isinstance(matcher_props, dict)
if not _match_against_props(matcher_props, props):
continue
matcher_domain = matcher["domain"]
assert isinstance(matcher_domain, str)
context = {
"source": config_entries.SOURCE_ZEROCONF,
}
if domain:
# Domain of integration that offers alternative API to handle
# this device.
context["alternative_domain"] = domain
discovery_flow.async_create_flow(
self.hass,
matcher_domain,
context,
info,
)
def async_get_homekit_discovery_domain(
homekit_models: dict[str, HomeKitDiscoveredIntegration], props: dict[str, Any]
) -> HomeKitDiscoveredIntegration | None:
"""Handle a HomeKit discovery.
Return the domain to forward the discovery data to
"""
model = None
for key in props:
if key.lower() == HOMEKIT_MODEL:
model = props[key]
break
if model is None:
return None
for test_model in homekit_models:
if (
model != test_model
and not model.startswith((f"{test_model} ", f"{test_model}-"))
and not _memorized_fnmatch(model, test_model)
):
continue
return homekit_models[test_model]
return None
def info_from_service(service: AsyncServiceInfo) -> ZeroconfServiceInfo | None:
"""Return prepared info from mDNS entries."""
properties: dict[str, Any] = {"_raw": {}}
for key, value in service.properties.items():
# See https://ietf.org/rfc/rfc6763.html#section-6.4 and
# https://ietf.org/rfc/rfc6763.html#section-6.5 for expected encodings
# for property keys and values
try:
key = key.decode("ascii")
except UnicodeDecodeError:
_LOGGER.debug(
"Ignoring invalid key provided by [%s]: %s", service.name, key
)
continue
properties["_raw"][key] = value
with suppress(UnicodeDecodeError):
if isinstance(value, bytes):
properties[key] = value.decode("utf-8")
if not (ip_addresses := service.ip_addresses_by_version(IPVersion.All)):
return None
host: str | None = None
for ip_addr in ip_addresses:
if not ip_addr.is_link_local and not ip_addr.is_unspecified:
host = str(ip_addr)
break
if not host:
return None
assert service.server is not None, "server cannot be none if there are addresses"
return ZeroconfServiceInfo(
host=host,
addresses=[str(ip_addr) for ip_addr in ip_addresses],
port=service.port,
hostname=service.server,
type=service.type,
name=service.name,
properties=properties,
)
def _suppress_invalid_properties(properties: dict) -> None:
"""Suppress any properties that will cause zeroconf to fail to startup."""
for prop, prop_value in properties.items():
if not isinstance(prop_value, str):
continue
if len(prop_value.encode("utf-8")) > MAX_PROPERTY_VALUE_LEN:
_LOGGER.error(
(
"The property '%s' was suppressed because it is longer than the"
" maximum length of %d bytes: %s"
),
prop,
MAX_PROPERTY_VALUE_LEN,
prop_value,
)
properties[prop] = ""
def _truncate_location_name_to_valid(location_name: str) -> str:
"""Truncate or return the location name usable for zeroconf."""
if len(location_name.encode("utf-8")) < MAX_NAME_LEN:
return location_name
_LOGGER.warning(
(
"The location name was truncated because it is longer than the maximum"
" length of %d bytes: %s"
),
MAX_NAME_LEN,
location_name,
)
return location_name.encode("utf-8")[:MAX_NAME_LEN].decode("utf-8", "ignore")
@lru_cache(maxsize=4096, typed=True)
def _compile_fnmatch(pattern: str) -> re.Pattern:
"""Compile a fnmatch pattern."""
return re.compile(translate(pattern))
@lru_cache(maxsize=1024, typed=True)
def _memorized_fnmatch(name: str, pattern: str) -> bool:
"""Memorized version of fnmatch that has a larger lru_cache.
The default version of fnmatch only has a lru_cache of 256 entries.
With many devices we quickly reach that limit and end up compiling
the same pattern over and over again.
Zeroconf has its own memorized fnmatch with its own lru_cache
since the data is going to be relatively the same
since the devices will not change frequently
"""
return bool(_compile_fnmatch(pattern).match(name))