"""Discovery module for TP-Link Smart Home devices."""
from __future__ import annotations
import asyncio
import binascii
import ipaddress
import logging
import socket
from typing import Awaitable, Callable, Dict, Optional, Type, cast
# When support for cpython older than 3.11 is dropped
# async_timeout can be replaced with asyncio.timeout
from async_timeout import timeout as asyncio_timeout
try:
from pydantic.v1 import BaseModel, ValidationError # pragma: no cover
except ImportError:
from pydantic import BaseModel, ValidationError # pragma: no cover
from kasa import Device
from kasa.credentials import Credentials
from kasa.device_factory import (
get_device_class_from_family,
get_device_class_from_sys_info,
get_protocol,
)
from kasa.deviceconfig import ConnectionType, DeviceConfig, EncryptType
from kasa.exceptions import (
KasaException,
TimeoutError,
UnsupportedDeviceError,
)
from kasa.iot.iotdevice import IotDevice
from kasa.json import dumps as json_dumps
from kasa.json import loads as json_loads
from kasa.xortransport import XorEncryption
_LOGGER = logging.getLogger(__name__)
OnDiscoveredCallable = Callable[[Device], Awaitable[None]]
OnUnsupportedCallable = Callable[[UnsupportedDeviceError], Awaitable[None]]
DeviceDict = Dict[str, Device]
class _DiscoverProtocol(asyncio.DatagramProtocol):
"""Implementation of the discovery protocol handler.
This is internal class, use :func:`Discover.discover`: instead.
"""
DISCOVERY_START_TIMEOUT = 1
discovered_devices: DeviceDict
def __init__(
self,
*,
on_discovered: OnDiscoveredCallable | None = None,
target: str = "255.255.255.255",
discovery_packets: int = 3,
discovery_timeout: int = 5,
interface: str | None = None,
on_unsupported: OnUnsupportedCallable | None = None,
port: int | None = None,
credentials: Credentials | None = None,
timeout: int | None = None,
) -> None:
self.transport = None
self.discovery_packets = discovery_packets
self.interface = interface
self.on_discovered = on_discovered
self.port = port
self.discovery_port = port or Discover.DISCOVERY_PORT
self.target = target
self.target_1 = (target, self.discovery_port)
self.target_2 = (target, Discover.DISCOVERY_PORT_2)
self.discovered_devices = {}
self.unsupported_device_exceptions: dict = {}
self.invalid_device_exceptions: dict = {}
self.on_unsupported = on_unsupported
self.credentials = credentials
self.timeout = timeout
self.discovery_timeout = discovery_timeout
self.seen_hosts: set[str] = set()
self.discover_task: asyncio.Task | None = None
self.callback_tasks: list[asyncio.Task] = []
self.target_discovered: bool = False
self._started_event = asyncio.Event()
def _run_callback_task(self, coro):
task = asyncio.create_task(coro)
self.callback_tasks.append(task)
async def wait_for_discovery_to_complete(self):
"""Wait for the discovery task to complete."""
# Give some time for connection_made event to be received
async with asyncio_timeout(self.DISCOVERY_START_TIMEOUT):
await self._started_event.wait()
try:
await self.discover_task
except asyncio.CancelledError:
# if target_discovered then cancel was called internally
if not self.target_discovered:
raise
# Wait for any pending callbacks to complete
await asyncio.gather(*self.callback_tasks)
def connection_made(self, transport) -> None:
"""Set socket options for broadcasting."""
self.transport = transport
sock = transport.get_extra_info("socket")
sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
try:
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
except OSError as ex: # WSL does not support SO_REUSEADDR, see #246
_LOGGER.debug("Unable to set SO_REUSEADDR: %s", ex)
if self.interface is not None:
sock.setsockopt(
socket.SOL_SOCKET, socket.SO_BINDTODEVICE, self.interface.encode()
)
self.discover_task = asyncio.create_task(self.do_discover())
self._started_event.set()
async def do_discover(self) -> None:
"""Send number of discovery datagrams."""
req = json_dumps(Discover.DISCOVERY_QUERY)
_LOGGER.debug("[DISCOVERY] %s >> %s", self.target, Discover.DISCOVERY_QUERY)
encrypted_req = XorEncryption.encrypt(req)
sleep_between_packets = self.discovery_timeout / self.discovery_packets
for _ in range(self.discovery_packets):
if self.target in self.seen_hosts: # Stop sending for discover_single
break
self.transport.sendto(encrypted_req[4:], self.target_1) # type: ignore
self.transport.sendto(Discover.DISCOVERY_QUERY_2, self.target_2) # type: ignore
await asyncio.sleep(sleep_between_packets)
def datagram_received(self, data, addr) -> None:
"""Handle discovery responses."""
ip, port = addr
# Prevent multiple entries due multiple broadcasts
if ip in self.seen_hosts:
return
self.seen_hosts.add(ip)
device: Device | None = None
config = DeviceConfig(host=ip, port_override=self.port)
if self.credentials:
config.credentials = self.credentials
if self.timeout:
config.timeout = self.timeout
try:
if port == self.discovery_port:
device = Discover._get_device_instance_legacy(data, config)
elif port == Discover.DISCOVERY_PORT_2:
config.uses_http = True
device = Discover._get_device_instance(data, config)
else:
return
except UnsupportedDeviceError as udex:
_LOGGER.debug("Unsupported device found at %s << %s", ip, udex)
self.unsupported_device_exceptions[ip] = udex
if self.on_unsupported is not None:
self._run_callback_task(self.on_unsupported(udex))
self._handle_discovered_event()
return
except KasaException as ex:
_LOGGER.debug(f"[DISCOVERY] Unable to find device type for {ip}: {ex}")
self.invalid_device_exceptions[ip] = ex
self._handle_discovered_event()
return
self.discovered_devices[ip] = device
if self.on_discovered is not None:
self._run_callback_task(self.on_discovered(device))
self._handle_discovered_event()
def _handle_discovered_event(self):
"""If target is in seen_hosts cancel discover_task."""
if self.target in self.seen_hosts:
self.target_discovered = True
if self.discover_task:
self.discover_task.cancel()
def error_received(self, ex):
"""Handle asyncio.Protocol errors."""
_LOGGER.error("Got error: %s", ex)
def connection_lost(self, ex): # pragma: no cover
"""Cancel the discover task if running."""
if self.discover_task:
self.discover_task.cancel()
[docs]class Discover:
"""Discover TPLink Smart Home devices.
The main entry point for this library is :func:`Discover.discover()`,
which returns a dictionary of the found devices. The key is the IP address
of the device and the value contains ready-to-use, SmartDevice-derived
device object.
:func:`discover_single()` can be used to initialize a single device given its
IP address. If the :class:`DeviceConfig` of the device is already known,
you can initialize the corresponding device class directly without discovery.
The protocol uses UDP broadcast datagrams on port 9999 and 20002 for discovery.
Legacy devices support discovery on port 9999 and newer devices on 20002.
Newer devices that respond on port 20002 will most likely require TP-Link cloud
credentials to be passed if queries or updates are to be performed on the returned
devices.
Examples:
Discovery returns a list of discovered devices:
>>> import asyncio
>>> found_devices = asyncio.run(Discover.discover())
>>> [dev.alias for dev in found_devices]
['TP-LINK_Power Strip_CF69']
Discovery can also be targeted to a specific broadcast address instead of
the default 255.255.255.255:
>>> asyncio.run(Discover.discover(target="192.168.8.255"))
It is also possible to pass a coroutine to be executed for each found device:
>>> async def print_alias(dev):
>>> print(f"Discovered {dev.alias}")
>>> devices = asyncio.run(Discover.discover(on_discovered=print_alias))
"""
DISCOVERY_PORT = 9999
DISCOVERY_QUERY = {
"system": {"get_sysinfo": None},
}
DISCOVERY_PORT_2 = 20002
DISCOVERY_QUERY_2 = binascii.unhexlify("020000010000000000000000463cb5d3")
[docs] @staticmethod
async def discover(
*,
target="255.255.255.255",
on_discovered=None,
discovery_timeout=5,
discovery_packets=3,
interface=None,
on_unsupported=None,
credentials=None,
port=None,
timeout=None,
) -> DeviceDict:
"""Discover supported devices.
Sends discovery message to 255.255.255.255:9999 and
255.255.255.255:20002 in order
to detect available supported devices in the local network,
and waits for given timeout for answers from devices.
If you have multiple interfaces,
you can use *target* parameter to specify the network for discovery.
If given, `on_discovered` coroutine will get awaited with
a :class:`SmartDevice`-derived object as parameter.
The results of the discovery are returned as a dict of
:class:`SmartDevice`-derived objects keyed with IP addresses.
The devices are already initialized and all but emeter-related properties
can be accessed directly.
:param target: The target address where to send the broadcast discovery
queries if multi-homing (e.g. 192.168.xxx.255).
:param on_discovered: coroutine to execute on discovery
:param discovery_timeout: Seconds to wait for responses, defaults to 5
:param discovery_packets: Number of discovery packets to broadcast
:param interface: Bind to specific interface
:param on_unsupported: Optional callback when unsupported devices are discovered
:param credentials: Credentials for devices requiring authentication
:param port: Override the discovery port for devices listening on 9999
:param timeout: Query timeout in seconds for devices returned by discovery
:return: dictionary with discovered devices
"""
loop = asyncio.get_event_loop()
transport, protocol = await loop.create_datagram_endpoint(
lambda: _DiscoverProtocol(
target=target,
on_discovered=on_discovered,
discovery_packets=discovery_packets,
interface=interface,
on_unsupported=on_unsupported,
credentials=credentials,
timeout=timeout,
discovery_timeout=discovery_timeout,
port=port,
),
local_addr=("0.0.0.0", 0), # noqa: S104
)
protocol = cast(_DiscoverProtocol, protocol)
try:
_LOGGER.debug("Waiting %s seconds for responses...", discovery_timeout)
await protocol.wait_for_discovery_to_complete()
except KasaException as ex:
for device in protocol.discovered_devices.values():
await device.protocol.close()
raise ex
finally:
transport.close()
_LOGGER.debug("Discovered %s devices", len(protocol.discovered_devices))
return protocol.discovered_devices
[docs] @staticmethod
async def discover_single(
host: str,
*,
discovery_timeout: int = 5,
port: int | None = None,
timeout: int | None = None,
credentials: Credentials | None = None,
) -> Device:
"""Discover a single device by the given IP address.
It is generally preferred to avoid :func:`discover_single()` and
use :meth:`SmartDevice.connect()` instead as it should perform better when
the WiFi network is congested or the device is not responding
to discovery requests.
:param host: Hostname of device to query
:param discovery_timeout: Timeout in seconds for discovery
:param port: Optionally set a different port for legacy devices using port 9999
:param timeout: Timeout in seconds device for devices queries
:param credentials: Credentials for devices that require authentication
:rtype: SmartDevice
:return: Object for querying/controlling found device.
"""
loop = asyncio.get_event_loop()
try:
ipaddress.ip_address(host)
ip = host
except ValueError:
try:
adrrinfo = await loop.getaddrinfo(
host,
0,
type=socket.SOCK_DGRAM,
family=socket.AF_INET,
)
# getaddrinfo returns a list of 5 tuples with the following structure:
# (family, type, proto, canonname, sockaddr)
# where sockaddr is 2 tuple (ip, port).
# hence [0][4][0] is a stable array access because if no socket
# address matches the host for SOCK_DGRAM AF_INET the gaierror
# would be raised.
# https://docs.python.org/3/library/socket.html#socket.getaddrinfo
ip = adrrinfo[0][4][0]
except socket.gaierror as gex:
raise KasaException(f"Could not resolve hostname {host}") from gex
transport, protocol = await loop.create_datagram_endpoint(
lambda: _DiscoverProtocol(
target=ip,
port=port,
credentials=credentials,
timeout=timeout,
discovery_timeout=discovery_timeout,
),
local_addr=("0.0.0.0", 0), # noqa: S104
)
protocol = cast(_DiscoverProtocol, protocol)
try:
_LOGGER.debug(
"Waiting a total of %s seconds for responses...", discovery_timeout
)
await protocol.wait_for_discovery_to_complete()
finally:
transport.close()
if ip in protocol.discovered_devices:
dev = protocol.discovered_devices[ip]
dev.host = host
return dev
elif ip in protocol.unsupported_device_exceptions:
raise protocol.unsupported_device_exceptions[ip]
elif ip in protocol.invalid_device_exceptions:
raise protocol.invalid_device_exceptions[ip]
else:
raise TimeoutError(f"Timed out getting discovery response for {host}")
@staticmethod
def _get_device_class(info: dict) -> type[Device]:
"""Find SmartDevice subclass for device described by passed data."""
if "result" in info:
discovery_result = DiscoveryResult(**info["result"])
dev_class = get_device_class_from_family(discovery_result.device_type)
if not dev_class:
raise UnsupportedDeviceError(
"Unknown device type: %s" % discovery_result.device_type,
discovery_result=info,
)
return dev_class
else:
return get_device_class_from_sys_info(info)
@staticmethod
def _get_device_instance_legacy(data: bytes, config: DeviceConfig) -> IotDevice:
"""Get SmartDevice from legacy 9999 response."""
try:
info = json_loads(XorEncryption.decrypt(data))
except Exception as ex:
raise KasaException(
f"Unable to read response from device: {config.host}: {ex}"
) from ex
_LOGGER.debug("[DISCOVERY] %s << %s", config.host, info)
device_class = cast(Type[IotDevice], Discover._get_device_class(info))
device = device_class(config.host, config=config)
sys_info = info["system"]["get_sysinfo"]
if device_type := sys_info.get("mic_type", sys_info.get("type")):
config.connection_type = ConnectionType.from_values(
device_family=device_type, encryption_type=EncryptType.Xor.value
)
device.protocol = get_protocol(config) # type: ignore[assignment]
device.update_from_discover_info(info)
return device
@staticmethod
def _get_device_instance(
data: bytes,
config: DeviceConfig,
) -> Device:
"""Get SmartDevice from the new 20002 response."""
try:
info = json_loads(data[16:])
except Exception as ex:
_LOGGER.debug("Got invalid response from device %s: %s", config.host, data)
raise KasaException(
f"Unable to read response from device: {config.host}: {ex}"
) from ex
try:
discovery_result = DiscoveryResult(**info["result"])
except ValidationError as ex:
_LOGGER.debug(
"Unable to parse discovery from device %s: %s", config.host, info
)
raise UnsupportedDeviceError(
f"Unable to parse discovery from device: {config.host}: {ex}"
) from ex
type_ = discovery_result.device_type
try:
config.connection_type = ConnectionType.from_values(
type_,
discovery_result.mgt_encrypt_schm.encrypt_type,
discovery_result.mgt_encrypt_schm.lv,
)
except KasaException as ex:
raise UnsupportedDeviceError(
f"Unsupported device {config.host} of type {type_} "
+ f"with encrypt_type {discovery_result.mgt_encrypt_schm.encrypt_type}",
discovery_result=discovery_result.get_dict(),
) from ex
if (device_class := get_device_class_from_family(type_)) is None:
_LOGGER.warning("Got unsupported device type: %s", type_)
raise UnsupportedDeviceError(
f"Unsupported device {config.host} of type {type_}: {info}",
discovery_result=discovery_result.get_dict(),
)
if (protocol := get_protocol(config)) is None:
_LOGGER.warning(
"Got unsupported connection type: %s", config.connection_type.to_dict()
)
raise UnsupportedDeviceError(
f"Unsupported encryption scheme {config.host} of "
+ f"type {config.connection_type.to_dict()}: {info}",
discovery_result=discovery_result.get_dict(),
)
_LOGGER.debug("[DISCOVERY] %s << %s", config.host, info)
device = device_class(config.host, protocol=protocol)
di = discovery_result.get_dict()
di["model"], _, _ = discovery_result.device_model.partition("(")
device.update_from_discover_info(di)
return device
class EncryptionScheme(BaseModel):
"""Base model for encryption scheme of discovery result."""
is_support_https: bool
encrypt_type: str
http_port: int
lv: Optional[int] = None # noqa: UP007
class DiscoveryResult(BaseModel):
"""Base model for discovery result."""
device_type: str
device_model: str
ip: str
mac: str
mgt_encrypt_schm: EncryptionScheme
device_id: str
hw_ver: Optional[str] = None # noqa: UP007
owner: Optional[str] = None # noqa: UP007
is_support_iot_cloud: Optional[bool] = None # noqa: UP007
obd_src: Optional[str] = None # noqa: UP007
factory_default: Optional[bool] = None # noqa: UP007
def get_dict(self) -> dict:
"""Return a dict for this discovery result.
containing only the values actually set and with aliases as field names.
"""
return self.dict(
by_alias=False, exclude_unset=True, exclude_none=True, exclude_defaults=True
)