Add support for alternative discovery protocol (20002/udp) (#488)

This will broadcast the new discovery message on the new port and log any responses received as unsupported devices.

kasa/cli.py

@@ -103,6 +103,7 @@ def json_formatter_cb(result, **kwargs):
     "--port",
     envvar="KASA_PORT",
     required=False,
+    type=int,
     help="The port of the device to connect to.",
 )
 @click.option(
@@ -138,7 +139,17 @@ def json_formatter_cb(result, **kwargs):
 )
 @click.version_option(package_name="python-kasa")
 @click.pass_context
-async def cli(ctx, host, port, alias, target, debug, type, json, discovery_timeout):
+async def cli(
+    ctx,
+    host,
+    port,
+    alias,
+    target,
+    debug,
+    type,
+    json,
+    discovery_timeout,
+):
     """A tool for controlling TP-Link smart home devices."""  # noqa
     # no need to perform any checks if we are just displaying the help
     if sys.argv[-1] == "--help":
@@ -238,13 +249,29 @@ async def join(dev: SmartDevice, ssid, password, keytype):
 
 @cli.command()
 @click.option("--timeout", default=3, required=False)
+@click.option(
+    "--show-unsupported",
+    envvar="KASA_SHOW_UNSUPPORTED",
+    required=False,
+    default=False,
+    is_flag=True,
+    help="Print out discovered unsupported devices",
+)
 @click.pass_context
-async def discover(ctx, timeout):
+async def discover(ctx, timeout, show_unsupported):
     """Discover devices in the network."""
     target = ctx.parent.params["target"]
-    echo(f"Discovering devices on {target} for {timeout} seconds")
     sem = asyncio.Semaphore()
     discovered = dict()
+    unsupported = []
+
+    async def print_unsupported(data: Dict):
+        unsupported.append(data)
+        if show_unsupported:
+            echo(f"Found unsupported device (tapo/unknown encryption): {data}")
+            echo()
+
+    echo(f"Discovering devices on {target} for {timeout} seconds")
 
     async def print_discovered(dev: SmartDevice):
         await dev.update()
@@ -255,9 +282,23 @@ async def discover(ctx, timeout):
             echo()
 
     await Discover.discover(
-        target=target, timeout=timeout, on_discovered=print_discovered
+        target=target,
+        timeout=timeout,
+        on_discovered=print_discovered,
+        on_unsupported=print_unsupported,
     )
 
+    echo(f"Found {len(discovered)} devices")
+    if unsupported:
+        echo(
+            f"Found {len(unsupported)} unsupported devices"
+            + (
+                ""
+                if show_unsupported
+                else ", to show them use: kasa discover --show-unsupported"
+            )
+        )
+
     return discovered
 
 

kasa/discover.py

@@ -1,9 +1,15 @@
 """Discovery module for TP-Link Smart Home devices."""
 import asyncio
+import binascii
 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
+
+from kasa.exceptions import UnsupportedDeviceException
 from kasa.json import dumps as json_dumps
 from kasa.json import loads as json_loads
 from kasa.protocol import TPLinkSmartHomeProtocol
@@ -36,13 +42,22 @@ class _DiscoverProtocol(asyncio.DatagramProtocol):
         target: str = "255.255.255.255",
         discovery_packets: int = 3,
         interface: Optional[str] = None,
+        on_unsupported: Optional[Callable[[Dict], Awaitable[None]]] = None,
+        port: Optional[int] = None,
+        discovered_event: Optional[asyncio.Event] = None,
     ):
         self.transport = None
         self.discovery_packets = discovery_packets
         self.interface = interface
         self.on_discovered = on_discovered
-        self.target = (target, Discover.DISCOVERY_PORT)
+        self.discovery_port = port or Discover.DISCOVERY_PORT
+        self.target = (target, self.discovery_port)
+        self.target_2 = (target, Discover.DISCOVERY_PORT_2)
         self.discovered_devices = {}
+        self.unsupported_devices: Dict = {}
+        self.invalid_device_exceptions: Dict = {}
+        self.on_unsupported = on_unsupported
+        self.discovered_event = discovered_event
 
     def connection_made(self, transport) -> None:
         """Set socket options for broadcasting."""
@@ -69,23 +84,48 @@ class _DiscoverProtocol(asyncio.DatagramProtocol):
         encrypted_req = TPLinkSmartHomeProtocol.encrypt(req)
         for i in range(self.discovery_packets):
             self.transport.sendto(encrypted_req[4:], self.target)  # type: ignore
+            self.transport.sendto(Discover.DISCOVERY_QUERY_2, self.target_2)  # type: ignore
 
     def datagram_received(self, data, addr) -> None:
         """Handle discovery responses."""
         ip, port = addr
-        if ip in self.discovered_devices:
+        if (
+            ip in self.discovered_devices
+            or ip in self.unsupported_devices
+            or ip in self.invalid_device_exceptions
+        ):
             return
 
-        info = json_loads(TPLinkSmartHomeProtocol.decrypt(data))
+        if port == self.discovery_port:
-        _LOGGER.debug("[DISCOVERY] %s << %s", ip, info)
+            info = json_loads(TPLinkSmartHomeProtocol.decrypt(data))
+            _LOGGER.debug("[DISCOVERY] %s << %s", ip, info)
+
+        elif port == Discover.DISCOVERY_PORT_2:
+            info = json_loads(data[16:])
+            self.unsupported_devices[ip] = info
+            if self.on_unsupported is not None:
+                asyncio.ensure_future(self.on_unsupported(info))
+            _LOGGER.debug("[DISCOVERY] Unsupported device found at %s << %s", ip, info)
+            if self.discovered_event is not None and "255" not in self.target[0].split(
+                "."
+            ):
+                self.discovered_event.set()
+            return
 
         try:
             device_class = Discover._get_device_class(info)
         except SmartDeviceException as ex:
-            _LOGGER.debug("Unable to find device type from %s: %s", info, ex)
+            _LOGGER.debug(
+                "[DISCOVERY] Unable to find device type from %s: %s", info, ex
+            )
+            self.invalid_device_exceptions[ip] = ex
+            if self.discovered_event is not None and "255" not in self.target[0].split(
+                "."
+            ):
+                self.discovered_event.set()
             return
 
-        device = device_class(ip)
+        device = device_class(ip, port=port)
         device.update_from_discover_info(info)
 
         self.discovered_devices[ip] = device
@@ -93,6 +133,9 @@ class _DiscoverProtocol(asyncio.DatagramProtocol):
         if self.on_discovered is not None:
             asyncio.ensure_future(self.on_discovered(device))
 
+        if self.discovered_event is not None and "255" not in self.target[0].split("."):
+            self.discovered_event.set()
+
     def error_received(self, ex):
         """Handle asyncio.Protocol errors."""
         _LOGGER.error("Got error: %s", ex)
@@ -142,6 +185,9 @@ class Discover:
         "system": {"get_sysinfo": None},
     }
 
+    DISCOVERY_PORT_2 = 20002
+    DISCOVERY_QUERY_2 = binascii.unhexlify("020000010000000000000000463cb5d3")
+
     @staticmethod
     async def discover(
         *,
@@ -150,6 +196,7 @@ class Discover:
         timeout=5,
         discovery_packets=3,
         interface=None,
+        on_unsupported=None,
     ) -> DeviceDict:
         """Discover supported devices.
 
@@ -177,6 +224,7 @@ class Discover:
                 on_discovered=on_discovered,
                 discovery_packets=discovery_packets,
                 interface=interface,
+                on_unsupported=on_unsupported,
             ),
             local_addr=("0.0.0.0", 0),
         )
@@ -193,22 +241,47 @@ class Discover:
         return protocol.discovered_devices
 
     @staticmethod
-    async def discover_single(host: str, *, port: Optional[int] = None) -> SmartDevice:
+    async def discover_single(
+        host: str, *, port: Optional[int] = None, timeout=5
+    ) -> SmartDevice:
         """Discover a single device by the given IP address.
 
         :param host: Hostname of device to query
         :rtype: SmartDevice
         :return: Object for querying/controlling found device.
         """
-        protocol = TPLinkSmartHomeProtocol(host, port=port)
+        loop = asyncio.get_event_loop()
+        event = asyncio.Event()
+        transport, protocol = await loop.create_datagram_endpoint(
+            lambda: _DiscoverProtocol(target=host, port=port, discovered_event=event),
+            local_addr=("0.0.0.0", 0),
+        )
+        protocol = cast(_DiscoverProtocol, protocol)
 
-        info = await protocol.query(Discover.DISCOVERY_QUERY)
+        try:
+            _LOGGER.debug("Waiting a total of %s seconds for responses...", timeout)
 
-        device_class = Discover._get_device_class(info)
+            async with asyncio_timeout(timeout):
-        dev = device_class(host, port=port)
+                await event.wait()
-        await dev.update()
+        except asyncio.TimeoutError:
+            raise SmartDeviceException(
+                f"Timed out getting discovery response for {host}"
+            )
+        finally:
+            transport.close()
 
-        return dev
+        if host in protocol.discovered_devices:
+            dev = protocol.discovered_devices[host]
+            await dev.update()
+            return dev
+        elif host in protocol.unsupported_devices:
+            raise UnsupportedDeviceException(
+                f"Unsupported device {host}: {protocol.unsupported_devices[host]}"
+            )
+        elif host in protocol.invalid_device_exceptions:
+            raise protocol.invalid_device_exceptions[host]
+        else:
+            raise SmartDeviceException(f"Unable to get discovery response for {host}")
 
     @staticmethod
     def _get_device_class(info: dict) -> Type[SmartDevice]:

kasa/exceptions.py

@@ -3,3 +3,7 @@
 
 class SmartDeviceException(Exception):
     """Base exception for device errors."""
+
+
+class UnsupportedDeviceException(SmartDeviceException):
+    """Exception for trying to connect to unsupported devices."""

kasa/tests/test_discovery.py

@@ -1,10 +1,12 @@
 # type: ignore
+import re
 import sys
 
 import pytest  # type: ignore # https://github.com/pytest-dev/pytest/issues/3342
 
 from kasa import DeviceType, Discover, SmartDevice, SmartDeviceException, protocol
-from kasa.discover import _DiscoverProtocol
+from kasa.discover import _DiscoverProtocol, json_dumps
+from kasa.exceptions import UnsupportedDeviceException
 
 from .conftest import bulb, dimmer, lightstrip, plug, strip
 
@@ -55,11 +57,73 @@ async def test_type_unknown():
 @pytest.mark.parametrize("custom_port", [123, None])
 async def test_discover_single(discovery_data: dict, mocker, custom_port):
     """Make sure that discover_single returns an initialized SmartDevice instance."""
+    host = "127.0.0.1"
+
+    def mock_discover(self):
+        self.datagram_received(
+            protocol.TPLinkSmartHomeProtocol.encrypt(json_dumps(discovery_data))[4:],
+            (host, custom_port or 9999),
+        )
+
+    mocker.patch.object(_DiscoverProtocol, "do_discover", mock_discover)
     mocker.patch("kasa.TPLinkSmartHomeProtocol.query", return_value=discovery_data)
-    x = await Discover.discover_single("127.0.0.1", port=custom_port)
+
+    x = await Discover.discover_single(host, port=custom_port)
     assert issubclass(x.__class__, SmartDevice)
     assert x._sys_info is not None
-    assert x.port == custom_port
+    assert x.port == custom_port or 9999
+
+
+UNSUPPORTED = {
+    "result": {
+        "device_id": "xx",
+        "owner": "xx",
+        "device_type": "SMART.TAPOPLUG",
+        "device_model": "P110(EU)",
+        "ip": "127.0.0.1",
+        "mac": "48-22xxx",
+        "is_support_iot_cloud": True,
+        "obd_src": "tplink",
+        "factory_default": False,
+        "mgt_encrypt_schm": {
+            "is_support_https": False,
+            "encrypt_type": "AES",
+            "http_port": 80,
+            "lv": 2,
+        },
+    },
+    "error_code": 0,
+}
+
+
+async def test_discover_single_unsupported(mocker):
+    """Make sure that discover_single handles unsupported devices correctly."""
+    host = "127.0.0.1"
+
+    def mock_discover(self):
+        if discovery_data:
+            data = (
+                b"\x02\x00\x00\x01\x01[\x00\x00\x00\x00\x00\x00W\xcev\xf8"
+                + json_dumps(discovery_data).encode()
+            )
+            self.datagram_received(data, (host, 20002))
+
+    mocker.patch.object(_DiscoverProtocol, "do_discover", mock_discover)
+
+    # Test with a valid unsupported response
+    discovery_data = UNSUPPORTED
+    with pytest.raises(
+        UnsupportedDeviceException,
+        match=f"Unsupported device {host}: {re.escape(str(UNSUPPORTED))}",
+    ):
+        await Discover.discover_single(host)
+
+    # Test with no response
+    discovery_data = None
+    with pytest.raises(
+        SmartDeviceException, match=f"Timed out getting discovery response for {host}"
+    ):
+        await Discover.discover_single(host, timeout=0.001)
 
 
 INVALIDS = [
@@ -75,9 +139,17 @@ INVALIDS = [
 @pytest.mark.parametrize("msg, data", INVALIDS)
 async def test_discover_invalid_info(msg, data, mocker):
     """Make sure that invalid discovery information raises an exception."""
-    mocker.patch("kasa.TPLinkSmartHomeProtocol.query", return_value=data)
+    host = "127.0.0.1"
+
+    def mock_discover(self):
+        self.datagram_received(
+            protocol.TPLinkSmartHomeProtocol.encrypt(json_dumps(data))[4:], (host, 9999)
+        )
+
+    mocker.patch.object(_DiscoverProtocol, "do_discover", mock_discover)
+
     with pytest.raises(SmartDeviceException, match=msg):
-        await Discover.discover_single("127.0.0.1")
+        await Discover.discover_single(host)
 
 
 async def test_discover_send(mocker):
@@ -87,7 +159,7 @@ async def test_discover_send(mocker):
     assert proto.target == ("255.255.255.255", 9999)
     transport = mocker.patch.object(proto, "transport")
     proto.do_discover()
-    assert transport.sendto.call_count == proto.discovery_packets
+    assert transport.sendto.call_count == proto.discovery_packets * 2
 
 
 async def test_discover_datagram_received(mocker, discovery_data):
@@ -98,10 +170,14 @@ async def test_discover_datagram_received(mocker, discovery_data):
     mocker.patch.object(protocol.TPLinkSmartHomeProtocol, "decrypt")
 
     addr = "127.0.0.1"
-    proto.datagram_received("<placeholder data>", (addr, 1234))
+    proto.datagram_received("<placeholder data>", (addr, 9999))
+    addr2 = "127.0.0.2"
+    proto.datagram_received("<placeholder data>", (addr2, 20002))
 
     # Check that device in discovered_devices is initialized correctly
     assert len(proto.discovered_devices) == 1
+    # Check that unsupported device is 1
+    assert len(proto.unsupported_devices) == 1
     dev = proto.discovered_devices[addr]
     assert issubclass(dev.__class__, SmartDevice)
     assert dev.host == addr
@@ -115,5 +191,5 @@ async def test_discover_invalid_responses(msg, data, mocker):
     mocker.patch.object(protocol.TPLinkSmartHomeProtocol, "encrypt")
     mocker.patch.object(protocol.TPLinkSmartHomeProtocol, "decrypt")
 
-    proto.datagram_received(data, ("127.0.0.1", 1234))
+    proto.datagram_received(data, ("127.0.0.1", 9999))
     assert len(proto.discovered_devices) == 0