python-kasa/kasa/protocol.py

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"""Implementation of the TP-Link Smart Home Protocol.
Encryption/Decryption methods based on the works of
Lubomir Stroetmann and Tobias Esser
https://www.softscheck.com/en/reverse-engineering-tp-link-hs110/
https://github.com/softScheck/tplink-smartplug/
which are licensed under the Apache License, Version 2.0
http://www.apache.org/licenses/LICENSE-2.0
"""
import asyncio
import contextlib
import json
import logging
import struct
from pprint import pformat as pf
from typing import Dict, Optional, Union
from .exceptions import SmartDeviceException
_LOGGER = logging.getLogger(__name__)
class TPLinkSmartHomeProtocol:
"""Implementation of the TP-Link Smart Home protocol."""
API and tests cleanup (#151) * Add new cli commands: raw_command and dump_discover - raw_command can be used to execute raw commands with given parameters * Useful for testing new calls before implementing them properly - dump_discover can be used to dump the device discovery information (into a file) * The discovery is extended to request more modules and methods from devices * smartlife.iot.dimmer get_dimmer_parameters * smartlife.iot.common.emeter get_realtime * smartlife.iot.smartbulb.lightingservice get_light_state * This is used to dump more information for proper tests, and will also allow better discovery in the future This commit contains also some documentation updates and dropping click_datetime in favor of click's built-in datetime * Docstring fixes * Major API cleanup Properties shall no more change the state of the device, this work in still in progress, the main goal being making the API more user-friendly and to make implementing new features simpler. The newly deprecated functionality will remain working and will simply warn the user about deprecation. Previously deprecated 'features' property and 'identify' method are now finally removed. Deprecate and replace the following property setters: * state with turn_on() and turn_off() * hsv with set_hsv() * color_temp with set_color_temp() * brightness with set_brightness() * led with set_led() * alias with set_alias() * mac with set_mac() And getters: * state with is_on and is_off The {BULB,PLUG}_STATE_{ON,OFF} is simplified to STATE_ON and STATE_OFF, UNKNOWN state is removed. These are now deprecated and will be removed in the future. * is_on and is_off can be used to check for the state * turn_on() and turn_off() for changing the device state. Trying to use functionality not supported by the device will cause SmartDeviceExceptions instead of failing silently and/or returning None. This includes, e.g., trying to set a color temperature on non-supported bulb. ValueErrors are raised instead of SmartDeviceExceptions where appropriate (e.g. when trying to set an invalid hsv or brightness). New enum type DeviceType is added to allow detecting device types without resorting to isinstance() calling. SmartDevice class' device_type property can be used to query the type. is_plug and is_bulb helpers are added. * Cleanup tests and improve test coverage * Make writing tests easier by sharing code for common implementations * Instead of storing test data inside python files, dump-discover based information is used * This will simplify adding new tests and remove code duplication * fixtures are based on https://github.com/plasticrake/tplink-smarthome-simulator * run black on newfakes * Add HS300 tests and update SmartStrip API according to earlier changes, still WIP * run black and avoid wildcard imports * Black on conftest * bump minimum required version to 3.5 * Rename fixture_tests to test_fixtures for autocollect * fix typoed type to _type, black * run black on several files with -79 to fix hound issues * Fix broken merge on hue * Fix tests (hue update, pass context to smartdevice), add is_strip property, disable emeter tests for HS300 until a solution for API is found. * Fix old tests * Run black on changed files * Add real HS220 discovery, thanks to @poiyo * add is_dimmable and is_variable_color_temp to smartdevice class, simplifies interfacing with homeassistant * add KL120(US) fixture * Add a simple query cache This commit adds a simple query cache to speed up the process for users requesting lots of different properties from the device, as done by the cli tool as well as homeassistant. The logic for caching is very simple: 1. A timestamp for last fetch for each module+command is stored alongside the response. 2. If the issued command starts with `get_` and the TTL has not expired, the cache result is returned. 3. Otherwise the cache for the whole corresponding module gets invalidated, the device will be queried and the result will be stored in the cache. * add deprecation to tox.ini * make tests pass again * remove old tests, add flake8 to tox reqs * run black against pyhs100 module, add it to precommit hooks, fix flake8 configuration to conform to black standards (https://ljvmiranda921.github.io/notebook/2018/06/21/precommits-using-black-and-flake8/) * fix syntax * cleanup conftest
2019-06-16 21:05:00 +00:00
INITIALIZATION_VECTOR = 171
DEFAULT_PORT = 9999
DEFAULT_TIMEOUT = 5
BLOCK_SIZE = 4
def __init__(self, host: str) -> None:
"""Create a protocol object."""
self.host = host
self.reader: Optional[asyncio.StreamReader] = None
self.writer: Optional[asyncio.StreamWriter] = None
self.query_lock: Optional[asyncio.Lock] = None
self.loop: Optional[asyncio.AbstractEventLoop] = None
def _detect_event_loop_change(self) -> None:
"""Check if this object has been reused betwen event loops."""
loop = asyncio.get_running_loop()
if not self.loop:
self.loop = loop
elif self.loop != loop:
_LOGGER.warning("Detected protocol reuse between different event loop")
self._reset()
async def query(self, request: Union[str, Dict], retry_count: int = 3) -> Dict:
API and tests cleanup (#151) * Add new cli commands: raw_command and dump_discover - raw_command can be used to execute raw commands with given parameters * Useful for testing new calls before implementing them properly - dump_discover can be used to dump the device discovery information (into a file) * The discovery is extended to request more modules and methods from devices * smartlife.iot.dimmer get_dimmer_parameters * smartlife.iot.common.emeter get_realtime * smartlife.iot.smartbulb.lightingservice get_light_state * This is used to dump more information for proper tests, and will also allow better discovery in the future This commit contains also some documentation updates and dropping click_datetime in favor of click's built-in datetime * Docstring fixes * Major API cleanup Properties shall no more change the state of the device, this work in still in progress, the main goal being making the API more user-friendly and to make implementing new features simpler. The newly deprecated functionality will remain working and will simply warn the user about deprecation. Previously deprecated 'features' property and 'identify' method are now finally removed. Deprecate and replace the following property setters: * state with turn_on() and turn_off() * hsv with set_hsv() * color_temp with set_color_temp() * brightness with set_brightness() * led with set_led() * alias with set_alias() * mac with set_mac() And getters: * state with is_on and is_off The {BULB,PLUG}_STATE_{ON,OFF} is simplified to STATE_ON and STATE_OFF, UNKNOWN state is removed. These are now deprecated and will be removed in the future. * is_on and is_off can be used to check for the state * turn_on() and turn_off() for changing the device state. Trying to use functionality not supported by the device will cause SmartDeviceExceptions instead of failing silently and/or returning None. This includes, e.g., trying to set a color temperature on non-supported bulb. ValueErrors are raised instead of SmartDeviceExceptions where appropriate (e.g. when trying to set an invalid hsv or brightness). New enum type DeviceType is added to allow detecting device types without resorting to isinstance() calling. SmartDevice class' device_type property can be used to query the type. is_plug and is_bulb helpers are added. * Cleanup tests and improve test coverage * Make writing tests easier by sharing code for common implementations * Instead of storing test data inside python files, dump-discover based information is used * This will simplify adding new tests and remove code duplication * fixtures are based on https://github.com/plasticrake/tplink-smarthome-simulator * run black on newfakes * Add HS300 tests and update SmartStrip API according to earlier changes, still WIP * run black and avoid wildcard imports * Black on conftest * bump minimum required version to 3.5 * Rename fixture_tests to test_fixtures for autocollect * fix typoed type to _type, black * run black on several files with -79 to fix hound issues * Fix broken merge on hue * Fix tests (hue update, pass context to smartdevice), add is_strip property, disable emeter tests for HS300 until a solution for API is found. * Fix old tests * Run black on changed files * Add real HS220 discovery, thanks to @poiyo * add is_dimmable and is_variable_color_temp to smartdevice class, simplifies interfacing with homeassistant * add KL120(US) fixture * Add a simple query cache This commit adds a simple query cache to speed up the process for users requesting lots of different properties from the device, as done by the cli tool as well as homeassistant. The logic for caching is very simple: 1. A timestamp for last fetch for each module+command is stored alongside the response. 2. If the issued command starts with `get_` and the TTL has not expired, the cache result is returned. 3. Otherwise the cache for the whole corresponding module gets invalidated, the device will be queried and the result will be stored in the cache. * add deprecation to tox.ini * make tests pass again * remove old tests, add flake8 to tox reqs * run black against pyhs100 module, add it to precommit hooks, fix flake8 configuration to conform to black standards (https://ljvmiranda921.github.io/notebook/2018/06/21/precommits-using-black-and-flake8/) * fix syntax * cleanup conftest
2019-06-16 21:05:00 +00:00
"""Request information from a TP-Link SmartHome Device.
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:param str host: host name or ip address of the device
:param request: command to send to the device (can be either dict or
json string)
:param retry_count: how many retries to do in case of failure
API and tests cleanup (#151) * Add new cli commands: raw_command and dump_discover - raw_command can be used to execute raw commands with given parameters * Useful for testing new calls before implementing them properly - dump_discover can be used to dump the device discovery information (into a file) * The discovery is extended to request more modules and methods from devices * smartlife.iot.dimmer get_dimmer_parameters * smartlife.iot.common.emeter get_realtime * smartlife.iot.smartbulb.lightingservice get_light_state * This is used to dump more information for proper tests, and will also allow better discovery in the future This commit contains also some documentation updates and dropping click_datetime in favor of click's built-in datetime * Docstring fixes * Major API cleanup Properties shall no more change the state of the device, this work in still in progress, the main goal being making the API more user-friendly and to make implementing new features simpler. The newly deprecated functionality will remain working and will simply warn the user about deprecation. Previously deprecated 'features' property and 'identify' method are now finally removed. Deprecate and replace the following property setters: * state with turn_on() and turn_off() * hsv with set_hsv() * color_temp with set_color_temp() * brightness with set_brightness() * led with set_led() * alias with set_alias() * mac with set_mac() And getters: * state with is_on and is_off The {BULB,PLUG}_STATE_{ON,OFF} is simplified to STATE_ON and STATE_OFF, UNKNOWN state is removed. These are now deprecated and will be removed in the future. * is_on and is_off can be used to check for the state * turn_on() and turn_off() for changing the device state. Trying to use functionality not supported by the device will cause SmartDeviceExceptions instead of failing silently and/or returning None. This includes, e.g., trying to set a color temperature on non-supported bulb. ValueErrors are raised instead of SmartDeviceExceptions where appropriate (e.g. when trying to set an invalid hsv or brightness). New enum type DeviceType is added to allow detecting device types without resorting to isinstance() calling. SmartDevice class' device_type property can be used to query the type. is_plug and is_bulb helpers are added. * Cleanup tests and improve test coverage * Make writing tests easier by sharing code for common implementations * Instead of storing test data inside python files, dump-discover based information is used * This will simplify adding new tests and remove code duplication * fixtures are based on https://github.com/plasticrake/tplink-smarthome-simulator * run black on newfakes * Add HS300 tests and update SmartStrip API according to earlier changes, still WIP * run black and avoid wildcard imports * Black on conftest * bump minimum required version to 3.5 * Rename fixture_tests to test_fixtures for autocollect * fix typoed type to _type, black * run black on several files with -79 to fix hound issues * Fix broken merge on hue * Fix tests (hue update, pass context to smartdevice), add is_strip property, disable emeter tests for HS300 until a solution for API is found. * Fix old tests * Run black on changed files * Add real HS220 discovery, thanks to @poiyo * add is_dimmable and is_variable_color_temp to smartdevice class, simplifies interfacing with homeassistant * add KL120(US) fixture * Add a simple query cache This commit adds a simple query cache to speed up the process for users requesting lots of different properties from the device, as done by the cli tool as well as homeassistant. The logic for caching is very simple: 1. A timestamp for last fetch for each module+command is stored alongside the response. 2. If the issued command starts with `get_` and the TTL has not expired, the cache result is returned. 3. Otherwise the cache for the whole corresponding module gets invalidated, the device will be queried and the result will be stored in the cache. * add deprecation to tox.ini * make tests pass again * remove old tests, add flake8 to tox reqs * run black against pyhs100 module, add it to precommit hooks, fix flake8 configuration to conform to black standards (https://ljvmiranda921.github.io/notebook/2018/06/21/precommits-using-black-and-flake8/) * fix syntax * cleanup conftest
2019-06-16 21:05:00 +00:00
:return: response dict
"""
self._detect_event_loop_change()
if not self.query_lock:
self.query_lock = asyncio.Lock()
if isinstance(request, dict):
request = json.dumps(request)
assert isinstance(request, str)
2018-01-17 21:03:19 +00:00
timeout = TPLinkSmartHomeProtocol.DEFAULT_TIMEOUT
async with self.query_lock:
return await self._query(request, retry_count, timeout)
async def _connect(self, timeout: int) -> bool:
"""Try to connect or reconnect to the device."""
if self.writer:
return True
with contextlib.suppress(Exception):
self.reader = self.writer = None
task = asyncio.open_connection(
self.host, TPLinkSmartHomeProtocol.DEFAULT_PORT
)
self.reader, self.writer = await asyncio.wait_for(task, timeout=timeout)
return True
return False
async def _execute_query(self, request: str) -> Dict:
"""Execute a query on the device and wait for the response."""
assert self.writer is not None
assert self.reader is not None
_LOGGER.debug("> (%i) %s", len(request), request)
self.writer.write(TPLinkSmartHomeProtocol.encrypt(request))
await self.writer.drain()
packed_block_size = await self.reader.readexactly(self.BLOCK_SIZE)
length = struct.unpack(">I", packed_block_size)[0]
buffer = await self.reader.readexactly(length)
response = TPLinkSmartHomeProtocol.decrypt(buffer)
json_payload = json.loads(response)
_LOGGER.debug("< (%i) %s", len(response), pf(json_payload))
return json_payload
async def close(self):
"""Close the connection."""
writer = self.writer
self._reset()
if writer:
writer.close()
with contextlib.suppress(Exception):
await writer.wait_closed()
def _reset(self):
"""Clear any varibles that should not survive between loops."""
self.writer = None
self.reader = None
self.query_lock = None
self.loop = None
async def _query(self, request: str, retry_count: int, timeout: int) -> Dict:
"""Try to query a device."""
for retry in range(retry_count + 1):
if not await self._connect(timeout):
await self.close()
if retry >= retry_count:
_LOGGER.debug("Giving up after %s retries", retry)
raise SmartDeviceException(
f"Unable to connect to the device: {self.host}"
)
continue
try:
assert self.reader is not None
assert self.writer is not None
return await asyncio.wait_for(
self._execute_query(request), timeout=timeout
)
except Exception as ex:
await self.close()
if retry >= retry_count:
_LOGGER.debug("Giving up after %s retries", retry)
raise SmartDeviceException(
f"Unable to query the device: {ex}"
) from ex
_LOGGER.debug("Unable to query the device, retrying: %s", ex)
# make mypy happy, this should never be reached..
await self.close()
raise SmartDeviceException("Query reached somehow to unreachable")
def __del__(self):
if self.writer and self.loop and self.loop.is_running():
self.writer.close()
self._reset()
@staticmethod
def _xor_payload(unencrypted):
key = TPLinkSmartHomeProtocol.INITIALIZATION_VECTOR
for unencryptedbyte in unencrypted:
key = key ^ unencryptedbyte
yield key
@staticmethod
def encrypt(request: str) -> bytes:
"""Encrypt a request for a TP-Link Smart Home Device.
:param request: plaintext request data
:return: ciphertext to be send over wire, in bytes
"""
plainbytes = request.encode()
return struct.pack(">I", len(plainbytes)) + bytes(
TPLinkSmartHomeProtocol._xor_payload(plainbytes)
)
@staticmethod
def _xor_encrypted_payload(ciphertext):
key = TPLinkSmartHomeProtocol.INITIALIZATION_VECTOR
for cipherbyte in ciphertext:
plainbyte = key ^ cipherbyte
key = cipherbyte
yield plainbyte
@staticmethod
def decrypt(ciphertext: bytes) -> str:
"""Decrypt a response of a TP-Link Smart Home Device.
:param ciphertext: encrypted response data
:return: plaintext response
"""
return bytes(
TPLinkSmartHomeProtocol._xor_encrypted_payload(ciphertext)
).decode()