mirror of
https://github.com/python-kasa/python-kasa.git
synced 2024-12-23 03:33:35 +00:00
9dc0cbaece
* Add retries to query(), defaults to 3 + add tests * Catch also json decoding errors for retries * add missing exceptions file, fix old protocol tests
129 lines
4.3 KiB
Python
Executable File
129 lines
4.3 KiB
Python
Executable File
"""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 json
|
|
import logging
|
|
import struct
|
|
from pprint import pformat as pf
|
|
from typing import Dict, Union
|
|
|
|
from .exceptions import SmartDeviceException
|
|
|
|
_LOGGER = logging.getLogger(__name__)
|
|
|
|
|
|
class TPLinkSmartHomeProtocol:
|
|
"""Implementation of the TP-Link Smart Home protocol."""
|
|
|
|
INITIALIZATION_VECTOR = 171
|
|
DEFAULT_PORT = 9999
|
|
DEFAULT_TIMEOUT = 5
|
|
|
|
@staticmethod
|
|
async def query(host: str, request: Union[str, Dict], retry_count: int = 3) -> Dict:
|
|
"""Request information from a TP-Link SmartHome Device.
|
|
|
|
: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
|
|
:return: response dict
|
|
"""
|
|
if isinstance(request, dict):
|
|
request = json.dumps(request)
|
|
|
|
timeout = TPLinkSmartHomeProtocol.DEFAULT_TIMEOUT
|
|
writer = None
|
|
for retry in range(retry_count + 1):
|
|
try:
|
|
task = asyncio.open_connection(
|
|
host, TPLinkSmartHomeProtocol.DEFAULT_PORT
|
|
)
|
|
reader, writer = await asyncio.wait_for(task, timeout=timeout)
|
|
_LOGGER.debug("> (%i) %s", len(request), request)
|
|
writer.write(TPLinkSmartHomeProtocol.encrypt(request))
|
|
await writer.drain()
|
|
|
|
buffer = bytes()
|
|
# Some devices send responses with a length header of 0 and
|
|
# terminate with a zero size chunk. Others send the length and
|
|
# will hang if we attempt to read more data.
|
|
length = -1
|
|
while True:
|
|
chunk = await reader.read(4096)
|
|
if length == -1:
|
|
length = struct.unpack(">I", chunk[0:4])[0]
|
|
buffer += chunk
|
|
if (length > 0 and len(buffer) >= length + 4) or not chunk:
|
|
break
|
|
|
|
response = TPLinkSmartHomeProtocol.decrypt(buffer[4:])
|
|
json_payload = json.loads(response)
|
|
_LOGGER.debug("< (%i) %s", len(response), pf(json_payload))
|
|
|
|
return json_payload
|
|
|
|
except Exception as ex:
|
|
if retry >= retry_count:
|
|
_LOGGER.debug("Giving up after %s retries", retry)
|
|
raise SmartDeviceException(
|
|
"Unable to query the device: %s" % ex
|
|
) from ex
|
|
|
|
_LOGGER.debug("Unable to query the device, retrying: %s", ex)
|
|
|
|
finally:
|
|
if writer:
|
|
writer.close()
|
|
await writer.wait_closed()
|
|
|
|
# make mypy happy, this should never be reached..
|
|
raise SmartDeviceException("Query reached somehow to unreachable")
|
|
|
|
@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
|
|
"""
|
|
key = TPLinkSmartHomeProtocol.INITIALIZATION_VECTOR
|
|
|
|
plainbytes = request.encode()
|
|
buffer = bytearray(struct.pack(">I", len(plainbytes)))
|
|
|
|
for plainbyte in plainbytes:
|
|
cipherbyte = key ^ plainbyte
|
|
key = cipherbyte
|
|
buffer.append(cipherbyte)
|
|
|
|
return bytes(buffer)
|
|
|
|
@staticmethod
|
|
def decrypt(ciphertext: bytes) -> str:
|
|
"""Decrypt a response of a TP-Link Smart Home Device.
|
|
|
|
:param ciphertext: encrypted response data
|
|
:return: plaintext response
|
|
"""
|
|
key = TPLinkSmartHomeProtocol.INITIALIZATION_VECTOR
|
|
buffer = []
|
|
|
|
for cipherbyte in ciphertext:
|
|
plainbyte = key ^ cipherbyte
|
|
key = cipherbyte
|
|
buffer.append(plainbyte)
|
|
|
|
plaintext = bytes(buffer)
|
|
|
|
return plaintext.decode()
|