mirror of
https://github.com/esphome/esphome.git
synced 2024-11-30 02:34:12 +01:00
d9cf91210e
* Add local mDNS responder * Fix * Use mDNS in dashboard status * Lint * Lint * Fix test * Remove hostname * Fix use enum * Lint
780 lines
24 KiB
Python
780 lines
24 KiB
Python
# Custom zeroconf implementation based on python-zeroconf
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# (https://github.com/jstasiak/python-zeroconf) that supports Python 2
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import errno
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import logging
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import select
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import socket
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import struct
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import sys
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import threading
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import time
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import ifaddr
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from esphomeyaml.py_compat import indexbytes, text_type
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log = logging.getLogger(__name__)
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# Some timing constants
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_LISTENER_TIME = 200
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# Some DNS constants
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_MDNS_ADDR = '224.0.0.251'
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_MDNS_PORT = 5353
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_MAX_MSG_ABSOLUTE = 8966
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_FLAGS_QR_MASK = 0x8000 # query response mask
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_FLAGS_QR_QUERY = 0x0000 # query
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_FLAGS_QR_RESPONSE = 0x8000 # response
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_FLAGS_AA = 0x0400 # Authoritative answer
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_FLAGS_TC = 0x0200 # Truncated
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_FLAGS_RD = 0x0100 # Recursion desired
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_FLAGS_RA = 0x8000 # Recursion available
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_FLAGS_Z = 0x0040 # Zero
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_FLAGS_AD = 0x0020 # Authentic data
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_FLAGS_CD = 0x0010 # Checking disabled
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_CLASS_IN = 1
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_CLASS_CS = 2
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_CLASS_CH = 3
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_CLASS_HS = 4
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_CLASS_NONE = 254
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_CLASS_ANY = 255
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_CLASS_MASK = 0x7FFF
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_CLASS_UNIQUE = 0x8000
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_TYPE_A = 1
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_TYPE_NS = 2
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_TYPE_MD = 3
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_TYPE_MF = 4
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_TYPE_CNAME = 5
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_TYPE_SOA = 6
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_TYPE_MB = 7
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_TYPE_MG = 8
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_TYPE_MR = 9
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_TYPE_NULL = 10
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_TYPE_WKS = 11
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_TYPE_PTR = 12
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_TYPE_HINFO = 13
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_TYPE_MINFO = 14
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_TYPE_MX = 15
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_TYPE_TXT = 16
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_TYPE_AAAA = 28
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_TYPE_SRV = 33
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_TYPE_ANY = 255
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# Mapping constants to names
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int2byte = struct.Struct(">B").pack
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# Exceptions
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class Error(Exception):
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pass
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class IncomingDecodeError(Error):
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pass
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# pylint: disable=no-init
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class QuietLogger(object):
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_seen_logs = {}
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@classmethod
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def log_exception_warning(cls, logger_data=None):
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exc_info = sys.exc_info()
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exc_str = str(exc_info[1])
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if exc_str not in cls._seen_logs:
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# log at warning level the first time this is seen
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cls._seen_logs[exc_str] = exc_info
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logger = log.warning
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else:
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logger = log.debug
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if logger_data is not None:
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logger(*logger_data)
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logger('Exception occurred:', exc_info=True)
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@classmethod
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def log_warning_once(cls, *args):
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msg_str = args[0]
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if msg_str not in cls._seen_logs:
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cls._seen_logs[msg_str] = 0
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logger = log.warning
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else:
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logger = log.debug
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cls._seen_logs[msg_str] += 1
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logger(*args)
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class DNSEntry(object):
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"""A DNS entry"""
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def __init__(self, name, type_, class_):
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self.key = name.lower()
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self.name = name
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self.type = type_
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self.class_ = class_ & _CLASS_MASK
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self.unique = (class_ & _CLASS_UNIQUE) != 0
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class DNSQuestion(DNSEntry):
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"""A DNS question entry"""
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def __init__(self, name, type_, class_):
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DNSEntry.__init__(self, name, type_, class_)
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def answered_by(self, rec):
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"""Returns true if the question is answered by the record"""
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return (self.class_ == rec.class_ and
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(self.type == rec.type or self.type == _TYPE_ANY) and
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self.name == rec.name)
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class DNSRecord(DNSEntry):
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"""A DNS record - like a DNS entry, but has a TTL"""
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def __init__(self, name, type_, class_, ttl):
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DNSEntry.__init__(self, name, type_, class_)
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self.ttl = 15
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self.created = time.time()
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def write(self, out):
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"""Abstract method"""
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raise NotImplementedError
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def is_expired(self, now):
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return self.created + self.ttl <= now
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def is_removable(self, now):
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return self.created + self.ttl * 2 <= now
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class DNSAddress(DNSRecord):
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"""A DNS address record"""
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def __init__(self, name, type_, class_, ttl, address):
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DNSRecord.__init__(self, name, type_, class_, ttl)
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self.address = address
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def write(self, out):
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"""Used in constructing an outgoing packet"""
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out.write_string(self.address)
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class DNSText(DNSRecord):
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"""A DNS text record"""
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def __init__(self, name, type_, class_, ttl, text):
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assert isinstance(text, (bytes, type(None)))
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DNSRecord.__init__(self, name, type_, class_, ttl)
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self.text = text
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def write(self, out):
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"""Used in constructing an outgoing packet"""
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out.write_string(self.text)
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class DNSIncoming(QuietLogger):
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"""Object representation of an incoming DNS packet"""
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def __init__(self, data):
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"""Constructor from string holding bytes of packet"""
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self.offset = 0
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self.data = data
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self.questions = []
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self.answers = []
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self.id = 0
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self.flags = 0 # type: int
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self.num_questions = 0
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self.num_answers = 0
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self.num_authorities = 0
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self.num_additionals = 0
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self.valid = False
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try:
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self.read_header()
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self.read_questions()
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self.read_others()
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self.valid = True
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except (IndexError, struct.error, IncomingDecodeError):
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self.log_exception_warning((
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'Choked at offset %d while unpacking %r', self.offset, data))
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def unpack(self, format_):
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length = struct.calcsize(format_)
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info = struct.unpack(
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format_, self.data[self.offset:self.offset + length])
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self.offset += length
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return info
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def read_header(self):
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"""Reads header portion of packet"""
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(self.id, self.flags, self.num_questions, self.num_answers,
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self.num_authorities, self.num_additionals) = self.unpack(b'!6H')
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def read_questions(self):
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"""Reads questions section of packet"""
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for _ in range(self.num_questions):
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name = self.read_name()
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type_, class_ = self.unpack(b'!HH')
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question = DNSQuestion(name, type_, class_)
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self.questions.append(question)
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def read_character_string(self):
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"""Reads a character string from the packet"""
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length = self.data[self.offset]
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self.offset += 1
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return self.read_string(length)
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def read_string(self, length):
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"""Reads a string of a given length from the packet"""
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info = self.data[self.offset:self.offset + length]
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self.offset += length
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return info
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def read_unsigned_short(self):
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"""Reads an unsigned short from the packet"""
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return self.unpack(b'!H')[0]
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def read_others(self):
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"""Reads the answers, authorities and additionals section of the
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packet"""
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n = self.num_answers + self.num_authorities + self.num_additionals
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for _ in range(n):
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domain = self.read_name()
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type_, class_, ttl, length = self.unpack(b'!HHiH')
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rec = None
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if type_ == _TYPE_A:
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rec = DNSAddress(
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domain, type_, class_, ttl, self.read_string(4))
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elif type_ == _TYPE_TXT:
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rec = DNSText(
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domain, type_, class_, ttl, self.read_string(length))
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elif type_ == _TYPE_AAAA:
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rec = DNSAddress(
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domain, type_, class_, ttl, self.read_string(16))
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else:
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# Try to ignore types we don't know about
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# Skip the payload for the resource record so the next
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# records can be parsed correctly
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self.offset += length
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if rec is not None:
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self.answers.append(rec)
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def is_query(self):
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"""Returns true if this is a query"""
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return (self.flags & _FLAGS_QR_MASK) == _FLAGS_QR_QUERY
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def is_response(self):
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"""Returns true if this is a response"""
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return (self.flags & _FLAGS_QR_MASK) == _FLAGS_QR_RESPONSE
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def read_utf(self, offset, length):
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"""Reads a UTF-8 string of a given length from the packet"""
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return text_type(self.data[offset:offset + length], 'utf-8', 'replace')
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def read_name(self):
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"""Reads a domain name from the packet"""
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result = ''
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off = self.offset
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next_ = -1
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first = off
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while True:
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length = indexbytes(self.data, off)
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off += 1
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if length == 0:
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break
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t = length & 0xC0
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if t == 0x00:
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result = ''.join((result, self.read_utf(off, length) + '.'))
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off += length
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elif t == 0xC0:
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if next_ < 0:
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next_ = off + 1
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off = ((length & 0x3F) << 8) | indexbytes(self.data, off)
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if off >= first:
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raise IncomingDecodeError(
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"Bad domain name (circular) at %s" % (off,))
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first = off
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else:
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raise IncomingDecodeError("Bad domain name at %s" % (off,))
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if next_ >= 0:
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self.offset = next_
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else:
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self.offset = off
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return result
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class DNSOutgoing(object):
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"""Object representation of an outgoing packet"""
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def __init__(self, flags):
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self.finished = False
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self.id = 0
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self.flags = flags
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self.names = {}
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self.data = []
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self.size = 12
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self.state = False
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self.questions = []
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self.answers = []
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def add_question(self, record):
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"""Adds a question"""
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self.questions.append(record)
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def pack(self, format_, value):
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self.data.append(struct.pack(format_, value))
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self.size += struct.calcsize(format_)
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def write_byte(self, value):
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"""Writes a single byte to the packet"""
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self.pack(b'!c', int2byte(value))
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def insert_short(self, index, value):
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"""Inserts an unsigned short in a certain position in the packet"""
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self.data.insert(index, struct.pack(b'!H', value))
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self.size += 2
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def write_short(self, value):
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"""Writes an unsigned short to the packet"""
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self.pack(b'!H', value)
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def write_int(self, value):
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"""Writes an unsigned integer to the packet"""
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self.pack(b'!I', int(value))
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def write_string(self, value):
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"""Writes a string to the packet"""
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assert isinstance(value, bytes)
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self.data.append(value)
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self.size += len(value)
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def write_utf(self, s):
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"""Writes a UTF-8 string of a given length to the packet"""
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utfstr = s.encode('utf-8')
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length = len(utfstr)
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self.write_byte(length)
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self.write_string(utfstr)
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def write_character_string(self, value):
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assert isinstance(value, bytes)
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length = len(value)
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self.write_byte(length)
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self.write_string(value)
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def write_name(self, name):
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# split name into each label
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parts = name.split('.')
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if not parts[-1]:
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parts.pop()
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# construct each suffix
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name_suffices = ['.'.join(parts[i:]) for i in range(len(parts))]
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# look for an existing name or suffix
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for count, sub_name in enumerate(name_suffices):
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if sub_name in self.names:
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break
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else:
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count = len(name_suffices)
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# note the new names we are saving into the packet
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name_length = len(name.encode('utf-8'))
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for suffix in name_suffices[:count]:
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self.names[suffix] = self.size + name_length - len(suffix.encode('utf-8')) - 1
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# write the new names out.
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for part in parts[:count]:
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self.write_utf(part)
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# if we wrote part of the name, create a pointer to the rest
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if count != len(name_suffices):
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# Found substring in packet, create pointer
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index = self.names[name_suffices[count]]
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self.write_byte((index >> 8) | 0xC0)
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self.write_byte(index & 0xFF)
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else:
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# this is the end of a name
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self.write_byte(0)
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def write_question(self, question):
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self.write_name(question.name)
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self.write_short(question.type)
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self.write_short(question.class_)
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def packet(self):
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if not self.state:
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for question in self.questions:
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self.write_question(question)
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self.state = True
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self.insert_short(0, 0) # num additionals
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self.insert_short(0, 0) # num authorities
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self.insert_short(0, 0) # num answers
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self.insert_short(0, len(self.questions))
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self.insert_short(0, self.flags) # _FLAGS_QR_QUERY
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self.insert_short(0, 0)
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return b''.join(self.data)
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class Engine(threading.Thread):
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def __init__(self, zc):
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threading.Thread.__init__(self, name='zeroconf-Engine')
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self.daemon = True
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self.zc = zc
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self.readers = {}
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self.timeout = 5
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self.condition = threading.Condition()
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self.start()
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def run(self):
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while not self.zc.done:
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# pylint: disable=len-as-condition
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with self.condition:
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rs = self.readers.keys()
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if len(rs) == 0:
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# No sockets to manage, but we wait for the timeout
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# or addition of a socket
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self.condition.wait(self.timeout)
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if len(rs) != 0:
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try:
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rr, _, _ = select.select(rs, [], [], self.timeout)
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if not self.zc.done:
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for socket_ in rr:
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reader = self.readers.get(socket_)
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if reader:
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reader.handle_read(socket_)
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except (select.error, socket.error) as e:
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# If the socket was closed by another thread, during
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# shutdown, ignore it and exit
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if e.args[0] != socket.EBADF or not self.zc.done:
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raise
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def add_reader(self, reader, socket_):
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with self.condition:
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self.readers[socket_] = reader
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self.condition.notify()
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def del_reader(self, socket_):
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with self.condition:
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del self.readers[socket_]
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self.condition.notify()
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class Listener(QuietLogger):
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def __init__(self, zc):
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self.zc = zc
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self.data = None
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def handle_read(self, socket_):
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try:
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data, (addr, port) = socket_.recvfrom(_MAX_MSG_ABSOLUTE)
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except Exception: # pylint: disable=broad-except
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self.log_exception_warning()
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return
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log.debug('Received from %r:%r: %r ', addr, port, data)
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self.data = data
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msg = DNSIncoming(data)
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if not msg.valid or msg.is_query():
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pass
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else:
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self.zc.handle_response(msg)
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class RecordUpdateListener(object):
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def update_record(self, zc, now, record):
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raise NotImplementedError()
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class HostResolver(RecordUpdateListener):
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def __init__(self, name):
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self.name = name
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self.address = None
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def update_record(self, zc, now, record):
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if record is None:
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return
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if record.type == _TYPE_A:
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assert isinstance(record, DNSAddress)
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if record.name == self.name:
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self.address = record.address
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def request(self, zc, timeout):
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now = time.time()
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delay = 0.2
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next_ = now + delay
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last = now + timeout
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try:
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zc.add_listener(self)
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while self.address is None:
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if last <= now:
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# Timeout
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return False
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if next_ <= now:
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out = DNSOutgoing(_FLAGS_QR_QUERY)
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out.add_question(
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DNSQuestion(self.name, _TYPE_A, _CLASS_IN))
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zc.send(out)
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next_ = now + delay
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delay *= 2
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zc.wait(min(next_, last) - now)
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now = time.time()
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finally:
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zc.remove_listener(self)
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return True
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class DashboardStatus(RecordUpdateListener, threading.Thread):
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def __init__(self, zc, on_update):
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threading.Thread.__init__(self)
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self.zc = zc
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self.query_hosts = set()
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self.key_to_host = {}
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self.cache = {}
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self.stop_event = threading.Event()
|
|
self.query_event = threading.Event()
|
|
self.on_update = on_update
|
|
|
|
def update_record(self, zc, now, record):
|
|
if record is None:
|
|
return
|
|
if record.type in (_TYPE_A, _TYPE_AAAA, _TYPE_TXT):
|
|
assert isinstance(record, DNSEntry)
|
|
if record.name in self.query_hosts:
|
|
self.cache.setdefault(record.name, []).insert(0, record)
|
|
self.purge_cache()
|
|
|
|
def purge_cache(self):
|
|
new_cache = {}
|
|
for host, records in self.cache.items():
|
|
if host not in self.query_hosts:
|
|
continue
|
|
new_records = [rec for rec in records if not rec.is_removable(time.time())]
|
|
if new_records:
|
|
new_cache[host] = new_records
|
|
self.cache = new_cache
|
|
self.on_update({key: self.host_status(key) for key in self.key_to_host})
|
|
|
|
def request_query(self, hosts):
|
|
self.query_hosts = set(host for host in hosts.values())
|
|
self.key_to_host = hosts
|
|
self.query_event.set()
|
|
|
|
def stop(self):
|
|
self.stop_event.set()
|
|
self.query_event.set()
|
|
|
|
def host_status(self, key):
|
|
return self.key_to_host.get(key) in self.cache
|
|
|
|
def run(self):
|
|
self.zc.add_listener(self)
|
|
while not self.stop_event.is_set():
|
|
self.purge_cache()
|
|
for host in self.query_hosts:
|
|
if all(record.is_expired(time.time()) for record in self.cache.get(host, [])):
|
|
out = DNSOutgoing(_FLAGS_QR_QUERY)
|
|
out.add_question(
|
|
DNSQuestion(host, _TYPE_A, _CLASS_IN))
|
|
self.zc.send(out)
|
|
self.query_event.wait()
|
|
self.query_event.clear()
|
|
self.zc.remove_listener(self)
|
|
|
|
|
|
def get_all_addresses():
|
|
return list(set(
|
|
addr.ip
|
|
for iface in ifaddr.get_adapters()
|
|
for addr in iface.ips
|
|
if addr.is_IPv4 and addr.network_prefix != 32 # Host only netmask 255.255.255.255
|
|
))
|
|
|
|
|
|
def new_socket():
|
|
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
|
|
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
|
|
|
|
# SO_REUSEADDR should be equivalent to SO_REUSEPORT for
|
|
# multicast UDP sockets (p 731, "TCP/IP Illustrated,
|
|
# Volume 2"), but some BSD-derived systems require
|
|
# SO_REUSEPORT to be specified explicitly. Also, not all
|
|
# versions of Python have SO_REUSEPORT available.
|
|
# Catch OSError and socket.error for kernel versions <3.9 because lacking
|
|
# SO_REUSEPORT support.
|
|
try:
|
|
reuseport = socket.SO_REUSEPORT
|
|
except AttributeError:
|
|
pass
|
|
else:
|
|
try:
|
|
s.setsockopt(socket.SOL_SOCKET, reuseport, 1)
|
|
except (OSError, socket.error) as err:
|
|
# OSError on python 3, socket.error on python 2
|
|
if err.errno != errno.ENOPROTOOPT:
|
|
raise
|
|
|
|
# OpenBSD needs the ttl and loop values for the IP_MULTICAST_TTL and
|
|
# IP_MULTICAST_LOOP socket options as an unsigned char.
|
|
ttl = struct.pack(b'B', 255)
|
|
s.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, ttl)
|
|
loop = struct.pack(b'B', 1)
|
|
s.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_LOOP, loop)
|
|
|
|
s.bind(('', _MDNS_PORT))
|
|
return s
|
|
|
|
|
|
class Zeroconf(QuietLogger):
|
|
def __init__(self):
|
|
# hook for threads
|
|
self._GLOBAL_DONE = False
|
|
|
|
self._listen_socket = new_socket()
|
|
interfaces = get_all_addresses()
|
|
|
|
self._respond_sockets = []
|
|
|
|
for i in interfaces:
|
|
try:
|
|
_value = socket.inet_aton(_MDNS_ADDR) + socket.inet_aton(i)
|
|
self._listen_socket.setsockopt(
|
|
socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, _value)
|
|
except socket.error as e:
|
|
_errno = e.args[0]
|
|
if _errno == errno.EADDRINUSE:
|
|
log.info(
|
|
'Address in use when adding %s to multicast group, '
|
|
'it is expected to happen on some systems', i,
|
|
)
|
|
elif _errno == errno.EADDRNOTAVAIL:
|
|
log.info(
|
|
'Address not available when adding %s to multicast '
|
|
'group, it is expected to happen on some systems', i,
|
|
)
|
|
continue
|
|
elif _errno == errno.EINVAL:
|
|
log.info(
|
|
'Interface of %s does not support multicast, '
|
|
'it is expected in WSL', i
|
|
)
|
|
continue
|
|
|
|
else:
|
|
raise
|
|
|
|
respond_socket = new_socket()
|
|
respond_socket.setsockopt(
|
|
socket.IPPROTO_IP, socket.IP_MULTICAST_IF, socket.inet_aton(i))
|
|
|
|
self._respond_sockets.append(respond_socket)
|
|
|
|
self.listeners = []
|
|
|
|
self.condition = threading.Condition()
|
|
|
|
self.engine = Engine(self)
|
|
self.listener = Listener(self)
|
|
self.engine.add_reader(self.listener, self._listen_socket)
|
|
|
|
@property
|
|
def done(self):
|
|
return self._GLOBAL_DONE
|
|
|
|
def wait(self, timeout):
|
|
"""Calling thread waits for a given number of milliseconds or
|
|
until notified."""
|
|
with self.condition:
|
|
self.condition.wait(timeout)
|
|
|
|
def notify_all(self):
|
|
"""Notifies all waiting threads"""
|
|
with self.condition:
|
|
self.condition.notify_all()
|
|
|
|
def resolve_host(self, host, timeout=3.0):
|
|
info = HostResolver(host)
|
|
if info.request(self, timeout):
|
|
return socket.inet_ntoa(info.address)
|
|
return None
|
|
|
|
def add_listener(self, listener):
|
|
self.listeners.append(listener)
|
|
self.notify_all()
|
|
|
|
def remove_listener(self, listener):
|
|
"""Removes a listener."""
|
|
try:
|
|
self.listeners.remove(listener)
|
|
self.notify_all()
|
|
except Exception as e: # pylint: disable=broad-except
|
|
log.exception('Unknown error, possibly benign: %r', e)
|
|
|
|
def update_record(self, now, rec):
|
|
"""Used to notify listeners of new information that has updated
|
|
a record."""
|
|
for listener in self.listeners:
|
|
listener.update_record(self, now, rec)
|
|
self.notify_all()
|
|
|
|
def handle_response(self, msg):
|
|
"""Deal with incoming response packets. All answers
|
|
are held in the cache, and listeners are notified."""
|
|
now = time.time()
|
|
for record in msg.answers:
|
|
self.update_record(now, record)
|
|
|
|
def send(self, out):
|
|
"""Sends an outgoing packet."""
|
|
packet = out.packet()
|
|
log.debug('Sending %r (%d bytes) as %r...', out, len(packet), packet)
|
|
for s in self._respond_sockets:
|
|
if self._GLOBAL_DONE:
|
|
return
|
|
try:
|
|
bytes_sent = s.sendto(packet, 0, (_MDNS_ADDR, _MDNS_PORT))
|
|
except Exception: # pylint: disable=broad-except
|
|
# on send errors, log the exception and keep going
|
|
self.log_exception_warning()
|
|
else:
|
|
if bytes_sent != len(packet):
|
|
self.log_warning_once(
|
|
'!!! sent %d out of %d bytes to %r' % (
|
|
bytes_sent, len(packet), s))
|
|
|
|
def close(self):
|
|
"""Ends the background threads, and prevent this instance from
|
|
servicing further queries."""
|
|
if not self._GLOBAL_DONE:
|
|
self._GLOBAL_DONE = True
|
|
# shutdown recv socket and thread
|
|
self.engine.del_reader(self._listen_socket)
|
|
self._listen_socket.close()
|
|
self.engine.join()
|
|
|
|
# shutdown the rest
|
|
self.notify_all()
|
|
for s in self._respond_sockets:
|
|
s.close()
|