Move to use zeroconf library instead of inline copy (#2192)

This commit is contained in:
Jesse Hills 2021-09-06 08:22:15 +12:00 committed by GitHub
parent 77508f7e44
commit ca12b8aa56
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GPG Key ID: 4AEE18F83AFDEB23
3 changed files with 53 additions and 727 deletions

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@ -41,7 +41,7 @@ from .util import password_hash
# pylint: disable=unused-import, wrong-import-order # pylint: disable=unused-import, wrong-import-order
from typing import Optional # noqa from typing import Optional # noqa
from esphome.zeroconf import DashboardStatus, Zeroconf from esphome.zeroconf import DashboardStatus, EsphomeZeroconf
_LOGGER = logging.getLogger(__name__) _LOGGER = logging.getLogger(__name__)
@ -501,7 +501,7 @@ def _ping_func(filename, address):
class MDNSStatusThread(threading.Thread): class MDNSStatusThread(threading.Thread):
def run(self): def run(self):
zc = Zeroconf() zc = EsphomeZeroconf()
def on_update(dat): def on_update(dat):
for key, b in dat.items(): for key, b in dat.items():

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@ -97,10 +97,10 @@ def is_ip_address(host):
def _resolve_with_zeroconf(host): def _resolve_with_zeroconf(host):
from esphome.core import EsphomeError from esphome.core import EsphomeError
from esphome.zeroconf import Zeroconf from esphome.zeroconf import EsphomeZeroconf
try: try:
zc = Zeroconf() zc = EsphomeZeroconf()
except Exception as err: except Exception as err:
raise EsphomeError( raise EsphomeError(
"Cannot start mDNS sockets, is this a docker container without " "Cannot start mDNS sockets, is this a docker container without "

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@ -1,520 +1,27 @@
# Custom zeroconf implementation based on python-zeroconf
# (https://github.com/jstasiak/python-zeroconf) that supports Python 2
import errno
import logging
import select
import socket import socket
import struct
import sys
import threading import threading
import time import time
from typing import Optional
import ifaddr from zeroconf import (
_CLASS_IN,
log = logging.getLogger(__name__) _FLAGS_QR_QUERY,
_TYPE_A,
# Some timing constants DNSAddress,
DNSOutgoing,
_LISTENER_TIME = 200 DNSRecord,
DNSQuestion,
# Some DNS constants RecordUpdateListener,
Zeroconf,
_MDNS_ADDR = "224.0.0.251"
_MDNS_PORT = 5353
_MAX_MSG_ABSOLUTE = 8966
_FLAGS_QR_MASK = 0x8000 # query response mask
_FLAGS_QR_QUERY = 0x0000 # query
_FLAGS_QR_RESPONSE = 0x8000 # response
_FLAGS_AA = 0x0400 # Authoritative answer
_FLAGS_TC = 0x0200 # Truncated
_FLAGS_RD = 0x0100 # Recursion desired
_FLAGS_RA = 0x8000 # Recursion available
_FLAGS_Z = 0x0040 # Zero
_FLAGS_AD = 0x0020 # Authentic data
_FLAGS_CD = 0x0010 # Checking disabled
_CLASS_IN = 1
_CLASS_CS = 2
_CLASS_CH = 3
_CLASS_HS = 4
_CLASS_NONE = 254
_CLASS_ANY = 255
_CLASS_MASK = 0x7FFF
_CLASS_UNIQUE = 0x8000
_TYPE_A = 1
_TYPE_NS = 2
_TYPE_MD = 3
_TYPE_MF = 4
_TYPE_CNAME = 5
_TYPE_SOA = 6
_TYPE_MB = 7
_TYPE_MG = 8
_TYPE_MR = 9
_TYPE_NULL = 10
_TYPE_WKS = 11
_TYPE_PTR = 12
_TYPE_HINFO = 13
_TYPE_MINFO = 14
_TYPE_MX = 15
_TYPE_TXT = 16
_TYPE_AAAA = 28
_TYPE_SRV = 33
_TYPE_ANY = 255
# Mapping constants to names
int2byte = struct.Struct(">B").pack
# Exceptions
class Error(Exception):
pass
class IncomingDecodeError(Error):
pass
# pylint: disable=no-init
class QuietLogger:
_seen_logs = {}
@classmethod
def log_exception_warning(cls, logger_data=None):
exc_info = sys.exc_info()
exc_str = str(exc_info[1])
if exc_str not in cls._seen_logs:
# log at warning level the first time this is seen
cls._seen_logs[exc_str] = exc_info
logger = log.warning
else:
logger = log.debug
if logger_data is not None:
logger(*logger_data)
logger("Exception occurred:", exc_info=True)
@classmethod
def log_warning_once(cls, *args):
msg_str = args[0]
if msg_str not in cls._seen_logs:
cls._seen_logs[msg_str] = 0
logger = log.warning
else:
logger = log.debug
cls._seen_logs[msg_str] += 1
logger(*args)
class DNSEntry:
"""A DNS entry"""
def __init__(self, name, type_, class_):
self.key = name.lower()
self.name = name
self.type = type_
self.class_ = class_ & _CLASS_MASK
self.unique = (class_ & _CLASS_UNIQUE) != 0
class DNSQuestion(DNSEntry):
"""A DNS question entry"""
def __init__(self, name, type_, class_):
DNSEntry.__init__(self, name, type_, class_)
def answered_by(self, rec):
"""Returns true if the question is answered by the record"""
return (
self.class_ == rec.class_
and (self.type == rec.type or self.type == _TYPE_ANY)
and self.name == rec.name
) )
class DNSRecord(DNSEntry):
"""A DNS record - like a DNS entry, but has a TTL"""
def __init__(self, name, type_, class_, ttl):
DNSEntry.__init__(self, name, type_, class_)
self.ttl = 15
self.created = time.time()
def write(self, out):
"""Abstract method"""
raise NotImplementedError
def is_expired(self, now):
return self.created + self.ttl <= now
def is_removable(self, now):
return self.created + self.ttl * 2 <= now
class DNSAddress(DNSRecord):
"""A DNS address record"""
def __init__(self, name, type_, class_, ttl, address):
DNSRecord.__init__(self, name, type_, class_, ttl)
self.address = address
def write(self, out):
"""Used in constructing an outgoing packet"""
out.write_string(self.address)
class DNSText(DNSRecord):
"""A DNS text record"""
def __init__(self, name, type_, class_, ttl, text):
assert isinstance(text, (bytes, type(None)))
DNSRecord.__init__(self, name, type_, class_, ttl)
self.text = text
def write(self, out):
"""Used in constructing an outgoing packet"""
out.write_string(self.text)
class DNSIncoming(QuietLogger):
"""Object representation of an incoming DNS packet"""
def __init__(self, data):
"""Constructor from string holding bytes of packet"""
self.offset = 0
self.data = data
self.questions = []
self.answers = []
self.id = 0
self.flags = 0 # type: int
self.num_questions = 0
self.num_answers = 0
self.num_authorities = 0
self.num_additionals = 0
self.valid = False
try:
self.read_header()
self.read_questions()
self.read_others()
self.valid = True
except (IndexError, struct.error, IncomingDecodeError):
self.log_exception_warning(
("Choked at offset %d while unpacking %r", self.offset, data)
)
def unpack(self, format_):
length = struct.calcsize(format_)
info = struct.unpack(format_, self.data[self.offset : self.offset + length])
self.offset += length
return info
def read_header(self):
"""Reads header portion of packet"""
(
self.id,
self.flags,
self.num_questions,
self.num_answers,
self.num_authorities,
self.num_additionals,
) = self.unpack(b"!6H")
def read_questions(self):
"""Reads questions section of packet"""
for _ in range(self.num_questions):
name = self.read_name()
type_, class_ = self.unpack(b"!HH")
question = DNSQuestion(name, type_, class_)
self.questions.append(question)
def read_character_string(self):
"""Reads a character string from the packet"""
length = self.data[self.offset]
self.offset += 1
return self.read_string(length)
def read_string(self, length):
"""Reads a string of a given length from the packet"""
info = self.data[self.offset : self.offset + length]
self.offset += length
return info
def read_unsigned_short(self):
"""Reads an unsigned short from the packet"""
return self.unpack(b"!H")[0]
def read_others(self):
"""Reads the answers, authorities and additionals section of the
packet"""
n = self.num_answers + self.num_authorities + self.num_additionals
for _ in range(n):
domain = self.read_name()
type_, class_, ttl, length = self.unpack(b"!HHiH")
rec = None
if type_ == _TYPE_A:
rec = DNSAddress(domain, type_, class_, ttl, self.read_string(4))
elif type_ == _TYPE_TXT:
rec = DNSText(domain, type_, class_, ttl, self.read_string(length))
elif type_ == _TYPE_AAAA:
rec = DNSAddress(domain, type_, class_, ttl, self.read_string(16))
else:
# Try to ignore types we don't know about
# Skip the payload for the resource record so the next
# records can be parsed correctly
self.offset += length
if rec is not None:
self.answers.append(rec)
def is_query(self):
"""Returns true if this is a query"""
return (self.flags & _FLAGS_QR_MASK) == _FLAGS_QR_QUERY
def is_response(self):
"""Returns true if this is a response"""
return (self.flags & _FLAGS_QR_MASK) == _FLAGS_QR_RESPONSE
def read_utf(self, offset, length):
"""Reads a UTF-8 string of a given length from the packet"""
return str(self.data[offset : offset + length], "utf-8", "replace")
def read_name(self):
"""Reads a domain name from the packet"""
result = ""
off = self.offset
next_ = -1
first = off
while True:
length = self.data[off]
off += 1
if length == 0:
break
t = length & 0xC0
if t == 0x00:
result = "".join((result, self.read_utf(off, length) + "."))
off += length
elif t == 0xC0:
if next_ < 0:
next_ = off + 1
off = ((length & 0x3F) << 8) | self.data[off]
if off >= first:
raise IncomingDecodeError(f"Bad domain name (circular) at {off}")
first = off
else:
raise IncomingDecodeError(f"Bad domain name at {off}")
if next_ >= 0:
self.offset = next_
else:
self.offset = off
return result
class DNSOutgoing:
"""Object representation of an outgoing packet"""
def __init__(self, flags):
self.finished = False
self.id = 0
self.flags = flags
self.names = {}
self.data = []
self.size = 12
self.state = False
self.questions = []
self.answers = []
def add_question(self, record):
"""Adds a question"""
self.questions.append(record)
def pack(self, format_, value):
self.data.append(struct.pack(format_, value))
self.size += struct.calcsize(format_)
def write_byte(self, value):
"""Writes a single byte to the packet"""
self.pack(b"!c", int2byte(value))
def insert_short(self, index, value):
"""Inserts an unsigned short in a certain position in the packet"""
self.data.insert(index, struct.pack(b"!H", value))
self.size += 2
def write_short(self, value):
"""Writes an unsigned short to the packet"""
self.pack(b"!H", value)
def write_int(self, value):
"""Writes an unsigned integer to the packet"""
self.pack(b"!I", int(value))
def write_string(self, value):
"""Writes a string to the packet"""
assert isinstance(value, bytes)
self.data.append(value)
self.size += len(value)
def write_utf(self, s):
"""Writes a UTF-8 string of a given length to the packet"""
utfstr = s.encode("utf-8")
length = len(utfstr)
self.write_byte(length)
self.write_string(utfstr)
def write_character_string(self, value):
assert isinstance(value, bytes)
length = len(value)
self.write_byte(length)
self.write_string(value)
def write_name(self, name):
# split name into each label
parts = name.split(".")
if not parts[-1]:
parts.pop()
# construct each suffix
name_suffices = [".".join(parts[i:]) for i in range(len(parts))]
# look for an existing name or suffix
for count, sub_name in enumerate(name_suffices):
if sub_name in self.names:
break
else:
count = len(name_suffices)
# note the new names we are saving into the packet
name_length = len(name.encode("utf-8"))
for suffix in name_suffices[:count]:
self.names[suffix] = (
self.size + name_length - len(suffix.encode("utf-8")) - 1
)
# write the new names out.
for part in parts[:count]:
self.write_utf(part)
# if we wrote part of the name, create a pointer to the rest
if count != len(name_suffices):
# Found substring in packet, create pointer
index = self.names[name_suffices[count]]
self.write_byte((index >> 8) | 0xC0)
self.write_byte(index & 0xFF)
else:
# this is the end of a name
self.write_byte(0)
def write_question(self, question):
self.write_name(question.name)
self.write_short(question.type)
self.write_short(question.class_)
def packet(self):
if not self.state:
for question in self.questions:
self.write_question(question)
self.state = True
self.insert_short(0, 0) # num additionals
self.insert_short(0, 0) # num authorities
self.insert_short(0, 0) # num answers
self.insert_short(0, len(self.questions))
self.insert_short(0, self.flags) # _FLAGS_QR_QUERY
self.insert_short(0, 0)
return b"".join(self.data)
class Engine(threading.Thread):
def __init__(self, zc):
threading.Thread.__init__(self, name="zeroconf-Engine")
self.daemon = True
self.zc = zc
self.readers = {}
self.timeout = 5
self.condition = threading.Condition()
self.start()
def run(self):
while not self.zc.done:
# pylint: disable=len-as-condition
with self.condition:
rs = self.readers.keys()
if len(rs) == 0:
# No sockets to manage, but we wait for the timeout
# or addition of a socket
self.condition.wait(self.timeout)
if len(rs) != 0:
try:
rr, _, _ = select.select(rs, [], [], self.timeout)
if not self.zc.done:
for socket_ in rr:
reader = self.readers.get(socket_)
if reader:
reader.handle_read(socket_)
except OSError as e:
# If the socket was closed by another thread, during
# shutdown, ignore it and exit
if e.args[0] != socket.EBADF or not self.zc.done:
raise
def add_reader(self, reader, socket_):
with self.condition:
self.readers[socket_] = reader
self.condition.notify()
def del_reader(self, socket_):
with self.condition:
del self.readers[socket_]
self.condition.notify()
class Listener(QuietLogger):
def __init__(self, zc):
self.zc = zc
self.data = None
def handle_read(self, socket_):
try:
data, (addr, port) = socket_.recvfrom(_MAX_MSG_ABSOLUTE)
except Exception: # pylint: disable=broad-except
self.log_exception_warning()
return
log.debug("Received from %r:%r: %r ", addr, port, data)
self.data = data
msg = DNSIncoming(data)
if not msg.valid or msg.is_query():
pass
else:
self.zc.handle_response(msg)
class RecordUpdateListener:
def update_record(self, zc, now, record):
raise NotImplementedError()
class HostResolver(RecordUpdateListener): class HostResolver(RecordUpdateListener):
def __init__(self, name): def __init__(self, name: str):
self.name = name self.name = name
self.address = None self.address: Optional[bytes] = None
def update_record(self, zc, now, record): def update_record(self, zc: Zeroconf, now: float, record: DNSRecord) -> None:
if record is None: if record is None:
return return
if record.type == _TYPE_A: if record.type == _TYPE_A:
@ -522,14 +29,14 @@ class HostResolver(RecordUpdateListener):
if record.name == self.name: if record.name == self.name:
self.address = record.address self.address = record.address
def request(self, zc, timeout): def request(self, zc: Zeroconf, timeout: float) -> bool:
now = time.time() now = time.time()
delay = 0.2 delay = 0.2
next_ = now + delay next_ = now + delay
last = now + timeout last = now + timeout
try: try:
zc.add_listener(self) zc.add_listener(self, None)
while self.address is None: while self.address is None:
if last <= now: if last <= now:
# Timeout # Timeout
@ -550,56 +57,52 @@ class HostResolver(RecordUpdateListener):
class DashboardStatus(RecordUpdateListener, threading.Thread): class DashboardStatus(RecordUpdateListener, threading.Thread):
def __init__(self, zc, on_update): PING_AFTER = 15 * 1000 # Send new mDNS request after 15 seconds
OFFLINE_AFTER = PING_AFTER * 2 # Offline if no mDNS response after 30 seconds
def __init__(self, zc: Zeroconf, on_update) -> None:
threading.Thread.__init__(self) threading.Thread.__init__(self)
self.zc = zc self.zc = zc
self.query_hosts = set() self.query_hosts: set[str] = set()
self.key_to_host = {} self.key_to_host: dict[str, str] = {}
self.cache = {}
self.stop_event = threading.Event() self.stop_event = threading.Event()
self.query_event = threading.Event() self.query_event = threading.Event()
self.on_update = on_update self.on_update = on_update
def update_record(self, zc, now, record): def update_record(self, zc: Zeroconf, now: float, record: DNSRecord) -> None:
if record is None: pass
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): def request_query(self, hosts: dict[str, str]) -> None:
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(hosts.values()) self.query_hosts = set(hosts.values())
self.key_to_host = hosts self.key_to_host = hosts
self.query_event.set() self.query_event.set()
def stop(self): def stop(self) -> None:
self.stop_event.set() self.stop_event.set()
self.query_event.set() self.query_event.set()
def host_status(self, key): def host_status(self, key: str) -> bool:
return self.key_to_host.get(key) in self.cache entries = self.zc.cache.entries_with_name(key)
if not entries:
return False
now = time.time() * 1000
def run(self): return any(
self.zc.add_listener(self) (entry.created + DashboardStatus.OFFLINE_AFTER) >= now for entry in entries
)
def run(self) -> None:
self.zc.add_listener(self, None)
while not self.stop_event.is_set(): while not self.stop_event.is_set():
self.purge_cache() self.on_update(
{key: self.host_status(host) for key, host in self.key_to_host.items()}
)
now = time.time() * 1000
for host in self.query_hosts: for host in self.query_hosts:
if all( entries = self.zc.cache.entries_with_name(host)
record.is_expired(time.time()) if not entries or all(
for record in self.cache.get(host, []) (entry.created + DashboardStatus.PING_AFTER) <= now
for entry in entries
): ):
out = DNSOutgoing(_FLAGS_QR_QUERY) out = DNSOutgoing(_FLAGS_QR_QUERY)
out.add_question(DNSQuestion(host, _TYPE_A, _CLASS_IN)) out.add_question(DNSQuestion(host, _TYPE_A, _CLASS_IN))
@ -609,186 +112,9 @@ class DashboardStatus(RecordUpdateListener, threading.Thread):
self.zc.remove_listener(self) self.zc.remove_listener(self)
def get_all_addresses(): class EsphomeZeroconf(Zeroconf):
return list( def resolve_host(self, host: str, timeout=3.0):
{
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 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 OSError 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) info = HostResolver(host)
if info.request(self, timeout): if info.request(self, timeout):
return socket.inet_ntoa(info.address) return socket.inet_ntoa(info.address)
return None 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()