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# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license | |
import socket | |
import ssl | |
import struct | |
import time | |
import aioquic.quic.configuration # type: ignore | |
import aioquic.quic.connection # type: ignore | |
import aioquic.quic.events # type: ignore | |
import trio | |
import dns.exception | |
import dns.inet | |
from dns._asyncbackend import NullContext | |
from dns.quic._common import ( | |
QUIC_MAX_DATAGRAM, | |
AsyncQuicConnection, | |
AsyncQuicManager, | |
BaseQuicStream, | |
UnexpectedEOF, | |
) | |
class TrioQuicStream(BaseQuicStream): | |
def __init__(self, connection, stream_id): | |
super().__init__(connection, stream_id) | |
self._wake_up = trio.Condition() | |
async def wait_for(self, amount): | |
while True: | |
if self._buffer.have(amount): | |
return | |
self._expecting = amount | |
async with self._wake_up: | |
await self._wake_up.wait() | |
self._expecting = 0 | |
async def receive(self, timeout=None): | |
if timeout is None: | |
context = NullContext(None) | |
else: | |
context = trio.move_on_after(timeout) | |
with context: | |
await self.wait_for(2) | |
(size,) = struct.unpack("!H", self._buffer.get(2)) | |
await self.wait_for(size) | |
return self._buffer.get(size) | |
raise dns.exception.Timeout | |
async def send(self, datagram, is_end=False): | |
data = self._encapsulate(datagram) | |
await self._connection.write(self._stream_id, data, is_end) | |
async def _add_input(self, data, is_end): | |
if self._common_add_input(data, is_end): | |
async with self._wake_up: | |
self._wake_up.notify() | |
async def close(self): | |
self._close() | |
# Streams are async context managers | |
async def __aenter__(self): | |
return self | |
async def __aexit__(self, exc_type, exc_val, exc_tb): | |
await self.close() | |
async with self._wake_up: | |
self._wake_up.notify() | |
return False | |
class TrioQuicConnection(AsyncQuicConnection): | |
def __init__(self, connection, address, port, source, source_port, manager=None): | |
super().__init__(connection, address, port, source, source_port, manager) | |
self._socket = trio.socket.socket(self._af, socket.SOCK_DGRAM, 0) | |
if self._source: | |
trio.socket.bind(dns.inet.low_level_address_tuple(self._source, self._af)) | |
self._handshake_complete = trio.Event() | |
self._run_done = trio.Event() | |
self._worker_scope = None | |
async def _worker(self): | |
try: | |
await self._socket.connect(self._peer) | |
while not self._done: | |
(expiration, interval) = self._get_timer_values(False) | |
with trio.CancelScope( | |
deadline=trio.current_time() + interval | |
) as self._worker_scope: | |
datagram = await self._socket.recv(QUIC_MAX_DATAGRAM) | |
self._connection.receive_datagram( | |
datagram, self._peer[0], time.time() | |
) | |
self._worker_scope = None | |
self._handle_timer(expiration) | |
datagrams = self._connection.datagrams_to_send(time.time()) | |
for datagram, _ in datagrams: | |
await self._socket.send(datagram) | |
await self._handle_events() | |
finally: | |
self._done = True | |
self._handshake_complete.set() | |
async def _handle_events(self): | |
count = 0 | |
while True: | |
event = self._connection.next_event() | |
if event is None: | |
return | |
if isinstance(event, aioquic.quic.events.StreamDataReceived): | |
stream = self._streams.get(event.stream_id) | |
if stream: | |
await stream._add_input(event.data, event.end_stream) | |
elif isinstance(event, aioquic.quic.events.HandshakeCompleted): | |
self._handshake_complete.set() | |
elif isinstance( | |
event, aioquic.quic.events.ConnectionTerminated | |
) or isinstance(event, aioquic.quic.events.StreamReset): | |
self._done = True | |
self._socket.close() | |
count += 1 | |
if count > 10: | |
# yield | |
count = 0 | |
await trio.sleep(0) | |
async def write(self, stream, data, is_end=False): | |
self._connection.send_stream_data(stream, data, is_end) | |
if self._worker_scope is not None: | |
self._worker_scope.cancel() | |
async def run(self): | |
if self._closed: | |
return | |
async with trio.open_nursery() as nursery: | |
nursery.start_soon(self._worker) | |
self._run_done.set() | |
async def make_stream(self, timeout=None): | |
if timeout is None: | |
context = NullContext(None) | |
else: | |
context = trio.move_on_after(timeout) | |
with context: | |
await self._handshake_complete.wait() | |
if self._done: | |
raise UnexpectedEOF | |
stream_id = self._connection.get_next_available_stream_id(False) | |
stream = TrioQuicStream(self, stream_id) | |
self._streams[stream_id] = stream | |
return stream | |
raise dns.exception.Timeout | |
async def close(self): | |
if not self._closed: | |
self._manager.closed(self._peer[0], self._peer[1]) | |
self._closed = True | |
self._connection.close() | |
if self._worker_scope is not None: | |
self._worker_scope.cancel() | |
await self._run_done.wait() | |
class TrioQuicManager(AsyncQuicManager): | |
def __init__( | |
self, nursery, conf=None, verify_mode=ssl.CERT_REQUIRED, server_name=None | |
): | |
super().__init__(conf, verify_mode, TrioQuicConnection, server_name) | |
self._nursery = nursery | |
def connect(self, address, port=853, source=None, source_port=0): | |
(connection, start) = self._connect(address, port, source, source_port) | |
if start: | |
self._nursery.start_soon(connection.run) | |
return connection | |
async def __aenter__(self): | |
return self | |
async def __aexit__(self, exc_type, exc_val, exc_tb): | |
# Copy the iterator into a list as exiting things will mutate the connections | |
# table. | |
connections = list(self._connections.values()) | |
for connection in connections: | |
await connection.close() | |
return False | |