diff options
Diffstat (limited to '.venv/lib/python3.12/site-packages/dns/quic/_common.py')
| -rw-r--r-- | .venv/lib/python3.12/site-packages/dns/quic/_common.py | 339 |
1 files changed, 339 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/dns/quic/_common.py b/.venv/lib/python3.12/site-packages/dns/quic/_common.py new file mode 100644 index 00000000..ce575b03 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/dns/quic/_common.py @@ -0,0 +1,339 @@ +# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license + +import base64 +import copy +import functools +import socket +import struct +import time +import urllib +from typing import Any, Optional + +import aioquic.h3.connection # type: ignore +import aioquic.h3.events # type: ignore +import aioquic.quic.configuration # type: ignore +import aioquic.quic.connection # type: ignore + +import dns.inet + +QUIC_MAX_DATAGRAM = 2048 +MAX_SESSION_TICKETS = 8 +# If we hit the max sessions limit we will delete this many of the oldest connections. +# The value must be a integer > 0 and <= MAX_SESSION_TICKETS. +SESSIONS_TO_DELETE = MAX_SESSION_TICKETS // 4 + + +class UnexpectedEOF(Exception): + pass + + +class Buffer: + def __init__(self): + self._buffer = b"" + self._seen_end = False + + def put(self, data, is_end): + if self._seen_end: + return + self._buffer += data + if is_end: + self._seen_end = True + + def have(self, amount): + if len(self._buffer) >= amount: + return True + if self._seen_end: + raise UnexpectedEOF + return False + + def seen_end(self): + return self._seen_end + + def get(self, amount): + assert self.have(amount) + data = self._buffer[:amount] + self._buffer = self._buffer[amount:] + return data + + def get_all(self): + assert self.seen_end() + data = self._buffer + self._buffer = b"" + return data + + +class BaseQuicStream: + def __init__(self, connection, stream_id): + self._connection = connection + self._stream_id = stream_id + self._buffer = Buffer() + self._expecting = 0 + self._headers = None + self._trailers = None + + def id(self): + return self._stream_id + + def headers(self): + return self._headers + + def trailers(self): + return self._trailers + + def _expiration_from_timeout(self, timeout): + if timeout is not None: + expiration = time.time() + timeout + else: + expiration = None + return expiration + + def _timeout_from_expiration(self, expiration): + if expiration is not None: + timeout = max(expiration - time.time(), 0.0) + else: + timeout = None + return timeout + + # Subclass must implement receive() as sync / async and which returns a message + # or raises. + + # Subclass must implement send() as sync / async and which takes a message and + # an EOF indicator. + + def send_h3(self, url, datagram, post=True): + if not self._connection.is_h3(): + raise SyntaxError("cannot send H3 to a non-H3 connection") + url_parts = urllib.parse.urlparse(url) + path = url_parts.path.encode() + if post: + method = b"POST" + else: + method = b"GET" + path += b"?dns=" + base64.urlsafe_b64encode(datagram).rstrip(b"=") + headers = [ + (b":method", method), + (b":scheme", url_parts.scheme.encode()), + (b":authority", url_parts.netloc.encode()), + (b":path", path), + (b"accept", b"application/dns-message"), + ] + if post: + headers.extend( + [ + (b"content-type", b"application/dns-message"), + (b"content-length", str(len(datagram)).encode()), + ] + ) + self._connection.send_headers(self._stream_id, headers, not post) + if post: + self._connection.send_data(self._stream_id, datagram, True) + + def _encapsulate(self, datagram): + if self._connection.is_h3(): + return datagram + l = len(datagram) + return struct.pack("!H", l) + datagram + + def _common_add_input(self, data, is_end): + self._buffer.put(data, is_end) + try: + return ( + self._expecting > 0 and self._buffer.have(self._expecting) + ) or self._buffer.seen_end + except UnexpectedEOF: + return True + + def _close(self): + self._connection.close_stream(self._stream_id) + self._buffer.put(b"", True) # send EOF in case we haven't seen it. + + +class BaseQuicConnection: + def __init__( + self, + connection, + address, + port, + source=None, + source_port=0, + manager=None, + ): + self._done = False + self._connection = connection + self._address = address + self._port = port + self._closed = False + self._manager = manager + self._streams = {} + if manager.is_h3(): + self._h3_conn = aioquic.h3.connection.H3Connection(connection, False) + else: + self._h3_conn = None + self._af = dns.inet.af_for_address(address) + self._peer = dns.inet.low_level_address_tuple((address, port)) + if source is None and source_port != 0: + if self._af == socket.AF_INET: + source = "0.0.0.0" + elif self._af == socket.AF_INET6: + source = "::" + else: + raise NotImplementedError + if source: + self._source = (source, source_port) + else: + self._source = None + + def is_h3(self): + return self._h3_conn is not None + + def close_stream(self, stream_id): + del self._streams[stream_id] + + def send_headers(self, stream_id, headers, is_end=False): + self._h3_conn.send_headers(stream_id, headers, is_end) + + def send_data(self, stream_id, data, is_end=False): + self._h3_conn.send_data(stream_id, data, is_end) + + def _get_timer_values(self, closed_is_special=True): + now = time.time() + expiration = self._connection.get_timer() + if expiration is None: + expiration = now + 3600 # arbitrary "big" value + interval = max(expiration - now, 0) + if self._closed and closed_is_special: + # lower sleep interval to avoid a race in the closing process + # which can lead to higher latency closing due to sleeping when + # we have events. + interval = min(interval, 0.05) + return (expiration, interval) + + def _handle_timer(self, expiration): + now = time.time() + if expiration <= now: + self._connection.handle_timer(now) + + +class AsyncQuicConnection(BaseQuicConnection): + async def make_stream(self, timeout: Optional[float] = None) -> Any: + pass + + +class BaseQuicManager: + def __init__( + self, conf, verify_mode, connection_factory, server_name=None, h3=False + ): + self._connections = {} + self._connection_factory = connection_factory + self._session_tickets = {} + self._tokens = {} + self._h3 = h3 + if conf is None: + verify_path = None + if isinstance(verify_mode, str): + verify_path = verify_mode + verify_mode = True + if h3: + alpn_protocols = ["h3"] + else: + alpn_protocols = ["doq", "doq-i03"] + conf = aioquic.quic.configuration.QuicConfiguration( + alpn_protocols=alpn_protocols, + verify_mode=verify_mode, + server_name=server_name, + ) + if verify_path is not None: + conf.load_verify_locations(verify_path) + self._conf = conf + + def _connect( + self, + address, + port=853, + source=None, + source_port=0, + want_session_ticket=True, + want_token=True, + ): + connection = self._connections.get((address, port)) + if connection is not None: + return (connection, False) + conf = self._conf + if want_session_ticket: + try: + session_ticket = self._session_tickets.pop((address, port)) + # We found a session ticket, so make a configuration that uses it. + conf = copy.copy(conf) + conf.session_ticket = session_ticket + except KeyError: + # No session ticket. + pass + # Whether or not we found a session ticket, we want a handler to save + # one. + session_ticket_handler = functools.partial( + self.save_session_ticket, address, port + ) + else: + session_ticket_handler = None + if want_token: + try: + token = self._tokens.pop((address, port)) + # We found a token, so make a configuration that uses it. + conf = copy.copy(conf) + conf.token = token + except KeyError: + # No token + pass + # Whether or not we found a token, we want a handler to save # one. + token_handler = functools.partial(self.save_token, address, port) + else: + token_handler = None + + qconn = aioquic.quic.connection.QuicConnection( + configuration=conf, + session_ticket_handler=session_ticket_handler, + token_handler=token_handler, + ) + lladdress = dns.inet.low_level_address_tuple((address, port)) + qconn.connect(lladdress, time.time()) + connection = self._connection_factory( + qconn, address, port, source, source_port, self + ) + self._connections[(address, port)] = connection + return (connection, True) + + def closed(self, address, port): + try: + del self._connections[(address, port)] + except KeyError: + pass + + def is_h3(self): + return self._h3 + + def save_session_ticket(self, address, port, ticket): + # We rely on dictionaries keys() being in insertion order here. We + # can't just popitem() as that would be LIFO which is the opposite of + # what we want. + l = len(self._session_tickets) + if l >= MAX_SESSION_TICKETS: + keys_to_delete = list(self._session_tickets.keys())[0:SESSIONS_TO_DELETE] + for key in keys_to_delete: + del self._session_tickets[key] + self._session_tickets[(address, port)] = ticket + + def save_token(self, address, port, token): + # We rely on dictionaries keys() being in insertion order here. We + # can't just popitem() as that would be LIFO which is the opposite of + # what we want. + l = len(self._tokens) + if l >= MAX_SESSION_TICKETS: + keys_to_delete = list(self._tokens.keys())[0:SESSIONS_TO_DELETE] + for key in keys_to_delete: + del self._tokens[key] + self._tokens[(address, port)] = token + + +class AsyncQuicManager(BaseQuicManager): + def connect(self, address, port=853, source=None, source_port=0): + raise NotImplementedError |