def connect(self,
loop,
metadata,
domain: str,
host,
port,
negotiation_timeout,
base_logger=None):
"""
.. seealso::
:meth:`BaseConnector.connect`
For general information on the :meth:`connect` method.
Connect to `host` at TCP port number `port`. The
:class:`aioxmpp.security_layer.SecurityLayer` object `metadata` is used
to determine the parameters of the TLS connection.
First, a normal TCP connection is opened and the stream header is sent.
The stream features are waited for, and then STARTTLS is negotiated if
possible.
:attr:`~.security_layer.SecurityLayer.tls_required` is honoured: if it
is true and TLS negotiation fails, :class:`~.errors.TLSUnavailable` is
raised. TLS negotiation is always attempted if
:attr:`~.security_layer.SecurityLayer.tls_required` is true, even if
the server does not advertise a STARTTLS stream feature. This might
help to prevent trivial downgrade attacks, and we don’t have anything
to lose at this point anymore anyways.
:attr:`~.security_layer.SecurityLayer.ssl_context_factory` and
:attr:`~.security_layer.SecurityLayer.certificate_verifier_factory` are
used to configure the TLS connection.
.. versionchanged:: 0.10
The `negotiation_timeout` is set as
:attr:`~.XMLStream.deadtime_hard_limit` on the returned XML stream.
"""
features_future = asyncio.Future(loop=loop)
stream = protocol.XMLStream(
to=domain,
features_future=features_future,
base_logger=base_logger,
)
if base_logger is not None:
logger = base_logger.getChild(type(self).__name__)
else:
logger = logging.getLogger(".".join([
__name__,
type(self).__qualname__,
]))
try:
transport, _ = yield from ssl_transport.create_starttls_connection(
loop,
lambda: stream,
host=host,
port=port,
peer_hostname=host,
server_hostname=domain,
use_starttls=True,
)
except: # NOQA
stream.abort()
raise
stream.deadtime_hard_limit = timedelta(seconds=negotiation_timeout)
features = yield from features_future
try:
features[nonza.StartTLSFeature]
except KeyError:
if not metadata.tls_required:
return transport, stream, (yield from features_future)
logger.debug(
"attempting STARTTLS despite not announced since it is"
" required")
try:
response = yield from protocol.send_and_wait_for(
stream, [
nonza.StartTLS(),
], [
nonza.StartTLSFailure,
nonza.StartTLSProceed,
])
except errors.StreamError as exc:
raise errors.TLSUnavailable(
"STARTTLS not supported by server, but required by client")
if not isinstance(response, nonza.StartTLSProceed):
if metadata.tls_required:
message = ("server failed to STARTTLS")
protocol.send_stream_error_and_close(
stream,
condition=errors.StreamErrorCondition.POLICY_VIOLATION,
text=message,
)
raise errors.TLSUnavailable(message)
return transport, stream, (yield from features_future)
verifier = metadata.certificate_verifier_factory()
yield from verifier.pre_handshake(
domain,
host,
port,
metadata,
)
ssl_context = metadata.ssl_context_factory()
verifier.setup_context(ssl_context, transport)
yield from stream.starttls(
ssl_context=ssl_context,
post_handshake_callback=verifier.post_handshake,
)
features_future = yield from protocol.reset_stream_and_get_features(
stream,
timeout=negotiation_timeout,
)
return transport, stream, features_future
def connect(self, loop, metadata, domain, host, port, negotiation_timeout):
"""
.. seealso::
:meth:`BaseConnector.connect`
For general information on the :meth:`connect` method.
Connect to `host` at TCP port number `port`. The
:class:`aioxmpp.security_layer.SecurityLayer` object `metadata` is used
to determine the parameters of the TLS connection.
First, a normal TCP connection is opened and the stream header is sent.
The stream features are waited for, and then STARTTLS is negotiated if
possible.
:attr:`~.security_layer.SecurityLayer.tls_required` is honoured: if it
is true and the server does not offer TLS or TLS negotiation fails,
:class:`~.errors.TLSUnavailable` is raised.
:attr:`~.security_layer.SecurityLayer.ssl_context_factory` and
:attr:`~.security_layer.SecurityLayer.certificate_verifier_factory` are
used to configure the TLS connection.
"""
features_future = asyncio.Future(loop=loop)
stream = protocol.XMLStream(
to=domain,
features_future=features_future,
)
transport, _ = yield from ssl_transport.create_starttls_connection(
loop,
lambda: stream,
host=host,
port=port,
peer_hostname=host,
server_hostname=domain,
use_starttls=True,
)
features = yield from features_future
try:
features[nonza.StartTLSFeature]
except KeyError:
if metadata.tls_required:
message = (
"STARTTLS not supported by server, but required by client")
protocol.send_stream_error_and_close(
stream,
condition=(namespaces.streams, "policy-violation"),
text=message,
)
raise errors.TLSUnavailable(message)
else:
return transport, stream, (yield from features_future)
response = yield from protocol.send_and_wait_for(
stream, [
nonza.StartTLS(),
], [
nonza.StartTLSFailure,
nonza.StartTLSProceed,
])
if not isinstance(response, nonza.StartTLSProceed):
if metadata.tls_required:
message = ("server failed to STARTTLS")
protocol.send_stream_error_and_close(
stream,
condition=(namespaces.streams, "policy-violation"),
text=message,
)
raise errors.TLSUnavailable(message)
return transport, stream, (yield from features_future)
verifier = metadata.certificate_verifier_factory()
yield from verifier.pre_handshake(
domain,
host,
port,
metadata,
)
ssl_context = metadata.ssl_context_factory()
verifier.setup_context(ssl_context, transport)
yield from stream.starttls(
ssl_context=ssl_context,
post_handshake_callback=verifier.post_handshake,
)
features_future = yield from protocol.reset_stream_and_get_features(
stream,
timeout=negotiation_timeout,
)
return transport, stream, features_future