sieci/venv/lib/python3.7/site-packages/urllib3/connection.py
2020-01-31 06:49:32 +01:00

415 lines
14 KiB
Python

from __future__ import absolute_import
import datetime
import logging
import os
import socket
from socket import error as SocketError, timeout as SocketTimeout
import warnings
from .packages import six
from .packages.six.moves.http_client import HTTPConnection as _HTTPConnection
from .packages.six.moves.http_client import HTTPException # noqa: F401
try: # Compiled with SSL?
import ssl
BaseSSLError = ssl.SSLError
except (ImportError, AttributeError): # Platform-specific: No SSL.
ssl = None
class BaseSSLError(BaseException):
pass
try:
# Python 3: not a no-op, we're adding this to the namespace so it can be imported.
ConnectionError = ConnectionError
except NameError:
# Python 2
class ConnectionError(Exception):
pass
from .exceptions import (
NewConnectionError,
ConnectTimeoutError,
SubjectAltNameWarning,
SystemTimeWarning,
)
from .packages.ssl_match_hostname import match_hostname, CertificateError
from .util.ssl_ import (
resolve_cert_reqs,
resolve_ssl_version,
assert_fingerprint,
create_urllib3_context,
ssl_wrap_socket,
)
from .util import connection
from ._collections import HTTPHeaderDict
log = logging.getLogger(__name__)
port_by_scheme = {"http": 80, "https": 443}
# When it comes time to update this value as a part of regular maintenance
# (ie test_recent_date is failing) update it to ~6 months before the current date.
RECENT_DATE = datetime.date(2019, 1, 1)
class DummyConnection(object):
"""Used to detect a failed ConnectionCls import."""
pass
class HTTPConnection(_HTTPConnection, object):
"""
Based on httplib.HTTPConnection but provides an extra constructor
backwards-compatibility layer between older and newer Pythons.
Additional keyword parameters are used to configure attributes of the connection.
Accepted parameters include:
- ``strict``: See the documentation on :class:`urllib3.connectionpool.HTTPConnectionPool`
- ``source_address``: Set the source address for the current connection.
- ``socket_options``: Set specific options on the underlying socket. If not specified, then
defaults are loaded from ``HTTPConnection.default_socket_options`` which includes disabling
Nagle's algorithm (sets TCP_NODELAY to 1) unless the connection is behind a proxy.
For example, if you wish to enable TCP Keep Alive in addition to the defaults,
you might pass::
HTTPConnection.default_socket_options + [
(socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1),
]
Or you may want to disable the defaults by passing an empty list (e.g., ``[]``).
"""
default_port = port_by_scheme["http"]
#: Disable Nagle's algorithm by default.
#: ``[(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)]``
default_socket_options = [(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)]
#: Whether this connection verifies the host's certificate.
is_verified = False
def __init__(self, *args, **kw):
if not six.PY2:
kw.pop("strict", None)
# Pre-set source_address.
self.source_address = kw.get("source_address")
#: The socket options provided by the user. If no options are
#: provided, we use the default options.
self.socket_options = kw.pop("socket_options", self.default_socket_options)
_HTTPConnection.__init__(self, *args, **kw)
@property
def host(self):
"""
Getter method to remove any trailing dots that indicate the hostname is an FQDN.
In general, SSL certificates don't include the trailing dot indicating a
fully-qualified domain name, and thus, they don't validate properly when
checked against a domain name that includes the dot. In addition, some
servers may not expect to receive the trailing dot when provided.
However, the hostname with trailing dot is critical to DNS resolution; doing a
lookup with the trailing dot will properly only resolve the appropriate FQDN,
whereas a lookup without a trailing dot will search the system's search domain
list. Thus, it's important to keep the original host around for use only in
those cases where it's appropriate (i.e., when doing DNS lookup to establish the
actual TCP connection across which we're going to send HTTP requests).
"""
return self._dns_host.rstrip(".")
@host.setter
def host(self, value):
"""
Setter for the `host` property.
We assume that only urllib3 uses the _dns_host attribute; httplib itself
only uses `host`, and it seems reasonable that other libraries follow suit.
"""
self._dns_host = value
def _new_conn(self):
""" Establish a socket connection and set nodelay settings on it.
:return: New socket connection.
"""
extra_kw = {}
if self.source_address:
extra_kw["source_address"] = self.source_address
if self.socket_options:
extra_kw["socket_options"] = self.socket_options
try:
conn = connection.create_connection(
(self._dns_host, self.port), self.timeout, **extra_kw
)
except SocketTimeout:
raise ConnectTimeoutError(
self,
"Connection to %s timed out. (connect timeout=%s)"
% (self.host, self.timeout),
)
except SocketError as e:
raise NewConnectionError(
self, "Failed to establish a new connection: %s" % e
)
return conn
def _prepare_conn(self, conn):
self.sock = conn
# Google App Engine's httplib does not define _tunnel_host
if getattr(self, "_tunnel_host", None):
# TODO: Fix tunnel so it doesn't depend on self.sock state.
self._tunnel()
# Mark this connection as not reusable
self.auto_open = 0
def connect(self):
conn = self._new_conn()
self._prepare_conn(conn)
def request_chunked(self, method, url, body=None, headers=None):
"""
Alternative to the common request method, which sends the
body with chunked encoding and not as one block
"""
headers = HTTPHeaderDict(headers if headers is not None else {})
skip_accept_encoding = "accept-encoding" in headers
skip_host = "host" in headers
self.putrequest(
method, url, skip_accept_encoding=skip_accept_encoding, skip_host=skip_host
)
for header, value in headers.items():
self.putheader(header, value)
if "transfer-encoding" not in headers:
self.putheader("Transfer-Encoding", "chunked")
self.endheaders()
if body is not None:
stringish_types = six.string_types + (bytes,)
if isinstance(body, stringish_types):
body = (body,)
for chunk in body:
if not chunk:
continue
if not isinstance(chunk, bytes):
chunk = chunk.encode("utf8")
len_str = hex(len(chunk))[2:]
self.send(len_str.encode("utf-8"))
self.send(b"\r\n")
self.send(chunk)
self.send(b"\r\n")
# After the if clause, to always have a closed body
self.send(b"0\r\n\r\n")
class HTTPSConnection(HTTPConnection):
default_port = port_by_scheme["https"]
ssl_version = None
def __init__(
self,
host,
port=None,
key_file=None,
cert_file=None,
key_password=None,
strict=None,
timeout=socket._GLOBAL_DEFAULT_TIMEOUT,
ssl_context=None,
server_hostname=None,
**kw
):
HTTPConnection.__init__(self, host, port, strict=strict, timeout=timeout, **kw)
self.key_file = key_file
self.cert_file = cert_file
self.key_password = key_password
self.ssl_context = ssl_context
self.server_hostname = server_hostname
# Required property for Google AppEngine 1.9.0 which otherwise causes
# HTTPS requests to go out as HTTP. (See Issue #356)
self._protocol = "https"
class VerifiedHTTPSConnection(HTTPSConnection):
"""
Based on httplib.HTTPSConnection but wraps the socket with
SSL certification.
"""
cert_reqs = None
ca_certs = None
ca_cert_dir = None
ssl_version = None
assert_fingerprint = None
def set_cert(
self,
key_file=None,
cert_file=None,
cert_reqs=None,
key_password=None,
ca_certs=None,
assert_hostname=None,
assert_fingerprint=None,
ca_cert_dir=None,
):
"""
This method should only be called once, before the connection is used.
"""
# If cert_reqs is not provided we'll assume CERT_REQUIRED unless we also
# have an SSLContext object in which case we'll use its verify_mode.
if cert_reqs is None:
if self.ssl_context is not None:
cert_reqs = self.ssl_context.verify_mode
else:
cert_reqs = resolve_cert_reqs(None)
self.key_file = key_file
self.cert_file = cert_file
self.cert_reqs = cert_reqs
self.key_password = key_password
self.assert_hostname = assert_hostname
self.assert_fingerprint = assert_fingerprint
self.ca_certs = ca_certs and os.path.expanduser(ca_certs)
self.ca_cert_dir = ca_cert_dir and os.path.expanduser(ca_cert_dir)
def connect(self):
# Add certificate verification
conn = self._new_conn()
hostname = self.host
# Google App Engine's httplib does not define _tunnel_host
if getattr(self, "_tunnel_host", None):
self.sock = conn
# Calls self._set_hostport(), so self.host is
# self._tunnel_host below.
self._tunnel()
# Mark this connection as not reusable
self.auto_open = 0
# Override the host with the one we're requesting data from.
hostname = self._tunnel_host
server_hostname = hostname
if self.server_hostname is not None:
server_hostname = self.server_hostname
is_time_off = datetime.date.today() < RECENT_DATE
if is_time_off:
warnings.warn(
(
"System time is way off (before {0}). This will probably "
"lead to SSL verification errors"
).format(RECENT_DATE),
SystemTimeWarning,
)
# Wrap socket using verification with the root certs in
# trusted_root_certs
default_ssl_context = False
if self.ssl_context is None:
default_ssl_context = True
self.ssl_context = create_urllib3_context(
ssl_version=resolve_ssl_version(self.ssl_version),
cert_reqs=resolve_cert_reqs(self.cert_reqs),
)
context = self.ssl_context
context.verify_mode = resolve_cert_reqs(self.cert_reqs)
# Try to load OS default certs if none are given.
# Works well on Windows (requires Python3.4+)
if (
not self.ca_certs
and not self.ca_cert_dir
and default_ssl_context
and hasattr(context, "load_default_certs")
):
context.load_default_certs()
self.sock = ssl_wrap_socket(
sock=conn,
keyfile=self.key_file,
certfile=self.cert_file,
key_password=self.key_password,
ca_certs=self.ca_certs,
ca_cert_dir=self.ca_cert_dir,
server_hostname=server_hostname,
ssl_context=context,
)
if self.assert_fingerprint:
assert_fingerprint(
self.sock.getpeercert(binary_form=True), self.assert_fingerprint
)
elif (
context.verify_mode != ssl.CERT_NONE
and not getattr(context, "check_hostname", False)
and self.assert_hostname is not False
):
# While urllib3 attempts to always turn off hostname matching from
# the TLS library, this cannot always be done. So we check whether
# the TLS Library still thinks it's matching hostnames.
cert = self.sock.getpeercert()
if not cert.get("subjectAltName", ()):
warnings.warn(
(
"Certificate for {0} has no `subjectAltName`, falling back to check for a "
"`commonName` for now. This feature is being removed by major browsers and "
"deprecated by RFC 2818. (See https://github.com/urllib3/urllib3/issues/497 "
"for details.)".format(hostname)
),
SubjectAltNameWarning,
)
_match_hostname(cert, self.assert_hostname or server_hostname)
self.is_verified = (
context.verify_mode == ssl.CERT_REQUIRED
or self.assert_fingerprint is not None
)
def _match_hostname(cert, asserted_hostname):
try:
match_hostname(cert, asserted_hostname)
except CertificateError as e:
log.warning(
"Certificate did not match expected hostname: %s. Certificate: %s",
asserted_hostname,
cert,
)
# Add cert to exception and reraise so client code can inspect
# the cert when catching the exception, if they want to
e._peer_cert = cert
raise
if ssl:
# Make a copy for testing.
UnverifiedHTTPSConnection = HTTPSConnection
HTTPSConnection = VerifiedHTTPSConnection
else:
HTTPSConnection = DummyConnection