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from __future__ import absolute_import
import datetime
import logging
import os
import sys
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 updating RECENT_DATE, move it to
# within two years of the current date, and no
# earlier than 6 months ago.
RECENT_DATE = datetime.date(2016, 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.
.. note:: This is ignored for Python 2.6. It is only applied for 2.7 and 3.x
- ``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 six.PY3: # Python 3
kw.pop('strict', None)
# Pre-set source_address in case we have an older Python like 2.6.
self.source_address = kw.get('source_address')
if sys.version_info < (2, 7): # Python 2.6
# _HTTPConnection on Python 2.6 will balk at this keyword arg, but
# not newer versions. We can still use it when creating a
# connection though, so we pop it *after* we have saved it as
# self.source_address.
kw.pop('source_address', None)
#: 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)
# Superclass also sets self.source_address in Python 2.7+.
_HTTPConnection.__init__(self, *args, **kw)
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.host, self.port), self.timeout, **extra_kw)
except SocketTimeout as e:
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
# the _tunnel_host attribute was added in python 2.6.3 (via
# http://hg.python.org/cpython/rev/0f57b30a152f) so pythons 2.6(0-2) do
# not have them.
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 + (six.binary_type,)
if isinstance(body, stringish_types):
body = (body,)
for chunk in body:
if not chunk:
continue
if not isinstance(chunk, six.binary_type):
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,
strict=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT,
ssl_context=None, **kw):
HTTPConnection.__init__(self, host, port, strict=strict,
timeout=timeout, **kw)
self.key_file = key_file
self.cert_file = cert_file
self.ssl_context = ssl_context
# Required property for Google AppEngine 1.9.0 which otherwise causes
# HTTPS requests to go out as HTTP. (See Issue #356)
self._protocol = 'https'
def connect(self):
conn = self._new_conn()
self._prepare_conn(conn)
if self.ssl_context is None:
self.ssl_context = create_urllib3_context(
ssl_version=resolve_ssl_version(None),
cert_reqs=resolve_cert_reqs(None),
)
self.sock = ssl_wrap_socket(
sock=conn,
keyfile=self.key_file,
certfile=self.cert_file,
ssl_context=self.ssl_context,
)
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, 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 can try to guess. If the user gave
# us a cert database, we assume they want to use it: otherwise, if
# they gave us an SSL Context object we should use whatever is set for
# it.
if cert_reqs is None:
if ca_certs or ca_cert_dir:
cert_reqs = 'CERT_REQUIRED'
elif self.ssl_context is not None:
cert_reqs = self.ssl_context.verify_mode
self.key_file = key_file
self.cert_file = cert_file
self.cert_reqs = cert_reqs
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
if getattr(self, '_tunnel_host', None):
# _tunnel_host was added in Python 2.6.3
# (See: http://hg.python.org/cpython/rev/0f57b30a152f)
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
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
if self.ssl_context is None:
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)
self.sock = ssl_wrap_socket(
sock=conn,
keyfile=self.key_file,
certfile=self.cert_file,
ca_certs=self.ca_certs,
ca_cert_dir=self.ca_cert_dir,
server_hostname=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/shazow/urllib3/issues/497 '
'for details.)'.format(hostname)),
SubjectAltNameWarning
)
_match_hostname(cert, self.assert_hostname or 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.error(
'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
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