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Diffstat (limited to 'urllib3/connection.py')
| -rw-r--r-- | urllib3/connection.py | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/urllib3/connection.py b/urllib3/connection.py new file mode 100644 index 0000000..f64dd1a --- /dev/null +++ b/urllib3/connection.py @@ -0,0 +1,268 @@ +import datetime +import sys +import socket +from socket import timeout as SocketTimeout +import warnings +from .packages import six + +try: # Python 3 + from http.client import HTTPConnection as _HTTPConnection, HTTPException +except ImportError: + from httplib import HTTPConnection as _HTTPConnection, HTTPException + + +class DummyConnection(object): + "Used to detect a failed ConnectionCls import." + pass + + +try: # Compiled with SSL? + HTTPSConnection = DummyConnection + 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 ( + ConnectTimeoutError, + SystemTimeWarning, + SubjectAltNameWarning, +) +from .packages.ssl_match_hostname import match_hostname + +from .util.ssl_ import ( + resolve_cert_reqs, + resolve_ssl_version, + ssl_wrap_socket, + assert_fingerprint, +) + + +from .util import connection + +port_by_scheme = { + 'http': 80, + 'https': 443, +} + +RECENT_DATE = datetime.date(2014, 1, 1) + + +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: + raise ConnectTimeoutError( + self, "Connection to %s timed out. (connect timeout=%s)" % + (self.host, self.timeout)) + + 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) + + +class HTTPSConnection(HTTPConnection): + default_port = port_by_scheme['https'] + + def __init__(self, host, port=None, key_file=None, cert_file=None, + strict=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT, **kw): + + HTTPConnection.__init__(self, host, port, strict=strict, + timeout=timeout, **kw) + + self.key_file = key_file + self.cert_file = cert_file + + # 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) + self.sock = ssl.wrap_socket(conn, self.key_file, self.cert_file) + + +class VerifiedHTTPSConnection(HTTPSConnection): + """ + Based on httplib.HTTPSConnection but wraps the socket with + SSL certification. + """ + cert_reqs = None + ca_certs = 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): + + if ca_certs and cert_reqs is None: + cert_reqs = 'CERT_REQUIRED' + + self.key_file = key_file + self.cert_file = cert_file + self.cert_reqs = cert_reqs + self.ca_certs = ca_certs + self.assert_hostname = assert_hostname + self.assert_fingerprint = assert_fingerprint + + def connect(self): + # Add certificate verification + conn = self._new_conn() + + resolved_cert_reqs = resolve_cert_reqs(self.cert_reqs) + resolved_ssl_version = resolve_ssl_version(self.ssl_version) + + 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 + self.sock = ssl_wrap_socket(conn, self.key_file, self.cert_file, + cert_reqs=resolved_cert_reqs, + ca_certs=self.ca_certs, + server_hostname=hostname, + ssl_version=resolved_ssl_version) + + if self.assert_fingerprint: + assert_fingerprint(self.sock.getpeercert(binary_form=True), + self.assert_fingerprint) + elif resolved_cert_reqs != ssl.CERT_NONE \ + and self.assert_hostname is not False: + 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 = (resolved_cert_reqs == ssl.CERT_REQUIRED + or self.assert_fingerprint is not None) + + +if ssl: + # Make a copy for testing. + UnverifiedHTTPSConnection = HTTPSConnection + HTTPSConnection = VerifiedHTTPSConnection +else: + HTTPSConnection = DummyConnection |