Files
pyfa/pycrest/weak_ciphers.py
2015-10-17 21:41:24 -04:00

141 lines
5.2 KiB
Python

import datetime
import ssl
import sys
import warnings
from requests.adapters import HTTPAdapter
try:
from requests.packages import urllib3
from requests.packages.urllib3.util import ssl_
from requests.packages.urllib3.exceptions import (
SystemTimeWarning,
SecurityWarning,
)
from requests.packages.urllib3.packages.ssl_match_hostname import \
match_hostname
except:
import urllib3
from urllib3.util import ssl_
from urllib3.exceptions import (
SystemTimeWarning,
SecurityWarning,
)
from urllib3.packages.ssl_match_hostname import \
match_hostname
class WeakCiphersHTTPSConnection(
urllib3.connection.VerifiedHTTPSConnection): # pragma: no cover
# Python versions >=2.7.9 and >=3.4.1 do not (by default) allow ciphers
# with MD5. Unfortunately, the CREST public server _only_ supports
# TLS_RSA_WITH_RC4_128_MD5 (as of 5 Jan 2015). The cipher list below is
# nearly identical except for allowing that cipher as a last resort (and
# excluding export versions of ciphers).
DEFAULT_CIPHERS = (
'ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:'
'ECDH+HIGH:DH+HIGH:ECDH+3DES:DH+3DES:RSA+AESGCM:RSA+AES:RSA+HIGH:'
'RSA+3DES:ECDH+RC4:DH+RC4:RSA+RC4:!aNULL:!eNULL:!EXP:-MD5:RSA+RC4+MD5'
)
def __init__(self, host, port, ciphers=None, **kwargs):
self.ciphers = ciphers if ciphers is not None else self.DEFAULT_CIPHERS
super(WeakCiphersHTTPSConnection, self).__init__(host, port, **kwargs)
def connect(self):
# Yup, copied in VerifiedHTTPSConnection.connect just to change the
# default cipher list.
# Add certificate verification
conn = self._new_conn()
resolved_cert_reqs = ssl_.resolve_cert_reqs(self.cert_reqs)
resolved_ssl_version = ssl_.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() < urllib3.connection.RECENT_DATE
if is_time_off:
warnings.warn((
'System time is way off (before {0}). This will probably '
'lead to SSL verification errors').format(
urllib3.connection.RECENT_DATE),
SystemTimeWarning
)
# Wrap socket using verification with the root certs in
# trusted_root_certs
self.sock = ssl_.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,
ciphers=self.ciphers)
if self.assert_fingerprint:
ssl_.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 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.)'),
SecurityWarning
)
match_hostname(cert, self.assert_hostname or hostname)
self.is_verified = (resolved_cert_reqs == ssl.CERT_REQUIRED
or self.assert_fingerprint is not None)
class WeakCiphersHTTPSConnectionPool(
urllib3.connectionpool.HTTPSConnectionPool):
ConnectionCls = WeakCiphersHTTPSConnection
class WeakCiphersPoolManager(urllib3.poolmanager.PoolManager):
def _new_pool(self, scheme, host, port):
if scheme == 'https':
return WeakCiphersHTTPSConnectionPool(host, port,
**(self.connection_pool_kw))
return super(WeakCiphersPoolManager, self)._new_pool(scheme, host,
port)
class WeakCiphersAdapter(HTTPAdapter):
""""Transport adapter" that allows us to use TLS_RSA_WITH_RC4_128_MD5."""
def init_poolmanager(self, connections, maxsize, block=False,
**pool_kwargs):
# Rewrite of the requests.adapters.HTTPAdapter.init_poolmanager method
# to use WeakCiphersPoolManager instead of urllib3's PoolManager
self._pool_connections = connections
self._pool_maxsize = maxsize
self._pool_block = block
self.poolmanager = WeakCiphersPoolManager(num_pools=connections,
maxsize=maxsize, block=block, strict=True, **pool_kwargs)