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Your IP : 216.73.216.116
"""
"""
# Created on 2013.08.05
#
# Author: Giovanni Cannata
#
# Copyright 2013 - 2020 Giovanni Cannata
#
# This file is part of ldap3.
#
# ldap3 is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published
# by the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# ldap3 is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with ldap3 in the COPYING and COPYING.LESSER files.
# If not, see <http://www.gnu.org/licenses/>.
from .exceptions import LDAPSSLNotSupportedError, LDAPSSLConfigurationError, LDAPCertificateError, start_tls_exception_factory, LDAPStartTLSError
from .. import SEQUENCE_TYPES
from ..utils.log import log, log_enabled, ERROR, BASIC, NETWORK
try:
# noinspection PyUnresolvedReferences
import ssl
except ImportError:
if log_enabled(ERROR):
log(ERROR, 'SSL not supported in this Python interpreter')
raise LDAPSSLNotSupportedError('SSL not supported in this Python interpreter')
try:
from ssl import match_hostname, CertificateError # backport for python2 missing ssl functionalities
except ImportError:
from ..utils.tls_backport import CertificateError
from ..utils.tls_backport import match_hostname
if log_enabled(BASIC):
log(BASIC, 'using tls_backport')
try: # try to use SSLContext
# noinspection PyUnresolvedReferences
from ssl import create_default_context, Purpose # defined in Python 3.4 and Python 2.7.9
use_ssl_context = True
except ImportError:
use_ssl_context = False
if log_enabled(BASIC):
log(BASIC, 'SSLContext unavailable')
from os import path
# noinspection PyProtectedMember
class Tls(object):
"""
tls/ssl configuration for Server object
Starting from python 2.7.9 and python 3.4 uses the SSLContext object
that tries to read the CAs defined at system level
ca_certs_path and ca_certs_data are valid only when using SSLContext
local_private_key_password is valid only when using SSLContext
ssl_options is valid only when using SSLContext
sni is the server name for Server Name Indication (when available)
"""
def __init__(self,
local_private_key_file=None,
local_certificate_file=None,
validate=ssl.CERT_NONE,
version=None,
ssl_options=None,
ca_certs_file=None,
valid_names=None,
ca_certs_path=None,
ca_certs_data=None,
local_private_key_password=None,
ciphers=None,
sni=None):
if ssl_options is None:
ssl_options = []
self.ssl_options = ssl_options
if validate in [ssl.CERT_NONE, ssl.CERT_OPTIONAL, ssl.CERT_REQUIRED]:
self.validate = validate
elif validate:
if log_enabled(ERROR):
log(ERROR, 'invalid validate parameter <%s>', validate)
raise LDAPSSLConfigurationError('invalid validate parameter')
if ca_certs_file and path.exists(ca_certs_file):
self.ca_certs_file = ca_certs_file
elif ca_certs_file:
if log_enabled(ERROR):
log(ERROR, 'invalid CA public key file <%s>', ca_certs_file)
raise LDAPSSLConfigurationError('invalid CA public key file')
else:
self.ca_certs_file = None
if ca_certs_path and use_ssl_context and path.exists(ca_certs_path):
self.ca_certs_path = ca_certs_path
elif ca_certs_path and not use_ssl_context:
if log_enabled(ERROR):
log(ERROR, 'cannot use CA public keys path, SSLContext not available')
raise LDAPSSLNotSupportedError('cannot use CA public keys path, SSLContext not available')
elif ca_certs_path:
if log_enabled(ERROR):
log(ERROR, 'invalid CA public keys path <%s>', ca_certs_path)
raise LDAPSSLConfigurationError('invalid CA public keys path')
else:
self.ca_certs_path = None
if ca_certs_data and use_ssl_context:
self.ca_certs_data = ca_certs_data
elif ca_certs_data:
if log_enabled(ERROR):
log(ERROR, 'cannot use CA data, SSLContext not available')
raise LDAPSSLNotSupportedError('cannot use CA data, SSLContext not available')
else:
self.ca_certs_data = None
if local_private_key_password and use_ssl_context:
self.private_key_password = local_private_key_password
elif local_private_key_password:
if log_enabled(ERROR):
log(ERROR, 'cannot use local private key password, SSLContext not available')
raise LDAPSSLNotSupportedError('cannot use local private key password, SSLContext is not available')
else:
self.private_key_password = None
self.version = version
self.private_key_file = local_private_key_file
self.certificate_file = local_certificate_file
self.valid_names = valid_names
self.ciphers = ciphers
self.sni = sni
if log_enabled(BASIC):
log(BASIC, 'instantiated Tls: <%r>' % self)
def __str__(self):
s = [
'protocol: ' + str(self.version),
'client private key: ' + ('present ' if self.private_key_file else 'not present'),
'client certificate: ' + ('present ' if self.certificate_file else 'not present'),
'private key password: ' + ('present ' if self.private_key_password else 'not present'),
'CA certificates file: ' + ('present ' if self.ca_certs_file else 'not present'),
'CA certificates path: ' + ('present ' if self.ca_certs_path else 'not present'),
'CA certificates data: ' + ('present ' if self.ca_certs_data else 'not present'),
'verify mode: ' + str(self.validate),
'valid names: ' + str(self.valid_names),
'ciphers: ' + str(self.ciphers),
'sni: ' + str(self.sni)
]
return ' - '.join(s)
def __repr__(self):
r = '' if self.private_key_file is None else ', local_private_key_file={0.private_key_file!r}'.format(self)
r += '' if self.certificate_file is None else ', local_certificate_file={0.certificate_file!r}'.format(self)
r += '' if self.validate is None else ', validate={0.validate!r}'.format(self)
r += '' if self.version is None else ', version={0.version!r}'.format(self)
r += '' if self.ca_certs_file is None else ', ca_certs_file={0.ca_certs_file!r}'.format(self)
r += '' if self.ca_certs_path is None else ', ca_certs_path={0.ca_certs_path!r}'.format(self)
r += '' if self.ca_certs_data is None else ', ca_certs_data={0.ca_certs_data!r}'.format(self)
r += '' if self.ciphers is None else ', ciphers={0.ciphers!r}'.format(self)
r += '' if self.sni is None else ', sni={0.sni!r}'.format(self)
r = 'Tls(' + r[2:] + ')'
return r
def wrap_socket(self, connection, do_handshake=False):
"""
Adds TLS to the connection socket
"""
if use_ssl_context:
if self.version is None: # uses the default ssl context for reasonable security
ssl_context = create_default_context(purpose=Purpose.SERVER_AUTH,
cafile=self.ca_certs_file,
capath=self.ca_certs_path,
cadata=self.ca_certs_data)
else: # code from create_default_context in the Python standard library 3.5.1, creates a ssl context with the specificd protocol version
ssl_context = ssl.SSLContext(self.version)
if self.ca_certs_file or self.ca_certs_path or self.ca_certs_data:
ssl_context.load_verify_locations(self.ca_certs_file, self.ca_certs_path, self.ca_certs_data)
elif self.validate != ssl.CERT_NONE:
ssl_context.load_default_certs(Purpose.SERVER_AUTH)
if self.certificate_file:
ssl_context.load_cert_chain(self.certificate_file, keyfile=self.private_key_file, password=self.private_key_password)
ssl_context.check_hostname = False
ssl_context.verify_mode = self.validate
for option in self.ssl_options:
ssl_context.options |= option
if self.ciphers:
try:
ssl_context.set_ciphers(self.ciphers)
except ssl.SSLError:
pass
if self.sni:
wrapped_socket = ssl_context.wrap_socket(connection.socket, server_side=False, do_handshake_on_connect=do_handshake, server_hostname=self.sni)
else:
wrapped_socket = ssl_context.wrap_socket(connection.socket, server_side=False, do_handshake_on_connect=do_handshake)
if log_enabled(NETWORK):
log(NETWORK, 'socket wrapped with SSL using SSLContext for <%s>', connection)
else:
if self.version is None and hasattr(ssl, 'PROTOCOL_SSLv23'):
self.version = ssl.PROTOCOL_SSLv23
if self.ciphers:
try:
wrapped_socket = ssl.wrap_socket(connection.socket,
keyfile=self.private_key_file,
certfile=self.certificate_file,
server_side=False,
cert_reqs=self.validate,
ssl_version=self.version,
ca_certs=self.ca_certs_file,
do_handshake_on_connect=do_handshake,
ciphers=self.ciphers)
except ssl.SSLError:
raise
except TypeError: # in python2.6 no ciphers argument is present, failback to self.ciphers=None
self.ciphers = None
if not self.ciphers:
wrapped_socket = ssl.wrap_socket(connection.socket,
keyfile=self.private_key_file,
certfile=self.certificate_file,
server_side=False,
cert_reqs=self.validate,
ssl_version=self.version,
ca_certs=self.ca_certs_file,
do_handshake_on_connect=do_handshake)
if log_enabled(NETWORK):
log(NETWORK, 'socket wrapped with SSL for <%s>', connection)
if do_handshake and (self.validate == ssl.CERT_REQUIRED or self.validate == ssl.CERT_OPTIONAL):
check_hostname(wrapped_socket, connection.server.host, self.valid_names)
connection.socket = wrapped_socket
return
def start_tls(self, connection):
if connection.server.ssl: # ssl already established at server level
return False
if (connection.tls_started and not connection._executing_deferred) or connection.strategy._outstanding or connection.sasl_in_progress:
# Per RFC 4513 (3.1.1)
if log_enabled(ERROR):
log(ERROR, "can't start tls because operations are in progress for <%s>", self)
return False
connection.starting_tls = True
if log_enabled(BASIC):
log(BASIC, 'starting tls for <%s>', connection)
if not connection.strategy.sync:
connection._awaiting_for_async_start_tls = True # some flaky servers (OpenLDAP) doesn't return the extended response name in response
result = connection.extended('1.3.6.1.4.1.1466.20037')
if not connection.strategy.sync:
# asynchronous - _start_tls must be executed by the strategy
response = connection.get_response(result)
if response != (None, None):
if log_enabled(BASIC):
log(BASIC, 'tls started for <%s>', connection)
return True
else:
if log_enabled(BASIC):
log(BASIC, 'tls not started for <%s>', connection)
return False
else:
if connection.result['description'] not in ['success']:
# startTLS failed
connection.last_error = 'startTLS failed - ' + str(connection.result['description'])
if log_enabled(ERROR):
log(ERROR, '%s for <%s>', connection.last_error, connection)
raise LDAPStartTLSError(connection.last_error)
if log_enabled(BASIC):
log(BASIC, 'tls started for <%s>', connection)
return self._start_tls(connection)
def _start_tls(self, connection):
try:
self.wrap_socket(connection, do_handshake=True)
except Exception as e:
connection.last_error = 'wrap socket error: ' + str(e)
if log_enabled(ERROR):
log(ERROR, 'error <%s> wrapping socket for TLS in <%s>', connection.last_error, connection)
raise start_tls_exception_factory(e)(connection.last_error)
finally:
connection.starting_tls = False
if connection.usage:
connection._usage.wrapped_sockets += 1
connection.tls_started = True
return True
def check_hostname(sock, server_name, additional_names):
server_certificate = sock.getpeercert()
if log_enabled(NETWORK):
log(NETWORK, 'certificate found for %s: %s', sock, server_certificate)
if additional_names:
host_names = [server_name] + (additional_names if isinstance(additional_names, SEQUENCE_TYPES) else [additional_names])
else:
host_names = [server_name]
for host_name in host_names:
if not host_name:
continue
elif host_name == '*':
if log_enabled(NETWORK):
log(NETWORK, 'certificate matches * wildcard')
return # valid
try:
match_hostname(server_certificate, host_name) # raise CertificateError if certificate doesn't match server name
if log_enabled(NETWORK):
log(NETWORK, 'certificate matches host name <%s>', host_name)
return # valid
except CertificateError as e:
if log_enabled(NETWORK):
log(NETWORK, str(e))
if log_enabled(ERROR):
log(ERROR, "hostname doesn't match certificate")
raise LDAPCertificateError("certificate %s doesn't match any name in %s " % (server_certificate, str(host_names)))