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1053 lines
37 KiB
1053 lines
37 KiB
# Wrapper module for _ssl, providing some additional facilities
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# implemented in Python. Written by Bill Janssen.
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"""This module provides some more Pythonic support for SSL.
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Object types:
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SSLSocket -- subtype of socket.socket which does SSL over the socket
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Exceptions:
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SSLError -- exception raised for I/O errors
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Functions:
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cert_time_to_seconds -- convert time string used for certificate
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notBefore and notAfter functions to integer
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seconds past the Epoch (the time values
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returned from time.time())
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fetch_server_certificate (HOST, PORT) -- fetch the certificate provided
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by the server running on HOST at port PORT. No
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validation of the certificate is performed.
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Integer constants:
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SSL_ERROR_ZERO_RETURN
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SSL_ERROR_WANT_READ
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SSL_ERROR_WANT_WRITE
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SSL_ERROR_WANT_X509_LOOKUP
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SSL_ERROR_SYSCALL
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SSL_ERROR_SSL
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SSL_ERROR_WANT_CONNECT
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SSL_ERROR_EOF
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SSL_ERROR_INVALID_ERROR_CODE
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The following group define certificate requirements that one side is
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allowing/requiring from the other side:
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CERT_NONE - no certificates from the other side are required (or will
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be looked at if provided)
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CERT_OPTIONAL - certificates are not required, but if provided will be
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validated, and if validation fails, the connection will
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also fail
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CERT_REQUIRED - certificates are required, and will be validated, and
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if validation fails, the connection will also fail
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The following constants identify various SSL protocol variants:
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PROTOCOL_SSLv2
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PROTOCOL_SSLv3
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PROTOCOL_SSLv23
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PROTOCOL_TLS
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PROTOCOL_TLSv1
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PROTOCOL_TLSv1_1
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PROTOCOL_TLSv1_2
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The following constants identify various SSL alert message descriptions as per
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http://www.iana.org/assignments/tls-parameters/tls-parameters.xml#tls-parameters-6
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ALERT_DESCRIPTION_CLOSE_NOTIFY
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ALERT_DESCRIPTION_UNEXPECTED_MESSAGE
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ALERT_DESCRIPTION_BAD_RECORD_MAC
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ALERT_DESCRIPTION_RECORD_OVERFLOW
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ALERT_DESCRIPTION_DECOMPRESSION_FAILURE
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ALERT_DESCRIPTION_HANDSHAKE_FAILURE
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ALERT_DESCRIPTION_BAD_CERTIFICATE
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ALERT_DESCRIPTION_UNSUPPORTED_CERTIFICATE
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ALERT_DESCRIPTION_CERTIFICATE_REVOKED
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ALERT_DESCRIPTION_CERTIFICATE_EXPIRED
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ALERT_DESCRIPTION_CERTIFICATE_UNKNOWN
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ALERT_DESCRIPTION_ILLEGAL_PARAMETER
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ALERT_DESCRIPTION_UNKNOWN_CA
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ALERT_DESCRIPTION_ACCESS_DENIED
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ALERT_DESCRIPTION_DECODE_ERROR
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ALERT_DESCRIPTION_DECRYPT_ERROR
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ALERT_DESCRIPTION_PROTOCOL_VERSION
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ALERT_DESCRIPTION_INSUFFICIENT_SECURITY
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ALERT_DESCRIPTION_INTERNAL_ERROR
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ALERT_DESCRIPTION_USER_CANCELLED
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ALERT_DESCRIPTION_NO_RENEGOTIATION
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ALERT_DESCRIPTION_UNSUPPORTED_EXTENSION
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ALERT_DESCRIPTION_CERTIFICATE_UNOBTAINABLE
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ALERT_DESCRIPTION_UNRECOGNIZED_NAME
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ALERT_DESCRIPTION_BAD_CERTIFICATE_STATUS_RESPONSE
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ALERT_DESCRIPTION_BAD_CERTIFICATE_HASH_VALUE
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ALERT_DESCRIPTION_UNKNOWN_PSK_IDENTITY
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"""
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import textwrap
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import re
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import sys
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import os
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from collections import namedtuple
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from contextlib import closing
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import _ssl # if we can't import it, let the error propagate
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from _ssl import OPENSSL_VERSION_NUMBER, OPENSSL_VERSION_INFO, OPENSSL_VERSION
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from _ssl import _SSLContext
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from _ssl import (
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SSLError, SSLZeroReturnError, SSLWantReadError, SSLWantWriteError,
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SSLSyscallError, SSLEOFError,
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)
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from _ssl import CERT_NONE, CERT_OPTIONAL, CERT_REQUIRED
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from _ssl import txt2obj as _txt2obj, nid2obj as _nid2obj
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from _ssl import RAND_status, RAND_add
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try:
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from _ssl import RAND_egd
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except ImportError:
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# LibreSSL does not provide RAND_egd
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pass
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def _import_symbols(prefix):
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for n in dir(_ssl):
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if n.startswith(prefix):
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globals()[n] = getattr(_ssl, n)
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_import_symbols('OP_')
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_import_symbols('ALERT_DESCRIPTION_')
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_import_symbols('SSL_ERROR_')
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_import_symbols('PROTOCOL_')
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_import_symbols('VERIFY_')
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from _ssl import HAS_SNI, HAS_ECDH, HAS_NPN, HAS_ALPN, HAS_TLSv1_3
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from _ssl import _OPENSSL_API_VERSION
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_PROTOCOL_NAMES = {value: name for name, value in globals().items()
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if name.startswith('PROTOCOL_')
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and name != 'PROTOCOL_SSLv23'}
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PROTOCOL_SSLv23 = PROTOCOL_TLS
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try:
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_SSLv2_IF_EXISTS = PROTOCOL_SSLv2
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except NameError:
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_SSLv2_IF_EXISTS = None
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from socket import socket, _fileobject, _delegate_methods, error as socket_error
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if sys.platform == "win32" or os.name == "nt":
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from _ssl import enum_certificates, enum_crls
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from socket import socket, AF_INET, SOCK_STREAM, create_connection
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from socket import SOL_SOCKET, SO_TYPE
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import base64 # for DER-to-PEM translation
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import errno
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import warnings
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if _ssl.HAS_TLS_UNIQUE:
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CHANNEL_BINDING_TYPES = ['tls-unique']
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else:
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CHANNEL_BINDING_TYPES = []
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# Disable weak or insecure ciphers by default
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# (OpenSSL's default setting is 'DEFAULT:!aNULL:!eNULL')
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# Enable a better set of ciphers by default
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# This list has been explicitly chosen to:
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# * TLS 1.3 ChaCha20 and AES-GCM cipher suites
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# * Prefer cipher suites that offer perfect forward secrecy (DHE/ECDHE)
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# * Prefer ECDHE over DHE for better performance
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# * Prefer AEAD over CBC for better performance and security
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# * Prefer AES-GCM over ChaCha20 because most platforms have AES-NI
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# (ChaCha20 needs OpenSSL 1.1.0 or patched 1.0.2)
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# * Prefer any AES-GCM and ChaCha20 over any AES-CBC for better
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# performance and security
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# * Then Use HIGH cipher suites as a fallback
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# * Disable NULL authentication, NULL encryption, 3DES and MD5 MACs
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# for security reasons
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_DEFAULT_CIPHERS = (
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'TLS13-AES-256-GCM-SHA384:TLS13-CHACHA20-POLY1305-SHA256:'
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'TLS13-AES-128-GCM-SHA256:'
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'ECDH+AESGCM:ECDH+CHACHA20:DH+AESGCM:DH+CHACHA20:ECDH+AES256:DH+AES256:'
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'ECDH+AES128:DH+AES:ECDH+HIGH:DH+HIGH:RSA+AESGCM:RSA+AES:RSA+HIGH:'
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'!aNULL:!eNULL:!MD5:!3DES'
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)
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# Restricted and more secure ciphers for the server side
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# This list has been explicitly chosen to:
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# * TLS 1.3 ChaCha20 and AES-GCM cipher suites
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# * Prefer cipher suites that offer perfect forward secrecy (DHE/ECDHE)
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# * Prefer ECDHE over DHE for better performance
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# * Prefer AEAD over CBC for better performance and security
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# * Prefer AES-GCM over ChaCha20 because most platforms have AES-NI
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# * Prefer any AES-GCM and ChaCha20 over any AES-CBC for better
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# performance and security
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# * Then Use HIGH cipher suites as a fallback
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# * Disable NULL authentication, NULL encryption, MD5 MACs, DSS, RC4, and
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# 3DES for security reasons
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_RESTRICTED_SERVER_CIPHERS = (
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'TLS13-AES-256-GCM-SHA384:TLS13-CHACHA20-POLY1305-SHA256:'
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'TLS13-AES-128-GCM-SHA256:'
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'ECDH+AESGCM:ECDH+CHACHA20:DH+AESGCM:DH+CHACHA20:ECDH+AES256:DH+AES256:'
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'ECDH+AES128:DH+AES:ECDH+HIGH:DH+HIGH:RSA+AESGCM:RSA+AES:RSA+HIGH:'
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'!aNULL:!eNULL:!MD5:!DSS:!RC4:!3DES'
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)
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class CertificateError(ValueError):
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pass
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def _dnsname_match(dn, hostname, max_wildcards=1):
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"""Matching according to RFC 6125, section 6.4.3
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http://tools.ietf.org/html/rfc6125#section-6.4.3
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"""
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pats = []
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if not dn:
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return False
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pieces = dn.split(r'.')
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leftmost = pieces[0]
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remainder = pieces[1:]
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wildcards = leftmost.count('*')
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if wildcards > max_wildcards:
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# Issue #17980: avoid denials of service by refusing more
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# than one wildcard per fragment. A survery of established
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# policy among SSL implementations showed it to be a
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# reasonable choice.
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raise CertificateError(
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"too many wildcards in certificate DNS name: " + repr(dn))
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# speed up common case w/o wildcards
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if not wildcards:
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return dn.lower() == hostname.lower()
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# RFC 6125, section 6.4.3, subitem 1.
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# The client SHOULD NOT attempt to match a presented identifier in which
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# the wildcard character comprises a label other than the left-most label.
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if leftmost == '*':
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# When '*' is a fragment by itself, it matches a non-empty dotless
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# fragment.
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pats.append('[^.]+')
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elif leftmost.startswith('xn--') or hostname.startswith('xn--'):
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# RFC 6125, section 6.4.3, subitem 3.
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# The client SHOULD NOT attempt to match a presented identifier
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# where the wildcard character is embedded within an A-label or
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# U-label of an internationalized domain name.
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pats.append(re.escape(leftmost))
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else:
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# Otherwise, '*' matches any dotless string, e.g. www*
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pats.append(re.escape(leftmost).replace(r'\*', '[^.]*'))
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# add the remaining fragments, ignore any wildcards
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for frag in remainder:
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pats.append(re.escape(frag))
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pat = re.compile(r'\A' + r'\.'.join(pats) + r'\Z', re.IGNORECASE)
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return pat.match(hostname)
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def match_hostname(cert, hostname):
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"""Verify that *cert* (in decoded format as returned by
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SSLSocket.getpeercert()) matches the *hostname*. RFC 2818 and RFC 6125
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rules are followed, but IP addresses are not accepted for *hostname*.
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CertificateError is raised on failure. On success, the function
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returns nothing.
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"""
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if not cert:
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raise ValueError("empty or no certificate, match_hostname needs a "
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"SSL socket or SSL context with either "
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"CERT_OPTIONAL or CERT_REQUIRED")
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dnsnames = []
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san = cert.get('subjectAltName', ())
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for key, value in san:
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if key == 'DNS':
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if _dnsname_match(value, hostname):
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return
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dnsnames.append(value)
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if not dnsnames:
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# The subject is only checked when there is no dNSName entry
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# in subjectAltName
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for sub in cert.get('subject', ()):
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for key, value in sub:
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# XXX according to RFC 2818, the most specific Common Name
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# must be used.
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if key == 'commonName':
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if _dnsname_match(value, hostname):
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return
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dnsnames.append(value)
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if len(dnsnames) > 1:
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raise CertificateError("hostname %r "
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"doesn't match either of %s"
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% (hostname, ', '.join(map(repr, dnsnames))))
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elif len(dnsnames) == 1:
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raise CertificateError("hostname %r "
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"doesn't match %r"
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% (hostname, dnsnames[0]))
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else:
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raise CertificateError("no appropriate commonName or "
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"subjectAltName fields were found")
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|
|
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DefaultVerifyPaths = namedtuple("DefaultVerifyPaths",
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"cafile capath openssl_cafile_env openssl_cafile openssl_capath_env "
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"openssl_capath")
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def get_default_verify_paths():
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"""Return paths to default cafile and capath.
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"""
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parts = _ssl.get_default_verify_paths()
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# environment vars shadow paths
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cafile = os.environ.get(parts[0], parts[1])
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capath = os.environ.get(parts[2], parts[3])
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return DefaultVerifyPaths(cafile if os.path.isfile(cafile) else None,
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capath if os.path.isdir(capath) else None,
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*parts)
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class _ASN1Object(namedtuple("_ASN1Object", "nid shortname longname oid")):
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"""ASN.1 object identifier lookup
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"""
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__slots__ = ()
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def __new__(cls, oid):
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return super(_ASN1Object, cls).__new__(cls, *_txt2obj(oid, name=False))
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@classmethod
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def fromnid(cls, nid):
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"""Create _ASN1Object from OpenSSL numeric ID
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"""
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return super(_ASN1Object, cls).__new__(cls, *_nid2obj(nid))
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@classmethod
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def fromname(cls, name):
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"""Create _ASN1Object from short name, long name or OID
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"""
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return super(_ASN1Object, cls).__new__(cls, *_txt2obj(name, name=True))
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|
|
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class Purpose(_ASN1Object):
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"""SSLContext purpose flags with X509v3 Extended Key Usage objects
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"""
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Purpose.SERVER_AUTH = Purpose('1.3.6.1.5.5.7.3.1')
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Purpose.CLIENT_AUTH = Purpose('1.3.6.1.5.5.7.3.2')
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|
|
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class SSLContext(_SSLContext):
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"""An SSLContext holds various SSL-related configuration options and
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data, such as certificates and possibly a private key."""
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__slots__ = ('protocol', '__weakref__')
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_windows_cert_stores = ("CA", "ROOT")
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def __new__(cls, protocol, *args, **kwargs):
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self = _SSLContext.__new__(cls, protocol)
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if protocol != _SSLv2_IF_EXISTS:
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self.set_ciphers(_DEFAULT_CIPHERS)
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return self
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def __init__(self, protocol):
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self.protocol = protocol
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def wrap_socket(self, sock, server_side=False,
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do_handshake_on_connect=True,
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suppress_ragged_eofs=True,
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server_hostname=None):
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return SSLSocket(sock=sock, server_side=server_side,
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do_handshake_on_connect=do_handshake_on_connect,
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suppress_ragged_eofs=suppress_ragged_eofs,
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server_hostname=server_hostname,
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_context=self)
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def set_npn_protocols(self, npn_protocols):
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protos = bytearray()
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for protocol in npn_protocols:
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b = protocol.encode('ascii')
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|
if len(b) == 0 or len(b) > 255:
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raise SSLError('NPN protocols must be 1 to 255 in length')
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protos.append(len(b))
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protos.extend(b)
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self._set_npn_protocols(protos)
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def set_alpn_protocols(self, alpn_protocols):
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protos = bytearray()
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for protocol in alpn_protocols:
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b = protocol.encode('ascii')
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|
if len(b) == 0 or len(b) > 255:
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raise SSLError('ALPN protocols must be 1 to 255 in length')
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protos.append(len(b))
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|
protos.extend(b)
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|
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self._set_alpn_protocols(protos)
|
|
|
|
def _load_windows_store_certs(self, storename, purpose):
|
|
certs = bytearray()
|
|
try:
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|
for cert, encoding, trust in enum_certificates(storename):
|
|
# CA certs are never PKCS#7 encoded
|
|
if encoding == "x509_asn":
|
|
if trust is True or purpose.oid in trust:
|
|
certs.extend(cert)
|
|
except OSError:
|
|
warnings.warn("unable to enumerate Windows certificate store")
|
|
if certs:
|
|
self.load_verify_locations(cadata=certs)
|
|
return certs
|
|
|
|
def load_default_certs(self, purpose=Purpose.SERVER_AUTH):
|
|
if not isinstance(purpose, _ASN1Object):
|
|
raise TypeError(purpose)
|
|
if sys.platform == "win32" or os.name == "nt":
|
|
for storename in self._windows_cert_stores:
|
|
self._load_windows_store_certs(storename, purpose)
|
|
self.set_default_verify_paths()
|
|
|
|
|
|
def create_default_context(purpose=Purpose.SERVER_AUTH, cafile=None,
|
|
capath=None, cadata=None):
|
|
"""Create a SSLContext object with default settings.
|
|
|
|
NOTE: The protocol and settings may change anytime without prior
|
|
deprecation. The values represent a fair balance between maximum
|
|
compatibility and security.
|
|
"""
|
|
if not isinstance(purpose, _ASN1Object):
|
|
raise TypeError(purpose)
|
|
|
|
context = SSLContext(PROTOCOL_TLS)
|
|
|
|
# SSLv2 considered harmful.
|
|
context.options |= OP_NO_SSLv2
|
|
|
|
# SSLv3 has problematic security and is only required for really old
|
|
# clients such as IE6 on Windows XP
|
|
context.options |= OP_NO_SSLv3
|
|
|
|
# disable compression to prevent CRIME attacks (OpenSSL 1.0+)
|
|
context.options |= getattr(_ssl, "OP_NO_COMPRESSION", 0)
|
|
|
|
if purpose == Purpose.SERVER_AUTH:
|
|
# verify certs and host name in client mode
|
|
context.verify_mode = CERT_REQUIRED
|
|
context.check_hostname = True
|
|
elif purpose == Purpose.CLIENT_AUTH:
|
|
# Prefer the server's ciphers by default so that we get stronger
|
|
# encryption
|
|
context.options |= getattr(_ssl, "OP_CIPHER_SERVER_PREFERENCE", 0)
|
|
|
|
# Use single use keys in order to improve forward secrecy
|
|
context.options |= getattr(_ssl, "OP_SINGLE_DH_USE", 0)
|
|
context.options |= getattr(_ssl, "OP_SINGLE_ECDH_USE", 0)
|
|
|
|
# disallow ciphers with known vulnerabilities
|
|
context.set_ciphers(_RESTRICTED_SERVER_CIPHERS)
|
|
|
|
if cafile or capath or cadata:
|
|
context.load_verify_locations(cafile, capath, cadata)
|
|
elif context.verify_mode != CERT_NONE:
|
|
# no explicit cafile, capath or cadata but the verify mode is
|
|
# CERT_OPTIONAL or CERT_REQUIRED. Let's try to load default system
|
|
# root CA certificates for the given purpose. This may fail silently.
|
|
context.load_default_certs(purpose)
|
|
return context
|
|
|
|
def _create_unverified_context(protocol=PROTOCOL_TLS, cert_reqs=None,
|
|
check_hostname=False, purpose=Purpose.SERVER_AUTH,
|
|
certfile=None, keyfile=None,
|
|
cafile=None, capath=None, cadata=None):
|
|
"""Create a SSLContext object for Python stdlib modules
|
|
|
|
All Python stdlib modules shall use this function to create SSLContext
|
|
objects in order to keep common settings in one place. The configuration
|
|
is less restrict than create_default_context()'s to increase backward
|
|
compatibility.
|
|
"""
|
|
if not isinstance(purpose, _ASN1Object):
|
|
raise TypeError(purpose)
|
|
|
|
context = SSLContext(protocol)
|
|
# SSLv2 considered harmful.
|
|
context.options |= OP_NO_SSLv2
|
|
# SSLv3 has problematic security and is only required for really old
|
|
# clients such as IE6 on Windows XP
|
|
context.options |= OP_NO_SSLv3
|
|
|
|
if cert_reqs is not None:
|
|
context.verify_mode = cert_reqs
|
|
context.check_hostname = check_hostname
|
|
|
|
if keyfile and not certfile:
|
|
raise ValueError("certfile must be specified")
|
|
if certfile or keyfile:
|
|
context.load_cert_chain(certfile, keyfile)
|
|
|
|
# load CA root certs
|
|
if cafile or capath or cadata:
|
|
context.load_verify_locations(cafile, capath, cadata)
|
|
elif context.verify_mode != CERT_NONE:
|
|
# no explicit cafile, capath or cadata but the verify mode is
|
|
# CERT_OPTIONAL or CERT_REQUIRED. Let's try to load default system
|
|
# root CA certificates for the given purpose. This may fail silently.
|
|
context.load_default_certs(purpose)
|
|
|
|
return context
|
|
|
|
# Backwards compatibility alias, even though it's not a public name.
|
|
_create_stdlib_context = _create_unverified_context
|
|
|
|
# PEP 493: Verify HTTPS by default, but allow envvar to override that
|
|
_https_verify_envvar = 'PYTHONHTTPSVERIFY'
|
|
|
|
def _get_https_context_factory():
|
|
if not sys.flags.ignore_environment:
|
|
config_setting = os.environ.get(_https_verify_envvar)
|
|
if config_setting == '0':
|
|
return _create_unverified_context
|
|
return create_default_context
|
|
|
|
_create_default_https_context = _get_https_context_factory()
|
|
|
|
# PEP 493: "private" API to configure HTTPS defaults without monkeypatching
|
|
def _https_verify_certificates(enable=True):
|
|
"""Verify server HTTPS certificates by default?"""
|
|
global _create_default_https_context
|
|
if enable:
|
|
_create_default_https_context = create_default_context
|
|
else:
|
|
_create_default_https_context = _create_unverified_context
|
|
|
|
|
|
class SSLSocket(socket):
|
|
"""This class implements a subtype of socket.socket that wraps
|
|
the underlying OS socket in an SSL context when necessary, and
|
|
provides read and write methods over that channel."""
|
|
|
|
def __init__(self, sock=None, keyfile=None, certfile=None,
|
|
server_side=False, cert_reqs=CERT_NONE,
|
|
ssl_version=PROTOCOL_TLS, ca_certs=None,
|
|
do_handshake_on_connect=True,
|
|
family=AF_INET, type=SOCK_STREAM, proto=0, fileno=None,
|
|
suppress_ragged_eofs=True, npn_protocols=None, ciphers=None,
|
|
server_hostname=None,
|
|
_context=None):
|
|
|
|
self._makefile_refs = 0
|
|
if _context:
|
|
self._context = _context
|
|
else:
|
|
if server_side and not certfile:
|
|
raise ValueError("certfile must be specified for server-side "
|
|
"operations")
|
|
if keyfile and not certfile:
|
|
raise ValueError("certfile must be specified")
|
|
if certfile and not keyfile:
|
|
keyfile = certfile
|
|
self._context = SSLContext(ssl_version)
|
|
self._context.verify_mode = cert_reqs
|
|
if ca_certs:
|
|
self._context.load_verify_locations(ca_certs)
|
|
if certfile:
|
|
self._context.load_cert_chain(certfile, keyfile)
|
|
if npn_protocols:
|
|
self._context.set_npn_protocols(npn_protocols)
|
|
if ciphers:
|
|
self._context.set_ciphers(ciphers)
|
|
self.keyfile = keyfile
|
|
self.certfile = certfile
|
|
self.cert_reqs = cert_reqs
|
|
self.ssl_version = ssl_version
|
|
self.ca_certs = ca_certs
|
|
self.ciphers = ciphers
|
|
# Can't use sock.type as other flags (such as SOCK_NONBLOCK) get
|
|
# mixed in.
|
|
if sock.getsockopt(SOL_SOCKET, SO_TYPE) != SOCK_STREAM:
|
|
raise NotImplementedError("only stream sockets are supported")
|
|
socket.__init__(self, _sock=sock._sock)
|
|
# The initializer for socket overrides the methods send(), recv(), etc.
|
|
# in the instancce, which we don't need -- but we want to provide the
|
|
# methods defined in SSLSocket.
|
|
for attr in _delegate_methods:
|
|
try:
|
|
delattr(self, attr)
|
|
except AttributeError:
|
|
pass
|
|
if server_side and server_hostname:
|
|
raise ValueError("server_hostname can only be specified "
|
|
"in client mode")
|
|
if self._context.check_hostname and not server_hostname:
|
|
raise ValueError("check_hostname requires server_hostname")
|
|
self.server_side = server_side
|
|
self.server_hostname = server_hostname
|
|
self.do_handshake_on_connect = do_handshake_on_connect
|
|
self.suppress_ragged_eofs = suppress_ragged_eofs
|
|
|
|
# See if we are connected
|
|
try:
|
|
self.getpeername()
|
|
except socket_error as e:
|
|
if e.errno != errno.ENOTCONN:
|
|
raise
|
|
connected = False
|
|
else:
|
|
connected = True
|
|
|
|
self._closed = False
|
|
self._sslobj = None
|
|
self._connected = connected
|
|
if connected:
|
|
# create the SSL object
|
|
try:
|
|
self._sslobj = self._context._wrap_socket(self._sock, server_side,
|
|
server_hostname, ssl_sock=self)
|
|
if do_handshake_on_connect:
|
|
timeout = self.gettimeout()
|
|
if timeout == 0.0:
|
|
# non-blocking
|
|
raise ValueError("do_handshake_on_connect should not be specified for non-blocking sockets")
|
|
self.do_handshake()
|
|
|
|
except (OSError, ValueError):
|
|
self.close()
|
|
raise
|
|
|
|
@property
|
|
def context(self):
|
|
return self._context
|
|
|
|
@context.setter
|
|
def context(self, ctx):
|
|
self._context = ctx
|
|
self._sslobj.context = ctx
|
|
|
|
def dup(self):
|
|
raise NotImplemented("Can't dup() %s instances" %
|
|
self.__class__.__name__)
|
|
|
|
def _checkClosed(self, msg=None):
|
|
# raise an exception here if you wish to check for spurious closes
|
|
pass
|
|
|
|
def _check_connected(self):
|
|
if not self._connected:
|
|
# getpeername() will raise ENOTCONN if the socket is really
|
|
# not connected; note that we can be connected even without
|
|
# _connected being set, e.g. if connect() first returned
|
|
# EAGAIN.
|
|
self.getpeername()
|
|
|
|
def read(self, len=1024, buffer=None):
|
|
"""Read up to LEN bytes and return them.
|
|
Return zero-length string on EOF."""
|
|
|
|
self._checkClosed()
|
|
if not self._sslobj:
|
|
raise ValueError("Read on closed or unwrapped SSL socket.")
|
|
try:
|
|
if buffer is not None:
|
|
v = self._sslobj.read(len, buffer)
|
|
else:
|
|
v = self._sslobj.read(len)
|
|
return v
|
|
except SSLError as x:
|
|
if x.args[0] == SSL_ERROR_EOF and self.suppress_ragged_eofs:
|
|
if buffer is not None:
|
|
return 0
|
|
else:
|
|
return b''
|
|
else:
|
|
raise
|
|
|
|
def write(self, data):
|
|
"""Write DATA to the underlying SSL channel. Returns
|
|
number of bytes of DATA actually transmitted."""
|
|
|
|
self._checkClosed()
|
|
if not self._sslobj:
|
|
raise ValueError("Write on closed or unwrapped SSL socket.")
|
|
return self._sslobj.write(data)
|
|
|
|
def getpeercert(self, binary_form=False):
|
|
"""Returns a formatted version of the data in the
|
|
certificate provided by the other end of the SSL channel.
|
|
Return None if no certificate was provided, {} if a
|
|
certificate was provided, but not validated."""
|
|
|
|
self._checkClosed()
|
|
self._check_connected()
|
|
return self._sslobj.peer_certificate(binary_form)
|
|
|
|
def selected_npn_protocol(self):
|
|
self._checkClosed()
|
|
if not self._sslobj or not _ssl.HAS_NPN:
|
|
return None
|
|
else:
|
|
return self._sslobj.selected_npn_protocol()
|
|
|
|
def selected_alpn_protocol(self):
|
|
self._checkClosed()
|
|
if not self._sslobj or not _ssl.HAS_ALPN:
|
|
return None
|
|
else:
|
|
return self._sslobj.selected_alpn_protocol()
|
|
|
|
def cipher(self):
|
|
self._checkClosed()
|
|
if not self._sslobj:
|
|
return None
|
|
else:
|
|
return self._sslobj.cipher()
|
|
|
|
def compression(self):
|
|
self._checkClosed()
|
|
if not self._sslobj:
|
|
return None
|
|
else:
|
|
return self._sslobj.compression()
|
|
|
|
def send(self, data, flags=0):
|
|
self._checkClosed()
|
|
if self._sslobj:
|
|
if flags != 0:
|
|
raise ValueError(
|
|
"non-zero flags not allowed in calls to send() on %s" %
|
|
self.__class__)
|
|
try:
|
|
v = self._sslobj.write(data)
|
|
except SSLError as x:
|
|
if x.args[0] == SSL_ERROR_WANT_READ:
|
|
return 0
|
|
elif x.args[0] == SSL_ERROR_WANT_WRITE:
|
|
return 0
|
|
else:
|
|
raise
|
|
else:
|
|
return v
|
|
else:
|
|
return self._sock.send(data, flags)
|
|
|
|
def sendto(self, data, flags_or_addr, addr=None):
|
|
self._checkClosed()
|
|
if self._sslobj:
|
|
raise ValueError("sendto not allowed on instances of %s" %
|
|
self.__class__)
|
|
elif addr is None:
|
|
return self._sock.sendto(data, flags_or_addr)
|
|
else:
|
|
return self._sock.sendto(data, flags_or_addr, addr)
|
|
|
|
|
|
def sendall(self, data, flags=0):
|
|
self._checkClosed()
|
|
if self._sslobj:
|
|
if flags != 0:
|
|
raise ValueError(
|
|
"non-zero flags not allowed in calls to sendall() on %s" %
|
|
self.__class__)
|
|
amount = len(data)
|
|
count = 0
|
|
while (count < amount):
|
|
v = self.send(data[count:])
|
|
count += v
|
|
return amount
|
|
else:
|
|
return socket.sendall(self, data, flags)
|
|
|
|
def recv(self, buflen=1024, flags=0):
|
|
self._checkClosed()
|
|
if self._sslobj:
|
|
if flags != 0:
|
|
raise ValueError(
|
|
"non-zero flags not allowed in calls to recv() on %s" %
|
|
self.__class__)
|
|
return self.read(buflen)
|
|
else:
|
|
return self._sock.recv(buflen, flags)
|
|
|
|
def recv_into(self, buffer, nbytes=None, flags=0):
|
|
self._checkClosed()
|
|
if buffer and (nbytes is None):
|
|
nbytes = len(buffer)
|
|
elif nbytes is None:
|
|
nbytes = 1024
|
|
if self._sslobj:
|
|
if flags != 0:
|
|
raise ValueError(
|
|
"non-zero flags not allowed in calls to recv_into() on %s" %
|
|
self.__class__)
|
|
return self.read(nbytes, buffer)
|
|
else:
|
|
return self._sock.recv_into(buffer, nbytes, flags)
|
|
|
|
def recvfrom(self, buflen=1024, flags=0):
|
|
self._checkClosed()
|
|
if self._sslobj:
|
|
raise ValueError("recvfrom not allowed on instances of %s" %
|
|
self.__class__)
|
|
else:
|
|
return self._sock.recvfrom(buflen, flags)
|
|
|
|
def recvfrom_into(self, buffer, nbytes=None, flags=0):
|
|
self._checkClosed()
|
|
if self._sslobj:
|
|
raise ValueError("recvfrom_into not allowed on instances of %s" %
|
|
self.__class__)
|
|
else:
|
|
return self._sock.recvfrom_into(buffer, nbytes, flags)
|
|
|
|
|
|
def pending(self):
|
|
self._checkClosed()
|
|
if self._sslobj:
|
|
return self._sslobj.pending()
|
|
else:
|
|
return 0
|
|
|
|
def shutdown(self, how):
|
|
self._checkClosed()
|
|
self._sslobj = None
|
|
socket.shutdown(self, how)
|
|
|
|
def close(self):
|
|
if self._makefile_refs < 1:
|
|
self._sslobj = None
|
|
socket.close(self)
|
|
else:
|
|
self._makefile_refs -= 1
|
|
|
|
def unwrap(self):
|
|
if self._sslobj:
|
|
s = self._sslobj.shutdown()
|
|
self._sslobj = None
|
|
return s
|
|
else:
|
|
raise ValueError("No SSL wrapper around " + str(self))
|
|
|
|
def _real_close(self):
|
|
self._sslobj = None
|
|
socket._real_close(self)
|
|
|
|
def do_handshake(self, block=False):
|
|
"""Perform a TLS/SSL handshake."""
|
|
self._check_connected()
|
|
timeout = self.gettimeout()
|
|
try:
|
|
if timeout == 0.0 and block:
|
|
self.settimeout(None)
|
|
self._sslobj.do_handshake()
|
|
finally:
|
|
self.settimeout(timeout)
|
|
|
|
if self.context.check_hostname:
|
|
if not self.server_hostname:
|
|
raise ValueError("check_hostname needs server_hostname "
|
|
"argument")
|
|
match_hostname(self.getpeercert(), self.server_hostname)
|
|
|
|
def _real_connect(self, addr, connect_ex):
|
|
if self.server_side:
|
|
raise ValueError("can't connect in server-side mode")
|
|
# Here we assume that the socket is client-side, and not
|
|
# connected at the time of the call. We connect it, then wrap it.
|
|
if self._connected:
|
|
raise ValueError("attempt to connect already-connected SSLSocket!")
|
|
self._sslobj = self.context._wrap_socket(self._sock, False, self.server_hostname, ssl_sock=self)
|
|
try:
|
|
if connect_ex:
|
|
rc = socket.connect_ex(self, addr)
|
|
else:
|
|
rc = None
|
|
socket.connect(self, addr)
|
|
if not rc:
|
|
self._connected = True
|
|
if self.do_handshake_on_connect:
|
|
self.do_handshake()
|
|
return rc
|
|
except (OSError, ValueError):
|
|
self._sslobj = None
|
|
raise
|
|
|
|
def connect(self, addr):
|
|
"""Connects to remote ADDR, and then wraps the connection in
|
|
an SSL channel."""
|
|
self._real_connect(addr, False)
|
|
|
|
def connect_ex(self, addr):
|
|
"""Connects to remote ADDR, and then wraps the connection in
|
|
an SSL channel."""
|
|
return self._real_connect(addr, True)
|
|
|
|
def accept(self):
|
|
"""Accepts a new connection from a remote client, and returns
|
|
a tuple containing that new connection wrapped with a server-side
|
|
SSL channel, and the address of the remote client."""
|
|
|
|
newsock, addr = socket.accept(self)
|
|
newsock = self.context.wrap_socket(newsock,
|
|
do_handshake_on_connect=self.do_handshake_on_connect,
|
|
suppress_ragged_eofs=self.suppress_ragged_eofs,
|
|
server_side=True)
|
|
return newsock, addr
|
|
|
|
def makefile(self, mode='r', bufsize=-1):
|
|
|
|
"""Make and return a file-like object that
|
|
works with the SSL connection. Just use the code
|
|
from the socket module."""
|
|
|
|
self._makefile_refs += 1
|
|
# close=True so as to decrement the reference count when done with
|
|
# the file-like object.
|
|
return _fileobject(self, mode, bufsize, close=True)
|
|
|
|
def get_channel_binding(self, cb_type="tls-unique"):
|
|
"""Get channel binding data for current connection. Raise ValueError
|
|
if the requested `cb_type` is not supported. Return bytes of the data
|
|
or None if the data is not available (e.g. before the handshake).
|
|
"""
|
|
if cb_type not in CHANNEL_BINDING_TYPES:
|
|
raise ValueError("Unsupported channel binding type")
|
|
if cb_type != "tls-unique":
|
|
raise NotImplementedError(
|
|
"{0} channel binding type not implemented"
|
|
.format(cb_type))
|
|
if self._sslobj is None:
|
|
return None
|
|
return self._sslobj.tls_unique_cb()
|
|
|
|
def version(self):
|
|
"""
|
|
Return a string identifying the protocol version used by the
|
|
current SSL channel, or None if there is no established channel.
|
|
"""
|
|
if self._sslobj is None:
|
|
return None
|
|
return self._sslobj.version()
|
|
|
|
|
|
def wrap_socket(sock, keyfile=None, certfile=None,
|
|
server_side=False, cert_reqs=CERT_NONE,
|
|
ssl_version=PROTOCOL_TLS, ca_certs=None,
|
|
do_handshake_on_connect=True,
|
|
suppress_ragged_eofs=True,
|
|
ciphers=None):
|
|
|
|
return SSLSocket(sock=sock, keyfile=keyfile, certfile=certfile,
|
|
server_side=server_side, cert_reqs=cert_reqs,
|
|
ssl_version=ssl_version, ca_certs=ca_certs,
|
|
do_handshake_on_connect=do_handshake_on_connect,
|
|
suppress_ragged_eofs=suppress_ragged_eofs,
|
|
ciphers=ciphers)
|
|
|
|
# some utility functions
|
|
|
|
def cert_time_to_seconds(cert_time):
|
|
"""Return the time in seconds since the Epoch, given the timestring
|
|
representing the "notBefore" or "notAfter" date from a certificate
|
|
in ``"%b %d %H:%M:%S %Y %Z"`` strptime format (C locale).
|
|
|
|
"notBefore" or "notAfter" dates must use UTC (RFC 5280).
|
|
|
|
Month is one of: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
|
|
UTC should be specified as GMT (see ASN1_TIME_print())
|
|
"""
|
|
from time import strptime
|
|
from calendar import timegm
|
|
|
|
months = (
|
|
"Jan","Feb","Mar","Apr","May","Jun",
|
|
"Jul","Aug","Sep","Oct","Nov","Dec"
|
|
)
|
|
time_format = ' %d %H:%M:%S %Y GMT' # NOTE: no month, fixed GMT
|
|
try:
|
|
month_number = months.index(cert_time[:3].title()) + 1
|
|
except ValueError:
|
|
raise ValueError('time data %r does not match '
|
|
'format "%%b%s"' % (cert_time, time_format))
|
|
else:
|
|
# found valid month
|
|
tt = strptime(cert_time[3:], time_format)
|
|
# return an integer, the previous mktime()-based implementation
|
|
# returned a float (fractional seconds are always zero here).
|
|
return timegm((tt[0], month_number) + tt[2:6])
|
|
|
|
PEM_HEADER = "-----BEGIN CERTIFICATE-----"
|
|
PEM_FOOTER = "-----END CERTIFICATE-----"
|
|
|
|
def DER_cert_to_PEM_cert(der_cert_bytes):
|
|
"""Takes a certificate in binary DER format and returns the
|
|
PEM version of it as a string."""
|
|
|
|
f = base64.standard_b64encode(der_cert_bytes).decode('ascii')
|
|
return (PEM_HEADER + '\n' +
|
|
textwrap.fill(f, 64) + '\n' +
|
|
PEM_FOOTER + '\n')
|
|
|
|
def PEM_cert_to_DER_cert(pem_cert_string):
|
|
"""Takes a certificate in ASCII PEM format and returns the
|
|
DER-encoded version of it as a byte sequence"""
|
|
|
|
if not pem_cert_string.startswith(PEM_HEADER):
|
|
raise ValueError("Invalid PEM encoding; must start with %s"
|
|
% PEM_HEADER)
|
|
if not pem_cert_string.strip().endswith(PEM_FOOTER):
|
|
raise ValueError("Invalid PEM encoding; must end with %s"
|
|
% PEM_FOOTER)
|
|
d = pem_cert_string.strip()[len(PEM_HEADER):-len(PEM_FOOTER)]
|
|
return base64.decodestring(d.encode('ASCII', 'strict'))
|
|
|
|
def get_server_certificate(addr, ssl_version=PROTOCOL_TLS, ca_certs=None):
|
|
"""Retrieve the certificate from the server at the specified address,
|
|
and return it as a PEM-encoded string.
|
|
If 'ca_certs' is specified, validate the server cert against it.
|
|
If 'ssl_version' is specified, use it in the connection attempt."""
|
|
|
|
host, port = addr
|
|
if ca_certs is not None:
|
|
cert_reqs = CERT_REQUIRED
|
|
else:
|
|
cert_reqs = CERT_NONE
|
|
context = _create_stdlib_context(ssl_version,
|
|
cert_reqs=cert_reqs,
|
|
cafile=ca_certs)
|
|
with closing(create_connection(addr)) as sock:
|
|
with closing(context.wrap_socket(sock)) as sslsock:
|
|
dercert = sslsock.getpeercert(True)
|
|
return DER_cert_to_PEM_cert(dercert)
|
|
|
|
def get_protocol_name(protocol_code):
|
|
return _PROTOCOL_NAMES.get(protocol_code, '<unknown>')
|
|
|
|
|
|
# a replacement for the old socket.ssl function
|
|
|
|
def sslwrap_simple(sock, keyfile=None, certfile=None):
|
|
"""A replacement for the old socket.ssl function. Designed
|
|
for compability with Python 2.5 and earlier. Will disappear in
|
|
Python 3.0."""
|
|
if hasattr(sock, "_sock"):
|
|
sock = sock._sock
|
|
|
|
ctx = SSLContext(PROTOCOL_SSLv23)
|
|
if keyfile or certfile:
|
|
ctx.load_cert_chain(certfile, keyfile)
|
|
ssl_sock = ctx._wrap_socket(sock, server_side=False)
|
|
try:
|
|
sock.getpeername()
|
|
except socket_error:
|
|
# no, no connection yet
|
|
pass
|
|
else:
|
|
# yes, do the handshake
|
|
ssl_sock.do_handshake()
|
|
|
|
return ssl_sock
|
|
|