946 lines
34 KiB
Python
946 lines
34 KiB
Python
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# 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_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 enum import Enum as _Enum
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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 (VERIFY_DEFAULT, VERIFY_CRL_CHECK_LEAF, VERIFY_CRL_CHECK_CHAIN,
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VERIFY_X509_STRICT)
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from _ssl import txt2obj as _txt2obj, nid2obj as _nid2obj
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from _ssl import RAND_status, RAND_egd, RAND_add, RAND_bytes, RAND_pseudo_bytes
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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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from _ssl import HAS_SNI, HAS_ECDH, HAS_NPN
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from _ssl import PROTOCOL_SSLv3, PROTOCOL_SSLv23, PROTOCOL_TLSv1
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from _ssl import _OPENSSL_API_VERSION
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_PROTOCOL_NAMES = {
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PROTOCOL_TLSv1: "TLSv1",
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PROTOCOL_SSLv23: "SSLv23",
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PROTOCOL_SSLv3: "SSLv3",
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}
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try:
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from _ssl import PROTOCOL_SSLv2
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_SSLv2_IF_EXISTS = PROTOCOL_SSLv2
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except ImportError:
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_SSLv2_IF_EXISTS = None
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else:
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_PROTOCOL_NAMES[PROTOCOL_SSLv2] = "SSLv2"
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try:
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from _ssl import PROTOCOL_TLSv1_1, PROTOCOL_TLSv1_2
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except ImportError:
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pass
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else:
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_PROTOCOL_NAMES[PROTOCOL_TLSv1_1] = "TLSv1.1"
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_PROTOCOL_NAMES[PROTOCOL_TLSv1_2] = "TLSv1.2"
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if sys.platform == "win32":
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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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socket_error = OSError # keep that public name in module namespace
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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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# * 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 any AES-GCM over any AES-CBC for better performance and security
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# * Then Use HIGH cipher suites as a fallback
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# * Then Use 3DES as fallback which is secure but slow
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# * Finally use RC4 as a fallback which is problematic but needed for
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# compatibility some times.
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# * Disable NULL authentication, NULL encryption, and MD5 MACs for security
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# reasons
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_DEFAULT_CIPHERS = (
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'ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:ECDH+HIGH:'
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'DH+HIGH:ECDH+3DES:DH+3DES:RSA+AESGCM:RSA+AES:RSA+HIGH:RSA+3DES:ECDH+RC4:'
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'DH+RC4:RSA+RC4:!aNULL:!eNULL:!MD5'
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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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# * 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 any AES-GCM over any AES-CBC for better performance and security
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# * Then Use HIGH cipher suites as a fallback
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# * Then Use 3DES as fallback which is secure but slow
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# * Disable NULL authentication, NULL encryption, MD5 MACs, DSS, and RC4 for
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# security reasons
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_RESTRICTED_SERVER_CIPHERS = (
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'ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:ECDH+HIGH:'
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'DH+HIGH:ECDH+3DES:DH+3DES:RSA+AESGCM:RSA+AES:RSA+HIGH:RSA+3DES:!aNULL:'
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'!eNULL:!MD5:!DSS:!RC4'
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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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leftmost, *remainder = dn.split(r'.')
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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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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().__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().__new__(cls, *_nid2obj(nid))
|
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|
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@classmethod
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||
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def fromname(cls, name):
|
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|
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"""Create _ASN1Object from short name, long name or OID
|
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"""
|
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return super().__new__(cls, *_txt2obj(name, name=True))
|
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|
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class Purpose(_ASN1Object, _Enum):
|
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|
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"""SSLContext purpose flags with X509v3 Extended Key Usage objects
|
||
|
|
"""
|
||
|
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SERVER_AUTH = '1.3.6.1.5.5.7.3.1'
|
||
|
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CLIENT_AUTH = '1.3.6.1.5.5.7.3.2'
|
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|
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|
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|
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|
||
|
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class SSLContext(_SSLContext):
|
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|
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"""An SSLContext holds various SSL-related configuration options and
|
||
|
|
data, such as certificates and possibly a private key."""
|
||
|
|
|
||
|
|
__slots__ = ('protocol', '__weakref__')
|
||
|
|
_windows_cert_stores = ("CA", "ROOT")
|
||
|
|
|
||
|
|
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,
|
||
|
|
do_handshake_on_connect=True,
|
||
|
|
suppress_ragged_eofs=True,
|
||
|
|
server_hostname=None):
|
||
|
|
return SSLSocket(sock=sock, server_side=server_side,
|
||
|
|
do_handshake_on_connect=do_handshake_on_connect,
|
||
|
|
suppress_ragged_eofs=suppress_ragged_eofs,
|
||
|
|
server_hostname=server_hostname,
|
||
|
|
_context=self)
|
||
|
|
|
||
|
|
def set_npn_protocols(self, npn_protocols):
|
||
|
|
protos = bytearray()
|
||
|
|
for protocol in npn_protocols:
|
||
|
|
b = bytes(protocol, 'ascii')
|
||
|
|
if len(b) == 0 or len(b) > 255:
|
||
|
|
raise SSLError('NPN protocols must be 1 to 255 in length')
|
||
|
|
protos.append(len(b))
|
||
|
|
protos.extend(b)
|
||
|
|
|
||
|
|
self._set_npn_protocols(protos)
|
||
|
|
|
||
|
|
def _load_windows_store_certs(self, storename, purpose):
|
||
|
|
certs = bytearray()
|
||
|
|
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)
|
||
|
|
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":
|
||
|
|
for storename in self._windows_cert_stores:
|
||
|
|
self._load_windows_store_certs(storename, purpose)
|
||
|
|
else:
|
||
|
|
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_SSLv23)
|
||
|
|
|
||
|
|
# 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_stdlib_context(protocol=PROTOCOL_SSLv23, *, 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
|
||
|
|
|
||
|
|
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
|
||
|
|
|
||
|
|
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_SSLv23, 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):
|
||
|
|
|
||
|
|
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")
|
||
|
|
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:
|
||
|
|
if HAS_SNI:
|
||
|
|
raise ValueError("check_hostname requires server_hostname")
|
||
|
|
else:
|
||
|
|
raise ValueError("check_hostname requires server_hostname, "
|
||
|
|
"but it's not supported by your OpenSSL "
|
||
|
|
"library")
|
||
|
|
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
|
||
|
|
if sock is not None:
|
||
|
|
socket.__init__(self,
|
||
|
|
family=sock.family,
|
||
|
|
type=sock.type,
|
||
|
|
proto=sock.proto,
|
||
|
|
fileno=sock.fileno())
|
||
|
|
self.settimeout(sock.gettimeout())
|
||
|
|
sock.detach()
|
||
|
|
elif fileno is not None:
|
||
|
|
socket.__init__(self, fileno=fileno)
|
||
|
|
else:
|
||
|
|
socket.__init__(self, family=family, type=type, proto=proto)
|
||
|
|
|
||
|
|
# See if we are connected
|
||
|
|
try:
|
||
|
|
self.getpeername()
|
||
|
|
except OSError 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, server_side,
|
||
|
|
server_hostname)
|
||
|
|
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=0, 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 or 1024)
|
||
|
|
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 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 socket.send(self, 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 socket.sendto(self, data, flags_or_addr)
|
||
|
|
else:
|
||
|
|
return socket.sendto(self, data, flags_or_addr, addr)
|
||
|
|
|
||
|
|
def sendmsg(self, *args, **kwargs):
|
||
|
|
# Ensure programs don't send data unencrypted if they try to
|
||
|
|
# use this method.
|
||
|
|
raise NotImplementedError("sendmsg not allowed on instances of %s" %
|
||
|
|
self.__class__)
|
||
|
|
|
||
|
|
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 socket.recv(self, 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 socket.recv_into(self, 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 socket.recvfrom(self, 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 socket.recvfrom_into(self, buffer, nbytes, flags)
|
||
|
|
|
||
|
|
def recvmsg(self, *args, **kwargs):
|
||
|
|
raise NotImplementedError("recvmsg not allowed on instances of %s" %
|
||
|
|
self.__class__)
|
||
|
|
|
||
|
|
def recvmsg_into(self, *args, **kwargs):
|
||
|
|
raise NotImplementedError("recvmsg_into not allowed on instances of "
|
||
|
|
"%s" % self.__class__)
|
||
|
|
|
||
|
|
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 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, False, self.server_hostname)
|
||
|
|
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 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 wrap_socket(sock, keyfile=None, certfile=None,
|
||
|
|
server_side=False, cert_reqs=CERT_NONE,
|
||
|
|
ssl_version=PROTOCOL_SSLv23, 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):
|
||
|
|
"""Takes a date-time string in standard ASN1_print form
|
||
|
|
("MON DAY 24HOUR:MINUTE:SEC YEAR TIMEZONE") and return
|
||
|
|
a Python time value in seconds past the epoch."""
|
||
|
|
|
||
|
|
import time
|
||
|
|
return time.mktime(time.strptime(cert_time, "%b %d %H:%M:%S %Y GMT"))
|
||
|
|
|
||
|
|
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 = str(base64.standard_b64encode(der_cert_bytes), 'ASCII', 'strict')
|
||
|
|
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.decodebytes(d.encode('ASCII', 'strict'))
|
||
|
|
|
||
|
|
def get_server_certificate(addr, ssl_version=PROTOCOL_SSLv3, 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 create_connection(addr) as sock:
|
||
|
|
with 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>')
|