1303 lines
44 KiB
Python
1303 lines
44 KiB
Python
# 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_TLS_CLIENT
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PROTOCOL_TLS_SERVER
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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 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, IntEnum as _IntEnum, IntFlag as _IntFlag
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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, MemoryBIO, SSLSession
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from _ssl import (
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SSLError, SSLZeroReturnError, SSLWantReadError, SSLWantWriteError,
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SSLSyscallError, SSLEOFError, SSLCertVerificationError
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)
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from _ssl import txt2obj as _txt2obj, nid2obj as _nid2obj
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from _ssl import RAND_status, RAND_add, RAND_bytes, RAND_pseudo_bytes
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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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from _ssl import (
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HAS_SNI, HAS_ECDH, HAS_NPN, HAS_ALPN, HAS_SSLv2, HAS_SSLv3, HAS_TLSv1,
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HAS_TLSv1_1, HAS_TLSv1_2, HAS_TLSv1_3
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)
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from _ssl import _DEFAULT_CIPHERS, _OPENSSL_API_VERSION
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_IntEnum._convert(
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'_SSLMethod', __name__,
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lambda name: name.startswith('PROTOCOL_') and name != 'PROTOCOL_SSLv23',
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source=_ssl)
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_IntFlag._convert(
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'Options', __name__,
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lambda name: name.startswith('OP_'),
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source=_ssl)
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_IntEnum._convert(
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'AlertDescription', __name__,
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lambda name: name.startswith('ALERT_DESCRIPTION_'),
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source=_ssl)
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_IntEnum._convert(
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'SSLErrorNumber', __name__,
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lambda name: name.startswith('SSL_ERROR_'),
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source=_ssl)
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_IntFlag._convert(
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'VerifyFlags', __name__,
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lambda name: name.startswith('VERIFY_'),
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source=_ssl)
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_IntEnum._convert(
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'VerifyMode', __name__,
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lambda name: name.startswith('CERT_'),
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source=_ssl)
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PROTOCOL_SSLv23 = _SSLMethod.PROTOCOL_SSLv23 = _SSLMethod.PROTOCOL_TLS
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_PROTOCOL_NAMES = {value: name for name, value in _SSLMethod.__members__.items()}
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_SSLv2_IF_EXISTS = getattr(_SSLMethod, 'PROTOCOL_SSLv2', None)
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class TLSVersion(_IntEnum):
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MINIMUM_SUPPORTED = _ssl.PROTO_MINIMUM_SUPPORTED
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SSLv3 = _ssl.PROTO_SSLv3
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TLSv1 = _ssl.PROTO_TLSv1
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TLSv1_1 = _ssl.PROTO_TLSv1_1
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TLSv1_2 = _ssl.PROTO_TLSv1_2
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TLSv1_3 = _ssl.PROTO_TLSv1_3
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MAXIMUM_SUPPORTED = _ssl.PROTO_MAXIMUM_SUPPORTED
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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 socket as _socket
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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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socket_error = OSError # keep that public name in module namespace
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CHANNEL_BINDING_TYPES = ['tls-unique']
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HAS_NEVER_CHECK_COMMON_NAME = hasattr(_ssl, 'HOSTFLAG_NEVER_CHECK_SUBJECT')
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_RESTRICTED_SERVER_CIPHERS = _DEFAULT_CIPHERS
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CertificateError = SSLCertVerificationError
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def _dnsname_match(dn, hostname):
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"""Matching according to RFC 6125, section 6.4.3
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- Hostnames are compared lower case.
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- For IDNA, both dn and hostname must be encoded as IDN A-label (ACE).
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- Partial wildcards like 'www*.example.org', multiple wildcards, sole
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wildcard or wildcards in labels other then the left-most label are not
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supported and a CertificateError is raised.
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- A wildcard must match at least one character.
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"""
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if not dn:
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return False
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wildcards = dn.count('*')
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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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if wildcards > 1:
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raise CertificateError(
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"too many wildcards in certificate DNS name: {!r}.".format(dn))
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dn_leftmost, sep, dn_remainder = dn.partition('.')
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if '*' in dn_remainder:
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# Only match wildcard in leftmost segment.
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raise CertificateError(
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"wildcard can only be present in the leftmost label: "
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"{!r}.".format(dn))
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if not sep:
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# no right side
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raise CertificateError(
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"sole wildcard without additional labels are not support: "
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"{!r}.".format(dn))
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if dn_leftmost != '*':
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# no partial wildcard matching
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raise CertificateError(
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"partial wildcards in leftmost label are not supported: "
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"{!r}.".format(dn))
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hostname_leftmost, sep, hostname_remainder = hostname.partition('.')
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if not hostname_leftmost or not sep:
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# wildcard must match at least one char
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return False
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return dn_remainder.lower() == hostname_remainder.lower()
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def _inet_paton(ipname):
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"""Try to convert an IP address to packed binary form
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Supports IPv4 addresses on all platforms and IPv6 on platforms with IPv6
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support.
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"""
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# inet_aton() also accepts strings like '1'
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if ipname.count('.') == 3:
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try:
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return _socket.inet_aton(ipname)
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except OSError:
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pass
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try:
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return _socket.inet_pton(_socket.AF_INET6, ipname)
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except OSError:
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raise ValueError("{!r} is neither an IPv4 nor an IP6 "
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"address.".format(ipname))
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except AttributeError:
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# AF_INET6 not available
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pass
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raise ValueError("{!r} is not an IPv4 address.".format(ipname))
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def _ipaddress_match(ipname, host_ip):
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"""Exact matching of IP addresses.
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RFC 6125 explicitly doesn't define an algorithm for this
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(section 1.7.2 - "Out of Scope").
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"""
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# OpenSSL may add a trailing newline to a subjectAltName's IP address
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ip = _inet_paton(ipname.rstrip())
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return ip == host_ip
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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.
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The function matches IP addresses rather than dNSNames if hostname is a
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valid ipaddress string. IPv4 addresses are supported on all platforms.
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IPv6 addresses are supported on platforms with IPv6 support (AF_INET6
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and inet_pton).
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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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try:
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host_ip = _inet_paton(hostname)
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except ValueError:
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# Not an IP address (common case)
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host_ip = None
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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 host_ip is None and _dnsname_match(value, hostname):
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return
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dnsnames.append(value)
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elif key == 'IP Address':
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if host_ip is not None and _ipaddress_match(value, host_ip):
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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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@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().__new__(cls, *_txt2obj(name, name=True))
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class Purpose(_ASN1Object, _Enum):
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"""SSLContext purpose flags with X509v3 Extended Key Usage objects
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"""
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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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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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_windows_cert_stores = ("CA", "ROOT")
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sslsocket_class = None # SSLSocket is assigned later.
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sslobject_class = None # SSLObject is assigned later.
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def __new__(cls, protocol=PROTOCOL_TLS, *args, **kwargs):
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self = _SSLContext.__new__(cls, protocol)
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return self
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def _encode_hostname(self, hostname):
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if hostname is None:
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return None
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elif isinstance(hostname, str):
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return hostname.encode('idna').decode('ascii')
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else:
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return hostname.decode('ascii')
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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, session=None):
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# SSLSocket class handles server_hostname encoding before it calls
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# ctx._wrap_socket()
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return self.sslsocket_class._create(
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sock=sock,
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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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session=session
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)
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def wrap_bio(self, incoming, outgoing, server_side=False,
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server_hostname=None, session=None):
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# Need to encode server_hostname here because _wrap_bio() can only
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# handle ASCII str.
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return self.sslobject_class._create(
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incoming, outgoing, server_side=server_side,
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server_hostname=self._encode_hostname(server_hostname),
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session=session, context=self,
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)
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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 = bytes(protocol, '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_servername_callback(self, server_name_callback):
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if server_name_callback is None:
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self.sni_callback = None
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else:
|
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if not callable(server_name_callback):
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raise TypeError("not a callable object")
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|
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def shim_cb(sslobj, servername, sslctx):
|
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servername = self._encode_hostname(servername)
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return server_name_callback(sslobj, servername, sslctx)
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self.sni_callback = shim_cb
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|
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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 = bytes(protocol, '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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self._set_alpn_protocols(protos)
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|
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def _load_windows_store_certs(self, storename, purpose):
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certs = bytearray()
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try:
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for cert, encoding, trust in enum_certificates(storename):
|
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# CA certs are never PKCS#7 encoded
|
|
if encoding == "x509_asn":
|
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if trust is True or purpose.oid in trust:
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certs.extend(cert)
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except PermissionError:
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warnings.warn("unable to enumerate Windows certificate store")
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if certs:
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self.load_verify_locations(cadata=certs)
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return certs
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|
|
def load_default_certs(self, purpose=Purpose.SERVER_AUTH):
|
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if not isinstance(purpose, _ASN1Object):
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raise TypeError(purpose)
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if sys.platform == "win32":
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for storename in self._windows_cert_stores:
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self._load_windows_store_certs(storename, purpose)
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self.set_default_verify_paths()
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|
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if hasattr(_SSLContext, 'minimum_version'):
|
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@property
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def minimum_version(self):
|
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return TLSVersion(super().minimum_version)
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|
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@minimum_version.setter
|
|
def minimum_version(self, value):
|
|
if value == TLSVersion.SSLv3:
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self.options &= ~Options.OP_NO_SSLv3
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super(SSLContext, SSLContext).minimum_version.__set__(self, value)
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|
|
@property
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|
def maximum_version(self):
|
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return TLSVersion(super().maximum_version)
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|
|
@maximum_version.setter
|
|
def maximum_version(self, value):
|
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super(SSLContext, SSLContext).maximum_version.__set__(self, value)
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|
|
@property
|
|
def options(self):
|
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return Options(super().options)
|
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|
|
@options.setter
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|
def options(self, value):
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super(SSLContext, SSLContext).options.__set__(self, value)
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|
|
if hasattr(_ssl, 'HOSTFLAG_NEVER_CHECK_SUBJECT'):
|
|
@property
|
|
def hostname_checks_common_name(self):
|
|
ncs = self._host_flags & _ssl.HOSTFLAG_NEVER_CHECK_SUBJECT
|
|
return ncs != _ssl.HOSTFLAG_NEVER_CHECK_SUBJECT
|
|
|
|
@hostname_checks_common_name.setter
|
|
def hostname_checks_common_name(self, value):
|
|
if value:
|
|
self._host_flags &= ~_ssl.HOSTFLAG_NEVER_CHECK_SUBJECT
|
|
else:
|
|
self._host_flags |= _ssl.HOSTFLAG_NEVER_CHECK_SUBJECT
|
|
else:
|
|
@property
|
|
def hostname_checks_common_name(self):
|
|
return True
|
|
|
|
@property
|
|
def protocol(self):
|
|
return _SSLMethod(super().protocol)
|
|
|
|
@property
|
|
def verify_flags(self):
|
|
return VerifyFlags(super().verify_flags)
|
|
|
|
@verify_flags.setter
|
|
def verify_flags(self, value):
|
|
super(SSLContext, SSLContext).verify_flags.__set__(self, value)
|
|
|
|
@property
|
|
def verify_mode(self):
|
|
value = super().verify_mode
|
|
try:
|
|
return VerifyMode(value)
|
|
except ValueError:
|
|
return value
|
|
|
|
@verify_mode.setter
|
|
def verify_mode(self, value):
|
|
super(SSLContext, SSLContext).verify_mode.__set__(self, value)
|
|
|
|
|
|
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)
|
|
|
|
# SSLContext sets OP_NO_SSLv2, OP_NO_SSLv3, OP_NO_COMPRESSION,
|
|
# OP_CIPHER_SERVER_PREFERENCE, OP_SINGLE_DH_USE and OP_SINGLE_ECDH_USE
|
|
# by default.
|
|
context = SSLContext(PROTOCOL_TLS)
|
|
|
|
if purpose == Purpose.SERVER_AUTH:
|
|
# verify certs and host name in client mode
|
|
context.verify_mode = CERT_REQUIRED
|
|
context.check_hostname = True
|
|
|
|
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=CERT_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)
|
|
|
|
# SSLContext sets OP_NO_SSLv2, OP_NO_SSLv3, OP_NO_COMPRESSION,
|
|
# OP_CIPHER_SERVER_PREFERENCE, OP_SINGLE_DH_USE and OP_SINGLE_ECDH_USE
|
|
# by default.
|
|
context = SSLContext(protocol)
|
|
|
|
if not check_hostname:
|
|
context.check_hostname = False
|
|
if cert_reqs is not None:
|
|
context.verify_mode = cert_reqs
|
|
if check_hostname:
|
|
context.check_hostname = True
|
|
|
|
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
|
|
|
|
# Used by http.client if no context is explicitly passed.
|
|
_create_default_https_context = create_default_context
|
|
|
|
|
|
# Backwards compatibility alias, even though it's not a public name.
|
|
_create_stdlib_context = _create_unverified_context
|
|
|
|
|
|
class SSLObject:
|
|
"""This class implements an interface on top of a low-level SSL object as
|
|
implemented by OpenSSL. This object captures the state of an SSL connection
|
|
but does not provide any network IO itself. IO needs to be performed
|
|
through separate "BIO" objects which are OpenSSL's IO abstraction layer.
|
|
|
|
This class does not have a public constructor. Instances are returned by
|
|
``SSLContext.wrap_bio``. This class is typically used by framework authors
|
|
that want to implement asynchronous IO for SSL through memory buffers.
|
|
|
|
When compared to ``SSLSocket``, this object lacks the following features:
|
|
|
|
* Any form of network IO, including methods such as ``recv`` and ``send``.
|
|
* The ``do_handshake_on_connect`` and ``suppress_ragged_eofs`` machinery.
|
|
"""
|
|
def __init__(self, *args, **kwargs):
|
|
raise TypeError(
|
|
f"{self.__class__.__name__} does not have a public "
|
|
f"constructor. Instances are returned by SSLContext.wrap_bio()."
|
|
)
|
|
|
|
@classmethod
|
|
def _create(cls, incoming, outgoing, server_side=False,
|
|
server_hostname=None, session=None, context=None):
|
|
self = cls.__new__(cls)
|
|
sslobj = context._wrap_bio(
|
|
incoming, outgoing, server_side=server_side,
|
|
server_hostname=server_hostname,
|
|
owner=self, session=session
|
|
)
|
|
self._sslobj = sslobj
|
|
return self
|
|
|
|
@property
|
|
def context(self):
|
|
"""The SSLContext that is currently in use."""
|
|
return self._sslobj.context
|
|
|
|
@context.setter
|
|
def context(self, ctx):
|
|
self._sslobj.context = ctx
|
|
|
|
@property
|
|
def session(self):
|
|
"""The SSLSession for client socket."""
|
|
return self._sslobj.session
|
|
|
|
@session.setter
|
|
def session(self, session):
|
|
self._sslobj.session = session
|
|
|
|
@property
|
|
def session_reused(self):
|
|
"""Was the client session reused during handshake"""
|
|
return self._sslobj.session_reused
|
|
|
|
@property
|
|
def server_side(self):
|
|
"""Whether this is a server-side socket."""
|
|
return self._sslobj.server_side
|
|
|
|
@property
|
|
def server_hostname(self):
|
|
"""The currently set server hostname (for SNI), or ``None`` if no
|
|
server hostame is set."""
|
|
return self._sslobj.server_hostname
|
|
|
|
def read(self, len=1024, buffer=None):
|
|
"""Read up to 'len' bytes from the SSL object and return them.
|
|
|
|
If 'buffer' is provided, read into this buffer and return the number of
|
|
bytes read.
|
|
"""
|
|
if buffer is not None:
|
|
v = self._sslobj.read(len, buffer)
|
|
else:
|
|
v = self._sslobj.read(len)
|
|
return v
|
|
|
|
def write(self, data):
|
|
"""Write 'data' to the SSL object and return the number of bytes
|
|
written.
|
|
|
|
The 'data' argument must support the buffer interface.
|
|
"""
|
|
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.
|
|
"""
|
|
return self._sslobj.getpeercert(binary_form)
|
|
|
|
def selected_npn_protocol(self):
|
|
"""Return the currently selected NPN protocol as a string, or ``None``
|
|
if a next protocol was not negotiated or if NPN is not supported by one
|
|
of the peers."""
|
|
if _ssl.HAS_NPN:
|
|
return self._sslobj.selected_npn_protocol()
|
|
|
|
def selected_alpn_protocol(self):
|
|
"""Return the currently selected ALPN protocol as a string, or ``None``
|
|
if a next protocol was not negotiated or if ALPN is not supported by one
|
|
of the peers."""
|
|
if _ssl.HAS_ALPN:
|
|
return self._sslobj.selected_alpn_protocol()
|
|
|
|
def cipher(self):
|
|
"""Return the currently selected cipher as a 3-tuple ``(name,
|
|
ssl_version, secret_bits)``."""
|
|
return self._sslobj.cipher()
|
|
|
|
def shared_ciphers(self):
|
|
"""Return a list of ciphers shared by the client during the handshake or
|
|
None if this is not a valid server connection.
|
|
"""
|
|
return self._sslobj.shared_ciphers()
|
|
|
|
def compression(self):
|
|
"""Return the current compression algorithm in use, or ``None`` if
|
|
compression was not negotiated or not supported by one of the peers."""
|
|
return self._sslobj.compression()
|
|
|
|
def pending(self):
|
|
"""Return the number of bytes that can be read immediately."""
|
|
return self._sslobj.pending()
|
|
|
|
def do_handshake(self):
|
|
"""Start the SSL/TLS handshake."""
|
|
self._sslobj.do_handshake()
|
|
|
|
def unwrap(self):
|
|
"""Start the SSL shutdown handshake."""
|
|
return self._sslobj.shutdown()
|
|
|
|
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)."""
|
|
return self._sslobj.get_channel_binding(cb_type)
|
|
|
|
def version(self):
|
|
"""Return a string identifying the protocol version used by the
|
|
current SSL channel. """
|
|
return self._sslobj.version()
|
|
|
|
def verify_client_post_handshake(self):
|
|
return self._sslobj.verify_client_post_handshake()
|
|
|
|
|
|
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, *args, **kwargs):
|
|
raise TypeError(
|
|
f"{self.__class__.__name__} does not have a public "
|
|
f"constructor. Instances are returned by "
|
|
f"SSLContext.wrap_socket()."
|
|
)
|
|
|
|
@classmethod
|
|
def _create(cls, sock, server_side=False, do_handshake_on_connect=True,
|
|
suppress_ragged_eofs=True, server_hostname=None,
|
|
context=None, session=None):
|
|
if sock.getsockopt(SOL_SOCKET, SO_TYPE) != SOCK_STREAM:
|
|
raise NotImplementedError("only stream sockets are supported")
|
|
if server_side:
|
|
if server_hostname:
|
|
raise ValueError("server_hostname can only be specified "
|
|
"in client mode")
|
|
if session is not None:
|
|
raise ValueError("session can only be specified in "
|
|
"client mode")
|
|
if context.check_hostname and not server_hostname:
|
|
raise ValueError("check_hostname requires server_hostname")
|
|
|
|
kwargs = dict(
|
|
family=sock.family, type=sock.type, proto=sock.proto,
|
|
fileno=sock.fileno()
|
|
)
|
|
self = cls.__new__(cls, **kwargs)
|
|
super(SSLSocket, self).__init__(**kwargs)
|
|
self.settimeout(sock.gettimeout())
|
|
sock.detach()
|
|
|
|
self._context = context
|
|
self._session = session
|
|
self._closed = False
|
|
self._sslobj = None
|
|
self.server_side = server_side
|
|
self.server_hostname = context._encode_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 OSError as e:
|
|
if e.errno != errno.ENOTCONN:
|
|
raise
|
|
connected = False
|
|
else:
|
|
connected = True
|
|
|
|
self._connected = connected
|
|
if connected:
|
|
# create the SSL object
|
|
try:
|
|
self._sslobj = self._context._wrap_socket(
|
|
self, server_side, self.server_hostname,
|
|
owner=self, session=self._session,
|
|
)
|
|
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
|
|
return self
|
|
|
|
@property
|
|
def context(self):
|
|
return self._context
|
|
|
|
@context.setter
|
|
def context(self, ctx):
|
|
self._context = ctx
|
|
self._sslobj.context = ctx
|
|
|
|
@property
|
|
def session(self):
|
|
"""The SSLSession for client socket."""
|
|
if self._sslobj is not None:
|
|
return self._sslobj.session
|
|
|
|
@session.setter
|
|
def session(self, session):
|
|
self._session = session
|
|
if self._sslobj is not None:
|
|
self._sslobj.session = session
|
|
|
|
@property
|
|
def session_reused(self):
|
|
"""Was the client session reused during handshake"""
|
|
if self._sslobj is not None:
|
|
return self._sslobj.session_reused
|
|
|
|
def dup(self):
|
|
raise NotImplementedError("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 self._sslobj is None:
|
|
raise ValueError("Read on closed or unwrapped SSL socket.")
|
|
try:
|
|
if buffer is not None:
|
|
return self._sslobj.read(len, buffer)
|
|
else:
|
|
return self._sslobj.read(len)
|
|
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 self._sslobj is None:
|
|
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.getpeercert(binary_form)
|
|
|
|
def selected_npn_protocol(self):
|
|
self._checkClosed()
|
|
if self._sslobj is None or not _ssl.HAS_NPN:
|
|
return None
|
|
else:
|
|
return self._sslobj.selected_npn_protocol()
|
|
|
|
def selected_alpn_protocol(self):
|
|
self._checkClosed()
|
|
if self._sslobj is None or not _ssl.HAS_ALPN:
|
|
return None
|
|
else:
|
|
return self._sslobj.selected_alpn_protocol()
|
|
|
|
def cipher(self):
|
|
self._checkClosed()
|
|
if self._sslobj is None:
|
|
return None
|
|
else:
|
|
return self._sslobj.cipher()
|
|
|
|
def shared_ciphers(self):
|
|
self._checkClosed()
|
|
if self._sslobj is None:
|
|
return None
|
|
else:
|
|
return self._sslobj.shared_ciphers()
|
|
|
|
def compression(self):
|
|
self._checkClosed()
|
|
if self._sslobj is None:
|
|
return None
|
|
else:
|
|
return self._sslobj.compression()
|
|
|
|
def send(self, data, flags=0):
|
|
self._checkClosed()
|
|
if self._sslobj is not None:
|
|
if flags != 0:
|
|
raise ValueError(
|
|
"non-zero flags not allowed in calls to send() on %s" %
|
|
self.__class__)
|
|
return self._sslobj.write(data)
|
|
else:
|
|
return super().send(data, flags)
|
|
|
|
def sendto(self, data, flags_or_addr, addr=None):
|
|
self._checkClosed()
|
|
if self._sslobj is not None:
|
|
raise ValueError("sendto not allowed on instances of %s" %
|
|
self.__class__)
|
|
elif addr is None:
|
|
return super().sendto(data, flags_or_addr)
|
|
else:
|
|
return super().sendto(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 is not None:
|
|
if flags != 0:
|
|
raise ValueError(
|
|
"non-zero flags not allowed in calls to sendall() on %s" %
|
|
self.__class__)
|
|
count = 0
|
|
with memoryview(data) as view, view.cast("B") as byte_view:
|
|
amount = len(byte_view)
|
|
while count < amount:
|
|
v = self.send(byte_view[count:])
|
|
count += v
|
|
else:
|
|
return super().sendall(data, flags)
|
|
|
|
def sendfile(self, file, offset=0, count=None):
|
|
"""Send a file, possibly by using os.sendfile() if this is a
|
|
clear-text socket. Return the total number of bytes sent.
|
|
"""
|
|
if self._sslobj is not None:
|
|
return self._sendfile_use_send(file, offset, count)
|
|
else:
|
|
# os.sendfile() works with plain sockets only
|
|
return super().sendfile(file, offset, count)
|
|
|
|
def recv(self, buflen=1024, flags=0):
|
|
self._checkClosed()
|
|
if self._sslobj is not None:
|
|
if flags != 0:
|
|
raise ValueError(
|
|
"non-zero flags not allowed in calls to recv() on %s" %
|
|
self.__class__)
|
|
return self.read(buflen)
|
|
else:
|
|
return super().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 is not None:
|
|
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 super().recv_into(buffer, nbytes, flags)
|
|
|
|
def recvfrom(self, buflen=1024, flags=0):
|
|
self._checkClosed()
|
|
if self._sslobj is not None:
|
|
raise ValueError("recvfrom not allowed on instances of %s" %
|
|
self.__class__)
|
|
else:
|
|
return super().recvfrom(buflen, flags)
|
|
|
|
def recvfrom_into(self, buffer, nbytes=None, flags=0):
|
|
self._checkClosed()
|
|
if self._sslobj is not None:
|
|
raise ValueError("recvfrom_into not allowed on instances of %s" %
|
|
self.__class__)
|
|
else:
|
|
return super().recvfrom_into(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 is not None:
|
|
return self._sslobj.pending()
|
|
else:
|
|
return 0
|
|
|
|
def shutdown(self, how):
|
|
self._checkClosed()
|
|
self._sslobj = None
|
|
super().shutdown(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 verify_client_post_handshake(self):
|
|
if self._sslobj:
|
|
return self._sslobj.verify_client_post_handshake()
|
|
else:
|
|
raise ValueError("No SSL wrapper around " + str(self))
|
|
|
|
def _real_close(self):
|
|
self._sslobj = None
|
|
super()._real_close()
|
|
|
|
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)
|
|
|
|
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 or self._sslobj is not None:
|
|
raise ValueError("attempt to connect already-connected SSLSocket!")
|
|
self._sslobj = self.context._wrap_socket(
|
|
self, False, self.server_hostname,
|
|
owner=self, session=self._session
|
|
)
|
|
try:
|
|
if connect_ex:
|
|
rc = super().connect_ex(addr)
|
|
else:
|
|
rc = None
|
|
super().connect(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 = super().accept()
|
|
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 self._sslobj is not None:
|
|
return self._sslobj.get_channel_binding(cb_type)
|
|
else:
|
|
if cb_type not in CHANNEL_BINDING_TYPES:
|
|
raise ValueError(
|
|
"{0} channel binding type not implemented".format(cb_type)
|
|
)
|
|
return None
|
|
|
|
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 not None:
|
|
return self._sslobj.version()
|
|
else:
|
|
return None
|
|
|
|
|
|
# Python does not support forward declaration of types.
|
|
SSLContext.sslsocket_class = SSLSocket
|
|
SSLContext.sslobject_class = SSLObject
|
|
|
|
|
|
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):
|
|
|
|
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")
|
|
context = SSLContext(ssl_version)
|
|
context.verify_mode = cert_reqs
|
|
if ca_certs:
|
|
context.load_verify_locations(ca_certs)
|
|
if certfile:
|
|
context.load_cert_chain(certfile, keyfile)
|
|
if ciphers:
|
|
context.set_ciphers(ciphers)
|
|
return context.wrap_socket(
|
|
sock=sock, server_side=server_side,
|
|
do_handshake_on_connect=do_handshake_on_connect,
|
|
suppress_ragged_eofs=suppress_ragged_eofs
|
|
)
|
|
|
|
# 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 = str(base64.standard_b64encode(der_cert_bytes), 'ASCII', 'strict')
|
|
ss = [PEM_HEADER]
|
|
ss += [f[i:i+64] for i in range(0, len(f), 64)]
|
|
ss.append(PEM_FOOTER + '\n')
|
|
return '\n'.join(ss)
|
|
|
|
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_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 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>')
|