| # Wrapper module for _ssl, providing some additional facilities |
| # implemented in Python. Written by Bill Janssen. |
| |
| """This module provides some more Pythonic support for SSL. |
| |
| Object types: |
| |
| SSLSocket -- subtype of socket.socket which does SSL over the socket |
| |
| Exceptions: |
| |
| SSLError -- exception raised for I/O errors |
| |
| Functions: |
| |
| cert_time_to_seconds -- convert time string used for certificate |
| notBefore and notAfter functions to integer |
| seconds past the Epoch (the time values |
| returned from time.time()) |
| |
| fetch_server_certificate (HOST, PORT) -- fetch the certificate provided |
| by the server running on HOST at port PORT. No |
| validation of the certificate is performed. |
| |
| Integer constants: |
| |
| SSL_ERROR_ZERO_RETURN |
| SSL_ERROR_WANT_READ |
| SSL_ERROR_WANT_WRITE |
| SSL_ERROR_WANT_X509_LOOKUP |
| SSL_ERROR_SYSCALL |
| SSL_ERROR_SSL |
| SSL_ERROR_WANT_CONNECT |
| |
| SSL_ERROR_EOF |
| SSL_ERROR_INVALID_ERROR_CODE |
| |
| The following group define certificate requirements that one side is |
| allowing/requiring from the other side: |
| |
| CERT_NONE - no certificates from the other side are required (or will |
| be looked at if provided) |
| CERT_OPTIONAL - certificates are not required, but if provided will be |
| validated, and if validation fails, the connection will |
| also fail |
| CERT_REQUIRED - certificates are required, and will be validated, and |
| if validation fails, the connection will also fail |
| |
| The following constants identify various SSL protocol variants: |
| |
| PROTOCOL_SSLv2 |
| PROTOCOL_SSLv3 |
| PROTOCOL_SSLv23 |
| PROTOCOL_TLS |
| PROTOCOL_TLS_CLIENT |
| PROTOCOL_TLS_SERVER |
| PROTOCOL_TLSv1 |
| PROTOCOL_TLSv1_1 |
| PROTOCOL_TLSv1_2 |
| |
| The following constants identify various SSL alert message descriptions as per |
| http://www.iana.org/assignments/tls-parameters/tls-parameters.xml#tls-parameters-6 |
| |
| ALERT_DESCRIPTION_CLOSE_NOTIFY |
| ALERT_DESCRIPTION_UNEXPECTED_MESSAGE |
| ALERT_DESCRIPTION_BAD_RECORD_MAC |
| ALERT_DESCRIPTION_RECORD_OVERFLOW |
| ALERT_DESCRIPTION_DECOMPRESSION_FAILURE |
| ALERT_DESCRIPTION_HANDSHAKE_FAILURE |
| ALERT_DESCRIPTION_BAD_CERTIFICATE |
| ALERT_DESCRIPTION_UNSUPPORTED_CERTIFICATE |
| ALERT_DESCRIPTION_CERTIFICATE_REVOKED |
| ALERT_DESCRIPTION_CERTIFICATE_EXPIRED |
| ALERT_DESCRIPTION_CERTIFICATE_UNKNOWN |
| ALERT_DESCRIPTION_ILLEGAL_PARAMETER |
| ALERT_DESCRIPTION_UNKNOWN_CA |
| ALERT_DESCRIPTION_ACCESS_DENIED |
| ALERT_DESCRIPTION_DECODE_ERROR |
| ALERT_DESCRIPTION_DECRYPT_ERROR |
| ALERT_DESCRIPTION_PROTOCOL_VERSION |
| ALERT_DESCRIPTION_INSUFFICIENT_SECURITY |
| ALERT_DESCRIPTION_INTERNAL_ERROR |
| ALERT_DESCRIPTION_USER_CANCELLED |
| ALERT_DESCRIPTION_NO_RENEGOTIATION |
| ALERT_DESCRIPTION_UNSUPPORTED_EXTENSION |
| ALERT_DESCRIPTION_CERTIFICATE_UNOBTAINABLE |
| ALERT_DESCRIPTION_UNRECOGNIZED_NAME |
| ALERT_DESCRIPTION_BAD_CERTIFICATE_STATUS_RESPONSE |
| ALERT_DESCRIPTION_BAD_CERTIFICATE_HASH_VALUE |
| ALERT_DESCRIPTION_UNKNOWN_PSK_IDENTITY |
| """ |
| |
| import sys |
| import os |
| from collections import namedtuple |
| from enum import Enum as _Enum, IntEnum as _IntEnum, IntFlag as _IntFlag |
| |
| import _ssl # if we can't import it, let the error propagate |
| |
| from _ssl import OPENSSL_VERSION_NUMBER, OPENSSL_VERSION_INFO, OPENSSL_VERSION |
| from _ssl import _SSLContext, MemoryBIO, SSLSession |
| from _ssl import ( |
| SSLError, SSLZeroReturnError, SSLWantReadError, SSLWantWriteError, |
| SSLSyscallError, SSLEOFError, SSLCertVerificationError |
| ) |
| from _ssl import txt2obj as _txt2obj, nid2obj as _nid2obj |
| from _ssl import RAND_status, RAND_add, RAND_bytes, RAND_pseudo_bytes |
| try: |
| from _ssl import RAND_egd |
| except ImportError: |
| # LibreSSL does not provide RAND_egd |
| pass |
| |
| |
| from _ssl import ( |
| HAS_SNI, HAS_ECDH, HAS_NPN, HAS_ALPN, HAS_SSLv2, HAS_SSLv3, HAS_TLSv1, |
| HAS_TLSv1_1, HAS_TLSv1_2, HAS_TLSv1_3 |
| ) |
| from _ssl import _DEFAULT_CIPHERS, _OPENSSL_API_VERSION |
| |
| |
| _IntEnum._convert( |
| '_SSLMethod', __name__, |
| lambda name: name.startswith('PROTOCOL_') and name != 'PROTOCOL_SSLv23', |
| source=_ssl) |
| |
| _IntFlag._convert( |
| 'Options', __name__, |
| lambda name: name.startswith('OP_'), |
| source=_ssl) |
| |
| _IntEnum._convert( |
| 'AlertDescription', __name__, |
| lambda name: name.startswith('ALERT_DESCRIPTION_'), |
| source=_ssl) |
| |
| _IntEnum._convert( |
| 'SSLErrorNumber', __name__, |
| lambda name: name.startswith('SSL_ERROR_'), |
| source=_ssl) |
| |
| _IntFlag._convert( |
| 'VerifyFlags', __name__, |
| lambda name: name.startswith('VERIFY_'), |
| source=_ssl) |
| |
| _IntEnum._convert( |
| 'VerifyMode', __name__, |
| lambda name: name.startswith('CERT_'), |
| source=_ssl) |
| |
| PROTOCOL_SSLv23 = _SSLMethod.PROTOCOL_SSLv23 = _SSLMethod.PROTOCOL_TLS |
| _PROTOCOL_NAMES = {value: name for name, value in _SSLMethod.__members__.items()} |
| |
| _SSLv2_IF_EXISTS = getattr(_SSLMethod, 'PROTOCOL_SSLv2', None) |
| |
| |
| class TLSVersion(_IntEnum): |
| MINIMUM_SUPPORTED = _ssl.PROTO_MINIMUM_SUPPORTED |
| SSLv3 = _ssl.PROTO_SSLv3 |
| TLSv1 = _ssl.PROTO_TLSv1 |
| TLSv1_1 = _ssl.PROTO_TLSv1_1 |
| TLSv1_2 = _ssl.PROTO_TLSv1_2 |
| TLSv1_3 = _ssl.PROTO_TLSv1_3 |
| MAXIMUM_SUPPORTED = _ssl.PROTO_MAXIMUM_SUPPORTED |
| |
| |
| if sys.platform == "win32": |
| from _ssl import enum_certificates, enum_crls |
| |
| from socket import socket, AF_INET, SOCK_STREAM, create_connection |
| from socket import SOL_SOCKET, SO_TYPE |
| import socket as _socket |
| import base64 # for DER-to-PEM translation |
| import errno |
| import warnings |
| |
| |
| socket_error = OSError # keep that public name in module namespace |
| |
| CHANNEL_BINDING_TYPES = ['tls-unique'] |
| |
| HAS_NEVER_CHECK_COMMON_NAME = hasattr(_ssl, 'HOSTFLAG_NEVER_CHECK_SUBJECT') |
| |
| |
| _RESTRICTED_SERVER_CIPHERS = _DEFAULT_CIPHERS |
| |
| CertificateError = SSLCertVerificationError |
| |
| |
| def _dnsname_match(dn, hostname): |
| """Matching according to RFC 6125, section 6.4.3 |
| |
| - Hostnames are compared lower case. |
| - For IDNA, both dn and hostname must be encoded as IDN A-label (ACE). |
| - Partial wildcards like 'www*.example.org', multiple wildcards, sole |
| wildcard or wildcards in labels other then the left-most label are not |
| supported and a CertificateError is raised. |
| - A wildcard must match at least one character. |
| """ |
| if not dn: |
| return False |
| |
| wildcards = dn.count('*') |
| # speed up common case w/o wildcards |
| if not wildcards: |
| return dn.lower() == hostname.lower() |
| |
| if wildcards > 1: |
| raise CertificateError( |
| "too many wildcards in certificate DNS name: {!r}.".format(dn)) |
| |
| dn_leftmost, sep, dn_remainder = dn.partition('.') |
| |
| if '*' in dn_remainder: |
| # Only match wildcard in leftmost segment. |
| raise CertificateError( |
| "wildcard can only be present in the leftmost label: " |
| "{!r}.".format(dn)) |
| |
| if not sep: |
| # no right side |
| raise CertificateError( |
| "sole wildcard without additional labels are not support: " |
| "{!r}.".format(dn)) |
| |
| if dn_leftmost != '*': |
| # no partial wildcard matching |
| raise CertificateError( |
| "partial wildcards in leftmost label are not supported: " |
| "{!r}.".format(dn)) |
| |
| hostname_leftmost, sep, hostname_remainder = hostname.partition('.') |
| if not hostname_leftmost or not sep: |
| # wildcard must match at least one char |
| return False |
| return dn_remainder.lower() == hostname_remainder.lower() |
| |
| |
| def _inet_paton(ipname): |
| """Try to convert an IP address to packed binary form |
| |
| Supports IPv4 addresses on all platforms and IPv6 on platforms with IPv6 |
| support. |
| """ |
| # inet_aton() also accepts strings like '1' |
| if ipname.count('.') == 3: |
| try: |
| return _socket.inet_aton(ipname) |
| except OSError: |
| pass |
| |
| try: |
| return _socket.inet_pton(_socket.AF_INET6, ipname) |
| except OSError: |
| raise ValueError("{!r} is neither an IPv4 nor an IP6 " |
| "address.".format(ipname)) |
| except AttributeError: |
| # AF_INET6 not available |
| pass |
| |
| raise ValueError("{!r} is not an IPv4 address.".format(ipname)) |
| |
| |
| def _ipaddress_match(ipname, host_ip): |
| """Exact matching of IP addresses. |
| |
| RFC 6125 explicitly doesn't define an algorithm for this |
| (section 1.7.2 - "Out of Scope"). |
| """ |
| # OpenSSL may add a trailing newline to a subjectAltName's IP address |
| ip = _inet_paton(ipname.rstrip()) |
| return ip == host_ip |
| |
| |
| def match_hostname(cert, hostname): |
| """Verify that *cert* (in decoded format as returned by |
| SSLSocket.getpeercert()) matches the *hostname*. RFC 2818 and RFC 6125 |
| rules are followed. |
| |
| The function matches IP addresses rather than dNSNames if hostname is a |
| valid ipaddress string. IPv4 addresses are supported on all platforms. |
| IPv6 addresses are supported on platforms with IPv6 support (AF_INET6 |
| and inet_pton). |
| |
| CertificateError is raised on failure. On success, the function |
| returns nothing. |
| """ |
| if not cert: |
| raise ValueError("empty or no certificate, match_hostname needs a " |
| "SSL socket or SSL context with either " |
| "CERT_OPTIONAL or CERT_REQUIRED") |
| try: |
| host_ip = _inet_paton(hostname) |
| except ValueError: |
| # Not an IP address (common case) |
| host_ip = None |
| dnsnames = [] |
| san = cert.get('subjectAltName', ()) |
| for key, value in san: |
| if key == 'DNS': |
| if host_ip is None and _dnsname_match(value, hostname): |
| return |
| dnsnames.append(value) |
| elif key == 'IP Address': |
| if host_ip is not None and _ipaddress_match(value, host_ip): |
| return |
| dnsnames.append(value) |
| if not dnsnames: |
| # The subject is only checked when there is no dNSName entry |
| # in subjectAltName |
| for sub in cert.get('subject', ()): |
| for key, value in sub: |
| # XXX according to RFC 2818, the most specific Common Name |
| # must be used. |
| if key == 'commonName': |
| if _dnsname_match(value, hostname): |
| return |
| dnsnames.append(value) |
| if len(dnsnames) > 1: |
| raise CertificateError("hostname %r " |
| "doesn't match either of %s" |
| % (hostname, ', '.join(map(repr, dnsnames)))) |
| elif len(dnsnames) == 1: |
| raise CertificateError("hostname %r " |
| "doesn't match %r" |
| % (hostname, dnsnames[0])) |
| else: |
| raise CertificateError("no appropriate commonName or " |
| "subjectAltName fields were found") |
| |
| |
| DefaultVerifyPaths = namedtuple("DefaultVerifyPaths", |
| "cafile capath openssl_cafile_env openssl_cafile openssl_capath_env " |
| "openssl_capath") |
| |
| def get_default_verify_paths(): |
| """Return paths to default cafile and capath. |
| """ |
| parts = _ssl.get_default_verify_paths() |
| |
| # environment vars shadow paths |
| cafile = os.environ.get(parts[0], parts[1]) |
| capath = os.environ.get(parts[2], parts[3]) |
| |
| return DefaultVerifyPaths(cafile if os.path.isfile(cafile) else None, |
| capath if os.path.isdir(capath) else None, |
| *parts) |
| |
| |
| class _ASN1Object(namedtuple("_ASN1Object", "nid shortname longname oid")): |
| """ASN.1 object identifier lookup |
| """ |
| __slots__ = () |
| |
| def __new__(cls, oid): |
| return super().__new__(cls, *_txt2obj(oid, name=False)) |
| |
| @classmethod |
| def fromnid(cls, nid): |
| """Create _ASN1Object from OpenSSL numeric ID |
| """ |
| return super().__new__(cls, *_nid2obj(nid)) |
| |
| @classmethod |
| def fromname(cls, name): |
| """Create _ASN1Object from short name, long name or OID |
| """ |
| return super().__new__(cls, *_txt2obj(name, name=True)) |
| |
| |
| class Purpose(_ASN1Object, _Enum): |
| """SSLContext purpose flags with X509v3 Extended Key Usage objects |
| """ |
| SERVER_AUTH = '1.3.6.1.5.5.7.3.1' |
| CLIENT_AUTH = '1.3.6.1.5.5.7.3.2' |
| |
| |
| class SSLContext(_SSLContext): |
| """An SSLContext holds various SSL-related configuration options and |
| data, such as certificates and possibly a private key.""" |
| _windows_cert_stores = ("CA", "ROOT") |
| |
| sslsocket_class = None # SSLSocket is assigned later. |
| sslobject_class = None # SSLObject is assigned later. |
| |
| def __new__(cls, protocol=PROTOCOL_TLS, *args, **kwargs): |
| self = _SSLContext.__new__(cls, protocol) |
| return self |
| |
| def _encode_hostname(self, hostname): |
| if hostname is None: |
| return None |
| elif isinstance(hostname, str): |
| return hostname.encode('idna').decode('ascii') |
| else: |
| return hostname.decode('ascii') |
| |
| def wrap_socket(self, sock, server_side=False, |
| do_handshake_on_connect=True, |
| suppress_ragged_eofs=True, |
| server_hostname=None, session=None): |
| # SSLSocket class handles server_hostname encoding before it calls |
| # ctx._wrap_socket() |
| return self.sslsocket_class._create( |
| 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, |
| session=session |
| ) |
| |
| def wrap_bio(self, incoming, outgoing, server_side=False, |
| server_hostname=None, session=None): |
| # Need to encode server_hostname here because _wrap_bio() can only |
| # handle ASCII str. |
| return self.sslobject_class._create( |
| incoming, outgoing, server_side=server_side, |
| server_hostname=self._encode_hostname(server_hostname), |
| session=session, 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 set_servername_callback(self, server_name_callback): |
| if server_name_callback is None: |
| self.sni_callback = None |
| else: |
| if not callable(server_name_callback): |
| raise TypeError("not a callable object") |
| |
| def shim_cb(sslobj, servername, sslctx): |
| servername = self._encode_hostname(servername) |
| return server_name_callback(sslobj, servername, sslctx) |
| |
| self.sni_callback = shim_cb |
| |
| def set_alpn_protocols(self, alpn_protocols): |
| protos = bytearray() |
| for protocol in alpn_protocols: |
| b = bytes(protocol, 'ascii') |
| if len(b) == 0 or len(b) > 255: |
| raise SSLError('ALPN protocols must be 1 to 255 in length') |
| protos.append(len(b)) |
| protos.extend(b) |
| |
| self._set_alpn_protocols(protos) |
| |
| def _load_windows_store_certs(self, storename, purpose): |
| certs = bytearray() |
| try: |
| for cert, encoding, trust in enum_certificates(storename): |
| # CA certs are never PKCS#7 encoded |
| if encoding == "x509_asn": |
| if trust is True or purpose.oid in trust: |
| certs.extend(cert) |
| except PermissionError: |
| warnings.warn("unable to enumerate Windows certificate store") |
| if certs: |
| self.load_verify_locations(cadata=certs) |
| return certs |
| |
| def load_default_certs(self, purpose=Purpose.SERVER_AUTH): |
| if not isinstance(purpose, _ASN1Object): |
| raise TypeError(purpose) |
| if sys.platform == "win32": |
| for storename in self._windows_cert_stores: |
| self._load_windows_store_certs(storename, purpose) |
| self.set_default_verify_paths() |
| |
| if hasattr(_SSLContext, 'minimum_version'): |
| @property |
| def minimum_version(self): |
| return TLSVersion(super().minimum_version) |
| |
| @minimum_version.setter |
| def minimum_version(self, value): |
| if value == TLSVersion.SSLv3: |
| self.options &= ~Options.OP_NO_SSLv3 |
| super(SSLContext, SSLContext).minimum_version.__set__(self, value) |
| |
| @property |
| def maximum_version(self): |
| return TLSVersion(super().maximum_version) |
| |
| @maximum_version.setter |
| def maximum_version(self, value): |
| super(SSLContext, SSLContext).maximum_version.__set__(self, value) |
| |
| @property |
| def options(self): |
| return Options(super().options) |
| |
| @options.setter |
| def options(self, value): |
| super(SSLContext, SSLContext).options.__set__(self, value) |
| |
| 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 incluging 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() |
| |
| |
| 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 NotImplemented("Can't dup() %s instances" % |
| self.__class__.__name__) |
| |
| def _checkClosed(self, msg=None): |
| # raise an exception here if you wish to check for spurious closes |
| pass |
| |
| def _check_connected(self): |
| if not self._connected: |
| # getpeername() will raise ENOTCONN if the socket is really |
| # not connected; note that we can be connected even without |
| # _connected being set, e.g. if connect() first returned |
| # EAGAIN. |
| self.getpeername() |
| |
| def read(self, len=1024, buffer=None): |
| """Read up to LEN bytes and return them. |
| Return zero-length string on EOF.""" |
| |
| self._checkClosed() |
| if 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 _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>') |