--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/urllib3/util/ssl_.py	Sun May 05 23:32:17 2024 -0400
@@ -0,0 +1,509 @@
+from __future__ import annotations
+
+import hmac
+import os
+import socket
+import sys
+import typing
+import warnings
+from binascii import unhexlify
+from hashlib import md5, sha1, sha256
+
+from ..exceptions import ProxySchemeUnsupported, SSLError
+from .url import _BRACELESS_IPV6_ADDRZ_RE, _IPV4_RE
+
+SSLContext = None
+SSLTransport = None
+HAS_NEVER_CHECK_COMMON_NAME = False
+IS_PYOPENSSL = False
+ALPN_PROTOCOLS = ["http/1.1"]
+
+_TYPE_VERSION_INFO = typing.Tuple[int, int, int, str, int]
+
+# Maps the length of a digest to a possible hash function producing this digest
+HASHFUNC_MAP = {32: md5, 40: sha1, 64: sha256}
+
+
+def _is_bpo_43522_fixed(
+    implementation_name: str,
+    version_info: _TYPE_VERSION_INFO,
+    pypy_version_info: _TYPE_VERSION_INFO | None,
+) -> bool:
+    """Return True for CPython 3.8.9+, 3.9.3+ or 3.10+ and PyPy 7.3.8+ where
+    setting SSLContext.hostname_checks_common_name to False works.
+
+    Outside of CPython and PyPy we don't know which implementations work
+    or not so we conservatively use our hostname matching as we know that works
+    on all implementations.
+
+    https://github.com/urllib3/urllib3/issues/2192#issuecomment-821832963
+    https://foss.heptapod.net/pypy/pypy/-/issues/3539
+    """
+    if implementation_name == "pypy":
+        # https://foss.heptapod.net/pypy/pypy/-/issues/3129
+        return pypy_version_info >= (7, 3, 8)  # type: ignore[operator]
+    elif implementation_name == "cpython":
+        major_minor = version_info[:2]
+        micro = version_info[2]
+        return (
+            (major_minor == (3, 8) and micro >= 9)
+            or (major_minor == (3, 9) and micro >= 3)
+            or major_minor >= (3, 10)
+        )
+    else:  # Defensive:
+        return False
+
+
+def _is_has_never_check_common_name_reliable(
+    openssl_version: str,
+    openssl_version_number: int,
+    implementation_name: str,
+    version_info: _TYPE_VERSION_INFO,
+    pypy_version_info: _TYPE_VERSION_INFO | None,
+) -> bool:
+    # As of May 2023, all released versions of LibreSSL fail to reject certificates with
+    # only common names, see https://github.com/urllib3/urllib3/pull/3024
+    is_openssl = openssl_version.startswith("OpenSSL ")
+    # Before fixing OpenSSL issue #14579, the SSL_new() API was not copying hostflags
+    # like X509_CHECK_FLAG_NEVER_CHECK_SUBJECT, which tripped up CPython.
+    # https://github.com/openssl/openssl/issues/14579
+    # This was released in OpenSSL 1.1.1l+ (>=0x101010cf)
+    is_openssl_issue_14579_fixed = openssl_version_number >= 0x101010CF
+
+    return is_openssl and (
+        is_openssl_issue_14579_fixed
+        or _is_bpo_43522_fixed(implementation_name, version_info, pypy_version_info)
+    )
+
+
+if typing.TYPE_CHECKING:
+    from ssl import VerifyMode
+    from typing import Literal, TypedDict
+
+    from .ssltransport import SSLTransport as SSLTransportType
+
+    class _TYPE_PEER_CERT_RET_DICT(TypedDict, total=False):
+        subjectAltName: tuple[tuple[str, str], ...]
+        subject: tuple[tuple[tuple[str, str], ...], ...]
+        serialNumber: str
+
+
+# Mapping from 'ssl.PROTOCOL_TLSX' to 'TLSVersion.X'
+_SSL_VERSION_TO_TLS_VERSION: dict[int, int] = {}
+
+try:  # Do we have ssl at all?
+    import ssl
+    from ssl import (  # type: ignore[assignment]
+        CERT_REQUIRED,
+        HAS_NEVER_CHECK_COMMON_NAME,
+        OP_NO_COMPRESSION,
+        OP_NO_TICKET,
+        OPENSSL_VERSION,
+        OPENSSL_VERSION_NUMBER,
+        PROTOCOL_TLS,
+        PROTOCOL_TLS_CLIENT,
+        OP_NO_SSLv2,
+        OP_NO_SSLv3,
+        SSLContext,
+        TLSVersion,
+    )
+
+    PROTOCOL_SSLv23 = PROTOCOL_TLS
+
+    # Setting SSLContext.hostname_checks_common_name = False didn't work before CPython
+    # 3.8.9, 3.9.3, and 3.10 (but OK on PyPy) or OpenSSL 1.1.1l+
+    if HAS_NEVER_CHECK_COMMON_NAME and not _is_has_never_check_common_name_reliable(
+        OPENSSL_VERSION,
+        OPENSSL_VERSION_NUMBER,
+        sys.implementation.name,
+        sys.version_info,
+        sys.pypy_version_info if sys.implementation.name == "pypy" else None,  # type: ignore[attr-defined]
+    ):
+        HAS_NEVER_CHECK_COMMON_NAME = False
+
+    # Need to be careful here in case old TLS versions get
+    # removed in future 'ssl' module implementations.
+    for attr in ("TLSv1", "TLSv1_1", "TLSv1_2"):
+        try:
+            _SSL_VERSION_TO_TLS_VERSION[getattr(ssl, f"PROTOCOL_{attr}")] = getattr(
+                TLSVersion, attr
+            )
+        except AttributeError:  # Defensive:
+            continue
+
+    from .ssltransport import SSLTransport  # type: ignore[assignment]
+except ImportError:
+    OP_NO_COMPRESSION = 0x20000  # type: ignore[assignment]
+    OP_NO_TICKET = 0x4000  # type: ignore[assignment]
+    OP_NO_SSLv2 = 0x1000000  # type: ignore[assignment]
+    OP_NO_SSLv3 = 0x2000000  # type: ignore[assignment]
+    PROTOCOL_SSLv23 = PROTOCOL_TLS = 2  # type: ignore[assignment]
+    PROTOCOL_TLS_CLIENT = 16  # type: ignore[assignment]
+
+
+_TYPE_PEER_CERT_RET = typing.Union["_TYPE_PEER_CERT_RET_DICT", bytes, None]
+
+
+def assert_fingerprint(cert: bytes | None, fingerprint: str) -> None:
+    """
+    Checks if given fingerprint matches the supplied certificate.
+
+    :param cert:
+        Certificate as bytes object.
+    :param fingerprint:
+        Fingerprint as string of hexdigits, can be interspersed by colons.
+    """
+
+    if cert is None:
+        raise SSLError("No certificate for the peer.")
+
+    fingerprint = fingerprint.replace(":", "").lower()
+    digest_length = len(fingerprint)
+    hashfunc = HASHFUNC_MAP.get(digest_length)
+    if not hashfunc:
+        raise SSLError(f"Fingerprint of invalid length: {fingerprint}")
+
+    # We need encode() here for py32; works on py2 and p33.
+    fingerprint_bytes = unhexlify(fingerprint.encode())
+
+    cert_digest = hashfunc(cert).digest()
+
+    if not hmac.compare_digest(cert_digest, fingerprint_bytes):
+        raise SSLError(
+            f'Fingerprints did not match. Expected "{fingerprint}", got "{cert_digest.hex()}"'
+        )
+
+
+def resolve_cert_reqs(candidate: None | int | str) -> VerifyMode:
+    """
+    Resolves the argument to a numeric constant, which can be passed to
+    the wrap_socket function/method from the ssl module.
+    Defaults to :data:`ssl.CERT_REQUIRED`.
+    If given a string it is assumed to be the name of the constant in the
+    :mod:`ssl` module or its abbreviation.
+    (So you can specify `REQUIRED` instead of `CERT_REQUIRED`.
+    If it's neither `None` nor a string we assume it is already the numeric
+    constant which can directly be passed to wrap_socket.
+    """
+    if candidate is None:
+        return CERT_REQUIRED
+
+    if isinstance(candidate, str):
+        res = getattr(ssl, candidate, None)
+        if res is None:
+            res = getattr(ssl, "CERT_" + candidate)
+        return res  # type: ignore[no-any-return]
+
+    return candidate  # type: ignore[return-value]
+
+
+def resolve_ssl_version(candidate: None | int | str) -> int:
+    """
+    like resolve_cert_reqs
+    """
+    if candidate is None:
+        return PROTOCOL_TLS
+
+    if isinstance(candidate, str):
+        res = getattr(ssl, candidate, None)
+        if res is None:
+            res = getattr(ssl, "PROTOCOL_" + candidate)
+        return typing.cast(int, res)
+
+    return candidate
+
+
+def create_urllib3_context(
+    ssl_version: int | None = None,
+    cert_reqs: int | None = None,
+    options: int | None = None,
+    ciphers: str | None = None,
+    ssl_minimum_version: int | None = None,
+    ssl_maximum_version: int | None = None,
+) -> ssl.SSLContext:
+    """Creates and configures an :class:`ssl.SSLContext` instance for use with urllib3.
+
+    :param ssl_version:
+        The desired protocol version to use. This will default to
+        PROTOCOL_SSLv23 which will negotiate the highest protocol that both
+        the server and your installation of OpenSSL support.
+
+        This parameter is deprecated instead use 'ssl_minimum_version'.
+    :param ssl_minimum_version:
+        The minimum version of TLS to be used. Use the 'ssl.TLSVersion' enum for specifying the value.
+    :param ssl_maximum_version:
+        The maximum version of TLS to be used. Use the 'ssl.TLSVersion' enum for specifying the value.
+        Not recommended to set to anything other than 'ssl.TLSVersion.MAXIMUM_SUPPORTED' which is the
+        default value.
+    :param cert_reqs:
+        Whether to require the certificate verification. This defaults to
+        ``ssl.CERT_REQUIRED``.
+    :param options:
+        Specific OpenSSL options. These default to ``ssl.OP_NO_SSLv2``,
+        ``ssl.OP_NO_SSLv3``, ``ssl.OP_NO_COMPRESSION``, and ``ssl.OP_NO_TICKET``.
+    :param ciphers:
+        Which cipher suites to allow the server to select. Defaults to either system configured
+        ciphers if OpenSSL 1.1.1+, otherwise uses a secure default set of ciphers.
+    :returns:
+        Constructed SSLContext object with specified options
+    :rtype: SSLContext
+    """
+    if SSLContext is None:
+        raise TypeError("Can't create an SSLContext object without an ssl module")
+
+    # This means 'ssl_version' was specified as an exact value.
+    if ssl_version not in (None, PROTOCOL_TLS, PROTOCOL_TLS_CLIENT):
+        # Disallow setting 'ssl_version' and 'ssl_minimum|maximum_version'
+        # to avoid conflicts.
+        if ssl_minimum_version is not None or ssl_maximum_version is not None:
+            raise ValueError(
+                "Can't specify both 'ssl_version' and either "
+                "'ssl_minimum_version' or 'ssl_maximum_version'"
+            )
+
+        # 'ssl_version' is deprecated and will be removed in the future.
+        else:
+            # Use 'ssl_minimum_version' and 'ssl_maximum_version' instead.
+            ssl_minimum_version = _SSL_VERSION_TO_TLS_VERSION.get(
+                ssl_version, TLSVersion.MINIMUM_SUPPORTED
+            )
+            ssl_maximum_version = _SSL_VERSION_TO_TLS_VERSION.get(
+                ssl_version, TLSVersion.MAXIMUM_SUPPORTED
+            )
+
+            # This warning message is pushing users to use 'ssl_minimum_version'
+            # instead of both min/max. Best practice is to only set the minimum version and
+            # keep the maximum version to be it's default value: 'TLSVersion.MAXIMUM_SUPPORTED'
+            warnings.warn(
+                "'ssl_version' option is deprecated and will be "
+                "removed in urllib3 v2.1.0. Instead use 'ssl_minimum_version'",
+                category=DeprecationWarning,
+                stacklevel=2,
+            )
+
+    # PROTOCOL_TLS is deprecated in Python 3.10 so we always use PROTOCOL_TLS_CLIENT
+    context = SSLContext(PROTOCOL_TLS_CLIENT)
+
+    if ssl_minimum_version is not None:
+        context.minimum_version = ssl_minimum_version
+    else:  # Python <3.10 defaults to 'MINIMUM_SUPPORTED' so explicitly set TLSv1.2 here
+        context.minimum_version = TLSVersion.TLSv1_2
+
+    if ssl_maximum_version is not None:
+        context.maximum_version = ssl_maximum_version
+
+    # Unless we're given ciphers defer to either system ciphers in
+    # the case of OpenSSL 1.1.1+ or use our own secure default ciphers.
+    if ciphers:
+        context.set_ciphers(ciphers)
+
+    # Setting the default here, as we may have no ssl module on import
+    cert_reqs = ssl.CERT_REQUIRED if cert_reqs is None else cert_reqs
+
+    if options is None:
+        options = 0
+        # SSLv2 is easily broken and is considered harmful and dangerous
+        options |= OP_NO_SSLv2
+        # SSLv3 has several problems and is now dangerous
+        options |= OP_NO_SSLv3
+        # Disable compression to prevent CRIME attacks for OpenSSL 1.0+
+        # (issue #309)
+        options |= OP_NO_COMPRESSION
+        # TLSv1.2 only. Unless set explicitly, do not request tickets.
+        # This may save some bandwidth on wire, and although the ticket is encrypted,
+        # there is a risk associated with it being on wire,
+        # if the server is not rotating its ticketing keys properly.
+        options |= OP_NO_TICKET
+
+    context.options |= options
+
+    # Enable post-handshake authentication for TLS 1.3, see GH #1634. PHA is
+    # necessary for conditional client cert authentication with TLS 1.3.
+    # The attribute is None for OpenSSL <= 1.1.0 or does not exist when using
+    # an SSLContext created by pyOpenSSL.
+    if getattr(context, "post_handshake_auth", None) is not None:
+        context.post_handshake_auth = True
+
+    # The order of the below lines setting verify_mode and check_hostname
+    # matter due to safe-guards SSLContext has to prevent an SSLContext with
+    # check_hostname=True, verify_mode=NONE/OPTIONAL.
+    # We always set 'check_hostname=False' for pyOpenSSL so we rely on our own
+    # 'ssl.match_hostname()' implementation.
+    if cert_reqs == ssl.CERT_REQUIRED and not IS_PYOPENSSL:
+        context.verify_mode = cert_reqs
+        context.check_hostname = True
+    else:
+        context.check_hostname = False
+        context.verify_mode = cert_reqs
+
+    try:
+        context.hostname_checks_common_name = False
+    except AttributeError:  # Defensive: for CPython < 3.8.9 and 3.9.3; for PyPy < 7.3.8
+        pass
+
+    # Enable logging of TLS session keys via defacto standard environment variable
+    # 'SSLKEYLOGFILE', if the feature is available (Python 3.8+). Skip empty values.
+    if hasattr(context, "keylog_filename"):
+        sslkeylogfile = os.environ.get("SSLKEYLOGFILE")
+        if sslkeylogfile:
+            context.keylog_filename = sslkeylogfile
+
+    return context
+
+
+@typing.overload
+def ssl_wrap_socket(
+    sock: socket.socket,
+    keyfile: str | None = ...,
+    certfile: str | None = ...,
+    cert_reqs: int | None = ...,
+    ca_certs: str | None = ...,
+    server_hostname: str | None = ...,
+    ssl_version: int | None = ...,
+    ciphers: str | None = ...,
+    ssl_context: ssl.SSLContext | None = ...,
+    ca_cert_dir: str | None = ...,
+    key_password: str | None = ...,
+    ca_cert_data: None | str | bytes = ...,
+    tls_in_tls: Literal[False] = ...,
+) -> ssl.SSLSocket:
+    ...
+
+
+@typing.overload
+def ssl_wrap_socket(
+    sock: socket.socket,
+    keyfile: str | None = ...,
+    certfile: str | None = ...,
+    cert_reqs: int | None = ...,
+    ca_certs: str | None = ...,
+    server_hostname: str | None = ...,
+    ssl_version: int | None = ...,
+    ciphers: str | None = ...,
+    ssl_context: ssl.SSLContext | None = ...,
+    ca_cert_dir: str | None = ...,
+    key_password: str | None = ...,
+    ca_cert_data: None | str | bytes = ...,
+    tls_in_tls: bool = ...,
+) -> ssl.SSLSocket | SSLTransportType:
+    ...
+
+
+def ssl_wrap_socket(
+    sock: socket.socket,
+    keyfile: str | None = None,
+    certfile: str | None = None,
+    cert_reqs: int | None = None,
+    ca_certs: str | None = None,
+    server_hostname: str | None = None,
+    ssl_version: int | None = None,
+    ciphers: str | None = None,
+    ssl_context: ssl.SSLContext | None = None,
+    ca_cert_dir: str | None = None,
+    key_password: str | None = None,
+    ca_cert_data: None | str | bytes = None,
+    tls_in_tls: bool = False,
+) -> ssl.SSLSocket | SSLTransportType:
+    """
+    All arguments except for server_hostname, ssl_context, tls_in_tls, ca_cert_data and
+    ca_cert_dir have the same meaning as they do when using
+    :func:`ssl.create_default_context`, :meth:`ssl.SSLContext.load_cert_chain`,
+    :meth:`ssl.SSLContext.set_ciphers` and :meth:`ssl.SSLContext.wrap_socket`.
+
+    :param server_hostname:
+        When SNI is supported, the expected hostname of the certificate
+    :param ssl_context:
+        A pre-made :class:`SSLContext` object. If none is provided, one will
+        be created using :func:`create_urllib3_context`.
+    :param ciphers:
+        A string of ciphers we wish the client to support.
+    :param ca_cert_dir:
+        A directory containing CA certificates in multiple separate files, as
+        supported by OpenSSL's -CApath flag or the capath argument to
+        SSLContext.load_verify_locations().
+    :param key_password:
+        Optional password if the keyfile is encrypted.
+    :param ca_cert_data:
+        Optional string containing CA certificates in PEM format suitable for
+        passing as the cadata parameter to SSLContext.load_verify_locations()
+    :param tls_in_tls:
+        Use SSLTransport to wrap the existing socket.
+    """
+    context = ssl_context
+    if context is None:
+        # Note: This branch of code and all the variables in it are only used in tests.
+        # We should consider deprecating and removing this code.
+        context = create_urllib3_context(ssl_version, cert_reqs, ciphers=ciphers)
+
+    if ca_certs or ca_cert_dir or ca_cert_data:
+        try:
+            context.load_verify_locations(ca_certs, ca_cert_dir, ca_cert_data)
+        except OSError as e:
+            raise SSLError(e) from e
+
+    elif ssl_context is None and hasattr(context, "load_default_certs"):
+        # try to load OS default certs; works well on Windows.
+        context.load_default_certs()
+
+    # Attempt to detect if we get the goofy behavior of the
+    # keyfile being encrypted and OpenSSL asking for the
+    # passphrase via the terminal and instead error out.
+    if keyfile and key_password is None and _is_key_file_encrypted(keyfile):
+        raise SSLError("Client private key is encrypted, password is required")
+
+    if certfile:
+        if key_password is None:
+            context.load_cert_chain(certfile, keyfile)
+        else:
+            context.load_cert_chain(certfile, keyfile, key_password)
+
+    try:
+        context.set_alpn_protocols(ALPN_PROTOCOLS)
+    except NotImplementedError:  # Defensive: in CI, we always have set_alpn_protocols
+        pass
+
+    ssl_sock = _ssl_wrap_socket_impl(sock, context, tls_in_tls, server_hostname)
+    return ssl_sock
+
+
+def is_ipaddress(hostname: str | bytes) -> bool:
+    """Detects whether the hostname given is an IPv4 or IPv6 address.
+    Also detects IPv6 addresses with Zone IDs.
+
+    :param str hostname: Hostname to examine.
+    :return: True if the hostname is an IP address, False otherwise.
+    """
+    if isinstance(hostname, bytes):
+        # IDN A-label bytes are ASCII compatible.
+        hostname = hostname.decode("ascii")
+    return bool(_IPV4_RE.match(hostname) or _BRACELESS_IPV6_ADDRZ_RE.match(hostname))
+
+
+def _is_key_file_encrypted(key_file: str) -> bool:
+    """Detects if a key file is encrypted or not."""
+    with open(key_file) as f:
+        for line in f:
+            # Look for Proc-Type: 4,ENCRYPTED
+            if "ENCRYPTED" in line:
+                return True
+
+    return False
+
+
+def _ssl_wrap_socket_impl(
+    sock: socket.socket,
+    ssl_context: ssl.SSLContext,
+    tls_in_tls: bool,
+    server_hostname: str | None = None,
+) -> ssl.SSLSocket | SSLTransportType:
+    if tls_in_tls:
+        if not SSLTransport:
+            # Import error, ssl is not available.
+            raise ProxySchemeUnsupported(
+                "TLS in TLS requires support for the 'ssl' module"
+            )
+
+        SSLTransport._validate_ssl_context_for_tls_in_tls(ssl_context)
+        return SSLTransport(sock, ssl_context, server_hostname)
+
+    return ssl_context.wrap_socket(sock, server_hostname=server_hostname)