Initial commit

venv/Lib/site-packages/cryptography/hazmat/bindings/openssl/binding.py

@@ -0,0 +1,121 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import annotations
+
+import os
+import sys
+import threading
+import types
+import typing
+import warnings
+
+import cryptography
+from cryptography.exceptions import InternalError
+from cryptography.hazmat.bindings._rust import _openssl, openssl
+from cryptography.hazmat.bindings.openssl._conditional import CONDITIONAL_NAMES
+
+
+def _openssl_assert(ok: bool) -> None:
+    if not ok:
+        errors = openssl.capture_error_stack()
+
+        raise InternalError(
+            "Unknown OpenSSL error. This error is commonly encountered when "
+            "another library is not cleaning up the OpenSSL error stack. If "
+            "you are using cryptography with another library that uses "
+            "OpenSSL try disabling it before reporting a bug. Otherwise "
+            "please file an issue at https://github.com/pyca/cryptography/"
+            "issues with information on how to reproduce "
+            f"this. ({errors!r})",
+            errors,
+        )
+
+
+def build_conditional_library(
+    lib: typing.Any,
+    conditional_names: dict[str, typing.Callable[[], list[str]]],
+) -> typing.Any:
+    conditional_lib = types.ModuleType("lib")
+    conditional_lib._original_lib = lib  # type: ignore[attr-defined]
+    excluded_names = set()
+    for condition, names_cb in conditional_names.items():
+        if not getattr(lib, condition):
+            excluded_names.update(names_cb())
+
+    for attr in dir(lib):
+        if attr not in excluded_names:
+            setattr(conditional_lib, attr, getattr(lib, attr))
+
+    return conditional_lib
+
+
+class Binding:
+    """
+    OpenSSL API wrapper.
+    """
+
+    lib: typing.ClassVar = None
+    ffi = _openssl.ffi
+    _lib_loaded = False
+    _init_lock = threading.Lock()
+
+    def __init__(self) -> None:
+        self._ensure_ffi_initialized()
+
+    @classmethod
+    def _ensure_ffi_initialized(cls) -> None:
+        with cls._init_lock:
+            if not cls._lib_loaded:
+                cls.lib = build_conditional_library(
+                    _openssl.lib, CONDITIONAL_NAMES
+                )
+                cls._lib_loaded = True
+
+    @classmethod
+    def init_static_locks(cls) -> None:
+        cls._ensure_ffi_initialized()
+
+
+def _verify_package_version(version: str) -> None:
+    # Occasionally we run into situations where the version of the Python
+    # package does not match the version of the shared object that is loaded.
+    # This may occur in environments where multiple versions of cryptography
+    # are installed and available in the python path. To avoid errors cropping
+    # up later this code checks that the currently imported package and the
+    # shared object that were loaded have the same version and raise an
+    # ImportError if they do not
+    so_package_version = _openssl.ffi.string(
+        _openssl.lib.CRYPTOGRAPHY_PACKAGE_VERSION
+    )
+    if version.encode("ascii") != so_package_version:
+        raise ImportError(
+            "The version of cryptography does not match the loaded "
+            "shared object. This can happen if you have multiple copies of "
+            "cryptography installed in your Python path. Please try creating "
+            "a new virtual environment to resolve this issue. "
+            f"Loaded python version: {version}, "
+            f"shared object version: {so_package_version}"
+        )
+
+    _openssl_assert(
+        _openssl.lib.OpenSSL_version_num() == openssl.openssl_version(),
+    )
+
+
+_verify_package_version(cryptography.__version__)
+
+Binding.init_static_locks()
+
+if (
+    sys.platform == "win32"
+    and os.environ.get("PROCESSOR_ARCHITEW6432") is not None
+):
+    warnings.warn(
+        "You are using cryptography on a 32-bit Python on a 64-bit Windows "
+        "Operating System. Cryptography will be significantly faster if you "
+        "switch to using a 64-bit Python.",
+        UserWarning,
+        stacklevel=2,
+    )