cpython/Lib/test/support/hashlib_helper.py

103 lines
3.3 KiB
Python

import functools
import hashlib
import unittest
from test.support.import_helper import import_module
try:
import _hashlib
except ImportError:
_hashlib = None
try:
import _hmac
except ImportError:
_hmac = None
def requires_hashlib():
return unittest.skipIf(_hashlib is None, "requires _hashlib")
def requires_builtin_hmac():
return unittest.skipIf(_hmac is None, "requires _hmac")
def _decorate_func_or_class(func_or_class, decorator_func):
if not isinstance(func_or_class, type):
return decorator_func(func_or_class)
decorated_class = func_or_class
setUpClass = decorated_class.__dict__.get('setUpClass')
if setUpClass is None:
def setUpClass(cls):
super(decorated_class, cls).setUpClass()
setUpClass.__qualname__ = decorated_class.__qualname__ + '.setUpClass'
setUpClass.__module__ = decorated_class.__module__
else:
setUpClass = setUpClass.__func__
setUpClass = classmethod(decorator_func(setUpClass))
decorated_class.setUpClass = setUpClass
return decorated_class
def requires_hashdigest(digestname, openssl=None, usedforsecurity=True):
"""Decorator raising SkipTest if a hashing algorithm is not available.
The hashing algorithm may be missing, blocked by a strict crypto policy,
or Python may be configured with `--with-builtin-hashlib-hashes=no`.
If 'openssl' is True, then the decorator checks that OpenSSL provides
the algorithm. Otherwise the check falls back to (optional) built-in
HACL* implementations.
The usedforsecurity flag is passed to the constructor but has no effect
on HACL* implementations.
Examples of exceptions being suppressed:
ValueError: [digital envelope routines: EVP_DigestInit_ex] disabled for FIPS
ValueError: unsupported hash type md4
"""
if openssl and _hashlib is not None:
def test_availability():
_hashlib.new(digestname, usedforsecurity=usedforsecurity)
else:
def test_availability():
hashlib.new(digestname, usedforsecurity=usedforsecurity)
def decorator_func(func):
@functools.wraps(func)
def wrapper(*args, **kwargs):
try:
test_availability()
except ValueError as exc:
msg = f"missing hash algorithm: {digestname!r}"
raise unittest.SkipTest(msg) from exc
return func(*args, **kwargs)
return wrapper
def decorator(func_or_class):
return _decorate_func_or_class(func_or_class, decorator_func)
return decorator
def requires_openssl_hashdigest(digestname, *, usedforsecurity=True):
"""Decorator raising SkipTest if an OpenSSL hashing algorithm is missing.
The hashing algorithm may be missing or blocked by a strict crypto policy.
"""
def decorator_func(func):
@requires_hashlib()
@functools.wraps(func)
def wrapper(*args, **kwargs):
try:
_hashlib.new(digestname, usedforsecurity=usedforsecurity)
except ValueError:
msg = f"missing OpenSSL hash algorithm: {digestname!r}"
raise unittest.SkipTest(msg)
return func(*args, **kwargs)
return wrapper
def decorator(func_or_class):
return _decorate_func_or_class(func_or_class, decorator_func)
return decorator