diff options
Diffstat (limited to 'Lib/test/support/hashlib_helper.py')
-rw-r--r-- | Lib/test/support/hashlib_helper.py | 221 |
1 files changed, 214 insertions, 7 deletions
diff --git a/Lib/test/support/hashlib_helper.py b/Lib/test/support/hashlib_helper.py index 5043f08dd93..7032257b068 100644 --- a/Lib/test/support/hashlib_helper.py +++ b/Lib/test/support/hashlib_helper.py @@ -23,6 +23,22 @@ def requires_builtin_hmac(): return unittest.skipIf(_hmac is None, "requires _hmac") +def _missing_hash(digestname, implementation=None, *, exc=None): + parts = ["missing", implementation, f"hash algorithm: {digestname!r}"] + msg = " ".join(filter(None, parts)) + raise unittest.SkipTest(msg) from exc + + +def _openssl_availabillity(digestname, *, usedforsecurity): + try: + _hashlib.new(digestname, usedforsecurity=usedforsecurity) + except AttributeError: + assert _hashlib is None + _missing_hash(digestname, "OpenSSL") + except ValueError as exc: + _missing_hash(digestname, "OpenSSL", exc=exc) + + def _decorate_func_or_class(func_or_class, decorator_func): if not isinstance(func_or_class, type): return decorator_func(func_or_class) @@ -71,8 +87,7 @@ def requires_hashdigest(digestname, openssl=None, usedforsecurity=True): try: test_availability() except ValueError as exc: - msg = f"missing hash algorithm: {digestname!r}" - raise unittest.SkipTest(msg) from exc + _missing_hash(digestname, exc=exc) return func(*args, **kwargs) return wrapper @@ -87,14 +102,44 @@ def requires_openssl_hashdigest(digestname, *, usedforsecurity=True): The hashing algorithm may be missing or blocked by a strict crypto policy. """ def decorator_func(func): - @requires_hashlib() + @requires_hashlib() # avoid checking at each call @functools.wraps(func) def wrapper(*args, **kwargs): + _openssl_availabillity(digestname, usedforsecurity=usedforsecurity) + return func(*args, **kwargs) + return wrapper + + def decorator(func_or_class): + return _decorate_func_or_class(func_or_class, decorator_func) + return decorator + + +def find_openssl_hashdigest_constructor(digestname, *, usedforsecurity=True): + """Find the OpenSSL hash function constructor by its name.""" + assert isinstance(digestname, str), digestname + _openssl_availabillity(digestname, usedforsecurity=usedforsecurity) + # This returns a function of the form _hashlib.openssl_<name> and + # not a lambda function as it is rejected by _hashlib.hmac_new(). + return getattr(_hashlib, f"openssl_{digestname}") + + +def requires_builtin_hashdigest( + module_name, digestname, *, usedforsecurity=True +): + """Decorator raising SkipTest if a HACL* hashing algorithm is missing. + + - The *module_name* is the C extension module name based on HACL*. + - The *digestname* is one of its member, e.g., 'md5'. + """ + def decorator_func(func): + @functools.wraps(func) + def wrapper(*args, **kwargs): + module = import_module(module_name) try: - _hashlib.new(digestname, usedforsecurity=usedforsecurity) - except ValueError: - msg = f"missing OpenSSL hash algorithm: {digestname!r}" - raise unittest.SkipTest(msg) + getattr(module, digestname) + except AttributeError: + fullname = f'{module_name}.{digestname}' + _missing_hash(fullname, implementation="HACL") return func(*args, **kwargs) return wrapper @@ -103,6 +148,168 @@ def requires_openssl_hashdigest(digestname, *, usedforsecurity=True): return decorator +def find_builtin_hashdigest_constructor( + module_name, digestname, *, usedforsecurity=True +): + """Find the HACL* hash function constructor. + + - The *module_name* is the C extension module name based on HACL*. + - The *digestname* is one of its member, e.g., 'md5'. + """ + module = import_module(module_name) + try: + constructor = getattr(module, digestname) + constructor(b'', usedforsecurity=usedforsecurity) + except (AttributeError, TypeError, ValueError): + _missing_hash(f'{module_name}.{digestname}', implementation="HACL") + return constructor + + +class HashFunctionsTrait: + """Mixin trait class containing hash functions. + + This class is assumed to have all unitest.TestCase methods but should + not directly inherit from it to prevent the test suite being run on it. + + Subclasses should implement the hash functions by returning an object + that can be recognized as a valid digestmod parameter for both hashlib + and HMAC. In particular, it cannot be a lambda function as it will not + be recognized by hashlib (it will still be accepted by the pure Python + implementation of HMAC). + """ + + ALGORITHMS = [ + 'md5', 'sha1', + 'sha224', 'sha256', 'sha384', 'sha512', + 'sha3_224', 'sha3_256', 'sha3_384', 'sha3_512', + ] + + # Default 'usedforsecurity' to use when looking up a hash function. + usedforsecurity = True + + def _find_constructor(self, name): + # By default, a missing algorithm skips the test that uses it. + self.assertIn(name, self.ALGORITHMS) + self.skipTest(f"missing hash function: {name}") + + @property + def md5(self): + return self._find_constructor("md5") + + @property + def sha1(self): + return self._find_constructor("sha1") + + @property + def sha224(self): + return self._find_constructor("sha224") + + @property + def sha256(self): + return self._find_constructor("sha256") + + @property + def sha384(self): + return self._find_constructor("sha384") + + @property + def sha512(self): + return self._find_constructor("sha512") + + @property + def sha3_224(self): + return self._find_constructor("sha3_224") + + @property + def sha3_256(self): + return self._find_constructor("sha3_256") + + @property + def sha3_384(self): + return self._find_constructor("sha3_384") + + @property + def sha3_512(self): + return self._find_constructor("sha3_512") + + +class NamedHashFunctionsTrait(HashFunctionsTrait): + """Trait containing named hash functions. + + Hash functions are available if and only if they are available in hashlib. + """ + + def _find_constructor(self, name): + self.assertIn(name, self.ALGORITHMS) + return name + + +class OpenSSLHashFunctionsTrait(HashFunctionsTrait): + """Trait containing OpenSSL hash functions. + + Hash functions are available if and only if they are available in _hashlib. + """ + + def _find_constructor(self, name): + self.assertIn(name, self.ALGORITHMS) + return find_openssl_hashdigest_constructor( + name, usedforsecurity=self.usedforsecurity + ) + + +class BuiltinHashFunctionsTrait(HashFunctionsTrait): + """Trait containing HACL* hash functions. + + Hash functions are available if and only if they are available in C. + In particular, HACL* HMAC-MD5 may be available even though HACL* md5 + is not since the former is unconditionally built. + """ + + def _find_constructor_in(self, module, name): + self.assertIn(name, self.ALGORITHMS) + return find_builtin_hashdigest_constructor(module, name) + + @property + def md5(self): + return self._find_constructor_in("_md5", "md5") + + @property + def sha1(self): + return self._find_constructor_in("_sha1", "sha1") + + @property + def sha224(self): + return self._find_constructor_in("_sha2", "sha224") + + @property + def sha256(self): + return self._find_constructor_in("_sha2", "sha256") + + @property + def sha384(self): + return self._find_constructor_in("_sha2", "sha384") + + @property + def sha512(self): + return self._find_constructor_in("_sha2", "sha512") + + @property + def sha3_224(self): + return self._find_constructor_in("_sha3", "sha3_224") + + @property + def sha3_256(self): + return self._find_constructor_in("_sha3","sha3_256") + + @property + def sha3_384(self): + return self._find_constructor_in("_sha3","sha3_384") + + @property + def sha3_512(self): + return self._find_constructor_in("_sha3","sha3_512") + + def find_gil_minsize(modules_names, default=2048): """Get the largest GIL_MINSIZE value for the given cryptographic modules. |