"""JOSE utilities."""
try:
from collections.abc import Hashable, Mapping # pylint: disable=import-error
except ImportError:
from collections import Hashable, Mapping
import OpenSSL
import six
from cryptography.hazmat.primitives.asymmetric import rsa
class abstractclassmethod(classmethod):
# pylint: disable=invalid-name,too-few-public-methods
"""Descriptor for an abstract classmethod.
It augments the :mod:`abc` framework with an abstract
classmethod. This is implemented as :class:`abc.abstractclassmethod`
in the standard Python library starting with version 3.2.
This implementation is from a StackOverflow answer that was derived from
the implementation in the Python 3.3 abc library.
http://stackoverflow.com/questions/11217878/python-2-7-combine-abc-abstractmethod-and-classmethod.
"""
__isabstractmethod__ = True
def __init__(self, target):
target.__isabstractmethod__ = True
super(abstractclassmethod, self).__init__(target)
class ComparableX509(object): # pylint: disable=too-few-public-methods
"""Wrapper for OpenSSL.crypto.X509** objects that supports __eq__.
:ivar wrapped: Wrapped certificate or certificate request.
:type wrapped: `OpenSSL.crypto.X509` or `OpenSSL.crypto.X509Req`.
"""
def __init__(self, wrapped):
assert isinstance(wrapped, OpenSSL.crypto.X509) or isinstance(
wrapped, OpenSSL.crypto.X509Req)
self.wrapped = wrapped
def __getattr__(self, name):
return getattr(self.wrapped, name)
def _dump(self, filetype=OpenSSL.crypto.FILETYPE_ASN1):
"""Dumps the object into a buffer with the specified encoding.
:param int filetype: The desired encoding. Should be one of
`OpenSSL.crypto.FILETYPE_ASN1`,
`OpenSSL.crypto.FILETYPE_PEM`, or
`OpenSSL.crypto.FILETYPE_TEXT`.
:returns: Encoded X509 object.
:rtype: str
"""
if isinstance(self.wrapped, OpenSSL.crypto.X509):
func = OpenSSL.crypto.dump_certificate
else: # assert in __init__ makes sure this is X509Req
func = OpenSSL.crypto.dump_certificate_request
return func(filetype, self.wrapped)
def __eq__(self, other):
if not isinstance(other, self.__class__):
return NotImplemented
# pylint: disable=protected-access
return self._dump() == other._dump()
def __hash__(self):
return hash((self.__class__, self._dump()))
def __ne__(self, other):
return not self == other
def __repr__(self):
return '<{0}({1!r})>'.format(self.__class__.__name__, self.wrapped)
class ComparableKey(object): # pylint: disable=too-few-public-methods
"""Comparable wrapper for ``cryptography`` keys.
See https://github.com/pyca/cryptography/issues/2122.
"""
__hash__ = NotImplemented
def __init__(self, wrapped):
self._wrapped = wrapped
def __getattr__(self, name):
return getattr(self._wrapped, name)
def __eq__(self, other):
# pylint: disable=protected-access
if (not isinstance(other, self.__class__) or
self._wrapped.__class__ is not other._wrapped.__class__):
return NotImplemented
elif hasattr(self._wrapped, 'private_numbers'):
return self.private_numbers() == other.private_numbers()
elif hasattr(self._wrapped, 'public_numbers'):
return self.public_numbers() == other.public_numbers()
else:
return NotImplemented
def __ne__(self, other):
return not self == other
def __repr__(self):
return '<{0}({1!r})>'.format(self.__class__.__name__, self._wrapped)
def public_key(self):
"""Get wrapped public key."""
return self.__class__(self._wrapped.public_key())
class ComparableRSAKey(ComparableKey): # pylint: disable=too-few-public-methods
"""Wrapper for ``cryptography`` RSA keys.
Wraps around:
- :class:`~cryptography.hazmat.primitives.asymmetric.rsa.RSAPrivateKey`
- :class:`~cryptography.hazmat.primitives.asymmetric.rsa.RSAPublicKey`
"""
def __hash__(self):
# public_numbers() hasn't got stable hash!
# https://github.com/pyca/cryptography/issues/2143
if isinstance(self._wrapped, rsa.RSAPrivateKeyWithSerialization):
priv = self.private_numbers()
pub = priv.public_numbers
return hash((self.__class__, priv.p, priv.q, priv.dmp1,
priv.dmq1, priv.iqmp, pub.n, pub.e))
elif isinstance(self._wrapped, rsa.RSAPublicKeyWithSerialization):
pub = self.public_numbers()
return hash((self.__class__, pub.n, pub.e))
class ImmutableMap(Mapping, Hashable): # type: ignore
# pylint: disable=too-few-public-methods
"""Immutable key to value mapping with attribute access."""
__slots__ = ()
"""Must be overridden in subclasses."""
def __init__(self, **kwargs):
if set(kwargs) != set(self.__slots__):
raise TypeError(
'__init__() takes exactly the following arguments: {0} '
'({1} given)'.format(', '.join(self.__slots__),
', '.join(kwargs) if kwargs else 'none'))
for slot in self.__slots__:
object.__setattr__(self, slot, kwargs.pop(slot))
def update(self, **kwargs):
"""Return updated map."""
items = dict(self)
items.update(kwargs)
return type(self)(**items) # pylint: disable=star-args
def __getitem__(self, key):
try:
return getattr(self, key)
except AttributeError:
raise KeyError(key)
def __iter__(self):
return iter(self.__slots__)
def __len__(self):
return len(self.__slots__)
def __hash__(self):
return hash(tuple(getattr(self, slot) for slot in self.__slots__))
def __setattr__(self, name, value):
raise AttributeError("can't set attribute")
def __repr__(self):
return '{0}({1})'.format(self.__class__.__name__, ', '.join(
'{0}={1!r}'.format(key, value)
for key, value in six.iteritems(self)))
class frozendict(Mapping, Hashable): # type: ignore
# pylint: disable=invalid-name,too-few-public-methods
"""Frozen dictionary."""
__slots__ = ('_items', '_keys')
def __init__(self, *args, **kwargs):
if kwargs and not args:
items = dict(kwargs)
elif len(args) == 1 and isinstance(args[0], Mapping):
items = args[0]
else:
raise TypeError()
# TODO: support generators/iterators
object.__setattr__(self, '_items', items)
object.__setattr__(self, '_keys', tuple(sorted(six.iterkeys(items))))
def __getitem__(self, key):
return self._items[key]
def __iter__(self):
return iter(self._keys)
def __len__(self):
return len(self._items)
def _sorted_items(self):
return tuple((key, self[key]) for key in self._keys)
def __hash__(self):
return hash(self._sorted_items())
def __getattr__(self, name):
try:
return self._items[name]
except KeyError:
raise AttributeError(name)
def __setattr__(self, name, value):
raise AttributeError("can't set attribute")
def __repr__(self):
return 'frozendict({0})'.format(', '.join('{0}={1!r}'.format(
key, value) for key, value in self._sorted_items()))