make hmac (mostly) compatible with stdlib hmac
diff --git a/cryptography/hazmat/primitives/hmac.py b/cryptography/hazmat/primitives/hmac.py
index f635e36..c417cd2 100644
--- a/cryptography/hazmat/primitives/hmac.py
+++ b/cryptography/hazmat/primitives/hmac.py
@@ -19,34 +19,38 @@
class HMAC(object):
- def __init__(self, key, hash_cls, data=None, ctx=None, backend=None):
+ def __init__(self, key, msg=None, digestmod=None, ctx=None, backend=None):
super(HMAC, self).__init__()
if backend is None:
from cryptography.hazmat.bindings import _default_backend
backend = _default_backend
+
+ if digestmod is None:
+ raise ValueError("digestmod is a required argument")
+
self._backend = backend
- self.hash_cls = hash_cls
+ self.digestmod = digestmod
self.key = key
if ctx is None:
- self._ctx = self._backend.hmacs.create_ctx(key, self.hash_cls)
+ self._ctx = self._backend.hmacs.create_ctx(key, self.digestmod)
else:
self._ctx = ctx
- if data is not None:
- self.update(data)
+ if msg is not None:
+ self.update(msg)
- def update(self, data):
- if isinstance(data, six.text_type):
+ def update(self, msg):
+ if isinstance(msg, six.text_type):
raise TypeError("Unicode-objects must be encoded before hashing")
- self._backend.hmacs.update_ctx(self._ctx, data)
+ self._backend.hmacs.update_ctx(self._ctx, msg)
def copy(self):
- return self.__class__(self.key, hash_cls=self.hash_cls,
+ return self.__class__(self.key, digestmod=self.digestmod,
backend=self._backend, ctx=self._copy_ctx())
def digest(self):
return self._backend.hmacs.finalize_ctx(self._copy_ctx(),
- self.hash_cls.digest_size)
+ self.digestmod.digest_size)
def hexdigest(self):
return str(binascii.hexlify(self.digest()).decode("ascii"))
diff --git a/docs/hazmat/primitives/hmac.rst b/docs/hazmat/primitives/hmac.rst
index 47b8803..76b7e24 100644
--- a/docs/hazmat/primitives/hmac.rst
+++ b/docs/hazmat/primitives/hmac.rst
@@ -18,23 +18,23 @@
secret key. You can use an HMAC to verify integrity as well as authenticate a
message.
-.. class:: cryptography.primitives.hmac.HMAC(key, hash_cls, data=None)
+.. class:: cryptography.primitives.hmac.HMAC(key, msg=None, digestmod=None)
HMAC objects take a ``key``, a hash class derived from :class:`~cryptography.primitives.hashes.BaseHash`,
- and optional initial data. The ``key`` should be randomly generated bytes and
+ and optional msg. The ``key`` should be randomly generated bytes and
the length of the ``block_size`` of the hash. You must keep the ``key`` secret.
.. doctest::
>>> from cryptography.primitives import hashes, hmac
- >>> h = hmac.HMAC(key, hashes.SHA256)
+ >>> h = hmac.HMAC(key, digestmod=hashes.SHA256)
>>> h.update(b"message to hash")
>>> h.hexdigest()
'...'
- .. method:: update(data)
+ .. method:: update(msg)
- :param bytes data: The bytes you wish to hash.
+ :param bytes msg The bytes you wish to hash.
.. method:: copy()
diff --git a/tests/hazmat/primitives/test_hmac.py b/tests/hazmat/primitives/test_hmac.py
index e2b517a..81d9ac8 100644
--- a/tests/hazmat/primitives/test_hmac.py
+++ b/tests/hazmat/primitives/test_hmac.py
@@ -32,22 +32,26 @@
)
def test_hmac_reject_unicode(self, backend):
- h = hmac.HMAC(key=b"mykey", hash_cls=hashes.SHA1, backend=backend)
+ h = hmac.HMAC(key=b"mykey", digestmod=hashes.SHA1, backend=backend)
with pytest.raises(TypeError):
h.update(six.u("\u00FC"))
def test_base_hash_hexdigest_string_type(self, backend):
- h = hmac.HMAC(key=b"mykey", hash_cls=hashes.SHA1, backend=backend,
- data=b"")
+ h = hmac.HMAC(key=b"mykey", digestmod=hashes.SHA1, backend=backend,
+ msg=b"")
assert isinstance(h.hexdigest(), str)
+ def test_hmac_no_digestmod(self):
+ with pytest.raises(ValueError):
+ hmac.HMAC(key=b"shortkey")
+
class TestCopyHMAC(object):
def test_copy_backend_object(self):
pretend_hmac = pretend.stub(copy_ctx=lambda a: True)
pretend_backend = pretend.stub(hmacs=pretend_hmac)
pretend_ctx = pretend.stub()
- h = hmac.HMAC(b"key", hashes.SHA1, backend=pretend_backend,
+ h = hmac.HMAC(b"key", digestmod=hashes.SHA1, backend=pretend_backend,
ctx=pretend_ctx)
assert h._backend is pretend_backend
assert h.copy()._backend is pretend_backend
diff --git a/tests/hazmat/primitives/utils.py b/tests/hazmat/primitives/utils.py
index 73a2469..c51fef5 100644
--- a/tests/hazmat/primitives/utils.py
+++ b/tests/hazmat/primitives/utils.py
@@ -93,11 +93,11 @@
return test_base_hash
-def base_hash_test(backend, hash_cls, digest_size, block_size, only_if,
+def base_hash_test(backend, digestmod, digest_size, block_size, only_if,
skip_message):
if only_if is not None and not only_if(backend):
pytest.skip(skip_message)
- m = hash_cls(backend=backend)
+ m = digestmod(backend=backend)
assert m.digest_size == digest_size
assert m.block_size == block_size
m_copy = m.copy()
@@ -128,7 +128,7 @@
assert m.hexdigest() == md.lower()
-def generate_hmac_test(param_loader, path, file_names, hash_cls,
+def generate_hmac_test(param_loader, path, file_names, digestmod,
only_if=None, skip_message=None):
def test_hmac(self):
for backend in _ALL_BACKENDS:
@@ -137,7 +137,7 @@
yield (
hmac_test,
backend,
- hash_cls,
+ digestmod,
params,
only_if,
skip_message
@@ -145,17 +145,17 @@
return test_hmac
-def hmac_test(backend, hash_cls, params, only_if, skip_message):
+def hmac_test(backend, digestmod, params, only_if, skip_message):
if only_if is not None and not only_if(backend):
pytest.skip(skip_message)
msg = params[0]
md = params[1]
key = params[2]
- h = hmac.HMAC(binascii.unhexlify(key), hash_cls)
+ h = hmac.HMAC(binascii.unhexlify(key), digestmod=digestmod)
h.update(binascii.unhexlify(msg))
assert h.hexdigest() == md
- digest = hmac.HMAC(binascii.unhexlify(key), hash_cls,
- data=binascii.unhexlify(msg)).hexdigest()
+ digest = hmac.HMAC(binascii.unhexlify(key), digestmod=digestmod,
+ msg=binascii.unhexlify(msg)).hexdigest()
assert digest == md
@@ -172,11 +172,11 @@
return test_base_hmac
-def base_hmac_test(backend, hash_cls, only_if, skip_message):
+def base_hmac_test(backend, digestmod, only_if, skip_message):
if only_if is not None and not only_if(backend):
pytest.skip(skip_message)
key = b"ab"
- h = hmac.HMAC(binascii.unhexlify(key), hash_cls)
+ h = hmac.HMAC(binascii.unhexlify(key), digestmod=digestmod)
h_copy = h.copy()
assert h != h_copy
assert h._ctx != h_copy._ctx