keystone/keystone/tests/unit/receipt/test_fernet_provider.py

471 lines
18 KiB
Python

# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import base64
import datetime
import hashlib
import os
from unittest import mock
import uuid
from oslo_utils import timeutils
from keystone.common import fernet_utils
from keystone.common import provider_api
from keystone.common import utils
import keystone.conf
from keystone import exception
from keystone.identity.backends import resource_options as ro
from keystone.receipt.providers import fernet
from keystone.receipt import receipt_formatters
from keystone.tests import unit
from keystone.tests.unit import default_fixtures
from keystone.tests.unit import ksfixtures
from keystone.tests.unit.ksfixtures import database
from keystone.token import provider as token_provider
CONF = keystone.conf.CONF
PROVIDERS = provider_api.ProviderAPIs
class TestFernetReceiptProvider(unit.TestCase):
def setUp(self):
super(TestFernetReceiptProvider, self).setUp()
self.provider = fernet.Provider()
def test_invalid_receipt_raises_receipt_not_found(self):
receipt_id = uuid.uuid4().hex
e = self.assertRaises(
exception.ReceiptNotFound,
self.provider.validate_receipt,
receipt_id)
self.assertIn(receipt_id, u'%s' % e)
class TestValidate(unit.TestCase):
def setUp(self):
super(TestValidate, self).setUp()
self.useFixture(database.Database())
self.useFixture(
ksfixtures.ConfigAuthPlugins(
self.config_fixture,
['totp', 'token', 'password']))
self.load_backends()
PROVIDERS.resource_api.create_domain(
default_fixtures.ROOT_DOMAIN['id'], default_fixtures.ROOT_DOMAIN)
def config_overrides(self):
super(TestValidate, self).config_overrides()
self.config_fixture.config(group='receipt', provider='fernet')
def test_validate_v3_receipt_simple(self):
# Check the fields in the receipt result when use validate_v3_receipt
# with a simple receipt.
domain_ref = unit.new_domain_ref()
domain_ref = PROVIDERS.resource_api.create_domain(
domain_ref['id'], domain_ref
)
rule_list = [
['password', 'totp'],
['password', 'totp', 'token'],
]
user_ref = unit.new_user_ref(domain_ref['id'])
user_ref = PROVIDERS.identity_api.create_user(user_ref)
user_ref['options'][ro.MFA_RULES_OPT.option_name] = rule_list
user_ref['options'][ro.MFA_ENABLED_OPT.option_name] = True
PROVIDERS.identity_api.update_user(user_ref['id'], user_ref)
method_names = ['password']
receipt = PROVIDERS.receipt_provider_api.\
issue_receipt(user_ref['id'], method_names)
receipt = PROVIDERS.receipt_provider_api.validate_receipt(
receipt.id)
self.assertIsInstance(receipt.expires_at, str)
self.assertIsInstance(receipt.issued_at, str)
self.assertEqual(set(method_names), set(receipt.methods))
self.assertEqual(
set(frozenset(r) for r in rule_list),
set(frozenset(r) for r in
receipt.required_methods))
self.assertEqual(user_ref['id'], receipt.user_id)
def test_validate_v3_receipt_validation_error_exc(self):
# When the receipt format isn't recognized, ReceiptNotFound is raised.
# A uuid string isn't a valid Fernet receipt.
receipt_id = uuid.uuid4().hex
self.assertRaises(
exception.ReceiptNotFound,
PROVIDERS.receipt_provider_api.validate_receipt,
receipt_id
)
class TestReceiptFormatter(unit.TestCase):
def test_restore_padding(self):
# 'a' will result in '==' padding, 'aa' will result in '=' padding, and
# 'aaa' will result in no padding.
binary_to_test = [b'a', b'aa', b'aaa']
for binary in binary_to_test:
# base64.urlsafe_b64encode takes bytes and returns
# bytes.
encoded_string = base64.urlsafe_b64encode(binary)
encoded_string = encoded_string.decode('utf-8')
# encoded_string is now str.
encoded_str_without_padding = encoded_string.rstrip('=')
self.assertFalse(encoded_str_without_padding.endswith('='))
encoded_str_with_padding_restored = (
receipt_formatters.ReceiptFormatter.restore_padding(
encoded_str_without_padding)
)
self.assertEqual(encoded_string, encoded_str_with_padding_restored)
class TestPayloads(unit.TestCase):
def setUp(self):
super(TestPayloads, self).setUp()
self.useFixture(
ksfixtures.ConfigAuthPlugins(
self.config_fixture, ['totp', 'token', 'password']))
def assertTimestampsEqual(self, expected, actual):
# The timestamp that we get back when parsing the payload may not
# exactly match the timestamp that was put in the payload due to
# conversion to and from a float.
exp_time = timeutils.parse_isotime(expected)
actual_time = timeutils.parse_isotime(actual)
# the granularity of timestamp string is microseconds and it's only the
# last digit in the representation that's different, so use a delta
# just above nanoseconds.
return self.assertCloseEnoughForGovernmentWork(exp_time, actual_time,
delta=1e-05)
def test_strings_can_be_converted_to_bytes(self):
s = token_provider.random_urlsafe_str()
self.assertIsInstance(s, str)
b = receipt_formatters.ReceiptPayload.random_urlsafe_str_to_bytes(s)
self.assertIsInstance(b, bytes)
def test_uuid_hex_to_byte_conversions(self):
payload_cls = receipt_formatters.ReceiptPayload
expected_hex_uuid = uuid.uuid4().hex
uuid_obj = uuid.UUID(expected_hex_uuid)
expected_uuid_in_bytes = uuid_obj.bytes
actual_uuid_in_bytes = payload_cls.convert_uuid_hex_to_bytes(
expected_hex_uuid)
self.assertEqual(expected_uuid_in_bytes, actual_uuid_in_bytes)
actual_hex_uuid = payload_cls.convert_uuid_bytes_to_hex(
expected_uuid_in_bytes)
self.assertEqual(expected_hex_uuid, actual_hex_uuid)
def test_time_string_to_float_conversions(self):
payload_cls = receipt_formatters.ReceiptPayload
original_time_str = utils.isotime(subsecond=True)
time_obj = timeutils.parse_isotime(original_time_str)
expected_time_float = (
(timeutils.normalize_time(time_obj) -
datetime.datetime.utcfromtimestamp(0)).total_seconds())
# NOTE(lbragstad): The receipt expiration time for Fernet receipts is
# passed in the payload of the receipt. This is different from the
# receipt creation time, which is handled by Fernet and doesn't support
# subsecond precision because it is a timestamp integer.
self.assertIsInstance(expected_time_float, float)
actual_time_float = payload_cls._convert_time_string_to_float(
original_time_str)
self.assertIsInstance(actual_time_float, float)
self.assertEqual(expected_time_float, actual_time_float)
# Generate expected_time_str using the same time float. Using
# original_time_str from utils.isotime will occasionally fail due to
# floating point rounding differences.
time_object = datetime.datetime.utcfromtimestamp(actual_time_float)
expected_time_str = utils.isotime(time_object, subsecond=True)
actual_time_str = payload_cls._convert_float_to_time_string(
actual_time_float)
self.assertEqual(expected_time_str, actual_time_str)
def _test_payload(self, payload_class, exp_user_id=None, exp_methods=None):
exp_user_id = exp_user_id or uuid.uuid4().hex
exp_methods = exp_methods or ['password']
exp_expires_at = utils.isotime(timeutils.utcnow(), subsecond=True)
payload = payload_class.assemble(
exp_user_id, exp_methods, exp_expires_at)
(user_id, methods, expires_at) = payload_class.disassemble(payload)
self.assertEqual(exp_user_id, user_id)
self.assertEqual(exp_methods, methods)
self.assertTimestampsEqual(exp_expires_at, expires_at)
def test_payload(self):
self._test_payload(receipt_formatters.ReceiptPayload)
def test_payload_multiple_methods(self):
self._test_payload(
receipt_formatters.ReceiptPayload,
exp_methods=['password', 'totp'])
class TestFernetKeyRotation(unit.TestCase):
def setUp(self):
super(TestFernetKeyRotation, self).setUp()
# A collection of all previously-seen signatures of the key
# repository's contents.
self.key_repo_signatures = set()
@property
def keys(self):
"""Key files converted to numbers."""
return sorted(
int(x) for x in os.listdir(CONF.fernet_receipts.key_repository))
@property
def key_repository_size(self):
"""The number of keys in the key repository."""
return len(self.keys)
@property
def key_repository_signature(self):
"""Create a "thumbprint" of the current key repository.
Because key files are renamed, this produces a hash of the contents of
the key files, ignoring their filenames.
The resulting signature can be used, for example, to ensure that you
have a unique set of keys after you perform a key rotation (taking a
static set of keys, and simply shuffling them, would fail such a test).
"""
# Load the keys into a list, keys is list of str.
key_utils = fernet_utils.FernetUtils(
CONF.fernet_receipts.key_repository,
CONF.fernet_receipts.max_active_keys,
'fernet_receipts'
)
keys = key_utils.load_keys()
# Sort the list of keys by the keys themselves (they were previously
# sorted by filename).
keys.sort()
# Create the thumbprint using all keys in the repository.
signature = hashlib.sha1()
for key in keys:
# Need to convert key to bytes for update.
signature.update(key.encode('utf-8'))
return signature.hexdigest()
def assertRepositoryState(self, expected_size):
"""Validate the state of the key repository."""
self.assertEqual(expected_size, self.key_repository_size)
self.assertUniqueRepositoryState()
def assertUniqueRepositoryState(self):
"""Ensure that the current key repo state has not been seen before."""
# This is assigned to a variable because it takes some work to
# calculate.
signature = self.key_repository_signature
# Ensure the signature is not in the set of previously seen signatures.
self.assertNotIn(signature, self.key_repo_signatures)
# Add the signature to the set of repository signatures to validate
# that we don't see it again later.
self.key_repo_signatures.add(signature)
def test_rotation(self):
# Initializing a key repository results in this many keys. We don't
# support max_active_keys being set any lower.
min_active_keys = 2
# Simulate every rotation strategy up to "rotating once a week while
# maintaining a year's worth of keys."
for max_active_keys in range(min_active_keys, 52 + 1):
self.config_fixture.config(group='fernet_receipts',
max_active_keys=max_active_keys)
# Ensure that resetting the key repository always results in 2
# active keys.
self.useFixture(
ksfixtures.KeyRepository(
self.config_fixture,
'fernet_receipts',
CONF.fernet_receipts.max_active_keys
)
)
# Validate the initial repository state.
self.assertRepositoryState(expected_size=min_active_keys)
# The repository should be initialized with a staged key (0) and a
# primary key (1). The next key is just auto-incremented.
exp_keys = [0, 1]
next_key_number = exp_keys[-1] + 1 # keep track of next key
self.assertEqual(exp_keys, self.keys)
# Rotate the keys just enough times to fully populate the key
# repository.
key_utils = fernet_utils.FernetUtils(
CONF.fernet_receipts.key_repository,
CONF.fernet_receipts.max_active_keys,
'fernet_receipts'
)
for rotation in range(max_active_keys - min_active_keys):
key_utils.rotate_keys()
self.assertRepositoryState(expected_size=rotation + 3)
exp_keys.append(next_key_number)
next_key_number += 1
self.assertEqual(exp_keys, self.keys)
# We should have a fully populated key repository now.
self.assertEqual(max_active_keys, self.key_repository_size)
# Rotate an additional number of times to ensure that we maintain
# the desired number of active keys.
key_utils = fernet_utils.FernetUtils(
CONF.fernet_receipts.key_repository,
CONF.fernet_receipts.max_active_keys,
'fernet_receipts'
)
for rotation in range(10):
key_utils.rotate_keys()
self.assertRepositoryState(expected_size=max_active_keys)
exp_keys.pop(1)
exp_keys.append(next_key_number)
next_key_number += 1
self.assertEqual(exp_keys, self.keys)
def test_rotation_disk_write_fail(self):
# Make sure that the init key repository contains 2 keys
self.assertRepositoryState(expected_size=2)
key_utils = fernet_utils.FernetUtils(
CONF.fernet_receipts.key_repository,
CONF.fernet_receipts.max_active_keys,
'fernet_receipts'
)
# Simulate the disk full situation
mock_open = mock.mock_open()
file_handle = mock_open()
file_handle.flush.side_effect = IOError('disk full')
with mock.patch('keystone.common.fernet_utils.open', mock_open):
self.assertRaises(IOError, key_utils.rotate_keys)
# Assert that the key repository is unchanged
self.assertEqual(self.key_repository_size, 2)
with mock.patch('keystone.common.fernet_utils.open', mock_open):
self.assertRaises(IOError, key_utils.rotate_keys)
# Assert that the key repository is still unchanged, even after
# repeated rotation attempts.
self.assertEqual(self.key_repository_size, 2)
# Rotate the keys normally, without any mocking, to show that the
# system can recover.
key_utils.rotate_keys()
# Assert that the key repository is now expanded.
self.assertEqual(self.key_repository_size, 3)
def test_rotation_empty_file(self):
active_keys = 2
self.assertRepositoryState(expected_size=active_keys)
empty_file = os.path.join(CONF.fernet_receipts.key_repository, '2')
with open(empty_file, 'w'):
pass
key_utils = fernet_utils.FernetUtils(
CONF.fernet_receipts.key_repository,
CONF.fernet_receipts.max_active_keys,
'fernet_receipts'
)
# Rotate the keys to overwrite the empty file
key_utils.rotate_keys()
self.assertTrue(os.path.isfile(empty_file))
keys = key_utils.load_keys()
self.assertEqual(3, len(keys))
self.assertTrue(os.path.getsize(empty_file) > 0)
def test_non_numeric_files(self):
evil_file = os.path.join(CONF.fernet_receipts.key_repository, '99.bak')
with open(evil_file, 'w'):
pass
key_utils = fernet_utils.FernetUtils(
CONF.fernet_receipts.key_repository,
CONF.fernet_receipts.max_active_keys,
'fernet_receipts'
)
key_utils.rotate_keys()
self.assertTrue(os.path.isfile(evil_file))
keys = 0
for x in os.listdir(CONF.fernet_receipts.key_repository):
if x == '99.bak':
continue
keys += 1
self.assertEqual(3, keys)
class TestLoadKeys(unit.TestCase):
def assertValidFernetKeys(self, keys):
# Make sure each key is a non-empty string
for key in keys:
self.assertGreater(len(key), 0)
self.assertIsInstance(key, str)
def test_non_numeric_files(self):
evil_file = os.path.join(CONF.fernet_receipts.key_repository, '~1')
with open(evil_file, 'w'):
pass
key_utils = fernet_utils.FernetUtils(
CONF.fernet_receipts.key_repository,
CONF.fernet_receipts.max_active_keys,
'fernet_receipts'
)
keys = key_utils.load_keys()
self.assertEqual(2, len(keys))
self.assertValidFernetKeys(keys)
def test_empty_files(self):
empty_file = os.path.join(CONF.fernet_receipts.key_repository, '2')
with open(empty_file, 'w'):
pass
key_utils = fernet_utils.FernetUtils(
CONF.fernet_receipts.key_repository,
CONF.fernet_receipts.max_active_keys,
'fernet_receipts'
)
keys = key_utils.load_keys()
self.assertEqual(2, len(keys))
self.assertValidFernetKeys(keys)