openstack/ironic
Code Issues Proposed changes

Change force_raw_images to use sha256 if md5 is selected

Browse Source 
In order to enable ironic's conductor to execute on nodes
set for FIPS 140-2 compliance, we need to not explicitly
choose MD5.

In the case of forcing images to raw, we were calculating
the checksum at least once, if not twice. Now we will honor
the original algorithm unless it is MD5, at which point we
will default to SHA3-256, and only recalculate the checksum
once.

Change-Id: I408a2e461bebf1f6d9fa3e350eb7ab1a3544adad
Story: 2007306
Task: 38791
This commit is contained in:
Julia Kreger 2020-02-18 11:56:10 -08:00
parent 5ebd7392ab
commit 06c5997267
3 changed files with 30 additions and 33 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
ironic/drivers/modules/deploy_utils.py
View File

@ -1300,19 +1300,22 @@ def build_instance_info_for_deploy(task):
force_raw=force_raw)
if force_raw:
instance_info['image_disk_format'] = 'raw'
# Standard behavior is for image_checksum to be MD5,
# so if the hash algorithm is None, then we will use
# sha256.
os_hash_algo = image_info.get('os_hash_algo')
if os_hash_algo == 'md5':
LOG.debug('Checksum calculation for image %(image)s is '
'set to \'%(algo)s\', changing to \'sha256\'',
{'algo': os_hash_algo,
'image': image_path})
os_hash_algo = 'sha256'
LOG.debug('Recalculating checksum for image %(image)s due to '
'image conversion.', {'image': image_path})
md5checksum = compute_image_checksum(image_path, 'md5')
instance_info['image_checksum'] = md5checksum
# Populate instance_info with os_hash_algo, os_hash_value
# if they exists and not md5
os_hash_algo = image_info['os_hash_algo']
if os_hash_algo and os_hash_algo != 'md5':
hash_value = compute_image_checksum(image_path,
os_hash_algo)
instance_info['image_os_hash_algo'] = os_hash_algo
instance_info['image_os_hash_value'] = hash_value
instance_info['image_checksum'] = 'md5-not-supported'
hash_value = compute_image_checksum(image_path, os_hash_algo)
instance_info['image_os_hash_algo'] = os_hash_algo
instance_info['image_os_hash_value'] = hash_value
else:
instance_info['image_checksum'] = image_info['checksum']
instance_info['image_disk_format'] = image_info['disk_format']

28
ironic/tests/unit/drivers/modules/test_deploy_utils.py
View File

@ -2641,37 +2641,21 @@ class TestBuildInstanceInfoForHttpProvisioning(db_base.DbTestCase):
image_path, instance_info = self._test_build_instance_info(
image_info=self.image_info, expect_raw=True)
self.assertEqual(instance_info['image_checksum'], 'fake-checksum')
self.assertEqual('md5-not-supported', instance_info['image_checksum'])
self.assertEqual(instance_info['image_disk_format'], 'raw')
calls = [mock.call(image_path, algorithm='md5'),
mock.call(image_path, algorithm='sha512')]
calls = [mock.call(image_path, algorithm='sha512')]
self.checksum_mock.assert_has_calls(calls)
def test_build_instance_info_force_raw_new_fields_none(self):
cfg.CONF.set_override('force_raw_images', True)
self.image_info['os_hash_algo'] = None
self.image_info['os_hash_value'] = None
image_path, instance_info = self._test_build_instance_info(
image_info=self.image_info, expect_raw=True)
self.assertEqual(instance_info['image_checksum'], 'fake-checksum')
self.assertEqual(instance_info['image_disk_format'], 'raw')
self.assertNotIn('image_os_hash_algo', instance_info.keys())
self.assertNotIn('image_os_hash_value', instance_info.keys())
self.checksum_mock.assert_called_once_with(image_path, algorithm='md5')
def test_build_instance_info_force_raw_new_fields_is_md5(self):
def test_build_instance_info_force_raw_drops_md5(self):
cfg.CONF.set_override('force_raw_images', True)
self.image_info['os_hash_algo'] = 'md5'
self.image_info['os_hash_value'] = 'fake-md5'
image_path, instance_info = self._test_build_instance_info(
image_info=self.image_info, expect_raw=True)
self.assertEqual(instance_info['image_checksum'], 'fake-checksum')
self.assertEqual('md5-not-supported', instance_info['image_checksum'])
self.assertEqual(instance_info['image_disk_format'], 'raw')
self.assertNotIn('image_os_hash_algo', instance_info.keys())
self.assertNotIn('image_os_hash_value', instance_info.keys())
self.checksum_mock.assert_called_once_with(image_path, algorithm='md5')
calls = [mock.call(image_path, algorithm='sha256')]
self.checksum_mock.assert_has_calls(calls)
class TestStorageInterfaceUtils(db_base.DbTestCase):

10
releasenotes/notes/image-checksum-recalculation-sha256-fd3d5b4b0b757e86.yaml Normal file
View File

@ -0,0 +1,10 @@
---
upgrade:
- |
If ``[DEFAULT]force_raw_images`` is set to ``true``, then MD5 will not be
utilized to recalculate the image checksum. This requires the
``ironic-python-agent`` ramdisk to be at least version 3.4.0.
security:
- |
Image checksum recalculation when images are forced to raw images, are now
calculated using SHA3-256 if MD5 was selected. This is now unconditional.