Load template files only from their known source

Modify get_class to ensure that user-defined resources cannot result in
reads from the local filesystem. Only resources defined by the operator
in the global environment should read local files.

To make this work, this patch also adds a separate
get_class_to_instantiate() method to the Environment.

We were previously using get_class for two different purposes - to get a
resource plugin on which we could perform introspection to obtain the
properties and attributes schema, and to get a resource plugin we could
instantiate to create a Resource object. These are both the same except in
the case of a TemplateResource, where having two different use cases for
the same piece of code was adding considerable extra complexity. Combining
the use cases in this way also made the error handling confusing (leading
to bug 1518458).

This change separates out the two cases.

Change-Id: I845e7d23c73242a4a4c9c40599690ab705c75caa
Closes-Bug: #1496277
Related-Bug: #1447194
Related-Bug: #1518458
Related-Bug: #1508115
(cherry picked from commit 06a713c445
                       and 26e6d5f6d7)
This commit is contained in:
Zane Bitter 2015-11-24 12:29:38 -05:00
parent 0a1daa7d2e
commit fa19a617a7
7 changed files with 51 additions and 31 deletions

View File

@ -112,6 +112,12 @@ class ResourceInfo(object):
def matches(self, resource_type):
return False
def get_class(self):
raise NotImplemented
def get_class_to_instantiate(self):
return self.get_class()
def __str__(self):
return '[%s](User:%s) %s -> %s' % (self.description,
self.user_resource,
@ -140,10 +146,20 @@ class TemplateResourceInfo(ResourceInfo):
def get_class(self):
from heat.engine.resources import template_resource
if self.user_resource:
allowed_schemes = template_resource.REMOTE_SCHEMES
else:
allowed_schemes = template_resource.LOCAL_SCHEMES
data = template_resource.TemplateResource.get_template_file(
self.template_name,
allowed_schemes)
env = self.registry.environment
return template_resource.generate_class(str(self.name),
self.template_name,
env)
return template_resource.generate_class_from_template(str(self.name),
data, env)
def get_class_to_instantiate(self):
from heat.engine.resources import template_resource
return template_resource.TemplateResource
class MapResourceInfo(ResourceInfo):
@ -398,6 +414,13 @@ class ResourceRegistry(object):
return match
def get_class(self, resource_type, resource_name=None):
info = self.get_resource_info(resource_type,
resource_name=resource_name)
if info is None:
raise exception.ResourceTypeNotFound(type_name=resource_type)
return info.get_class()
def get_class_to_instantiate(self, resource_type, resource_name=None):
if resource_type == "":
msg = _('Resource "%s" has no type') % resource_name
raise exception.StackValidationFailed(message=msg)
@ -414,7 +437,7 @@ class ResourceRegistry(object):
if info is None:
msg = _("Unknown resource Type : %s") % resource_type
raise exception.StackValidationFailed(message=msg)
return info.get_class()
return info.get_class_to_instantiate()
def as_dict(self):
"""Return user resources in a dict format."""
@ -521,6 +544,10 @@ class Environment(object):
def get_class(self, resource_type, resource_name=None):
return self.registry.get_class(resource_type, resource_name)
def get_class_to_instantiate(self, resource_type, resource_name=None):
return self.registry.get_class_to_instantiate(resource_type,
resource_name)
def get_types(self, support_status=None):
return self.registry.get_types(support_status)

View File

@ -137,14 +137,11 @@ class Resource(object):
# Call is already for a subclass, so pass it through
ResourceClass = cls
else:
from heat.engine.resources import template_resource
registry = stack.env.registry
try:
ResourceClass = registry.get_class(definition.resource_type,
resource_name=name)
except exception.NotFound:
ResourceClass = template_resource.TemplateResource
ResourceClass = registry.get_class_to_instantiate(
definition.resource_type,
resource_name=name)
assert issubclass(ResourceClass, Resource)
return super(Resource, cls).__new__(ResourceClass)

View File

@ -193,11 +193,7 @@ class ResourceGroup(stack_resource.StackResource):
val_templ = template.Template(test_tmpl)
res_def = val_templ.resource_definitions(self.stack)["0"]
# make sure we can resolve the nested resource type
try:
self.stack.env.get_class(res_def.resource_type)
except exception.NotFound:
# its a template resource
pass
self.stack.env.get_class_to_instantiate(res_def.resource_type)
try:
name = "%s-%s" % (self.stack.name, self.name)

View File

@ -26,8 +26,11 @@ from heat.engine.resources import stack_resource
from heat.engine import template
def generate_class(name, template_name, env):
data = TemplateResource.get_template_file(template_name, ('file',))
REMOTE_SCHEMES = ('http', 'https')
LOCAL_SCHEMES = ('file',)
def generate_class_from_template(name, data, env):
tmpl = template.Template(template_format.parse(data))
props, attrs = TemplateResource.get_schemas(tmpl, env.param_defaults)
cls = type(name, (TemplateResource,),
@ -79,9 +82,9 @@ class TemplateResource(stack_resource.StackResource):
self.template_name = tri.template_name
self.resource_type = tri.name
if tri.user_resource:
self.allowed_schemes = ('http', 'https')
self.allowed_schemes = REMOTE_SCHEMES
else:
self.allowed_schemes = ('http', 'https', 'file')
self.allowed_schemes = REMOTE_SCHEMES + LOCAL_SCHEMES
return tri

View File

@ -989,8 +989,6 @@ class EngineService(service.Service):
"""
try:
resource_class = resources.global_env().get_class(type_name)
except exception.StackValidationFailed:
raise exception.ResourceTypeNotFound(type_name=type_name)
except exception.NotFound as ex:
raise exception.StackValidationFailed(message=ex.message)
@ -1021,8 +1019,6 @@ class EngineService(service.Service):
try:
return resources.global_env().get_class(
type_name).resource_to_template(type_name)
except exception.StackValidationFailed:
raise exception.ResourceTypeNotFound(type_name=type_name)
except exception.NotFound as ex:
raise exception.StackValidationFailed(message=ex.message)

View File

@ -613,7 +613,11 @@ class ProviderTemplateTest(common.HeatTestCase):
env_str = {'resource_registry': {'resources': {'fred': {
"OS::ResourceType": test_templ_name}}}}
env = environment.Environment(env_str)
global_env = environment.Environment({}, user_env=False)
global_env.load(env_str)
with mock.patch('heat.engine.resources._environment',
global_env):
env = environment.Environment({})
cls = env.get_class('OS::ResourceType', 'fred')
self.assertNotEqual(template_resource.TemplateResource, cls)
self.assertTrue(issubclass(cls, template_resource.TemplateResource))
@ -639,10 +643,6 @@ class ProviderTemplateTest(common.HeatTestCase):
test_templ = test_templ_file.read()
self.assertTrue(test_templ, "Empty test template")
self.m.StubOutWithMock(urlfetch, "get")
urlfetch.get(test_templ_name,
allowed_schemes=('file',)
).AndRaise(urlfetch.URLFetchError(
_('Failed to retrieve template')))
urlfetch.get(test_templ_name,
allowed_schemes=('http', 'https')).AndReturn(test_templ)
parsed_test_templ = template_format.parse(test_templ)

View File

@ -67,12 +67,13 @@ class ResourceTest(common.HeatTestCase):
self.patch('heat.engine.resource.warnings')
def test_get_class_ok(self):
cls = resources.global_env().get_class('GenericResourceType')
cls = resources.global_env().get_class_to_instantiate(
'GenericResourceType')
self.assertEqual(generic_rsrc.GenericResource, cls)
def test_get_class_noexist(self):
self.assertRaises(exception.StackValidationFailed,
resources.global_env().get_class,
resources.global_env().get_class_to_instantiate,
'NoExistResourceType')
def test_resource_new_ok(self):