Merge in update openstack-common policy code
Updates Glance-specific policy glue code to eliminate deprecated openstack-common policy interfaces. Also cleans up policy code to allow for returning fine-grained policy values. Change-Id: I2951a0de3751bd2ec868e7a661070fed624e4af2
This commit is contained in:
parent
3e532bb746
commit
1e49c857db
@ -1,4 +1,4 @@
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{
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"default": [],
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"manage_image_cache": [["role:admin"]]
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"default": "",
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"manage_image_cache": "role:admin"
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}
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@ -37,8 +37,8 @@ CONF.register_opts(policy_opts)
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DEFAULT_RULES = {
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'default': [[]],
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'manage_image_cache': [['role:admin']]
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'default': policy.TrueCheck(),
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'manage_image_cache': policy.RoleCheck('role', 'admin'),
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}
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@ -52,18 +52,23 @@ class Enforcer(object):
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self.policy_file_contents = None
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def set_rules(self, rules):
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"""Create a new Brain based on the provided dict of rules"""
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brain = policy.Brain(rules, self.default_rule)
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policy.set_brain(brain)
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"""Create a new Rules object based on the provided dict of rules"""
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rules_obj = policy.Rules(rules, self.default_rule)
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policy.set_rules(rules_obj)
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def load_rules(self):
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"""Set the rules found in the json file on disk"""
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if self.policy_path:
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rules = self._read_policy_file()
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LOG.debug(_('Loaded policy rules: %s') % rules)
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rule_type = ""
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else:
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rules = DEFAULT_RULES
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LOG.debug(_('Using default policy rules: %s') % rules)
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rule_type = "default "
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text_rules = dict((k, str(v)) for k, v in rules.items())
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LOG.debug(_('Loaded %(rule_type)spolicy rules: %(text_rules)s') %
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locals())
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self.set_rules(rules)
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@staticmethod
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@ -86,10 +91,32 @@ class Enforcer(object):
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LOG.debug(_("Loading policy from %s") % self.policy_path)
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with open(self.policy_path) as fap:
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raw_contents = fap.read()
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self.policy_file_contents = json.loads(raw_contents)
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rules_dict = json.loads(raw_contents)
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self.policy_file_contents = dict(
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(k, policy.parse_rule(v))
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for k, v in rules_dict.items())
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self.policy_file_mtime = mtime
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return self.policy_file_contents
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def _check(self, context, rule, target, *args, **kwargs):
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"""Verifies that the action is valid on the target in this context.
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:param context: Glance request context
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:param rule: String representing the action to be checked
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:param object: Dictionary representing the object of the action.
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:raises: `glance.common.exception.Forbidden`
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:returns: A non-False value if access is allowed.
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"""
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self.load_rules()
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credentials = {
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'roles': context.roles,
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'user': context.user,
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'tenant': context.tenant,
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}
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return policy.check(rule, target, credentials, *args, **kwargs)
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def enforce(self, context, action, target):
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"""Verifies that the action is valid on the target in this context.
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@ -97,16 +124,17 @@ class Enforcer(object):
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:param action: String representing the action to be checked
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:param object: Dictionary representing the object of the action.
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:raises: `glance.common.exception.Forbidden`
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:returns: None
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:returns: A non-False value if access is allowed.
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"""
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self.load_rules()
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return self._check(context, action, target,
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exception.Forbidden, action=action)
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match_list = ('rule:%s' % action,)
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credentials = {
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'roles': context.roles,
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'user': context.user,
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'tenant': context.tenant,
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}
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def check(self, context, action, target):
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"""Verifies that the action is valid on the target in this context.
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policy.enforce(match_list, target, credentials,
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exception.Forbidden, action=action)
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:param context: Glance request context
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:param action: String representing the action to be checked
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:param object: Dictionary representing the object of the action.
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:returns: A non-False value if access is allowed.
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"""
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return self._check(context, action, target)
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@ -1,6 +1,6 @@
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# vim: tabstop=4 shiftwidth=4 softtabstop=4
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# Copyright (c) 2011 OpenStack, LLC.
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# Copyright (c) 2012 OpenStack, LLC.
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# All Rights Reserved.
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#
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# Licensed under the Apache License, Version 2.0 (the "License"); you may
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@ -15,10 +15,52 @@
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# License for the specific language governing permissions and limitations
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# under the License.
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"""Common Policy Engine Implementation"""
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"""
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Common Policy Engine Implementation
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Policies can be expressed in one of two forms: A list of lists, or a
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string written in the new policy language.
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In the list-of-lists representation, each check inside the innermost
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list is combined as with an "and" conjunction--for that check to pass,
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all the specified checks must pass. These innermost lists are then
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combined as with an "or" conjunction. This is the original way of
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expressing policies, but there now exists a new way: the policy
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language.
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In the policy language, each check is specified the same way as in the
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list-of-lists representation: a simple "a:b" pair that is matched to
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the correct code to perform that check. However, conjunction
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operators are available, allowing for more expressiveness in crafting
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policies.
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As an example, take the following rule, expressed in the list-of-lists
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representation::
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[["role:admin"], ["project_id:%(project_id)s", "role:projectadmin"]]
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In the policy language, this becomes::
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role:admin or (project_id:%(project_id)s and role:projectadmin)
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The policy language also has the "not" operator, allowing a richer
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policy rule::
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project_id:%(project_id)s and not role:dunce
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Finally, two special policy checks should be mentioned; the policy
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check "@" will always accept an access, and the policy check "!" will
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always reject an access. (Note that if a rule is either the empty
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list ("[]") or the empty string, this is equivalent to the "@" policy
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check.) Of these, the "!" policy check is probably the most useful,
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as it allows particular rules to be explicitly disabled.
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"""
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import abc
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import logging
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import re
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import urllib
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import urllib2
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from glance.openstack.common.gettextutils import _
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@ -28,217 +70,650 @@ from glance.openstack.common import jsonutils
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LOG = logging.getLogger(__name__)
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_BRAIN = None
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_rules = None
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_checks = {}
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def set_brain(brain):
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"""Set the brain used by enforce().
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Defaults use Brain() if not set.
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class Rules(dict):
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"""
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global _BRAIN
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_BRAIN = brain
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def reset():
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"""Clear the brain used by enforce()."""
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global _BRAIN
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_BRAIN = None
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def enforce(match_list, target_dict, credentials_dict, exc=None,
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*args, **kwargs):
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"""Enforces authorization of some rules against credentials.
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:param match_list: nested tuples of data to match against
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The basic brain supports three types of match lists:
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1) rules
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looks like: ``('rule:compute:get_instance',)``
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Retrieves the named rule from the rules dict and recursively
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checks against the contents of the rule.
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2) roles
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looks like: ``('role:compute:admin',)``
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Matches if the specified role is in credentials_dict['roles'].
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3) generic
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looks like: ``('tenant_id:%(tenant_id)s',)``
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Substitutes values from the target dict into the match using
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the % operator and matches them against the creds dict.
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Combining rules:
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The brain returns True if any of the outer tuple of rules
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match and also True if all of the inner tuples match. You
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can use this to perform simple boolean logic. For
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example, the following rule would return True if the creds
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contain the role 'admin' OR the if the tenant_id matches
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the target dict AND the the creds contains the role
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'compute_sysadmin':
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::
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{
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"rule:combined": (
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'role:admin',
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('tenant_id:%(tenant_id)s', 'role:compute_sysadmin')
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)
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}
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Note that rule and role are reserved words in the credentials match, so
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you can't match against properties with those names. Custom brains may
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also add new reserved words. For example, the HttpBrain adds http as a
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reserved word.
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:param target_dict: dict of object properties
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Target dicts contain as much information as we can about the object being
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operated on.
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:param credentials_dict: dict of actor properties
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Credentials dicts contain as much information as we can about the user
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performing the action.
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:param exc: exception to raise
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Class of the exception to raise if the check fails. Any remaining
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arguments passed to enforce() (both positional and keyword arguments)
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will be passed to the exception class. If exc is not provided, returns
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False.
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:return: True if the policy allows the action
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:return: False if the policy does not allow the action and exc is not set
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A store for rules. Handles the default_rule setting directly.
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"""
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global _BRAIN
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if not _BRAIN:
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_BRAIN = Brain()
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if not _BRAIN.check(match_list, target_dict, credentials_dict):
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if exc:
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raise exc(*args, **kwargs)
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return False
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return True
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class Brain(object):
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"""Implements policy checking."""
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_checks = {}
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@classmethod
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def _register(cls, name, func):
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cls._checks[name] = func
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@classmethod
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def load_json(cls, data, default_rule=None):
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"""Init a brain using json instead of a rules dictionary."""
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rules_dict = jsonutils.loads(data)
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return cls(rules=rules_dict, default_rule=default_rule)
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"""
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Allow loading of JSON rule data.
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"""
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# Suck in the JSON data and parse the rules
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rules = dict((k, parse_rule(v)) for k, v in
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jsonutils.loads(data).items())
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return cls(rules, default_rule)
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def __init__(self, rules=None, default_rule=None):
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if self.__class__ != Brain:
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LOG.warning(_("Inheritance-based rules are deprecated; use "
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"the default brain instead of %s.") %
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self.__class__.__name__)
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"""Initialize the Rules store."""
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self.rules = rules or {}
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super(Rules, self).__init__(rules or {})
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self.default_rule = default_rule
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def add_rule(self, key, match):
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self.rules[key] = match
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def __missing__(self, key):
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"""Implements the default rule handling."""
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def _check(self, match, target_dict, cred_dict):
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# If the default rule isn't actually defined, do something
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# reasonably intelligent
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if not self.default_rule or self.default_rule not in self:
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raise KeyError(key)
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return self[self.default_rule]
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def __str__(self):
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"""Dumps a string representation of the rules."""
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# Start by building the canonical strings for the rules
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out_rules = {}
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for key, value in self.items():
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# Use empty string for singleton TrueCheck instances
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if isinstance(value, TrueCheck):
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out_rules[key] = ''
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else:
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out_rules[key] = str(value)
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# Dump a pretty-printed JSON representation
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return jsonutils.dumps(out_rules, indent=4)
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# Really have to figure out a way to deprecate this
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def set_rules(rules):
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"""Set the rules in use for policy checks."""
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global _rules
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_rules = rules
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# Ditto
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def reset():
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"""Clear the rules used for policy checks."""
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global _rules
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_rules = None
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def check(rule, target, creds, exc=None, *args, **kwargs):
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"""
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Checks authorization of a rule against the target and credentials.
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:param rule: The rule to evaluate.
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:param target: As much information about the object being operated
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on as possible, as a dictionary.
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:param creds: As much information about the user performing the
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action as possible, as a dictionary.
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:param exc: Class of the exception to raise if the check fails.
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Any remaining arguments passed to check() (both
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positional and keyword arguments) will be passed to
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the exception class. If exc is not provided, returns
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False.
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:return: Returns False if the policy does not allow the action and
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exc is not provided; otherwise, returns a value that
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evaluates to True. Note: for rules using the "case"
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expression, this True value will be the specified string
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from the expression.
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"""
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# Allow the rule to be a Check tree
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if isinstance(rule, BaseCheck):
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result = rule(target, creds)
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elif not _rules:
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# No rules to reference means we're going to fail closed
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result = False
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else:
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try:
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match_kind, match_value = match.split(':', 1)
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except Exception:
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LOG.exception(_("Failed to understand rule %(match)r") % locals())
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# If the rule is invalid, fail closed
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return False
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# Evaluate the rule
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result = _rules[rule](target, creds)
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except KeyError:
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# If the rule doesn't exist, fail closed
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result = False
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func = None
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try:
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old_func = getattr(self, '_check_%s' % match_kind)
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except AttributeError:
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func = self._checks.get(match_kind, self._checks.get(None, None))
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else:
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LOG.warning(_("Inheritance-based rules are deprecated; update "
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"_check_%s") % match_kind)
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func = (lambda brain, kind, value, target, cred:
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old_func(value, target, cred))
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# If it is False, raise the exception if requested
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if exc and result is False:
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raise exc(*args, **kwargs)
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if not func:
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LOG.error(_("No handler for matches of kind %s") % match_kind)
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# Fail closed
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return False
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return result
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return func(self, match_kind, match_value, target_dict, cred_dict)
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def check(self, match_list, target_dict, cred_dict):
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"""Checks authorization of some rules against credentials.
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class BaseCheck(object):
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"""
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Abstract base class for Check classes.
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"""
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Detailed description of the check with examples in policy.enforce().
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:param match_list: nested tuples of data to match against
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:param target_dict: dict of object properties
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:param credentials_dict: dict of actor properties
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:returns: True if the check passes
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__metaclass__ = abc.ABCMeta
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@abc.abstractmethod
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def __str__(self):
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"""
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if not match_list:
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return True
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for and_list in match_list:
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if isinstance(and_list, basestring):
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and_list = (and_list,)
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if all([self._check(item, target_dict, cred_dict)
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for item in and_list]):
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return True
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Retrieve a string representation of the Check tree rooted at
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this node.
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"""
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pass
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@abc.abstractmethod
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def __call__(self, target, cred):
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"""
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Perform the check. Returns False to reject the access or a
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true value (not necessary True) to accept the access.
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"""
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pass
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class FalseCheck(BaseCheck):
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"""
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A policy check that always returns False (disallow).
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"""
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def __str__(self):
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"""Return a string representation of this check."""
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return "!"
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def __call__(self, target, cred):
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"""Check the policy."""
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return False
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class HttpBrain(Brain):
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"""A brain that can check external urls for policy.
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|
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Posts json blobs for target and credentials.
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Note that this brain is deprecated; the http check is registered
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by default.
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class TrueCheck(BaseCheck):
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"""
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A policy check that always returns True (allow).
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"""
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pass
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def __str__(self):
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"""Return a string representation of this check."""
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return "@"
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def __call__(self, target, cred):
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"""Check the policy."""
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return True
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class Check(BaseCheck):
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"""
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A base class to allow for user-defined policy checks.
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"""
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def __init__(self, kind, match):
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"""
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:param kind: The kind of the check, i.e., the field before the
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':'.
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:param match: The match of the check, i.e., the field after
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the ':'.
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"""
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self.kind = kind
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self.match = match
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def __str__(self):
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"""Return a string representation of this check."""
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||||
|
||||
return "%s:%s" % (self.kind, self.match)
|
||||
|
||||
|
||||
class NotCheck(BaseCheck):
|
||||
"""
|
||||
A policy check that inverts the result of another policy check.
|
||||
Implements the "not" operator.
|
||||
"""
|
||||
|
||||
def __init__(self, rule):
|
||||
"""
|
||||
Initialize the 'not' check.
|
||||
|
||||
:param rule: The rule to negate. Must be a Check.
|
||||
"""
|
||||
|
||||
self.rule = rule
|
||||
|
||||
def __str__(self):
|
||||
"""Return a string representation of this check."""
|
||||
|
||||
return "not %s" % self.rule
|
||||
|
||||
def __call__(self, target, cred):
|
||||
"""
|
||||
Check the policy. Returns the logical inverse of the wrapped
|
||||
check.
|
||||
"""
|
||||
|
||||
return not self.rule(target, cred)
|
||||
|
||||
|
||||
class AndCheck(BaseCheck):
|
||||
"""
|
||||
A policy check that requires that a list of other checks all
|
||||
return True. Implements the "and" operator.
|
||||
"""
|
||||
|
||||
def __init__(self, rules):
|
||||
"""
|
||||
Initialize the 'and' check.
|
||||
|
||||
:param rules: A list of rules that will be tested.
|
||||
"""
|
||||
|
||||
self.rules = rules
|
||||
|
||||
def __str__(self):
|
||||
"""Return a string representation of this check."""
|
||||
|
||||
return "(%s)" % ' and '.join(str(r) for r in self.rules)
|
||||
|
||||
def __call__(self, target, cred):
|
||||
"""
|
||||
Check the policy. Requires that all rules accept in order to
|
||||
return True.
|
||||
"""
|
||||
|
||||
for rule in self.rules:
|
||||
if not rule(target, cred):
|
||||
return False
|
||||
|
||||
return True
|
||||
|
||||
def add_check(self, rule):
|
||||
"""
|
||||
Allows addition of another rule to the list of rules that will
|
||||
be tested. Returns the AndCheck object for convenience.
|
||||
"""
|
||||
|
||||
self.rules.append(rule)
|
||||
return self
|
||||
|
||||
|
||||
class OrCheck(BaseCheck):
|
||||
"""
|
||||
A policy check that requires that at least one of a list of other
|
||||
checks returns True. Implements the "or" operator.
|
||||
"""
|
||||
|
||||
def __init__(self, rules):
|
||||
"""
|
||||
Initialize the 'or' check.
|
||||
|
||||
:param rules: A list of rules that will be tested.
|
||||
"""
|
||||
|
||||
self.rules = rules
|
||||
|
||||
def __str__(self):
|
||||
"""Return a string representation of this check."""
|
||||
|
||||
return "(%s)" % ' or '.join(str(r) for r in self.rules)
|
||||
|
||||
def __call__(self, target, cred):
|
||||
"""
|
||||
Check the policy. Requires that at least one rule accept in
|
||||
order to return True.
|
||||
"""
|
||||
|
||||
for rule in self.rules:
|
||||
if rule(target, cred):
|
||||
return True
|
||||
|
||||
return False
|
||||
|
||||
def add_check(self, rule):
|
||||
"""
|
||||
Allows addition of another rule to the list of rules that will
|
||||
be tested. Returns the OrCheck object for convenience.
|
||||
"""
|
||||
|
||||
self.rules.append(rule)
|
||||
return self
|
||||
|
||||
|
||||
def _parse_check(rule):
|
||||
"""
|
||||
Parse a single base check rule into an appropriate Check object.
|
||||
"""
|
||||
|
||||
# Handle the special checks
|
||||
if rule == '!':
|
||||
return FalseCheck()
|
||||
elif rule == '@':
|
||||
return TrueCheck()
|
||||
|
||||
try:
|
||||
kind, match = rule.split(':', 1)
|
||||
except Exception:
|
||||
LOG.exception(_("Failed to understand rule %(rule)s") % locals())
|
||||
# If the rule is invalid, we'll fail closed
|
||||
return FalseCheck()
|
||||
|
||||
# Find what implements the check
|
||||
if kind in _checks:
|
||||
return _checks[kind](kind, match)
|
||||
elif None in _checks:
|
||||
return _checks[None](kind, match)
|
||||
else:
|
||||
LOG.error(_("No handler for matches of kind %s") % kind)
|
||||
return FalseCheck()
|
||||
|
||||
|
||||
def _parse_list_rule(rule):
|
||||
"""
|
||||
Provided for backwards compatibility. Translates the old
|
||||
list-of-lists syntax into a tree of Check objects.
|
||||
"""
|
||||
|
||||
# Empty rule defaults to True
|
||||
if not rule:
|
||||
return TrueCheck()
|
||||
|
||||
# Outer list is joined by "or"; inner list by "and"
|
||||
or_list = []
|
||||
for inner_rule in rule:
|
||||
# Elide empty inner lists
|
||||
if not inner_rule:
|
||||
continue
|
||||
|
||||
# Handle bare strings
|
||||
if isinstance(inner_rule, basestring):
|
||||
inner_rule = [inner_rule]
|
||||
|
||||
# Parse the inner rules into Check objects
|
||||
and_list = [_parse_check(r) for r in inner_rule]
|
||||
|
||||
# Append the appropriate check to the or_list
|
||||
if len(and_list) == 1:
|
||||
or_list.append(and_list[0])
|
||||
else:
|
||||
or_list.append(AndCheck(and_list))
|
||||
|
||||
# If we have only one check, omit the "or"
|
||||
if len(or_list) == 0:
|
||||
return FalseCheck()
|
||||
elif len(or_list) == 1:
|
||||
return or_list[0]
|
||||
|
||||
return OrCheck(or_list)
|
||||
|
||||
|
||||
# Used for tokenizing the policy language
|
||||
_tokenize_re = re.compile(r'\s+')
|
||||
|
||||
|
||||
def _parse_tokenize(rule):
|
||||
"""
|
||||
Tokenizer for the policy language.
|
||||
|
||||
Most of the single-character tokens are specified in the
|
||||
_tokenize_re; however, parentheses need to be handled specially,
|
||||
because they can appear inside a check string. Thankfully, those
|
||||
parentheses that appear inside a check string can never occur at
|
||||
the very beginning or end ("%(variable)s" is the correct syntax).
|
||||
"""
|
||||
|
||||
for tok in _tokenize_re.split(rule):
|
||||
# Skip empty tokens
|
||||
if not tok or tok.isspace():
|
||||
continue
|
||||
|
||||
# Handle leading parens on the token
|
||||
clean = tok.lstrip('(')
|
||||
for i in range(len(tok) - len(clean)):
|
||||
yield '(', '('
|
||||
|
||||
# If it was only parentheses, continue
|
||||
if not clean:
|
||||
continue
|
||||
else:
|
||||
tok = clean
|
||||
|
||||
# Handle trailing parens on the token
|
||||
clean = tok.rstrip(')')
|
||||
trail = len(tok) - len(clean)
|
||||
|
||||
# Yield the cleaned token
|
||||
lowered = clean.lower()
|
||||
if lowered in ('and', 'or', 'not'):
|
||||
# Special tokens
|
||||
yield lowered, clean
|
||||
elif clean:
|
||||
# Not a special token, but not composed solely of ')'
|
||||
if len(tok) >= 2 and ((tok[0], tok[-1]) in
|
||||
[('"', '"'), ("'", "'")]):
|
||||
# It's a quoted string
|
||||
yield 'string', tok[1:-1]
|
||||
else:
|
||||
yield 'check', _parse_check(clean)
|
||||
|
||||
# Yield the trailing parens
|
||||
for i in range(trail):
|
||||
yield ')', ')'
|
||||
|
||||
|
||||
class ParseStateMeta(type):
|
||||
"""
|
||||
Metaclass for the ParseState class. Facilitates identifying
|
||||
reduction methods.
|
||||
"""
|
||||
|
||||
def __new__(mcs, name, bases, cls_dict):
|
||||
"""
|
||||
Create the class. Injects the 'reducers' list, a list of
|
||||
tuples matching token sequences to the names of the
|
||||
corresponding reduction methods.
|
||||
"""
|
||||
|
||||
reducers = []
|
||||
|
||||
for key, value in cls_dict.items():
|
||||
if not hasattr(value, 'reducers'):
|
||||
continue
|
||||
for reduction in value.reducers:
|
||||
reducers.append((reduction, key))
|
||||
|
||||
cls_dict['reducers'] = reducers
|
||||
|
||||
return super(ParseStateMeta, mcs).__new__(mcs, name, bases, cls_dict)
|
||||
|
||||
|
||||
def reducer(*tokens):
|
||||
"""
|
||||
Decorator for reduction methods. Arguments are a sequence of
|
||||
tokens, in order, which should trigger running this reduction
|
||||
method.
|
||||
"""
|
||||
|
||||
def decorator(func):
|
||||
# Make sure we have a list of reducer sequences
|
||||
if not hasattr(func, 'reducers'):
|
||||
func.reducers = []
|
||||
|
||||
# Add the tokens to the list of reducer sequences
|
||||
func.reducers.append(list(tokens))
|
||||
|
||||
return func
|
||||
|
||||
return decorator
|
||||
|
||||
|
||||
class ParseState(object):
|
||||
"""
|
||||
Implement the core of parsing the policy language. Uses a greedy
|
||||
reduction algorithm to reduce a sequence of tokens into a single
|
||||
terminal, the value of which will be the root of the Check tree.
|
||||
|
||||
Note: error reporting is rather lacking. The best we can get with
|
||||
this parser formulation is an overall "parse failed" error.
|
||||
Fortunately, the policy language is simple enough that this
|
||||
shouldn't be that big a problem.
|
||||
"""
|
||||
|
||||
__metaclass__ = ParseStateMeta
|
||||
|
||||
def __init__(self):
|
||||
"""Initialize the ParseState."""
|
||||
|
||||
self.tokens = []
|
||||
self.values = []
|
||||
|
||||
def reduce(self):
|
||||
"""
|
||||
Perform a greedy reduction of the token stream. If a reducer
|
||||
method matches, it will be executed, then the reduce() method
|
||||
will be called recursively to search for any more possible
|
||||
reductions.
|
||||
"""
|
||||
|
||||
for reduction, methname in self.reducers:
|
||||
if (len(self.tokens) >= len(reduction) and
|
||||
self.tokens[-len(reduction):] == reduction):
|
||||
# Get the reduction method
|
||||
meth = getattr(self, methname)
|
||||
|
||||
# Reduce the token stream
|
||||
results = meth(*self.values[-len(reduction):])
|
||||
|
||||
# Update the tokens and values
|
||||
self.tokens[-len(reduction):] = [r[0] for r in results]
|
||||
self.values[-len(reduction):] = [r[1] for r in results]
|
||||
|
||||
# Check for any more reductions
|
||||
return self.reduce()
|
||||
|
||||
def shift(self, tok, value):
|
||||
"""Adds one more token to the state. Calls reduce()."""
|
||||
|
||||
self.tokens.append(tok)
|
||||
self.values.append(value)
|
||||
|
||||
# Do a greedy reduce...
|
||||
self.reduce()
|
||||
|
||||
@property
|
||||
def result(self):
|
||||
"""
|
||||
Obtain the final result of the parse. Raises ValueError if
|
||||
the parse failed to reduce to a single result.
|
||||
"""
|
||||
|
||||
if len(self.values) != 1:
|
||||
raise ValueError("Could not parse rule")
|
||||
return self.values[0]
|
||||
|
||||
@reducer('(', 'check', ')')
|
||||
@reducer('(', 'and_expr', ')')
|
||||
@reducer('(', 'or_expr', ')')
|
||||
def _wrap_check(self, _p1, check, _p2):
|
||||
"""Turn parenthesized expressions into a 'check' token."""
|
||||
|
||||
return [('check', check)]
|
||||
|
||||
@reducer('check', 'and', 'check')
|
||||
def _make_and_expr(self, check1, _and, check2):
|
||||
"""
|
||||
Create an 'and_expr' from two checks joined by the 'and'
|
||||
operator.
|
||||
"""
|
||||
|
||||
return [('and_expr', AndCheck([check1, check2]))]
|
||||
|
||||
@reducer('and_expr', 'and', 'check')
|
||||
def _extend_and_expr(self, and_expr, _and, check):
|
||||
"""
|
||||
Extend an 'and_expr' by adding one more check.
|
||||
"""
|
||||
|
||||
return [('and_expr', and_expr.add_check(check))]
|
||||
|
||||
@reducer('check', 'or', 'check')
|
||||
def _make_or_expr(self, check1, _or, check2):
|
||||
"""
|
||||
Create an 'or_expr' from two checks joined by the 'or'
|
||||
operator.
|
||||
"""
|
||||
|
||||
return [('or_expr', OrCheck([check1, check2]))]
|
||||
|
||||
@reducer('or_expr', 'or', 'check')
|
||||
def _extend_or_expr(self, or_expr, _or, check):
|
||||
"""
|
||||
Extend an 'or_expr' by adding one more check.
|
||||
"""
|
||||
|
||||
return [('or_expr', or_expr.add_check(check))]
|
||||
|
||||
@reducer('not', 'check')
|
||||
def _make_not_expr(self, _not, check):
|
||||
"""Invert the result of another check."""
|
||||
|
||||
return [('check', NotCheck(check))]
|
||||
|
||||
|
||||
def _parse_text_rule(rule):
|
||||
"""
|
||||
Translates a policy written in the policy language into a tree of
|
||||
Check objects.
|
||||
"""
|
||||
|
||||
# Empty rule means always accept
|
||||
if not rule:
|
||||
return TrueCheck()
|
||||
|
||||
# Parse the token stream
|
||||
state = ParseState()
|
||||
for tok, value in _parse_tokenize(rule):
|
||||
state.shift(tok, value)
|
||||
|
||||
try:
|
||||
return state.result
|
||||
except ValueError:
|
||||
# Couldn't parse the rule
|
||||
LOG.exception(_("Failed to understand rule %(rule)r") % locals())
|
||||
|
||||
# Fail closed
|
||||
return FalseCheck()
|
||||
|
||||
|
||||
def parse_rule(rule):
|
||||
"""
|
||||
Parses a policy rule into a tree of Check objects.
|
||||
"""
|
||||
|
||||
# If the rule is a string, it's in the policy language
|
||||
if isinstance(rule, basestring):
|
||||
return _parse_text_rule(rule)
|
||||
return _parse_list_rule(rule)
|
||||
|
||||
|
||||
def register(name, func=None):
|
||||
"""
|
||||
Register a function as a policy check.
|
||||
Register a function or Check class as a policy check.
|
||||
|
||||
:param name: Gives the name of the check type, e.g., 'rule',
|
||||
'role', etc. If name is None, a default function
|
||||
'role', etc. If name is None, a default check type
|
||||
will be registered.
|
||||
:param func: If given, provides the function to register. If not
|
||||
given, returns a function taking one argument to
|
||||
specify the function to register, allowing use as a
|
||||
decorator.
|
||||
:param func: If given, provides the function or class to register.
|
||||
If not given, returns a function taking one argument
|
||||
to specify the function or class to register,
|
||||
allowing use as a decorator.
|
||||
"""
|
||||
|
||||
# Perform the actual decoration by registering the function.
|
||||
# Returns the function for compliance with the decorator
|
||||
# interface.
|
||||
# Perform the actual decoration by registering the function or
|
||||
# class. Returns the function or class for compliance with the
|
||||
# decorator interface.
|
||||
def decorator(func):
|
||||
# Register the function
|
||||
Brain._register(name, func)
|
||||
_checks[name] = func
|
||||
return func
|
||||
|
||||
# If the function is given, do the registration
|
||||
# If the function or class is given, do the registration
|
||||
if func:
|
||||
return decorator(func)
|
||||
|
||||
@ -246,55 +721,59 @@ def register(name, func=None):
|
||||
|
||||
|
||||
@register("rule")
|
||||
def _check_rule(brain, match_kind, match, target_dict, cred_dict):
|
||||
"""Recursively checks credentials based on the brains rules."""
|
||||
try:
|
||||
new_match_list = brain.rules[match]
|
||||
except KeyError:
|
||||
if brain.default_rule and match != brain.default_rule:
|
||||
new_match_list = ('rule:%s' % brain.default_rule,)
|
||||
else:
|
||||
return False
|
||||
class RuleCheck(Check):
|
||||
def __call__(self, target, creds):
|
||||
"""
|
||||
Recursively checks credentials based on the defined rules.
|
||||
"""
|
||||
|
||||
return brain.check(new_match_list, target_dict, cred_dict)
|
||||
try:
|
||||
return _rules[self.match](target, creds)
|
||||
except KeyError:
|
||||
# We don't have any matching rule; fail closed
|
||||
return False
|
||||
|
||||
|
||||
@register("role")
|
||||
def _check_role(brain, match_kind, match, target_dict, cred_dict):
|
||||
"""Check that there is a matching role in the cred dict."""
|
||||
return match.lower() in [x.lower() for x in cred_dict['roles']]
|
||||
class RoleCheck(Check):
|
||||
def __call__(self, target, creds):
|
||||
"""Check that there is a matching role in the cred dict."""
|
||||
|
||||
return self.match.lower() in [x.lower() for x in creds['roles']]
|
||||
|
||||
|
||||
@register('http')
|
||||
def _check_http(brain, match_kind, match, target_dict, cred_dict):
|
||||
"""Check http: rules by calling to a remote server.
|
||||
class HttpCheck(Check):
|
||||
def __call__(self, target, creds):
|
||||
"""
|
||||
Check http: rules by calling to a remote server.
|
||||
|
||||
This example implementation simply verifies that the response is
|
||||
exactly 'True'. A custom brain using response codes could easily
|
||||
be implemented.
|
||||
This example implementation simply verifies that the response
|
||||
is exactly 'True'.
|
||||
"""
|
||||
|
||||
"""
|
||||
url = 'http:' + (match % target_dict)
|
||||
data = {'target': jsonutils.dumps(target_dict),
|
||||
'credentials': jsonutils.dumps(cred_dict)}
|
||||
post_data = urllib.urlencode(data)
|
||||
f = urllib2.urlopen(url, post_data)
|
||||
return f.read() == "True"
|
||||
url = ('http:' + self.match) % target
|
||||
data = {'target': jsonutils.dumps(target),
|
||||
'credentials': jsonutils.dumps(creds)}
|
||||
post_data = urllib.urlencode(data)
|
||||
f = urllib2.urlopen(url, post_data)
|
||||
return f.read() == "True"
|
||||
|
||||
|
||||
@register(None)
|
||||
def _check_generic(brain, match_kind, match, target_dict, cred_dict):
|
||||
"""Check an individual match.
|
||||
class GenericCheck(Check):
|
||||
def __call__(self, target, creds):
|
||||
"""
|
||||
Check an individual match.
|
||||
|
||||
Matches look like:
|
||||
Matches look like:
|
||||
|
||||
tenant:%(tenant_id)s
|
||||
role:compute:admin
|
||||
tenant:%(tenant_id)s
|
||||
role:compute:admin
|
||||
"""
|
||||
|
||||
"""
|
||||
|
||||
# TODO(termie): do dict inspection via dot syntax
|
||||
match = match % target_dict
|
||||
if match_kind in cred_dict:
|
||||
return match == unicode(cred_dict[match_kind])
|
||||
return False
|
||||
# TODO(termie): do dict inspection via dot syntax
|
||||
match = self.match % target
|
||||
if self.kind in creds:
|
||||
return match == unicode(creds[self.kind])
|
||||
return False
|
||||
|
@ -1,3 +1,3 @@
|
||||
{
|
||||
"default": []
|
||||
"default": ""
|
||||
}
|
||||
|
@ -305,7 +305,7 @@ class BaseCacheManageMiddlewareTest(object):
|
||||
self.assertEqual(image_id1, cached_images[0]['image_id'])
|
||||
|
||||
# Set policy to disallow access to cache management
|
||||
rules = {"manage_image_cache": [["false:false"]]}
|
||||
rules = {"manage_image_cache": '!'}
|
||||
self.set_policy_rules(rules)
|
||||
|
||||
# Verify an unprivileged user cannot see cached images
|
||||
|
@ -30,7 +30,7 @@ class TestPolicyEnforcer(base.IsolatedUnitTest):
|
||||
enforcer.enforce(context, 'get_image', {})
|
||||
|
||||
def test_policy_file_custom_rules_default_location(self):
|
||||
rules = {"get_image": [["false:false"]]}
|
||||
rules = {"get_image": '!'}
|
||||
self.set_policy_rules(rules)
|
||||
|
||||
enforcer = glance.api.policy.Enforcer()
|
||||
@ -42,7 +42,7 @@ class TestPolicyEnforcer(base.IsolatedUnitTest):
|
||||
def test_policy_file_custom_location(self):
|
||||
self.config(policy_file=os.path.join(self.test_dir, 'gobble.gobble'))
|
||||
|
||||
rules = {"get_image": [["false:false"]]}
|
||||
rules = {"get_image": '!'}
|
||||
self.set_policy_rules(rules)
|
||||
|
||||
enforcer = glance.api.policy.Enforcer()
|
||||
@ -51,6 +51,17 @@ class TestPolicyEnforcer(base.IsolatedUnitTest):
|
||||
self.assertRaises(exception.Forbidden,
|
||||
enforcer.enforce, context, 'get_image', {})
|
||||
|
||||
def test_policy_file_check(self):
|
||||
self.config(policy_file=os.path.join(self.test_dir, 'gobble.gobble'))
|
||||
|
||||
rules = {"get_image": '!'}
|
||||
self.set_policy_rules(rules)
|
||||
|
||||
enforcer = glance.api.policy.Enforcer()
|
||||
|
||||
context = glance.context.RequestContext(roles=[])
|
||||
self.assertEqual(enforcer.check(context, 'get_image', {}), False)
|
||||
|
||||
|
||||
class TestPolicyEnforcerNoFile(test_utils.BaseTestCase):
|
||||
def test_policy_file_specified_but_not_found(self):
|
||||
|
@ -2238,7 +2238,7 @@ class TestGlanceAPI(base.IsolatedUnitTest):
|
||||
self.assertEquals(res.status_int, httplib.BAD_REQUEST)
|
||||
|
||||
def test_add_image_unauthorized(self):
|
||||
rules = {"add_image": [["false:false"]]}
|
||||
rules = {"add_image": '!'}
|
||||
self.set_policy_rules(rules)
|
||||
fixture_headers = {'x-image-meta-store': 'file',
|
||||
'x-image-meta-disk-format': 'vhd',
|
||||
@ -2256,7 +2256,7 @@ class TestGlanceAPI(base.IsolatedUnitTest):
|
||||
self.assertEquals(res.status_int, 403)
|
||||
|
||||
def test_add_public_image_unauthorized(self):
|
||||
rules = {"add_image": [], "publicize_image": [["false:false"]]}
|
||||
rules = {"add_image": '@', "publicize_image": '!'}
|
||||
self.set_policy_rules(rules)
|
||||
fixture_headers = {'x-image-meta-store': 'file',
|
||||
'x-image-meta-is-public': 'true',
|
||||
@ -2502,7 +2502,7 @@ class TestGlanceAPI(base.IsolatedUnitTest):
|
||||
|
||||
def test_publicize_image_unauthorized(self):
|
||||
"""Create a non-public image then fail to make public"""
|
||||
rules = {"add_image": [], "publicize_image": [["false:false"]]}
|
||||
rules = {"add_image": '@', "publicize_image": '!'}
|
||||
self.set_policy_rules(rules)
|
||||
|
||||
fixture_headers = {'x-image-meta-store': 'file',
|
||||
@ -2731,14 +2731,14 @@ class TestGlanceAPI(base.IsolatedUnitTest):
|
||||
self.assertEquals(res.status_int, 400)
|
||||
|
||||
def test_get_images_detailed_unauthorized(self):
|
||||
rules = {"get_images": [["false:false"]]}
|
||||
rules = {"get_images": '!'}
|
||||
self.set_policy_rules(rules)
|
||||
req = webob.Request.blank('/images/detail')
|
||||
res = req.get_response(self.api)
|
||||
self.assertEquals(res.status_int, 403)
|
||||
|
||||
def test_get_images_unauthorized(self):
|
||||
rules = {"get_images": [["false:false"]]}
|
||||
rules = {"get_images": '!'}
|
||||
self.set_policy_rules(rules)
|
||||
req = webob.Request.blank('/images/detail')
|
||||
res = req.get_response(self.api)
|
||||
@ -2899,7 +2899,7 @@ class TestGlanceAPI(base.IsolatedUnitTest):
|
||||
self.assertEquals(value, res.headers[key])
|
||||
|
||||
def test_image_meta_unauthorized(self):
|
||||
rules = {"get_image": [["false:false"]]}
|
||||
rules = {"get_image": '!'}
|
||||
self.set_policy_rules(rules)
|
||||
req = webob.Request.blank("/images/%s" % UUID2)
|
||||
req.method = 'HEAD'
|
||||
@ -2919,14 +2919,14 @@ class TestGlanceAPI(base.IsolatedUnitTest):
|
||||
self.assertEquals(res.status_int, webob.exc.HTTPNotFound.code)
|
||||
|
||||
def test_show_image_unauthorized(self):
|
||||
rules = {"get_image": [["false:false"]]}
|
||||
rules = {"get_image": '!'}
|
||||
self.set_policy_rules(rules)
|
||||
req = webob.Request.blank("/images/%s" % UUID2)
|
||||
res = req.get_response(self.api)
|
||||
self.assertEqual(res.status_int, 403)
|
||||
|
||||
def test_show_image_unauthorized_download(self):
|
||||
rules = {"download_image": [["false:false"]]}
|
||||
rules = {"download_image": '!'}
|
||||
self.set_policy_rules(rules)
|
||||
req = webob.Request.blank("/images/%s" % UUID2)
|
||||
res = req.get_response(self.api)
|
||||
@ -3054,7 +3054,7 @@ class TestGlanceAPI(base.IsolatedUnitTest):
|
||||
self.assertEquals(res.status_int, httplib.FORBIDDEN)
|
||||
|
||||
def test_delete_image_unauthorized(self):
|
||||
rules = {"delete_image": [["false:false"]]}
|
||||
rules = {"delete_image": '!'}
|
||||
self.set_policy_rules(rules)
|
||||
req = webob.Request.blank("/images/%s" % UUID2)
|
||||
req.method = 'DELETE'
|
||||
|
Loading…
Reference in New Issue
Block a user