python-zope.securitypolicy 3.7.0-0ubuntu4 / usr / share / pyshared / zope.securitypolicy-3.7.0.egg-info / PKG-INFO

Metadata-Version: 1.1
Name: zope.securitypolicy
Version: 3.7.0
Summary: Default security policy for Zope3
Home-page: http://pypi.python.org/pypi/zope.securitypolicy
Author: Zope Foundation and Contributors
Author-email: zope-dev@zope.org
License: ZPL 2.1
Description: This package provides an useful security policy for Zope3. It's the
        default security policy used in "zope3 the application" and many other
        zope-based projects.
        
        .. contents::
        
        ============================
        Classic Zope Security Policy
        ============================
        
        This package implements a role-based security policy similar to the
        policy found in Zope 2.  The security policy is responsible for
        deciding whether an interaction has a permission on an object.  This
        security policy does this using grant and denial information.  Managers
        can grant or deny:
        
          - roles to principals,
        
          - permissions to principals, and
        
          - permissions to roles
        
        Grants and denials are stored as annotations on objects.  To store
        grants and denials, objects must be annotatable:
        
          >>> import zope.interface
          >>> from zope.annotation.interfaces import IAttributeAnnotatable
          >>> class Ob:
          ...     zope.interface.implements(IAttributeAnnotatable)
        
          >>> ob = Ob()
        
        We use objects to represent principals.  These objects implement an
        interface named `IPrincipal`, but the security policy only uses the `id`
        and `groups` attributes:
        
          >>> class Principal:
          ...     def __init__(self, id):
          ...         self.id = id
          ...         self.groups = []
        
          >>> principal = Principal('bob')
        
        Roles and permissions are also represented by objects, however, for
        the purposes of the security policy, only string `ids` are used.
        
        The security policy provides a factory for creating interactions:
        
          >>> import zope.securitypolicy.zopepolicy
          >>> interaction = zope.securitypolicy.zopepolicy.ZopeSecurityPolicy()
        
        An interaction represents a specific interaction between some
        principals (normally users) and the system.  Normally, we are only
        concerned with the interaction of one principal with the system, although
        we can have interactions of multiple principals.  Multiple-principal
        interactions normally occur when untrusted users store code on a
        system for later execution.  When untrusted code is executing, the
        authors of the code participate in the interaction.  An
        interaction has a permission on an object only if all of the
        principals participating in the interaction have access to the object.
        
        The `checkPermission` method on interactions is used to test whether
        an interaction has a permission for an object.  An interaction without
        participants always has every permission:
        
          >>> interaction.checkPermission('P1', ob)
          True
        
        In this example, 'P1' is a permission id.
        
        Normally, interactions have participants:
        
          >>> class Participation:
          ...     interaction = None
          >>> participation = Participation()
          >>> participation.principal = principal
          >>> interaction.add(participation)
        
        If we have participants, then we don't have a permission unless there
        are grants:
        
          >>> interaction.checkPermission('P1', ob)
          False
        
        Note, however, that we always have the CheckerPublic permission:
        
          >>> from zope.security.checker import CheckerPublic
          >>> interaction.checkPermission(CheckerPublic, ob)
          True
        
        We make grants and denials on objects by adapting them to various
        granting interfaces.  The objects returned from the adaptation are 
        object-specific manager objects:
        
          >>> from zope.securitypolicy import interfaces
          >>> roleper  = interfaces.IRolePermissionManager(ob)
          >>> prinrole = interfaces.IPrincipalRoleManager(ob)
          >>> prinper  = interfaces.IPrincipalPermissionManager(ob)
        
        The computations involved in checking permissions can be
        significant. To reduce the computational cost, caching is used
        extensively. We could invalidate the cache as we make grants, but the
        adapters for making grants will automatically invalidate the cache of
        the current interaction.  They use the security-management apis to do
        this. To take advantage of the cache invalidation, we'll need to let
        the security-management system manage our interactions.  First, we'll
        set our security policy as the default:
        
          >>> import zope.security.management
          >>> oldpolicy = zope.security.management.setSecurityPolicy(
          ...      zope.securitypolicy.zopepolicy.ZopeSecurityPolicy)
        
        and then we'll create a new interaction:
        
          >>> participation = Participation()
          >>> participation.principal = principal
          >>> zope.security.management.newInteraction(participation)
          >>> interaction = zope.security.management.getInteraction()
        
        We normally provide access by granting permissions to roles for an object:
        
          >>> roleper.grantPermissionToRole('P1', 'R1')
        
        and then granting roles to principals for an object (local roles):
        
          >>> prinrole.assignRoleToPrincipal('R1', 'bob')
        
        The combination of these grants, which we call a role-based grant,
        provides the permission:
        
          >>> interaction.checkPermission('P1', ob)
          True
        
        We can also provide a permission directly:
        
          >>> prinper.grantPermissionToPrincipal('P2', 'bob')
          >>> interaction.checkPermission('P2', ob)
          True
        
        Permission grants or denials override role-based grant or denials.  So
        if we deny P1:
        
          >>> prinper.denyPermissionToPrincipal('P1', 'bob')
        
        we cause the interaction to lack the permission, despite the role
        grants:
        
          >>> interaction.checkPermission('P1', ob)
          False
        
        Similarly, even if we have a role-based denial of P2:
        
          >>> roleper.denyPermissionToRole('P2', 'R1')
        
        we still have access, because of the permission-based grant:
        
          >>> interaction.checkPermission('P2', ob)
          True
        
        A role-based denial doesn't actually deny a permission; rather it
        prevents the granting of a permission. So, if we have both grants and
        denials based on roles, we have access:
        
          >>> roleper.grantPermissionToRole('P3', 'R1')
          >>> roleper.grantPermissionToRole('P3', 'R2')
          >>> roleper.denyPermissionToRole('P3', 'R3')
          >>> prinrole.removeRoleFromPrincipal('R2', 'bob')
          >>> prinrole.assignRoleToPrincipal('R3', 'bob')
        
          >>> interaction.checkPermission('P3', ob)
          True
        
        Global grants
        -------------
        
        Grants made to an object are said to be "local".  We can also make
        global grants:
        
          >>> from zope.securitypolicy.rolepermission import \
          ...     rolePermissionManager as roleperG
          >>> from zope.securitypolicy.principalpermission import \
          ...     principalPermissionManager as prinperG
          >>> from zope.securitypolicy.principalrole import \
          ...     principalRoleManager as prinroleG
        
        And the same rules apply to global grants and denials.
        
          >>> roleperG.grantPermissionToRole('P1G', 'R1G', False)
        
        In these tests, we aren't bothering to define any roles, permissions,
        or principals, so we pass an extra argument that tells the granting
        routines not to check the validity of the values.
        
          >>> prinroleG.assignRoleToPrincipal('R1G', 'bob', False)
          >>> interaction.checkPermission('P1G', ob)
          True
        
          >>> prinperG.grantPermissionToPrincipal('P2G', 'bob', False)
          >>> interaction.checkPermission('P2G', ob)
          True
        
          >>> prinperG.denyPermissionToPrincipal('P1G', 'bob', False)
          >>> interaction.checkPermission('P1G', ob)
          False
        
          >>> roleperG.denyPermissionToRole('P2G', 'R1G', False)
          >>> interaction.checkPermission('P2G', ob)
          True
        
          >>> roleperG.grantPermissionToRole('P3G', 'R1G', False)
          >>> roleperG.grantPermissionToRole('P3G', 'R2G', False)
          >>> roleperG.denyPermissionToRole('P3G', 'R3G', False)
          >>> prinroleG.removeRoleFromPrincipal('R2G', 'bob', False)
          >>> prinroleG.assignRoleToPrincipal('R3G', 'bob', False)
          >>> interaction.checkPermission('P3G', ob)
          True
        
        Local versus global grants
        --------------------------
        
        We, of course, acquire global grants by default:
        
          >>> interaction.checkPermission('P1G', ob)
          False
          >>> interaction.checkPermission('P2G', ob)
          True
          >>> interaction.checkPermission('P3G', ob)
          True
        
        Local role-based grants do not override global principal-specific denials:
        
          >>> roleper.grantPermissionToRole('P1G', 'R1G')
          >>> prinrole.assignRoleToPrincipal('R1G', 'bob')
          >>> interaction.checkPermission('P1G', ob)
          False
        
        And local role-based denials don't override global
        principal-grants:
        
          >>> roleper.denyPermissionToRole('P2G', 'R1G')
          >>> interaction.checkPermission('P2G', ob)
          True
        
        A local role-based deny can cancel a global role-based grant:
        
          >>> roleper.denyPermissionToRole('P3G', 'R1G')
          >>> interaction.checkPermission('P3G', ob)
          False
        
        and a local role-based grant can override a global role-based denial:
        
          >>> roleperG.denyPermissionToRole('P4G', 'R1G', False)
          >>> prinroleG.assignRoleToPrincipal('R1G', "bob", False)
          >>> interaction.checkPermission('P4G', ob)
          False
          >>> roleper.grantPermissionToRole('P4G', 'R1G')
          >>> interaction.checkPermission('P4G', ob)
          True
          >>> prinroleG.removeRoleFromPrincipal('R1G', "bob", False)
          >>> interaction.checkPermission('P4G', ob)
          True
        
        Of course, a local permission-based grant or denial overrides any
        global setting and overrides local role-based grants or denials:
        
          >>> prinper.grantPermissionToPrincipal('P3G', 'bob')
          >>> interaction.checkPermission('P3G', ob)
          True
        
          >>> prinper.denyPermissionToPrincipal('P2G', 'bob')
          >>> interaction.checkPermission('P2G', ob)
          False
        
        Sublocations
        ------------
        
        We can have sub-locations. A sublocation of a location is an object
        whose `__parent__` attribute is the location:
        
          >>> ob2 = Ob()
          >>> ob2.__parent__ = ob
        
        By default, sublocations acquire grants from higher locations:
        
          >>> interaction.checkPermission('P1', ob2)
          False
          >>> interaction.checkPermission('P2', ob2)
          True
          >>> interaction.checkPermission('P3', ob2)
          True
          >>> interaction.checkPermission('P1G', ob2)
          False
          >>> interaction.checkPermission('P2G', ob2)
          False
          >>> interaction.checkPermission('P3G', ob2)
          True
          >>> interaction.checkPermission('P4G', ob2)
          True
        
        Sublocation role-based grants do not override their parent
        principal-specific denials:
        
          >>> roleper2  = interfaces.IRolePermissionManager(ob2)
          >>> prinrole2 = interfaces.IPrincipalRoleManager(ob2)
          >>> prinper2  = interfaces.IPrincipalPermissionManager(ob2)
        
          >>> roleper2.grantPermissionToRole('P1', 'R1')
          >>> prinrole2.assignRoleToPrincipal('R1', 'bob')
          >>> interaction.checkPermission('P1', ob2)
          False
        
        And local role-based denials don't override their parents
        principal-grant:
        
          >>> roleper2.denyPermissionToRole('P2', 'R1')
          >>> interaction.checkPermission('P2', ob2)
          True
        
        A local role-based deny can cancel a parent role-based grant:
        
          >>> roleper2.denyPermissionToRole('P3', 'R1')
          >>> interaction.checkPermission('P3', ob2)
          False
        
        and a local role-based grant can override a parent role-based denial:
        
          >>> roleper.denyPermissionToRole('P4', 'R1')
          >>> prinrole.assignRoleToPrincipal('R1', 'bob')
          >>> interaction.checkPermission('P4', ob2)
          False
          >>> roleper2.grantPermissionToRole('P4', 'R1')
          >>> interaction.checkPermission('P4', ob2)
          True
          >>> prinrole.removeRoleFromPrincipal('R1', 'bob')
          >>> interaction.checkPermission('P4', ob2)
          True
        
        
        Of course, a local permission-based grant or denial overrides any
        global setting and overrides local role-based grants or denials:
        
          >>> prinper.grantPermissionToPrincipal('P3', 'bob')
          >>> interaction.checkPermission('P3', ob2)
          True
        
          >>> prinper.denyPermissionToPrincipal('P2', 'bob')
          >>> interaction.checkPermission('P2', ob2)
          False
        
        If an object is not annotatable, but does have a parent, it will get
        its grants from its parent:
        
          >>> class C:
          ...     pass
        
          >>> ob3 = C()
          >>> ob3.__parent__ = ob
        
          >>> interaction.checkPermission('P1', ob3)
          False
          >>> interaction.checkPermission('P2', ob3)
          False
          >>> interaction.checkPermission('P3', ob3)
          True
          >>> interaction.checkPermission('P1G', ob3)
          False
          >>> interaction.checkPermission('P2G', ob3)
          False
          >>> interaction.checkPermission('P3G', ob3)
          True
          >>> interaction.checkPermission('P4G', ob3)
          True
        
        The same results will be had if there are multiple non-annotatable
        objects:
        
          >>> ob3.__parent__ = C()
          >>> ob3.__parent__.__parent__ = ob
        
          >>> interaction.checkPermission('P1', ob3)
          False
          >>> interaction.checkPermission('P2', ob3)
          False
          >>> interaction.checkPermission('P3', ob3)
          True
          >>> interaction.checkPermission('P1G', ob3)
          False
          >>> interaction.checkPermission('P2G', ob3)
          False
          >>> interaction.checkPermission('P3G', ob3)
          True
          >>> interaction.checkPermission('P4G', ob3)
          True
        
        and if an object doesn't have a parent:
        
          >>> ob4 = C()
        
        it will have whatever grants were made globally:
        
          >>> interaction.checkPermission('P1', ob4)
          False
          >>> interaction.checkPermission('P2', ob4)
          False
          >>> interaction.checkPermission('P3', ob4)
          False
          >>> interaction.checkPermission('P1G', ob4)
          False
          >>> interaction.checkPermission('P2G', ob4)
          True
          >>> interaction.checkPermission('P3G', ob4)
          False
          >>> interaction.checkPermission('P4G', ob4)
          False
        
          >>> prinroleG.assignRoleToPrincipal('R1G', "bob", False)
          >>> interaction.checkPermission('P3G', ob4)
          True
        
        We'll get the same result if we have a non-annotatable parent without a
        parent:
        
          >>> ob3.__parent__ = C()
        
          >>> interaction.checkPermission('P1', ob3)
          False
          >>> interaction.checkPermission('P2', ob3)
          False
          >>> interaction.checkPermission('P3', ob3)
          False
          >>> interaction.checkPermission('P1G', ob3)
          False
          >>> interaction.checkPermission('P2G', ob3)
          True
          >>> interaction.checkPermission('P3G', ob3)
          True
          >>> interaction.checkPermission('P4G', ob3)
          False
        
        The Anonymous role
        ------------------
        
        The security policy defines a special role named "zope.Anonymous".  All
        principals have this role and the role cannot be taken away.
        
          >>> roleperG.grantPermissionToRole('P5', 'zope.Anonymous', False)
          >>> interaction.checkPermission('P5', ob2)
          True
        
        Proxies
        -------
        
        Objects may be proxied:
        
          >>> from zope.security.checker import ProxyFactory
          >>> ob = ProxyFactory(ob)
          >>> interaction.checkPermission('P1', ob)
          False
          >>> interaction.checkPermission('P2', ob)
          False
          >>> interaction.checkPermission('P3', ob)
          True
          >>> interaction.checkPermission('P1G', ob)
          False
          >>> interaction.checkPermission('P2G', ob)
          False
          >>> interaction.checkPermission('P3G', ob)
          True
          >>> interaction.checkPermission('P4G', ob)
          True
        
        as may their parents:
        
          >>> ob3 = C()
          >>> ob3.__parent__ = ob
        
          >>> interaction.checkPermission('P1', ob3)
          False
          >>> interaction.checkPermission('P2', ob3)
          False
          >>> interaction.checkPermission('P3', ob3)
          True
          >>> interaction.checkPermission('P1G', ob3)
          False
          >>> interaction.checkPermission('P2G', ob3)
          False
          >>> interaction.checkPermission('P3G', ob3)
          True
          >>> interaction.checkPermission('P4G', ob3)
          True
        
        Groups
        ------
        
        Principals may have groups.  Groups are also principals (and, thus,
        may have groups).
        
        If a principal has groups, the groups are available as group ids in
        the principal's `groups` attribute.  The interaction has to convert
        these group ids to group objects, so that it can tell whether the
        groups have groups.  It does this by calling the `getPrincipal` method
        on the principal authentication service, which is responsible for,
        among other things, converting a principal id to a principal.
        For our examples here, we'll create and register a stub principal
        authentication service:
        
          >>> from zope.authentication.interfaces import IAuthentication
          >>> class FauxPrincipals(object):
          ...     zope.interface.implements(IAuthentication)
          ...     def __init__(self):
          ...         self.data = {}
          ...     def __setitem__(self, key, value):
          ...         self.data[key] = value
          ...     def __getitem__(self, key):
          ...         return self.data[key]
          ...     def getPrincipal(self, id):
          ...         return self.data[id]
        
          >>> auth = FauxPrincipals()
        
          >>> from zope.component import provideUtility
          >>> provideUtility(auth, IAuthentication)
        
        Let's define a group:
        
          >>> auth['g1'] = Principal('g1')
        
        Let's put the principal in our group.  We do that by adding the group id
        to the new principals groups:
        
          >>> principal.groups.append('g1')
        
        Of course, the principal doesn't have permissions not granted:
        
          >>> interaction.checkPermission('gP1', ob)
          False
        
        Now, if we grant a permission to the group:
        
          >>> prinper.grantPermissionToPrincipal('gP1', 'g1')
        
        We see that our principal has the permission:
        
          >>> interaction.checkPermission('gP1', ob)
          True
        
        This works even if the group grant is global:
        
          >>> interaction.checkPermission('gP1G', ob)
          False
        
          >>> prinperG.grantPermissionToPrincipal('gP1G', 'g1', True)
        
          >>> interaction.checkPermission('gP1G', ob)
          True
        
        Grants are, of course, acquired:
        
          >>> interaction.checkPermission('gP1', ob2)
          True
        
          >>> interaction.checkPermission('gP1G', ob2)
          True
        
        Inner grants can override outer grants:
        
          >>> prinper2.denyPermissionToPrincipal('gP1', 'g1')
          >>> interaction.checkPermission('gP1', ob2)
          False
        
        But principal grants always trump group grants:
        
          >>> prinper2.grantPermissionToPrincipal('gP1', 'bob')
          >>> interaction.checkPermission('gP1', ob2)
          True
        
        Groups can have groups too:
        
          >>> auth['g2'] = Principal('g2')
          >>> auth['g1'].groups.append('g2')
        
        If we grant to the new group:
        
          >>> prinper.grantPermissionToPrincipal('gP2', 'g2')
        
        Then we, of course have that permission too:
        
          >>> interaction.checkPermission('gP2', ob2)
          True
        
        Just as principal grants override group grants, group grants can
        override other group grants:
        
          >>> prinper.denyPermissionToPrincipal('gP2', 'g1')
          >>> interaction.checkPermission('gP2', ob2)
          False
        
        Principals can be in more than one group. Let's define a new group:
        
          >>> auth['g3'] = Principal('g3')
          >>> principal.groups.append('g3')
          >>> prinper.grantPermissionToPrincipal('gP2', 'g3')
        
        Now, the principal has two groups. In one group, the permission 'gP2'
        is denied, but in the other, it is allowed.  In a case like this, the
        permission is allowed:
        
          >>> interaction.checkPermission('gP2', ob2)
          True
        
        In a case where a principal has two or more groups, the group denies
        prevent allows from their parents. They don't prevent the principal
        from getting an allow from another principal.
        
        Grants can be inherited from ancestor groups through multiple paths.
        Let's grant a permission to g2 and deny it to g1:
        
          >>> prinper.grantPermissionToPrincipal('gP3', 'g2')
          >>> prinper.denyPermissionToPrincipal('gP3', 'g1')
        
        Now, as before, the deny in g1 blocks the grant in g2:
        
          >>> interaction.checkPermission('gP3', ob2)
          False
        
        Let's make g2 a group of g3:
        
          >>> auth['g3'].groups.append('g2')
        
        Now, we get g2's grant through g3, and access is allowed:
        
          >>> interaction.invalidate_cache()
          >>> interaction.checkPermission('gP3', ob2)
          True
        
        We can assign roles to groups:
        
          >>> prinrole.assignRoleToPrincipal('gR1', 'g2')
        
        and get permissions through the roles:
        
          >>> roleper.grantPermissionToRole('gP4', 'gR1')
          >>> interaction.checkPermission('gP4', ob2)
          True
        
        we can override role assignments to groups through subgroups:
        
          >>> prinrole.removeRoleFromPrincipal('gR1', 'g1')
          >>> prinrole.removeRoleFromPrincipal('gR1', 'g3')
          >>> interaction.checkPermission('gP4', ob2)
          False
        
        and through principals:
        
          >>> prinrole.assignRoleToPrincipal('gR1', 'bob')
          >>> interaction.checkPermission('gP4', ob2)
          True
        
        
        We clean up the changes we made in these examples:
        
          >>> zope.security.management.endInteraction()
          >>> ignore = zope.security.management.setSecurityPolicy(oldpolicy)
        
        
        =======
        CHANGES
        =======
        
        3.7.0 (2010-09-25)
        ------------------
        
        - LP #131115: Clean up inconsistency in ``getSetting`` interface definitions
          and actual usage for the various security maps.
        
        - LP #564525:  fix permission moved from ``zope.app.dublincore`` namespace
          to ``zope.dublincore``.
        
        - Removed unused imports and pep8 cleanup.
        
        - Use doctest module instead of the deprecated zope.testing.doctest.
        
        - AnnotationGrantInfo implements IGrantInfo.
        
        - Added test extra to declare test dependency on ``zope.component [test]``.
        
        - Added an extra named `dublincore` to express optional dependency on
          `zope.dublincore >= 3.7`.
        
        - Added tests for ZCML files making sure they include everything they need.
        
        
        3.6.1 (2009-07-24)
        ------------------
        
        - Make tests work when the default and Zope vocabulary registry compete in the
          cleanup.
        
        3.6.0 (2009-03-14)
        ------------------
        
        - Change ``zope.app.security`` dependency to the new ``zope.authentication``
          package, dropping a big number of unused dependencies.
        
        - Get rid of ``zope.app.testing`` and other testing dependencices.
        
        - Add ``ZODB3`` to install dependencies, because we use `Persistent`
          class. We didn't fail before, because it was installed implicitly.
        
        3.5.1 (2009-03-10)
        ------------------
        
        - Don't depend on the `hook` extra of zope.component, as we don't need
          it explicitly.
        
        - Import security settings (Allow, Deny, Unset) in the ``interfaces``
          module from the ``zope.securitypolicy.settings``, added in previous
          release instead of old ``zope.app.security.settings``.
          The ``zope.app.security`` will be adapted to import them from
          ``zope.securitypolicy.interfaces``.
        
        - Use `_z_instances` instead of `__instances__` for storing instances
          for ``zope.securitypolicy.settings.PermissionSetting`` singleton
          implementation, because __*__ name pattern is reserved for special
          names in python.
        
        - Add security protections for the `PermissionSetting`.
        
        - Improve documentation formatting, add it to the package's long
          description.
        
        - Remove unneeded dependencies.
        
        - Remove old zpkg-related files and zcml slugs.
        
        3.5.0 (2009-01-31)
        ------------------
        
        - Include settings that were previously imported from zope.app.security.
        
        3.4.2 (2009-01-28)
        ------------------
        
        - Changed mailing list address to zope-dev at zope.org. Fix package
          homepage to the pypi page.
        
        - Fix test in buildout which still depended on zope.app.securitypolicy
          by mistake.
        
        - Remove explicit dependency on zope.app.form from ``setup.py``; nothing
          in the code directly depends on this.
        
        3.4.1 (2008-06-02)
        ------------------
        
        - Fix reference to deprecated security policy from ZCML.
        
        3.4.0 (2007-09-25)
        ------------------
        
        - Initial documented release
        
Keywords: zope3 security policy
Platform: UNKNOWN
Classifier: Development Status :: 5 - Production/Stable
Classifier: Environment :: Web Environment
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: Zope Public License
Classifier: Programming Language :: Python
Classifier: Natural Language :: English
Classifier: Operating System :: OS Independent
Classifier: Topic :: Internet :: WWW/HTTP
Classifier: Framework :: Zope3