freeipa/ipaserver/install/plugins/update_managed_permissions.py

# Authors:
#   Petr Viktorin <pviktori@redhat.com>
#
# Copyright (C) 2014  Red Hat
# see file 'COPYING' for use and warranty information
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

from ipalib import errors
from ipapython.dn import DN
from ipalib.plugable import Registry
from ipalib.plugins import aci
from ipalib.plugins.permission import permission
from ipaserver.plugins.ldap2 import ldap2
from ipaserver.install.plugins import LAST
from ipaserver.install.plugins.baseupdate import PostUpdate


register = Registry()


@register()
class update_managed_permissions(PostUpdate):
    """Update managed permissions after an update.

    Update managed permissions according to templates specified in plugins.
    For read permissions, puts any attributes specified in the legacy
    Anonymous access ACI in the exclude list when creating the permission.
    """
    order = LAST

    def get_anonymous_read_blacklist(self, ldap):
        """Get the list of attributes from the legacy anonymous access ACI"""
        aciname = u'Enable Anonymous access'
        aciprefix = u'none'

        base_entry = ldap.get_entry(self.api.env.basedn, ['aci'])

        acistrs = base_entry.get('aci', [])
        acilist = aci._convert_strings_to_acis(acistrs)
        try:
            rawaci = aci._find_aci_by_name(acilist, aciprefix, aciname)
        except errors.NotFound:
            self.log.info('Anonymous ACI not found, using no blacklist')
            return []

        return rawaci.target['targetattr']['expression']

    def execute(self, **options):
        ldap = self.api.Backend[ldap2]

        anonymous_read_blacklist = self.get_anonymous_read_blacklist(ldap)

        self.log.info('Anonymous read blacklist: %s', anonymous_read_blacklist)

        for obj in self.api.Object():
            managed_permissions = getattr(obj, 'managed_permissions', {})
            if managed_permissions:
                self.log.info('Updating managed permissions for %s', obj.name)
            for name, template in managed_permissions.items():
                assert name.startswith('System:')
                self.update_permission(ldap,
                                       obj,
                                       unicode(name),
                                       template,
                                       anonymous_read_blacklist)

        return False, False, ()

    def update_permission(self, ldap, obj, name, template,
                          anonymous_read_blacklist):
        """Update the given permission and the corresponding ACI"""
        dn = self.api.Object[permission].get_dn(name)

        try:
            attrs_list = self.api.Object[permission].default_attributes
            entry = ldap.get_entry(dn, attrs_list)
            is_new = False
        except errors.NotFound:
            entry = ldap.make_entry(dn)
            is_new = True

        self.log.info('Updating managed permission: %s', name)
        self.update_entry(obj, entry, template,
                          anonymous_read_blacklist, is_new=is_new)

        if is_new:
            ldap.add_entry(entry)
        else:
            try:
                ldap.update_entry(entry)
            except errors.EmptyModlist:
                self.log.debug('No changes to permission: %s', name)
                return

        self.log.debug('Updating ACI for managed permission: %s', name)

        self.api.Object[permission].update_aci(entry)

    def update_entry(self, obj, entry, template,
                     anonymous_read_blacklist, is_new):
        """Update the given permission Entry (without contacting LDAP)"""

        [name_ava] = entry.dn[0]
        assert name_ava.attr == 'cn'
        name = name_ava.value
        entry.single_value['cn'] = name

        template = dict(template)

        # Common attributes
        entry['objectclass'] = self.api.Object[permission].object_class

        entry['ipapermissiontype'] = [u'SYSTEM', u'V2', u'MANAGED']

        # Object-specific attributes
        ldap_filter = ['(objectclass=%s)' % oc
                       for oc in obj.permission_filter_objectclasses]
        entry['ipapermtargetfilter'] = ldap_filter

        ipapermlocation = DN(obj.container_dn, self.api.env.basedn)
        entry.single_value['ipapermlocation'] = ipapermlocation

        # Attributes from template
        bindruletype = template.pop('ipapermbindruletype')
        entry.single_value['ipapermbindruletype'] = bindruletype

        entry['ipapermright'] = list(template.pop('ipapermright'))

        # Add to the set of default attributes
        attributes = set(template.pop('ipapermdefaultattr', ()))
        attributes.update(entry.get('ipapermdefaultattr', ()))
        attributes = set(a.lower() for a in attributes)
        entry['ipapermdefaultattr'] = list(attributes)

        # Exclude attributes filtered from the global read ACI
        if template.pop('replaces_global_anonymous_aci', False) and is_new:
            read_blacklist = set(a.lower() for a in anonymous_read_blacklist)
            read_blacklist &= attributes
            if read_blacklist:
                self.log.info('Excluded attributes for %s: %s',
                              name, ', '.join(read_blacklist))
                entry['ipapermexcludedattr'] = list(read_blacklist)

        # Sanity check
        if template:
            raise ValueError(
                'Unknown key(s) in managed permission template %s: %s' % (
                    name, ', '.join(template.keys())))