| # Copyright 2015, Tresys Technology, LLC |
| # |
| # This file is part of SETools. |
| # |
| # SETools is free software: you can redistribute it and/or modify |
| # it under the terms of the GNU Lesser General Public License as |
| # published by the Free Software Foundation, either version 2.1 of |
| # the License, or (at your option) any later version. |
| # |
| # SETools 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 Lesser General Public License for more details. |
| # |
| # You should have received a copy of the GNU Lesser General Public |
| # License along with SETools. If not, see |
| # <http://www.gnu.org/licenses/>. |
| # |
| from collections import namedtuple |
| |
| from .descriptors import DiffResultDescriptor |
| from .difference import Difference, SymbolWrapper |
| |
| |
| modified_commons_record = namedtuple("modified_common", ["added_perms", |
| "removed_perms", |
| "matched_perms"]) |
| |
| |
| class CommonDifference(Difference): |
| |
| """ |
| Determine the difference in common permission sets |
| between two policies. |
| """ |
| |
| added_commons = DiffResultDescriptor("diff_commons") |
| removed_commons = DiffResultDescriptor("diff_commons") |
| modified_commons = DiffResultDescriptor("diff_commons") |
| |
| def diff_commons(self): |
| """Generate the difference in commons between the policies.""" |
| |
| self.log.info( |
| "Generating common differences from {0.left_policy} to {0.right_policy}".format(self)) |
| |
| self.added_commons, self.removed_commons, matched_commons = self._set_diff( |
| (SymbolWrapper(c) for c in self.left_policy.commons()), |
| (SymbolWrapper(c) for c in self.right_policy.commons())) |
| |
| self.modified_commons = dict() |
| |
| for left_common, right_common in matched_commons: |
| # Criteria for modified commons |
| # 1. change to permissions |
| added_perms, removed_perms, matched_perms = self._set_diff(left_common.perms, |
| right_common.perms) |
| |
| if added_perms or removed_perms: |
| self.modified_commons[left_common] = modified_commons_record(added_perms, |
| removed_perms, |
| matched_perms) |
| |
| # |
| # Internal functions |
| # |
| def _reset_diff(self): |
| """Reset diff results on policy changes.""" |
| self.log.debug("Resetting common differences") |
| self.added_commons = None |
| self.removed_commons = None |
| self.modified_commons = None |
