| # 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_types_record = namedtuple("modified_type", ["added_attributes", |
| "removed_attributes", |
| "matched_attributes", |
| "modified_permissive", |
| "permissive", |
| "added_aliases", |
| "removed_aliases", |
| "matched_aliases"]) |
| |
| |
| class TypesDifference(Difference): |
| |
| """Determine the difference in types between two policies.""" |
| |
| added_types = DiffResultDescriptor("diff_types") |
| removed_types = DiffResultDescriptor("diff_types") |
| modified_types = DiffResultDescriptor("diff_types") |
| |
| def diff_types(self): |
| """Generate the difference in types between the policies.""" |
| |
| self.log.info( |
| "Generating type differences from {0.left_policy} to {0.right_policy}".format(self)) |
| |
| self.added_types, self.removed_types, matched_types = self._set_diff( |
| (SymbolWrapper(t) for t in self.left_policy.types()), |
| (SymbolWrapper(t) for t in self.right_policy.types())) |
| |
| self.modified_types = dict() |
| |
| for left_type, right_type in matched_types: |
| # Criteria for modified types |
| # 1. change to attribute set, or |
| # 2. change to alias set, or |
| # 3. different permissive setting |
| added_attr, removed_attr, matched_attr = self._set_diff( |
| (SymbolWrapper(a) for a in left_type.attributes()), |
| (SymbolWrapper(a) for a in right_type.attributes())) |
| |
| added_aliases, removed_aliases, matched_aliases = self._set_diff(left_type.aliases(), |
| right_type.aliases()) |
| |
| left_permissive = left_type.ispermissive |
| right_permissive = right_type.ispermissive |
| mod_permissive = left_permissive != right_permissive |
| |
| if added_attr or removed_attr or added_aliases or removed_aliases or mod_permissive: |
| self.modified_types[left_type] = modified_types_record(added_attr, |
| removed_attr, |
| matched_attr, |
| mod_permissive, |
| left_permissive, |
| added_aliases, |
| removed_aliases, |
| matched_aliases) |
| |
| # |
| # Internal functions |
| # |
| def _reset_diff(self): |
| """Reset diff results on policy changes.""" |
| self.log.debug("Resetting type differences") |
| self.added_types = None |
| self.removed_types = None |
| self.modified_types = None |
