| # Copyright 2016, 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 .context import ContextWrapper |
| from .descriptors import DiffResultDescriptor |
| from .difference import Difference, Wrapper |
| |
| |
| modified_portcon_record = namedtuple("modified_portcon", ["rule", |
| "added_context", |
| "removed_context"]) |
| |
| |
| class PortconsDifference(Difference): |
| |
| """Determine the difference in portcons between two policies.""" |
| |
| added_portcons = DiffResultDescriptor("diff_portcons") |
| removed_portcons = DiffResultDescriptor("diff_portcons") |
| modified_portcons = DiffResultDescriptor("diff_portcons") |
| |
| def diff_portcons(self): |
| """Generate the difference in portcons between the policies.""" |
| |
| self.log.info("Generating portcon differences from {0.left_policy} to {0.right_policy}". |
| format(self)) |
| |
| self.added_portcons, self.removed_portcons, matched_portcons = self._set_diff( |
| (PortconWrapper(n) for n in self.left_policy.portcons()), |
| (PortconWrapper(n) for n in self.right_policy.portcons())) |
| |
| self.modified_portcons = [] |
| |
| for left_portcon, right_portcon in matched_portcons: |
| # Criteria for modified portcons |
| # 1. change to context |
| if ContextWrapper(left_portcon.context) != ContextWrapper(right_portcon.context): |
| self.modified_portcons.append(modified_portcon_record(left_portcon, |
| right_portcon.context, |
| left_portcon.context)) |
| |
| # |
| # Internal functions |
| # |
| def _reset_diff(self): |
| """Reset diff results on policy changes.""" |
| self.log.debug("Resetting portcon differences") |
| self.added_portcons = None |
| self.removed_portcons = None |
| self.modified_portcons = None |
| |
| |
| class PortconWrapper(Wrapper): |
| |
| """Wrap portcon statements for diff purposes.""" |
| |
| def __init__(self, ocon): |
| self.origin = ocon |
| self.protocol = ocon.protocol |
| self.low, self.high = ocon.ports |
| self.key = hash(ocon) |
| |
| def __hash__(self): |
| return self.key |
| |
| def __lt__(self, other): |
| return self.origin < other.origin |
| |
| def __eq__(self, other): |
| return self.protocol == other.protocol and \ |
| self.low == other.low and \ |
| self.high == other.high |
