| # 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_netifcon_record = namedtuple("modified_netifcon", ["rule", |
| "added_context", |
| "removed_context", |
| "added_packet", |
| "removed_packet"]) |
| |
| |
| class NetifconsDifference(Difference): |
| |
| """Determine the difference in netifcons between two policies.""" |
| |
| added_netifcons = DiffResultDescriptor("diff_netifcons") |
| removed_netifcons = DiffResultDescriptor("diff_netifcons") |
| modified_netifcons = DiffResultDescriptor("diff_netifcons") |
| |
| def diff_netifcons(self): |
| """Generate the difference in netifcons between the policies.""" |
| |
| self.log.info("Generating netifcon differences from {0.left_policy} to {0.right_policy}". |
| format(self)) |
| |
| self.added_netifcons, self.removed_netifcons, matched_netifcons = self._set_diff( |
| (NetifconWrapper(n) for n in self.left_policy.netifcons()), |
| (NetifconWrapper(n) for n in self.right_policy.netifcons())) |
| |
| self.modified_netifcons = [] |
| |
| for left_netifcon, right_netifcon in matched_netifcons: |
| # Criteria for modified netifcons |
| # 1. change to context |
| # 2. change to packet context |
| if ContextWrapper(left_netifcon.context) != ContextWrapper(right_netifcon.context): |
| removed_context = left_netifcon.context |
| added_context = right_netifcon.context |
| else: |
| removed_context = None |
| added_context = None |
| |
| if ContextWrapper(left_netifcon.packet) != ContextWrapper(right_netifcon.packet): |
| removed_packet = left_netifcon.packet |
| added_packet = right_netifcon.packet |
| else: |
| removed_packet = None |
| added_packet = None |
| |
| if removed_context or removed_packet: |
| self.modified_netifcons.append(modified_netifcon_record( |
| left_netifcon, added_context, removed_context, added_packet, removed_packet)) |
| |
| # |
| # Internal functions |
| # |
| def _reset_diff(self): |
| """Reset diff results on policy changes.""" |
| self.log.debug("Resetting netifcon differences") |
| self.added_netifcons = None |
| self.removed_netifcons = None |
| self.modified_netifcons = None |
| |
| |
| class NetifconWrapper(Wrapper): |
| |
| """Wrap netifcon statements for diff purposes.""" |
| |
| def __init__(self, ocon): |
| self.origin = ocon |
| self.netif = ocon.netif |
| self.key = hash(ocon) |
| |
| def __hash__(self): |
| return self.key |
| |
| def __lt__(self, other): |
| return self.netif < other.netif |
| |
| def __eq__(self, other): |
| return self.netif == other.netif |
