# Copyright 2016, Tresys Technology, LLC # # SPDX-License-Identifier: LGPL-2.1-only # from typing import NamedTuple from ..policyrep import Context, Portcon from .context import ContextWrapper from .descriptors import DiffResultDescriptor from .difference import Difference, Wrapper class ModifiedPortcon(NamedTuple): """Difference details for a modified portcon.""" rule: Portcon added_context: Context removed_context: 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) -> None: """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(ModifiedPortcon(left_portcon, right_portcon.context, left_portcon.context)) # # Internal functions # def _reset_diff(self) -> None: """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[Portcon]): """Wrap portcon statements for diff purposes.""" __slots__ = ("protocol", "low", "high") def __init__(self, ocon: Portcon) -> None: 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