blob: 24f0a7d53b5523908eccfa67a6ebd50a6ba7968a [file] [log] [blame]
# 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_genfs_record = namedtuple("modified_genfs", ["rule",
"added_context",
"removed_context"])
class GenfsconsDifference(Difference):
"""Determine the difference in genfscon rules between two policies."""
added_genfscons = DiffResultDescriptor("diff_genfscons")
removed_genfscons = DiffResultDescriptor("diff_genfscons")
modified_genfscons = DiffResultDescriptor("diff_genfscons")
def diff_genfscons(self):
"""Generate the difference in genfscon rules between the policies."""
self.log.info(
"Generating genfscon differences from {0.left_policy} to {0.right_policy}".
format(self))
self.added_genfscons, self.removed_genfscons, matched = self._set_diff(
(GenfsconWrapper(fs) for fs in self.left_policy.genfscons()),
(GenfsconWrapper(fs) for fs in self.right_policy.genfscons()))
self.modified_genfscons = []
for left_rule, right_rule in matched:
# Criteria for modified rules
# 1. change to context
if ContextWrapper(left_rule.context) != ContextWrapper(right_rule.context):
self.modified_genfscons.append(modified_genfs_record(left_rule,
right_rule.context,
left_rule.context))
#
# Internal functions
#
def _reset_diff(self):
"""Reset diff results on policy changes."""
self.log.debug("Resetting genfscon rule differences")
self.added_genfscons = None
self.removed_genfscons = None
self.modified_genfscons = None
class GenfsconWrapper(Wrapper):
"""Wrap genfscon rules to allow set operations."""
def __init__(self, rule):
self.origin = rule
self.fs = rule.fs
self.path = rule.path
self.filetype = rule.filetype
self.context = ContextWrapper(rule.context)
self.key = hash(rule)
def __hash__(self):
return self.key
def __lt__(self, other):
return self.key < other.key
def __eq__(self, other):
return self.fs == other.fs and \
self.path == other.path and \
self.filetype == other.filetype