1 # Copyright 2016, Tresys Technology, LLC 2 # 3 # This file is part of SETools. 4 # 5 # SETools is free software: you can redistribute it and/or modify 6 # it under the terms of the GNU Lesser General Public License as 7 # published by the Free Software Foundation, either version 2.1 of 8 # the License, or (at your option) any later version. 9 # 10 # SETools is distributed in the hope that it will be useful, 11 # but WITHOUT ANY WARRANTY; without even the implied warranty of 12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 # GNU Lesser General Public License for more details. 14 # 15 # You should have received a copy of the GNU Lesser General Public 16 # License along with SETools. If not, see 17 # <http://www.gnu.org/licenses/>. 18 # 19 from collections import namedtuple 20 21 from .descriptors import DiffResultDescriptor 22 from .difference import Difference, SymbolWrapper, Wrapper 23 24 25 modified_default_record = namedtuple("modified_default", ["rule", 26 "added_default", 27 "removed_default", 28 "added_default_range", 29 "removed_default_range"]) 30 31 32 class DefaultsDifference(Difference): 33 34 """Determine the difference in default_* between two policies.""" 35 36 added_defaults = DiffResultDescriptor("diff_defaults") 37 removed_defaults = DiffResultDescriptor("diff_defaults") 38 modified_defaults = DiffResultDescriptor("diff_defaults") 39 40 def diff_defaults(self): 41 """Generate the difference in type defaults between the policies.""" 42 43 self.log.info( 44 "Generating default_* differences from {0.left_policy} to {0.right_policy}". 45 format(self)) 46 47 self.added_defaults, self.removed_defaults, matched_defaults = self._set_diff( 48 (DefaultWrapper(d) for d in self.left_policy.defaults()), 49 (DefaultWrapper(d) for d in self.right_policy.defaults())) 50 51 self.modified_defaults = [] 52 53 for left_default, right_default in matched_defaults: 54 # Criteria for modified defaults 55 # 1. change to default setting 56 # 2. change to default range 57 58 if left_default.default != right_default.default: 59 removed_default = left_default.default 60 added_default = right_default.default 61 else: 62 removed_default = None 63 added_default = None 64 65 try: 66 if left_default.default_range != right_default.default_range: 67 removed_default_range = left_default.default_range 68 added_default_range = right_default.default_range 69 else: 70 removed_default_range = None 71 added_default_range = None 72 except AttributeError: 73 removed_default_range = None 74 added_default_range = None 75 76 if removed_default or removed_default_range: 77 self.modified_defaults.append( 78 modified_default_record(left_default, 79 added_default, 80 removed_default, 81 added_default_range, 82 removed_default_range)) 83 84 # 85 # Internal functions 86 # 87 def _reset_diff(self): 88 """Reset diff results on policy changes.""" 89 self.log.debug("Resetting default_* differences") 90 self.added_defaults = None 91 self.removed_defaults = None 92 self.modified_defaults = None 93 94 95 class DefaultWrapper(Wrapper): 96 97 """Wrap default_* to allow comparisons.""" 98 99 def __init__(self, default): 100 self.origin = default 101 self.ruletype = default.ruletype 102 self.tclass = SymbolWrapper(default.tclass) 103 self.key = hash(default) 104 105 def __hash__(self): 106 return self.key 107 108 def __lt__(self, other): 109 return self.key < other.key 110 111 def __eq__(self, other): 112 return self.ruletype == other.ruletype and \ 113 self.tclass == other.tclass 114
