# Copyright 2014-2015, Tresys Technology, LLC # # SPDX-License-Identifier: LGPL-2.1-only # import logging from typing import cast, Iterable, Optional, Set, Tuple from . import mixins, query from .descriptors import CriteriaDescriptor, CriteriaSetDescriptor from .exception import RuleUseError, RuleNotConditional from .policyrep import AnyTERule, AVRuleXperm, IoctlSet, TERuletype from .util import match_indirect_regex, match_regex_or_set class TERuleQuery(mixins.MatchObjClass, mixins.MatchPermission, query.PolicyQuery): """ Query the Type Enforcement rules. Parameter: policy The policy to query. Keyword Parameters/Class attributes: ruletype The list of rule type(s) to match. source The name of the source type/attribute to match. source_indirect If true, members of an attribute will be matched rather than the attribute itself. Default is true. source_regex If true, regular expression matching will be used on the source type/attribute. Obeys the source_indirect option. Default is false. target The name of the target type/attribute to match. target_indirect If true, members of an attribute will be matched rather than the attribute itself. Default is true. target_regex If true, regular expression matching will be used on the target type/attribute. Obeys target_indirect option. Default is false. tclass The object class(es) to match. tclass_regex If true, use a regular expression for matching the rule's object class. Default is false. perms The set of permission(s) to match. perms_equal If true, the permission set of the rule must exactly match the permissions criteria. If false, any set intersection will match. Default is false. perms_regex If true, regular expression matching will be used on the permission names instead of set logic. Default is false. perms_subset If true, the rule matches if the permissions criteria is a subset of the rule's permission set. Default is false. default The name of the default type to match. default_regex If true, regular expression matching will be used on the default type. Default is false. boolean The set of boolean(s) to match. boolean_regex If true, regular expression matching will be used on the booleans. Default is false. boolean_equal If true, the booleans in the conditional expression of the rule must exactly match the criteria. If false, any set intersection will match. Default is false. """ ruletype = CriteriaSetDescriptor(enum_class=TERuletype) source = CriteriaDescriptor("source_regex", "lookup_type_or_attr") source_regex: bool = False source_indirect: bool = True target = CriteriaDescriptor("target_regex", "lookup_type_or_attr") target_regex: bool = False target_indirect: bool = True default = CriteriaDescriptor("default_regex", "lookup_type_or_attr") default_regex: bool = False boolean = CriteriaSetDescriptor("boolean_regex", "lookup_boolean") boolean_regex: bool = False boolean_equal: bool = False _xperms: Optional[IoctlSet] = None xperms_equal: bool = False @property def xperms(self) -> Optional[IoctlSet]: return self._xperms @xperms.setter def xperms(self, value: Optional[Iterable[Tuple[int, int]]]) -> None: if value: pending_xperms: Set[int] = set() for low, high in value: if not (0 <= low <= 0xffff): raise ValueError("{0:#07x} is not a valid ioctl.".format(low)) if not (0 <= high <= 0xffff): raise ValueError("{0:#07x} is not a valid ioctl.".format(high)) if high < low: high, low = low, high pending_xperms.update(i for i in range(low, high + 1)) self._xperms = IoctlSet(pending_xperms) else: self._xperms = None def __init__(self, policy, **kwargs) -> None: super(TERuleQuery, self).__init__(policy, **kwargs) self.log = logging.getLogger(__name__) def results(self) -> Iterable[AnyTERule]: """Generator which yields all matching TE rules.""" self.log.info("Generating TE rule results from {0.policy}".format(self)) self.log.debug("Ruletypes: {0.ruletype}".format(self)) self.log.debug("Source: {0.source!r}, indirect: {0.source_indirect}, " "regex: {0.source_regex}".format(self)) self.log.debug("Target: {0.target!r}, indirect: {0.target_indirect}, " "regex: {0.target_regex}".format(self)) self._match_object_class_debug(self.log) self._match_perms_debug(self.log) self.log.debug("Xperms: {0.xperms!r}, eq: {0.xperms_equal}".format(self)) self.log.debug("Default: {0.default!r}, regex: {0.default_regex}".format(self)) self.log.debug("Boolean: {0.boolean!r}, eq: {0.boolean_equal}, " "regex: {0.boolean_regex}".format(self)) for rule in self.policy.terules(): # # Matching on rule type # if self.ruletype: if rule.ruletype not in self.ruletype: continue # # Matching on source type # if self.source and not match_indirect_regex( rule.source, self.source, self.source_indirect, self.source_regex): continue # # Matching on target type # if self.target and not match_indirect_regex( rule.target, self.target, self.target_indirect, self.target_regex): continue # # Matching on object class # if not self._match_object_class(rule): continue # # Matching on permission set # try: if self.perms and rule.extended: if self.perms_equal and len(self.perms) > 1: # if criteria is more than one standard permission, # extended perm rules can never match if the # permission set equality option is on. continue if cast(AVRuleXperm, rule).xperm_type not in self.perms: continue elif not self._match_perms(rule): continue except RuleUseError: continue # # Matching on extended permissions # try: if self.xperms and not match_regex_or_set( rule.perms, self.xperms, self.xperms_equal, False): continue except RuleUseError: continue # # Matching on default type # if self.default: try: # because default type is always a single # type, hard-code indirect to True # so the criteria can be an attribute if not match_indirect_regex( rule.default, self.default, True, self.default_regex): continue except RuleUseError: continue # # Match on Boolean in conditional expression # if self.boolean: try: if not match_regex_or_set( rule.conditional.booleans, self.boolean, self.boolean_equal, self.boolean_regex): continue except RuleNotConditional: continue # if we get here, we have matched all available criteria yield rule