"""Functions for working with STIX2 granular markings.""" from stix2 import exceptions from stix2.markings import utils from stix2.utils import new_version def get_markings(obj, selectors, inherited=False, descendants=False): """ Get all granular markings associated to with the properties. Args: obj: An SDO or SRO object. selectors: string or list of selector strings relative to the SDO or SRO in which the properties appear. inherited: If True, include markings inherited relative to the properties. descendants: If True, include granular markings applied to any children relative to the properties. Raises: InvalidSelectorError: If `selectors` fail validation. Returns: list: Marking identifiers that matched the selectors expression. """ selectors = utils.convert_to_list(selectors) utils.validate(obj, selectors) granular_markings = obj.get('granular_markings', []) if not granular_markings: return [] results = set() for marking in granular_markings: for user_selector in selectors: for marking_selector in marking.get('selectors', []): if any([ (user_selector == marking_selector), # Catch explicit selectors. (user_selector.startswith(marking_selector) and inherited), # Catch inherited selectors. (marking_selector.startswith(user_selector) and descendants), ]): # Catch descendants selectors refs = marking.get('marking_ref', []) results.update([refs]) return list(results) def set_markings(obj, marking, selectors): """ Remove all granular markings associated with selectors and append a new granular marking. Refer to `clear_markings` and `add_markings` for details. Args: obj: An SDO or SRO object. selectors: string or list of selector strings relative to the SDO or SRO in which the properties appear. marking: identifier or list of marking identifiers that apply to the properties selected by `selectors`. Returns: A new version of the given SDO or SRO with specified markings removed and new ones added. """ obj = clear_markings(obj, selectors) return add_markings(obj, marking, selectors) def remove_markings(obj, marking, selectors): """ Remove a granular marking from the granular_markings collection. Args: obj: An SDO or SRO object. marking: identifier or list of marking identifiers that apply to the properties selected by `selectors`. selectors: string or list of selectors strings relative to the SDO or SRO in which the properties appear. Raises: InvalidSelectorError: If `selectors` fail validation. MarkingNotFoundError: If markings to remove are not found on the provided SDO or SRO. Returns: A new version of the given SDO or SRO with specified markings removed. """ selectors = utils.convert_to_list(selectors) marking = utils.convert_to_marking_list(marking) utils.validate(obj, selectors) granular_markings = obj.get('granular_markings') if not granular_markings: return obj granular_markings = utils.expand_markings(granular_markings) to_remove = [] for m in marking: to_remove.append({'marking_ref': m, 'selectors': selectors}) remove = utils.build_granular_marking(to_remove).get('granular_markings') if not any(marking in granular_markings for marking in remove): raise exceptions.MarkingNotFoundError(obj, remove) granular_markings = [ m for m in granular_markings if m not in remove ] granular_markings = utils.compress_markings(granular_markings) if granular_markings: return new_version(obj, granular_markings=granular_markings, allow_custom=True) else: return new_version(obj, granular_markings=None, allow_custom=True) def add_markings(obj, marking, selectors): """ Append a granular marking to the granular_markings collection. Args: obj: An SDO or SRO object. marking: identifier or list of marking identifiers that apply to the properties selected by `selectors`. selectors: list of type string, selectors must be relative to the TLO in which the properties appear. Raises: InvalidSelectorError: If `selectors` fail validation. Returns: A new version of the given SDO or SRO with specified markings added. """ selectors = utils.convert_to_list(selectors) marking = utils.convert_to_marking_list(marking) utils.validate(obj, selectors) granular_marking = [] for m in marking: granular_marking.append({'marking_ref': m, 'selectors': sorted(selectors)}) if obj.get('granular_markings'): granular_marking.extend(obj.get('granular_markings')) granular_marking = utils.expand_markings(granular_marking) granular_marking = utils.compress_markings(granular_marking) return new_version(obj, granular_markings=granular_marking, allow_custom=True) def clear_markings(obj, selectors): """ Remove all granular markings associated with the selectors. Args: obj: An SDO or SRO object. selectors: string or list of selectors strings relative to the SDO or SRO in which the properties appear. Raises: InvalidSelectorError: If `selectors` fail validation. MarkingNotFoundError: If markings to remove are not found on the provided SDO or SRO. Returns: A new version of the given SDO or SRO with specified markings cleared. """ selectors = utils.convert_to_list(selectors) utils.validate(obj, selectors) granular_markings = obj.get('granular_markings') if not granular_markings: return obj granular_markings = utils.expand_markings(granular_markings) sdo = utils.build_granular_marking( [{'selectors': selectors, 'marking_ref': 'N/A'}], ) clear = sdo.get('granular_markings', []) if not any( clear_selector in sdo_selectors.get('selectors', []) for sdo_selectors in granular_markings for clear_marking in clear for clear_selector in clear_marking.get('selectors', []) ): raise exceptions.MarkingNotFoundError(obj, clear) for granular_marking in granular_markings: for s in selectors: if s in granular_marking.get('selectors', []): marking_refs = granular_marking.get('marking_ref') if marking_refs: granular_marking['marking_ref'] = '' granular_markings = utils.compress_markings(granular_markings) if granular_markings: return new_version(obj, granular_markings=granular_markings, allow_custom=True) else: return new_version(obj, granular_markings=None, allow_custom=True) def is_marked(obj, marking=None, selectors=None, inherited=False, descendants=False): """ Check if field is marked by any marking or by specific marking(s). Args: obj: An SDO or SRO object. marking: identifier or list of marking identifiers that apply to the properties selected by `selectors`. selectors: string or list of selectors strings relative to the SDO or SRO in which the properties appear. inherited: If True, return markings inherited from the given selector. descendants: If True, return granular markings applied to any children of the given selector. Raises: InvalidSelectorError: If `selectors` fail validation. Returns: bool: True if ``selectors`` is found on internal SDO or SRO collection. False otherwise. Note: When a list of marking identifiers is provided, if ANY of the provided marking identifiers match, True is returned. """ if selectors is None: raise TypeError("Required argument 'selectors' must be provided") selectors = utils.convert_to_list(selectors) marking = utils.convert_to_marking_list(marking) utils.validate(obj, selectors) granular_markings = obj.get('granular_markings', []) marked = False markings = set() for granular_marking in granular_markings: for user_selector in selectors: for marking_selector in granular_marking.get('selectors', []): if any([ (user_selector == marking_selector), # Catch explicit selectors. (user_selector.startswith(marking_selector) and inherited), # Catch inherited selectors. (marking_selector.startswith(user_selector) and descendants), ]): # Catch descendants selectors marking_ref = granular_marking.get('marking_ref', '') if marking and any(x == marking_ref for x in marking): markings.update([marking_ref]) marked = True if marking: # All user-provided markings must be found. return markings.issuperset(set(marking)) return marked