"""STIX 2.0 Objects that are neither SDOs nor SROs.""" from collections import OrderedDict import importlib import pkgutil import stix2 from . import exceptions from .base import _STIXBase from .properties import IDProperty, ListProperty, Property, TypeProperty from .utils import _get_dict, get_class_hierarchy_names class STIXObjectProperty(Property): def __init__(self, allow_custom=False, *args, **kwargs): self.allow_custom = allow_custom super(STIXObjectProperty, self).__init__(*args, **kwargs) def clean(self, value): # Any STIX Object (SDO, SRO, or Marking Definition) can be added to # a bundle with no further checks. if any(x in ('STIXDomainObject', 'STIXRelationshipObject', 'MarkingDefinition') for x in get_class_hierarchy_names(value)): return value try: dictified = _get_dict(value) except ValueError: raise ValueError("This property may only contain a dictionary or object") if dictified == {}: raise ValueError("This property may only contain a non-empty dictionary or object") if 'type' in dictified and dictified['type'] == 'bundle': raise ValueError('This property may not contain a Bundle object') if self.allow_custom: parsed_obj = parse(dictified, allow_custom=True) else: parsed_obj = parse(dictified) return parsed_obj class Bundle(_STIXBase): """For more detailed information on this object's properties, see `the STIX 2.0 specification `__. """ _type = 'bundle' _properties = OrderedDict() _properties.update([ ('type', TypeProperty(_type)), ('id', IDProperty(_type)), ('spec_version', Property(fixed="2.0")), ('objects', ListProperty(STIXObjectProperty)), ]) def __init__(self, *args, **kwargs): # Add any positional arguments to the 'objects' kwarg. if args: if isinstance(args[0], list): kwargs['objects'] = args[0] + list(args[1:]) + kwargs.get('objects', []) else: kwargs['objects'] = list(args) + kwargs.get('objects', []) self.__allow_custom = kwargs.get('allow_custom', False) self._properties['objects'].contained.allow_custom = kwargs.get('allow_custom', False) super(Bundle, self).__init__(**kwargs) STIX2_OBJ_MAPS = {} def parse(data, allow_custom=False, version=None): """Convert a string, dict or file-like object into a STIX object. Args: data (str, dict, file-like object): The STIX 2 content to be parsed. allow_custom (bool): Whether to allow custom properties as well unknown custom objects. Note that unknown custom objects cannot be parsed into STIX objects, and will be returned as is. Default: False. version (str): Which STIX2 version to use. (e.g. "2.0", "2.1"). If None, use latest version. Returns: An instantiated Python STIX object. WARNING: 'allow_custom=True' will allow for the return of any supplied STIX dict(s) that cannot be found to map to any known STIX object types (both STIX2 domain objects or defined custom STIX2 objects); NO validation is done. This is done to allow the processing of possibly unknown custom STIX objects (example scenario: I need to query a third-party TAXII endpoint that could provide custom STIX objects that I dont know about ahead of time) """ # convert STIX object to dict, if not already obj = _get_dict(data) # convert dict to full python-stix2 obj obj = dict_to_stix2(obj, allow_custom, version) return obj def dict_to_stix2(stix_dict, allow_custom=False, version=None): """convert dictionary to full python-stix2 object Args: stix_dict (dict): a python dictionary of a STIX object that (presumably) is semantically correct to be parsed into a full python-stix2 obj allow_custom (bool): Whether to allow custom properties as well unknown custom objects. Note that unknown custom objects cannot be parsed into STIX objects, and will be returned as is. Default: False. Returns: An instantiated Python STIX object WARNING: 'allow_custom=True' will allow for the return of any supplied STIX dict(s) that cannot be found to map to any known STIX object types (both STIX2 domain objects or defined custom STIX2 objects); NO validation is done. This is done to allow the processing of possibly unknown custom STIX objects (example scenario: I need to query a third-party TAXII endpoint that could provide custom STIX objects that I dont know about ahead of time) """ if not version: # Use latest version v = 'v' + stix2.DEFAULT_VERSION.replace('.', '') else: v = 'v' + version.replace('.', '') OBJ_MAP = STIX2_OBJ_MAPS[v] if 'type' not in stix_dict: raise exceptions.ParseError("Can't parse object with no 'type' property: %s" % str(stix_dict)) try: obj_class = OBJ_MAP[stix_dict['type']] except KeyError: if allow_custom: # flag allows for unknown custom objects too, but will not # be parsed into STIX object, returned as is return stix_dict raise exceptions.ParseError("Can't parse unknown object type '%s'! For custom types, use the CustomObject decorator." % stix_dict['type']) return obj_class(allow_custom=allow_custom, **stix_dict) def _register_type(new_type, version=None): """Register a custom STIX Object type. Args: new_type (class): A class to register in the Object map. version (str): Which STIX2 version to use. (e.g. "2.0", "2.1"). If None, use latest version. """ if not version: # Use latest version v = 'v' + stix2.DEFAULT_VERSION.replace('.', '') else: v = 'v' + version.replace('.', '') OBJ_MAP = STIX2_OBJ_MAPS[v] OBJ_MAP[new_type._type] = new_type def _collect_stix2_obj_maps(): """Navigate the package once and retrieve all OBJ_MAP dicts for each v2X package.""" if not STIX2_OBJ_MAPS: top_level_module = importlib.import_module('stix2') path = top_level_module.__path__ prefix = str(top_level_module.__name__) + '.' for module_loader, name, is_pkg in pkgutil.walk_packages(path=path, prefix=prefix): if name.startswith('stix2.v2') and is_pkg: mod = importlib.import_module(name, str(top_level_module.__name__)) STIX2_OBJ_MAPS[name.split('.')[-1]] = mod.OBJ_MAP