cti-python-stix2/stix2/v20/common.py

218 lines
7.7 KiB
Python

"""STIX 2.0 Common Data Types and Properties."""
from collections import OrderedDict
import copy
import six
from ..base import _STIXBase
from ..custom import _custom_marking_builder
from ..markings import _MarkingsMixin
from ..markings.utils import check_tlp_marking
from ..properties import (
HashesProperty, IDProperty, ListProperty, Property, ReferenceProperty,
SelectorProperty, StringProperty, TimestampProperty, TypeProperty,
)
from ..utils import NOW, _get_dict
def _should_set_millisecond(cr, marking_type):
# TLP instances in the 2.0 spec have millisecond precision unlike other markings
if marking_type == TLPMarking:
return True
# otherwise, precision is kept from how it was given
if isinstance(cr, six.string_types):
if '.' in cr:
return True
else:
return False
if cr.precision == 'millisecond':
return True
return False
class ExternalReference(_STIXBase):
"""For more detailed information on this object's properties, see
`the STIX 2.0 specification <http://docs.oasis-open.org/cti/stix/v2.0/cs01/part1-stix-core/stix-v2.0-cs01-part1-stix-core.html#_Toc496709261>`__.
"""
_properties = OrderedDict([
('source_name', StringProperty(required=True)),
('description', StringProperty()),
('url', StringProperty()),
('hashes', HashesProperty()),
('external_id', StringProperty()),
])
def _check_object_constraints(self):
super(ExternalReference, self)._check_object_constraints()
self._check_at_least_one_property(['description', 'external_id', 'url'])
class KillChainPhase(_STIXBase):
"""For more detailed information on this object's properties, see
`the STIX 2.0 specification <http://docs.oasis-open.org/cti/stix/v2.0/cs01/part1-stix-core/stix-v2.0-cs01-part1-stix-core.html#_Toc496709267>`__.
"""
_properties = OrderedDict([
('kill_chain_name', StringProperty(required=True)),
('phase_name', StringProperty(required=True)),
])
class GranularMarking(_STIXBase):
"""For more detailed information on this object's properties, see
`the STIX 2.0 specification <http://docs.oasis-open.org/cti/stix/v2.0/cs01/part1-stix-core/stix-v2.0-cs01-part1-stix-core.html#_Toc496709290>`__.
"""
_properties = OrderedDict([
('marking_ref', ReferenceProperty(valid_types='marking-definition', spec_version='2.0', required=True)),
('selectors', ListProperty(SelectorProperty, required=True)),
])
class TLPMarking(_STIXBase):
"""For more detailed information on this object's properties, see
`the STIX 2.0 specification <http://docs.oasis-open.org/cti/stix/v2.0/cs01/part1-stix-core/stix-v2.0-cs01-part1-stix-core.html#_Toc496709287>`__.
"""
# TODO: don't allow the creation of any other TLPMarkings than the ones below
_type = 'tlp'
_properties = OrderedDict([
('tlp', StringProperty(required=True)),
])
class StatementMarking(_STIXBase):
"""For more detailed information on this object's properties, see
`the STIX 2.0 specification <http://docs.oasis-open.org/cti/stix/v2.0/cs01/part1-stix-core/stix-v2.0-cs01-part1-stix-core.html#_Toc496709286>`__.
"""
_type = 'statement'
_properties = OrderedDict([
('statement', StringProperty(required=True)),
])
def __init__(self, statement=None, **kwargs):
# Allow statement as positional args.
if statement and not kwargs.get('statement'):
kwargs['statement'] = statement
super(StatementMarking, self).__init__(**kwargs)
class MarkingProperty(Property):
"""Represent the marking objects in the ``definition`` property of
marking-definition objects.
"""
def clean(self, value):
if type(value) in OBJ_MAP_MARKING.values():
return value
else:
raise ValueError("must be a Statement, TLP Marking or a registered marking.")
class MarkingDefinition(_STIXBase, _MarkingsMixin):
"""For more detailed information on this object's properties, see
`the STIX 2.0 specification <http://docs.oasis-open.org/cti/stix/v2.0/cs01/part1-stix-core/stix-v2.0-cs01-part1-stix-core.html#_Toc496709284>`__.
"""
_type = 'marking-definition'
_properties = OrderedDict([
('type', TypeProperty(_type)),
('id', IDProperty(_type, spec_version='2.0')),
('created_by_ref', ReferenceProperty(valid_types='identity', spec_version='2.0')),
('created', TimestampProperty(default=lambda: NOW)),
('external_references', ListProperty(ExternalReference)),
('object_marking_refs', ListProperty(ReferenceProperty(valid_types='marking-definition', spec_version='2.0'))),
('granular_markings', ListProperty(GranularMarking)),
('definition_type', StringProperty(required=True)),
('definition', MarkingProperty(required=True)),
])
def __init__(self, **kwargs):
if set(('definition_type', 'definition')).issubset(kwargs.keys()):
# Create correct marking type object
try:
marking_type = OBJ_MAP_MARKING[kwargs['definition_type']]
except KeyError:
raise ValueError("definition_type must be a valid marking type")
if 'created' in kwargs:
if _should_set_millisecond(kwargs['created'], marking_type):
self._properties = copy.deepcopy(self._properties)
self._properties.update([
('created', TimestampProperty(default=lambda: NOW, precision='millisecond')),
])
if not isinstance(kwargs['definition'], marking_type):
defn = _get_dict(kwargs['definition'])
kwargs['definition'] = marking_type(**defn)
super(MarkingDefinition, self).__init__(**kwargs)
def _check_object_constraints(self):
super(MarkingDefinition, self)._check_object_constraints()
check_tlp_marking(self, '2.0')
def serialize(self, pretty=False, include_optional_defaults=False, **kwargs):
check_tlp_marking(self, '2.0')
return super(MarkingDefinition, self).serialize(pretty, include_optional_defaults, **kwargs)
OBJ_MAP_MARKING = {
'tlp': TLPMarking,
'statement': StatementMarking,
}
def CustomMarking(type='x-custom-marking', properties=None):
"""Custom STIX Marking decorator.
Example:
>>> from stix2 import CustomMarking
>>> from stix2.properties import IntegerProperty, StringProperty
>>> @CustomMarking('x-custom-marking', [
... ('property1', StringProperty(required=True)),
... ('property2', IntegerProperty()),
... ])
... class MyNewMarkingObjectType():
... pass
"""
def wrapper(cls):
return _custom_marking_builder(cls, type, properties, '2.0')
return wrapper
# TODO: don't allow the creation of any other TLPMarkings than the ones below
TLP_WHITE = MarkingDefinition(
id='marking-definition--613f2e26-407d-48c7-9eca-b8e91df99dc9',
created='2017-01-20T00:00:00.000Z',
definition_type='tlp',
definition=TLPMarking(tlp='white'),
)
TLP_GREEN = MarkingDefinition(
id='marking-definition--34098fce-860f-48ae-8e50-ebd3cc5e41da',
created='2017-01-20T00:00:00.000Z',
definition_type='tlp',
definition=TLPMarking(tlp='green'),
)
TLP_AMBER = MarkingDefinition(
id='marking-definition--f88d31f6-486f-44da-b317-01333bde0b82',
created='2017-01-20T00:00:00.000Z',
definition_type='tlp',
definition=TLPMarking(tlp='amber'),
)
TLP_RED = MarkingDefinition(
id='marking-definition--5e57c739-391a-4eb3-b6be-7d15ca92d5ed',
created='2017-01-20T00:00:00.000Z',
definition_type='tlp',
definition=TLPMarking(tlp='red'),
)