267 lines
8.2 KiB
Python
267 lines
8.2 KiB
Python
import collections
|
|
from datetime import datetime
|
|
import json
|
|
import uuid
|
|
|
|
import pytz
|
|
|
|
|
|
def format_datetime(dt):
|
|
# TODO: how to handle naive datetime
|
|
|
|
# 1. Convert to UTC
|
|
# 2. Format in isoformat
|
|
# 3. Strip off "+00:00"
|
|
# 4. Add "Z"
|
|
|
|
# TODO: how to handle timestamps with subsecond 0's
|
|
return dt.astimezone(pytz.utc).isoformat()[:-6] + "Z"
|
|
|
|
|
|
class _STIXBase(collections.Mapping):
|
|
"""Base class for STIX object types"""
|
|
|
|
def __getitem__(self, key):
|
|
return self._inner[key]
|
|
|
|
def __iter__(self):
|
|
return iter(self._inner)
|
|
|
|
def __len__(self):
|
|
return len(self._inner)
|
|
|
|
# Handle attribute access just like key access
|
|
def __getattr__(self, name):
|
|
return self.get(name)
|
|
|
|
def __setattr__(self, name, value):
|
|
if name != '_inner':
|
|
raise ValueError("Cannot modify properties after creation.")
|
|
super(_STIXBase, self).__setattr__(name, value)
|
|
|
|
def __str__(self):
|
|
# TODO: put keys in specific order. Probably need custom JSON encoder.
|
|
return json.dumps(self._dict(), indent=4, sort_keys=True,
|
|
separators=(",", ": ")) # Don't include spaces after commas.
|
|
|
|
|
|
class Indicator(_STIXBase):
|
|
|
|
_properties = [
|
|
'type',
|
|
'id',
|
|
'created',
|
|
'modified',
|
|
'labels',
|
|
'pattern',
|
|
'valid_from',
|
|
]
|
|
|
|
def __init__(self, **kwargs):
|
|
# TODO:
|
|
# - created_by_ref
|
|
# - revoked
|
|
# - external_references
|
|
# - object_marking_refs
|
|
# - granular_markings
|
|
|
|
# - name
|
|
# - description
|
|
# - valid_until
|
|
# - kill_chain_phases
|
|
|
|
# TODO: do we care about the performance penalty of creating this
|
|
# if we won't need it?
|
|
now = datetime.now(tz=pytz.UTC)
|
|
|
|
if not kwargs.get('type'):
|
|
kwargs['type'] = 'indicator'
|
|
if kwargs['type'] != 'indicator':
|
|
raise ValueError("Indicator must have type='indicator'.")
|
|
|
|
if not kwargs.get('id'):
|
|
kwargs['id'] = 'indicator--' + str(uuid.uuid4())
|
|
if not kwargs['id'].startswith('indicator--'):
|
|
raise ValueError("Indicator id values must begin with 'indicator--'.")
|
|
|
|
if not kwargs.get('labels'):
|
|
raise ValueError("Missing required field for Indicator: 'labels'.")
|
|
|
|
if not kwargs.get('pattern'):
|
|
raise ValueError("Missing required field for Indicator: 'pattern'.")
|
|
|
|
extra_kwargs = list(set(kwargs.keys()) - set(self._properties))
|
|
if extra_kwargs:
|
|
raise TypeError("unexpected keyword arguments: " + str(extra_kwargs))
|
|
|
|
self._inner = {
|
|
'type': kwargs['type'],
|
|
'id': kwargs['id'],
|
|
'created': kwargs.get('created', now),
|
|
'modified': kwargs.get('modified', now),
|
|
'labels': kwargs['labels'],
|
|
'pattern': kwargs['pattern'],
|
|
'valid_from': kwargs.get('valid_from', now),
|
|
}
|
|
|
|
def _dict(self):
|
|
return {
|
|
'type': self['type'],
|
|
'id': self['id'],
|
|
'created': format_datetime(self['created']),
|
|
'modified': format_datetime(self['modified']),
|
|
'labels': self['labels'],
|
|
'pattern': self['pattern'],
|
|
'valid_from': format_datetime(self['valid_from']),
|
|
}
|
|
|
|
|
|
class Malware(_STIXBase):
|
|
|
|
_properties = [
|
|
'type',
|
|
'id',
|
|
'created',
|
|
'modified',
|
|
'labels',
|
|
'name',
|
|
]
|
|
|
|
def __init__(self, **kwargs):
|
|
# TODO:
|
|
# - created_by_ref
|
|
# - revoked
|
|
# - external_references
|
|
# - object_marking_refs
|
|
# - granular_markings
|
|
|
|
# - description
|
|
# - kill_chain_phases
|
|
|
|
# TODO: do we care about the performance penalty of creating this
|
|
# if we won't need it?
|
|
now = datetime.now(tz=pytz.UTC)
|
|
|
|
if not kwargs.get('type'):
|
|
kwargs['type'] = 'malware'
|
|
if kwargs['type'] != 'malware':
|
|
raise ValueError("Malware must have type='malware'.")
|
|
|
|
if not kwargs.get('id'):
|
|
kwargs['id'] = 'malware--' + str(uuid.uuid4())
|
|
if not kwargs['id'].startswith('malware--'):
|
|
raise ValueError("Malware id values must begin with 'malware--'.")
|
|
|
|
if not kwargs.get('labels'):
|
|
raise ValueError("Missing required field for Malware: 'labels'.")
|
|
|
|
if not kwargs.get('name'):
|
|
raise ValueError("Missing required field for Malware: 'name'.")
|
|
|
|
extra_kwargs = list(set(kwargs.keys()) - set(self._properties))
|
|
if extra_kwargs:
|
|
raise TypeError("unexpected keyword arguments: " + str(extra_kwargs))
|
|
|
|
self._inner = {
|
|
'type': kwargs['type'],
|
|
'id': kwargs['id'],
|
|
'created': kwargs.get('created', now),
|
|
'modified': kwargs.get('modified', now),
|
|
'labels': kwargs['labels'],
|
|
'name': kwargs['name'],
|
|
}
|
|
|
|
def _dict(self):
|
|
return {
|
|
'type': self['type'],
|
|
'id': self['id'],
|
|
'created': format_datetime(self['created']),
|
|
'modified': format_datetime(self['modified']),
|
|
'labels': self['labels'],
|
|
'name': self['name'],
|
|
}
|
|
|
|
|
|
class Relationship(_STIXBase):
|
|
|
|
_properties = [
|
|
'type',
|
|
'id',
|
|
'created',
|
|
'modified',
|
|
'relationship_type',
|
|
'source_ref',
|
|
'target_ref',
|
|
]
|
|
|
|
# Explicitly define the first three kwargs to make readable Relationship declarations.
|
|
def __init__(self, source_ref=None, relationship_type=None, target_ref=None,
|
|
**kwargs):
|
|
# TODO:
|
|
# - created_by_ref
|
|
# - revoked
|
|
# - external_references
|
|
# - object_marking_refs
|
|
# - granular_markings
|
|
|
|
# - description
|
|
|
|
if source_ref and not kwargs.get('source_ref'):
|
|
kwargs['source_ref'] = source_ref
|
|
if relationship_type and not kwargs.get('relationship_type'):
|
|
kwargs['relationship_type'] = relationship_type
|
|
if target_ref and not kwargs.get('target_ref'):
|
|
kwargs['target_ref'] = target_ref
|
|
|
|
# TODO: do we care about the performance penalty of creating this
|
|
# if we won't need it?
|
|
now = datetime.now(tz=pytz.UTC)
|
|
|
|
if not kwargs.get('type'):
|
|
kwargs['type'] = 'relationship'
|
|
if kwargs['type'] != 'relationship':
|
|
raise ValueError("Relationship must have type='relationship'.")
|
|
|
|
if not kwargs.get('id'):
|
|
kwargs['id'] = 'relationship--' + str(uuid.uuid4())
|
|
if not kwargs['id'].startswith('relationship--'):
|
|
raise ValueError("Relationship id values must begin with 'relationship--'.")
|
|
|
|
if not kwargs.get('relationship_type'):
|
|
raise ValueError("Missing required field for Relationship: 'relationship_type'.")
|
|
|
|
if not kwargs.get('source_ref'):
|
|
raise ValueError("Missing required field for Relationship: 'source_ref'.")
|
|
elif isinstance(kwargs['source_ref'], _STIXBase):
|
|
kwargs['source_ref'] = kwargs['source_ref'].id
|
|
|
|
if not kwargs.get('target_ref'):
|
|
raise ValueError("Missing required field for Relationship: 'target_ref'.")
|
|
elif isinstance(kwargs['target_ref'], _STIXBase):
|
|
kwargs['target_ref'] = kwargs['target_ref'].id
|
|
|
|
extra_kwargs = list(set(kwargs.keys()) - set(self._properties))
|
|
if extra_kwargs:
|
|
raise TypeError("unexpected keyword arguments: " + str(extra_kwargs))
|
|
|
|
self._inner = {
|
|
'type': kwargs['type'],
|
|
'id': kwargs['id'],
|
|
'created': kwargs.get('created', now),
|
|
'modified': kwargs.get('modified', now),
|
|
'relationship_type': kwargs['relationship_type'],
|
|
'source_ref': kwargs['source_ref'],
|
|
'target_ref': kwargs['target_ref'],
|
|
}
|
|
|
|
def _dict(self):
|
|
return {
|
|
'type': self['type'],
|
|
'id': self['id'],
|
|
'created': format_datetime(self['created']),
|
|
'modified': format_datetime(self['modified']),
|
|
'relationship_type': self['relationship_type'],
|
|
'source_ref': self['source_ref'],
|
|
'target_ref': self['target_ref'],
|
|
}
|