PyMISP/pymisp/abstract.py

234 lines
7.8 KiB
Python

#!/usr/bin/env python
# -*- coding: utf-8 -*-
import abc
import sys
import datetime
import json
from json import JSONEncoder
import collections
import six # Remove that import when discarding python2 support.
import logging
from .exceptions import PyMISPInvalidFormat
logger = logging.getLogger('pymisp')
if six.PY2:
logger.warning("You're using python 2, it is strongly recommended to use python >=3.5")
# This is required because Python 2 is a pain.
from datetime import tzinfo, timedelta
class UTC(tzinfo):
"""UTC"""
def utcoffset(self, dt):
return timedelta(0)
def tzname(self, dt):
return "UTC"
def dst(self, dt):
return timedelta(0)
class MISPEncode(JSONEncoder):
def default(self, obj):
if isinstance(obj, AbstractMISP):
return obj.jsonable()
elif isinstance(obj, datetime.datetime):
return obj.isoformat()
return JSONEncoder.default(self, obj)
@six.add_metaclass(abc.ABCMeta) # Remove that line when discarding python2 support.
class AbstractMISP(collections.MutableMapping):
__not_jsonable = []
def __init__(self, **kwargs):
"""Abstract class for all the MISP objects"""
super(AbstractMISP, self).__init__()
self.__edited = True # As we create a new object, we assume it is edited
# List of classes having tags
from .mispevent import MISPAttribute, MISPEvent
self.__has_tags = (MISPAttribute, MISPEvent)
if isinstance(self, self.__has_tags):
self.Tag = []
setattr(AbstractMISP, 'add_tag', AbstractMISP.__add_tag)
setattr(AbstractMISP, 'tags', property(AbstractMISP.__get_tags, AbstractMISP.__set_tags))
@property
def properties(self):
"""All the class public properties that will be dumped in the dictionary, and the JSON export.
Note: all the properties starting with a `_` (private), or listed in __not_jsonable will be skipped.
"""
to_return = []
for prop, value in vars(self).items():
if prop.startswith('_') or prop in self.__not_jsonable:
continue
to_return.append(prop)
return to_return
def from_dict(self, **kwargs):
"""Loading all the parameters as class properties, if they aren't `None`.
This method aims to be called when all the properties requiring a special
treatment are processed.
Note: This method is used when you initialize an object with existing data so by default,
the class is flaged as not edited."""
for prop, value in kwargs.items():
if value is None:
continue
setattr(self, prop, value)
# We load an existing dictionary, marking it an not-edited
self.__edited = False
def update_not_jsonable(self, *args):
"""Add entries to the __not_jsonable list"""
self.__not_jsonable += args
def set_not_jsonable(self, *args):
"""Set __not_jsonable to a new list"""
self.__not_jsonable = args
def from_json(self, json_string):
"""Load a JSON string"""
self.from_dict(**json.loads(json_string))
def to_dict(self):
"""Dump the lass to a dictionary.
This method automatically removes the timestamp recursively in every object
that has been edited is order to let MISP update the event accordingly."""
to_return = {}
for attribute in self.properties:
val = getattr(self, attribute, None)
if val is None:
continue
elif isinstance(val, list) and len(val) == 0:
continue
if attribute == 'timestamp':
if self.edited:
# In order to be accepted by MISP, the timestamp of an object
# needs to be either newer, or None.
# If the current object is marked as edited, the easiest is to
# skip the timestamp and let MISP deal with it
continue
else:
val = self._datetime_to_timestamp(val)
to_return[attribute] = val
return to_return
def jsonable(self):
"""This method is used by the JSON encoder"""
return self.to_dict()
def to_json(self):
"""Dump recursively any class of type MISPAbstract to a json string"""
return json.dumps(self, cls=MISPEncode, sort_keys=True, indent=2)
def __getitem__(self, key):
try:
return getattr(self, key)
except AttributeError:
# Expected by pop and other dict-related methods
raise KeyError
def __setitem__(self, key, value):
setattr(self, key, value)
def __delitem__(self, key):
delattr(self, key)
def __iter__(self):
return iter(self.to_dict())
def __len__(self):
return len(self.to_dict())
@property
def edited(self):
"""Recursively check if an object has been edited and update the flag accordingly
to the parent objects"""
if self.__edited:
return self.__edited
for p in self.properties:
if self.__edited:
break
val = getattr(self, p)
if isinstance(val, AbstractMISP) and val.edited:
self.__edited = True
elif isinstance(val, list) and all(isinstance(a, AbstractMISP) for a in val):
if any(a.edited for a in val):
self.__edited = True
return self.__edited
@edited.setter
def edited(self, val):
"""Set the edit flag"""
if isinstance(val, bool):
self.__edited = val
else:
raise Exception('edited can only be True or False')
def __setattr__(self, name, value):
if name in self.properties:
self.__edited = True
super(AbstractMISP, self).__setattr__(name, value)
def _datetime_to_timestamp(self, d):
"""Convert a datetime.datetime object to a timestamp (int)"""
if isinstance(d, (int, str)) or (sys.version_info < (3, 0) and isinstance(d, unicode)):
# Assume we already have a timestamp
return d
if sys.version_info >= (3, 3):
return int(d.timestamp())
else:
return int((d - datetime.datetime.fromtimestamp(0, UTC())).total_seconds())
def __add_tag(self, tag=None, **kwargs):
"""Add a tag to the attribute (by name or a MISPTag object)"""
if isinstance(tag, str):
misp_tag = MISPTag()
misp_tag.from_dict(name=tag)
elif isinstance(tag, MISPTag):
misp_tag = tag
elif isinstance(tag, dict):
misp_tag = MISPTag()
misp_tag.from_dict(**tag)
elif kwargs:
misp_tag = MISPTag()
misp_tag.from_dict(**kwargs)
else:
raise PyMISPInvalidFormat("The tag is in an invalid format (can be either string, MISPTag, or an expanded dict): {}".format(tag))
self.Tag.append(misp_tag)
self.edited = True
def __get_tags(self):
"""Returns a lost of tags associated to this Attribute"""
return self.Tag
def __set_tags(self, tags):
"""Set a list of prepared MISPTag."""
if all(isinstance(x, MISPTag) for x in tags):
self.Tag = tags
else:
raise PyMISPInvalidFormat('All the attributes have to be of type MISPTag.')
class MISPTag(AbstractMISP):
def __init__(self):
super(MISPTag, self).__init__()
def from_dict(self, name, **kwargs):
self.name = name
super(MISPTag, self).from_dict(**kwargs)
def __repr__(self):
if hasattr(self, 'name'):
return '<{self.__class__.__name__}(name={self.name})'.format(self=self)
return '<{self.__class__.__name__}(NotInitialized)'.format(self=self)