PyMISP/examples/feed-generator-from-redis/generator.py

293 lines
10 KiB
Python
Executable File

#!/usr/bin/env python3
import datetime
import hashlib
import json
import os
import sys
import time
import uuid
from pymisp import MISPEvent
import settings
def get_system_templates():
"""Fetch all MISP-Object template present on the local system.
Returns:
dict: A dictionary listing all MISP-Object templates
"""
misp_objects_path = os.path.join(
os.path.abspath(os.path.dirname(sys.modules['pymisp'].__file__)),
'data', 'misp-objects', 'objects')
templates = {}
for root, dirs, files in os.walk(misp_objects_path, topdown=False):
for def_file in files:
obj_name = root.split('/')[-1]
template_path = os.path.join(root, def_file)
with open(template_path, 'r') as f:
definition = json.load(f)
templates[obj_name] = definition
return templates
def gen_uuid():
"""Generate a random UUID and returns its string representation"""
return str(uuid.uuid4())
class FeedGenerator:
"""Helper object to create MISP feed.
Configuration taken from the file settings.py"""
def __init__(self):
"""This object can be use to easily create a daily MISP-feed.
It handles the event creation, manifest file and cache file
(hashes.csv).
"""
self.sys_templates = get_system_templates()
self.constructor_dict = settings.constructor_dict
self.flushing_interval = settings.flushing_interval
self.flushing_next = time.time() + self.flushing_interval
self.manifest = {}
self.attributeHashes = []
self.daily_event_name = settings.daily_event_name + ' {}'
event_date_str, self.current_event_uuid, self.event_name = self.get_last_event_from_manifest()
temp = [int(x) for x in event_date_str.split('-')]
self.current_event_date = datetime.date(temp[0], temp[1], temp[2])
self.current_event = self._get_event_from_id(self.current_event_uuid)
def add_sighting_on_attribute(self, sight_type, attr_uuid, **data):
"""Add a sighting on an attribute.
Not supported for the moment."""
self.update_daily_event_id()
self._after_addition()
return False
def add_attribute_to_event(self, attr_type, attr_value, **attr_data):
"""Add an attribute to the daily event"""
self.update_daily_event_id()
self.current_event.add_attribute(attr_type, attr_value, **attr_data)
self._add_hash(attr_type, attr_value)
self._after_addition()
return True
def add_object_to_event(self, obj_name, **data):
"""Add an object to the daily event"""
self.update_daily_event_id()
if obj_name not in self.sys_templates:
print('Unkown object template')
return False
# Get MISP object constructor
obj_constr = self.constructor_dict.get(obj_name, None)
# Constructor not known, using the generic one
if obj_constr is None:
obj_constr = self.constructor_dict.get('generic')
misp_object = obj_constr(obj_name)
# Fill generic object
for k, v in data.items():
# attribute is not in the object template definition
if k not in self.sys_templates[obj_name]['attributes']:
# add it with type text
misp_object.add_attribute(k, **{'value': v, 'type': 'text'})
else:
misp_object.add_attribute(k, **{'value': v})
else:
misp_object = obj_constr(data)
self.current_event.add_object(misp_object)
for attr_type, attr_value in data.items():
self._add_hash(attr_type, attr_value)
self._after_addition()
return True
def _after_addition(self):
"""Write event on disk"""
now = time.time()
if self.flushing_next <= now:
self.flush_event()
self.flushing_next = now + self.flushing_interval
# Cache
def _add_hash(self, attr_type, attr_value):
if ('|' in attr_type or attr_type == 'malware-sample'):
split = attr_value.split('|')
self.attributeHashes.append([
hashlib.md5(str(split[0]).encode("utf-8")).hexdigest(),
self.current_event_uuid
])
self.attributeHashes.append([
hashlib.md5(str(split[1]).encode("utf-8")).hexdigest(),
self.current_event_uuid
])
else:
self.attributeHashes.append([
hashlib.md5(str(attr_value).encode("utf-8")).hexdigest(),
self.current_event_uuid
])
# Manifest
def _init_manifest(self):
# check if outputdir exists and try to create it if not
if not os.path.exists(settings.outputdir):
try:
os.makedirs(settings.outputdir)
except PermissionError as error:
print(error)
print("Please fix the above error and try again.")
sys.exit(126)
# create an empty manifest
try:
with open(os.path.join(settings.outputdir, 'manifest.json'), 'w'):
pass
except PermissionError as error:
print(error)
print("Please fix the above error and try again.")
sys.exit(126)
# create new event and save manifest
self.create_daily_event()
def flush_event(self, new_event=None):
print('Writting event on disk'+' '*50)
if new_event is not None:
event_uuid = new_event['uuid']
event = new_event
else:
event_uuid = self.current_event_uuid
event = self.current_event
eventFile = open(os.path.join(settings.outputdir, event_uuid+'.json'), 'w')
eventFile.write(event.to_json())
eventFile.close()
self.save_hashes()
def save_manifest(self):
try:
manifestFile = open(os.path.join(settings.outputdir, 'manifest.json'), 'w')
manifestFile.write(json.dumps(self.manifest))
manifestFile.close()
print('Manifest saved')
except Exception as e:
print(e)
sys.exit('Could not create the manifest file.')
def save_hashes(self):
if len(self.attributeHashes) == 0:
return False
try:
hashFile = open(os.path.join(settings.outputdir, 'hashes.csv'), 'a')
for element in self.attributeHashes:
hashFile.write('{},{}\n'.format(element[0], element[1]))
hashFile.close()
self.attributeHashes = []
print('Hash saved' + ' '*30)
except Exception as e:
print(e)
sys.exit('Could not create the quick hash lookup file.')
def _addEventToManifest(self, event):
event_dict = event.to_dict()['Event']
tags = []
for eventTag in event_dict.get('EventTag', []):
tags.append({'name': eventTag['Tag']['name'],
'colour': eventTag['Tag']['colour']})
return {
'Orgc': event_dict.get('Orgc', []),
'Tag': tags,
'info': event_dict['info'],
'date': event_dict['date'],
'analysis': event_dict['analysis'],
'threat_level_id': event_dict['threat_level_id'],
'timestamp': event_dict.get('timestamp', int(time.time()))
}
def get_last_event_from_manifest(self):
"""Retreive last event from the manifest.
If the manifest doesn't exists or if it is empty, initialize it.
"""
try:
manifest_path = os.path.join(settings.outputdir, 'manifest.json')
with open(manifest_path, 'r') as f:
man = json.load(f)
dated_events = []
for event_uuid, event_json in man.items():
# add events to manifest
self.manifest[event_uuid] = event_json
dated_events.append([
event_json['date'],
event_uuid,
event_json['info']
])
# Sort by date then by event name
dated_events.sort(key=lambda k: (k[0], k[2]), reverse=True)
return dated_events[0]
except FileNotFoundError as e:
print('Manifest not found, generating a fresh one')
self._init_manifest()
return self.get_last_event_from_manifest()
# DAILY
def update_daily_event_id(self):
if self.current_event_date != datetime.date.today(): # create new event
# save current event on disk
self.flush_event()
self.current_event = self.create_daily_event()
self.current_event_date = datetime.date.today()
self.current_event_uuid = self.current_event.get('uuid')
self.event_name = self.current_event.info
def _get_event_from_id(self, event_uuid):
with open(os.path.join(settings.outputdir, '%s.json' % event_uuid), 'r') as f:
event_dict = json.load(f)['Event']
event = MISPEvent()
event.from_dict(**event_dict)
return event
def create_daily_event(self):
new_uuid = gen_uuid()
today = str(datetime.date.today())
event_dict = {
'uuid': new_uuid,
'id': len(self.manifest)+1,
'Tag': settings.Tag,
'info': self.daily_event_name.format(today),
'analysis': settings.analysis, # [0-2]
'threat_level_id': settings.threat_level_id, # [1-4]
'published': settings.published,
'date': today
}
event = MISPEvent()
event.from_dict(**event_dict)
# reference org
org_dict = {}
org_dict['name'] = settings.org_name
org_dict['uui'] = settings.org_uuid
event['Orgc'] = org_dict
# save event on disk
self.flush_event(new_event=event)
# add event to manifest
self.manifest[event['uuid']] = self._addEventToManifest(event)
self.save_manifest()
return event