Files
Thomas Nicholson 8d22e9934f Update generate.py
2021-04-29 12:48:12 +01:00

599 lines
27 KiB
Python

#!/usr/bin/python
'''
Generates splunk configurations from manifest files under the security_content repo.
'''
import glob
import yaml
import argparse
from os import path
import sys
import datetime
from jinja2 import Environment, FileSystemLoader
import re
from attackcti import attack_client
import csv
def load_objects(file_path, VERBOSE, REPO_PATH):
files = []
manifest_files = path.join(path.expanduser(REPO_PATH), file_path)
for file in sorted(glob.glob(manifest_files)):
if VERBOSE:
print("processing manifest: {0}".format(file))
files.append(load_file(file))
return files
def load_file(file_path):
with open(file_path, 'r', encoding="utf-8") as stream:
try:
file = list(yaml.safe_load_all(stream))[0]
except yaml.YAMLError as exc:
print(exc)
sys.exit("ERROR: reading {0}".format(file_path))
return file
def generate_transforms_conf(lookups, TEMPLATE_PATH, OUTPUT_PATH):
sorted_lookups = sorted(lookups, key=lambda i: i['name'])
utc_time = datetime.datetime.utcnow().replace(microsecond=0).isoformat()
j2_env = Environment(loader=FileSystemLoader(TEMPLATE_PATH),
trim_blocks=True)
template = j2_env.get_template('transforms.j2')
output_path = path.join(OUTPUT_PATH, 'default/transforms.conf')
output = template.render(lookups=sorted_lookups, time=utc_time)
with open(output_path, 'w', encoding="utf-8") as f:
f.write(output)
return output_path
def generate_collections_conf(lookups, TEMPLATE_PATH, OUTPUT_PATH):
filtered_lookups = list(filter(lambda i: 'collection' in i, lookups))
sorted_lookups = sorted(filtered_lookups, key=lambda i: i['name'])
utc_time = datetime.datetime.utcnow().replace(microsecond=0).isoformat()
j2_env = Environment(loader=FileSystemLoader(TEMPLATE_PATH),
trim_blocks=True)
template = j2_env.get_template('collections.j2')
output_path = path.join(OUTPUT_PATH, 'default/collections.conf')
output = template.render(lookups=sorted_lookups, time=utc_time)
with open(output_path, 'w', encoding="utf-8") as f:
f.write(output)
return output_path
def generate_savedsearches_conf(detections, response_tasks, baselines, deployments, TEMPLATE_PATH, OUTPUT_PATH):
'''
@param detections: input list of individual YAML detections in detections/ directory
@param response_tasks:
@param baselines:
@param deployments:
@return: the savedsearches.conf file located in package/default/
'''
utc_time = datetime.datetime.utcnow().replace(microsecond=0).isoformat()
j2_env = Environment(loader=FileSystemLoader(TEMPLATE_PATH),
trim_blocks=True)
j2_env.filters['custom_jinja2_enrichment_filter'] = custom_jinja2_enrichment_filter
template = j2_env.get_template('savedsearches.j2')
output_path = path.join(OUTPUT_PATH, 'default/savedsearches.conf')
output = template.render(detections=detections, baselines=baselines, response_tasks=response_tasks, time=utc_time)
with open(output_path, 'w') as f:
output = output.encode('ascii', 'ignore').decode('ascii')
f.write(output)
return output_path
def generate_analytic_story_conf(stories, detections, response_tasks, baselines, TEMPLATE_PATH, OUTPUT_PATH):
utc_time = datetime.datetime.utcnow().replace(microsecond=0).isoformat()
j2_env = Environment(loader=FileSystemLoader(TEMPLATE_PATH),
trim_blocks=True)
template = j2_env.get_template('analytic_stories.j2')
output_path = path.join(OUTPUT_PATH, 'default/analytic_stories.conf')
output = template.render(stories=stories, time=utc_time)
with open(output_path, 'w', encoding="utf-8") as f:
f.write(output)
return output_path
def generate_use_case_library_conf(stories, detections, response_tasks, baselines, TEMPLATE_PATH, OUTPUT_PATH):
utc_time = datetime.datetime.utcnow().replace(microsecond=0).isoformat()
j2_env = Environment(loader=FileSystemLoader(TEMPLATE_PATH),
trim_blocks=True)
template = j2_env.get_template('use_case_library.j2')
output_path = path.join(OUTPUT_PATH, 'default/use_case_library.conf')
output = template.render(stories=stories, detections=detections,
response_tasks=response_tasks,
baselines=baselines, time=utc_time)
with open(output_path, 'w', encoding="utf-8") as f:
f.write(output)
return output_path
def generate_macros_conf(macros, detections, TEMPLATE_PATH, OUTPUT_PATH):
filter_macros = []
for detection in detections:
new_dict = {}
new_dict['definition'] = 'search *'
new_dict['description'] = 'Update this macro to limit the output results to filter out false positives. '
new_dict['name'] = detection['name']. \
replace(' ', '_').replace('-', '_').replace('.', '_').replace('/', '_').lower() + '_filter'
filter_macros.append(new_dict)
all_macros = macros + filter_macros
utc_time = datetime.datetime.utcnow().replace(microsecond=0).isoformat()
j2_env = Environment(loader=FileSystemLoader(TEMPLATE_PATH),
trim_blocks=True)
template = j2_env.get_template('macros.j2')
output_path = path.join(OUTPUT_PATH, 'default/macros.conf')
output = template.render(macros=all_macros, time=utc_time)
with open(output_path, 'w', encoding="utf-8") as f:
f.write(output)
return output_path
def generate_workbench_panels(response_tasks, stories, TEMPLATE_PATH, OUTPUT_PATH):
workbench_panel_objects = []
for response_task in response_tasks:
if 'search' in response_task:
if 'inputs' in response_task:
response_file_name = response_task['name'].replace(' ', '_').replace('-','_').replace('.','_').replace('/','_').lower()
response_file_name_xml = response_file_name + "___response_task.xml"
response_task['lowercase_name'] = response_file_name
workbench_panel_objects.append(response_task)
j2_env = Environment(loader=FileSystemLoader(TEMPLATE_PATH),
trim_blocks=True)
template = j2_env.get_template('panel.j2')
file_path = "default/data/ui/panels/workbench_panel_" + response_file_name_xml
output_path = path.join(OUTPUT_PATH, file_path)
response_task['search']= response_task['search'].replace(">",">")
response_task['search']= response_task['search'].replace("<","&lt;")
output = template.render(search=response_task['search'])
with open(output_path, 'w') as f:
f.write(output)
j2_env = Environment(loader=FileSystemLoader(TEMPLATE_PATH),
trim_blocks=True)
template = j2_env.get_template('es_investigations.j2')
output_path = path.join(OUTPUT_PATH, 'default/es_investigations.conf')
output = template.render(response_tasks=workbench_panel_objects, stories=stories)
with open(output_path, 'w', encoding="utf-8") as f:
f.write(output)
j2_env = Environment(loader=FileSystemLoader(TEMPLATE_PATH),
trim_blocks=True)
template = j2_env.get_template('workflow_actions.j2')
output_path = path.join(OUTPUT_PATH, 'default/workflow_actions.conf')
output = template.render(response_tasks=workbench_panel_objects)
with open(output_path, 'w', encoding="utf-8") as f:
f.write(output)
return workbench_panel_objects
def parse_data_models_from_search(search):
match = re.search(r'from\sdatamodel\s?=\s?([^\s.]*)', search)
if match is not None:
return match.group(1)
return False
def parse_author_company(story):
match_author = re.search(r'^([^,]+)', story['author'])
if match_author is None:
match_author = 'no'
else:
match_author = match_author.group(1)
match_company = re.search(r',\s?(.*)$', story['author'])
if match_company is None:
match_company = 'no'
else:
match_company = match_company.group(1)
return match_author, match_company
def get_deployments(object, deployments):
matched_deployments = []
for deployment in deployments:
for tag in object['tags'].keys():
if tag in deployment['tags'].keys():
if type(object['tags'][tag]) is str:
tag_array = [object['tags'][tag]]
else:
tag_array = object['tags'][tag]
for tag_value in tag_array:
if type(deployment['tags'][tag]) is str:
tag_array_deployment = [deployment['tags'][tag]]
else:
tag_array_deployment = deployment['tags'][tag]
for tag_value_deployment in tag_array_deployment:
if tag_value == tag_value_deployment:
# print("tag value: {}, matched deployment tag: {} on deployment: {}".format(tag_value,tag_value_deployment, deployment))
matched_deployments.append(deployment)
continue
# grab default for all stories if deployment not set
if len(matched_deployments) == 0:
for deployment in deployments:
if 'analytic_story' in deployment['tags']:
if deployment['tags']['analytic_story'] == 'all':
last_deployment = deployment
else:
last_deployment = matched_deployments[-1]
# last_deployment = replace_vars_in_deployment(last_deployment, object) # Not needed because of custom_jinja2_enrichment_filter
# print(last_deployment)
return last_deployment
def get_nes_fields(search, deployment):
nes_fields_matches = []
if 'alert_action' in deployment:
if 'notable' in deployment['alert_action']:
if 'nes_fields' in deployment['alert_action']['notable']:
for field in deployment['alert_action']['notable']['nes_fields']:
if (search.find(field + ' ') != -1):
nes_fields_matches.append(field)
return nes_fields_matches
def map_response_tasks_to_stories(response_tasks):
sto_res = {}
for response_task in response_tasks:
if 'tags' in response_task:
if 'analytic_story' in response_task['tags']:
for story in response_task['tags']['analytic_story']:
if 'type' in response_task.keys():
if response_task['type'] == 'response':
task_name = str('ESCU - ' + response_task['name'] + ' - Response Task')
else:
task_name = str('ESCU - ' + response_task['name'] + ' - Response Task')
if not (story in sto_res):
sto_res[story] = {task_name}
else:
sto_res[story].add(task_name)
return sto_res
def map_baselines_to_stories(baselines):
sto_bas = {}
for baseline in baselines:
if 'tags' in baseline:
if 'analytic_story' in baseline['tags']:
for story in baseline['tags']['analytic_story']:
if 'type' in baseline.keys():
if baseline['type'] == 'batch':
baseline_name = str('ESCU - ' + baseline['name'])
else:
baseline_name = str('ESCU - ' + baseline['name'])
if not (story in sto_bas):
sto_bas[story] = {baseline_name}
else:
sto_bas[story].add(baseline_name)
return sto_bas
def custom_jinja2_enrichment_filter(string, object):
customized_string = string
for key in object.keys():
[key.encode('utf-8') for key in object]
customized_string = customized_string.replace("%" + key + "%", str(object[key]))
for key in object['tags'].keys():
customized_string = customized_string.replace("%" + key + "%", str(object['tags'][key]))
return customized_string
def prepare_detections(detections, deployments, OUTPUT_PATH):
for detection in detections:
# parse out data_models
data_model = parse_data_models_from_search(detection['search'])
if data_model:
detection['data_model'] = data_model
matched_deployment = get_deployments(detection, deployments)
detection['deployment'] = matched_deployment
nes_fields = get_nes_fields(detection['search'], detection['deployment'])
if len(nes_fields) > 0:
detection['nes_fields'] = nes_fields
keys = ['mitre_attack', 'kill_chain_phases', 'cis20', 'nist']
mappings = {}
for key in keys:
if key == 'mitre_attack':
if 'mitre_attack_id' in detection['tags']:
mappings[key] = detection['tags']['mitre_attack_id']
else:
if key in detection['tags']:
mappings[key] = detection['tags'][key]
detection['mappings'] = mappings
# used for upstream processing of risk scoring annotations in ECSU
# this is not currently compatible with newer instances of ESCU (6.3.0+)
# we are duplicating the code block above for now and just changing variable names to make future
# changes to this data structure separate from the mappings generation
# @todo expose the JSON data structure for newer risk type
annotation_keys = ['mitre_attack', 'kill_chain_phases', 'cis20', 'nist', 'analytic_story']
savedsearch_annotations = {}
for key in annotation_keys:
if key == 'mitre_attack':
if 'mitre_attack_id' in detection['tags']:
savedsearch_annotations[key] = detection['tags']['mitre_attack_id']
else:
if key in detection['tags']:
savedsearch_annotations[key] = detection['tags'][key]
detection['savedsearch_annotations'] = savedsearch_annotations
if 'risk_object' in detection['tags']:
detection['risk_object'] = detection['tags']['risk_object']
if 'risk_object_type' in detection['tags']:
detection['risk_object_type'] = detection['tags']['risk_object_type']
if 'risk_score' in detection['tags']:
detection['risk_score'] = detection['tags']['risk_score']
if 'product' in detection['tags']:
detection['product'] = detection['tags']['product']
if (OUTPUT_PATH) == 'dist/saaws':
detection['disabled'] = 'false'
return detections
def prepare_baselines(baselines, deployments, OUTPUT_PATH):
for baseline in baselines:
data_model = parse_data_models_from_search(baseline['search'])
if data_model:
baseline['data_model'] = data_model
if (OUTPUT_PATH) == 'dist/saaws':
baseline['disabled'] = 'false'
matched_deployment = get_deployments(baseline, deployments)
baseline['deployment'] = matched_deployment
return baselines
def prepare_response_tasks(response_tasks):
for response_task in response_tasks:
if 'search' in response_task:
data_model = parse_data_models_from_search(response_task['search'])
if data_model:
response_task['data_model'] = data_model
return response_tasks
def prepare_stories(stories, detections, response_tasks, baselines):
# enrich stories with information from detections: data_models, mitre_ids, kill_chain_phases, nists
sto_to_data_models = {}
sto_to_mitre_attack_ids = {}
sto_to_kill_chain_phases = {}
sto_to_ciss = {}
sto_to_nists = {}
sto_to_det = {}
for detection in detections:
if 'analytic_story' in detection['tags']:
for story in detection['tags']['analytic_story']:
if 'type' in detection.keys():
if detection['type'] == 'batch':
rule_name = str('ESCU - ' + detection['name'] + ' - Rule')
else:
rule_name = str('ESCU - ' + detection['name'] + ' - Rule')
if story in sto_to_det.keys():
sto_to_det[story].add(rule_name)
else:
sto_to_det[story] = {rule_name}
data_model = parse_data_models_from_search(detection['search'])
if data_model:
if story in sto_to_data_models.keys():
sto_to_data_models[story].add(data_model)
else:
sto_to_data_models[story] = {data_model}
if 'mitre_attack_id' in detection['tags']:
if story in sto_to_mitre_attack_ids.keys():
for mitre_attack_id in detection['tags']['mitre_attack_id']:
sto_to_mitre_attack_ids[story].add(mitre_attack_id)
else:
sto_to_mitre_attack_ids[story] = set(detection['tags']['mitre_attack_id'])
if 'kill_chain_phases' in detection['tags']:
if story in sto_to_kill_chain_phases.keys():
for kill_chain in detection['tags']['kill_chain_phases']:
sto_to_kill_chain_phases[story].add(kill_chain)
else:
sto_to_kill_chain_phases[story] = set(detection['tags']['kill_chain_phases'])
if 'cis20' in detection['tags']:
if story in sto_to_ciss.keys():
for cis in detection['tags']['cis20']:
sto_to_ciss[story].add(cis)
else:
sto_to_ciss[story] = set(detection['tags']['cis20'])
if 'nist' in detection['tags']:
if story in sto_to_nists.keys():
for nist in detection['tags']['nist']:
sto_to_nists[story].add(nist)
else:
sto_to_nists[story] = set(detection['tags']['nist'])
sto_res = map_response_tasks_to_stories(response_tasks)
sto_bas = map_baselines_to_stories(baselines)
for story in stories:
story['author_name'], story['author_company'] = parse_author_company(story)
story['lowercase_name'] = story['name'].replace(' ', '_').replace('-','_').replace('.','_').replace('/','_').lower()
story['detections'] = sorted(sto_to_det[story['name']])
story['searches'] = story['detections']
if story['name'] in sto_to_data_models:
story['data_models'] = sorted(sto_to_data_models[story['name']])
if story['name'] in sto_to_mitre_attack_ids:
story['mitre_attack'] = sorted(sto_to_mitre_attack_ids[story['name']])
if story['name'] in sto_to_kill_chain_phases:
story['kill_chain_phases'] = sorted(sto_to_kill_chain_phases[story['name']])
if story['name'] in sto_to_ciss:
story['cis20'] = sorted(sto_to_ciss[story['name']])
if story['name'] in sto_to_nists:
story['nist'] = sorted(sto_to_nists[story['name']])
if story['name'] in sto_res:
story['response_tasks'] = sorted(list(sto_res[story['name']]))
story['searches'] = story['searches'] + story['response_tasks']
story['workbench_panels'] = []
for response_task_name in story['response_tasks']:
s = 'panel://workbench_panel_' + response_task_name[7:].replace(' ', '_').replace('-','_').replace('.','_').replace('/','_').lower()
story['workbench_panels'].append(s)
if story['name'] in sto_bas:
story['baselines'] = sorted(list(sto_bas[story['name']]))
keys = ['mitre_attack', 'kill_chain_phases', 'cis20', 'nist']
mappings = {}
for key in keys:
if key in story:
mappings[key] = story[key]
story['mappings'] = mappings
return stories
def generate_mitre_lookup(OUTPUT_PATH):
csv_mitre_rows = [["mitre_id", "technique", "tactics", "groups"]]
lift = attack_client()
all_enterprise = lift.get_enterprise(stix_format=False)
enterprise_relationships = lift.get_enterprise_relationships()
enterprise_groups = lift.get_enterprise_groups()
for technique in all_enterprise['techniques']:
apt_groups = []
for relationship in enterprise_relationships:
if (relationship['target_ref'] == technique['id']) and relationship['source_ref'].startswith('intrusion-set'):
for group in enterprise_groups:
if relationship['source_ref'] == group['id']:
apt_groups.append(group['name'])
if not ('revoked' in technique):
if len(apt_groups) == 0:
apt_groups.append('no')
csv_mitre_rows.append([technique['technique_id'], technique['technique'], '|'.join(technique['tactic']).replace('-',' ').title(), '|'.join(apt_groups)])
with open(path.join(OUTPUT_PATH, 'lookups/mitre_enrichment.csv'), 'w', newline='', encoding="utf-8") as file:
writer = csv.writer(file)
writer.writerows(csv_mitre_rows)
def import_objects(VERBOSE, REPO_PATH):
objects = {
"stories": load_objects("stories/*.yml", VERBOSE, REPO_PATH),
"macros": load_objects("macros/*.yml", VERBOSE, REPO_PATH),
"lookups": load_objects("lookups/*.yml", VERBOSE, REPO_PATH),
"baselines": load_objects("baselines/*.yml", VERBOSE, REPO_PATH),
"responses": load_objects("responses/*.yml", VERBOSE, REPO_PATH),
"response_tasks": load_objects("response_tasks/*.yml", VERBOSE, REPO_PATH),
"deployments": load_objects("deployments/*.yml", VERBOSE, REPO_PATH),
"detections": load_objects("detections/*/*.yml", VERBOSE, REPO_PATH),
}
objects["detections"].extend(load_objects("detections/*/*/*.yml", VERBOSE, REPO_PATH))
return objects
def compute_objects(objects, PRODUCT, OUTPUT_PATH):
if PRODUCT == "SAAWS":
objects["detections"] = [object for object in objects["detections"] if 'Splunk Security Analytics for AWS' in object['tags']['product']]
objects["stories"] = [object for object in objects["stories"] if 'Splunk Security Analytics for AWS' in object['tags']['product']]
objects["baselines"] = [object for object in objects["baselines"] if 'Splunk Security Analytics for AWS' in object['tags']['product']]
objects["response_tasks"] = [object for object in objects["response_tasks"] if 'Splunk Security Analytics for AWS' in object['tags']['product']]
# only use ESCU detections to the configurations
objects["detections"] = sorted(filter(lambda d: d['type'].lower() == 'batch', objects["detections"]), key=lambda d: d['name'])
# only use ESCU stories to the configuration
objects["stories"] = sorted(filter(lambda s: s['type'].lower() == 'batch', objects["stories"]), key=lambda s: s['name'])
objects["response_tasks"] = sorted(objects["response_tasks"], key=lambda i: i['name'])
objects["baselines"] = sorted(objects["baselines"], key=lambda b: b['name'])
objects["macros"] = sorted(objects["macros"], key=lambda m: m['name'])
objects["detections"] = prepare_detections(objects["detections"], objects["deployments"], OUTPUT_PATH)
objects["baselines"] = prepare_baselines(objects["baselines"], objects["deployments"], OUTPUT_PATH)
objects["response_tasks"] = prepare_response_tasks(objects["response_tasks"])
objects["stories"] = prepare_stories(objects["stories"], objects["detections"], objects["response_tasks"], objects["baselines"])
return objects
def get_objects(REPO_PATH, OUTPUT_PATH, PRODUCT, VERBOSE):
objects = import_objects(VERBOSE, REPO_PATH)
objects = compute_objects(objects, PRODUCT, OUTPUT_PATH)
return objects
def main(REPO_PATH, OUTPUT_PATH, PRODUCT, VERBOSE):
TEMPLATE_PATH = path.join(REPO_PATH, 'bin/jinja2_templates')
objects = get_objects(REPO_PATH, OUTPUT_PATH, PRODUCT, VERBOSE)
try:
if VERBOSE:
print("generating Mitre lookups")
generate_mitre_lookup(OUTPUT_PATH)
except Exception as e:
print('Error: ' + str(e))
print("WARNING: Generation of Mitre lookup failed.")
lookups_path = generate_transforms_conf(objects["lookups"], TEMPLATE_PATH, OUTPUT_PATH)
lookups_path = generate_collections_conf(objects["lookups"], TEMPLATE_PATH, OUTPUT_PATH)
detection_path = generate_savedsearches_conf(objects["detections"], objects["response_tasks"], objects["baselines"], objects["deployments"], TEMPLATE_PATH, OUTPUT_PATH)
story_path = generate_analytic_story_conf(objects["stories"], objects["detections"], objects["response_tasks"], objects["baselines"], TEMPLATE_PATH, OUTPUT_PATH)
use_case_lib_path = generate_use_case_library_conf(objects["stories"], objects["detections"], objects["response_tasks"], objects["baselines"], TEMPLATE_PATH, OUTPUT_PATH)
macros_path = generate_macros_conf(objects["macros"], objects["detections"], TEMPLATE_PATH, OUTPUT_PATH)
workbench_panels_objects = generate_workbench_panels(objects["response_tasks"], objects["stories"], TEMPLATE_PATH, OUTPUT_PATH)
if VERBOSE:
print("{0} stories have been successfully written to {1}".format(len(objects["stories"]), story_path))
print("{0} detections have been successfully written to {1}".format(len(objects["detections"]), detection_path))
print("{0} response tasks have been successfully written to {1}".format(len(objects["response_tasks"]), detection_path))
print("{0} baselines have been successfully written to {1}".format(len(objects["baselines"]), detection_path))
print("{0} macros have been successfully written to {1}".format(len(objects["macros"]), macros_path))
print("{0} workbench panels have been successfully written to {1}, {2} and {3}".format(len(workbench_panels_objects), OUTPUT_PATH + "/default/es_investigations.conf", OUTPUT_PATH + "/default/workflow_actions.conf", OUTPUT_PATH + "/default/data/ui/panels/*"))
print("security content generation completed..")
if __name__ == "__main__":
parser = argparse.ArgumentParser(description="generates splunk conf files out of security_content manifests", epilog="""
This tool converts manifests to the source files to be used by products like Splunk Enterprise.
It generates the savesearches.conf, analytics_stories.conf files for ES.""")
parser.add_argument("-p", "--path", required=True, help="path to security_content repo")
parser.add_argument("-o", "--output", required=True, help="path to the output directory")
parser.add_argument("-v", "--verbose", required=False, default=False, action='store_true', help="prints verbose output")
parser.add_argument("--product", required=True, default="ESCU", help="package type")
# parse them
args = parser.parse_args()
REPO_PATH = args.path
OUTPUT_PATH = args.output
VERBOSE = args.verbose
PRODUCT = args.product
main(REPO_PATH, OUTPUT_PATH, PRODUCT, VERBOSE)