misp-warninglists/tools/generate_mozilla_certificates.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import csv
import datetime
import json
from inspect import currentframe, getframeinfo
from os import path

import requests
from OpenSSL.crypto import FILETYPE_PEM, load_certificate


def download(url, file):
    r = requests.get(url)
    with open(file, 'wb') as fd:
        for chunk in r.iter_content(4096):
            fd.write(chunk)


def gethash(cert, digest):
    return cert.digest(digest).decode('ASCII').replace(':', '').lower()


def get_abspath_list_file(dst):
    rel_path = getframeinfo(currentframe()).filename
    current_folder = path.dirname(path.abspath(rel_path))
    real_path = path.join(
        current_folder, '../lists/{dst}/list.json'.format(dst=dst))
    return path.abspath(path.realpath(real_path))


def process(file, dst, type):
    hashes = set()
    with open(file, 'r') as f_in:
        for obj in csv.DictReader(f_in):
            pem = obj['PEM Info'].strip("'").replace(
                '\r', '').replace('\n\n', '\n')
            try:
                obj['Certificate Name']
            except:
                obj['Common Name or Certificate Name']
            cert = load_certificate(FILETYPE_PEM, pem)
            hashes.add(gethash(cert, 'md5'))
            hashes.add(gethash(cert, 'sha1'))
            hashes.add(obj['SHA-256 Fingerprint'].lower())

    warninglist = {}
    warninglist['name'] = 'Fingerprint of {type}'.format(type=type)
    warninglist['version'] = int(datetime.date.today().strftime('%Y%m%d'))
    warninglist['description'] = "Fingerprint of {type} taken from Mozilla's lists at https://wiki.mozilla.org/CA".format(
        type=type)
    warninglist['list'] = sorted(hashes)
    warninglist['type'] = 'string'
    warninglist['matching_attributes'] = ["md5", "sha1", "sha256", "filename|md5", "filename|sha1",
                                          "filename|sha256", "x509-fingerprint-md5", "x509-fingerprint-sha1", "x509-fingerprint-sha256"]

    with open(get_abspath_list_file(dst), 'w') as data_file:
        json.dump(warninglist, data_file, indent=2, sort_keys=True)
        data_file.write("\n")


if __name__ == '__main__':
    Included_CA_url = 'https://ccadb-public.secure.force.com/mozilla/IncludedCACertificateReportPEMCSV'
    Included_CA_file = 'IncludedCACertificateReportPEMCSV.csv'
    Included_CA_dst = 'mozilla-CA'
    CA_known_intermediate_url = 'https://ccadb-public.secure.force.com/mozilla/PublicAllIntermediateCertsWithPEMCSV'
    CA_known_intermediate_file = 'PublicAllIntermediateCertsWithPEMCSV.csv'
    CA_known_intermediate_dst = 'mozilla-IntermediateCA'

    download(Included_CA_url, Included_CA_file)
    process(Included_CA_file, Included_CA_dst, 'trusted CA certificates')
    download(CA_known_intermediate_url, CA_known_intermediate_file)
    process(CA_known_intermediate_file, CA_known_intermediate_dst,
            'known intermedicate of trusted certificates')