ssl_cert_inspector.py

#!/usr/bin/env python

import argparse, datetime, subprocess, sys, ssl, socket, logging, pprint

# Get CLI values and set logging level
class CLI(object):
  def __init__(self):
    parser = argparse.ArgumentParser()
    parser.add_argument('-i', action='store', default="google.com", dest='host',
                        help='inspect the following target to check ssl.')
    parser.add_argument('-p', action='store', default=443, dest='port', help='port that the host is listening on.')
    parser.add_argument('-s', action='store', default='keys', dest='search',
                        help='OpenSSL argument to look for in certificate, use "keys" to get list of keys to retrieve.')
    parser.add_argument('-v', action='store_true', default=False, dest='verbose', help='Enable verbosity/debug.')
    parsed_arguments = parser.parse_args()
    self.host = parsed_arguments.host
    self.port = int(parsed_arguments.port)
    self.search = parsed_arguments.search
    self.verbose = parsed_arguments.verbose
    if self.host == None:
      print("host undefined use -h or --help")
      sys.exit(1)
    if self.verbose:
      print("Verbose mode enabled.")
      print("Logger set: DEBUG")
      logging.basicConfig(stream=sys.stdout, level=logging.INFO)
    else:
      logging.basicConfig(stream=sys.stdout, level=logging.WARN)

  @property
  def get_host(self):
    logging.info("get_host self.host = %s", self.host)
    return self.host

  @property
  def get_port(self):
    logging.info("get_port self.port =  %s", self.port)
    return self.port

  @property
  def get_search(self):
    logging.info("get_search self.search =  %s", self.search)
    return self.search

  @property
  def get_verbose(self):
    return self.verbose

# Create base SSL connection to address and port
class SSL(object):
  def __init__(self, host, port):
    self.host = host
    self.port = port
    self._ssl_sock = self._connector

  @property
  def _connector(self):
    address = (self.host, self.port)
    logging.info("_connector address = %s", address)
    ssl_context = ssl.create_default_context(ssl.Purpose.SERVER_AUTH)
    ssl_builder = ssl_context.wrap_socket(
      socket.socket(socket.AF_INET), server_hostname=self.host)
    ssl_builder.settimeout(3.0)
    try:
      ssl_builder.connect(address)
      logging.info("Created connection.")
    except:
      logging.error("Failed to create connection.")
      sys.exit(1)
    return ssl_builder

  @property
  def _set_peer_cert(self):
    ssl_connector = self._ssl_sock
    try:
      peer_cert = ssl_connector.getpeercert(binary_form=False)
      logging.info("_set_peer_cert peer_cert = %s", peer_cert)
    except:
      logging.error("_set_peer_cert failed to retrieve peer_cert %s", peer_cert)
      sys.exit(1)
    return peer_cert

  def get_peer_cert_values(self, requested_value):
    peer_cert = self._set_peer_cert
    pp = pprint.PrettyPrinter(indent=4)
    if requested_value == 'keys':
      print("Available keys to search for: ")
      for key, value in peer_cert.items():
        print(" * " + key + " ")
      return requested_value
    else:
      parsed_peer_cert = peer_cert[requested_value]
      return parsed_peer_cert


if __name__ == '__main__':
  cli = CLI()
  ssl = SSL(cli.get_host, cli.get_port)
  print(ssl.get_peer_cert_values(cli.get_search))