quay/util/ipresolver/__init__.py

import logging
import json
import time

from collections import namedtuple, defaultdict

from threading import Thread, Lock
from abc import ABCMeta, abstractmethod
from six import add_metaclass
from cachetools import ttl_cache, lru_cache
from netaddr import IPNetwork, IPAddress, IPSet, AddrFormatError

import geoip2.database
import geoip2.errors
import requests

from util.abchelpers import nooper

ResolvedLocation = namedtuple('ResolvedLocation', ['provider', 'region', 'service', 'sync_token'])

logger = logging.getLogger(__name__)

_DATA_FILES = {'aws-ip-ranges.json': 'https://ip-ranges.amazonaws.com/ip-ranges.json'}
_UPDATE_INTERVAL = 600
_FAILED_UPDATE_RETRY_SECS = 60

CACHE = {}
CACHE_LOCK = Lock()

def update_resolver_datafiles():
  """ Performs an update of the data file(s) used by the IP Resolver. """
  for filename, url in _DATA_FILES.iteritems():
    logger.debug('Updating IP resolver data file "%s" from URL "%s"', filename, url)
    with open('util/ipresolver/%s' % filename, 'w') as f:
      response = requests.get(url)
      logger.debug('Got %s response for URL %s', response.status_code, url)
      if response.status_code / 2 != 100:
        raise Exception('Got non-2XX status code for URL %s: %s' % (url, response.status_code))

      f.write(response.text)
      logger.debug('Successfully wrote %s', filename)

def _get_aws_ip_ranges():
  try:
    with open('util/ipresolver/aws-ip-ranges.json', 'r') as f:
      return json.loads(f.read())
  except IOError:
    logger.exception('Could not load AWS IP Ranges')
    return None
  except ValueError:
    logger.exception('Could not load AWS IP Ranges')
    return None
  except TypeError:
    logger.exception('Could not load AWS IP Ranges')
    return None


@add_metaclass(ABCMeta)
class IPResolverInterface(object):
  """ Helper class for resolving information about an IP address. """
  @abstractmethod
  def resolve_ip(self, ip_address):
    """ Attempts to return resolved information about the specified IP Address. If such an attempt
        fails, returns None.
    """
    pass

  @abstractmethod
  def is_ip_possible_threat(self, ip_address):
    """ Attempts to return whether the given IP address is a possible abuser or spammer.
        Returns False if the IP address information could not be looked up.
    """
    pass


@nooper
class NoopIPResolver(IPResolverInterface):
  """ No-op version of the security scanner API. """
  pass


class IPResolver(IPResolverInterface):
  def __init__(self, app):
    self.app = app
    self.geoip_db = geoip2.database.Reader('util/ipresolver/GeoLite2-Country.mmdb')
    self._worker = _UpdateIPRange(_UPDATE_INTERVAL)
    self._worker_started = False

  @ttl_cache(maxsize=100, ttl=600)
  def is_ip_possible_threat(self, ip_address):
    if self.app.config.get('THREAT_NAMESPACE_MAXIMUM_BUILD_COUNT') is None:
      return False

    if self.app.config.get('IP_DATA_API_KEY') is None:
      return False

    if not ip_address:
      return False

    api_key = self.app.config['IP_DATA_API_KEY']

    try:
      logger.debug('Requesting IP data for IP %s', ip_address)
      r = requests.get('https://api.ipdata.co/%s/threat?api-key=%s' % (ip_address, api_key),
                       timeout=1)
      if r.status_code != 200:
        logger.debug('Got non-200 response for IP %s: %s', ip_address, r.status_code)
        return False

      logger.debug('Got IP data for IP %s: %s => %s', ip_address, r.status_code, r.json())
      threat_data = r.json()
      return threat_data.get('is_threat', False) or threat_data.get('is_bogon', False)
    except requests.RequestException:
      logger.exception('Got exception when trying to lookup IP Address')
    except ValueError:
      logger.exception('Got exception when trying to lookup IP Address')
    except Exception:
      logger.exception('Got exception when trying to lookup IP Address')

    return False

  def resolve_ip(self, ip_address):
    """ Attempts to return resolved information about the specified IP Address. If such an attempt
        fails, returns None.
    """
    location_function = self._get_location_function()
    if not ip_address or not location_function:
      return None

    return location_function(ip_address)

  def _get_location_function(self):
    if (not self.app.config.get('TESTING', False) and not self._worker_started and
        not self._worker.is_alive()):
      try:
        self._worker.start()
        self._worker_started = True
      except:
        logger.exception('Got exception try to start ip resolver thread')

    try:
      cache = CACHE
      sync_token = cache.get('sync_token', None)
      if sync_token is None:
        logger.debug('The aws ip range has not been cached from %s', _DATA_FILES['aws-ip-ranges.json'])
        return None

      all_amazon = cache['all_amazon']
      regions = cache['regions']
    except KeyError:
      logger.exception('Got exception trying to hit aws ip range cache')
      return None
    except Exception:
      logger.exception('Got exception trying to hit aws ip range cache')
      return None

    return IPResolver._build_location_function(sync_token, all_amazon, regions, self.geoip_db)

  @staticmethod
  def _build_location_function(sync_token, all_amazon, regions, country_db):
    @lru_cache(maxsize=4096)
    def _get_location(ip_address):
      try:
        parsed_ip = IPAddress(ip_address)
      except AddrFormatError:
        return ResolvedLocation('invalid_ip', None, None, sync_token)

      if parsed_ip not in all_amazon:
        # Try geoip classification
        try:
          found = country_db.country(parsed_ip)
          return ResolvedLocation(
            'internet',
            found.continent.code,
            found.country.iso_code,
            sync_token,
          )
        except geoip2.errors.AddressNotFoundError:
          return ResolvedLocation('internet', None, None, sync_token)

      region = None

      for region_name, region_set in regions.items():
        if parsed_ip in region_set:
          region = region_name
          break

      return ResolvedLocation('aws', region, None, sync_token)
    return _get_location

  @staticmethod
  def _parse_amazon_ranges(ranges):
    all_amazon = IPSet()
    regions = defaultdict(IPSet)

    for service_description in ranges['prefixes']:
      cidr = IPNetwork(service_description['ip_prefix'])
      region = service_description['region']

      all_amazon.add(cidr)
      regions[region].add(cidr)

    return all_amazon, regions


class _UpdateIPRange(Thread):
  """Helper class that uses a thread to loads the IP ranges from Amazon"""
  def  __init__(self, interval):
    Thread.__init__(self)
    self.interval = interval

  def run(self):
    while True:
      logger.debug('Updating aws ip range from "%s"', 'util/ipresolver/aws-ip-ranges.json')
      aws_ip_range_json = _get_aws_ip_ranges()
      if aws_ip_range_json is None:
        logger.exception('Failed trying to update aws ip range')
        time.sleep(_FAILED_UPDATE_RETRY_SECS)
        continue

      sync_token = aws_ip_range_json['syncToken']
      all_amazon, regions = IPResolver._parse_amazon_ranges(aws_ip_range_json)

      with CACHE_LOCK:
        CACHE['sync_token'] = sync_token
        CACHE['all_amazon'] = all_amazon
        CACHE['regions'] = regions

      time.sleep(self.interval)