old_contents: #!/usr/bin/env python
  
  # This Source Code Form is subject to the terms of the Mozilla Public
  # License, v. 2.0. If a copy of the MPL was not distributed with this
  # file, You can obtain one at http://mozilla.org/MPL/2.0/.
  # Copyright (c) 2014 Mozilla Corporation
  
  
  from lib.alerttask import AlertTask
  from query_models import QueryStringMatch, SearchQuery, TermMatch
  
  
  class AlertProxyDropNonStandardPort(AlertTask):
      def main(self):
          search_query = SearchQuery(minutes=20)
  
          search_query.add_must([
              TermMatch('category', 'squid'),
              TermMatch('tags', 'squid'),
              TermMatch('details.proxyaction', 'TCP_DENIED/-'),
              TermMatch('details.tcpaction', 'CONNECT')
          ])
  
          search_query.add_must_not([
              QueryStringMatch('details.destination: /.*:443/')
          ])
  
          self.filtersManual(search_query)
  
          # Search aggregations on field 'hostname', keep X samples of
          # events at most
          self.searchEventsAggregated('details.sourceipaddress', samplesLimit=10)
          # alert when >= X matching events in an aggregation
          # I think it makes sense to alert every time here
          self.walkAggregations(threshold=1)
  
          # Set alert properties
      def onAggregation(self, aggreg):
           # aggreg['count']: number of items in the aggregation, ex: number of failed login attempts
           # aggreg['value']: value of the aggregation field, ex: toto@example.com
           # aggreg['events']: list of events in the aggregation
          category = 'squid'
          tags = ['squid', 'proxy']
          severity = 'WARNING'
  
          destinations = set()
          for event in aggreg['allevents']:
              destinations.add(event['_source']['details']['destination'])
  
          summary = 'Suspicious Proxy DROP events detected from {0} to the following non-std port(s): {1}'.format(
              aggreg['value'],
              ",".join(sorted(destinations))
          )
  
          # Create the alert object based on these properties
          return self.createAlertDict(summary, category, tags, aggreg['events'], severity)
  
new_contents: #!/usr/bin/env python
  
  # This Source Code Form is subject to the terms of the Mozilla Public
  # License, v. 2.0. If a copy of the MPL was not distributed with this
  # file, You can obtain one at http://mozilla.org/MPL/2.0/.
  # Copyright (c) 2014 Mozilla Corporation
  
  
  from lib.alerttask import AlertTask
  from query_models import QueryStringMatch, SearchQuery, TermMatch
  
  
  class AlertProxyDropNonStandardPort(AlertTask):
      def main(self):
          self.parse_config(
              'proxy_drop_non_standard_port.conf', ['excludedports'])
  
          search_query = SearchQuery(minutes=20)
  
          search_query.add_must([
              TermMatch('category', 'squid'),
              TermMatch('tags', 'squid'),
              TermMatch('details.proxyaction', 'TCP_DENIED/-'),
              TermMatch('details.tcpaction', 'CONNECT')
          ])
  
          # Only notify on certain file extensions from config
          filename_regex = "/.*:({0})/".format(
              self.config.excludedports.replace(',', '|'))
          search_query.add_must_not([
              QueryStringMatch('details.destination: {}'.format(filename_regex))
          ])
  
          self.filtersManual(search_query)
  
          # Search aggregations on field 'hostname', keep X samples of
          # events at most
          self.searchEventsAggregated('details.sourceipaddress', samplesLimit=10)
          # alert when >= X matching events in an aggregation
          # I think it makes sense to alert every time here
          self.walkAggregations(threshold=1)
  
          # Set alert properties
      def onAggregation(self, aggreg):
           # aggreg['count']: number of items in the aggregation, ex: number of failed login attempts
           # aggreg['value']: value of the aggregation field, ex: toto@example.com
           # aggreg['events']: list of events in the aggregation
          category = 'squid'
          tags = ['squid', 'proxy']
          severity = 'WARNING'
  
          destinations = set()
          for event in aggreg['allevents']:
              destinations.add(event['_source']['details']['destination'])
  
          summary = 'Suspicious Proxy DROP events detected from {0} to the following non-std port(s): {1}'.format(
              aggreg['value'],
              ",".join(sorted(destinations))
          )
  
          # Create the alert object based on these properties
          return self.createAlertDict(summary, category, tags, aggreg['events'], severity)
  
subject: Make excluded ports configurable