designate/designate/mdns/handler.py

67 lines
2.1 KiB
Python

# Copyright 2014 Hewlett-Packard Development Company, L.P.
#
# Author: Kiall Mac Innes <kiall@hp.com>
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import dns
from oslo.config import cfg
from designate.openstack.common import log as logging
from designate import storage
LOG = logging.getLogger(__name__)
CONF = cfg.CONF
class RequestHandler(object):
def __init__(self):
# Get a storage connection
storage_driver = cfg.CONF['service:mdns'].storage_driver
self.storage = storage.get_storage(storage_driver)
def handle(self, payload):
request = dns.message.from_wire(payload)
# As we move further with the implementation, we'll want to:
# 1) Decode the payload using DNSPython
# 2) Hand off to either _handle_query or _handle_unsupported
# based on the OpCode
# 3) Gather the query results from storage
# 4) Build and return response using DNSPython.
if request.opcode() == dns.opcode.QUERY:
response = self._handle_query(request)
else:
response = self._handle_unsupported(request)
return response.to_wire()
def _handle_query(self, request):
"""Handle a DNS QUERY request"""
response = dns.message.make_response(request)
response.set_rcode(dns.rcode.SERVFAIL)
return response
def _handle_unsupported(self, request):
"""
Handle Unsupported DNS OpCode's
Unsupported OpCode's include STATUS, IQUERY, NOTIFY, UPDATE
"""
response = dns.message.make_response(request)
response.set_rcode(dns.rcode.REFUSED)
return response