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diff --git a/definate/dns_generator.py b/definate/dns_generator.py
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+#!/usr/bin/python
+#
+# Copyright 2012 Google Inc. All Rights Reserved.
+#
+# 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.
+
+"""Generator for DNS based network definitions."""
+
+__author__ = 'msu@google.com (Martin Suess)'
+
+
+import logging
+import socket
+
+from third_party import ipaddr
+import generator
+
+
+class DnsGeneratorError(Exception):
+  """Exception to use when DnsGenerator fails."""
+
+
+class DnsGenerator(generator.Generator):
+  """Generator implementation for network definitions based on DNS."""
+
+  SUPPORTED_TYPES = ['A', 'AAAA']
+
+  def GenerateDefinition(self, config, unused_global_config):
+    """Generates a list of all nodes in a network definition.
+
+    This method basically processes all the configuration which is
+    hierarchically below "networks" in the "definitions" section in the
+    configuration file to generate a list of all nodes in that definition.
+
+    Args:
+      config: YAML configuration structure (dictionaries, lists and strings)
+        representing the "networks" section in "definitions" of the
+        configuration file.
+      unused_global_config: YAML configuration structure (dictionaries, lists
+        and strings) representing the "global" section of the configuration
+        file.
+
+    Returns:
+      Tuples of IPNetwork objects and string comments representing all the nodes
+      in one definition.
+
+    Raises:
+      DefinateConfigError: The configuration is not well formed.
+      DnsGeneratorError: There is a problem generating the output.
+    """
+    nodes = []
+    yaml_structure = {
+        'names': ['str'],
+        'types': ['str'],
+        }
+    for network in config:
+      self._yaml_validator.CheckConfiguration(network, yaml_structure)
+      for typ in network['types']:
+        if typ not in self.SUPPORTED_TYPES:
+          raise DnsGeneratorError('Unsupported DNS type found: %s' % typ)
+      for name in network['names']:
+        try:
+          addr_list = socket.getaddrinfo(name, None)
+        except socket.gaierror:
+          raise DnsGeneratorError('Hostname not found: %s' % name)
+        for family, _, _, _, sockaddr in addr_list:
+          ip_addr = None
+          if family == socket.AF_INET and 'A' in network['types']:
+            # sockaddr = (address, port)
+            ip_addr = ipaddr.IPv4Network(sockaddr[0])
+          elif family == socket.AF_INET6 and 'AAAA' in network['types']:
+            # sockaddr = (address, port, flow info, scope id)
+            ip_addr = ipaddr.IPv6Network(sockaddr[0])
+          else:
+            logging.debug('Skipping unknown AF \'%d\' for: %s', family, name)
+          if ip_addr:
+            nodes.append((ip_addr, name))
+    return nodes