ec2: Add IPv6 dhcp support to Ec2DataSource.

DataSourceEc2 now parses the metadata for each nic to determine if
configured for ipv6 and/or ipv4 addresses. In AWS for metadata version
2016-09-02, nics configured for ipv4 or ipv6 addresses will have non-zero
values stored in metadata at network/interfaces/macs/<MAC>/public-ipv4 or
ipv6s respectively. Those metadata files are only non-zero when an ipv4 or
ipv6 ip is associated to the specific nic. A new
DataSourceEc2.network_config property is added which parses the metadata
and renders a network version 1 dictionary representing both dhcp4 and
dhcp6 configuration for associated nics.

The network configuration returned from the datasource will also 'pin' the
nic name to the name presented on the instance for each nic.

LP: #1639030

1 files changed, 97 insertions, 0 deletions

diff --git a/tests/unittests/test_datasource/test_ec2.py b/tests/unittests/test_datasource/test_ec2.py
index 33d02619..e1ce6446 100644
--- a/tests/unittests/test_datasource/test_ec2.py
+++ b/tests/unittests/test_datasource/test_ec2.py
@@ -1,5 +1,6 @@
 # This file is part of cloud-init. See LICENSE file for license information.
 
+import copy
 import httpretty
 import mock
 
@@ -195,6 +196,34 @@ class TestEc2(test_helpers.HttprettyTestCase):
         return ds
 
     @httpretty.activate
+    def test_network_config_property_returns_version_1_network_data(self):
+        """network_config property returns network version 1 for metadata."""
+        ds = self._setup_ds(
+            platform_data=self.valid_platform_data,
+            sys_cfg={'datasource': {'Ec2': {'strict_id': True}}},
+            md=DEFAULT_METADATA)
+        ds.get_data()
+        mac1 = '06:17:04:d7:26:09'  # Defined in DEFAULT_METADATA
+        expected = {'version': 1, 'config': [
+            {'mac_address': '06:17:04:d7:26:09', 'name': 'eth9',
+             'subnets': [{'type': 'dhcp4'}, {'type': 'dhcp6'}],
+             'type': 'physical'}]}
+        patch_path = (
+            'cloudinit.sources.DataSourceEc2.net.get_interfaces_by_mac')
+        with mock.patch(patch_path) as m_get_interfaces_by_mac:
+            m_get_interfaces_by_mac.return_value = {mac1: 'eth9'}
+            self.assertEqual(expected, ds.network_config)
+
+    def test_network_config_property_is_cached_in_datasource(self):
+        """network_config property is cached in DataSourceEc2."""
+        ds = self._setup_ds(
+            platform_data=self.valid_platform_data,
+            sys_cfg={'datasource': {'Ec2': {'strict_id': True}}},
+            md=DEFAULT_METADATA)
+        ds._network_config = {'cached': 'data'}
+        self.assertEqual({'cached': 'data'}, ds.network_config)
+
+    @httpretty.activate
     @mock.patch('cloudinit.net.dhcp.maybe_perform_dhcp_discovery')
     def test_valid_platform_with_strict_true(self, m_dhcp):
         """Valid platform data should return true with strict_id true."""
@@ -287,4 +316,72 @@ class TestEc2(test_helpers.HttprettyTestCase):
         self.assertIn('Crawl of metadata service took', self.logs.getvalue())
 
 
+class TestConvertEc2MetadataNetworkConfig(test_helpers.CiTestCase):
+
+    def setUp(self):
+        super(TestConvertEc2MetadataNetworkConfig, self).setUp()
+        self.mac1 = '06:17:04:d7:26:09'
+        self.network_metadata = {
+            'network': {'interfaces': {'macs': {
+                self.mac1: {'public-ipv4s': '172.31.2.16'}}}}}
+
+    def test_convert_ec2_metadata_network_config_skips_absent_macs(self):
+        """Any mac absent from metadata is skipped by network config."""
+        macs_to_nics = {self.mac1: 'eth9', 'DE:AD:BE:EF:FF:FF': 'vitualnic2'}
+
+        # DE:AD:BE:EF:FF:FF represented by OS but not in metadata
+        expected = {'version': 1, 'config': [
+            {'mac_address': self.mac1, 'type': 'physical',
+             'name': 'eth9', 'subnets': [{'type': 'dhcp4'}]}]}
+        self.assertEqual(
+            expected,
+            ec2.convert_ec2_metadata_network_config(
+                self.network_metadata, macs_to_nics))
+
+    def test_convert_ec2_metadata_network_config_handles_only_dhcp6(self):
+        """Config dhcp6 when ipv6s is in metadata for a mac."""
+        macs_to_nics = {self.mac1: 'eth9'}
+        network_metadata_ipv6 = copy.deepcopy(self.network_metadata)
+        nic1_metadata = (
+            network_metadata_ipv6['network']['interfaces']['macs'][self.mac1])
+        nic1_metadata['ipv6s'] = '2620:0:1009:fd00:e442:c88d:c04d:dc85/64'
+        nic1_metadata.pop('public-ipv4s')
+        expected = {'version': 1, 'config': [
+            {'mac_address': self.mac1, 'type': 'physical',
+             'name': 'eth9', 'subnets': [{'type': 'dhcp6'}]}]}
+        self.assertEqual(
+            expected,
+            ec2.convert_ec2_metadata_network_config(
+                network_metadata_ipv6, macs_to_nics))
+
+    def test_convert_ec2_metadata_network_config_handles_dhcp4_and_dhcp6(self):
+        """Config both dhcp4 and dhcp6 when both vpc-ipv6 and ipv4 exists."""
+        macs_to_nics = {self.mac1: 'eth9'}
+        network_metadata_both = copy.deepcopy(self.network_metadata)
+        nic1_metadata = (
+            network_metadata_both['network']['interfaces']['macs'][self.mac1])
+        nic1_metadata['ipv6s'] = '2620:0:1009:fd00:e442:c88d:c04d:dc85/64'
+        expected = {'version': 1, 'config': [
+            {'mac_address': self.mac1, 'type': 'physical',
+             'name': 'eth9',
+             'subnets': [{'type': 'dhcp4'}, {'type': 'dhcp6'}]}]}
+        self.assertEqual(
+            expected,
+            ec2.convert_ec2_metadata_network_config(
+                network_metadata_both, macs_to_nics))
+
+    def test_convert_ec2_metadata_gets_macs_from_get_interfaces_by_mac(self):
+        """Convert Ec2 Metadata calls get_interfaces_by_mac by default."""
+        expected = {'version': 1, 'config': [
+            {'mac_address': self.mac1, 'type': 'physical',
+             'name': 'eth9',
+             'subnets': [{'type': 'dhcp4'}]}]}
+        patch_path = (
+            'cloudinit.sources.DataSourceEc2.net.get_interfaces_by_mac')
+        with mock.patch(patch_path) as m_get_interfaces_by_mac:
+            m_get_interfaces_by_mac.return_value = {self.mac1: 'eth9'}
+            self.assertEqual(
+                expected,
+                ec2.convert_ec2_metadata_network_config(self.network_metadata))
+
 # vi: ts=4 expandtab