net: handle openstack dhcpv6-stateless configuration

Openstack subnets can be configured to use SLAAC by setting
ipv6_address_mode=dhcpv6-stateless. When this is the case
the sysconfig interface configuration should use
IPV6_AUTOCONF=yes and not set DHCPV6C=yes.

This change sets the subnets type property to the full
network['type'] from openstack metadata.

cloudinit/net/sysconfig.py and cloudinit/net/eni.py
are updated to support new subnet types:
  - 'ipv6_dhcpv6-stateless' => IPV6_AUTOCONF=yes
  - 'ipv6_dhcpv6-stateful' => DHCPV6C=yes

Type 'dhcp6' in sysconfig is kept for backward compatibility
with any implementations that set subnet_type == 'dhcp6'.

LP: #1847517

1 files changed, 88 insertions, 0 deletions

diff --git a/tests/unittests/test_net.py b/tests/unittests/test_net.py
index b6597412..f5a9cae6 100644
--- a/tests/unittests/test_net.py
+++ b/tests/unittests/test_net.py
@@ -1070,6 +1070,82 @@ NETWORK_CONFIGS = {
                 """),
         },
     },
+    'dhcpv6_stateless': {
+        'expected_eni': textwrap.dedent("""\
+        auto lo
+        iface lo inet loopback
+
+        auto iface0
+        iface iface0 inet6 auto
+    """).rstrip(' '),
+        'expected_netplan': textwrap.dedent("""
+        network:
+            version: 2
+            ethernets:
+                iface0:
+                    dhcp6: true
+    """).rstrip(' '),
+        'yaml': textwrap.dedent("""\
+        version: 1
+        config:
+          - type: 'physical'
+            name: 'iface0'
+            subnets:
+            - {'type': 'ipv6_dhcpv6-stateless'}
+    """).rstrip(' '),
+        'expected_sysconfig': {
+            'ifcfg-iface0': textwrap.dedent("""\
+            BOOTPROTO=none
+            DEVICE=iface0
+            IPV6_AUTOCONF=yes
+            IPV6INIT=yes
+            DEVICE=iface0
+            NM_CONTROLLED=no
+            ONBOOT=yes
+            STARTMODE=auto
+            TYPE=Ethernet
+            USERCTL=no
+            """),
+        },
+    },
+    'dhcpv6_stateful': {
+        'expected_eni': textwrap.dedent("""\
+        auto lo
+        iface lo inet loopback
+
+        auto iface0
+        iface iface0 inet6 dhcp
+    """).rstrip(' '),
+        'expected_netplan': textwrap.dedent("""
+        network:
+            version: 2
+            ethernets:
+                iface0:
+                    dhcp6: true
+    """).rstrip(' '),
+        'yaml': textwrap.dedent("""\
+        version: 1
+        config:
+          - type: 'physical'
+            name: 'iface0'
+            subnets:
+            - {'type': 'ipv6_dhcpv6-stateful'}
+    """).rstrip(' '),
+        'expected_sysconfig': {
+            'ifcfg-iface0': textwrap.dedent("""\
+            BOOTPROTO=none
+            DEVICE=iface0
+            DHCPV6C=yes
+            IPV6INIT=yes
+            DEVICE=iface0
+            NM_CONTROLLED=no
+            ONBOOT=yes
+            STARTMODE=auto
+            TYPE=Ethernet
+            USERCTL=no
+            """),
+        },
+    },
     'all': {
         'expected_eni': ("""\
 auto lo
@@ -2781,6 +2857,18 @@ USERCTL=no
         self._compare_files_to_expected(entry[self.expected_name], found)
         self._assert_headers(found)
 
+    def test_dhcpv6_stateless_config(self):
+        entry = NETWORK_CONFIGS['dhcpv6_stateless']
+        found = self._render_and_read(network_config=yaml.load(entry['yaml']))
+        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._assert_headers(found)
+
+    def test_dhcpv6_stateful_config(self):
+        entry = NETWORK_CONFIGS['dhcpv6_stateful']
+        found = self._render_and_read(network_config=yaml.load(entry['yaml']))
+        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._assert_headers(found)
+
     def test_check_ifcfg_rh(self):
         """ifcfg-rh plugin is added NetworkManager.conf if conf present."""
         render_dir = self.tmp_dir()