cloud-init/SOURCES/0030-NM-renderer-set-default-IPv6-addr-gen-mode-for-all-i.patch

From c720ab9703752535767691a31e4720e11674bb1f Mon Sep 17 00:00:00 2001
From: Ani Sinha <anisinha@redhat.com>
Date: Fri, 4 Aug 2023 08:58:26 +0530
Subject: [PATCH] NM renderer: set default IPv6 addr-gen-mode for all
 interfaces to eui64 (#4291)

By default, NetworkManager renderer in cloud-init does not set any specific
method for IPV6 addr-gen-mode in the keyfiles it writes. Hence, implicitly the
mode is set to `eui64` in the absence of any global addr-gen-mode option in
NetworkManager configuration.
Later when other interfaces get added via D-Bus API or by using nmcli commands
without explictly setting an addr-gen-mode, NM auto generates new profiles for
those interfaces with addr-gen-mode set to `stable-privacy`. This introduces
inconsistency of configurations between interfaces based on how they were
added. This can cause problems for the customers.

In this change,  cloud-init overrides NetworkManager's preferred default of
`stable-privacy` to use EUI64 using a drop in NetworkManager configuration
file. This setting can be overriden by using global-connection-defaults
setting in /etc/NetworkManager/NetworkManager.conf file.

RHBZ: 2188388

Signed-off-by: Ani Sinha <anisinha@redhat.com>
(cherry picked from commit d41264cb4297a4b143a23f3677d33b81fbfc6e8e)

Conflicts:
	tests/unittests/test_net.py
---
 cloudinit/net/network_manager.py | 21 ++++++++
 tests/unittests/test_net.py      | 91 +++++++++++++++++++++++++-------
 2 files changed, 94 insertions(+), 18 deletions(-)

diff --git a/cloudinit/net/network_manager.py b/cloudinit/net/network_manager.py
index ca216928..8047f796 100644
--- a/cloudinit/net/network_manager.py
+++ b/cloudinit/net/network_manager.py
@@ -21,6 +21,15 @@ from cloudinit.net.network_state import NetworkState
 NM_RUN_DIR = "/etc/NetworkManager"
 NM_LIB_DIR = "/usr/lib/NetworkManager"
 NM_CFG_FILE = "/etc/NetworkManager/NetworkManager.conf"
+NM_IPV6_ADDR_GEN_CONF = """# This is generated by cloud-init. Do not edit.
+#
+[.config]
+  enable=nm-version-min:1.40
+[connection.30-cloud-init-ip6-addr-gen-mode]
+  # Select EUI64 to be used if the profile does not specify it.
+  ipv6.addr-gen-mode=0
+
+"""
 LOG = logging.getLogger(__name__)
 
 
@@ -368,6 +377,12 @@ class Renderer(renderer.Renderer):
             name = conn_filename(con_id, target)
             util.write_file(name, conn.dump(), 0o600)
 
+        # Select EUI64 to be used by default by NM for creating the address
+        # for use with RFC4862 IPv6 Stateless Address Autoconfiguration.
+        util.write_file(
+            cloud_init_nm_conf_filename(target), NM_IPV6_ADDR_GEN_CONF, 0o600
+        )
+
 
 def conn_filename(con_id, target=None):
     target_con_dir = subp.target_path(target, NM_RUN_DIR)
@@ -375,6 +390,12 @@ def conn_filename(con_id, target=None):
     return f"{target_con_dir}/system-connections/{con_file}"
 
 
+def cloud_init_nm_conf_filename(target=None):
+    target_con_dir = subp.target_path(target, NM_RUN_DIR)
+    conf_file = "30-cloud-init-ip6-addr-gen-mode.conf"
+    return f"{target_con_dir}/conf.d/{conf_file}"
+
+
 def available(target=None):
     # TODO: Move `uses_systemd` to a more appropriate location
     # It is imported here to avoid circular import
diff --git a/tests/unittests/test_net.py b/tests/unittests/test_net.py
index fd656a57..d49da696 100644
--- a/tests/unittests/test_net.py
+++ b/tests/unittests/test_net.py
@@ -5679,9 +5679,25 @@ class TestNetworkManagerRendering(CiTestCase):
     with_logs = True
 
     scripts_dir = "/etc/NetworkManager/system-connections"
+    conf_dir = "/etc/NetworkManager/conf.d"
 
     expected_name = "expected_network_manager"
 
+    expected_conf_d = {
+        "30-cloud-init-ip6-addr-gen-mode.conf": textwrap.dedent(
+            """\
+                # This is generated by cloud-init. Do not edit.
+                #
+                [.config]
+                  enable=nm-version-min:1.40
+                [connection.30-cloud-init-ip6-addr-gen-mode]
+                  # Select EUI64 to be used if the profile does not specify it.
+                  ipv6.addr-gen-mode=0
+
+                """
+        ),
+    }
+
     def _get_renderer(self):
         return network_manager.Renderer()
 
@@ -5700,11 +5716,19 @@ class TestNetworkManagerRendering(CiTestCase):
         renderer.render_network_state(ns, target=dir)
         return dir2dict(dir)
 
-    def _compare_files_to_expected(self, expected, found):
+    def _compare_files_to_expected(
+        self, expected_scripts, expected_conf, found
+    ):
         orig_maxdiff = self.maxDiff
-        expected_d = dict(
-            (os.path.join(self.scripts_dir, k), v) for k, v in expected.items()
+        conf_d = dict(
+            (os.path.join(self.conf_dir, k), v)
+            for k, v in expected_conf.items()
+        )
+        scripts_d = dict(
+            (os.path.join(self.scripts_dir, k), v)
+            for k, v in expected_scripts.items()
         )
+        expected_d = {**conf_d, **scripts_d}
 
         try:
             self.maxDiff = None
@@ -5765,6 +5789,7 @@ class TestNetworkManagerRendering(CiTestCase):
                 """
                 ),
             },
+            self.expected_conf_d,
             found,
         )
 
@@ -5820,8 +5845,9 @@ class TestNetworkManagerRendering(CiTestCase):
                 gateway=10.0.2.2
 
                 """
-                ),
+                )
             },
+            self.expected_conf_d,
             found,
         )
 
@@ -5857,33 +5883,44 @@ class TestNetworkManagerRendering(CiTestCase):
                 """
                 ),
             },
+            self.expected_conf_d,
             found,
         )
 
     def test_bond_config(self):
         entry = NETWORK_CONFIGS["bond"]
         found = self._render_and_read(network_config=yaml.load(entry["yaml"]))
-        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, found
+        )
 
     def test_vlan_config(self):
         entry = NETWORK_CONFIGS["vlan"]
         found = self._render_and_read(network_config=yaml.load(entry["yaml"]))
-        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, found
+        )
 
     def test_bridge_config(self):
         entry = NETWORK_CONFIGS["bridge"]
         found = self._render_and_read(network_config=yaml.load(entry["yaml"]))
-        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, found
+        )
 
     def test_manual_config(self):
         entry = NETWORK_CONFIGS["manual"]
         found = self._render_and_read(network_config=yaml.load(entry["yaml"]))
-        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, found
+        )
 
     def test_all_config(self):
         entry = NETWORK_CONFIGS["all"]
         found = self._render_and_read(network_config=yaml.load(entry["yaml"]))
-        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, found
+        )
         self.assertNotIn(
             "WARNING: Network config: ignoring eth0.101 device-level mtu",
             self.logs.getvalue(),
@@ -5892,12 +5929,16 @@ class TestNetworkManagerRendering(CiTestCase):
     def test_small_config(self):
         entry = NETWORK_CONFIGS["small"]
         found = self._render_and_read(network_config=yaml.load(entry["yaml"]))
-        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, found
+        )
 
     def test_v4_and_v6_static_config(self):
         entry = NETWORK_CONFIGS["v4_and_v6_static"]
         found = self._render_and_read(network_config=yaml.load(entry["yaml"]))
-        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, found
+        )
         expected_msg = (
             "WARNING: Network config: ignoring iface0 device-level mtu:8999"
             " because ipv4 subnet-level mtu:9000 provided."
@@ -5907,41 +5948,55 @@ class TestNetworkManagerRendering(CiTestCase):
     def test_dhcpv6_only_config(self):
         entry = NETWORK_CONFIGS["dhcpv6_only"]
         found = self._render_and_read(network_config=yaml.load(entry["yaml"]))
-        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, found
+        )
 
     def test_simple_render_ipv6_slaac(self):
         entry = NETWORK_CONFIGS["ipv6_slaac"]
         found = self._render_and_read(network_config=yaml.load(entry["yaml"]))
-        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, 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._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, found
+        )
 
     def test_wakeonlan_disabled_config_v2(self):
         entry = NETWORK_CONFIGS["wakeonlan_disabled"]
         found = self._render_and_read(
             network_config=yaml.load(entry["yaml_v2"])
         )
-        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, found
+        )
 
     def test_wakeonlan_enabled_config_v2(self):
         entry = NETWORK_CONFIGS["wakeonlan_enabled"]
         found = self._render_and_read(
             network_config=yaml.load(entry["yaml_v2"])
         )
-        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, found
+        )
 
     def test_render_v4_and_v6(self):
         entry = NETWORK_CONFIGS["v4_and_v6"]
         found = self._render_and_read(network_config=yaml.load(entry["yaml"]))
-        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, found
+        )
 
     def test_render_v6_and_v4(self):
         entry = NETWORK_CONFIGS["v6_and_v4"]
         found = self._render_and_read(network_config=yaml.load(entry["yaml"]))
-        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._compare_files_to_expected(
+            entry[self.expected_name], self.expected_conf_d, found
+        )
 
 
 @mock.patch(