From 69b6ab06ec5bf9a7eeb23b59ff7db821bde52be4 Mon Sep 17 00:00:00 2001
From: Tasos Sahanidis <tasos@tasossah.com>
Date: Sun, 16 Jun 2024 07:45:17 +0300
Subject: [PATCH] networkd: Implement ipv6-address-generation: stable-privacy

The relevant systemd pull request has long been merged, so add support
for IPv6Token=prefixstable in the networkd generator.

https://github.com/systemd/systemd/pull/16618
---
 doc/netplan-yaml.md            |  4 ++--
 src/networkd.c                 | 19 +++++++++++++------
 tests/generator/test_common.py | 15 ++++++++++++++-
 tests/generator/test_errors.py |  8 --------
 4 files changed, 29 insertions(+), 17 deletions(-)

diff --git a/doc/netplan-yaml.md b/doc/netplan-yaml.md
index fe3693748..b6b3280c4 100644
--- a/doc/netplan-yaml.md
+++ b/doc/netplan-yaml.md
@@ -451,8 +451,8 @@ Match devices by MAC when setting options like: `wakeonlan` or `*-offload`.
 - **`ipv6-address-generation`** (scalar) – since 0.99
 
   > Configure method for creating the address for use with RFC4862 IPv6
-  > Stateless Address Auto-configuration (only supported with `NetworkManager`
-  > back end). Possible values are `eui64` or `stable-privacy`.
+  > Stateless Address Auto-configuration.
+  > Possible values are `eui64` or `stable-privacy`.
 
 - **`ipv6-address-token`** (scalar) – since 0.100
 
diff --git a/src/networkd.c b/src/networkd.c
index babde5d07..70586c219 100644
--- a/src/networkd.c
+++ b/src/networkd.c
@@ -903,12 +903,19 @@ _netplan_netdef_write_network_file(
             g_string_append_printf(network, "Address=%s\n", g_array_index(def->ip6_addresses, char*, i));
     if (def->ip6_addr_gen_token) {
         g_string_append_printf(network, "IPv6Token=static:%s\n", def->ip6_addr_gen_token);
-    } else if (def->ip6_addr_gen_mode > NETPLAN_ADDRGEN_EUI64) {
-        /* EUI-64 mode is enabled by default, if no IPv6Token= is specified */
-        /* TODO: Enable stable-privacy mode for networkd, once PR#16618 has been released:
-         *       https://github.com/systemd/systemd/pull/16618 */
-        g_set_error(error, NETPLAN_BACKEND_ERROR, NETPLAN_ERROR_UNSUPPORTED, "ERROR: %s: ipv6-address-generation mode is not supported by networkd\n", def->id);
-        return FALSE;
+    } else {
+        switch (def->ip6_addr_gen_mode) {
+            case NETPLAN_ADDRGEN_DEFAULT:
+            case NETPLAN_ADDRGEN_EUI64:
+                break;
+            case NETPLAN_ADDRGEN_STABLEPRIVACY:
+                g_string_append(network, "IPv6Token=prefixstable\n");
+                break;
+            // LCOV_EXCL_START
+            default:
+                g_assert_not_reached();
+            // LCOV_EXCL_STOP
+        }
     }
     if (def->accept_ra == NETPLAN_RA_MODE_ENABLED)
         g_string_append_printf(network, "IPv6AcceptRA=yes\n");
diff --git a/tests/generator/test_common.py b/tests/generator/test_common.py
index d6552f3de..c4ea3c37f 100644
--- a/tests/generator/test_common.py
+++ b/tests/generator/test_common.py
@@ -765,10 +765,23 @@ def test_ip6_addr_gen_mode(self):
   version: 2
   renderer: networkd
   ethernets:
+    engreen:
+      dhcp6: yes
+      ipv6-address-generation: stable-privacy
     enblue:
       dhcp6: yes
       ipv6-address-generation: eui64''')
-        self.assert_networkd({'enblue.network': '''[Match]\nName=enblue\n
+        self.assert_networkd({'engreen.network': '''[Match]\nName=engreen\n
+[Network]
+DHCP=ipv6
+LinkLocalAddressing=ipv6
+IPv6Token=prefixstable
+
+[DHCP]
+RouteMetric=100
+UseMTU=true
+''',
+                              'enblue.network': '''[Match]\nName=enblue\n
 [Network]
 DHCP=ipv6
 LinkLocalAddressing=ipv6
diff --git a/tests/generator/test_errors.py b/tests/generator/test_errors.py
index f7a8d780d..d447c4920 100644
--- a/tests/generator/test_errors.py
+++ b/tests/generator/test_errors.py
@@ -350,14 +350,6 @@ def test_invalid_addr_gen_mode(self):
       ipv6-address-generation: 0''', expect_fail=True)
         self.assertIn("unknown ipv6-address-generation '0'", err)
 
-    def test_addr_gen_mode_not_supported(self):
-        err = self.generate('''network:
-  version: 2
-  ethernets:
-    engreen:
-      ipv6-address-generation: stable-privacy''', expect_fail=True)
-        self.assertIn("ERROR: engreen: ipv6-address-generation mode is not supported by networkd", err)
-
     def test_addr_gen_mode_and_addr_gen_token(self):
         err = self.generate('''network:
   version: 2