libnm: add "dns-data" replacement for "ipv[46].dns" properties on D-Bus

On D-Bus, the properties "ipv[46].dns" are of type "au" and "aay",
respectively.

Btw, in particular "au" is bad, because we put there a big-endian
number. There is no D-Bus type to represent big endian numbers, so "u"
is bad because it can cause endianess problem when trying to remote
the D-Bus communication to another host (without explicitly
understanding which "u" properties need to swap for endinness).

Anyway. The plain addresses are not enough. We soon will also support
the DNS-over-TLS server name, or maybe a DoT port number. The previous
property was not extensible, so deprecate it and replace it by
"dns-data".

This one is just a list of strings. That is unlike "address-data" or
"route-data", which do a similar thing but are "a{sv}" dictionaries.
Here a string is supposed to be sufficient also for the future. Also,
because in nmcli and keyfile will will simply have a string format for
representing the extra data, not a structure (unlike for routes or
addresses).

src/libnm-core-impl/nm-setting-ip-config.c

@@ -5829,6 +5829,35 @@ _nm_setting_property_from_dbus_fcn_direct_ip_config_gateway(
                                                      error);
 }
 
+static GVariant *
+dns_data_to_dbus(_NM_SETT_INFO_PROP_TO_DBUS_FCN_ARGS _nm_nil)
+{
+    GPtrArray *arr;
+
+    if (!_nm_connection_serialize_non_secret(flags))
+        return NULL;
+
+    arr = _nm_setting_ip_config_get_dns_array(NM_SETTING_IP_CONFIG(setting));
+    if (nm_g_ptr_array_len(arr) == 0)
+        return NULL;
+    return g_variant_new_strv((const char *const *) arr->pdata, arr->len);
+}
+
+static gboolean
+dns_data_from_dbus(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
+{
+    gs_free const char **strv = NULL;
+
+    if (_nm_setting_use_legacy_property(setting, connection_dict, "dns", "dns-data")) {
+        *out_is_modified = FALSE;
+        return TRUE;
+    }
+
+    strv = g_variant_get_strv(value, NULL);
+    g_object_set(setting, NM_SETTING_IP_CONFIG_DNS, strv, NULL);
+    return TRUE;
+}
+
 GArray *
 _nm_sett_info_property_override_create_array_ip_config(int addr_family)
 {
@@ -5915,6 +5944,21 @@ _nm_sett_info_property_override_create_array_ip_config(int addr_family)
         .direct_offset =
             NM_STRUCT_OFFSET_ENSURE_TYPE(bool, NMSettingIPConfigPrivate, ignore_auto_dns));
 
+    /* ---dbus---
+     * property: dns-data
+     * format: array of strings
+     * description: Array of DNS name servers. This replaces the deprecated
+     *   "dns" property. Each name server can also contain a DoT server name.
+     * ---end---
+     */
+    _nm_properties_override_dbus(
+        properties_override,
+        "dns-data",
+        NM_SETT_INFO_PROPERT_TYPE_DBUS(NM_G_VARIANT_TYPE("as"),
+                                       .to_dbus_fcn   = dns_data_to_dbus,
+                                       .compare_fcn   = _nm_setting_property_compare_fcn_ignore,
+                                       .from_dbus_fcn = dns_data_from_dbus, ));
+
     _nm_properties_override_gobj(
         properties_override,
         obj_properties[PROP_DNS_PRIORITY],
@@ -6156,11 +6200,13 @@ nm_setting_ip_config_class_init(NMSettingIPConfigClass *klass)
      *
      * Array of IP addresses of DNS servers.
      **/
-    obj_properties[PROP_DNS] = g_param_spec_boxed(NM_SETTING_IP_CONFIG_DNS,
+    obj_properties[PROP_DNS] =
-                                                  "",
+        g_param_spec_boxed(NM_SETTING_IP_CONFIG_DNS,
-                                                  "",
+                           "",
-                                                  G_TYPE_STRV,
+                           "",
-                                                  G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
+                           G_TYPE_STRV,
+                           /* On D-Bus, "dns" is deprecated for "dns-data". */
+                           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
 
     /**
      * NMSettingIPConfig:dns-search:

src/libnm-core-impl/nm-setting-ip4-config.c

@@ -395,10 +395,19 @@ ip4_dns_to_dbus(_NM_SETT_INFO_PROP_TO_DBUS_FCN_ARGS _nm_nil)
     return _nm_utils_ip4_dns_to_variant((const char *const *) dns->pdata, dns->len);
 }
 
-static void
+static gboolean
-ip4_dns_from_dbus(_NM_SETT_INFO_PROP_FROM_DBUS_GPROP_FCN_ARGS _nm_nil)
+ip4_dns_from_dbus(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
 {
-    g_value_take_boxed(to, nm_utils_ip4_dns_from_variant(from));
+    gs_strfreev char **strv = NULL;
+
+    if (!_nm_setting_use_legacy_property(setting, connection_dict, "dns", "dns-data")) {
+        *out_is_modified = FALSE;
+        return TRUE;
+    }
+
+    strv = nm_utils_ip4_dns_from_variant(value);
+    g_object_set(setting, NM_SETTING_IP_CONFIG_DNS, strv, NULL);
+    return TRUE;
 }
 
 static GVariant *
@@ -964,11 +973,11 @@ nm_setting_ip4_config_class_init(NMSettingIP4ConfigClass *klass)
         properties_override,
         g_object_class_find_property(G_OBJECT_CLASS(setting_class), NM_SETTING_IP_CONFIG_DNS),
         NM_SETT_INFO_PROPERT_TYPE_DBUS(NM_G_VARIANT_TYPE("au"),
-                                       .compare_fcn = _nm_setting_property_compare_fcn_default,
+                                       .compare_fcn   = _nm_setting_property_compare_fcn_default,
-                                       .to_dbus_fcn = ip4_dns_to_dbus,
+                                       .to_dbus_fcn   = ip4_dns_to_dbus,
-                                       .typdata_from_dbus.gprop_fcn = ip4_dns_from_dbus,
+                                       .from_dbus_fcn = ip4_dns_from_dbus, ),
-                                       .from_dbus_fcn = _nm_setting_property_from_dbus_fcn_gprop,
+        .to_dbus_only_in_manager_process = TRUE,
-                                       .from_dbus_is_full = TRUE), );
+        .dbus_deprecated                 = TRUE, );
 
     /* ---dbus---
      * property: addresses

src/libnm-core-impl/nm-setting-ip6-config.c

@@ -396,10 +396,19 @@ ip6_dns_to_dbus(_NM_SETT_INFO_PROP_TO_DBUS_FCN_ARGS _nm_nil)
     return _nm_utils_ip6_dns_to_variant((const char *const *) dns->pdata, dns->len);
 }
 
-static void
+static gboolean
-ip6_dns_from_dbus(_NM_SETT_INFO_PROP_FROM_DBUS_GPROP_FCN_ARGS _nm_nil)
+ip6_dns_from_dbus(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
 {
-    g_value_take_boxed(to, nm_utils_ip6_dns_from_variant(from));
+    gs_strfreev char **strv = NULL;
+
+    if (!_nm_setting_use_legacy_property(setting, connection_dict, "dns", "dns-data")) {
+        *out_is_modified = FALSE;
+        return TRUE;
+    }
+
+    strv = nm_utils_ip6_dns_from_variant(value);
+    g_object_set(setting, NM_SETTING_IP_CONFIG_DNS, strv, NULL);
+    return TRUE;
 }
 
 static GVariant *
@@ -973,11 +982,11 @@ nm_setting_ip6_config_class_init(NMSettingIP6ConfigClass *klass)
         properties_override,
         g_object_class_find_property(G_OBJECT_CLASS(setting_class), NM_SETTING_IP_CONFIG_DNS),
         NM_SETT_INFO_PROPERT_TYPE_DBUS(NM_G_VARIANT_TYPE("aay"),
-                                       .compare_fcn = _nm_setting_property_compare_fcn_default,
+                                       .compare_fcn   = _nm_setting_property_compare_fcn_default,
-                                       .to_dbus_fcn = ip6_dns_to_dbus,
+                                       .to_dbus_fcn   = ip6_dns_to_dbus,
-                                       .typdata_from_dbus.gprop_fcn = ip6_dns_from_dbus,
+                                       .from_dbus_fcn = ip6_dns_from_dbus, ),
-                                       .from_dbus_fcn = _nm_setting_property_from_dbus_fcn_gprop,
+        .to_dbus_only_in_manager_process = TRUE,
-                                       .from_dbus_is_full = TRUE));
+        .dbus_deprecated                 = TRUE);
 
     /* ---dbus---
      * property: addresses