core: persist state of software generic devices across restarts

When a generic connection has a custom device-handler, it always
generates a NMDeviceGeneric, even when the link that gets created is
of a type natively supported by NM. On service restart, we need to
keep track that the device is generic or otherwise a different device
type will be instantiated.

(cherry picked from commit f2613be150)

src/core/devices/nm-device-factory.c

@@ -28,6 +28,10 @@ G_DEFINE_ABSTRACT_TYPE(NMDeviceFactory, nm_device_factory, G_TYPE_OBJECT)
 
 /*****************************************************************************/
 
+static NMDeviceFactory *generic_factory;
+
+/*****************************************************************************/
+
 static void
 nm_device_factory_get_supported_types(NMDeviceFactory    *factory,
                                       const NMLinkType  **out_link_types,
@@ -66,7 +70,8 @@ nm_device_factory_create_device(NMDeviceFactory      *factory,
     if (plink) {
         g_return_val_if_fail(!connection, NULL);
         g_return_val_if_fail(strcmp(iface, plink->name) == 0, NULL);
-        nm_assert(factory == nm_device_factory_manager_find_factory_for_link_type(plink->type));
+        nm_assert(factory == nm_device_factory_manager_find_factory_for_link_type(plink->type)
+                  || factory == generic_factory);
     } else if (connection)
         nm_assert(factory == nm_device_factory_manager_find_factory_for_connection(connection));
     else
@@ -184,6 +189,12 @@ static void __attribute__((destructor)) _cleanup(void)
     nm_clear_pointer(&factories_by_setting, g_hash_table_unref);
 }
 
+NMDeviceFactory *
+nm_device_factory_get_generic_factory(void)
+{
+    return generic_factory;
+}
+
 NMDeviceFactory *
 nm_device_factory_manager_find_factory_for_link_type(NMLinkType link_type)
 {
@@ -300,9 +311,12 @@ _load_internal_factory(GType                             factory_gtype,
                        gpointer                          user_data)
 {
     gs_unref_object NMDeviceFactory *factory = NULL;
+    GType                            nm_generic_device_factory_get_type(void);
 
     factory = g_object_new(factory_gtype, NULL);
     _add_factory(factory, NULL, callback, user_data);
+    if (factory_gtype == nm_generic_device_factory_get_type())
+        generic_factory = factory;
 }
 
 static void

src/core/devices/nm-device-factory.h

@@ -234,4 +234,6 @@ NMDeviceFactory *nm_device_factory_manager_find_factory_for_connection(NMConnect
 void nm_device_factory_manager_for_each_factory(NMDeviceFactoryManagerFactoryFunc callback,
                                                 gpointer                          user_data);
 
+NMDeviceFactory *nm_device_factory_get_generic_factory(void);
+
 #endif /* __NETWORKMANAGER_DEVICE_FACTORY_H__ */

src/core/nm-config.c

@@ -2354,9 +2354,10 @@ _nm_config_state_set(NMConfig *self, gboolean allow_persist, gboolean force_pers
     "route-metric-default-aspired"
 #define DEVICE_RUN_STATE_KEYFILE_KEY_DEVICE_ROUTE_METRIC_DEFAULT_EFFECTIVE \
     "route-metric-default-effective"
-#define DEVICE_RUN_STATE_KEYFILE_KEY_DEVICE_ROOT_PATH     "root-path"
+#define DEVICE_RUN_STATE_KEYFILE_KEY_DEVICE_ROOT_PATH        "root-path"
-#define DEVICE_RUN_STATE_KEYFILE_KEY_DEVICE_NEXT_SERVER   "next-server"
+#define DEVICE_RUN_STATE_KEYFILE_KEY_DEVICE_NEXT_SERVER      "next-server"
-#define DEVICE_RUN_STATE_KEYFILE_KEY_DEVICE_DHCP_BOOTFILE "dhcp-bootfile"
+#define DEVICE_RUN_STATE_KEYFILE_KEY_DEVICE_DHCP_BOOTFILE    "dhcp-bootfile"
+#define DEVICE_RUN_STATE_KEYFILE_KEY_DEVICE_GENERIC_SOFTWARE "generic-software"
 
 static NM_UTILS_LOOKUP_STR_DEFINE(
     _device_state_managed_type_to_str,
@@ -2457,6 +2458,12 @@ _config_device_state_data_new(int ifindex, GKeyFile *kf)
     device_state->route_metric_default_aspired   = route_metric_default_aspired;
     device_state->route_metric_default_effective = route_metric_default_effective;
 
+    device_state->generic_sw =
+        nm_config_keyfile_get_boolean(kf,
+                                      DEVICE_RUN_STATE_KEYFILE_GROUP_DEVICE,
+                                      DEVICE_RUN_STATE_KEYFILE_KEY_DEVICE_GENERIC_SOFTWARE,
+                                      FALSE);
+
     p = (char *) (&device_state[1]);
     if (connection_uuid) {
         memcpy(p, connection_uuid, connection_uuid_len);
@@ -2502,7 +2509,7 @@ nm_config_device_state_load(int ifindex)
                        ? ", nm-owned=1"
                        : (device_state->nm_owned == NM_TERNARY_FALSE ? ", nm-owned=0" : "");
 
-    _LOGT("device-state: %s #%d (%s); managed=%s%s%s%s%s%s%s%s, "
+    _LOGT("device-state: %s #%d (%s); managed=%s%s%s%s%s%s%s%s%s, "
           "route-metric-default=%" G_GUINT32_FORMAT "-%" G_GUINT32_FORMAT "",
           kf ? "read" : "miss",
           ifindex,
@@ -2519,6 +2526,7 @@ nm_config_device_state_load(int ifindex)
                               "",
                               ""),
           nm_owned_str,
+          device_state->generic_sw ? ", generic-software" : "",
           device_state->route_metric_default_aspired,
           device_state->route_metric_default_effective);
 
@@ -2577,7 +2585,8 @@ nm_config_device_state_write(int                            ifindex,
                              guint32                        route_metric_default_aspired,
                              guint32                        route_metric_default_effective,
                              NMDhcpConfig                  *dhcp4_config,
-                             NMDhcpConfig                  *dhcp6_config)
+                             NMDhcpConfig                  *dhcp6_config,
+                             gboolean                       generic_sw)
 {
     char    path[NM_STRLEN(NM_CONFIG_DEVICE_STATE_DIR "/") + DEVICE_STATE_FILENAME_LEN_MAX + 1];
     GError *local                                 = NULL;
@@ -2664,6 +2673,13 @@ nm_config_device_state_write(int                            ifindex,
                               dhcp_bootfile);
     }
 
+    if (generic_sw) {
+        g_key_file_set_boolean(kf,
+                               DEVICE_RUN_STATE_KEYFILE_GROUP_DEVICE,
+                               DEVICE_RUN_STATE_KEYFILE_KEY_DEVICE_GENERIC_SOFTWARE,
+                               TRUE);
+    }
+
     for (IS_IPv4 = 1; IS_IPv4 >= 0; IS_IPv4--) {
         NMDhcpConfig              *dhcp_config = IS_IPv4 ? dhcp4_config : dhcp6_config;
         gs_free NMUtilsNamedValue *values      = NULL;
@@ -2691,7 +2707,7 @@ nm_config_device_state_write(int                            ifindex,
         g_error_free(local);
         return FALSE;
     }
-    _LOGT("device-state: write #%d (%s); managed=%s%s%s%s%s%s%s, "
+    _LOGT("device-state: write #%d (%s); managed=%s%s%s%s%s%s%s%s, "
           "route-metric-default=%" G_GUINT32_FORMAT "-%" G_GUINT32_FORMAT "%s%s%s"
           "%s%s%s"
           "%s%s%s",
@@ -2700,6 +2716,7 @@ nm_config_device_state_write(int                            ifindex,
           _device_state_managed_type_to_str(managed),
           NM_PRINT_FMT_QUOTED(connection_uuid, ", connection-uuid=", connection_uuid, "", ""),
           NM_PRINT_FMT_QUOTED(perm_hw_addr_fake, ", perm-hw-addr-fake=", perm_hw_addr_fake, "", ""),
+          generic_sw ? ", generic-software" : "",
           route_metric_default_aspired,
           route_metric_default_effective,
           NM_PRINT_FMT_QUOTED(next_server, ", next-server=", next_server, "", ""),

src/core/nm-config.h

@@ -176,6 +176,8 @@ struct _NMConfigDeviceStateData {
     /* whether the device was nm-owned (0/1) or -1 for
      * non-software devices. */
     NMTernary nm_owned : 3;
+    /* whether the device is a generic one created by NM */
+    bool generic_sw : 1;
 };
 
 NMConfigDeviceStateData *nm_config_device_state_load(int ifindex);
@@ -188,7 +190,8 @@ gboolean                 nm_config_device_state_write(int
                                                       guint32                        route_metric_default_aspired,
                                                       guint32                        route_metric_default_effective,
                                                       NMDhcpConfig                  *dhcp4_config,
-                                                      NMDhcpConfig                  *dhcp6_config);
+                                                      NMDhcpConfig                  *dhcp6_config,
+                                                      gboolean                       generic);
 
 void nm_config_device_state_prune_stale(GHashTable *preserve_ifindexes,
                                         NMPlatform *preserve_in_platform);

src/core/nm-manager.c

@@ -4213,8 +4213,12 @@ platform_link_added(NMManager                     *self,
     }
 
 add:
-    /* Try registered device factories */
+    if (dev_state && dev_state->generic_sw) {
-    factory = nm_device_factory_manager_find_factory_for_link_type(plink->type);
+        factory = nm_device_factory_get_generic_factory();
+    } else {
+        /* Try registered device factories */
+        factory = nm_device_factory_manager_find_factory_for_link_type(plink->type);
+    }
     if (factory) {
         gboolean              ignore = FALSE;
         gs_free_error GError *error  = NULL;
@@ -7860,7 +7864,10 @@ nm_manager_write_device_state(NMManager *self, NMDevice *device, int *out_ifinde
                                       route_metric_default_aspired,
                                       route_metric_default_effective,
                                       nm_device_get_dhcp_config(device, AF_INET),
-                                      nm_device_get_dhcp_config(device, AF_INET6)))
+                                      nm_device_get_dhcp_config(device, AF_INET6),
+                                      nm_device_is_software(device)
+                                          && nm_device_get_device_type(device)
+                                                 == NM_DEVICE_TYPE_GENERIC))
         return FALSE;
 
     NM_SET_OUT(out_ifindex, ifindex);