core,nmcli: merge branch 'th/limit-routes-addresses'

See-also: https://github.com/firewalld/firewalld/issues/1232

https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1799

NEWS

@@ -15,6 +15,10 @@ Overview of changes since NetworkManager-1.44
 * Honor udev property ID_NET_MANAGED_BY to only manage an interface
   when set to "org.freedesktop.NetworkManager".
 * Drop build support with Python2. Python3 is now required.
+* nmcli: limit number of printed addresses/routes in `nmcli` overview to 10.
+* Limit number of exported IP addresses/routes on D-Bus to 100 to reduce
+  performance cost. Also, D-Bus updates for addresses/routes are now rate
+  limited to 3 per second.
 
 =============================================
 NetworkManager-1.44

src/core/NetworkManagerUtils.c

@@ -1558,7 +1558,8 @@ nm_utils_ip_addresses_to_dbus(int                          addr_family,
     char             addr_str[NM_INET_ADDRSTRLEN];
     NMDedupMultiIter iter;
     const NMPObject *obj;
-    guint            i;
+    const gsize      MAX_ADDRESSES = 100;
+    gsize            i;
 
     nm_assert_addr_family(addr_family);
 
@@ -1580,6 +1581,11 @@ nm_utils_ip_addresses_to_dbus(int                          addr_family,
         nm_platform_dedup_multi_iter_next_obj(&iter, &obj, NMP_OBJECT_TYPE_IP_ADDRESS(IS_IPv4))) {
         const NMPlatformIPXAddress *address = NMP_OBJECT_CAST_IPX_ADDRESS(obj);
 
+        if (i > MAX_ADDRESSES) {
+            /* Limited. The rest is hidden. */
+            break;
+        }
+
         if (out_address_data) {
             GVariantBuilder addr_builder;
             gconstpointer   p;
@@ -1669,6 +1675,8 @@ nm_utils_ip_routes_to_dbus(int                          addr_family,
     GVariantBuilder  builder_data;
     GVariantBuilder  builder_legacy;
     char             addr_str[NM_INET_ADDRSTRLEN];
+    const gsize      MAX_ROUTES = 100;
+    gsize            i;
 
     nm_assert_addr_family(addr_family);
 
@@ -1681,6 +1689,7 @@ nm_utils_ip_routes_to_dbus(int                          addr_family,
             g_variant_builder_init(&builder_legacy, G_VARIANT_TYPE("a(ayuayu)"));
     }
 
+    i = 0;
     nm_dedup_multi_iter_init(&iter, head_entry);
     while (nm_platform_dedup_multi_iter_next_obj(&iter, &obj, NMP_OBJECT_TYPE_IP_ROUTE(IS_IPv4))) {
         const NMPlatformIPXRoute *r = NMP_OBJECT_CAST_IPX_ROUTE(obj);
@@ -1699,6 +1708,13 @@ nm_utils_ip_routes_to_dbus(int                          addr_family,
         if (r->rx.type_coerced != nm_platform_route_type_coerce(RTN_UNICAST))
             continue;
 
+        if (i >= MAX_ROUTES) {
+            /* Limited. The rest is hidden. */
+            break;
+        }
+
+        i++;
+
         if (out_route_data) {
             GVariantBuilder route_builder;
             gconstpointer   gateway;

src/core/nm-ip-config.c

@@ -16,6 +16,10 @@
 
 /*****************************************************************************/
 
+#define NOTIFY_PLATFORM_RATELIMIT_MSEC 333
+
+/*****************************************************************************/
+
 GType nm_ip4_config_get_type(void);
 GType nm_ip6_config_get_type(void);
 
@@ -67,6 +71,73 @@ _value_set_variant_as(GValue *value, const char *const *strv, guint len)
 
 /*****************************************************************************/
 
+static void
+_notify_platform_handle(NMIPConfig *self, gint64 now_msec)
+{
+    NMIPConfigPrivate *priv = NM_IP_CONFIG_GET_PRIVATE(self);
+    guint32            obj_type_flags;
+
+    nm_clear_g_source_inst(&priv->notify_platform_timeout_source);
+
+    priv->notify_platform_rlimited_until_msec = now_msec + NOTIFY_PLATFORM_RATELIMIT_MSEC;
+
+    obj_type_flags = nm_steal_int(&priv->notify_platform_obj_type_flags);
+
+    nm_assert(obj_type_flags != 0u);
+
+    _handle_platform_change(self, obj_type_flags, FALSE);
+}
+
+static gboolean
+_notify_platform_cb(gpointer user_data)
+{
+    _notify_platform_handle(user_data, nm_utils_get_monotonic_timestamp_msec());
+    return G_SOURCE_CONTINUE;
+}
+
+static void
+_notify_platform(NMIPConfig *self, guint32 obj_type_flags)
+{
+    const int          addr_family = nm_ip_config_get_addr_family(self);
+    const int          IS_IPv4     = NM_IS_IPv4(addr_family);
+    NMIPConfigPrivate *priv        = NM_IP_CONFIG_GET_PRIVATE(self);
+    gint64             now_msec;
+
+    obj_type_flags &= (nmp_object_type_to_flags(NMP_OBJECT_TYPE_IP_ADDRESS(IS_IPv4))
+                       | nmp_object_type_to_flags(NMP_OBJECT_TYPE_IP_ROUTE(IS_IPv4)));
+
+    if (obj_type_flags == 0u)
+        return;
+
+    priv->notify_platform_obj_type_flags |= obj_type_flags;
+
+    if (priv->notify_platform_timeout_source) {
+        /* We are currently rate limited. Don't bother to check whether
+         * (now_msec < priv->notify_platform_rlimited_until_msec), just always
+         * delegate to the timeout handler. It is scheduled with a lower idle
+         * priority, so we want that additional backoff. */
+        return;
+    }
+
+    now_msec = nm_utils_get_monotonic_timestamp_msec();
+
+    if (now_msec < priv->notify_platform_rlimited_until_msec) {
+        priv->notify_platform_timeout_source = nm_g_source_attach(
+            /* Schedule with a low G_PRIORITY_LOW. */
+            nm_g_timeout_source_new(priv->notify_platform_rlimited_until_msec - now_msec,
+                                    G_PRIORITY_LOW - 10,
+                                    _notify_platform_cb,
+                                    self,
+                                    NULL),
+            NULL);
+        return;
+    }
+
+    _notify_platform_handle(self, now_msec);
+}
+
+/*****************************************************************************/
+
 static void
 _l3cfg_notify_cb(NML3Cfg *l3cfg, const NML3ConfigNotifyData *notify_data, NMIPConfig *self)
 {
@@ -76,7 +147,7 @@ _l3cfg_notify_cb(NML3Cfg *l3cfg, const NML3ConfigNotifyData *notify_data, NMIPCo
             _handle_l3cd_changed(self, notify_data->l3cd_changed.l3cd_new);
         break;
     case NM_L3_CONFIG_NOTIFY_TYPE_PLATFORM_CHANGE_ON_IDLE:
-        _handle_platform_change(self, notify_data->platform_change_on_idle.obj_type_flags, FALSE);
+        _notify_platform(self, notify_data->platform_change_on_idle.obj_type_flags);
         break;
     default:
         break;
@@ -207,6 +278,8 @@ finalize(GObject *object)
     NMIPConfig        *self = NM_IP_CONFIG(object);
     NMIPConfigPrivate *priv = NM_IP_CONFIG_GET_PRIVATE(self);
 
+    nm_clear_g_source_inst(&priv->notify_platform_timeout_source);
+
     nm_clear_g_signal_handler(priv->l3cfg, &priv->l3cfg_notify_id);
 
     g_object_unref(priv->l3cfg);

src/core/nm-ip-config.h

@@ -32,7 +32,10 @@ struct _NMIPConfigPrivate {
     struct {
         const NMPObject *best_default_route;
     } v_gateway;
-    gulong l3cfg_notify_id;
+    GSource *notify_platform_timeout_source;
+    gint64   notify_platform_rlimited_until_msec;
+    gulong   l3cfg_notify_id;
+    guint32  notify_platform_obj_type_flags;
 };
 
 struct _NMIPConfig {

src/nmcli/general.c

@@ -1411,36 +1411,57 @@ device_overview(NmCli *nmc, NMDevice *device)
 static void
 ac_overview(NmCli *nmc, NMActiveConnection *ac)
 {
-    GString                 *outbuf = g_string_sized_new(80);
+    nm_auto_str_buf NMStrBuf str = NM_STR_BUF_INIT_A(NM_UTILS_GET_NEXT_REALLOC_SIZE_488, FALSE);
-    NMIPConfig              *ip;
+    const guint              MAX_ADDRESSES = 10;
-    nm_auto_str_buf NMStrBuf str = NM_STR_BUF_INIT(NM_UTILS_GET_NEXT_REALLOC_SIZE_104, FALSE);
+    const guint              MAX_ROUTES    = 10;
+    int                      IS_IPv4;
 
     if (nm_active_connection_get_controller(ac)) {
-        g_string_append_printf(outbuf,
+        nm_str_buf_append_printf(&str,
-                               "%s %s, ",
+                                 "%s %s, ",
-                               _("master"),
+                                 _("master"),
-                               nm_device_get_iface(nm_active_connection_get_controller(ac)));
+                                 nm_device_get_iface(nm_active_connection_get_controller(ac)));
     }
     if (nm_active_connection_get_vpn(ac))
-        g_string_append_printf(outbuf, "%s, ", _("VPN"));
+        nm_str_buf_append_printf(&str, "%s, ", _("VPN"));
     if (nm_active_connection_get_default(ac))
-        g_string_append_printf(outbuf, "%s, ", _("ip4 default"));
+        nm_str_buf_append_printf(&str, "%s, ", _("ip4 default"));
     if (nm_active_connection_get_default6(ac))
-        g_string_append_printf(outbuf, "%s, ", _("ip6 default"));
+        nm_str_buf_append_printf(&str, "%s, ", _("ip6 default"));
-    if (outbuf->len >= 2) {
+    if (str.len >= 2) {
-        g_string_truncate(outbuf, outbuf->len - 2);
+        nm_str_buf_set_size(&str, str.len - 2u, TRUE, FALSE);
-        nmc_print("\t%s\n", outbuf->str);
+        nmc_print("\t%s\n", nm_str_buf_get_str(&str));
     }
 
-    ip = nm_active_connection_get_ip4_config(ac);
+    nm_str_buf_reset(&str);
-    if (ip) {
+
+    for (IS_IPv4 = 1; IS_IPv4 >= 0; IS_IPv4--) {
+        NMIPConfig      *ip;
         const GPtrArray *p;
-        int              i;
+        guint            i;
+
+        ip = IS_IPv4 ? nm_active_connection_get_ip4_config(ac)
+                     : nm_active_connection_get_ip6_config(ac);
+        if (!ip)
+            continue;
 
         p = nm_ip_config_get_addresses(ip);
         for (i = 0; i < p->len; i++) {
             NMIPAddress *a = p->pdata[i];
-            nmc_print("\tinet4 %s/%d\n", nm_ip_address_get_address(a), nm_ip_address_get_prefix(a));
+
+            nmc_print("\tinet%c %s/%d\n",
+                      IS_IPv4 ? '4' : '6',
+                      nm_ip_address_get_address(a),
+                      nm_ip_address_get_prefix(a));
+
+            if (i >= MAX_ADDRESSES - 1u && p->len - i > 2u) {
+                /* Print always at least MAX_ADDRESSES fully.
+                 * If there are MAX_ADDRESSES+1 addresses, print them all fully.
+                 * If there are more addresses, print MAX_ADDRESSES fully, and a
+                 * "more" line. */
+                nmc_print("\tinet%c ... more\n", IS_IPv4 ? '4' : '6');
+                break;
+            }
         }
 
         p = nm_ip_config_get_routes(ip);
@@ -1450,33 +1471,14 @@ ac_overview(NmCli *nmc, NMActiveConnection *ac)
             nm_str_buf_reset(&str);
             _nm_ip_route_to_string(a, &str);
 
-            nmc_print("\troute4 %s\n", nm_str_buf_get_str(&str));
+            nmc_print("\troute%c %s\n", IS_IPv4 ? '4' : '6', nm_str_buf_get_str(&str));
+
+            if (i >= MAX_ROUTES - 1u && p->len - i > 2u) {
+                nmc_print("\troute%c ... more\n", IS_IPv4 ? '4' : '6');
+                break;
+            }
         }
     }
-
-    ip = nm_active_connection_get_ip6_config(ac);
-    if (ip) {
-        const GPtrArray *p;
-        int              i;
-
-        p = nm_ip_config_get_addresses(ip);
-        for (i = 0; i < p->len; i++) {
-            NMIPAddress *a = p->pdata[i];
-            nmc_print("\tinet6 %s/%d\n", nm_ip_address_get_address(a), nm_ip_address_get_prefix(a));
-        }
-
-        p = nm_ip_config_get_routes(ip);
-        for (i = 0; i < p->len; i++) {
-            NMIPRoute *a = p->pdata[i];
-
-            nm_str_buf_reset(&str);
-            _nm_ip_route_to_string(a, &str);
-
-            nmc_print("\troute6 %s\n", nm_str_buf_get_str(&str));
-        }
-    }
-
-    g_string_free(outbuf, TRUE);
 }
 
 void