core: add support for reading global DNS configuration from keyfile

Add to the NMConfigData object information about global DNS
configuration, which is loaded from user or internal keyfile upon
object construction.

src/nm-config-data.c

@@ -72,10 +72,25 @@ typedef struct {
 	char *dns_mode;
 	char *rc_manager;
 
+	NMGlobalDnsConfig *global_dns;
+
 	/* mutable field */
 	char *value_cached;
 } NMConfigDataPrivate;
 
+struct _NMGlobalDnsDomain {
+	char *name;
+	char **servers;
+	char **options;
+};
+
+struct _NMGlobalDnsConfig {
+	char **searches;
+	char **options;
+	GHashTable *domains;
+	char **domain_list;
+	gboolean internal;
+};
 
 enum {
 	PROP_0,
@@ -91,6 +106,7 @@ enum {
 	LAST_PROP
 };
 
+
 G_DEFINE_TYPE (NMConfigData, nm_config_data, G_TYPE_OBJECT)
 
 #define NM_CONFIG_DATA_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), NM_TYPE_CONFIG_DATA, NMConfigDataPrivate))
@@ -534,6 +550,279 @@ nm_config_data_log (const NMConfigData *self, const char *prefix)
 
 /************************************************************************/
 
+const char *const *
+nm_global_dns_config_get_searches (const NMGlobalDnsConfig *dns)
+{
+	g_return_val_if_fail (dns, NULL);
+
+	return (const char *const *) dns->searches;
+}
+
+const char *const *
+nm_global_dns_config_get_options (const NMGlobalDnsConfig *dns)
+{
+	g_return_val_if_fail (dns, NULL);
+
+	return (const char *const *) dns->options;
+}
+
+guint
+nm_global_dns_config_get_num_domains (const NMGlobalDnsConfig *dns)
+{
+	g_return_val_if_fail (dns, 0);
+	g_return_val_if_fail (dns->domains, 0);
+
+	return g_hash_table_size (dns->domains);
+}
+
+NMGlobalDnsDomain *
+nm_global_dns_config_get_domain (const NMGlobalDnsConfig *dns, guint i)
+{
+	NMGlobalDnsDomain *domain;
+
+	g_return_val_if_fail (dns, NULL);
+	g_return_val_if_fail (dns->domains, NULL);
+	g_return_val_if_fail (dns->domain_list, NULL);
+	g_return_val_if_fail (i < g_strv_length (dns->domain_list), NULL);
+
+	domain = g_hash_table_lookup (dns->domains, dns->domain_list[i]);
+	g_return_val_if_fail (domain, NULL);
+
+	return domain;
+}
+
+NMGlobalDnsDomain *nm_global_dns_config_lookup_domain (const NMGlobalDnsConfig *dns, const char *name)
+{
+	g_return_val_if_fail (dns, NULL);
+	g_return_val_if_fail (dns->domains, NULL);
+	g_return_val_if_fail (name, NULL);
+
+	return g_hash_table_lookup (dns->domains, name);
+}
+
+const char *
+nm_global_dns_domain_get_name (const NMGlobalDnsDomain *domain)
+{
+	g_return_val_if_fail (domain, NULL);
+
+	return (const char *) domain->name;
+}
+
+const char *const *
+nm_global_dns_domain_get_servers (const NMGlobalDnsDomain *domain)
+{
+	g_return_val_if_fail (domain, NULL);
+
+	return (const char *const *) domain->servers;
+}
+
+const char *const *
+nm_global_dns_domain_get_options (const NMGlobalDnsDomain *domain)
+{
+	g_return_val_if_fail (domain, NULL);
+	return (const char *const *) domain->options;
+}
+
+gboolean
+nm_global_dns_config_is_internal (const NMGlobalDnsConfig *dns)
+{
+	return dns->internal;
+}
+
+gboolean
+nm_global_dns_config_is_empty (const NMGlobalDnsConfig *dns)
+{
+	g_return_val_if_fail (dns, TRUE);
+	g_return_val_if_fail (dns->domains, TRUE);
+
+	return    (!dns->searches || g_strv_length (dns->searches) == 0)
+	       && (!dns->options || g_strv_length (dns->options) == 0)
+	       && g_hash_table_size (dns->domains) == 0;
+}
+
+static void
+global_dns_domain_free (NMGlobalDnsDomain  *domain)
+{
+	if (domain) {
+		g_free (domain->name);
+		g_strfreev (domain->servers);
+		g_strfreev (domain->options);
+		g_free (domain);
+	}
+}
+
+void
+nm_global_dns_config_free (NMGlobalDnsConfig *conf)
+{
+	if (conf) {
+		g_strfreev (conf->searches);
+		g_strfreev (conf->options);
+		g_free (conf->domain_list);
+		g_hash_table_unref (conf->domains);
+		g_free (conf);
+	}
+}
+
+NMGlobalDnsConfig *
+nm_config_data_get_global_dns_config (const NMConfigData *self)
+{
+	g_return_val_if_fail (NM_IS_CONFIG_DATA (self), NULL);
+
+	return NM_CONFIG_DATA_GET_PRIVATE (self)->global_dns;
+}
+
+static void
+global_dns_config_update_domain_list (NMGlobalDnsConfig *dns)
+{
+	guint length;
+
+	g_free (dns->domain_list);
+	dns->domain_list = (char **) g_hash_table_get_keys_as_array (dns->domains, &length);
+}
+
+static NMGlobalDnsConfig *
+load_global_dns (GKeyFile *keyfile, gboolean internal)
+{
+	NMGlobalDnsConfig *conf;
+	char *group, *domain_prefix;
+	gs_strfreev char **groups = NULL;
+	int g, i, j, domain_prefix_len;
+	gboolean default_found = FALSE;
+	char **strv;
+
+	group = internal
+	        ? NM_CONFIG_KEYFILE_GROUP_INTERN_GLOBAL_DNS
+	        : NM_CONFIG_KEYFILE_GROUP_GLOBAL_DNS;
+	domain_prefix = internal
+	                ? NM_CONFIG_KEYFILE_GROUPPREFIX_INTERN_GLOBAL_DNS_DOMAIN
+	                : NM_CONFIG_KEYFILE_GROUPPREFIX_GLOBAL_DNS_DOMAIN;
+	domain_prefix_len = strlen (domain_prefix);
+
+	if (!keyfile || !nm_config_keyfile_get_boolean (keyfile, group, NM_CONFIG_KEYFILE_KEY_GLOBAL_DNS_ENABLE, FALSE))
+		return NULL;
+
+	conf = g_malloc0 (sizeof (NMGlobalDnsConfig));
+	conf->domains = g_hash_table_new_full (g_str_hash, g_str_equal,
+	                                       g_free, (GDestroyNotify) global_dns_domain_free);
+
+	strv = g_key_file_get_string_list (keyfile, group, "searches", NULL, NULL);
+	if (strv)
+		conf->searches = _nm_utils_strv_cleanup (strv, TRUE, TRUE, TRUE);
+
+	strv = g_key_file_get_string_list (keyfile, group, "options", NULL, NULL);
+	if (strv) {
+		_nm_utils_strv_cleanup (strv, TRUE, TRUE, TRUE);
+		for (i = 0, j = 0; strv[i]; i++) {
+			if (_nm_utils_dns_option_validate (strv[i], NULL, NULL, TRUE, NULL))
+				strv[j++] = strv[i];
+			else
+				g_free (strv[i]);
+		}
+		strv[j] = NULL;
+		conf->options = strv;
+	}
+
+	groups = g_key_file_get_groups (keyfile, NULL);
+	for (g = 0; groups[g]; g++) {
+		char *name;
+		char **servers = NULL, **options = NULL;
+		NMGlobalDnsDomain *domain;
+
+		if (   !g_str_has_prefix (groups[g], domain_prefix)
+		    || !groups[g][domain_prefix_len])
+			continue;
+
+		strv = g_key_file_get_string_list (keyfile, groups[g], "servers", NULL, NULL);
+		if (strv) {
+			_nm_utils_strv_cleanup (strv, TRUE, TRUE, TRUE);
+			for (i = 0, j = 0; strv[i]; i++) {
+				if (   nm_utils_ipaddr_valid (AF_INET, strv[i])
+				    || nm_utils_ipaddr_valid (AF_INET6, strv[i]))
+					strv[j++] = strv[i];
+				else
+					g_free (strv[i]);
+			}
+			if (j) {
+				strv[j] = NULL;
+				servers = strv;
+			}
+			else
+				g_free (strv);
+		}
+
+		if (!servers)
+			continue;
+
+		strv = g_key_file_get_string_list (keyfile, groups[g], "options", NULL, NULL);
+		if (strv)
+			options = _nm_utils_strv_cleanup (strv, TRUE, TRUE, TRUE);
+
+		name = strdup (&groups[g][domain_prefix_len]);
+		domain = g_malloc0 (sizeof (NMGlobalDnsDomain));
+		domain->name = name;
+		domain->servers = servers;
+		domain->options = options;
+
+		g_hash_table_insert (conf->domains, strdup (name), domain);
+
+		if (!strcmp (name, "*"))
+			default_found = TRUE;
+	}
+
+	if (!default_found) {
+		nm_log_dbg (LOGD_CORE, "%s global DNS configuration is missing default domain, ignore it",
+		            internal ? "internal" : "user");
+		nm_global_dns_config_free (conf);
+		return NULL;
+	}
+
+	conf->internal = internal;
+	global_dns_config_update_domain_list (conf);
+	return conf;
+}
+
+static gboolean
+global_dns_equal (NMGlobalDnsConfig *old, NMGlobalDnsConfig *new)
+{
+	NMGlobalDnsDomain *domain_old, *domain_new;
+	gpointer key, value_old, value_new;
+	GHashTableIter iter;
+
+	if (old == new)
+		return TRUE;
+
+	if (!old || !new)
+		return FALSE;
+
+	if (   !_nm_utils_strv_equal (old->options, new->options)
+	    || !_nm_utils_strv_equal (old->searches, new->searches))
+		return FALSE;
+
+	if ((!old->domains || !new->domains) && old->domains != new->domains)
+		return FALSE;
+
+	if (g_hash_table_size (old->domains) != g_hash_table_size (new->domains))
+		return FALSE;
+
+	g_hash_table_iter_init (&iter, old->domains);
+	while (g_hash_table_iter_next (&iter, &key, &value_old)) {
+		value_new = g_hash_table_lookup (new->domains, key);
+		if (!value_new)
+			return FALSE;
+
+		domain_old = value_old;
+		domain_new = value_new;
+
+		if (   !_nm_utils_strv_equal (domain_old->options, domain_new->options)
+		    || !_nm_utils_strv_equal (domain_old->servers, domain_new->servers))
+			return FALSE;
+	}
+
+	return TRUE;
+}
+
+/************************************************************************/
+
 char *
 nm_config_data_get_connection_default (const NMConfigData *self,
                                        const char *property,
@@ -683,6 +972,9 @@ nm_config_data_diff (NMConfigData *old_data, NMConfigData *new_data)
 	if (g_strcmp0 (nm_config_data_get_rc_manager (old_data), nm_config_data_get_rc_manager (new_data)))
 		changes |= NM_CONFIG_CHANGE_RC_MANAGER;
 
+	if (!global_dns_equal (priv_old->global_dns, priv_new->global_dns))
+		changes |= NM_CONFIG_CHANGE_GLOBAL_DNS_CONFIG;
+
 	return changes;
 }
 
@@ -804,6 +1096,8 @@ finalize (GObject *gobject)
 	g_slist_free_full (priv->ignore_carrier, g_free);
 	g_slist_free_full (priv->assume_ipv6ll_only, g_free);
 
+	nm_global_dns_config_free (priv->global_dns);
+
 	if (priv->connection_infos) {
 		for (i = 0; priv->connection_infos[i].group_name; i++) {
 			g_free (priv->connection_infos[i].group_name);
@@ -858,6 +1152,10 @@ constructed (GObject *object)
 
 	priv->no_auto_default.specs_config = nm_config_get_device_match_spec (priv->keyfile, NM_CONFIG_KEYFILE_GROUP_MAIN, "no-auto-default", NULL);
 
+	priv->global_dns = load_global_dns (priv->keyfile_user, FALSE);
+	if (!priv->global_dns)
+		priv->global_dns = load_global_dns (priv->keyfile_intern, TRUE);
+
 	G_OBJECT_CLASS (nm_config_data_parent_class)->constructed (object);
 }
 

src/nm-config-data.h

@@ -76,6 +76,7 @@ typedef enum { /*< flags >*/
 	NM_CONFIG_CHANGE_NO_AUTO_DEFAULT           = (1L << 8),
 	NM_CONFIG_CHANGE_DNS_MODE                  = (1L << 9),
 	NM_CONFIG_CHANGE_RC_MANAGER                = (1L << 10),
+	NM_CONFIG_CHANGE_GLOBAL_DNS_CONFIG         = (1L << 11),
 
 	_NM_CONFIG_CHANGE_LAST,
 	NM_CONFIG_CHANGE_ALL                       = ((_NM_CONFIG_CHANGE_LAST - 1) << 1) - 1,
@@ -89,6 +90,9 @@ typedef struct {
 	GObjectClass parent;
 } NMConfigDataClass;
 
+typedef struct _NMGlobalDnsConfig NMGlobalDnsConfig;
+typedef struct _NMGlobalDnsDomain NMGlobalDnsDomain;
+
 GType nm_config_data_get_type (void);
 
 NMConfigData *nm_config_data_new (const char *config_main_file,
@@ -124,6 +128,7 @@ const char *nm_config_data_get_rc_manager (const NMConfigData *self);
 
 gboolean nm_config_data_get_ignore_carrier (const NMConfigData *self, NMDevice *device);
 gboolean nm_config_data_get_assume_ipv6ll_only (const NMConfigData *self, NMDevice *device);
+NMGlobalDnsConfig *nm_config_data_get_global_dns_config (const NMConfigData *self);
 
 char *nm_config_data_get_connection_default (const NMConfigData *self,
                                              const char *property,
@@ -135,6 +140,18 @@ gboolean nm_config_data_is_intern_atomic_group (const NMConfigData *self, const
 
 GKeyFile *nm_config_data_clone_keyfile_intern (const NMConfigData *self);
 
+const char *const *nm_global_dns_config_get_searches (const NMGlobalDnsConfig *dns);
+const char *const *nm_global_dns_config_get_options (const NMGlobalDnsConfig *dns);
+guint nm_global_dns_config_get_num_domains (const NMGlobalDnsConfig *dns);
+NMGlobalDnsDomain *nm_global_dns_config_get_domain (const NMGlobalDnsConfig *dns, guint i);
+NMGlobalDnsDomain *nm_global_dns_config_lookup_domain (const NMGlobalDnsConfig *dns, const char *name);
+const char *nm_global_dns_domain_get_name (const NMGlobalDnsDomain *domain);
+const char *const *nm_global_dns_domain_get_servers (const NMGlobalDnsDomain *domain);
+const char *const *nm_global_dns_domain_get_options (const NMGlobalDnsDomain *domain);
+gboolean nm_global_dns_config_is_internal (const NMGlobalDnsConfig *dns);
+gboolean nm_global_dns_config_is_empty (const NMGlobalDnsConfig *dns);
+void nm_global_dns_config_free (NMGlobalDnsConfig *conf);
+
 /* private accessors */
 GKeyFile *_nm_config_data_get_keyfile (const NMConfigData *self);
 GKeyFile *_nm_config_data_get_keyfile_user (const NMConfigData *self);

src/nm-config.c

@@ -1184,6 +1184,24 @@ intern_config_read (const char *filename,
 	}
 
 out:
+	/*
+	 * If user configuration specifies global DNS options, the DNS
+	 * options in internal configuration must be deleted. Otherwise a
+	 * deletion of options from user configuration may cause the
+	 * internal options to appear again.
+	 */
+	if (nm_config_keyfile_get_boolean (keyfile_conf, NM_CONFIG_KEYFILE_GROUP_GLOBAL_DNS, NM_CONFIG_KEYFILE_KEY_GLOBAL_DNS_ENABLE, FALSE)) {
+		if (g_key_file_remove_group (keyfile_intern, NM_CONFIG_KEYFILE_GROUP_INTERN_GLOBAL_DNS, NULL))
+			needs_rewrite = TRUE;
+		for (g = 0; groups && groups[g]; g++) {
+			if (   g_str_has_prefix (groups[g], NM_CONFIG_KEYFILE_GROUPPREFIX_INTERN_GLOBAL_DNS_DOMAIN)
+			    && groups[g][STRLEN (NM_CONFIG_KEYFILE_GROUPPREFIX_INTERN_GLOBAL_DNS_DOMAIN)]) {
+				g_key_file_remove_group (keyfile_intern, groups[g], NULL);
+				needs_rewrite = TRUE;
+			}
+		}
+	}
+
 	g_key_file_unref (keyfile);
 
 	if (out_needs_rewrite)
@@ -1593,6 +1611,8 @@ _change_flags_one_to_string (NMConfigChangeFlags flag)
 		return "dns-mode";
 	case NM_CONFIG_CHANGE_RC_MANAGER:
 		return "rc-manager";
+	case NM_CONFIG_CHANGE_GLOBAL_DNS_CONFIG:
+		return "global-dns-config";
 	default:
 		g_return_val_if_reached ("unknown");
 	}

src/nm-config.h

@@ -49,17 +49,20 @@ G_BEGIN_DECLS
 
 #define NM_CONFIG_KEYFILE_GROUPPREFIX_INTERN                ".intern."
 #define NM_CONFIG_KEYFILE_GROUPPREFIX_CONNECTION            "connection"
+#define NM_CONFIG_KEYFILE_GROUPPREFIX_GLOBAL_DNS_DOMAIN     "global-dns-domain-"
 #define NM_CONFIG_KEYFILE_GROUPPREFIX_TEST_APPEND_STRINGLIST ".test-append-stringlist"
 
 #define NM_CONFIG_KEYFILE_GROUP_MAIN                        "main"
 #define NM_CONFIG_KEYFILE_GROUP_LOGGING                     "logging"
 #define NM_CONFIG_KEYFILE_GROUP_CONNECTIVITY                "connectivity"
+#define NM_CONFIG_KEYFILE_GROUP_GLOBAL_DNS                  "global-dns"
 
 #define NM_CONFIG_KEYFILE_GROUP_KEYFILE                     "keyfile"
 #define NM_CONFIG_KEYFILE_GROUP_IFUPDOWN                    "ifupdown"
 #define NM_CONFIG_KEYFILE_GROUP_IFNET                       "ifnet"
 
 #define NM_CONFIG_KEYFILE_KEY_LOGGING_BACKEND               "backend"
+#define NM_CONFIG_KEYFILE_KEY_GLOBAL_DNS_ENABLE             "enable"
 #define NM_CONFIG_KEYFILE_KEY_ATOMIC_SECTION_WAS            ".was"
 #define NM_CONFIG_KEYFILE_KEY_IFNET_AUTO_REFRESH            "auto_refresh"
 #define NM_CONFIG_KEYFILE_KEY_IFNET_MANAGED                 "managed"
@@ -69,6 +72,11 @@ G_BEGIN_DECLS
 #define NM_CONFIG_KEYFILE_KEYPREFIX_WAS                     ".was."
 #define NM_CONFIG_KEYFILE_KEYPREFIX_SET                     ".set."
 
+#define NM_CONFIG_KEYFILE_GROUP_INTERN_GLOBAL_DNS \
+	NM_CONFIG_KEYFILE_GROUPPREFIX_INTERN NM_CONFIG_KEYFILE_GROUP_GLOBAL_DNS
+#define NM_CONFIG_KEYFILE_GROUPPREFIX_INTERN_GLOBAL_DNS_DOMAIN \
+	NM_CONFIG_KEYFILE_GROUPPREFIX_INTERN NM_CONFIG_KEYFILE_GROUPPREFIX_GLOBAL_DNS_DOMAIN
+
 typedef struct NMConfigCmdLineOptions NMConfigCmdLineOptions;
 
 struct _NMConfig {

src/tests/config/Makefile.am

@@ -30,6 +30,8 @@ TESTS = test-config
 EXTRA_DIST = \
 	NetworkManager.conf \
 	bad.conf \
+	global-dns-disabled.conf \
+	global-dns-invalid.conf \
 	conf.d/00-overrides.conf \
 	conf.d/10-more.conf \
 	conf.d/90-last.conf

src/tests/config/NetworkManager.conf

@@ -81,3 +81,19 @@ ord.key07=A-0.3.07
 ord.key08=A-0.3.08
 ord.key09=A-0.3.09
 ord.ovw01=A-0.3.ovw01
+
+[global-dns]
+enable=yes
+searches=foo.com,bar.org
+options=debug,edns0
+
+[global-dns-domain-*]
+servers=1.1.1.1,bad,1::128
+options=opt1,opt2
+
+[global-dns-domain-example.com]
+servers=2.2.2.2
+
+# Invalid section: 'servers' key is missing
+[global-dns-domain-test.com]
+options=opt3

src/tests/config/global-dns-disabled.conf

@@ -0,0 +1,8 @@
+[global-dns]
+enable=no
+searches=foo.com
+options=timeout:5
+
+[global-dns-domain-*]
+servers=1.2.3.4
+options=myoption

src/tests/config/global-dns-invalid.conf

@@ -0,0 +1,10 @@
+# Invalid configuration, since there isn't a default domain section
+
+[global-dns]
+enable=yes
+searches=foo.com
+options=timeout:5
+
+[global-dns-domain-test.com]
+servers=1.2.3.4
+options=myoption

src/tests/config/test-config.c

@@ -243,6 +243,83 @@ test_config_override (void)
 	g_object_unref (config);
 }
 
+static void
+test_config_global_dns (void)
+{
+	NMConfig *config;
+	const NMGlobalDnsConfig *dns;
+	NMGlobalDnsDomain *domain;
+	const char *const *strv;
+
+	config = setup_config (NULL, SRCDIR "/NetworkManager.conf", "", NULL,
+	                       "/no/such/dir", "", NULL);
+
+	dns = nm_config_data_get_global_dns_config (nm_config_get_data_orig (config));
+	g_assert (dns);
+
+	strv = nm_global_dns_config_get_searches (dns);
+	g_assert (strv);
+	g_assert_cmpuint (g_strv_length ((char **) strv), ==, 2);
+	g_assert_cmpstr (strv[0], ==, "foo.com");
+	g_assert_cmpstr (strv[1], ==, "bar.org");
+
+	strv = nm_global_dns_config_get_options (dns);
+	g_assert (strv);
+	g_assert_cmpuint (g_strv_length ((char **) strv), ==, 2);
+	g_assert_cmpstr (strv[0], ==, "debug");
+	g_assert_cmpstr (strv[1], ==, "edns0");
+
+	g_assert_cmpuint (nm_global_dns_config_get_num_domains (dns), ==, 2);
+
+	/* Default domain */
+	domain = nm_global_dns_config_lookup_domain (dns, "*");
+	g_assert (domain);
+
+	strv = nm_global_dns_domain_get_servers (domain);
+	g_assert (strv);
+	g_assert_cmpuint (g_strv_length ((char **) strv), ==, 2);
+	g_assert_cmpstr (strv[0], ==, "1.1.1.1");
+	g_assert_cmpstr (strv[1], ==, "1::128");
+
+	strv = nm_global_dns_domain_get_options (domain);
+	g_assert (strv);
+	g_assert_cmpuint (g_strv_length ((char **) strv), ==, 2);
+	g_assert_cmpstr (strv[0], ==, "opt1");
+	g_assert_cmpstr (strv[1], ==, "opt2");
+
+	/* 'example.com' domain */
+	domain = nm_global_dns_config_lookup_domain (dns, "example.com");
+	g_assert (domain);
+
+	strv = nm_global_dns_domain_get_servers (domain);
+	g_assert (strv);
+	g_assert_cmpuint (g_strv_length ((char **) strv), ==, 1);
+	g_assert_cmpstr (strv[0], ==, "2.2.2.2");
+
+	strv = nm_global_dns_domain_get_options (domain);
+	g_assert (!strv || g_strv_length ((char **) strv) == 0);
+
+	/* Non-existent domain 'test.com' */
+	domain = nm_global_dns_config_lookup_domain (dns, "test.com");
+	g_assert (!domain);
+
+	g_object_unref (config);
+
+	/* Check that a file without "enable=yes" gives a NULL configuration */
+	config = setup_config (NULL, SRCDIR "/global-dns-disabled.conf", "", NULL,
+	                       "/no/such/dir", "", NULL);
+	dns = nm_config_data_get_global_dns_config (nm_config_get_data_orig (config));
+	g_assert (!dns);
+	g_object_unref (config);
+
+	/* Check that a file without a default domain section gives a NULL configuration */
+	config = setup_config (NULL, SRCDIR "/global-dns-invalid.conf", "", NULL,
+	                       "/no/such/dir", "", NULL);
+	dns = nm_config_data_get_global_dns_config (nm_config_get_data_orig (config));
+	g_assert (!dns);
+	g_object_unref (config);
+}
+
 static void
 test_config_no_auto_default (void)
 {
@@ -852,6 +929,7 @@ main (int argc, char **argv)
 	g_test_add_func ("/config/confdir-parse-error", test_config_confdir_parse_error);
 
 	g_test_add_func ("/config/set-values", test_config_set_values);
+	g_test_add_func ("/config/global-dns", test_config_global_dns);
 
 	g_test_add_func ("/config/signal", test_config_signal);