core: capture DNS configuration from resolv.conf when generating connections (rh #1031763)

Ensures that resolv.conf is valid when assuming an already-configured device
that may have DNS information already written to resolv.conf.

https://bugzilla.redhat.com/show_bug.cgi?id=1031763

11 files changed, 459 insertions, 42 deletions

diff --git a/.gitignore b/.gitignore
index 63b992550c..50d14854cf 100644
--- a/.gitignore
+++ b/.gitignore
@@ -184,6 +184,7 @@ valgrind-*.log
 /src/tests/test-ip6-config
 /src/tests/test-policy-hosts
 /src/tests/test-wifi-ap-utils
+/src/tests/test-resolvconf-capture
 /src/dhcp-manager/tests/test-dhcp-dhclient
 /src/config/tests/test-config
 
diff --git a/src/NetworkManagerUtils.c b/src/NetworkManagerUtils.c
index c2cf5e7a50..4d42ad2d9d 100644
--- a/src/NetworkManagerUtils.c
+++ b/src/NetworkManagerUtils.c
@@ -25,6 +25,7 @@
 #include <string.h>
 #include <unistd.h>
 #include <stdlib.h>
+#include <resolv.h>
 
 #include "NetworkManagerUtils.h"
 #include "nm-utils.h"
@@ -611,3 +612,50 @@ nm_utils_new_vlan_name (const char *parent_iface, guint32 vlan_id)
 	return g_strdup_printf ("%s.%d", parent_iface, vlan_id);
 }
 
+/**
+ * nm_utils_read_resolv_conf_nameservers():
+ * @rc_contents: contents of a resolv.conf; or %NULL to read /etc/resolv.conf
+ *
+ * Reads all nameservers out of @rc_contents or /etc/resolv.conf and returns
+ * them.
+ *
+ * Returns: a #GPtrArray of 'char *' elements of each nameserver line from
+ * @contents or resolv.conf
+ */
+GPtrArray *
+nm_utils_read_resolv_conf_nameservers (const char *rc_contents)
+{
+	GPtrArray *nameservers = NULL;
+	char *contents = NULL;
+	char **lines, **iter;
+	char *p;
+
+	if (rc_contents)
+		contents = g_strdup (rc_contents);
+	else {
+		if (!g_file_get_contents (_PATH_RESCONF, &contents, NULL, NULL))
+			return NULL;
+	}
+
+	nameservers = g_ptr_array_new_full (3, g_free);
+
+	lines = g_strsplit_set (contents, "\r\n", -1);
+	for (iter = lines; *iter; iter++) {
+		if (!g_str_has_prefix (*iter, "nameserver"))
+			continue;
+		p = *iter + strlen ("nameserver");
+		if (!g_ascii_isspace (*p++))
+			continue;
+		/* Skip intermediate whitespace */
+		while (g_ascii_isspace (*p))
+			p++;
+		g_strchomp (p);
+
+		g_ptr_array_add (nameservers, g_strdup (p));
+	}
+	g_strfreev (lines);
+	g_free (contents);
+
+	return nameservers;
+}
+
diff --git a/src/NetworkManagerUtils.h b/src/NetworkManagerUtils.h
index 93ec11134d..a84ba10741 100644
--- a/src/NetworkManagerUtils.h
+++ b/src/NetworkManagerUtils.h
@@ -84,4 +84,6 @@ void nm_utils_complete_generic (NMConnection *connection,
 
 char *nm_utils_new_vlan_name (const char *parent_iface, guint32 vlan_id);
 
+GPtrArray *nm_utils_read_resolv_conf_nameservers (const char *rc_contents);
+
 #endif /* NETWORK_MANAGER_UTILS_H */
diff --git a/src/devices/nm-device.c b/src/devices/nm-device.c
index 832a959304..d92a94b28a 100644
--- a/src/devices/nm-device.c
+++ b/src/devices/nm-device.c
@@ -357,7 +357,7 @@ static void link_changed_cb (NMPlatform *platform, int ifindex, NMPlatformLink *
 static void check_carrier (NMDevice *device);
 
 static void nm_device_queued_ip_config_change_clear (NMDevice *self);
-static void update_ip_config (NMDevice *self, gboolean capture_dhcp);
+static void update_ip_config (NMDevice *self, gboolean initial);
 static void device_ip_changed (NMPlatform *platform, int ifindex, gpointer platform_object, NMPlatformReason reason, gpointer user_data);
 
 static void nm_device_slave_notify_enslave (NMDevice *dev, gboolean success);
@@ -6503,7 +6503,7 @@ capture_lease_config (NMDevice *device,
 }
 
 static void
-update_ip_config (NMDevice *self, gboolean capture_dhcp)
+update_ip_config (NMDevice *self, gboolean initial)
 {
 	NMDevicePrivate *priv = NM_DEVICE_GET_PRIVATE (self);
 	int ifindex;
@@ -6515,10 +6515,10 @@ update_ip_config (NMDevice *self, gboolean capture_dhcp)
 
 	/* IPv4 */
 	g_clear_object (&priv->ext_ip4_config);
-	priv->ext_ip4_config = nm_ip4_config_capture (ifindex);
+	priv->ext_ip4_config = nm_ip4_config_capture (ifindex, initial);
 
 	if (priv->ext_ip4_config) {
-		if (capture_dhcp) {
+		if (initial) {
 			g_clear_object (&priv->dev_ip4_config);
 			capture_lease_config (self, priv->ext_ip4_config, &priv->dev_ip4_config, NULL, NULL);
 		}
@@ -6532,7 +6532,7 @@ update_ip_config (NMDevice *self, gboolean capture_dhcp)
 
 	/* IPv6 */
 	g_clear_object (&priv->ext_ip6_config);
-	priv->ext_ip6_config = nm_ip6_config_capture (ifindex);
+	priv->ext_ip6_config = nm_ip6_config_capture (ifindex, initial);
 	if (priv->ext_ip6_config) {
 
 		/* Check this before modifying ext_ip6_config */
diff --git a/src/nm-ip4-config.c b/src/nm-ip4-config.c
index 5229ef9822..7aff888c0d 100644
--- a/src/nm-ip4-config.c
+++ b/src/nm-ip4-config.c
@@ -29,6 +29,7 @@
 #include "nm-dbus-manager.h"
 #include "nm-dbus-glib-types.h"
 #include "nm-ip4-config-glue.h"
+#include "NetworkManagerUtils.h"
 
 
 G_DEFINE_TYPE (NMIP4Config, nm_ip4_config, G_TYPE_OBJECT)
@@ -111,6 +112,52 @@ same_prefix (guint32 address1, guint32 address2, int plen)
 
 /******************************************************************/
 
+/**
+ * nm_ip4_config_capture_resolv_conf():
+ * @nameservers: array of guint32
+ * @rc_contents: the contents of a resolv.conf or %NULL to read /etc/resolv.conf
+ *
+ * Reads all resolv.conf IPv6 nameservers and adds them to @nameservers.
+ *
+ * Returns: %TRUE if nameservers were added, %FALSE if @nameservers is unchanged
+ */
+gboolean
+nm_ip4_config_capture_resolv_conf (GArray *nameservers,
+                                   const char *rc_contents)
+{
+	GPtrArray *read_ns;
+	guint i, j;
+	gboolean changed = FALSE;
+
+	g_return_val_if_fail (nameservers != NULL, FALSE);
+
+	read_ns = nm_utils_read_resolv_conf_nameservers (rc_contents);
+	if (!read_ns)
+		return FALSE;
+
+	for (i = 0; i < read_ns->len; i++) {
+		const char *s = g_ptr_array_index (read_ns, i);
+		guint32 ns = 0;
+
+		if (!inet_pton (AF_INET, s, (void *) &ns) || !ns)
+			continue;
+
+		/* Ignore duplicates */
+		for (j = 0; j < nameservers->len; j++) {
+			if (g_array_index (nameservers, guint32, j) == ns)
+				break;
+		}
+
+		if (j == nameservers->len) {
+			g_array_append_val (nameservers, ns);
+			changed = TRUE;
+		}
+	}
+
+	g_ptr_array_unref (read_ns);
+	return changed;
+}
+
 static gboolean
 addresses_are_duplicate (const NMPlatformIP4Address *a, const NMPlatformIP4Address *b, gboolean consider_plen)
 {
@@ -125,12 +172,14 @@ routes_are_duplicate (const NMPlatformIP4Route *a, const NMPlatformIP4Route *b,
 }
 
 NMIP4Config *
-nm_ip4_config_capture (int ifindex)
+nm_ip4_config_capture (int ifindex, gboolean capture_resolv_conf)
 {
 	NMIP4Config *config;
 	NMIP4ConfigPrivate *priv;
 	guint i;
-	gboolean gateway_changed = FALSE;
+	guint lowest_metric = G_MAXUINT;
+	guint32 old_gateway = 0;
+	gboolean has_gateway = FALSE;
 
 	/* Slaves have no IP configuration */
 	if (nm_platform_link_get_master (ifindex) > 0)
@@ -146,24 +195,34 @@ nm_ip4_config_capture (int ifindex)
 	priv->routes = nm_platform_ip4_route_get_all (ifindex, TRUE);
 
 	/* Extract gateway from default route */
+	old_gateway = priv->gateway;
 	for (i = 0; i < priv->routes->len; i++) {
 		const NMPlatformIP4Route *route = &g_array_index (priv->routes, NMPlatformIP4Route, i);
 
 		if (route->network == 0) {
-			if (priv->gateway != route->gateway) {
+			if (route->metric < lowest_metric) {
 				priv->gateway = route->gateway;
-				gateway_changed = TRUE;
+				lowest_metric = route->metric;
 			}
+			has_gateway = TRUE;
 			/* Remove the default route from the list */
 			g_array_remove_index (priv->routes, i);
-			break;
+			i--;
 		}
 	}
 
+	/* If the interface has the default route, and has IPv4 addresses, capture
+	 * nameservers from /etc/resolv.conf.
+	 */
+	if (priv->addresses->len && has_gateway && capture_resolv_conf) {
+		if (nm_ip4_config_capture_resolv_conf (priv->nameservers, NULL))
+			_NOTIFY (config, PROP_NAMESERVERS);
+	}
+
 	/* actually, nobody should be connected to the signal, just to be sure, notify */
 	_NOTIFY (config, PROP_ADDRESSES);
 	_NOTIFY (config, PROP_ROUTES);
-	if (gateway_changed)
+	if (priv->gateway != old_gateway)
 		_NOTIFY (config, PROP_GATEWAY);
 
 	return config;
diff --git a/src/nm-ip4-config.h b/src/nm-ip4-config.h
index 3b2b250c93..5b76fb4120 100644
--- a/src/nm-ip4-config.h
+++ b/src/nm-ip4-config.h
@@ -59,7 +59,7 @@ void nm_ip4_config_export (NMIP4Config *config);
 const char * nm_ip4_config_get_dbus_path (const NMIP4Config *config);
 
 /* Integration with nm-platform and nm-setting */
-NMIP4Config *nm_ip4_config_capture (int ifindex);
+NMIP4Config *nm_ip4_config_capture (int ifindex, gboolean capture_resolv_conf);
 gboolean nm_ip4_config_commit (const NMIP4Config *config, int ifindex, int priority);
 void nm_ip4_config_merge_setting (NMIP4Config *config, NMSettingIP4Config *setting);
 void nm_ip4_config_update_setting (const NMIP4Config *config, NMSettingIP4Config *setting);
@@ -144,4 +144,10 @@ guint32 nm_ip4_config_get_mtu (const NMIP4Config *config);
 void nm_ip4_config_hash (const NMIP4Config *config, GChecksum *sum, gboolean dns_only);
 gboolean nm_ip4_config_equal (const NMIP4Config *a, const NMIP4Config *b);
 
+/******************************************************/
+/* Testing-only functions */
+
+gboolean nm_ip4_config_capture_resolv_conf (GArray *nameservers,
+                                            const char *rc_contents);
+
 #endif /* NM_IP4_CONFIG_H */
diff --git a/src/nm-ip6-config.c b/src/nm-ip6-config.c
index 7522164b37..65cbd0be54 100644
--- a/src/nm-ip6-config.c
+++ b/src/nm-ip6-config.c
@@ -30,6 +30,7 @@
 #include "nm-dbus-manager.h"
 #include "nm-dbus-glib-types.h"
 #include "nm-ip6-config-glue.h"
+#include "NetworkManagerUtils.h"
 
 G_DEFINE_TYPE (NMIP6Config, nm_ip6_config, G_TYPE_OBJECT)
 
@@ -111,6 +112,54 @@ same_prefix (const struct in6_addr *address1, const struct in6_addr *address2, i
 
 /******************************************************************/
 
+/**
+ * nm_ip6_config_capture_resolv_conf():
+ * @nameservers: array of struct in6_addr
+ * @rc_contents: the contents of a resolv.conf or %NULL to read /etc/resolv.conf
+ *
+ * Reads all resolv.conf IPv6 nameservers and adds them to @nameservers.
+ *
+ * Returns: %TRUE if nameservers were added, %FALSE if @nameservers is unchanged
+ */
+gboolean
+nm_ip6_config_capture_resolv_conf (GArray *nameservers,
+                                   const char *rc_contents)
+{
+	GPtrArray *read_ns;
+	guint i, j;
+	gboolean changed = FALSE;
+
+	g_return_val_if_fail (nameservers != NULL, FALSE);
+
+	read_ns = nm_utils_read_resolv_conf_nameservers (rc_contents);
+	if (!read_ns)
+		return FALSE;
+
+	for (i = 0; i < read_ns->len; i++) {
+		const char *s = g_ptr_array_index (read_ns, i);
+		struct in6_addr ns = IN6ADDR_ANY_INIT;
+
+		if (!inet_pton (AF_INET6, s, (void *) &ns) || IN6_IS_ADDR_UNSPECIFIED (&ns))
+			continue;
+
+		/* Ignore duplicates */
+		for (j = 0; j < nameservers->len; j++) {
+			struct in6_addr *t = &g_array_index (nameservers, struct in6_addr, j);
+
+			if (IN6_ARE_ADDR_EQUAL (t, &ns))
+				break;
+		}
+
+		if (j == nameservers->len) {
+			g_array_append_val (nameservers, ns);
+			changed = TRUE;
+		}
+	}
+
+	g_ptr_array_unref (read_ns);
+	return changed;
+}
+
 static gboolean
 addresses_are_duplicate (const NMPlatformIP6Address *a, const NMPlatformIP6Address *b, gboolean consider_plen)
 {
@@ -125,12 +174,14 @@ routes_are_duplicate (const NMPlatformIP6Route *a, const NMPlatformIP6Route *b,
 }
 
 NMIP6Config *
-nm_ip6_config_capture (int ifindex)
+nm_ip6_config_capture (int ifindex, gboolean capture_resolv_conf)
 {
 	NMIP6Config *config;
 	NMIP6ConfigPrivate *priv;
 	guint i;
-	gboolean gateway_changed = FALSE;
+	guint lowest_metric = G_MAXUINT;
+	struct in6_addr old_gateway = IN6ADDR_ANY_INIT;
+	gboolean has_gateway = FALSE;
 
 	/* Slaves have no IP configuration */
 	if (nm_platform_link_get_master (ifindex) > 0)
@@ -146,24 +197,35 @@ nm_ip6_config_capture (int ifindex)
 	priv->routes = nm_platform_ip6_route_get_all (ifindex, TRUE);
 
 	/* Extract gateway from default route */
+	old_gateway = priv->gateway;
 	for (i = 0; i < priv->routes->len; i++) {
 		const NMPlatformIP6Route *route = &g_array_index (priv->routes, NMPlatformIP6Route, i);
 
 		if (IN6_IS_ADDR_UNSPECIFIED (&route->network)) {
-			if (!IN6_ARE_ADDR_EQUAL (&priv->gateway, &route->gateway)) {
+			if (route->metric < lowest_metric) {
 				priv->gateway = route->gateway;
-				gateway_changed = TRUE;
+				lowest_metric = route->metric;
+				has_gateway = TRUE;
 			}
+			has_gateway = TRUE;
 			/* Remove the default route from the list */
 			g_array_remove_index (priv->routes, i);
-			break;
+			i--;
 		}
 	}
 
+	/* If the interface has the default route, and has IPv4 addresses, capture
+	 * nameservers from /etc/resolv.conf.
+	 */
+	if (priv->addresses->len && has_gateway && capture_resolv_conf) {
+		if (nm_ip6_config_capture_resolv_conf (priv->nameservers, NULL))
+			_NOTIFY (config, PROP_NAMESERVERS);
+	}
+
 	/* actually, nobody should be connected to the signal, just to be sure, notify */
 	_NOTIFY (config, PROP_ADDRESSES);
 	_NOTIFY (config, PROP_ROUTES);
-	if (gateway_changed)
+	if (!IN6_ARE_ADDR_EQUAL (&priv->gateway, &old_gateway))
 		_NOTIFY (config, PROP_GATEWAY);
 
 	return config;
diff --git a/src/nm-ip6-config.h b/src/nm-ip6-config.h
index 538490a78c..aecdab2a81 100644
--- a/src/nm-ip6-config.h
+++ b/src/nm-ip6-config.h
@@ -58,7 +58,7 @@ void nm_ip6_config_export (NMIP6Config *config);
 const char * nm_ip6_config_get_dbus_path (const NMIP6Config *config);
 
 /* Integration with nm-platform and nm-setting */
-NMIP6Config *nm_ip6_config_capture (int ifindex);
+NMIP6Config *nm_ip6_config_capture (int ifindex, gboolean capture_resolv_conf);
 gboolean nm_ip6_config_commit (const NMIP6Config *config, int ifindex, int priority);
 void nm_ip6_config_merge_setting (NMIP6Config *config, NMSettingIP6Config *setting);
 void nm_ip6_config_update_setting (const NMIP6Config *config, NMSettingIP6Config *setting);
@@ -123,4 +123,10 @@ const struct in6_addr *nm_ip6_config_get_ptp_address (const NMIP6Config *config)
 void nm_ip6_config_hash (const NMIP6Config *config, GChecksum *sum, gboolean dns_only);
 gboolean nm_ip6_config_equal (const NMIP6Config *a, const NMIP6Config *b);
 
+/******************************************************/
+/* Testing-only functions */
+
+gboolean nm_ip6_config_capture_resolv_conf (GArray *nameservers,
+                                            const char *rc_contents);
+
 #endif /* NM_IP6_CONFIG_H */
diff --git a/src/nm-policy.c b/src/nm-policy.c
index fe21d40e51..677f8f9e9e 100644
--- a/src/nm-policy.c
+++ b/src/nm-policy.c
@@ -369,6 +369,8 @@ update_system_hostname (NMPolicy *policy, NMDevice *best4, NMDevice *best6)
 	NMPolicyPrivate *priv = NM_POLICY_GET_PRIVATE (policy);
 	char *configured_hostname = NULL;
 	const char *dhcp_hostname, *p;
+	NMIP4Config *ip4_config;
+	NMIP6Config *ip6_config;
 
 	g_return_if_fail (policy != NULL);
 
@@ -459,42 +461,37 @@ update_system_hostname (NMPolicy *policy, NMDevice *best4, NMDevice *best6)
 	/* No configured hostname, no automatically determined hostname, and no
 	 * bootup hostname. Start reverse DNS of the current IPv4 or IPv6 address.
 	 */
-	if (best4) {
-		NMIP4Config *ip4_config;
-		const NMPlatformIP4Address *addr4;
+	ip4_config = best4 ? nm_device_get_ip4_config (best4) : NULL;
+	ip6_config = best6 ? nm_device_get_ip6_config (best6) : NULL;
 
-		ip4_config = nm_device_get_ip4_config (best4);
-		if (   !ip4_config
-		    || (nm_ip4_config_get_num_nameservers (ip4_config) == 0)
-		    || (nm_ip4_config_get_num_addresses (ip4_config) == 0)) {
-			/* No valid IP4 config (!!); fall back to localhost.localdomain */
-			_set_hostname (policy, NULL, "no IPv4 config");
-			return;
-		}
+	if (   (!ip4_config || (nm_ip4_config_get_num_addresses (ip4_config) == 0))
+	    && (!ip6_config || (nm_ip6_config_get_num_addresses (ip6_config) == 0))) {
+		/* No valid IP config; fall back to localhost.localdomain */
+		_set_hostname (policy, NULL, "no IP config");
+		return;
+	}
+
+	if (ip4_config) {
+		const NMPlatformIP4Address *addr4;
 
 		addr4 = nm_ip4_config_get_address (ip4_config, 0);
 		g_assert (addr4); /* checked for > 1 address above */
 
 		priv->lookup_addr = g_inet_address_new_from_bytes ((guint8 *) &addr4->address,
 		                                                     G_SOCKET_FAMILY_IPV4);
-	} else {
-		NMIP6Config *ip6_config;
+	} else if (ip6_config) {
 		const NMPlatformIP6Address *addr6;
 
-		ip6_config = nm_device_get_ip6_config (best6);
-		if (   !ip6_config
-		    || (nm_ip6_config_get_num_nameservers (ip6_config) == 0)
-		    || (nm_ip6_config_get_num_addresses (ip6_config) == 0)) {
-			/* No valid IP6 config (!!); fall back to localhost.localdomain */
-			_set_hostname (policy, NULL, "no IPv6 config");
-			return;
-		}
-
 		addr6 = nm_ip6_config_get_address (ip6_config, 0);
 		g_assert (addr6); /* checked for > 1 address above */
 
 		priv->lookup_addr = g_inet_address_new_from_bytes ((guint8 *) &addr6->address,
 		                                                     G_SOCKET_FAMILY_IPV6);
+	} else {
+		/* Should never get here... */
+		g_warn_if_reached ();
+		_set_hostname (policy, NULL, "no IP config");
+		return;
 	}
 
 	priv->lookup_cancellable = g_cancellable_new ();
diff --git a/src/tests/Makefile.am b/src/tests/Makefile.am
index 9d17e9ad1a..eaa9d516fc 100644
--- a/src/tests/Makefile.am
+++ b/src/tests/Makefile.am
@@ -16,7 +16,8 @@ noinst_PROGRAMS = \
 	test-wifi-ap-utils \
 	test-ip4-config \
 	test-ip6-config \
-	test-dcb
+	test-dcb \
+	test-resolvconf-capture
 
 ####### DHCP options test #######
 
@@ -71,6 +72,14 @@ test_dcb_SOURCES = \
 test_dcb_LDADD = \
 	$(top_builddir)/src/libNetworkManager.la
 
+####### resolv.conf capture test #######
+
+test_resolvconf_capture_SOURCES = \
+	test-resolvconf-capture.c
+
+test_resolvconf_capture_LDADD = \
+	$(top_builddir)/src/libNetworkManager.la
+
 ####### secret agent interface test #######
 
 EXTRA_DIST = test-secret-agent.py
@@ -84,4 +93,5 @@ check-local: test-dhcp-options test-policy-hosts test-wifi-ap-utils test-ip4-con
 	$(abs_builddir)/test-ip4-config
 	$(abs_builddir)/test-ip6-config
 	$(abs_builddir)/test-dcb
+	$(abs_builddir)/test-resolvconf-capture
 
diff --git a/src/tests/test-resolvconf-capture.c b/src/tests/test-resolvconf-capture.c
new file mode 100644
index 0000000000..a04cbae8f2
--- /dev/null
+++ b/src/tests/test-resolvconf-capture.c
@@ -0,0 +1,226 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: t; c-basic-offset: 4 -*- */
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Copyright (C) 2013 Red Hat, Inc.
+ *
+ */
+
+#include <glib.h>
+#include <string.h>
+
+#include "NetworkManagerUtils.h"
+#include "nm-platform.h"
+
+static void
+test_capture_empty (void)
+{
+	GArray *ns4 = g_array_new (FALSE, FALSE, sizeof (guint32));
+	GArray *ns6 = g_array_new (FALSE, FALSE, sizeof (struct in6_addr));
+
+	g_assert (nm_ip4_config_capture_resolv_conf (ns4, "") == FALSE);
+	g_assert_cmpint (ns4->len, ==, 0);
+
+	g_assert (nm_ip6_config_capture_resolv_conf (ns6, "") == FALSE);
+	g_assert_cmpint (ns6->len, ==, 0);
+
+	g_array_free (ns4, TRUE);
+	g_array_free (ns6, TRUE);
+}
+
+static void
+assert_dns4_entry (const GArray *a, guint i, const char *s)
+{
+	guint32 n, m;
+
+	g_assert (inet_aton (s, (void *) &n) != 0);
+	m = g_array_index (a, guint32, i);
+	g_assert_cmpint (m, ==, n);
+}
+
+static void
+assert_dns6_entry (const GArray *a, guint i, const char *s)
+{
+	struct in6_addr n = IN6ADDR_ANY_INIT;
+	struct in6_addr *m;
+
+	g_assert (inet_pton (AF_INET6, s, (void *) &n) == 1);
+	m = &g_array_index (a, struct in6_addr, i);
+	g_assert (IN6_ARE_ADDR_EQUAL (&n, m));
+}
+
+static void
+test_capture_basic4 (void)
+{
+	GArray *ns4 = g_array_new (FALSE, FALSE, sizeof (guint32));
+	const char *rc =
+"# neato resolv.conf\r\n"
+"domain foobar.com\r\n"
+"search foobar.com\r\n"
+"nameserver 4.2.2.1\r\n"
+"nameserver 4.2.2.2\r\n";
+
+	g_assert (nm_ip4_config_capture_resolv_conf (ns4, rc));
+	g_assert_cmpint (ns4->len, ==, 2);
+	assert_dns4_entry (ns4, 0, "4.2.2.1");
+	assert_dns4_entry (ns4, 1, "4.2.2.2");
+
+	g_array_free (ns4, TRUE);
+}
+
+static void
+test_capture_dup4 (void)
+{
+	GArray *ns4 = g_array_new (FALSE, FALSE, sizeof (guint32));
+	const char *rc =
+"# neato resolv.conf\r\n"
+"domain foobar.com\r\n"
+"search foobar.com\r\n"
+"nameserver 4.2.2.1\r\n"
+"nameserver 4.2.2.1\r\n"
+"nameserver 4.2.2.2\r\n";
+
+	/* Check that duplicates are ignored */
+	g_assert (nm_ip4_config_capture_resolv_conf (ns4, rc));
+	g_assert_cmpint (ns4->len, ==, 2);
+	assert_dns4_entry (ns4, 0, "4.2.2.1");
+	assert_dns4_entry (ns4, 1, "4.2.2.2");
+
+	g_array_free (ns4, TRUE);
+}
+
+static void
+test_capture_basic6 (void)
+{
+	GArray *ns6 = g_array_new (FALSE, FALSE, sizeof (struct in6_addr));
+	const char *rc =
+"# neato resolv.conf\r\n"
+"domain foobar.com\r\n"
+"search foobar.com\r\n"
+"nameserver 2001:4860:4860::8888\r\n"
+"nameserver 2001:4860:4860::8844\r\n";
+
+	g_assert (nm_ip6_config_capture_resolv_conf (ns6, rc));
+	g_assert_cmpint (ns6->len, ==, 2);
+	assert_dns6_entry (ns6, 0, "2001:4860:4860::8888");
+	assert_dns6_entry (ns6, 1, "2001:4860:4860::8844");
+
+	g_array_free (ns6, TRUE);
+}
+
+static void
+test_capture_dup6 (void)
+{
+	GArray *ns6 = g_array_new (FALSE, FALSE, sizeof (struct in6_addr));
+	const char *rc =
+"# neato resolv.conf\r\n"
+"domain foobar.com\r\n"
+"search foobar.com\r\n"
+"nameserver 2001:4860:4860::8888\r\n"
+"nameserver 2001:4860:4860::8888\r\n"
+"nameserver 2001:4860:4860::8844\r\n";
+
+	/* Check that duplicates are ignored */
+	g_assert (nm_ip6_config_capture_resolv_conf (ns6, rc));
+	g_assert_cmpint (ns6->len, ==, 2);
+	assert_dns6_entry (ns6, 0, "2001:4860:4860::8888");
+	assert_dns6_entry (ns6, 1, "2001:4860:4860::8844");
+
+	g_array_free (ns6, TRUE);
+}
+
+static void
+test_capture_addr4_with_6 (void)
+{
+	GArray *ns4 = g_array_new (FALSE, FALSE, sizeof (guint32));
+	const char *rc =
+"# neato resolv.conf\r\n"
+"domain foobar.com\r\n"
+"search foobar.com\r\n"
+"nameserver 4.2.2.1\r\n"
+"nameserver 4.2.2.2\r\n"
+"nameserver 2001:4860:4860::8888\r\n";
+
+	g_assert (nm_ip4_config_capture_resolv_conf (ns4, rc));
+	g_assert_cmpint (ns4->len, ==, 2);
+	assert_dns4_entry (ns4, 0, "4.2.2.1");
+	assert_dns4_entry (ns4, 1, "4.2.2.2");
+
+	g_array_free (ns4, TRUE);
+}
+
+static void
+test_capture_addr6_with_4 (void)
+{
+	GArray *ns6 = g_array_new (FALSE, FALSE, sizeof (struct in6_addr));
+	const char *rc =
+"# neato resolv.conf\r\n"
+"domain foobar.com\r\n"
+"search foobar.com\r\n"
+"nameserver 4.2.2.1\r\n"
+"nameserver 2001:4860:4860::8888\r\n"
+"nameserver 2001:4860:4860::8844\r\n";
+
+	g_assert (nm_ip6_config_capture_resolv_conf (ns6, rc));
+	g_assert_cmpint (ns6->len, ==, 2);
+	assert_dns6_entry (ns6, 0, "2001:4860:4860::8888");
+	assert_dns6_entry (ns6, 1, "2001:4860:4860::8844");
+
+	g_array_free (ns6, TRUE);
+}
+
+static void
+test_capture_format (void)
+{
+	GArray *ns4 = g_array_new (FALSE, FALSE, sizeof (guint32));
+	const char *rc =
+" nameserver 4.2.2.1\r\n"     /* bad */
+"nameserver4.2.2.1\r\n"       /* bad */
+"nameserver     4.2.2.3\r"  /* good */
+"nameserver\t\t4.2.2.4\r\n"   /* good */
+"nameserver  4.2.2.5\t\t\r\n"; /* good */
+
+	g_assert (nm_ip4_config_capture_resolv_conf (ns4, rc));
+	g_assert_cmpint (ns4->len, ==, 3);
+	assert_dns4_entry (ns4, 0, "4.2.2.3");
+	assert_dns4_entry (ns4, 1, "4.2.2.4");
+	assert_dns4_entry (ns4, 2, "4.2.2.5");
+
+	g_array_free (ns4, TRUE);
+}
+
+/*******************************************/
+
+int
+main (int argc, char **argv)
+{
+	g_test_init (&argc, &argv, NULL);
+
+#if !GLIB_CHECK_VERSION (2,36,0)
+	g_type_init ();
+#endif
+
+	g_test_add_func ("/resolvconf-capture/empty", test_capture_empty);
+	g_test_add_func ("/resolvconf-capture/basic4", test_capture_basic4);
+	g_test_add_func ("/resolvconf-capture/dup4", test_capture_dup4);
+	g_test_add_func ("/resolvconf-capture/basic6", test_capture_basic6);
+	g_test_add_func ("/resolvconf-capture/dup6", test_capture_dup6);
+	g_test_add_func ("/resolvconf-capture/addr4-with-6", test_capture_addr4_with_6);
+	g_test_add_func ("/resolvconf-capture/addr6-with-4", test_capture_addr6_with_4);
+	g_test_add_func ("/resolvconf-capture/format", test_capture_format);
+
+	return g_test_run ();
+}
+