core: fix auto-connect to hidden SSIDs (rh #707406)

Previously (in NM 0.8.x) most WiFi connection were from user settings service.
And the service updated 'seen-bssids' property when got connected.
But the settings service in 0.9 don't do that. That inhibits auto-connecting to
hidden networks. This commit takes care of updating 'seen-bssids'. However, we
don't want to write out the conection each time it's activated (touching /etc).
So, seen BSSIDs are kept separately from the connection in a look-aside file.

Signed-off-by: Jiří Klimeš <jklimes@redhat.com>

5 files changed, 256 insertions, 46 deletions

diff --git a/src/nm-device-wifi.c b/src/nm-device-wifi.c
index 7a6e7528b8..7f9b5d22ec 100644
--- a/src/nm-device-wifi.c
+++ b/src/nm-device-wifi.c
@@ -55,6 +55,7 @@
 #include "nm-setting-ip4-config.h"
 #include "nm-setting-ip6-config.h"
 #include "nm-system.h"
+#include "nm-settings-connection.h"
 
 static gboolean impl_device_get_access_points (NMDeviceWifi *device,
                                                GPtrArray **aps,
@@ -978,6 +979,28 @@ get_active_ap (NMDeviceWifi *self,
 }
 
 static void
+update_seen_bssids_cache (NMDeviceWifi *self, NMAccessPoint *ap)
+{
+	NMActRequest *req;
+	NMConnection *connection;
+
+	g_return_if_fail (ap != NULL);
+
+	/* Don't cache the BSSID for Ad-Hoc APs */
+	if (nm_ap_get_mode (ap) != NM_802_11_MODE_INFRA)
+		return;
+
+	if (nm_device_get_state (NM_DEVICE (self)) == NM_DEVICE_STATE_ACTIVATED) {
+		req = nm_device_get_act_request (NM_DEVICE (self));
+		if (req) {
+			connection = nm_act_request_get_connection (req);
+			nm_settings_connection_add_seen_bssid (NM_SETTINGS_CONNECTION (connection),
+			                                       nm_ap_get_address (ap));
+		}
+	}
+}
+
+static void
 set_current_ap (NMDeviceWifi *self, NMAccessPoint *new_ap)
 {
 	NMDeviceWifiPrivate *priv;
@@ -1003,6 +1026,9 @@ set_current_ap (NMDeviceWifi *self, NMAccessPoint *new_ap)
 		 */
 		priv->ap_list = g_slist_remove (priv->ap_list, new_ap);
 		priv->ap_list = g_slist_prepend (priv->ap_list, new_ap);
+
+		/* Update seen BSSIDs cache */
+		update_seen_bssids_cache (self, priv->current_ap);
 	}
 
 	/* Unref old AP here to ensure object lives if new_ap == old_ap */
@@ -3436,11 +3462,13 @@ activation_success_handler (NMDevice *dev)
 done:
 	periodic_update (self);
 
+	/* Update seen BSSIDs cache with the connected AP */
+	update_seen_bssids_cache (self, priv->current_ap);
+
 	/* Reset scan interval to something reasonable */
 	priv->scan_interval = SCAN_INTERVAL_MIN + (SCAN_INTERVAL_STEP * 2);
 }
 
-
 static void
 activation_failure_handler (NMDevice *dev)
 {
diff --git a/src/nm-manager.c b/src/nm-manager.c
index 5a3f7f7773..a15e4b7916 100644
--- a/src/nm-manager.c
+++ b/src/nm-manager.c
@@ -63,6 +63,7 @@
 #include "nm-settings-connection.h"
 #include "nm-manager-auth.h"
 #include "NetworkManagerUtils.h"
+#include "nm-utils.h"
 
 #define NM_AUTOIP_DBUS_SERVICE "org.freedesktop.nm_avahi_autoipd"
 #define NM_AUTOIP_DBUS_IFACE   "org.freedesktop.nm_avahi_autoipd"
@@ -1040,52 +1041,27 @@ manager_hidden_ap_found (NMDeviceInterface *device,
 {
 	NMManager *manager = NM_MANAGER (user_data);
 	NMManagerPrivate *priv = NM_MANAGER_GET_PRIVATE (manager);
-	const struct ether_addr *ap_addr;
-	const GByteArray *ap_ssid;
+	const struct ether_addr *bssid;
 	GSList *iter;
 	GSList *connections;
 	gboolean done = FALSE;
 
-	ap_ssid = nm_ap_get_ssid (ap);
-	if (ap_ssid && ap_ssid->len)
-		return;
+	g_return_if_fail (nm_ap_get_ssid (ap) == NULL);
 
-	ap_addr = nm_ap_get_address (ap);
-	g_assert (ap_addr);
+	bssid = nm_ap_get_address (ap);
+	g_assert (bssid);
 
 	/* Look for this AP's BSSID in the seen-bssids list of a connection,
 	 * and if a match is found, copy over the SSID */
 	connections = nm_settings_get_connections (priv->settings);
-
 	for (iter = connections; iter && !done; iter = g_slist_next (iter)) {
 		NMConnection *connection = NM_CONNECTION (iter->data);
-		NMSettingWireless *s_wireless;
-		const GByteArray *ssid;
-		guint32 num_bssids;
-		guint32 i;
-
-		s_wireless = (NMSettingWireless *) nm_connection_get_setting (connection, NM_TYPE_SETTING_WIRELESS);
-		if (!s_wireless)
-			continue;
-
-		num_bssids = nm_setting_wireless_get_num_seen_bssids (s_wireless);
-		if (num_bssids < 1)
-			continue;
-
-		ssid = nm_setting_wireless_get_ssid (s_wireless);
-		g_assert (ssid);
-
-		for (i = 0; i < num_bssids && !done; i++) {
-			const char *seen_bssid = nm_setting_wireless_get_seen_bssid (s_wireless, i);
-			struct ether_addr seen_addr;
+		NMSettingWireless *s_wifi;
 
-			if (ether_aton_r (seen_bssid, &seen_addr)) {
-				if (memcmp (ap_addr, &seen_addr, sizeof (struct ether_addr)) == 0) {
-					/* Copy the SSID from the connection to the AP */
-					nm_ap_set_ssid (ap, ssid);
-					done = TRUE;
-				}
-			}
+		s_wifi = nm_connection_get_setting_wireless (connection);
+		if (s_wifi) {
+			if (nm_settings_connection_has_seen_bssid (NM_SETTINGS_CONNECTION (connection), bssid))
+				nm_ap_set_ssid (ap, nm_setting_wireless_get_ssid (s_wifi));
 		}
 	}
 	g_slist_free (connections);
diff --git a/src/settings/nm-settings-connection.c b/src/settings/nm-settings-connection.c
index 828a036f76..c20ba8284a 100644
--- a/src/settings/nm-settings-connection.c
+++ b/src/settings/nm-settings-connection.c
@@ -22,6 +22,7 @@
 #include "config.h"
 
 #include <string.h>
+#include <netinet/ether.h>
 
 #include <NetworkManager.h>
 #include <dbus/dbus-glib-lowlevel.h>
@@ -38,8 +39,10 @@
 #include "nm-manager-auth.h"
 #include "nm-marshal.h"
 #include "nm-agent-manager.h"
+#include "NetworkManagerUtils.h"
 
 #define SETTINGS_TIMESTAMPS_FILE  LOCALSTATEDIR"/lib/NetworkManager/timestamps"
+#define SETTINGS_SEEN_BSSIDS_FILE LOCALSTATEDIR"/lib/NetworkManager/seen-bssids"
 
 static void impl_settings_connection_get_settings (NMSettingsConnection *connection,
                                                    DBusGMethodInvocation *context);
@@ -91,7 +94,8 @@ typedef struct {
 	NMSessionMonitor *session_monitor;
 	guint session_changed_id;
 
-	guint64 timestamp; /* Up-to-date timestamp of connection use */
+	guint64 timestamp;   /* Up-to-date timestamp of connection use */
+	GHashTable *seen_bssids; /* Up-to-date BSSIDs that's been seen for the connection */
 } NMSettingsConnectionPrivate;
 
 /**************************************************************/
@@ -455,12 +459,20 @@ commit_changes (NMSettingsConnection *connection,
 }
 
 static void
-remove_timestamp_from_db (NMSettingsConnection *connection)
+remove_entry_from_db (NMSettingsConnection *connection, const char* db_name)
 {
-	GKeyFile *timestamps_file;
+	GKeyFile *key_file;
+	const char *db_file;
 
-	timestamps_file = g_key_file_new ();
-	if (g_key_file_load_from_file (timestamps_file, SETTINGS_TIMESTAMPS_FILE, G_KEY_FILE_KEEP_COMMENTS, NULL)) {
+	if (strcmp (db_name, "timestamps") == 0)
+		db_file = SETTINGS_TIMESTAMPS_FILE;
+	else if (strcmp (db_name, "seen-bssids") == 0)
+		db_file = SETTINGS_SEEN_BSSIDS_FILE;
+	else
+		return;
+
+	key_file = g_key_file_new ();
+	if (g_key_file_load_from_file (key_file, db_file, G_KEY_FILE_KEEP_COMMENTS, NULL)) {
 		const char *connection_uuid;
 		char *data;
 		gsize len;
@@ -468,18 +480,18 @@ remove_timestamp_from_db (NMSettingsConnection *connection)
 
 		connection_uuid = nm_connection_get_uuid (NM_CONNECTION (connection));
 
-		g_key_file_remove_key (timestamps_file, "timestamps", connection_uuid, NULL);
-		data = g_key_file_to_data (timestamps_file, &len, &error);
+		g_key_file_remove_key (key_file, db_name, connection_uuid, NULL);
+		data = g_key_file_to_data (key_file, &len, &error);
 		if (data) {
-			g_file_set_contents (SETTINGS_TIMESTAMPS_FILE, data, len, &error);
+			g_file_set_contents (db_file, data, len, &error);
 			g_free (data);
 		}
 		if (error) {
-			nm_log_warn (LOGD_SETTINGS, "error writing timestamps file '%s': %s", SETTINGS_TIMESTAMPS_FILE, error->message);
+			nm_log_warn (LOGD_SETTINGS, "error writing %s file '%s': %s", db_name, db_file, error->message);
 			g_error_free (error);
 		}
 	}
-	g_key_file_free (timestamps_file);
+	g_key_file_free (key_file);
 }
 
 static void
@@ -499,7 +511,10 @@ do_delete (NMSettingsConnection *connection,
 	nm_agent_manager_delete_secrets (priv->agent_mgr, for_agents, FALSE, 0);
 
 	/* Remove timestamp from timestamps database file */
-	remove_timestamp_from_db (connection);
+	remove_entry_from_db (connection, "timestamps");
+
+	/* Remove connection from seen-bssids database file */
+	remove_entry_from_db (connection, "seen-bssids");
 
 	/* Signal the connection is removed and deleted */
 	g_signal_emit (connection, signals[REMOVED], 0);
@@ -1440,6 +1455,181 @@ nm_settings_connection_read_and_fill_timestamp (NMSettingsConnection *connection
 	g_key_file_free (timestamps_file);
 }
 
+static guint
+mac_hash (gconstpointer v)
+{
+	const guint8 *p = v;
+	guint32 i, h = 5381;
+
+	for (i = 0; i < ETH_ALEN; i++)
+		h = (h << 5) + h + p[i];
+	return h;
+}
+
+static gboolean
+mac_equal (gconstpointer a, gconstpointer b)
+{
+	return memcmp (a, b, ETH_ALEN) == 0;
+}
+
+static guint8 *
+mac_dup (const struct ether_addr *old)
+{
+	guint8 *new;
+
+	g_return_val_if_fail (old != NULL, NULL);
+
+	new = g_malloc0 (ETH_ALEN);
+	memcpy (new, old, ETH_ALEN);
+	return new;
+}
+
+/**
+ * nm_settings_connection_has_seen_bssid:
+ * @connection: the #NMSettingsConnection
+ * @bssid: the BSSID to check the seen BSSID list for
+ *
+ * Returns: TRUE if the given @bssid is in the seen BSSIDs list
+ **/
+gboolean
+nm_settings_connection_has_seen_bssid (NMSettingsConnection *connection,
+                                       const struct ether_addr *bssid)
+{
+	g_return_val_if_fail (connection != NULL, FALSE);
+	g_return_val_if_fail (NM_IS_SETTINGS_CONNECTION (connection), FALSE);
+	g_return_val_if_fail (bssid != NULL, FALSE);
+
+	return !!g_hash_table_lookup (NM_SETTINGS_CONNECTION_GET_PRIVATE (connection)->seen_bssids, bssid);
+}
+
+/**
+ * nm_settings_connection_add_seen_bssid:
+ * @connection: the #NMSettingsConnection
+ * @seen_bssid: BSSID to set into the connection and to store into
+ * the seen-bssids database
+ *
+ * Updates the connection and seen-bssids database with the provided BSSID.
+ **/
+void
+nm_settings_connection_add_seen_bssid (NMSettingsConnection *connection,
+                                       const struct ether_addr *seen_bssid)
+{
+	NMSettingsConnectionPrivate *priv = NM_SETTINGS_CONNECTION_GET_PRIVATE (connection);
+	const char *connection_uuid;
+	GKeyFile *seen_bssids_file;
+	char *data, *bssid_str;
+	const char **list;
+	gsize len;
+	GError *error = NULL;
+	GHashTableIter iter;
+	guint n;
+
+	g_return_if_fail (seen_bssid != NULL);
+
+	if (g_hash_table_lookup (priv->seen_bssids, seen_bssid))
+		return;  /* Already in the list */
+
+	/* Add the new BSSID; let the hash take ownership of the allocated BSSID string */
+	bssid_str = nm_ether_ntop (seen_bssid);
+	g_return_if_fail (bssid_str != NULL);
+	g_hash_table_insert (priv->seen_bssids, mac_dup (seen_bssid), bssid_str);
+
+	/* Build up a list of all the BSSIDs in string form */
+	n = 0;
+	list = g_malloc0 (g_hash_table_size (priv->seen_bssids) * sizeof (char *));
+	g_hash_table_iter_init (&iter, priv->seen_bssids);
+	while (g_hash_table_iter_next (&iter, NULL, (gpointer) &bssid_str))
+		list[n++] = bssid_str;
+
+	/* Save BSSID to seen-bssids file */
+	seen_bssids_file = g_key_file_new ();
+	g_key_file_set_list_separator (seen_bssids_file, ',');
+	if (!g_key_file_load_from_file (seen_bssids_file, SETTINGS_SEEN_BSSIDS_FILE, G_KEY_FILE_KEEP_COMMENTS, &error)) {
+		if (!g_error_matches (error, G_FILE_ERROR, G_FILE_ERROR_NOENT)) {
+			nm_log_warn (LOGD_SETTINGS, "error parsing seen-bssids file '%s': %s",
+			             SETTINGS_SEEN_BSSIDS_FILE, error->message);
+		}
+		g_clear_error (&error);
+	}
+
+	connection_uuid = nm_connection_get_uuid (NM_CONNECTION (connection));
+	g_key_file_set_string_list (seen_bssids_file, "seen-bssids", connection_uuid, list, n);
+	g_free (list);
+
+	data = g_key_file_to_data (seen_bssids_file, &len, &error);
+	if (data) {
+		g_file_set_contents (SETTINGS_SEEN_BSSIDS_FILE, data, len, &error);
+		g_free (data);
+	}
+	g_key_file_free (seen_bssids_file);
+
+	if (error) {
+		nm_log_warn (LOGD_SETTINGS, "error saving seen-bssids to file '%s': %s",
+		             SETTINGS_SEEN_BSSIDS_FILE, error->message);
+		g_error_free (error);
+	}
+}
+
+static void
+add_seen_bssid_string (NMSettingsConnection *self, const char *bssid)
+{
+	struct ether_addr mac;
+
+	g_return_if_fail (bssid != NULL);
+	if (ether_aton_r (bssid, &mac)) {
+		g_hash_table_insert (NM_SETTINGS_CONNECTION_GET_PRIVATE (self)->seen_bssids,
+		                     mac_dup (&mac),
+		                     g_strdup (bssid));
+	}
+}
+
+/**
+ * nm_settings_connection_read_and_fill_seen_bssids:
+ * @connection: the #NMSettingsConnection
+ *
+ * Retrieves seen BSSIDs of the connection from database file and stores then into the
+ * connection private data.
+ **/
+void
+nm_settings_connection_read_and_fill_seen_bssids (NMSettingsConnection *connection)
+{
+	NMSettingsConnectionPrivate *priv = NM_SETTINGS_CONNECTION_GET_PRIVATE (connection);
+	const char *connection_uuid;
+	GKeyFile *seen_bssids_file;
+	char **tmp_strv = NULL;
+	gsize i, len = 0;
+	NMSettingWireless *s_wifi;
+
+	/* Get seen BSSIDs from database file */
+	seen_bssids_file = g_key_file_new ();
+	g_key_file_set_list_separator (seen_bssids_file, ',');
+	if (g_key_file_load_from_file (seen_bssids_file, SETTINGS_SEEN_BSSIDS_FILE, G_KEY_FILE_KEEP_COMMENTS, NULL)) {
+		connection_uuid = nm_connection_get_uuid (NM_CONNECTION (connection));
+		tmp_strv = g_key_file_get_string_list (seen_bssids_file, "seen-bssids", connection_uuid, &len, NULL);
+	}
+	g_key_file_free (seen_bssids_file);
+
+	/* Update connection's seen-bssids */
+	if (tmp_strv) {
+		g_hash_table_remove_all (priv->seen_bssids);
+		for (i = 0; i < len; i++)
+			add_seen_bssid_string (connection, tmp_strv[i]);
+		g_strfreev (tmp_strv);
+	} else {
+		/* If this connection didn't have an entry in the seen-bssids database,
+		 * maybe this is the first time we've read it in, so populate the
+		 * seen-bssids list from the deprecated seen-bssids property of the
+		 * wifi setting.
+		 */
+		s_wifi = nm_connection_get_setting_wireless (NM_CONNECTION (connection));
+		if (s_wifi) {
+			len = nm_setting_wireless_get_num_seen_bssids (s_wifi);
+			for (i = 0; i < len; i++)
+				add_seen_bssid_string (connection, nm_setting_wireless_get_seen_bssid (s_wifi, i));
+		}
+	}
+}
+
 /**************************************************************/
 
 static void
@@ -1463,6 +1653,8 @@ nm_settings_connection_init (NMSettingsConnection *self)
 	                                             self);
 
 	priv->agent_mgr = nm_agent_manager_get ();
+
+	priv->seen_bssids = g_hash_table_new_full (mac_hash, mac_equal, g_free, g_free);
 }
 
 static void
@@ -1490,6 +1682,8 @@ dispose (GObject *object)
 		nm_agent_manager_cancel_secrets (priv->agent_mgr, GPOINTER_TO_UINT (iter->data));
 	g_slist_free (priv->reqs);
 
+	g_hash_table_destroy (priv->seen_bssids);
+
 	set_visible (self, FALSE);
 
 	if (priv->session_changed_id)
diff --git a/src/settings/nm-settings-connection.h b/src/settings/nm-settings-connection.h
index 116bfdcc94..af90c5144d 100644
--- a/src/settings/nm-settings-connection.h
+++ b/src/settings/nm-settings-connection.h
@@ -24,6 +24,7 @@
 
 #include <nm-connection.h>
 #include "nm-settings-flags.h"
+#include <net/ethernet.h>
 
 G_BEGIN_DECLS
 
@@ -124,6 +125,14 @@ void nm_settings_connection_update_timestamp (NMSettingsConnection *connection,
 
 void nm_settings_connection_read_and_fill_timestamp (NMSettingsConnection *connection);
 
+gboolean nm_settings_connection_has_seen_bssid (NMSettingsConnection *connection,
+                                                const struct ether_addr *bssid);
+
+void nm_settings_connection_add_seen_bssid (NMSettingsConnection *connection,
+                                            const struct ether_addr *seen_bssid);
+
+void nm_settings_connection_read_and_fill_seen_bssids (NMSettingsConnection *connection);
+
 G_END_DECLS
 
 #endif /* NM_SETTINGS_CONNECTION_H */
diff --git a/src/settings/nm-settings.c b/src/settings/nm-settings.c
index e23e8d1336..83297809d0 100644
--- a/src/settings/nm-settings.c
+++ b/src/settings/nm-settings.c
@@ -773,6 +773,9 @@ claim_connection (NMSettings *self,
 	/* Read timestamp from look-aside file and put it into the connection's data */
 	nm_settings_connection_read_and_fill_timestamp (connection);
 
+	/* Read seen-bssids from look-aside file and put it into the connection's data */
+	nm_settings_connection_read_and_fill_seen_bssids (connection);
+
 	/* Ensure it's initial visibility is up-to-date */
 	nm_settings_connection_recheck_visibility (connection);