From a2354f88a6798a86676a6d62549dc86a44142b3f Mon Sep 17 00:00:00 2001
From: James Prestwood <james.prestwood@linux.intel.com>
Date: Fri, 25 Jan 2019 11:23:12 -0800
Subject: [PATCH] station/netdev: handle rekeying based on driver features

A new driver extended feature bit was added signifying if the driver
supports PTK replacement/rekeying. During a connect, netdev checks
for the driver feature and sets the handshakes 'no_rekey' flag
accordingly.

At some point the AP will decide to rekey which is handled inside
eapol. If no_rekey is unset we rekey as normal and the connection
remains open. If we have set no_rekey eapol will emit
HANDSHAKE_EVENT_REKEY_FAILED, which is now caught inside station. If
this happens our only choice is to fully disconnect and reconnect.
---
 src/netdev.c  |  4 ++++
 src/station.c | 43 ++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/src/netdev.c b/src/netdev.c
index e2998284..082bcbbf 100644
--- a/src/netdev.c
+++ b/src/netdev.c
@@ -2748,6 +2748,10 @@ static int netdev_connect_common(struct netdev *netdev,
 	handshake_state_set_authenticator_address(hs, bss->addr);
 	handshake_state_set_supplicant_address(hs, netdev->addr);
 
+	if (!wiphy_has_ext_feature(netdev->wiphy,
+					NL80211_EXT_FEATURE_CAN_REPLACE_PTK0))
+		handshake_state_set_no_rekey(hs, true);
+
 	if (netdev->sae_sm)
 		sae_start(netdev->sae_sm);
 	else if (netdev->owe)
diff --git a/src/station.c b/src/station.c
index 2778b8e9..2a2e0921 100644
--- a/src/station.c
+++ b/src/station.c
@@ -377,6 +377,8 @@ void station_set_scan_results(struct station *station, struct l_queue *bss_list,
 	l_queue_destroy(old_bss_list, bss_free);
 }
 
+static void station_reconnect(struct station *station);
+
 static void station_handshake_event(struct handshake_state *hs,
 					enum handshake_event event,
 					void *event_data, void *user_data)
@@ -397,8 +399,11 @@ static void station_handshake_event(struct handshake_state *hs,
 	case HANDSHAKE_EVENT_FAILED:
 		netdev_handshake_failed(hs, l_get_u16(event_data));
 		break;
-	case HANDSHAKE_EVENT_SETTING_KEYS_FAILED:
+	case HANDSHAKE_EVENT_REKEY_FAILED:
+		station_reconnect(station);
+		break;
 	case HANDSHAKE_EVENT_COMPLETE:
+	case HANDSHAKE_EVENT_SETTING_KEYS_FAILED:
 		/*
 		 * currently we dont care about any other events. The
 		 * netdev_connect_cb will notify us when the connection is
@@ -1811,6 +1816,42 @@ static struct l_dbus_message *station_dbus_connect_hidden_network(
 	return NULL;
 }
 
+static void station_disconnect_reconnect_cb(struct netdev *netdev, bool success,
+					void *user_data)
+{
+	struct station *station = user_data;
+	struct handshake_state *hs;
+	int r;
+
+	hs = station_handshake_setup(station, station->connected_network,
+					station->connected_bss);
+	if (!hs)
+		goto error;
+
+	r = netdev_connect(station->netdev, station->connected_bss, hs,
+				station_netdev_event, station_connect_cb,
+				station);
+	if (r < 0)
+		goto error;
+
+	return;
+
+error:
+	station_disconnect(station);
+}
+
+static void station_reconnect(struct station *station)
+{
+	/*
+	 * Rather than doing 4 or so state changes, lets just go into
+	 * roaming for the duration of this reconnect.
+	 */
+	station_enter_state(station, STATION_STATE_ROAMING);
+
+	netdev_disconnect(station->netdev, station_disconnect_reconnect_cb,
+				station);
+}
+
 static void station_disconnect_cb(struct netdev *netdev, bool success,
 					void *user_data)
 {