wifi: cfg80211: do some rework towards MLO link APIs

In order to support multi-link operation with multiple links,
start adding some APIs. The notable addition here is to have
the link ID in a new nl80211 attribute, that will be used to
differentiate the links in many nl80211 operations.

So far, this patch adds the netlink NL80211_ATTR_MLO_LINK_ID
attribute (as well as the NL80211_ATTR_MLO_LINKS attribute)
and plugs it through the system in some places, checking the
validity etc. along with other infrastructure needed for it.

For now, I've decided to include only the over-the-air link
ID in the API. I know we discussed that we eventually need to
have to have other ways of identifying a link, but for local
AP mode and auth/assoc commands as well as set_key etc. we'll
use the OTA ID.

Also included in this patch is some refactoring of the data
structures in struct wireless_dev, splitting for the first
time the data into type dependent pieces, to make reasoning
about these things easier.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 54 insertions, 48 deletions

diff --git a/net/wireless/sme.c b/net/wireless/sme.c
index ff4d48fcbfb2..35602201057b 100644
--- a/net/wireless/sme.c
+++ b/net/wireless/sme.c
@@ -5,7 +5,7 @@
  * (for nl80211's connect() and wext)
  *
  * Copyright 2009	Johannes Berg <johannes@sipsolutions.net>
- * Copyright (C) 2009, 2020 Intel Corporation. All rights reserved.
+ * Copyright (C) 2009, 2020, 2022 Intel Corporation. All rights reserved.
  * Copyright 2017	Intel Deutschland GmbH
  */
 
@@ -454,6 +454,20 @@ void cfg80211_sme_abandon_assoc(struct wireless_dev *wdev)
 	schedule_work(&rdev->conn_work);
 }
 
+static void cfg80211_wdev_release_bsses(struct wireless_dev *wdev)
+{
+	unsigned int link;
+
+	for_each_valid_link(wdev, link) {
+		if (!wdev->links[link].client.current_bss)
+			continue;
+		cfg80211_unhold_bss(wdev->links[link].client.current_bss);
+		cfg80211_put_bss(wdev->wiphy,
+				 &wdev->links[link].client.current_bss->pub);
+		wdev->links[link].client.current_bss = NULL;
+	}
+}
+
 static int cfg80211_sme_get_conn_ies(struct wireless_dev *wdev,
 				     const u8 *ies, size_t ies_len,
 				     const u8 **out_ies, size_t *out_ies_len)
@@ -521,12 +535,11 @@ static int cfg80211_sme_connect(struct wireless_dev *wdev,
 	if (!rdev->ops->auth || !rdev->ops->assoc)
 		return -EOPNOTSUPP;
 
-	if (wdev->current_bss) {
-		cfg80211_unhold_bss(wdev->current_bss);
-		cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
-		wdev->current_bss = NULL;
+	cfg80211_wdev_release_bsses(wdev);
 
+	if (wdev->connected) {
 		cfg80211_sme_free(wdev);
+		wdev->connected = false;
 	}
 
 	if (wdev->conn)
@@ -563,8 +576,8 @@ static int cfg80211_sme_connect(struct wireless_dev *wdev,
 		wdev->conn->auto_auth = false;
 	}
 
-	wdev->conn->params.ssid = wdev->ssid;
-	wdev->conn->params.ssid_len = wdev->ssid_len;
+	wdev->conn->params.ssid = wdev->u.client.ssid;
+	wdev->conn->params.ssid_len = wdev->u.client.ssid_len;
 
 	/* see if we have the bss already */
 	bss = cfg80211_get_conn_bss(wdev);
@@ -648,7 +661,7 @@ static bool cfg80211_is_all_idle(void)
 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
 		list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list) {
 			wdev_lock(wdev);
-			if (wdev->conn || wdev->current_bss ||
+			if (wdev->conn || wdev->connected ||
 			    cfg80211_beaconing_iface_active(wdev))
 				is_all_idle = false;
 			wdev_unlock(wdev);
@@ -668,7 +681,6 @@ static void disconnect_work(struct work_struct *work)
 
 DECLARE_WORK(cfg80211_disconnect_work, disconnect_work);
 
-
 /*
  * API calls for drivers implementing connect/disconnect and
  * SME event handling
@@ -729,23 +741,19 @@ void __cfg80211_connect_result(struct net_device *dev,
 	if (!cr->bss && (cr->status == WLAN_STATUS_SUCCESS)) {
 		WARN_ON_ONCE(!wiphy_to_rdev(wdev->wiphy)->ops->connect);
 		cr->bss = cfg80211_get_bss(wdev->wiphy, NULL, cr->bssid,
-					   wdev->ssid, wdev->ssid_len,
+					   wdev->u.client.ssid, wdev->u.client.ssid_len,
 					   wdev->conn_bss_type,
 					   IEEE80211_PRIVACY_ANY);
 		if (cr->bss)
 			cfg80211_hold_bss(bss_from_pub(cr->bss));
 	}
 
-	if (wdev->current_bss) {
-		cfg80211_unhold_bss(wdev->current_bss);
-		cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
-		wdev->current_bss = NULL;
-	}
+	cfg80211_wdev_release_bsses(wdev);
 
 	if (cr->status != WLAN_STATUS_SUCCESS) {
 		kfree_sensitive(wdev->connect_keys);
 		wdev->connect_keys = NULL;
-		wdev->ssid_len = 0;
+		wdev->u.client.ssid_len = 0;
 		wdev->conn_owner_nlportid = 0;
 		if (cr->bss) {
 			cfg80211_unhold_bss(bss_from_pub(cr->bss));
@@ -758,7 +766,9 @@ void __cfg80211_connect_result(struct net_device *dev,
 	if (WARN_ON(!cr->bss))
 		return;
 
-	wdev->current_bss = bss_from_pub(cr->bss);
+	wdev->links[0].client.current_bss = bss_from_pub(cr->bss);
+	wdev->connected = true;
+	ether_addr_copy(wdev->u.client.connected_addr, cr->bss->bssid);
 
 	if (!(wdev->wiphy->flags & WIPHY_FLAG_HAS_STATIC_WEP))
 		cfg80211_upload_connect_keys(wdev);
@@ -801,7 +811,7 @@ void cfg80211_connect_done(struct net_device *dev,
 
 			found = cfg80211_get_bss(wdev->wiphy, NULL,
 						 params->bss->bssid,
-						 wdev->ssid, wdev->ssid_len,
+						 wdev->u.client.ssid, wdev->u.client.ssid_len,
 						 wdev->conn_bss_type,
 						 IEEE80211_PRIVACY_ANY);
 			if (found) {
@@ -906,18 +916,17 @@ void __cfg80211_roamed(struct wireless_dev *wdev,
 		    wdev->iftype != NL80211_IFTYPE_P2P_CLIENT))
 		goto out;
 
-	if (WARN_ON(!wdev->current_bss))
+	if (WARN_ON(!wdev->connected))
 		goto out;
 
-	cfg80211_unhold_bss(wdev->current_bss);
-	cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
-	wdev->current_bss = NULL;
+	cfg80211_wdev_release_bsses(wdev);
 
 	if (WARN_ON(!info->bss))
 		return;
 
 	cfg80211_hold_bss(bss_from_pub(info->bss));
-	wdev->current_bss = bss_from_pub(info->bss);
+	wdev->links[0].client.current_bss = bss_from_pub(info->bss);
+	ether_addr_copy(wdev->u.client.connected_addr, info->bss->bssid);
 
 	wdev->unprot_beacon_reported = 0;
 	nl80211_send_roamed(wiphy_to_rdev(wdev->wiphy),
@@ -963,8 +972,8 @@ void cfg80211_roamed(struct net_device *dev, struct cfg80211_roam_info *info,
 
 	if (!info->bss) {
 		info->bss = cfg80211_get_bss(wdev->wiphy, info->channel,
-					     info->bssid, wdev->ssid,
-					     wdev->ssid_len,
+					     info->bssid, wdev->u.client.ssid,
+					     wdev->u.client.ssid_len,
 					     wdev->conn_bss_type,
 					     IEEE80211_PRIVACY_ANY);
 	}
@@ -1034,8 +1043,8 @@ void __cfg80211_port_authorized(struct wireless_dev *wdev, const u8 *bssid)
 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
 		return;
 
-	if (WARN_ON(!wdev->current_bss) ||
-	    WARN_ON(!ether_addr_equal(wdev->current_bss->pub.bssid, bssid)))
+	if (WARN_ON(!wdev->connected) ||
+	    WARN_ON(!ether_addr_equal(wdev->u.client.connected_addr, bssid)))
 		return;
 
 	nl80211_send_port_authorized(wiphy_to_rdev(wdev->wiphy), wdev->netdev,
@@ -1087,13 +1096,9 @@ void __cfg80211_disconnected(struct net_device *dev, const u8 *ie,
 		    wdev->iftype != NL80211_IFTYPE_P2P_CLIENT))
 		return;
 
-	if (wdev->current_bss) {
-		cfg80211_unhold_bss(wdev->current_bss);
-		cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
-	}
-
-	wdev->current_bss = NULL;
-	wdev->ssid_len = 0;
+	cfg80211_wdev_release_bsses(wdev);
+	wdev->connected = false;
+	wdev->u.client.ssid_len = 0;
 	wdev->conn_owner_nlportid = 0;
 	kfree_sensitive(wdev->connect_keys);
 	wdev->connect_keys = NULL;
@@ -1182,19 +1187,20 @@ int cfg80211_connect(struct cfg80211_registered_device *rdev,
 	 * already connected, so reject a new SSID unless it's the
 	 * same (which is the case for re-association.)
 	 */
-	if (wdev->ssid_len &&
-	    (wdev->ssid_len != connect->ssid_len ||
-	     memcmp(wdev->ssid, connect->ssid, wdev->ssid_len)))
+	if (wdev->u.client.ssid_len &&
+	    (wdev->u.client.ssid_len != connect->ssid_len ||
+	     memcmp(wdev->u.client.ssid, connect->ssid, wdev->u.client.ssid_len)))
 		return -EALREADY;
 
 	/*
 	 * If connected, reject (re-)association unless prev_bssid
 	 * matches the current BSSID.
 	 */
-	if (wdev->current_bss) {
+	if (wdev->connected) {
 		if (!prev_bssid)
 			return -EALREADY;
-		if (!ether_addr_equal(prev_bssid, wdev->current_bss->pub.bssid))
+		if (!ether_addr_equal(prev_bssid,
+				      wdev->u.client.connected_addr))
 			return -ENOTCONN;
 	}
 
@@ -1245,8 +1251,8 @@ int cfg80211_connect(struct cfg80211_registered_device *rdev,
 	}
 
 	wdev->connect_keys = connkeys;
-	memcpy(wdev->ssid, connect->ssid, connect->ssid_len);
-	wdev->ssid_len = connect->ssid_len;
+	memcpy(wdev->u.client.ssid, connect->ssid, connect->ssid_len);
+	wdev->u.client.ssid_len = connect->ssid_len;
 
 	wdev->conn_bss_type = connect->pbss ? IEEE80211_BSS_TYPE_PBSS :
 					      IEEE80211_BSS_TYPE_ESS;
@@ -1262,8 +1268,8 @@ int cfg80211_connect(struct cfg80211_registered_device *rdev,
 		 * This could be reassoc getting refused, don't clear
 		 * ssid_len in that case.
 		 */
-		if (!wdev->current_bss)
-			wdev->ssid_len = 0;
+		if (!wdev->connected)
+			wdev->u.client.ssid_len = 0;
 		return err;
 	}
 
@@ -1287,7 +1293,7 @@ int cfg80211_disconnect(struct cfg80211_registered_device *rdev,
 		err = cfg80211_sme_disconnect(wdev, reason);
 	else if (!rdev->ops->disconnect)
 		cfg80211_mlme_down(rdev, dev);
-	else if (wdev->ssid_len)
+	else if (wdev->u.client.ssid_len)
 		err = rdev_disconnect(rdev, dev, reason);
 
 	/*
@@ -1295,8 +1301,8 @@ int cfg80211_disconnect(struct cfg80211_registered_device *rdev,
 	 * in which case cfg80211_disconnected() will take care of
 	 * this later.
 	 */
-	if (!wdev->current_bss)
-		wdev->ssid_len = 0;
+	if (!wdev->connected)
+		wdev->u.client.ssid_len = 0;
 
 	return err;
 }
@@ -1320,7 +1326,7 @@ void cfg80211_autodisconnect_wk(struct work_struct *work)
 			break;
 		case NL80211_IFTYPE_AP:
 		case NL80211_IFTYPE_P2P_GO:
-			__cfg80211_stop_ap(rdev, wdev->netdev, false);
+			__cfg80211_stop_ap(rdev, wdev->netdev, -1, false);
 			break;
 		case NL80211_IFTYPE_MESH_POINT:
 			__cfg80211_leave_mesh(rdev, wdev->netdev);
@@ -1332,7 +1338,7 @@ void cfg80211_autodisconnect_wk(struct work_struct *work)
 			 * ops->disconnect not implemented.  Otherwise we can
 			 * use cfg80211_disconnect.
 			 */
-			if (rdev->ops->disconnect || wdev->current_bss)
+			if (rdev->ops->disconnect || wdev->connected)
 				cfg80211_disconnect(rdev, wdev->netdev,
 						    WLAN_REASON_DEAUTH_LEAVING,
 						    true);