wifi: cfg80211: Add cluster joined notification APIs

The drivers should notify upper layers and user space when a NAN device
joins a cluster. This is needed, for example, to set the correct addr3
in SDF frames. Add API to report cluster join event.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20250908140015.ad27b7b6e4d9.I70b213a2a49f18d1ba2ad325e67e8eff51cc7a1f@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/cfg80211.h

@@ -10074,6 +10074,20 @@ void cfg80211_epcs_changed(struct net_device *netdev, bool enabled);
 void cfg80211_next_nan_dw_notif(struct wireless_dev *wdev,
 				struct ieee80211_channel *chan, gfp_t gfp);
 
+/**
+ * cfg80211_nan_cluster_joined - Notify about NAN cluster join
+ * @wdev: Pointer to the wireless device structure
+ * @cluster_id: Cluster ID of the NAN cluster that was joined or started
+ * @new_cluster: Indicates if this is a new cluster or an existing one
+ * @gfp: Memory allocation flags
+ *
+ * This function is used to notify user space when a NAN cluster has been
+ * joined, providing the cluster ID and a flag whether it is a new cluster.
+ */
+void cfg80211_nan_cluster_joined(struct wireless_dev *wdev,
+				 const u8 *cluster_id, bool new_cluster,
+				 gfp_t gfp);
+
 #ifdef CONFIG_CFG80211_DEBUGFS
 /**
  * wiphy_locked_debugfs_read - do a locked read in debugfs

include/uapi/linux/nl80211.h

@@ -1357,6 +1357,9 @@
  *	the device/driver shall take care of the actual transmission timing.
  *	This notification is only sent to the NAN interface owning socket
  *	(see %NL80211_ATTR_SOCKET_OWNER flag).
+ * @NL80211_CMD_NAN_CLUSTER_JOINED: This command is used to notify
+ *	user space that the NAN new cluster has been joined. The cluster ID is
+ *	indicated by %NL80211_ATTR_MAC.
  *
  * @NL80211_CMD_MAX: highest used command number
  * @__NL80211_CMD_AFTER_LAST: internal use
@@ -1619,6 +1622,7 @@ enum nl80211_commands {
 	NL80211_CMD_EPCS_CFG,
 
 	NL80211_CMD_NAN_NEXT_DW_NOTIFICATION,
+	NL80211_CMD_NAN_CLUSTER_JOINED,
 
 	/* add new commands above here */
 
@@ -2957,6 +2961,9 @@ enum nl80211_commands {
  *	%NL80211_CMD_START_NAN and %NL80211_CMD_CHANGE_NAN_CONFIG.
  *	See &enum nl80211_nan_conf_attributes for details.
  *	This attribute is optional.
+ * @NL80211_ATTR_NAN_NEW_CLUSTER: Flag attribute indicating that a new
+ *	NAN cluster has been created. This is used with
+ *	%NL80211_CMD_NAN_CLUSTER_JOINED
  *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
@@ -3521,6 +3528,7 @@ enum nl80211_attrs {
 	NL80211_ATTR_S1G_SHORT_BEACON,
 	NL80211_ATTR_BSS_PARAM,
 	NL80211_ATTR_NAN_CONFIG,
+	NL80211_ATTR_NAN_NEW_CLUSTER,
 
 	/* add attributes here, update the policy in nl80211.c */
 

net/wireless/nl80211.c

@@ -21809,6 +21809,47 @@ void cfg80211_next_nan_dw_notif(struct wireless_dev *wdev,
 }
 EXPORT_SYMBOL(cfg80211_next_nan_dw_notif);
 
+void cfg80211_nan_cluster_joined(struct wireless_dev *wdev,
+				 const u8 *cluster_id, bool new_cluster,
+				 gfp_t gfp)
+{
+	struct wiphy *wiphy = wdev->wiphy;
+	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
+	struct sk_buff *msg;
+	void *hdr;
+
+	trace_cfg80211_nan_cluster_joined(wdev, cluster_id, new_cluster);
+
+	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp);
+	if (!msg)
+		return;
+
+	hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_NAN_CLUSTER_JOINED);
+	if (!hdr)
+		goto nla_put_failure;
+
+	if (nla_put_u32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx) ||
+	    nla_put_u64_64bit(msg, NL80211_ATTR_WDEV, wdev_id(wdev),
+			      NL80211_ATTR_PAD) ||
+	    nla_put(msg, NL80211_ATTR_MAC, ETH_ALEN, cluster_id) ||
+	    (new_cluster && nla_put_flag(msg, NL80211_ATTR_NAN_NEW_CLUSTER)))
+		goto nla_put_failure;
+
+	genlmsg_end(msg, hdr);
+
+	if (!wdev->owner_nlportid)
+		genlmsg_multicast_netns(&nl80211_fam, wiphy_net(wiphy),
+					msg, 0, NL80211_MCGRP_NAN, gfp);
+	else
+		genlmsg_unicast(wiphy_net(wiphy), msg,
+				wdev->owner_nlportid);
+	return;
+
+ nla_put_failure:
+	nlmsg_free(msg);
+}
+EXPORT_SYMBOL(cfg80211_nan_cluster_joined);
+
 /* initialisation/exit functions */
 
 int __init nl80211_init(void)

net/wireless/trace.h

@@ -4182,6 +4182,25 @@ TRACE_EVENT(cfg80211_next_nan_dw_notif,
 		  WDEV_PR_ARG, CHAN_PR_ARG)
 );
 
+TRACE_EVENT(cfg80211_nan_cluster_joined,
+	TP_PROTO(struct wireless_dev *wdev,
+		 const u8 *cluster_id,
+		 bool new_cluster),
+	TP_ARGS(wdev, cluster_id, new_cluster),
+	TP_STRUCT__entry(
+		WDEV_ENTRY
+		MAC_ENTRY(cluster_id)
+		__field(bool, new_cluster)
+	),
+	TP_fast_assign(
+		WDEV_ASSIGN;
+		MAC_ASSIGN(cluster_id, cluster_id);
+		__entry->new_cluster = new_cluster;
+	),
+	TP_printk(WDEV_PR_FMT " cluster_id %pMF%s",
+		  WDEV_PR_ARG, __entry->cluster_id,
+		  __entry->new_cluster ? " [new]" : "")
+);
 #endif /* !__RDEV_OPS_TRACE || TRACE_HEADER_MULTI_READ */
 
 #undef TRACE_INCLUDE_PATH