[PATCH v3 2/2] mac80211: Add FILS discovery support

[Aloka Dixit <alokad@codeaurora.org>]

This patch adds mac80211 support to configure FILS discovery
transmission.
Changes include functions to store and retrieve FILS discovery
template, minimum and maximum packet intervals, beacon response
window and option to omit replicated probe responses.

Signed-off-by: Aloka Dixit <alokad@codeaurora.org>
---
v3: Only FILS discovery related implementation

v2: FILS discovery and bcast probe resp support

 include/net/mac80211.h     | 31 +++++++++++++++++++++++++
 net/mac80211/cfg.c         | 46 ++++++++++++++++++++++++++++++++++++++
 net/mac80211/ieee80211_i.h |  7 ++++++
 net/mac80211/tx.c          | 25 +++++++++++++++++++++
 4 files changed, 109 insertions(+)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 11d5610d2ad5..19daa61ed22d 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -317,6 +317,7 @@ struct ieee80211_vif_chanctx_switch {
  * @BSS_CHANGED_TWT: TWT status changed
  * @BSS_CHANGED_HE_OBSS_PD: OBSS Packet Detection status changed.
  * @BSS_CHANGED_HE_BSS_COLOR: BSS Color has changed
+ * @BSS_CHANGED_FILS_DISCOVERY: FILS discovery status changed.
  *
  */
 enum ieee80211_bss_change {
@@ -350,6 +351,7 @@ enum ieee80211_bss_change {
 	BSS_CHANGED_TWT			= 1<<27,
 	BSS_CHANGED_HE_OBSS_PD		= 1<<28,
 	BSS_CHANGED_HE_BSS_COLOR	= 1<<29,
+	BSS_CHANGED_FILS_DISCOVERY      = 1<<30,
 
 	/* when adding here, make sure to change ieee80211_reconfig */
 };
@@ -490,6 +492,22 @@ struct ieee80211_ftm_responder_params {
 	size_t civicloc_len;
 };
 
+/**
+ * struct ieee80211_fils_discovery - FILS discovery parameters from
+ * IEEE Std 802.11ai-2016, Annex C.3 MIB detail.
+ *
+ * @min_interval: Minimum packet interval in TUs (0 - 10000)
+ * @max_interval: Maximum packet interval in TUs (0 - 10000)
+ * @bcn_resp_win: Beacon response window in unit of 0.1 msec (0 - 1000000)
+ * @omit_replicate_probe_resp: Omit replicate_probe_response
+ */
+struct ieee80211_fils_discovery {
+	u32 min_interval;
+	u32 max_interval;
+	u32 bcn_resp_win;
+	bool omit_replicate_probe_resp;
+};
+
 /**
  * struct ieee80211_bss_conf - holds the BSS's changing parameters
  *
@@ -607,6 +625,7 @@ struct ieee80211_ftm_responder_params {
  * @he_oper: HE operation information of the AP we are connected to
  * @he_obss_pd: OBSS Packet Detection parameters.
  * @he_bss_color: BSS coloring settings, if BSS supports HE
+ * @fils_discovery: FILS discovery configuration
  */
 struct ieee80211_bss_conf {
 	const u8 *bssid;
@@ -674,6 +693,7 @@ struct ieee80211_bss_conf {
 	} he_oper;
 	struct ieee80211_he_obss_pd he_obss_pd;
 	struct cfg80211_he_bss_color he_bss_color;
+	struct ieee80211_fils_discovery fils_discovery;
 };
 
 /**
@@ -6558,4 +6578,15 @@ u32 ieee80211_calc_tx_airtime(struct ieee80211_hw *hw,
  */
 bool ieee80211_set_hw_80211_encap(struct ieee80211_vif *vif, bool enable);
 
+/**
+ * ieee80211_get_fils_discovery_tmpl - Get FILS discovery template.
+ * @hw: pointer obtained from ieee80211_alloc_hw().
+ * @vif: &struct ieee80211_vif pointer from the add_interface callback.
+ *
+ * The driver is responsible for freeing the returned skb.
+ *
+ * Return: FILS discovery template. %NULL on error.
+ */
+struct sk_buff *ieee80211_get_fils_discovery_tmpl(struct ieee80211_hw *hw,
+						  struct ieee80211_vif *vif);
 #endif /* MAC80211_H */
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 9b360544ad6f..664602f145cf 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -837,6 +837,35 @@ static int ieee80211_set_probe_resp(struct ieee80211_sub_if_data *sdata,
 	return 0;
 }
 
+static int ieee80211_set_fils_discovery(struct ieee80211_sub_if_data *sdata,
+					struct cfg80211_fils_discovery *params)
+{
+	struct fils_discovery_data *new, *old = NULL;
+	struct ieee80211_fils_discovery *fd;
+
+	fd = &sdata->vif.bss_conf.fils_discovery;
+	fd->min_interval = params->min_interval;
+	fd->max_interval = params->max_interval;
+	fd->bcn_resp_win = params->bcn_resp_win;
+	fd->omit_replicate_probe_resp = params->omit_replicate_probe_resp;
+
+	if (!params->tmpl || !params->tmpl_len) /* Optional template */
+		return 0;
+
+	old = sdata_dereference(sdata->u.ap.fils_discovery, sdata);
+	new = kzalloc(sizeof(*new) + params->tmpl_len, GFP_KERNEL);
+	if (!new)
+		return -ENOMEM;
+	new->len = params->tmpl_len;
+	memcpy(new->data, params->tmpl, params->tmpl_len);
+	rcu_assign_pointer(sdata->u.ap.fils_discovery, new);
+
+	if (old)
+		kfree_rcu(old, rcu_head);
+
+	return 0;
+}
+
 static int ieee80211_set_ftm_responder_params(
 				struct ieee80211_sub_if_data *sdata,
 				const u8 *lci, size_t lci_len,
@@ -1103,6 +1132,17 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
 	}
 	changed |= err;
 
+	if (params->fils_discovery.enabled) {
+		err = ieee80211_set_fils_discovery(sdata,
+						   &params->fils_discovery);
+		if (err < 0) {
+			ieee80211_vif_release_channel(sdata);
+			return err;
+		} else if (err == 0) {
+			changed |= BSS_CHANGED_FILS_DISCOVERY;
+		}
+	}
+
 	err = drv_start_ap(sdata->local, sdata);
 	if (err) {
 		old = sdata_dereference(sdata->u.ap.beacon, sdata);
@@ -1158,6 +1198,7 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
 	struct ieee80211_local *local = sdata->local;
 	struct beacon_data *old_beacon;
 	struct probe_resp *old_probe_resp;
+	struct fils_discovery_data *old_fils_discovery;
 	struct cfg80211_chan_def chandef;
 
 	sdata_assert_lock(sdata);
@@ -1166,6 +1207,8 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
 	if (!old_beacon)
 		return -ENOENT;
 	old_probe_resp = sdata_dereference(sdata->u.ap.probe_resp, sdata);
+	old_fils_discovery = sdata_dereference(sdata->u.ap.fils_discovery,
+					       sdata);
 
 	/* abort any running channel switch */
 	mutex_lock(&local->mtx);
@@ -1189,9 +1232,12 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
 	/* remove beacon and probe response */
 	RCU_INIT_POINTER(sdata->u.ap.beacon, NULL);
 	RCU_INIT_POINTER(sdata->u.ap.probe_resp, NULL);
+	RCU_INIT_POINTER(sdata->u.ap.fils_discovery, NULL);
 	kfree_rcu(old_beacon, rcu_head);
 	if (old_probe_resp)
 		kfree_rcu(old_probe_resp, rcu_head);
+	if (old_fils_discovery)
+		kfree_rcu(old_fils_discovery, rcu_head);
 
 	kfree(sdata->vif.bss_conf.ftmr_params);
 	sdata->vif.bss_conf.ftmr_params = NULL;
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index ec1a71ac65f2..479c1691630b 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -272,6 +272,12 @@ struct probe_resp {
 	u8 data[];
 };
 
+struct fils_discovery_data {
+	struct rcu_head rcu_head;
+	int len;
+	u8 data[0];
+};
+
 struct ps_data {
 	/* yes, this looks ugly, but guarantees that we can later use
 	 * bitmap_empty :)
@@ -287,6 +293,7 @@ struct ps_data {
 struct ieee80211_if_ap {
 	struct beacon_data __rcu *beacon;
 	struct probe_resp __rcu *probe_resp;
+	struct fils_discovery_data __rcu *fils_discovery;
 
 	/* to be used after channel switch. */
 	struct cfg80211_beacon_data *next_beacon;
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index e9ce658141f5..9c1044782561 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -4998,6 +4998,31 @@ struct sk_buff *ieee80211_proberesp_get(struct ieee80211_hw *hw,
 }
 EXPORT_SYMBOL(ieee80211_proberesp_get);
 
+struct sk_buff *ieee80211_get_fils_discovery_tmpl(struct ieee80211_hw *hw,
+						  struct ieee80211_vif *vif)
+{
+	struct sk_buff *skb = NULL;
+	struct fils_discovery_data *tmpl = NULL;
+	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
+
+	if (sdata->vif.type != NL80211_IFTYPE_AP)
+		return NULL;
+
+	rcu_read_lock();
+	tmpl = rcu_dereference(sdata->u.ap.fils_discovery);
+	if (!tmpl) {
+		rcu_read_unlock();
+		return NULL;
+	}
+
+	skb = dev_alloc_skb(tmpl->len);
+	if (skb)
+		skb_put_data(skb, tmpl->data, tmpl->len);
+	rcu_read_unlock();
+	return skb;
+}
+EXPORT_SYMBOL(ieee80211_get_fils_discovery_tmpl);
+
 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
 				     struct ieee80211_vif *vif)
 {
-- 
2.25.0