[PATCH v4 0/2] Unsolicited broadcast probe resp support

[PATCH v4 0/2] Unsolicited broadcast probe resp support

[Aloka Dixit]

Unsolicited broadcast probe response tranmission is used for in-band
discovery in 6GHz band (IEEE P802.11ax/D6.0 26.17.2.3.2, AP behavior for
fast passive scanning).

v4: Addressed comments.

v3: Rebased. Removed check for 6Ghz, drivers should add that check.

v2: Removed flag 'enabled' and changed 6GHz frequency range as per
    IEEE P802.11ax/D6.1.

Aloka Dixit (2):
  nl80211: Unsolicited broadcast probe response support
  mac80211: Unsolicited broadcast probe response support

 include/net/cfg80211.h       | 23 +++++++++++++++
 include/net/mac80211.h       | 24 +++++++++++++++
 include/uapi/linux/nl80211.h | 32 ++++++++++++++++++++
 net/mac80211/cfg.c           | 57 ++++++++++++++++++++++++++++++++----
 net/mac80211/debugfs.c       |  1 +
 net/mac80211/ieee80211_i.h   |  7 +++++
 net/mac80211/main.c          |  6 ++++
 net/mac80211/tx.c            | 29 ++++++++++++++++++
 net/wireless/nl80211.c       | 41 ++++++++++++++++++++++++++
 9 files changed, 214 insertions(+), 6 deletions(-)

-- 
2.25.0

[PATCH v4 1/2] nl80211: Unsolicited broadcast probe response support

[Aloka Dixit]

This patch adds new attributes to support unsolicited broadcast
probe response transmission used for in-band
discovery in 6GHz band (IEEE P802.11ax/D6.0 26.17.2.3.2, AP behavior for
fast passive scanning).
The new attribute, NL80211_ATTR_UNSOL_BCAST_PROBE_RESP, is nested which
supports following parameters:
(1) NL80211_UNSOL_BCAST_PROBE_RESP_INT - Packet interval
(2) NL80211_UNSOL_BCAST_PROBE_RESP_TMPL - Template data

Signed-off-by: Aloka Dixit <alokad@codeaurora.org>
---
v4: Addressed comments

 include/net/cfg80211.h       | 23 ++++++++++++++++++++
 include/uapi/linux/nl80211.h | 32 ++++++++++++++++++++++++++++
 net/wireless/nl80211.c       | 41 ++++++++++++++++++++++++++++++++++++
 3 files changed, 96 insertions(+)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index fc7e8807838d..e6f11c55f6bd 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1047,6 +1047,22 @@ struct cfg80211_acl_data {
 	struct mac_address mac_addrs[];
 };
 
+/**
+ * struct cfg80211_unsol_bcast_probe_resp - Unsolicited broadcast probe
+ *	response parameters in 6GHz.
+ *
+ * @interval: Packet interval in TUs. Maximum allowed is 20 TU, as mentioned
+ *	in IEEE P802.11ax/D6.0 26.17.2.3.2 - AP behavior for fast passive
+ *	scanning
+ * @tmpl_len: Template length
+ * @tmpl: Template data for probe response
+ */
+struct cfg80211_unsol_bcast_probe_resp {
+	u32 interval;
+	size_t tmpl_len;
+	const u8 *tmpl;
+};
+
 /**
  * enum cfg80211_ap_settings_flags - AP settings flags
  *
@@ -1094,6 +1110,7 @@ enum cfg80211_ap_settings_flags {
  * @he_obss_pd: OBSS Packet Detection settings
  * @he_bss_color: BSS Color settings
  * @he_oper: HE operation IE (or %NULL if HE isn't enabled)
+ * @unsol_bcast_probe_resp: Unsolicited broadcast probe response parameters
  */
 struct cfg80211_ap_settings {
 	struct cfg80211_chan_def chandef;
@@ -1124,6 +1141,7 @@ struct cfg80211_ap_settings {
 	u32 flags;
 	struct ieee80211_he_obss_pd he_obss_pd;
 	struct cfg80211_he_bss_color he_bss_color;
+	struct cfg80211_unsol_bcast_probe_resp unsol_bcast_probe_resp;
 };
 
 /**
@@ -4737,6 +4755,9 @@ struct wiphy_iftype_akm_suites {
  *	HE AP, in order to avoid compatibility issues.
  *	@support_mbssid must be set for this to have any effect.
  *
+ * @support_unsol_bcast_probe_resp: can HW support unsolicited broadcast
+ *	probe response transmission
+ *
  * @pmsr_capa: peer measurement capabilities
  *
  * @tid_config_support: describes the per-TID config support that the
@@ -4880,6 +4901,8 @@ struct wiphy {
 	u8 support_mbssid:1,
 	   support_only_he_mbssid:1;
 
+	u8 support_unsol_bcast_probe_resp:1;
+
 	const struct cfg80211_pmsr_capabilities *pmsr_capa;
 
 	struct {
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 4e6339ab1fce..91d0b6bd3671 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2505,6 +2505,10 @@ enum nl80211_commands {
  * @NL80211_ATTR_HE_6GHZ_CAPABILITY: HE 6 GHz Band Capability element (from
  *	association request when used with NL80211_CMD_NEW_STATION).
  *
+ * @NL80211_ATTR_UNSOL_BCAST_PROBE_RESP: Optional parameter to configure
+ *	unsolicited broadcast probe response. It is a nested attribute, see
+ *	&enum nl80211_unsol_bcast_probe_resp_attributes.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -2987,6 +2991,8 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_HE_6GHZ_CAPABILITY,
 
+	NL80211_ATTR_UNSOL_BCAST_PROBE_RESP,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
@@ -6922,4 +6928,30 @@ enum nl80211_iftype_akm_attributes {
 	NL80211_IFTYPE_AKM_ATTR_MAX = __NL80211_IFTYPE_AKM_ATTR_LAST - 1,
 };
 
+/**
+ * enum nl80211_unsol_bcast_probe_resp_attributes - Unsolicited broadcast probe
+ *	response configuration. Applicable only in 6GHz.
+ *
+ * @__NL80211_UNSOL_BCAST_PROBE_RESP_INVALID: Invalid
+ *
+ * @NL80211_UNSOL_BCAST_PROBE_RESP_INT: Maximum packet interval (u32, TU).
+ *	Allowed range: 0..20 (TU = Time Unit). IEEE P802.11ax/D6.0
+ *	26.17.2.3.2 (AP behavior for fast passive scanning).
+ * @NL80211_UNSOL_BCAST_PROBE_RESP_TMPL: Unsolicited broadcast probe response
+ *	frame template (binary).
+ *
+ * @__NL80211_UNSOL_BCAST_PROBE_RESP_LAST: Internal
+ * @NL80211_UNSOL_BCAST_PROBE_RESP_MAX: highest attribute
+ */
+enum nl80211_unsol_bcast_probe_resp_attributes {
+	__NL80211_UNSOL_BCAST_PROBE_RESP_INVALID,
+
+	NL80211_UNSOL_BCAST_PROBE_RESP_INT,
+	NL80211_UNSOL_BCAST_PROBE_RESP_TMPL,
+
+	/* keep last */
+	__NL80211_UNSOL_BCAST_PROBE_RESP_LAST,
+	NL80211_UNSOL_BCAST_PROBE_RESP_MAX =
+		__NL80211_UNSOL_BCAST_PROBE_RESP_LAST - 1
+};
 #endif /* __LINUX_NL80211_H */
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 263ae395ad44..0193c40b2caa 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -360,6 +360,13 @@ nl80211_tid_config_attr_policy[NL80211_TID_CONFIG_ATTR_MAX + 1] = {
 			NLA_POLICY_NESTED(nl80211_txattr_policy),
 };
 
+static const struct nla_policy
+unsol_bcast_probe_resp_policy[NL80211_UNSOL_BCAST_PROBE_RESP_MAX + 1] = {
+	[NL80211_UNSOL_BCAST_PROBE_RESP_INT] = NLA_POLICY_MAX(NLA_U32, 20),
+	[NL80211_UNSOL_BCAST_PROBE_RESP_TMPL] = { .type = NLA_BINARY,
+						  .len = IEEE80211_MAX_DATA_LEN }
+};
+
 static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[0] = { .strict_start_type = NL80211_ATTR_HE_OBSS_PD },
 	[NL80211_ATTR_WIPHY] = { .type = NLA_U32 },
@@ -658,6 +665,8 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 		.type = NLA_EXACT_LEN,
 		.len = sizeof(struct ieee80211_he_6ghz_capa),
 	},
+	[NL80211_ATTR_UNSOL_BCAST_PROBE_RESP] =
+		NLA_POLICY_NESTED(unsol_bcast_probe_resp_policy),
 };
 
 /* policy for the key attributes */
@@ -4721,6 +4730,30 @@ static int nl80211_parse_he_bss_color(struct nlattr *attrs,
 	return 0;
 }
 
+static int
+nl80211_parse_unsol_bcast_probe_resp(struct nlattr *attrs,
+				     struct cfg80211_ap_settings *params)
+{
+	struct nlattr *tb[NL80211_UNSOL_BCAST_PROBE_RESP_MAX + 1];
+	int ret;
+	struct cfg80211_unsol_bcast_probe_resp *presp =
+					&params->unsol_bcast_probe_resp;
+
+	ret = nla_parse_nested(tb, NL80211_UNSOL_BCAST_PROBE_RESP_MAX, attrs,
+			       unsol_bcast_probe_resp_policy, NULL);
+	if (ret)
+		return ret;
+
+	if (!tb[NL80211_UNSOL_BCAST_PROBE_RESP_INT] ||
+	    !tb[NL80211_UNSOL_BCAST_PROBE_RESP_TMPL])
+		return -EINVAL;
+
+	presp->tmpl = nla_data(tb[NL80211_UNSOL_BCAST_PROBE_RESP_TMPL]);
+	presp->tmpl_len = nla_len(tb[NL80211_UNSOL_BCAST_PROBE_RESP_TMPL]);
+	presp->interval = nla_get_u32(tb[NL80211_UNSOL_BCAST_PROBE_RESP_INT]);
+	return 0;
+}
+
 static void nl80211_check_ap_rate_selectors(struct cfg80211_ap_settings *params,
 					    const u8 *rates)
 {
@@ -5027,6 +5060,14 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 			return err;
 	}
 
+	if (info->attrs[NL80211_ATTR_UNSOL_BCAST_PROBE_RESP]) {
+		err = nl80211_parse_unsol_bcast_probe_resp(
+			info->attrs[NL80211_ATTR_UNSOL_BCAST_PROBE_RESP],
+			&params);
+		if (err)
+			return err;
+	}
+
 	nl80211_calculate_ap_params(&params);
 
 	if (info->attrs[NL80211_ATTR_EXTERNAL_AUTH_SUPPORT])
-- 
2.25.0

[PATCH v4 2/2] mac80211: Unsolicited broadcast probe response support

[Aloka Dixit]

This patch adds mac80211 support to configure unsolicited
broadcast probe response transmission for in-band discovery in 6GHz.

Changes include functions to store and retrieve probe response template,
and packet interval (0 - 20 TUs).
Setting interval to 0 disables the unsolicited broadcast probe response
transmission.

Signed-off-by: Aloka Dixit <alokad@codeaurora.org>
---
v4: Addressed comments

 include/net/mac80211.h     | 24 ++++++++++++++++
 net/mac80211/cfg.c         | 57 ++++++++++++++++++++++++++++++++++----
 net/mac80211/debugfs.c     |  1 +
 net/mac80211/ieee80211_i.h |  7 +++++
 net/mac80211/main.c        |  6 ++++
 net/mac80211/tx.c          | 29 +++++++++++++++++++
 6 files changed, 118 insertions(+), 6 deletions(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 11d5610d2ad5..f43f23b13ab6 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -317,6 +317,8 @@ 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_UNSOL_BCAST_PROBE_RESP: Unsolicited broadcast probe response
+ *	status changed.
  *
  */
 enum ieee80211_bss_change {
@@ -350,6 +352,7 @@ 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_UNSOL_BCAST_PROBE_RESP = 1<<30,
 
 	/* when adding here, make sure to change ieee80211_reconfig */
 };
@@ -607,6 +610,8 @@ 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
+ * @unsol_bcast_probe_resp_interval: Unsolicited broadcast probe response
+ *	interval.
  */
 struct ieee80211_bss_conf {
 	const u8 *bssid;
@@ -674,6 +679,7 @@ struct ieee80211_bss_conf {
 	} he_oper;
 	struct ieee80211_he_obss_pd he_obss_pd;
 	struct cfg80211_he_bss_color he_bss_color;
+	u32 unsol_bcast_probe_resp_interval;
 };
 
 /**
@@ -2325,6 +2331,9 @@ struct ieee80211_txq {
  *	aggregating MPDUs with the same keyid, allowing mac80211 to keep Tx
  *	A-MPDU sessions active while rekeying with Extended Key ID.
  *
+ * @IEEE80211_HW_SUPPORTS_UNSOL_BCAST_PROBE_RESP: Hardware/driver supports
+ *	unsolicited broadcast probe response transmission
+ *
  * @NUM_IEEE80211_HW_FLAGS: number of hardware flags, used for sizing arrays
  */
 enum ieee80211_hw_flags {
@@ -2377,6 +2386,7 @@ enum ieee80211_hw_flags {
 	IEEE80211_HW_SUPPORTS_MULTI_BSSID,
 	IEEE80211_HW_SUPPORTS_ONLY_HE_MULTI_BSSID,
 	IEEE80211_HW_AMPDU_KEYBORDER_SUPPORT,
+	IEEE80211_HW_SUPPORTS_UNSOL_BCAST_PROBE_RESP,
 
 	/* keep last, obviously */
 	NUM_IEEE80211_HW_FLAGS
@@ -6558,4 +6568,18 @@ u32 ieee80211_calc_tx_airtime(struct ieee80211_hw *hw,
  */
 bool ieee80211_set_hw_80211_encap(struct ieee80211_vif *vif, bool enable);
 
+/**
+ * ieee80211_get_unsol_bcast_probe_resp_tmpl - Get unsolicited broadcast
+ *     probe response 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: Unsolicited broadcast probe response template. %NULL on error.
+ */
+struct sk_buff *
+ieee80211_get_unsol_bcast_probe_resp_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..b4b028599cff 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_unsol_bcast_probe_resp(struct ieee80211_sub_if_data *sdata,
+				     struct cfg80211_unsol_bcast_probe_resp *params)
+{
+	struct unsol_bcast_probe_resp_data *new, *old = NULL;
+
+	if (!sdata->local->hw.wiphy->support_unsol_bcast_probe_resp)
+		return -EOPNOTSUPP;
+
+	if (!params->tmpl || !params->tmpl_len)
+		return -EINVAL;
+
+	old = sdata_dereference(sdata->u.ap.unsol_bcast_probe_resp, 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.unsol_bcast_probe_resp, new);
+
+	if (old)
+		kfree_rcu(old, rcu_head);
+
+	sdata->vif.bss_conf.unsol_bcast_probe_resp_interval =
+							params->interval;
+
+	return 0;
+}
+
 static int ieee80211_set_ftm_responder_params(
 				struct ieee80211_sub_if_data *sdata,
 				const u8 *lci, size_t lci_len,
@@ -1097,12 +1126,18 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
 	}
 
 	err = ieee80211_assign_beacon(sdata, &params->beacon, NULL);
-	if (err < 0) {
-		ieee80211_vif_release_channel(sdata);
-		return err;
-	}
+	if (err < 0)
+		goto error;
 	changed |= err;
 
+	if (params->unsol_bcast_probe_resp.interval) {
+		err = ieee80211_set_unsol_bcast_probe_resp(sdata,
+							   &params->unsol_bcast_probe_resp);
+		if (err < 0)
+			goto error;
+		changed |= BSS_CHANGED_UNSOL_BCAST_PROBE_RESP;
+	}
+
 	err = drv_start_ap(sdata->local, sdata);
 	if (err) {
 		old = sdata_dereference(sdata->u.ap.beacon, sdata);
@@ -1110,8 +1145,7 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
 		if (old)
 			kfree_rcu(old, rcu_head);
 		RCU_INIT_POINTER(sdata->u.ap.beacon, NULL);
-		ieee80211_vif_release_channel(sdata);
-		return err;
+		goto error;
 	}
 
 	ieee80211_recalc_dtim(local, sdata);
@@ -1122,6 +1156,10 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
 		netif_carrier_on(vlan->dev);
 
 	return 0;
+
+error:
+	ieee80211_vif_release_channel(sdata);
+	return err;
 }
 
 static int ieee80211_change_beacon(struct wiphy *wiphy, struct net_device *dev,
@@ -1158,6 +1196,7 @@ 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 unsol_bcast_probe_resp_data *old_unsol_bcast_probe_resp;
 	struct cfg80211_chan_def chandef;
 
 	sdata_assert_lock(sdata);
@@ -1166,6 +1205,9 @@ 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_unsol_bcast_probe_resp =
+		sdata_dereference(sdata->u.ap.unsol_bcast_probe_resp,
+				  sdata);
 
 	/* abort any running channel switch */
 	mutex_lock(&local->mtx);
@@ -1189,9 +1231,12 @@ 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.unsol_bcast_probe_resp, NULL);
 	kfree_rcu(old_beacon, rcu_head);
 	if (old_probe_resp)
 		kfree_rcu(old_probe_resp, rcu_head);
+	if (old_unsol_bcast_probe_resp)
+		kfree_rcu(old_unsol_bcast_probe_resp, rcu_head);
 
 	kfree(sdata->vif.bss_conf.ftmr_params);
 	sdata->vif.bss_conf.ftmr_params = NULL;
diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index 54080290d6e2..18047db2e56f 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -408,6 +408,7 @@ static const char *hw_flag_names[] = {
 	FLAG(SUPPORTS_MULTI_BSSID),
 	FLAG(SUPPORTS_ONLY_HE_MULTI_BSSID),
 	FLAG(AMPDU_KEYBORDER_SUPPORT),
+	FLAG(SUPPORTS_UNSOL_BCAST_PROBE_RESP),
 #undef FLAG
 };
 
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index ec1a71ac65f2..b54108ef3560 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -272,6 +272,12 @@ struct probe_resp {
 	u8 data[];
 };
 
+struct unsol_bcast_probe_resp_data {
+	struct rcu_head rcu_head;
+	int len;
+	u8 data[];
+};
+
 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 unsol_bcast_probe_resp_data __rcu *unsol_bcast_probe_resp;
 
 	/* to be used after channel switch. */
 	struct cfg80211_beacon_data *next_beacon;
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index b4a2efe8e83a..0c326d5616ae 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -1168,6 +1168,12 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
 				WLAN_EXT_CAPA3_MULTI_BSSID_SUPPORT;
 	}
 
+	/* mac80211 supports unsolicited broadcast probe response
+	 * transmission, if the driver supports it
+	 */
+	if (ieee80211_hw_check(&local->hw, SUPPORTS_UNSOL_BCAST_PROBE_RESP))
+		local->hw.wiphy->support_unsol_bcast_probe_resp = true;
+
 	local->hw.wiphy->max_num_csa_counters = IEEE80211_MAX_CSA_COUNTERS_NUM;
 
 	/*
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index e9ce658141f5..49ca7227c9fa 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -4998,6 +4998,35 @@ struct sk_buff *ieee80211_proberesp_get(struct ieee80211_hw *hw,
 }
 EXPORT_SYMBOL(ieee80211_proberesp_get);
 
+struct sk_buff *
+ieee80211_get_unsol_bcast_probe_resp_tmpl(struct ieee80211_hw *hw,
+					  struct ieee80211_vif *vif)
+{
+	struct sk_buff *skb = NULL;
+	struct unsol_bcast_probe_resp_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.unsol_bcast_probe_resp);
+	if (!tmpl) {
+		rcu_read_unlock();
+		return NULL;
+	}
+
+	skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom + tmpl->len);
+	if (skb) {
+		skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
+		skb_put_data(skb, tmpl->data, tmpl->len);
+	}
+
+	rcu_read_unlock();
+	return skb;
+}
+EXPORT_SYMBOL(ieee80211_get_unsol_bcast_probe_resp_tmpl);
+
 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
 				     struct ieee80211_vif *vif)
 {
-- 
2.25.0

Re: [PATCH v4 0/2] Unsolicited broadcast probe resp support

[Johannes Berg]

This has the same issue as the FILS changes with the feature flags etc.

johannes