[PATCH v5 1/2] nl80211: Unsolicited broadcast probe response support

[PATCH v5 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_ATTR_INT - Packet interval
(2) NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_TMPL - Template data

Signed-off-by: Aloka Dixit <alokad@codeaurora.org>
---
 include/net/cfg80211.h       | 18 ++++++++++++++
 include/uapi/linux/nl80211.h | 36 +++++++++++++++++++++++++++
 net/wireless/nl80211.c       | 48 ++++++++++++++++++++++++++++++++++++
 3 files changed, 102 insertions(+)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 2011b2434baf..e550f91450d0 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1084,6 +1084,22 @@ struct cfg80211_fils_discovery {
 	const u8 *tmpl;
 };
 
+/**
+ * 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
  *
@@ -1132,6 +1148,7 @@ enum cfg80211_ap_settings_flags {
  * @he_bss_color: BSS Color settings
  * @he_oper: HE operation IE (or %NULL if HE isn't enabled)
  * @fils_discovery: FILS discovery transmission parameters
+ * @unsol_bcast_probe_resp: Unsolicited broadcast probe response parameters
  */
 struct cfg80211_ap_settings {
 	struct cfg80211_chan_def chandef;
@@ -1163,6 +1180,7 @@ struct cfg80211_ap_settings {
 	struct ieee80211_he_obss_pd he_obss_pd;
 	struct cfg80211_he_bss_color he_bss_color;
 	struct cfg80211_fils_discovery fils_discovery;
+	struct cfg80211_unsol_bcast_probe_resp unsol_bcast_probe_resp;
 };
 
 /**
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index d6b6c5103387..0c7b56eb5ce2 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2517,6 +2517,10 @@ enum nl80211_commands {
  *	discovery. It is a nested attribute, see
  *	&enum nl80211_fils_discovery_attributes.
  *
+ * @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
@@ -3001,6 +3005,8 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_FILS_DISCOVERY,
 
+	NL80211_ATTR_UNSOL_BCAST_PROBE_RESP,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
@@ -5861,6 +5867,9 @@ enum nl80211_feature_flags {
  * @NL80211_EXT_FEATURE_FILS_DISCOVERY: Driver/device supports FILS discovery
  *	frames transmission
  *
+ * @NL80211_EXT_FEATURE_UNSOL_BCAST_PROBE_RESP: Driver/device supports
+ *	unsolicited broadcast probe response transmission
+ *
  * @NUM_NL80211_EXT_FEATURES: number of extended features.
  * @MAX_NL80211_EXT_FEATURES: highest extended feature index.
  */
@@ -5920,6 +5929,7 @@ enum nl80211_ext_feature_index {
 	NL80211_EXT_FEATURE_4WAY_HANDSHAKE_AP_PSK,
 	NL80211_EXT_FEATURE_SAE_OFFLOAD_AP,
 	NL80211_EXT_FEATURE_FILS_DISCOVERY,
+	NL80211_EXT_FEATURE_UNSOL_BCAST_PROBE_RESP,
 
 	/* add new features before the definition below */
 	NUM_NL80211_EXT_FEATURES,
@@ -7048,4 +7058,30 @@ enum nl80211_fils_discovery_attributes {
  */
 #define NL80211_FILS_DISCOVERY_TMPL_MIN_LEN 42
 
+/**
+ * enum nl80211_unsol_bcast_probe_resp_attributes - Unsolicited broadcast probe
+ *	response configuration. Applicable only in 6GHz.
+ *
+ * @__NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_INVALID: Invalid
+ *
+ * @NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_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_ATTR_TMPL: Unsolicited broadcast probe response
+ *	frame template (binary).
+ *
+ * @__NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_LAST: Internal
+ * @NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_MAX: highest attribute
+ */
+enum nl80211_unsol_bcast_probe_resp_attributes {
+	__NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_INVALID,
+
+	NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_INT,
+	NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_TMPL,
+
+	/* keep last */
+	__NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_LAST,
+	NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_MAX =
+		__NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_LAST - 1
+};
 #endif /* __LINUX_NL80211_H */
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index c6dcd81fd643..333ba0b6df68 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -376,6 +376,13 @@ nl80211_fils_discovery_policy[NL80211_FILS_DISCOVERY_ATTR_MAX + 1] = {
 			 IEEE80211_MAX_DATA_LEN),
 };
 
+static const struct nla_policy
+nl80211_unsol_bcast_probe_resp_policy[NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_MAX + 1] = {
+	[NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_INT] = NLA_POLICY_MAX(NLA_U32, 20),
+	[NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_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 },
@@ -686,6 +693,8 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 		NLA_POLICY_EXACT_LEN(sizeof(struct ieee80211_he_6ghz_capa)),
 	[NL80211_ATTR_FILS_DISCOVERY] =
 		NLA_POLICY_NESTED(nl80211_fils_discovery_policy),
+	[NL80211_ATTR_UNSOL_BCAST_PROBE_RESP] =
+		NLA_POLICY_NESTED(nl80211_unsol_bcast_probe_resp_policy),
 };
 
 /* policy for the key attributes */
@@ -4892,6 +4901,36 @@ static int nl80211_parse_fils_discovery(struct cfg80211_registered_device *rdev,
 	return 0;
 }
 
+static int
+nl80211_parse_unsol_bcast_probe_resp(struct cfg80211_registered_device *rdev,
+				     struct nlattr *attrs,
+				     struct cfg80211_ap_settings *params)
+{
+	struct nlattr *tb[NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_MAX + 1];
+	int ret;
+	struct cfg80211_unsol_bcast_probe_resp *presp =
+					&params->unsol_bcast_probe_resp;
+
+	if (!wiphy_ext_feature_isset(&rdev->wiphy,
+				     NL80211_EXT_FEATURE_UNSOL_BCAST_PROBE_RESP)) {
+		return -EINVAL;
+	}
+
+	ret = nla_parse_nested(tb, NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_MAX,
+			       attrs, NULL, NULL);
+	if (ret)
+		return ret;
+
+	if (!tb[NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_INT] ||
+	    !tb[NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_TMPL])
+		return -EINVAL;
+
+	presp->tmpl = nla_data(tb[NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_TMPL]);
+	presp->tmpl_len = nla_len(tb[NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_TMPL]);
+	presp->interval = nla_get_u32(tb[NL80211_UNSOL_BCAST_PROBE_RESP_ATTR_INT]);
+	return 0;
+}
+
 static void nl80211_check_ap_rate_selectors(struct cfg80211_ap_settings *params,
 					    const u8 *rates)
 {
@@ -5208,6 +5247,15 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 			goto out;
 	}
 
+	if (info->attrs[NL80211_ATTR_UNSOL_BCAST_PROBE_RESP]) {
+		err = nl80211_parse_unsol_bcast_probe_resp(
+			rdev,
+			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 v5 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>
---
 include/net/mac80211.h     | 20 +++++++++++++++++++
 net/mac80211/cfg.c         | 41 ++++++++++++++++++++++++++++++++++++++
 net/mac80211/ieee80211_i.h |  7 +++++++
 net/mac80211/tx.c          | 29 +++++++++++++++++++++++++++
 4 files changed, 97 insertions(+)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index a8defc2954e2..517528c5f2e5 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -318,6 +318,8 @@ struct ieee80211_vif_chanctx_switch {
  * @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.
+ * @BSS_CHANGED_UNSOL_BCAST_PROBE_RESP: Unsolicited broadcast probe response
+ *	status changed.
  *
  */
 enum ieee80211_bss_change {
@@ -352,6 +354,7 @@ enum ieee80211_bss_change {
 	BSS_CHANGED_HE_OBSS_PD		= 1<<28,
 	BSS_CHANGED_HE_BSS_COLOR	= 1<<29,
 	BSS_CHANGED_FILS_DISCOVERY      = 1<<30,
+	BSS_CHANGED_UNSOL_BCAST_PROBE_RESP = 1<<31,
 
 	/* when adding here, make sure to change ieee80211_reconfig */
 };
@@ -622,6 +625,8 @@ struct ieee80211_fils_discovery {
  * @he_obss_pd: OBSS Packet Detection parameters.
  * @he_bss_color: BSS coloring settings, if BSS supports HE
  * @fils_discovery: FILS discovery configuration
+ * @unsol_bcast_probe_resp_interval: Unsolicited broadcast probe response
+ *	interval.
  */
 struct ieee80211_bss_conf {
 	const u8 *bssid;
@@ -690,6 +695,7 @@ struct ieee80211_bss_conf {
 	struct ieee80211_he_obss_pd he_obss_pd;
 	struct cfg80211_he_bss_color he_bss_color;
 	struct ieee80211_fils_discovery fils_discovery;
+	u32 unsol_bcast_probe_resp_interval;
 };
 
 /**
@@ -6620,4 +6626,18 @@ bool ieee80211_set_hw_80211_encap(struct ieee80211_vif *vif, bool enable);
  */
 struct sk_buff *ieee80211_get_fils_discovery_tmpl(struct ieee80211_hw *hw,
 						  struct ieee80211_vif *vif);
+
+/**
+ * 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 5bcaf6b01e7e..6d249cca8010 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -864,6 +864,32 @@ static int ieee80211_set_fils_discovery(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 (!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,
@@ -1138,6 +1164,14 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
 		changed |= BSS_CHANGED_FILS_DISCOVERY;
 	}
 
+	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);
@@ -1197,6 +1231,7 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
 	struct beacon_data *old_beacon;
 	struct probe_resp *old_probe_resp;
 	struct fils_discovery_data *old_fils_discovery;
+	struct unsol_bcast_probe_resp_data *old_unsol_bcast_probe_resp;
 	struct cfg80211_chan_def chandef;
 
 	sdata_assert_lock(sdata);
@@ -1207,6 +1242,9 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
 	old_probe_resp = sdata_dereference(sdata->u.ap.probe_resp, sdata);
 	old_fils_discovery = sdata_dereference(sdata->u.ap.fils_discovery,
 					       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);
@@ -1231,11 +1269,14 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
 	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);
+	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_fils_discovery)
 		kfree_rcu(old_fils_discovery, 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/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index e5b934c9eed3..8016a73159cc 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -277,6 +277,12 @@ struct fils_discovery_data {
 	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 :)
@@ -293,6 +299,7 @@ struct ieee80211_if_ap {
 	struct beacon_data __rcu *beacon;
 	struct probe_resp __rcu *probe_resp;
 	struct fils_discovery_data __rcu *fils_discovery;
+	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/tx.c b/net/mac80211/tx.c
index f82caf113b1a..127903742419 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -5028,6 +5028,35 @@ struct sk_buff *ieee80211_get_fils_discovery_tmpl(struct ieee80211_hw *hw,
 }
 EXPORT_SYMBOL(ieee80211_get_fils_discovery_tmpl);
 
+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