nl80211: Unsolicited broadcast probe response support

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>
Link: https://lore.kernel.org/r/010101747a946698-aac263ae-2ed3-4dab-9590-0bc7131214e1-000000@us-west-2.amazonses.comSigned-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/cfg80211.h

@@ -1099,6 +1099,22 @@ 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
  *
@@ -1147,6 +1163,7 @@ 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;
@@ -1178,6 +1195,7 @@ 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;
 };
 
 /**

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,
@@ -5876,6 +5882,9 @@ 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.
  */
@@ -5935,6 +5944,7 @@ 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,
@@ -7063,4 +7073,30 @@ 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 */

net/wireless/nl80211.c

@@ -385,6 +385,13 @@ 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 },
@@ -695,6 +702,8 @@ 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 */
@@ -4915,6 +4924,35 @@ 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)
 {
@@ -5231,6 +5269,14 @@ 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])