[1/2] cfg80211: support RNR for EMA AP

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 11a370e64143..bfde9e909c06 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1172,6 +1172,23 @@  struct cfg80211_mbssid_elems {
 	} elem[];
 };
 
+/**
+ * struct cfg80211_rnr_elems - Reduced neighbor report (RNR) elements
+ *
+ * @cnt: Number of elements in array %elems.
+ *
+ * @elem: Array of RNR element(s) to be added into Beacon frames.
+ * @elem.data: Data for RNR elements.
+ * @elem.len: Length of data.
+ */
+struct cfg80211_rnr_elems {
+	u8 cnt;
+	struct {
+		const u8 *data;
+		size_t len;
+	} elem[];
+};
+
 /**
  * struct cfg80211_beacon_data - beacon data
  * @link_id: the link ID for the AP MLD link sending this beacon
@@ -1192,6 +1209,7 @@  struct cfg80211_mbssid_elems {
  * @probe_resp_len: length of probe response template (@probe_resp)
  * @probe_resp: probe response template (AP mode only)
  * @mbssid_ies: multiple BSSID elements
+ * @rnr_ies: reduced neighbor report elements
  * @ftm_responder: enable FTM responder functionality; -1 for no change
  *	(which also implies no change in LCI/civic location data)
  * @lci: Measurement Report element content, starting with Measurement Token
@@ -1215,6 +1233,7 @@  struct cfg80211_beacon_data {
 	const u8 *lci;
 	const u8 *civicloc;
 	struct cfg80211_mbssid_elems *mbssid_ies;
+	struct cfg80211_rnr_elems *rnr_ies;
 	s8 ftm_responder;
 
 	size_t head_len, tail_len;
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index c14a91bbca7c..2623fb4542ec 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2751,6 +2751,17 @@  enum nl80211_commands {
  *	the incoming frame RX timestamp.
  * @NL80211_ATTR_TD_BITMAP: Transition Disable bitmap, for subsequent
  *	(re)associations.
+ * @NL80211_ATTR_EMA_RNR_ELEMS: Optional nested attribute for
+ *	reduced neighbor report (RNR) elements. This attribute can be used
+ *	only when NL80211_MBSSID_CONFIG_ATTR_EMA is enabled.
+ *	Userspace is responsible for splitting the RNR into multiple
+ *	elements such that each element excludes the non-transmitting
+ *	profiles already included in the MBSSID element
+ *	(%NL80211_ATTR_MBSSID_ELEMS) at the same index. Each EMA beacon
+ *	will be generated by adding MBSSID and RNR elements at the same
+ *	index. If the userspace includes more RNR elements than number of
+ *	MBSSID elements then these will be added in every EMA beacon.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -3280,6 +3291,8 @@  enum nl80211_attrs {
 	NL80211_ATTR_RX_HW_TIMESTAMP,
 	NL80211_ATTR_TD_BITMAP,
 
+	NL80211_ATTR_EMA_RNR_ELEMS,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 148f66edb015..ee0f3bff989d 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -805,6 +805,7 @@  static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[NL80211_ATTR_MLD_ADDR] = NLA_POLICY_EXACT_LEN(ETH_ALEN),
 	[NL80211_ATTR_MLO_SUPPORT] = { .type = NLA_FLAG },
 	[NL80211_ATTR_MAX_NUM_AKM_SUITES] = { .type = NLA_REJECT },
+	[NL80211_ATTR_EMA_RNR_ELEMS] = { .type = NLA_NESTED },
 };
 
 /* policy for the key attributes */
@@ -5391,6 +5392,30 @@  nl80211_parse_mbssid_elems(struct wiphy *wiphy, struct nlattr *attrs)
 	return elems;
 }
 
+static struct cfg80211_rnr_elems *nl80211_parse_rnr_elems(struct wiphy *wiphy,
+							  struct nlattr *attrs)
+{
+	struct nlattr *nl_elems;
+	struct cfg80211_rnr_elems *elems;
+	int rem_elems;
+	u8 i = 0, num_elems = 0;
+
+	nla_for_each_nested(nl_elems, attrs, rem_elems)
+		num_elems++;
+
+	elems = kzalloc(struct_size(elems, elem, num_elems), GFP_KERNEL);
+	if (!elems)
+		return ERR_PTR(-ENOMEM);
+
+	nla_for_each_nested(nl_elems, attrs, rem_elems) {
+		elems->elem[i].data = nla_data(nl_elems);
+		elems->elem[i].len = nla_len(nl_elems);
+		i++;
+	}
+	elems->cnt = num_elems;
+	return elems;
+}
+
 static int nl80211_parse_he_bss_color(struct nlattr *attrs,
 				      struct cfg80211_he_bss_color *he_bss_color)
 {
@@ -5514,6 +5539,20 @@  static int nl80211_parse_beacon(struct cfg80211_registered_device *rdev,
 			return PTR_ERR(mbssid);
 
 		bcn->mbssid_ies = mbssid;
+
+		if (bcn->mbssid_ies && attrs[NL80211_ATTR_EMA_RNR_ELEMS]) {
+			struct cfg80211_rnr_elems *rnr =
+				nl80211_parse_rnr_elems(&rdev->wiphy,
+							attrs[NL80211_ATTR_EMA_RNR_ELEMS]);
+
+			if (IS_ERR(rnr))
+				return PTR_ERR(rnr);
+
+			if (rnr && rnr->cnt < bcn->mbssid_ies->cnt)
+				return -EINVAL;
+
+			bcn->rnr_ies = rnr;
+		}
 	}
 
 	return 0;
@@ -6018,6 +6057,11 @@  static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 			goto out_unlock;
 	}
 
+	if (!params->mbssid_config.ema && params->beacon.rnr_ies) {
+		err = -EINVAL;
+		goto out_unlock;
+	}
+
 	err = nl80211_calculate_ap_params(params);
 	if (err)
 		goto out_unlock;
@@ -6057,6 +6101,7 @@  static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 	    params->mbssid_config.tx_wdev->netdev &&
 	    params->mbssid_config.tx_wdev->netdev != dev)
 		dev_put(params->mbssid_config.tx_wdev->netdev);
+	kfree(params->beacon.rnr_ies);
 	kfree(params);
 
 	return err;
@@ -6091,6 +6136,7 @@  static int nl80211_set_beacon(struct sk_buff *skb, struct genl_info *info)
 
 out:
 	kfree(params.mbssid_ies);
+	kfree(params.rnr_ies);
 	return err;
 }
 
@@ -10061,6 +10107,8 @@  static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info)
 free:
 	kfree(params.beacon_after.mbssid_ies);
 	kfree(params.beacon_csa.mbssid_ies);
+	kfree(params.beacon_after.rnr_ies);
+	kfree(params.beacon_csa.rnr_ies);
 	kfree(csa_attrs);
 	return err;
 }
@@ -15832,6 +15880,8 @@  static int nl80211_color_change(struct sk_buff *skb, struct genl_info *info)
 out:
 	kfree(params.beacon_next.mbssid_ies);
 	kfree(params.beacon_color_change.mbssid_ies);
+	kfree(params.beacon_next.rnr_ies);
+	kfree(params.beacon_color_change.rnr_ies);
 	kfree(tb);
 	return err;
 }