[PATCH] Advertise 6G RNR IE from nr_db also in probe response

[Nikita Chernikov]

From ccf6b23c40b4a05d10147c2bddc19e59ba751c73 Mon Sep 17 00:00:00 2001
From: Nikita Chernikov <nchernikov at maxlinear.com>
Date: Tue, 2 Apr 2024 14:45:39 +0300
Subject: [PATCH] Advertise 6G RNR IE from nr_db also in probe response
To: hostap at lists.infradead.org

Currently, RNR elements built from nr_db are only advertised in beacon.
To comply with 11AX standard, RNR IE of 6G should also be advertised in probe response.
Also, replace magic numbers with definitions in nr_db RNR element construction.

Signed-off-by: Nikita Chernikov <nchernikov at maxlinear.com>
---
 src/ap/ieee802_11.c  | 39 +++++++++++++++++++++++++--------------
 src/ap/neighbor_db.h |  4 ++++
 2 files changed, 29 insertions(+), 14 deletions(-)

diff --git a/src/ap/ieee802_11.c b/src/ap/ieee802_11.c
index fcb2d14cf..a992379b6 100644
--- a/src/ap/ieee802_11.c
+++ b/src/ap/ieee802_11.c
@@ -50,6 +50,7 @@
 #include "ieee802_11.h"
 #include "dfs.h"
 #include "mbo_ap.h"
+#include "neighbor_db.h"
 #include "rrm.h"
 #include "taxonomy.h"
 #include "fils_hlp.h"
@@ -7301,14 +7302,19 @@ u8 * hostapd_eid_wb_chsw_wrapper(struct hostapd_data *hapd, u8 *eid)
 
 
 static size_t hostapd_eid_nr_db_len(struct hostapd_data *hapd,
-				    size_t *current_len)
+				    size_t *current_len, unsigned int frame_stype)
 {
 	struct hostapd_neighbor_entry *nr;
 	size_t total_len = 0, len = *current_len;
 
 	dl_list_for_each(nr, &hapd->nr_db, struct hostapd_neighbor_entry,
 			 list) {
-		if (!nr->nr || wpabuf_len(nr->nr) < 12)
+		if (!nr->nr || wpabuf_len(nr->nr) < HOSTAPD_NEIGHBOR_DB_NR_MAX_LEN)
+			continue;
+
+		/* Skip building RNR element from nr_db for non 6G VAPs in probe response */
+		if (!(is_6ghz_op_class(wpabuf_head_u8(nr->nr)[HOSTAPD_NEIGHBOR_DB_NR_OPCLASS])) &&
+			(frame_stype == WLAN_FC_STYPE_PROBE_RESP))
 			continue;
 
 		if (nr->short_ssid == hapd->conf->ssid.short_ssid)
@@ -7484,11 +7490,11 @@ size_t hostapd_eid_rnr_len(struct hostapd_data *hapd, u32 type)
 
 	switch (type) {
 	case WLAN_FC_STYPE_BEACON:
-		if (hapd->conf->rnr)
-			total_len += hostapd_eid_nr_db_len(hapd, &current_len);
 		/* fallthrough */
-
 	case WLAN_FC_STYPE_PROBE_RESP:
+		if (hapd->conf->rnr)
+			total_len += hostapd_eid_nr_db_len(hapd, &current_len, type);
+
 		if (mode == COLOCATED_LOWER_BAND || ap_mld)
 			total_len +=
 				hostapd_eid_rnr_multi_iface_len(hapd,
@@ -7517,7 +7523,7 @@ size_t hostapd_eid_rnr_len(struct hostapd_data *hapd, u32 type)
 
 
 static u8 * hostapd_eid_nr_db(struct hostapd_data *hapd, u8 *eid,
-			      size_t *current_len)
+			      size_t *current_len, unsigned int frame_stype)
 {
 	struct hostapd_neighbor_entry *nr;
 	size_t len = *current_len;
@@ -7525,7 +7531,12 @@ static u8 * hostapd_eid_nr_db(struct hostapd_data *hapd, u8 *eid,
 
 	dl_list_for_each(nr, &hapd->nr_db, struct hostapd_neighbor_entry,
 			 list) {
-		if (!nr->nr || wpabuf_len(nr->nr) < 12)
+		if (!nr->nr || wpabuf_len(nr->nr) < HOSTAPD_NEIGHBOR_DB_NR_MAX_LEN)
+			continue;
+
+		/* Skip building RNR element from nr_db for non 6G VAPs in probe response */
+		if (!(is_6ghz_op_class(wpabuf_head_u8(nr->nr)[HOSTAPD_NEIGHBOR_DB_NR_OPCLASS])) &&
+			(frame_stype == WLAN_FC_STYPE_PROBE_RESP))
 			continue;
 
 		if (nr->short_ssid == hapd->conf->ssid.short_ssid)
@@ -7544,9 +7555,9 @@ static u8 * hostapd_eid_nr_db(struct hostapd_data *hapd, u8 *eid,
 		/* TBTT Information Length */
 		*eid++ = RNR_TBTT_INFO_LEN;
 		/* Operating Class */
-		*eid++ = wpabuf_head_u8(nr->nr)[10];
+		*eid++ = wpabuf_head_u8(nr->nr)[HOSTAPD_NEIGHBOR_DB_NR_OPCLASS];
 		/* Channel Number */
-		*eid++ = wpabuf_head_u8(nr->nr)[11];
+		*eid++ = wpabuf_head_u8(nr->nr)[HOSTAPD_NEIGHBOR_DB_NR_CHANNEL];
 		len += RNR_TBTT_HEADER_LEN;
 		/* TBTT Information Set */
 		/* TBTT Information field */
@@ -7758,11 +7769,11 @@ u8 * hostapd_eid_rnr(struct hostapd_data *hapd, u8 *eid, u32 type)
 
 	switch (type) {
 	case WLAN_FC_STYPE_BEACON:
-		if (hapd->conf->rnr)
-			eid = hostapd_eid_nr_db(hapd, eid, &current_len);
 		/* fallthrough */
-
 	case WLAN_FC_STYPE_PROBE_RESP:
+		if (hapd->conf->rnr)
+			eid = hostapd_eid_nr_db(hapd, eid, &current_len, type);
+
 		if (mode == COLOCATED_LOWER_BAND || ap_mld)
 			eid = hostapd_eid_rnr_multi_iface(hapd, eid,
 							  &current_len);
@@ -8087,7 +8098,7 @@ u8 * hostapd_eid_mbssid(struct hostapd_data *hapd, u8 *eid, u8 *end,
 	}
 
 	add_rnr = hapd->iconf->mbssid == ENHANCED_MBSSID_ENABLED &&
-		frame_stype == WLAN_FC_STYPE_BEACON &&
+		((frame_stype == WLAN_FC_STYPE_BEACON) || (frame_stype == WLAN_FC_STYPE_PROBE_RESP)) &&
 		rnr_eid && rnr_count && rnr_offset && rnr_len;
 
 	while (bss_index < hapd->iface->num_bss) {
@@ -8128,7 +8139,7 @@ u8 * hostapd_eid_mbssid(struct hostapd_data *hapd, u8 *eid, u8 *end,
 		cur_len = 0;
 
 		if (hapd->conf->rnr)
-			rnr_eid = hostapd_eid_nr_db(hapd, rnr_eid, &cur_len);
+			rnr_eid = hostapd_eid_nr_db(hapd, rnr_eid, &cur_len, frame_stype);
 		if (get_colocation_mode(hapd) == COLOCATED_LOWER_BAND)
 			rnr_eid = hostapd_eid_rnr_multi_iface(hapd, rnr_eid,
 							      &cur_len);
diff --git a/src/ap/neighbor_db.h b/src/ap/neighbor_db.h
index 53f714203..621b94187 100644
--- a/src/ap/neighbor_db.h
+++ b/src/ap/neighbor_db.h
@@ -10,6 +10,10 @@
 #ifndef NEIGHBOR_DB_H
 #define NEIGHBOR_DB_H
 
+#define HOSTAPD_NEIGHBOR_DB_NR_OPCLASS 10
+#define HOSTAPD_NEIGHBOR_DB_NR_CHANNEL 11
+#define HOSTAPD_NEIGHBOR_DB_NR_MAX_LEN 12
+
 struct hostapd_neighbor_entry *
 hostapd_neighbor_get(struct hostapd_data *hapd, const u8 *bssid,
 		     const struct wpa_ssid_value *ssid);
-- 
2.17.1