[PATCH v2 2/5] bss_coloring: add the code required to generate the CCA IE

[Ryder Lee]

From: John Crispin <john at phrozen.org>

This IE is similar to the CSA one. It contains a counter and the target
color. Once the counter expired, the change to the new color happens.

Just note the current implementation is based on CCA counter attributes
that only takes beacon and prob_resp into account, as for the assoc_resp
frames will be added in the future patches.

Tested-by: Peter Chiu <chui-hao.chiu at mediatek.com>
Co-developed-by: Lorenzo Bianconi <lorenzo at kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo at kernel.org>
Signed-off-by: John Crispin <john at phrozen.org>
Signed-off-by: Ryder Lee <ryder.lee at mediatek.com>
---
changes since v2 -
- fix the position of CCA IE.
---
 src/ap/beacon.c              | 18 ++++++++++++++++++
 src/ap/ieee802_11.h          |  1 +
 src/ap/ieee802_11_he.c       | 14 ++++++++++++++
 src/common/ieee802_11_defs.h |  1 +
 4 files changed, 34 insertions(+)

diff --git a/src/ap/beacon.c b/src/ap/beacon.c
index 15fc2b3db..794229527 100644
--- a/src/ap/beacon.c
+++ b/src/ap/beacon.c
@@ -578,8 +578,17 @@ static u8 * hostapd_gen_probe_resp(struct hostapd_data *hapd,
 
 #ifdef CONFIG_IEEE80211AX
 	if (hapd->iconf->ieee80211ax && !hapd->conf->disable_11ax) {
+		u8 *cca_pos;
+
 		pos = hostapd_eid_he_capab(hapd, pos, IEEE80211_MODE_AP);
 		pos = hostapd_eid_he_operation(hapd, pos);
+
+		/* CCA IE */
+		cca_pos = hostapd_eid_cca(hapd, pos);
+		if (cca_pos != pos)
+			hapd->cca_c_off_proberesp = cca_pos - (u8 *) resp - 2;
+		pos = cca_pos;
+
 		pos = hostapd_eid_spatial_reuse(hapd, pos);
 		pos = hostapd_eid_he_mu_edca_parameter_set(hapd, pos);
 		pos = hostapd_eid_he_6ghz_band_cap(hapd, pos);
@@ -1567,9 +1576,18 @@ int ieee802_11_build_ap_params(struct hostapd_data *hapd,
 
 #ifdef CONFIG_IEEE80211AX
 	if (hapd->iconf->ieee80211ax && !hapd->conf->disable_11ax) {
+		u8 *cca_pos;
+
 		tailpos = hostapd_eid_he_capab(hapd, tailpos,
 					       IEEE80211_MODE_AP);
 		tailpos = hostapd_eid_he_operation(hapd, tailpos);
+
+		/* CCA IE */
+		cca_pos = hostapd_eid_cca(hapd, tailpos);
+		if (cca_pos != tailpos)
+			hapd->cca_c_off_beacon = cca_pos - tail - 2;
+		tailpos = cca_pos;
+
 		tailpos = hostapd_eid_spatial_reuse(hapd, tailpos);
 		tailpos = hostapd_eid_he_mu_edca_parameter_set(hapd, tailpos);
 		tailpos = hostapd_eid_he_6ghz_band_cap(hapd, tailpos);
diff --git a/src/ap/ieee802_11.h b/src/ap/ieee802_11.h
index ea8c60846..65308ff34 100644
--- a/src/ap/ieee802_11.h
+++ b/src/ap/ieee802_11.h
@@ -100,6 +100,7 @@ u16 copy_sta_he_6ghz_capab(struct hostapd_data *hapd, struct sta_info *sta,
 			   const u8 *he_6ghz_capab);
 int hostapd_get_he_twt_responder(struct hostapd_data *hapd,
 				 enum ieee80211_op_mode mode);
+u8 * hostapd_eid_cca(struct hostapd_data *hapd, u8 *eid);
 void hostapd_tx_status(struct hostapd_data *hapd, const u8 *addr,
 		       const u8 *buf, size_t len, int ack);
 void hostapd_eapol_tx_status(struct hostapd_data *hapd, const u8 *dst,
diff --git a/src/ap/ieee802_11_he.c b/src/ap/ieee802_11_he.c
index 6cd6c90dc..a3203c993 100644
--- a/src/ap/ieee802_11_he.c
+++ b/src/ap/ieee802_11_he.c
@@ -520,3 +520,17 @@ int hostapd_get_he_twt_responder(struct hostapd_data *hapd,
 	return !!(mac_cap[HE_MAC_CAPAB_0] & HE_MACCAP_TWT_RESPONDER) &&
 		hapd->iface->conf->he_op.he_twt_responder;
 }
+
+u8 * hostapd_eid_cca(struct hostapd_data *hapd, u8 *eid)
+{
+	if (!hapd->cca_in_progress)
+		return eid;
+
+	*eid++ = WLAN_EID_EXTENSION;
+	*eid++ = 3;
+	*eid++ = WLAN_EID_EXT_COLOR_CHANGE_ANNOUNCEMENT;
+	*eid++ = hapd->cca_count;
+	*eid++ = hapd->cca_color;
+
+	return eid;
+}
diff --git a/src/common/ieee802_11_defs.h b/src/common/ieee802_11_defs.h
index adb89d111..a1112c99b 100644
--- a/src/common/ieee802_11_defs.h
+++ b/src/common/ieee802_11_defs.h
@@ -479,6 +479,7 @@
 #define WLAN_EID_EXT_HE_OPERATION 36
 #define WLAN_EID_EXT_HE_MU_EDCA_PARAMS 38
 #define WLAN_EID_EXT_SPATIAL_REUSE 39
+#define WLAN_EID_EXT_COLOR_CHANGE_ANNOUNCEMENT 42
 #define WLAN_EID_EXT_OCV_OCI 54
 #define WLAN_EID_EXT_SHORT_SSID_LIST 58
 #define WLAN_EID_EXT_HE_6GHZ_BAND_CAP 59
-- 
2.29.2