Add more debug prints for 20/40 BSS Coexistence Management frame Rx

This makes it easier to understand what kind of information a STA is
reporting about 20/40 MHz coexistence requirements.

Signed-off-by: Jouni Malinen <jouni@codeaurora.org>

src/ap/ieee802_11.c

@@ -3727,9 +3727,6 @@ static int handle_action(struct hostapd_data *hapd,
 		if (len >= IEEE80211_HDRLEN + 2 &&
 		    mgmt->u.action.u.public_action.action ==
 		    WLAN_PA_20_40_BSS_COEX) {
-			wpa_printf(MSG_DEBUG,
-				   "HT20/40 coex mgmt frame received from STA "
-				   MACSTR, MAC2STR(mgmt->sa));
 			hostapd_2040_coex_action(hapd, mgmt, len);
 			return 1;
 		}

src/ap/ieee802_11_ht.c

@@ -237,16 +237,27 @@ void hostapd_2040_coex_action(struct hostapd_data *hapd,
 	const u8 *start = (const u8 *) mgmt;
 	const u8 *data = start + IEEE80211_HDRLEN + 2;
 
+	wpa_printf(MSG_DEBUG,
+		   "HT: Received 20/40 BSS Coexistence Management frame from "
+		   MACSTR, MAC2STR(mgmt->sa));
+
 	hostapd_logger(hapd, mgmt->sa, HOSTAPD_MODULE_IEEE80211,
 		       HOSTAPD_LEVEL_DEBUG, "hostapd_public_action - action=%d",
 		       mgmt->u.action.u.public_action.action);
 
-	if (!(iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET))
+	if (!(iface->conf->ht_capab & HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET)) {
+		wpa_printf(MSG_DEBUG,
+			   "Ignore 20/40 BSS Coexistence Management frame since 40 MHz capability is not enabled");
 		return;
+	}
 
-	if (len < IEEE80211_HDRLEN + 2 + sizeof(*bc_ie))
+	if (len < IEEE80211_HDRLEN + 2 + sizeof(*bc_ie)) {
+		wpa_printf(MSG_DEBUG,
+			   "Ignore too short 20/40 BSS Coexistence Management frame");
 		return;
+	}
 
+	/* 20/40 BSS Coexistence element */
 	bc_ie = (struct ieee80211_2040_bss_coex_ie *) data;
 	if (bc_ie->element_id != WLAN_EID_20_40_BSS_COEXISTENCE ||
 	    bc_ie->length < 1) {
@@ -254,13 +265,28 @@ void hostapd_2040_coex_action(struct hostapd_data *hapd,
 			   bc_ie->element_id, bc_ie->length);
 		return;
 	}
-	if (len < IEEE80211_HDRLEN + 2 + 2 + bc_ie->length)
+	if (len < IEEE80211_HDRLEN + 2 + 2 + bc_ie->length) {
+		wpa_printf(MSG_DEBUG,
+			   "Truncated 20/40 BSS Coexistence element");
 		return;
+	}
 	data += 2 + bc_ie->length;
 
-	wpa_printf(MSG_DEBUG, "20/40 BSS Coexistence Information field: 0x%x",
-		   bc_ie->coex_param);
+	wpa_printf(MSG_DEBUG,
+		   "20/40 BSS Coexistence Information field: 0x%x (%s%s%s%s%s%s)",
+		   bc_ie->coex_param,
+		   (bc_ie->coex_param & BIT(0)) ? "[InfoReq]" : "",
+		   (bc_ie->coex_param & BIT(1)) ? "[40MHzIntolerant]" : "",
+		   (bc_ie->coex_param & BIT(2)) ? "[20MHzBSSWidthReq]" : "",
+		   (bc_ie->coex_param & BIT(3)) ? "[OBSSScanExemptionReq]" : "",
+		   (bc_ie->coex_param & BIT(4)) ?
+		   "[OBSSScanExemptionGrant]" : "",
+		   (bc_ie->coex_param & (BIT(5) | BIT(6) | BIT(7))) ?
+		   "[Reserved]" : "");
+
 	if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_20MHZ_WIDTH_REQ) {
+		/* Intra-BSS communication prohibiting 20/40 MHz BSS operation
+		 */
 		hostapd_logger(hapd, mgmt->sa,
 			       HOSTAPD_MODULE_IEEE80211,
 			       HOSTAPD_LEVEL_DEBUG,
@@ -269,6 +295,8 @@ void hostapd_2040_coex_action(struct hostapd_data *hapd,
 	}
 
 	if (bc_ie->coex_param & WLAN_20_40_BSS_COEX_40MHZ_INTOL) {
+		/* Inter-BSS communication prohibiting 20/40 MHz BSS operation
+		 */
 		hostapd_logger(hapd, mgmt->sa,
 			       HOSTAPD_MODULE_IEEE80211,
 			       HOSTAPD_LEVEL_DEBUG,
@@ -276,12 +304,16 @@ void hostapd_2040_coex_action(struct hostapd_data *hapd,
 		is_ht40_allowed = 0;
 	}
 
+	/* 20/40 BSS Intolerant Channel Report element (zero or more times) */
 	if (start + len - data >= 3 &&
 	    data[0] == WLAN_EID_20_40_BSS_INTOLERANT && data[1] >= 1) {
 		u8 ielen = data[1];
 
-		if (ielen > start + len - data - 2)
+		if (ielen > start + len - data - 2) {
+			wpa_printf(MSG_DEBUG,
+				   "Truncated 20/40 BSS Intolerant Channel Report element");
 			return;
+		}
 		ic_report = (struct ieee80211_2040_intol_chan_report *) data;
 		wpa_printf(MSG_DEBUG,
 			   "20/40 BSS Intolerant Channel Report: Operating Class %u",