EHT: Validate puncturing bitmap

Validate preamble puncturing bitmap.

Signed-off-by: Aloka Dixit <quic_alokad@quicinc.com>

3 files changed, 120 insertions, 0 deletions

diff --git a/src/ap/hw_features.c b/src/ap/hw_features.c
index ed5ff41d3..842d9f5ba 100644
--- a/src/ap/hw_features.c
+++ b/src/ap/hw_features.c
@@ -893,6 +893,55 @@ static int hostapd_is_usable_edmg(struct hostapd_iface *iface)
 }
 
 
+static bool hostapd_is_usable_punct_bitmap(struct hostapd_iface *iface)
+{
+#ifdef CONFIG_IEEE80211BE
+	struct hostapd_config *conf = iface->conf;
+	u8 bw, start_chan;
+
+	if (!conf->punct_bitmap)
+		return true;
+
+	if (!conf->ieee80211be) {
+		wpa_printf(MSG_ERROR,
+			   "Currently RU puncturing is supported only if ieee80211be is enabled");
+		return false;
+	}
+
+	if (iface->freq >= 2412 && iface->freq <= 2484) {
+		wpa_printf(MSG_ERROR,
+			   "RU puncturing not supported in 2.4 GHz");
+		return false;
+	}
+
+	switch (conf->eht_oper_chwidth) {
+	case 0:
+		wpa_printf(MSG_ERROR,
+			   "RU puncturing is supported only in 80 MHz and 160 MHz");
+		return false;
+	case 1:
+		bw = 80;
+		start_chan = conf->eht_oper_centr_freq_seg0_idx - 6;
+		break;
+	case 2:
+		bw = 160;
+		start_chan = conf->eht_oper_centr_freq_seg0_idx - 14;
+		break;
+	default:
+		return false;
+	}
+
+	if (!is_punct_bitmap_valid(bw, (conf->channel - start_chan) / 4,
+				   conf->punct_bitmap)) {
+		wpa_printf(MSG_ERROR, "Invalid puncturing bitmap");
+		return false;
+	}
+#endif /* CONFIG_IEEE80211BE */
+
+	return true;
+}
+
+
 static int hostapd_is_usable_chans(struct hostapd_iface *iface)
 {
 	int secondary_freq;
@@ -915,6 +964,9 @@ static int hostapd_is_usable_chans(struct hostapd_iface *iface)
 	if (!hostapd_is_usable_edmg(iface))
 		return 0;
 
+	if (!hostapd_is_usable_punct_bitmap(iface))
+		return 0;
+
 	if (!iface->conf->secondary_channel)
 		return 1;
 
diff --git a/src/common/hw_features_common.c b/src/common/hw_features_common.c
index 6646301df..584c6d275 100644
--- a/src/common/hw_features_common.c
+++ b/src/common/hw_features_common.c
@@ -876,3 +876,70 @@ int chan_pri_allowed(const struct hostapd_channel_data *chan)
 	return !(chan->flag & HOSTAPD_CHAN_DISABLED) &&
 		(chan->allowed_bw & HOSTAPD_CHAN_WIDTH_20);
 }
+
+
+/* IEEE P802.11be/D3.0, Table 36-30 - Definition of the Punctured Channel
+ * Information field in the U-SIG for an EHT MU PPDU using non-OFDMA
+ * transmissions */
+static const u16 punct_bitmap_80[] = { 0xF, 0xE, 0xD, 0xB, 0x7 };
+static const u16 punct_bitmap_160[] = {
+	0xFF, 0xFE, 0xFD, 0xFB, 0xF7, 0xEF, 0xDF, 0xBF,
+	0x7F, 0xFC, 0xF3, 0xCF, 0x3F
+};
+static const u16 punct_bitmap_320[] = {
+	0xFFFF, 0xFFFC, 0xFFF3, 0xFFCF, 0xFF3F, 0xFCFF, 0xF3FF, 0xCFFF,
+	0x3FFF, 0xFFF0, 0xFF0F, 0xF0FF, 0x0FFF, 0xFFC0, 0xFF30, 0xFCF0,
+	0xF3F0, 0xCFF0, 0x3FF0, 0x0FFC, 0x0FF3, 0x0FCF, 0x0F3F, 0x0CFF,
+	0x03FF
+};
+
+
+bool is_punct_bitmap_valid(u16 bw, u16 pri_ch_bit_pos, u16 punct_bitmap)
+{
+	u8 i, count;
+	u16 bitmap;
+	const u16 *valid_bitmaps;
+
+	if (!punct_bitmap) /* All channels active */
+		return true;
+
+	bitmap = ~punct_bitmap;
+
+	switch (bw) {
+	case 80:
+		bitmap &= 0xF;
+		valid_bitmaps = punct_bitmap_80;
+		count = ARRAY_SIZE(punct_bitmap_80);
+		break;
+
+	case 160:
+		bitmap &= 0xFF;
+		valid_bitmaps = punct_bitmap_160;
+		count = ARRAY_SIZE(punct_bitmap_160);
+		break;
+
+	case 320:
+		bitmap &= 0xFFFF;
+		valid_bitmaps = punct_bitmap_320;
+		count = ARRAY_SIZE(punct_bitmap_320);
+		break;
+
+	default:
+		return false;
+	}
+
+	if (!bitmap) /* No channel active */
+		return false;
+
+	if (!(bitmap & BIT(pri_ch_bit_pos))) {
+		wpa_printf(MSG_DEBUG, "Primary channel cannot be punctured");
+		return false;
+	}
+
+	for (i = 0; i < count; i++) {
+		if (valid_bitmaps[i] == bitmap)
+			return true;
+	}
+
+	return false;
+}
diff --git a/src/common/hw_features_common.h b/src/common/hw_features_common.h
index d8ca16867..82e028238 100644
--- a/src/common/hw_features_common.h
+++ b/src/common/hw_features_common.h
@@ -54,5 +54,6 @@ u32 num_chan_to_bw(int num_chans);
 int chan_bw_allowed(const struct hostapd_channel_data *chan, u32 bw,
 		    int ht40_plus, int pri);
 int chan_pri_allowed(const struct hostapd_channel_data *chan);
+bool is_punct_bitmap_valid(u16 bw, u16 pri_ch_bit_pos, u16 punct_bitmap);
 
 #endif /* HW_FEATURES_COMMON_H */