wifi: parse BSS IEs for 80211n and 80211ac data rates

Currently, 'nmcli dev wifi list' does not show the user any rates above
54Mbps.  Now, we can check the IEs passed to NM from the wpa_supplicant,
pull the mcs rate and channel width information, and determine a maximum
possible data rate for 11n and 11ac APs.

https://bugzilla.gnome.org/show_bug.cgi?id=779771

src/devices/wifi/nm-wifi-ap.c

@@ -435,6 +435,339 @@ security_from_vardict (GVariant *security)
 	return flags;
 }
 
+static guint32
+get_max_ht20_rate(int mcs)
+{
+        if (mcs == 0)
+                return 6500000;
+        if (mcs == (1 || 8))
+                return 13000000;
+        if (mcs == (2 || 16))
+                return 19500000;
+        if (mcs == (3 || 9 || 24))
+                return 26000000;
+        if (mcs == (4 || 10 || 17))
+                return 39000000;
+        if (mcs == (5 || 11 || 25))
+                return 52000000;
+        if (mcs == (6 || 18))
+                return 58500000;
+        if (mcs == 7)
+                return 65000000;
+        if (mcs == (12 || 19 || 26))
+                return 78000000;
+        if (mcs == (13 || 27))
+                return 104000000;
+        if (mcs == (14 || 20))
+                return 117000000;
+        if (mcs == 15)
+                return 130000000;
+        if (mcs == (21 || 28))
+                return 156000000;
+        if (mcs == 22)
+                return 175500000;
+        if (mcs == 23)
+                return 195000000;
+        if (mcs == 29)
+                return 208000000;
+        if (mcs == 30)
+                return 234000000;
+	if (mcs == 31)
+		return 260000000;
+
+	return 0;
+}
+
+static guint32
+get_max_ht40_rate(int mcs)
+{
+        if (mcs == 0)
+                return 13500000;
+        if (mcs == (1 || 8))
+                return 27000000;
+        if (mcs == 2)
+                return 40500000;
+        if (mcs == (3 || 9 || 24))
+                return 54000000;
+        if (mcs == (4 || 10 || 17))
+                return 81000000;
+        if (mcs == (5 || 11 || 25))
+                return 108000000;
+        if (mcs == (6 || 18))
+                return 121500000;
+        if (mcs == 7)
+                return 135000000;
+        if (mcs == (12 || 19 || 26))
+                return 162000000;
+        if (mcs == (13  || 27))
+                return 216000000;
+        if (mcs == (14 || 20))
+                return 243000000;
+        if (mcs == 15)
+                return 270000000;
+        if (mcs == 16)
+                return 40500000;
+        if (mcs == (21 || 28))
+                return 324000000;
+        if (mcs == 22)
+                return 364500000;
+        if (mcs == 23)
+                return 405000000;
+        if (mcs == 29)
+                return 432000000;
+        if (mcs == 30)
+                return 486000000;
+        if (mcs == 31)
+	        return 540000000;
+
+	return 0;
+}
+
+static guint32
+get_max_vht80_rate_ss1(int mcs)
+{
+        if (mcs == 0)
+                return 29300000;
+        if (mcs == 1)
+                return 58500000;
+        if (mcs == 2)
+                return 87800000;
+        if (mcs == 3)
+                return 117000000;
+        if (mcs == 4)
+                return 175500000;
+        if (mcs == 5)
+                return 234000000;
+        if (mcs == 6)
+                return 263300000;
+        if (mcs == 7)
+                return 292500000;
+        if (mcs == 8)
+                return 351000000;
+	 if (mcs == 9)
+		return 390000000;
+	 return 0;
+}
+
+static guint32
+get_max_vht80_rate_ss2(int mcs)
+{
+
+	if (mcs == 0)
+		return 58500000;
+	if (mcs == 1)
+		return 117000000;
+	if (mcs == 2)
+		return 175500000;
+	if (mcs == 3)
+		return 234000000;
+	if (mcs == 4)
+		return 351000000;
+	if (mcs == 5)
+		return 468000000;
+	if (mcs == 6)
+		return 526500000;
+	if (mcs == 7)
+		return 585000000;
+	if (mcs == 8)
+		return 702000000;
+	if (mcs == 9)
+		return 780000000;
+	return 0;
+}
+
+static guint32
+get_max_vht80_rate_ss3(int mcs)
+{
+
+	if (mcs == 0)
+		return 87800000;
+	if (mcs == 1)
+		return 175500000;
+	if (mcs == 2)
+		return 263300000;
+	if (mcs == 3)
+		return 351000000;
+	if (mcs == 4)
+		return 526500000;
+	if (mcs == 5)
+		return 702000000;
+	if (mcs == 6)
+		return 0;
+	if (mcs == 7)
+		return 877500000;
+	if (mcs == 8)
+		return 105300000;
+	if (mcs == 9)
+		return 117000000;
+	return 0;
+}
+
+static guint32
+get_max_vht160_rate_ss1(int mcs)
+{
+	if (mcs == 0)
+                return 58500000;
+	if (mcs == 1)
+                return 117000000;
+	if (mcs == 2)
+                return 175500000;
+	if (mcs == 3)
+                return 234000000;
+	if (mcs == 4)
+                return 351000000;
+	if (mcs == 5)
+                return 468000000;
+	if (mcs == 6)
+                return 526500000;
+	if (mcs == 7)
+                return 585000000;
+	if (mcs == 8)
+                return 702000000;
+	if (mcs == 9)
+		return 780000000;
+	return 0;
+}
+
+static guint32
+get_max_vht160_rate_ss2(int mcs)
+{
+
+	if (mcs == 0)
+		return 117000000;
+	if (mcs == 1)
+		return 234000000;
+	if (mcs == 2)
+		return 351000000;
+	if (mcs == 3)
+		return 468000000;
+	if (mcs == 4)
+		return 702000000;
+	if (mcs == 5)
+		return 936000000;
+	if (mcs == 6)
+		return 1053000000;
+	if (mcs == 7)
+		return 1170000000;
+	if (mcs == 8)
+		return 1404000000;
+	if (mcs == 9)
+		return 1560000000;
+	return 0;
+}
+
+static guint32
+get_max_vht160_rate_ss3(int mcs)
+{
+
+	if (mcs == 0)
+		return 175500000;
+	if (mcs == 1)
+		return 351000000;
+	if (mcs == 2)
+		return 526500000;
+	if (mcs == 3)
+		return 702000000;
+	if (mcs == 4)
+		return 1053000000;
+	if (mcs == 5)
+		return 1404000000;
+	if (mcs == 6)
+		return 1579500000;
+	if (mcs == 7)
+		return 1755000000;
+	if (mcs == 8)
+		return 2106000000;
+	if (mcs == 9)
+		return 0;
+	return 0;
+}
+
+static guint32
+get_max_ht_rate(guint16 ht_cap_info, const guint8 * supported_mcs_set){
+	guint32 mcs,i,j;
+
+	/* Find the maximum supported mcs rate */
+	mcs = -1;
+	for (i = 0; i <= 15; i++){
+		for (j = 0; j <= 7; j++){
+			if (*supported_mcs_set & (1 << j))
+				mcs++;
+		}
+		supported_mcs_set++;
+	}
+
+	/* Check for 40Mhz wide channel support */
+	if (ht_cap_info & (1 << 1))
+		return get_max_ht40_rate(mcs);
+	else
+		return get_max_ht20_rate(mcs);
+
+}
+
+static guint32
+get_max_vht_rate(guint32 vht_cap,guint16 tx_map){
+	guint32 mcs = 7, ss = 1;
+
+	/* Check for mcs rates 8 and 9 support */
+	if (tx_map & 0x2a)
+		mcs = 9;
+	else if (tx_map & 0x15)
+		mcs = 8;
+
+	/* Check for 160Mhz wide channel support and
+	 * spatial stream support */
+	if ( vht_cap & (1 << 2)){
+		if (tx_map & 0x30)
+			return get_max_vht160_rate_ss3(mcs);
+		else if (tx_map & 0x0C)
+			return get_max_vht160_rate_ss2(mcs);
+		else
+			return get_max_vht160_rate_ss1(mcs);
+	} else {
+		if (tx_map & 0x30)
+			return get_max_vht80_rate_ss3(mcs);
+		else if (tx_map & 0x0C)
+			return get_max_vht80_rate_ss2(mcs);
+		else
+			return get_max_vht80_rate_ss1(mcs);
+	}
+
+	return 0;
+}
+
+#define IEEE_80211_IE_HT_CAP	45
+#define IEEE_80211_IE_VHT_CAP   191
+
+static guint32
+get_max_rate(const guint8 *bytes, gsize len){
+	guint8 id, elem_len;
+	guint32 max_rate = 0;
+
+	while (len >= 2) {
+		id = *bytes++;
+		elem_len = *bytes++;
+		len -= 2;
+
+		if (elem_len > len) {
+			return -1;
+		}
+
+		if (id == IEEE_80211_IE_HT_CAP){
+			max_rate = get_max_ht_rate(*bytes,bytes+3);
+		}
+
+		if (id == IEEE_80211_IE_VHT_CAP) {
+			max_rate = get_max_vht_rate(*bytes,*(bytes+8));
+		}
+
+		len -= elem_len;
+		bytes += elem_len;
+	}
+
+	return max_rate;
+}
+
 gboolean
 nm_wifi_ap_update_from_properties (NMWifiAP *ap,
                                    const char *supplicant_path,
@@ -513,6 +846,15 @@ nm_wifi_ap_update_from_properties (NMWifiAP *ap,
 		g_variant_unref (v);
 	}
 
+	v = g_variant_lookup_value (properties, "IEs", G_VARIANT_TYPE_BYTESTRING);
+	if (v){
+		bytes = g_variant_get_fixed_array (v, &len, 1);
+		guint32 max_rate = get_max_rate(bytes,len);
+		if (max_rate > 0)
+			nm_wifi_ap_set_max_bitrate (ap, max_rate / 1000);
+		g_variant_unref(v);
+	}
+
 	v = g_variant_lookup_value (properties, "WPA", G_VARIANT_TYPE_VARDICT);
 	if (v) {
 		changed |= nm_wifi_ap_set_wpa_flags (ap, priv->wpa_flags | security_from_vardict (v));