From fe48a4b35cf6373ba033134944da10aa51d1d85a Mon Sep 17 00:00:00 2001
From: Fernando Fernandez Mancera <ffmancera@riseup.net>
Date: Thu, 27 Jul 2023 16:15:47 +0200
Subject: [PATCH] wifi: parse access point announced bandwidth

Parse the access point announced bandwidth in MHz. This is considering
both HT and VHT. Please notice that for VHT 80+80 MHz we are representing it
as 160 MHz.
---
 ...freedesktop.NetworkManager.AccessPoint.xml |  7 ++
 src/core/devices/wifi/nm-wifi-ap.c            | 41 +++++++++
 src/core/devices/wifi/nm-wifi-ap.h            |  3 +
 src/core/nm-core-utils.c                      | 85 +++++++++++++++++++
 src/core/nm-core-utils.h                      |  1 +
 src/core/supplicant/nm-supplicant-interface.c | 11 ++-
 src/core/supplicant/nm-supplicant-types.h     |  2 +
 src/libnm-client-impl/libnm.ver               |  5 ++
 src/libnm-client-impl/nm-access-point.c       | 39 +++++++++
 src/libnm-client-public/nm-access-point.h     |  4 +
 10 files changed, 196 insertions(+), 2 deletions(-)

diff --git a/introspection/org.freedesktop.NetworkManager.AccessPoint.xml b/introspection/org.freedesktop.NetworkManager.AccessPoint.xml
index 7340bda308..287bfaa9a4 100644
--- a/introspection/org.freedesktop.NetworkManager.AccessPoint.xml
+++ b/introspection/org.freedesktop.NetworkManager.AccessPoint.xml
@@ -79,6 +79,13 @@
     -->
     <property name="MaxBitrate" type="u" access="read"/>
 
+    <!--
+        Bandwidth:
+
+        The bandwidth announced by the access point in MHz.
+    -->
+    <property name="Bandwidth" type="u" access="read"/>
+
     <!--
         Strength:
 
diff --git a/src/core/devices/wifi/nm-wifi-ap.c b/src/core/devices/wifi/nm-wifi-ap.c
index 825a5aa8f1..d4d3815e7a 100644
--- a/src/core/devices/wifi/nm-wifi-ap.c
+++ b/src/core/devices/wifi/nm-wifi-ap.c
@@ -36,6 +36,7 @@ NM_GOBJECT_PROPERTIES_DEFINE(NMWifiAP,
                              PROP_HW_ADDRESS,
                              PROP_MODE,
                              PROP_MAX_BITRATE,
+                             PROP_BANDWIDTH,
                              PROP_STRENGTH,
                              PROP_LAST_SEEN, );
 
@@ -47,6 +48,7 @@ struct _NMWifiAPPrivate {
     guint8       strength;
     guint32      freq;        /* Frequency in MHz; ie 2412 (== 2.412 GHz) */
     guint32      max_bitrate; /* Maximum bitrate of the AP in Kbit/s (ie 54000 Kb/s == 54Mbit/s) */
+    guint32      bandwidth;   /* Bandwidth of the AP in MHz */
 
     gint64
         last_seen_msec; /* Timestamp when the AP was seen lastly (in nm_utils_get_monotonic_timestamp_*() scale).
@@ -277,6 +279,32 @@ nm_wifi_ap_get_max_bitrate(NMWifiAP *ap)
     return NM_WIFI_AP_GET_PRIVATE(ap)->max_bitrate;
 }
 
+guint32
+nm_wifi_ap_get_bandwidth(NMWifiAP *ap)
+{
+    g_return_val_if_fail(NM_IS_WIFI_AP(ap), 0);
+    g_return_val_if_fail(nm_dbus_object_is_exported(NM_DBUS_OBJECT(ap)), 0);
+
+    return NM_WIFI_AP_GET_PRIVATE(ap)->bandwidth;
+}
+
+gboolean
+nm_wifi_ap_set_bandwidth(NMWifiAP *ap, guint32 bandwidth)
+{
+    NMWifiAPPrivate *priv;
+
+    g_return_val_if_fail(NM_IS_WIFI_AP(ap), FALSE);
+
+    priv = NM_WIFI_AP_GET_PRIVATE(ap);
+
+    if (priv->bandwidth != bandwidth) {
+        priv->bandwidth = bandwidth;
+        _notify(ap, PROP_BANDWIDTH);
+        return TRUE;
+    }
+    return FALSE;
+}
+
 gboolean
 nm_wifi_ap_set_max_bitrate(NMWifiAP *ap, guint32 bitrate)
 {
@@ -393,6 +421,7 @@ nm_wifi_ap_update_from_properties(NMWifiAP *ap, const NMSupplicantBssInfo *bss_i
     }
 
     changed |= nm_wifi_ap_set_max_bitrate(ap, bss_info->max_rate);
+    changed |= nm_wifi_ap_set_bandwidth(ap, bss_info->bandwidth);
 
     if (priv->metered != bss_info->metered) {
         priv->metered = bss_info->metered;
@@ -683,6 +712,9 @@ get_property(GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
     case PROP_MAX_BITRATE:
         g_value_set_uint(value, priv->max_bitrate);
         break;
+    case PROP_BANDWIDTH:
+        g_value_set_uint(value, priv->bandwidth);
+        break;
     case PROP_STRENGTH:
         g_value_set_uchar(value, priv->strength);
         break;
@@ -873,6 +905,7 @@ static const NMDBusInterfaceInfoExtended interface_info_access_point = {
             NM_DEFINE_DBUS_PROPERTY_INFO_EXTENDED_READABLE("MaxBitrate",
                                                            "u",
                                                            NM_WIFI_AP_MAX_BITRATE),
+            NM_DEFINE_DBUS_PROPERTY_INFO_EXTENDED_READABLE("Bandwidth", "u", NM_WIFI_AP_BANDWIDTH),
             NM_DEFINE_DBUS_PROPERTY_INFO_EXTENDED_READABLE("Strength", "y", NM_WIFI_AP_STRENGTH),
             NM_DEFINE_DBUS_PROPERTY_INFO_EXTENDED_READABLE("LastSeen",
                                                            "i",
@@ -979,6 +1012,14 @@ nm_wifi_ap_class_init(NMWifiAPClass *ap_class)
                                                       -1,
                                                       G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
 
+    obj_properties[PROP_BANDWIDTH] = g_param_spec_uint(NM_WIFI_AP_BANDWIDTH,
+                                                       "",
+                                                       "",
+                                                       0,
+                                                       G_MAXUINT32,
+                                                       0,
+                                                       G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
+
     g_object_class_install_properties(object_class, _PROPERTY_ENUMS_LAST, obj_properties);
 }
 
diff --git a/src/core/devices/wifi/nm-wifi-ap.h b/src/core/devices/wifi/nm-wifi-ap.h
index 93dc8edf3e..0f229640b5 100644
--- a/src/core/devices/wifi/nm-wifi-ap.h
+++ b/src/core/devices/wifi/nm-wifi-ap.h
@@ -27,6 +27,7 @@
 #define NM_WIFI_AP_HW_ADDRESS  "hw-address"
 #define NM_WIFI_AP_MODE        "mode"
 #define NM_WIFI_AP_MAX_BITRATE "max-bitrate"
+#define NM_WIFI_AP_BANDWIDTH   "bandwidth"
 #define NM_WIFI_AP_STRENGTH    "strength"
 #define NM_WIFI_AP_LAST_SEEN   "last-seen"
 
@@ -78,6 +79,8 @@ guint32                nm_wifi_ap_get_freq(NMWifiAP *ap);
 gboolean               nm_wifi_ap_set_freq(NMWifiAP *ap, guint32 freq);
 guint32                nm_wifi_ap_get_max_bitrate(NMWifiAP *ap);
 gboolean               nm_wifi_ap_set_max_bitrate(NMWifiAP *ap, guint32 bitrate);
+guint32                nm_wifi_ap_get_bandwidth(NMWifiAP *ap);
+gboolean               nm_wifi_ap_set_bandwidth(NMWifiAP *ap, guint32 bandwidth);
 gboolean               nm_wifi_ap_get_fake(const NMWifiAP *ap);
 gboolean               nm_wifi_ap_set_fake(NMWifiAP *ap, gboolean fake);
 NM80211ApFlags         nm_wifi_ap_get_flags(const NMWifiAP *self);
diff --git a/src/core/nm-core-utils.c b/src/core/nm-core-utils.c
index 5442efbf88..822f138055 100644
--- a/src/core/nm-core-utils.c
+++ b/src/core/nm-core-utils.c
@@ -4779,15 +4779,91 @@ get_max_rate_vht(const guint8 *bytes, guint len, guint32 *out_maxrate)
     return TRUE;
 }
 
+static gboolean
+get_bandwidth_ht(const guint8 *bytes, guint len, guint32 *out_bandwidth)
+{
+    guint8 ht_op_flag_group;
+
+    /* http://standards.ieee.org/getieee802/download/802.11-2012.pdf
+     * https://mrncciew.com/2014/11/04/cwap-ht-operations-ie/
+     * IEEE std 802.11-2020 section 9.4.2.56
+     */
+
+    if (len != 22)
+        return FALSE;
+
+    ht_op_flag_group = bytes[1];
+
+    /* Check bit for 20Mhz or 40Mhz */
+    if (ht_op_flag_group & (1 << 2))
+        *out_bandwidth = 40;
+    else
+        *out_bandwidth = 20;
+
+    return TRUE;
+}
+
+static gboolean
+get_bandwidth_vht(const guint8 *bytes, guint len, guint32 *out_bandwidth)
+{
+    guint8 sta_channel_width;
+    guint8 ccfs0;
+    guint8 ccfs1;
+
+    /* http://chimera.labs.oreilly.com/books/1234000001739/ch03.html#management_frames
+     * https://community.arubanetworks.com/community-home/librarydocuments/viewdocument?DocumentKey=799aad1b-d9c4-421a-a492-a111e8680d34&CommunityKey=39a6bdf4-2376-46f9-853a-49420d2d0caa&tab=librarydocuments
+     * IEEE Std 802.11-2020 section 9.4.2.158
+     */
+
+    if (len < 3)
+        return FALSE;
+
+    sta_channel_width = bytes[0];
+    ccfs0             = bytes[1];
+    ccfs1             = bytes[2];
+    switch (sta_channel_width) {
+    case 0:
+        /* we rely on HT Operation IE value*/
+        return FALSE;
+    case 1:
+        if (ccfs1 == 0)
+            *out_bandwidth = 80;
+        else if (abs(ccfs1 - ccfs0) == 8)
+            *out_bandwidth = 160;
+        else if (abs(ccfs1 - ccfs0) > 16)
+            /* we are considering 80+80 as 160 */
+            *out_bandwidth = 160;
+        else
+            /* falling back to 80 MHz */
+            *out_bandwidth = 80;
+        break;
+    case 2:
+        /* deprecated */
+        *out_bandwidth = 160;
+        break;
+    case 3:
+        /* deprecated */
+        *out_bandwidth = 160;
+        break;
+    default:
+        return FALSE;
+    }
+
+    return TRUE;
+}
+
 /* Management Frame Information Element IDs, ieee80211_eid */
 #define WLAN_EID_HT_CAPABILITY   45
+#define WLAN_EID_HT_OPERATION    61
 #define WLAN_EID_VHT_CAPABILITY  191
+#define WLAN_EID_VHT_OPERATION   192
 #define WLAN_EID_VENDOR_SPECIFIC 221
 
 void
 nm_wifi_utils_parse_ies(const guint8 *bytes,
                         gsize         len,
                         guint32      *out_max_rate,
+                        guint32      *out_bandwidth,
                         gboolean     *out_metered,
                         gboolean     *out_owe_transition_mode)
 {
@@ -4795,6 +4871,7 @@ nm_wifi_utils_parse_ies(const guint8 *bytes,
     guint32 m;
 
     NM_SET_OUT(out_max_rate, 0);
+    NM_SET_OUT(out_bandwidth, 0);
     NM_SET_OUT(out_metered, FALSE);
     NM_SET_OUT(out_owe_transition_mode, FALSE);
 
@@ -4816,12 +4893,20 @@ nm_wifi_utils_parse_ies(const guint8 *bytes,
                     *out_max_rate = NM_MAX(*out_max_rate, m);
             }
             break;
+        case WLAN_EID_HT_OPERATION:
+            if (out_bandwidth)
+                get_bandwidth_ht(bytes, elem_len, out_bandwidth);
+            break;
         case WLAN_EID_VHT_CAPABILITY:
             if (out_max_rate) {
                 if (get_max_rate_vht(bytes, elem_len, &m))
                     *out_max_rate = NM_MAX(*out_max_rate, m);
             }
             break;
+        case WLAN_EID_VHT_OPERATION:
+            if (out_bandwidth)
+                get_bandwidth_vht(bytes, elem_len, out_bandwidth);
+            break;
         case WLAN_EID_VENDOR_SPECIFIC:
             if (len == 8 && bytes[0] == 0x00 /* OUI: Microsoft */
                 && bytes[1] == 0x50 && bytes[2] == 0xf2
diff --git a/src/core/nm-core-utils.h b/src/core/nm-core-utils.h
index 5511250422..d73cfd6467 100644
--- a/src/core/nm-core-utils.h
+++ b/src/core/nm-core-utils.h
@@ -455,6 +455,7 @@ const char *nm_utils_parse_dns_domain(const char *domain, gboolean *is_routing);
 void nm_wifi_utils_parse_ies(const guint8 *bytes,
                              gsize         len,
                              guint32      *out_max_rate,
+                             guint32      *out_bandwidth,
                              gboolean     *out_metered,
                              gboolean     *out_owe_transition_mode);
 
diff --git a/src/core/supplicant/nm-supplicant-interface.c b/src/core/supplicant/nm-supplicant-interface.c
index 18525724f4..e7bdfd49df 100644
--- a/src/core/supplicant/nm-supplicant-interface.c
+++ b/src/core/supplicant/nm-supplicant-interface.c
@@ -765,9 +765,15 @@ _bss_info_properties_changed(NMSupplicantInterface *self,
         gboolean p_owe_transition_mode;
         gboolean p_metered;
         guint32  rate;
+        guint32  bandwidth;
 
         arr_data = g_variant_get_fixed_array(v_v, &arr_len, 1);
-        nm_wifi_utils_parse_ies(arr_data, arr_len, &rate, &p_metered, &p_owe_transition_mode);
+        nm_wifi_utils_parse_ies(arr_data,
+                                arr_len,
+                                &rate,
+                                &bandwidth,
+                                &p_metered,
+                                &p_owe_transition_mode);
         p_max_rate     = NM_MAX(p_max_rate, rate);
         p_max_rate_has = TRUE;
         g_variant_unref(v_v);
@@ -777,7 +783,8 @@ _bss_info_properties_changed(NMSupplicantInterface *self,
         else
             bss_info->rsn_flags &= ~NM_802_11_AP_SEC_KEY_MGMT_OWE_TM;
 
-        bss_info->metered = p_metered;
+        bss_info->metered   = p_metered;
+        bss_info->bandwidth = bandwidth;
     }
 
     if (p_max_rate_has)
diff --git a/src/core/supplicant/nm-supplicant-types.h b/src/core/supplicant/nm-supplicant-types.h
index 1ae67e1382..1f04c12b82 100644
--- a/src/core/supplicant/nm-supplicant-types.h
+++ b/src/core/supplicant/nm-supplicant-types.h
@@ -179,6 +179,8 @@ typedef struct _NMSupplicantBssInfo {
 
     guint32 max_rate;
 
+    guint32 bandwidth;
+
     guint8 signal_percent;
 
     NMEtherAddr bssid;
diff --git a/src/libnm-client-impl/libnm.ver b/src/libnm-client-impl/libnm.ver
index 919ffc74b8..acbfb4a6e6 100644
--- a/src/libnm-client-impl/libnm.ver
+++ b/src/libnm-client-impl/libnm.ver
@@ -1943,3 +1943,8 @@ global:
 	nm_setting_link_get_type;
 	nm_setting_link_new;
 } libnm_1_42_0;
+
+libnm_1_46_0 {
+global:
+	nm_access_point_get_bandwidth;
+} libnm_1_44_0;
diff --git a/src/libnm-client-impl/nm-access-point.c b/src/libnm-client-impl/nm-access-point.c
index 94b38f0300..a06bee4846 100644
--- a/src/libnm-client-impl/nm-access-point.c
+++ b/src/libnm-client-impl/nm-access-point.c
@@ -30,6 +30,7 @@ NM_GOBJECT_PROPERTIES_DEFINE(NMAccessPoint,
                              PROP_HW_ADDRESS,
                              PROP_MODE,
                              PROP_MAX_BITRATE,
+                             PROP_BANDWIDTH,
                              PROP_STRENGTH,
                              PROP_BSSID,
                              PROP_LAST_SEEN, );
@@ -43,6 +44,7 @@ typedef struct {
     guint32 frequency;
     guint32 mode;
     guint32 max_bitrate;
+    guint32 bandwidth;
     gint32  last_seen;
     guint8  strength;
 } NMAccessPointPrivate;
@@ -198,6 +200,24 @@ nm_access_point_get_max_bitrate(NMAccessPoint *ap)
     return NM_ACCESS_POINT_GET_PRIVATE(ap)->max_bitrate;
 }
 
+/**
+ * nm_access_point_get_bandwidth:
+ * @ap: a #NMAccessPoint
+ *
+ * Gets the bandwidth advertised by the access point in MHz.
+ *
+ * Returns: the advertised bandwidth (MHz)
+ *
+ * Since: 1.46
+ **/
+guint32
+nm_access_point_get_bandwidth(NMAccessPoint *ap)
+{
+    g_return_val_if_fail(NM_IS_ACCESS_POINT(ap), 0);
+
+    return NM_ACCESS_POINT_GET_PRIVATE(ap)->bandwidth;
+}
+
 /**
  * nm_access_point_get_strength:
  * @ap: a #NMAccessPoint
@@ -463,6 +483,9 @@ get_property(GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
     case PROP_MAX_BITRATE:
         g_value_set_uint(value, nm_access_point_get_max_bitrate(ap));
         break;
+    case PROP_BANDWIDTH:
+        g_value_set_uint(value, nm_access_point_get_bandwidth(ap));
+        break;
     case PROP_STRENGTH:
         g_value_set_uchar(value, nm_access_point_get_strength(ap));
         break;
@@ -480,6 +503,7 @@ const NMLDBusMetaIface _nml_dbus_meta_iface_nm_accesspoint = NML_DBUS_META_IFACE
     nm_access_point_get_type,
     NML_DBUS_META_INTERFACE_PRIO_INSTANTIATE_30,
     NML_DBUS_META_IFACE_DBUS_PROPERTIES(
+        NML_DBUS_META_PROPERTY_INIT_U("Bandwidth", PROP_BANDWIDTH, NMAccessPoint, _priv.bandwidth),
         NML_DBUS_META_PROPERTY_INIT_U("Flags", PROP_FLAGS, NMAccessPoint, _priv.flags),
         NML_DBUS_META_PROPERTY_INIT_U("Frequency", PROP_FREQUENCY, NMAccessPoint, _priv.frequency),
         NML_DBUS_META_PROPERTY_INIT_FCN("HwAddress",
@@ -620,6 +644,21 @@ nm_access_point_class_init(NMAccessPointClass *ap_class)
                                                          0,
                                                          G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
 
+    /**
+     * NMAccessPoint:bandwidth:
+     *
+     * The channel bandwidth announced by the AP in MHz.
+     *
+     * Since: 1.46
+     **/
+    obj_properties[PROP_BANDWIDTH] = g_param_spec_uint(NM_ACCESS_POINT_BANDWIDTH,
+                                                       "",
+                                                       "",
+                                                       0,
+                                                       G_MAXUINT32,
+                                                       0,
+                                                       G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
+
     /**
      * NMAccessPoint:strength:
      *
diff --git a/src/libnm-client-public/nm-access-point.h b/src/libnm-client-public/nm-access-point.h
index 5a78e34f73..f2cc1a4cc5 100644
--- a/src/libnm-client-public/nm-access-point.h
+++ b/src/libnm-client-public/nm-access-point.h
@@ -35,6 +35,7 @@ G_BEGIN_DECLS
 #define NM_ACCESS_POINT_MAX_BITRATE "max-bitrate"
 #define NM_ACCESS_POINT_STRENGTH    "strength"
 #define NM_ACCESS_POINT_LAST_SEEN   "last-seen"
+#define NM_ACCESS_POINT_BANDWIDTH   "bandwidth"
 
 /* DEPRECATED */
 #define NM_ACCESS_POINT_HW_ADDRESS "hw-address"
@@ -59,6 +60,9 @@ guint8                 nm_access_point_get_strength(NMAccessPoint *ap);
 NM_AVAILABLE_IN_1_2
 int nm_access_point_get_last_seen(NMAccessPoint *ap);
 
+NM_AVAILABLE_IN_1_46
+guint32 nm_access_point_get_bandwidth(NMAccessPoint *ap);
+
 GPtrArray *nm_access_point_filter_connections(NMAccessPoint *ap, const GPtrArray *connections);
 
 gboolean nm_access_point_connection_valid(NMAccessPoint *ap, NMConnection *connection);