feat: add signal strength attributes to BSS struct (#136)

* feat: add signal strength attributes to BSS struct and update tests

* Update wifi.go

Co-authored-by: Ben Kochie <[email protected]>

* fix: update signal strength parsing to use correct types

---------

Co-authored-by: Ben Kochie <[email protected]>

Author: lukas-mbag

client_linux.go

@@ -636,6 +636,12 @@ func (b *BSS) parseAttributes(attrs []netlink.Attribute) error {
 			// NOTE: BSSStatus copies the ordering of nl80211's BSS status
 			// constants.  This may not be the case on other operating systems.
 			b.Status = BSSStatus(nlenc.Uint32(a.Data))
+		case unix.NL80211_BSS_SIGNAL_MBM:
+			// * @NL80211_BSS_SIGNAL_MBM: signal strength in mBm (100*dBm)
+			b.Signal = nlenc.Int32(a.Data)
+		case unix.NL80211_BSS_SIGNAL_UNSPEC:
+			// * @NL80211_BSS_SIGNAL_UNSPEC: signal strength in unspecified units (usually percent)
+			b.SignalUnspecified = nlenc.Uint32(a.Data)
 		case unix.NL80211_BSS_INFORMATION_ELEMENTS:
 			ies, err := parseIEs(a.Data)
 			if err != nil {

client_linux_test.go

@@ -181,12 +181,14 @@ func TestLinux_clientBSSOKSkipMissingStatus(t *testing.T) {
 
 func TestLinux_clientBSSOK(t *testing.T) {
 	want := &BSS{
-		SSID:           "Hello, 世界",
-		BSSID:          net.HardwareAddr{0x00, 0x11, 0x22, 0x33, 0x44, 0x55},
-		Frequency:      2492,
-		BeaconInterval: 100 * 1024 * time.Microsecond,
-		LastSeen:       10 * time.Second,
-		Status:         BSSStatusAssociated,
+		SSID:              "Hello, 世界",
+		BSSID:             net.HardwareAddr{0x00, 0x11, 0x22, 0x33, 0x44, 0x55},
+		Frequency:         2492,
+		BeaconInterval:    100 * 1024 * time.Microsecond,
+		LastSeen:          10 * time.Second,
+		Status:            BSSStatusAssociated,
+		Signal:            -5700,
+		SignalUnspecified: 80,
 	}
 
 	ifi := &Interface{
@@ -471,6 +473,8 @@ func (b *BSS) attributes() []netlink.Attribute {
 				{Type: unix.NL80211_BSS_BEACON_INTERVAL, Data: nlenc.Uint16Bytes(uint16(b.BeaconInterval / 1024 / time.Microsecond))},
 				{Type: unix.NL80211_BSS_SEEN_MS_AGO, Data: nlenc.Uint32Bytes(uint32(b.LastSeen / time.Millisecond))},
 				{Type: unix.NL80211_BSS_STATUS, Data: nlenc.Uint32Bytes(uint32(b.Status))},
+				{Type: unix.NL80211_BSS_SIGNAL_MBM, Data: nlenc.Int32Bytes(int32(b.Signal))},
+				{Type: unix.NL80211_BSS_SIGNAL_UNSPEC, Data: nlenc.Uint32Bytes(uint32(b.SignalUnspecified))},
 				{
 					Type: unix.NL80211_BSS_INFORMATION_ELEMENTS,
 					Data: marshalIEs([]ie{{

wifi.go

@@ -247,6 +247,12 @@ type BSS struct {
 	// Status: The status of the client within the BSS.
 	Status BSSStatus
 
+	// Signal: The signal strength of the BSS, in mBm (divide by 100 to get dBm).
+	Signal int32
+
+	// SignalUnspecified: The signal strength of the BSS, in percent.
+	SignalUnspecified uint32
+
 	// Load: The load element of the BSS (contains StationCount, ChannelUtilization and AvailableAdmissionCapacity).
 	Load BSSLoad