[nrf noup] Added DNS server refresh after adding new IPv6 address

The Wi-Fi device does not update mDNS queries after obtaining
new IPv6 GUA address, so for some time after assigning prefix,
the Thread Border Routers still use cached link-local address,
which is not routable.

Signed-off-by: Kamil Kasperczyk <kamil.kasperczyk@nordicsemi.no>

src/platform/nrfconnect/wifi/WiFiManager.cpp

@@ -136,12 +136,13 @@ const Map<wifi_iface_state, WiFiManager::StationStatus, 10>
                               { WIFI_STATE_GROUP_HANDSHAKE, WiFiManager::StationStatus::PROVISIONING },
                               { WIFI_STATE_COMPLETED, WiFiManager::StationStatus::FULLY_PROVISIONED } });
 
-const Map<uint32_t, WiFiManager::NetEventHandler, 5>
-    WiFiManager::sEventHandlerMap({ { NET_EVENT_WIFI_SCAN_RESULT, WiFiManager::ScanResultHandler },
-                                    { NET_EVENT_WIFI_SCAN_DONE, WiFiManager::ScanDoneHandler },
-                                    { NET_EVENT_WIFI_CONNECT_RESULT, WiFiManager::ConnectHandler },
-                                    { NET_EVENT_WIFI_DISCONNECT_RESULT, WiFiManager::DisconnectHandler },
-                                    { NET_EVENT_WIFI_DISCONNECT_COMPLETE, WiFiManager::DisconnectHandler } });
+const Map<uint32_t, WiFiManager::NetEventHandler, 5> WiFiManager::sEventHandlerMap({
+    { NET_EVENT_WIFI_SCAN_RESULT, WiFiManager::ScanResultHandler },
+    { NET_EVENT_WIFI_SCAN_DONE, WiFiManager::ScanDoneHandler },
+    { NET_EVENT_WIFI_CONNECT_RESULT, WiFiManager::ConnectHandler },
+    { NET_EVENT_WIFI_DISCONNECT_RESULT, WiFiManager::DisconnectHandler },
+    { NET_EVENT_WIFI_DISCONNECT_COMPLETE, WiFiManager::DisconnectHandler },
+});
 
 void WiFiManager::WifiMgmtEventHandler(net_mgmt_event_callback * cb, uint32_t mgmtEvent, net_if * iface)
 {
@@ -154,14 +155,24 @@ void WiFiManager::WifiMgmtEventHandler(net_mgmt_event_callback * cb, uint32_t mg
     }
 }
 
+void WiFiManager::IPv6MgmtEventHandler(net_mgmt_event_callback * cb, uint32_t mgmtEvent, net_if * iface)
+{
+    if (((mgmtEvent == NET_EVENT_IPV6_ADDR_ADD) || (mgmtEvent == NET_EVENT_IPV6_ADDR_DEL)) && cb->info)
+    {
+        IPv6AddressChangeHandler(cb->info);
+    }
+}
+
 CHIP_ERROR WiFiManager::Init()
 {
     mNetIf = InetUtils::GetWiFiInterface();
     VerifyOrReturnError(mNetIf != nullptr, INET_ERROR_UNKNOWN_INTERFACE);
 
-
     net_mgmt_init_event_callback(&mWiFiMgmtClbk, WifiMgmtEventHandler, kWifiManagementEvents);
+    net_mgmt_init_event_callback(&mIPv6MgmtClbk, IPv6MgmtEventHandler, kIPv6ManagementEvents);
+
     net_mgmt_add_event_callback(&mWiFiMgmtClbk);
+    net_mgmt_add_event_callback(&mIPv6MgmtClbk);
 
     ChipLogDetail(DeviceLayer, "WiFiManager has been initialized");
 
@@ -469,6 +480,25 @@ void WiFiManager::DisconnectHandler(Platform::UniquePtr<uint8_t>)
     });
 }
 
+void WiFiManager::IPv6AddressChangeHandler(const void * data)
+{
+    const in6_addr * addr = reinterpret_cast<const in6_addr *>(data);
+
+    // Filter out link-local addresses that are not routable outside of a local network.
+    if (!net_ipv6_is_ll_addr(addr))
+    {
+        // This is needed to send mDNS queries containing updated IPv6 addresses.
+        ChipDeviceEvent event;
+        event.Type = DeviceEventType::kDnssdRestartNeeded;
+
+        CHIP_ERROR error = PlatformMgr().PostEvent(&event);
+        if (error != CHIP_NO_ERROR)
+        {
+            ChipLogError(DeviceLayer, "Cannot post event: %" CHIP_ERROR_FORMAT, error.Format());
+        }
+    }
+}
+
 WiFiManager::StationStatus WiFiManager::GetStationStatus() const
 {
     return WiFiManager::sStatusMap[mWiFiState];

src/platform/nrfconnect/wifi/WiFiManager.h

@@ -198,14 +198,18 @@ class WiFiManager
     constexpr static uint32_t kWifiManagementEvents = NET_EVENT_WIFI_SCAN_RESULT | NET_EVENT_WIFI_SCAN_DONE |
         NET_EVENT_WIFI_CONNECT_RESULT | NET_EVENT_WIFI_DISCONNECT_RESULT | NET_EVENT_WIFI_IFACE_STATUS;
 
+    constexpr static uint32_t kIPv6ManagementEvents = NET_EVENT_IPV6_ADDR_ADD | NET_EVENT_IPV6_ADDR_DEL;
+
     // Event handling
     static void WifiMgmtEventHandler(net_mgmt_event_callback * cb, uint32_t mgmtEvent, net_if * iface);
+    static void IPv6MgmtEventHandler(net_mgmt_event_callback * cb, uint32_t mgmtEvent, net_if * iface);
     static void ScanResultHandler(Platform::UniquePtr<uint8_t> data);
     static void ScanDoneHandler(Platform::UniquePtr<uint8_t> data);
     static void ConnectHandler(Platform::UniquePtr<uint8_t> data);
     static void DisconnectHandler(Platform::UniquePtr<uint8_t> data);
     static void PostConnectivityStatusChange(ConnectivityChange changeType);
     static void SendRouterSolicitation(System::Layer * layer, void * param);
+    static void IPv6AddressChangeHandler(const void * data);
 
     // Connection Recovery feature
     // This feature allows re-scanning and re-connecting the connection to the known network after
@@ -226,6 +230,7 @@ class WiFiManager
     wifi_iface_state mWiFiState;
     wifi_iface_state mCachedWiFiState;
     net_mgmt_event_callback mWiFiMgmtClbk{};
+    net_mgmt_event_callback mIPv6MgmtClbk{};
     ScanResultCallback mScanResultCallback{ nullptr };
     ScanDoneCallback mScanDoneCallback{ nullptr };
     WiFiNetwork mWantedNetwork{};