NetworkDiscovery: Fix localhost lookup and prevent usage of IPv6 on host lookup

libnymea-core/hardware/network/networkdevicediscoveryimpl.cpp

@@ -274,6 +274,10 @@ NetworkDeviceMonitor *NetworkDeviceDiscoveryImpl::registerMonitor(Thing *thing)
         connect(reply, &NetworkDeviceDiscoveryReply::finished, reply, &NetworkDeviceDiscoveryReply::deleteLater);
     }
 
+    if (address == QHostAddress::LocalHost || hostName == "localhost") {
+        // Special case, we create for localhost a networkdevice info, since we are not discovering localhost
+        internalMonitor->setNetworkDeviceInfo(NetworkDeviceInfo(QHostAddress("127.0.0.1")));
+    } else {
         // Find and set the network device info
         for (int i = 0; i < m_networkInfoCache.count(); i++) {
             const NetworkDeviceInfo networkDeviceInfo = m_networkInfoCache.at(i);
@@ -302,6 +306,7 @@ NetworkDeviceMonitor *NetworkDeviceDiscoveryImpl::registerMonitor(Thing *thing)
                 break;
             }
         }
+    }
 
     // Create a new plugin monitor object we are going to return...
     NetworkDeviceMonitorImpl *pluginMonitor = createPluginMonitor(internalMonitor);
@@ -609,6 +614,11 @@ void NetworkDeviceDiscoveryImpl::loadNetworkDeviceCache()
 
     qCInfo(dcNetworkDeviceDiscovery()) << "Loaded" << m_networkInfoCache.count() << "network device infos from cache.";
 
+    // Add the localhost
+    NetworkDeviceInfo localhostInfo(QHostAddress::LocalHost);
+    localhostInfo.setHostName("localhost");
+    m_networkInfoCache.append(localhostInfo);
+
     // We just did some housekeeping while loading from the cache
     m_lastCacheHousekeeping = QDateTime::currentDateTime();
 }
@@ -630,7 +640,7 @@ void NetworkDeviceDiscoveryImpl::removeFromNetworkDeviceCache(const QHostAddress
 
 void NetworkDeviceDiscoveryImpl::saveNetworkDeviceCache(const NetworkDeviceInfo &deviceInfo)
 {
-    if (!deviceInfo.isValid() || !deviceInfo.isComplete())
+    if (!deviceInfo.isValid() || !deviceInfo.isComplete() || deviceInfo.address() == QHostAddress::LocalHost)
         return;
 
     m_cacheSettings->beginGroup("NetworkDeviceInfos");

libnymea-core/hardware/network/networkdevicediscoveryimpl.h

@@ -139,8 +139,6 @@ private:
 
     void processArpTraffic(const QNetworkInterface &interface, const QHostAddress &address, const MacAddress &macAddress);
 
-    void testPingMonitor(NetworkDeviceMonitorImpl *monitor);
-
     // Time helpers
     bool longerAgoThan(const QDateTime &dateTime, uint minutes);
     QDateTime convertMinuteBased(const QDateTime &dateTime = QDateTime());

libnymea/network/ping.cpp

@@ -162,7 +162,9 @@ void Ping::sendNextReply()
         return;
 
     m_currentReply = m_replyQueue.dequeue();
-    qCDebug(dcPing()).nospace().noquote() << "Send next reply " << m_currentReply->targetHostAddress().toString() << " ID: " << QString("0x%1").arg(m_currentReply->requestId(), 4, 16, QChar('0')) << ", " << m_replyQueue.count() << "left in queue";
+    qCDebug(dcPing()).nospace().noquote() << "Send next reply " << m_currentReply->targetHostAddress().toString()
+                                          << " ID: " << QString("0x%1").arg(m_currentReply->requestId(), 4, 16, QChar('0'))
+                                          << ", " << m_replyQueue.count() << " left in queue";
     m_queueTimer->start();
     QTimer::singleShot(0, this, [=]() {
         if (!m_currentReply)
@@ -195,8 +197,6 @@ void Ping::performPing(PingReply *reply)
     pingAddress.sin_port = 0;
     pingAddress.sin_addr.s_addr = *(long*)hostname->h_addr;
 
-    QHostAddress targetHostAddress = QHostAddress(qFromBigEndian(pingAddress.sin_addr.s_addr));
-
     // Build the ICMP echo request packet
     struct icmpPacket requestPacket;
     memset(&requestPacket, 0, sizeof(requestPacket));
@@ -593,10 +593,24 @@ void Ping::onHostLookupFinished(const QHostInfo &info)
                 qCWarning(dcPing()) << "Looked up address finished succesfully but there are no addresses available for" << info.hostName();
                 pingError = PingReply::ErrorHostNameNotFound;
             } else {
-                reply->m_targetHostAddress = info.addresses().first();
+                QHostAddress targetHostAddress;
+                foreach (const QHostAddress &lookedUpAddress, info.addresses()) {
+                    // Select the first valid IPv4 address, skip IPv6
+                    if (!lookedUpAddress.isNull() && lookedUpAddress.protocol() == QAbstractSocket::IPv4Protocol) {
+                        targetHostAddress = lookedUpAddress;
+                        break;
+                    }
+                }
+
+                if (targetHostAddress.isNull()) {
+                    qCDebug(dcPing()) << "No IPv4 address found in looked up addresses:" << reply->hostName() << info.addresses();
+                    pingError = PingReply::ErrorHostNameNotFound;
+                } else {
+                    reply->m_targetHostAddress = targetHostAddress;
                     reply->m_networkInterface = NetworkUtils::getInterfaceForHostaddress(reply->targetHostAddress());
                     pingError = PingReply::ErrorNoError;
                 }
+            }
             break;
         case QHostInfo::HostNotFound:
             qCDebug(dcPing()) << "Unable to find hostname:" << reply->hostName() << info.errorString();