Embedded: fix network detection

src/CMakeLists.txt

@@ -29,7 +29,7 @@ if (APPLE)
         dependencies/drivelist/src/darwin/list.mm dependencies/drivelist/src/darwin/REDiskList.m icons/rpi-imager.icns)
     enable_language(OBJC C)
 elseif (UNIX)
-    set(DEPENDENCIES dependencies/mountutils/src/linux/functions.cpp linux/linuxdrivelist.cpp linux/networkmanagerapi.h linux/networkmanagerapi.cpp)
+    set(DEPENDENCIES dependencies/mountutils/src/linux/functions.cpp linux/linuxdrivelist.cpp linux/networkmanagerapi.h linux/networkmanagerapi.cpp linux/stpanalyzer.h linux/stpanalyzer.cpp)
     find_package(ZLIB)
     if(ZLIB_FOUND)
         set(EXTRALIBS ${EXTRALIBS} ZLIB::ZLIB)

src/imagewriter.cpp

@@ -37,6 +37,8 @@
 #ifndef QT_NO_WIDGETS
 #include <QFileDialog>
 #include <QApplication>
+#else
+#include <QtPlatformHeaders/QEglFSFunctions>
 #endif
 #ifdef Q_OS_DARWIN
 #include <QMessageBox>
@@ -49,8 +51,8 @@
 #include <QProcessEnvironment>
 #endif
 
-#ifdef QT_NO_WIDGETS
-#include <QtPlatformHeaders/QEglFSFunctions>
+#ifdef Q_OS_LINUX
+#include "linux/stpanalyzer.h"
 #endif
 
 namespace {
@@ -75,6 +77,7 @@ ImageWriter::ImageWriter(QObject *parent)
         platform = "cli";
     }
 
+#ifdef Q_OS_LINUX
     if (platform == "eglfs" || platform == "linuxfb")
     {
         _embeddedMode = true;
@@ -98,7 +101,12 @@ ImageWriter::ImageWriter(QObject *parent)
                 }
             }
         }
+
+        StpAnalyzer *stpAnalyzer = new StpAnalyzer(5, this);
+        connect(stpAnalyzer, SIGNAL(detected()), SLOT(onSTPdetected()));
+        stpAnalyzer->startListening("eth0");
     }
+#endif
 
 #ifdef Q_OS_WIN
     _taskbarButton = nullptr;
@@ -923,7 +931,7 @@ void ImageWriter::pollNetwork()
         if (!a.isLoopback() && a.scopeId().isEmpty())
         {
             /* Not a loopback or IPv6 link-local address, so online */
-            qDebug() << "IP:" << a;
+            emit networkInfo(QString("IP: %1").arg(a.toString()));
             _online = true;
             break;
         }
@@ -961,11 +969,12 @@ void ImageWriter::onTimeSyncReply(QNetworkReply *reply)
         };
         ::settimeofday(&tv, NULL);
 
+        beginOSListFetch();
         emit networkOnline();
     }
     else
     {
-        qDebug() << "Error synchronizing time. Trying again in 3 seconds";
+        emit networkInfo(tr("Error synchronizing time. Trying again in 3 seconds"));
         QTimer::singleShot(3000, this, SLOT(syncTime()));
     }
 
@@ -975,6 +984,11 @@ void ImageWriter::onTimeSyncReply(QNetworkReply *reply)
 #endif
 }
 
+void ImageWriter::onSTPdetected()
+{
+    emit networkInfo(tr("STP is enabled on your Ethernet switch. Getting IP will take long time."));
+}
+
 bool ImageWriter::isEmbeddedMode()
 {
     return _embeddedMode;

src/imagewriter.h

@@ -159,6 +159,7 @@ signals:
     void networkOnline();
     void preparationStatusUpdate(QVariant msg);
     void osListPrepared();
+    void networkInfo(QVariant msg);
 
 protected slots:
 
@@ -176,6 +177,7 @@ protected slots:
     void onTimeSyncReply(QNetworkReply *reply);
     void onPreparationStatusUpdate(QString msg);
     void handleNetworkRequestFinished(QNetworkReply *data);
+    void onSTPdetected();
 
 private:
     // Recursively walk all the entries with subitems and, for any which

src/linux/stpanalyzer.cpp

@@ -0,0 +1,118 @@
+/**
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright (C) 2024 Raspberry Pi Ltd
+ *
+ * Class to detect if the Spanning-Tree-Protocol
+ * is enabled on the Ethernet switch (which can
+ * cause a long delay in getting an IP-address)
+ */
+
+#include "stpanalyzer.h"
+#include <cstdint>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <linux/if_ether.h>
+#include <linux/if_packet.h>
+#include <net/if.h>
+#include <QSocketNotifier>
+#include <QtEndian>
+
+struct stp_packet {
+    /* Ethernet header */
+    struct ethhdr eth;
+    /* 802.2 LLC header */
+    uint8_t dsap, ssap, control;
+    /* STP fields */
+    uint16_t protocol;
+    uint8_t  version;
+    uint8_t  msgtype;
+    uint8_t  flags;
+    uint16_t rootpriority;
+    unsigned char rootmac[6];
+    uint32_t rootpathcost;
+    uint16_t bridgepriority;
+    unsigned char bridgemac[6];
+    uint16_t portid;
+    uint16_t msgage;
+    uint16_t maxage;
+    uint16_t hellotime;
+    uint16_t forwarddelay;
+} __attribute__((__packed__));
+
+#define LSAP_BDPU  0x42
+#define MULTICAST_MAC_BDPU   {0x1, 0x80, 0xC2, 0, 0, 0}
+#define MULTICAST_MAC_BDPUPV {0x1, 0, 0x0C, 0xCC, 0xCC, 0xCD}
+
+StpAnalyzer::StpAnalyzer(int onlyReportIfForwardDelayIsAbove, QObject *parent)
+    : QObject(parent), _s(-1), _minForwardDelay(onlyReportIfForwardDelayIsAbove), _qsn(nullptr)
+{
+}
+
+StpAnalyzer::~StpAnalyzer()
+{
+    stopListening();
+}
+
+void StpAnalyzer::startListening(const QByteArray &ifname)
+{
+    int iface;
+
+    if (_s != -1)
+        return; /* Already listening */
+
+    _s = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_802_2));
+    if (_s < 0)
+    {
+        return;
+    }
+
+    iface = if_nametoindex(ifname.constData());
+    if (!iface) {
+        return;
+    }
+
+    struct packet_mreq mreq = { iface, PACKET_MR_MULTICAST, ETH_ALEN, MULTICAST_MAC_BDPU };
+    setsockopt(_s, SOL_PACKET, PACKET_ADD_MEMBERSHIP, &mreq, sizeof(mreq));
+    struct packet_mreq mreq2 = { iface, PACKET_MR_MULTICAST, ETH_ALEN, MULTICAST_MAC_BDPUPV };
+    setsockopt(_s, SOL_PACKET, PACKET_ADD_MEMBERSHIP, &mreq2, sizeof(mreq2));
+
+    _qsn = new QSocketNotifier(_s, QSocketNotifier::Read, this);
+    connect(_qsn, SIGNAL(activated(QSocketDescriptor,QSocketNotifier::Type)), SLOT(onPacket(QSocketDescriptor,QSocketNotifier::Type)));
+}
+
+void StpAnalyzer::stopListening()
+{
+    if (_s != -1)
+    {
+        _qsn->setEnabled(false);
+        _qsn->deleteLater();
+        _qsn = nullptr;
+        close(_s);
+        _s = -1;
+    }
+}
+
+void StpAnalyzer::onPacket(QSocketDescriptor socket, QSocketNotifier::Type type)
+{
+    struct stp_packet packet = { 0 };
+
+    int len = recvfrom(_s, &packet, sizeof(packet), 0, NULL, 0);
+
+    if (len == sizeof(packet)
+            && packet.dsap == LSAP_BDPU
+            && packet.ssap == LSAP_BDPU
+            && packet.protocol == 0)
+    {
+        /* It is a STP packet */
+        int forwardDelay = qFromLittleEndian(packet.forwarddelay);
+        if (forwardDelay > _minForwardDelay)
+        {
+            emit detected();
+        }
+
+        /* Only analyze first packet */
+        stopListening();
+    }
+}

src/linux/stpanalyzer.h

@@ -0,0 +1,32 @@
+#ifndef STPANALYZER_H
+#define STPANALYZER_H
+
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright (C) 2024 Raspberry Pi Ltd
+ */
+
+#include <QObject>
+#include <QSocketNotifier>
+
+class StpAnalyzer : public QObject
+{
+    Q_OBJECT
+public:
+    StpAnalyzer(int onlyReportIfForwardDelayIsAbove = 5, QObject *parent = nullptr);
+    virtual ~StpAnalyzer();
+    void startListening(const QByteArray &ifname);
+    void stopListening();
+
+signals:
+    void detected();
+
+protected:
+    int _s, _minForwardDelay;
+    QSocketNotifier *_qsn;
+
+protected slots:
+    void onPacket(QSocketDescriptor socket, QSocketNotifier::Type type);
+};
+
+#endif // STPANALYZER_H

src/main.cpp

@@ -347,6 +347,7 @@ int main(int argc, char *argv[])
     qmlwindow->connect(&imageWriter, SIGNAL(finalizing()), qmlwindow, SLOT(onFinalizing()));
     qmlwindow->connect(&imageWriter, SIGNAL(networkOnline()), qmlwindow, SLOT(fetchOSlist()));
     qmlwindow->connect(&imageWriter, SIGNAL(osListPrepared()), qmlwindow, SLOT(onOsListPrepared()));
+    qmlwindow->connect(&imageWriter, SIGNAL(networkInfo(QVariant)), qmlwindow, SLOT(onNetworkInfo(QVariant)));
 
 #ifndef QT_NO_WIDGETS
     /* Set window position */
@@ -375,7 +376,8 @@ int main(int argc, char *argv[])
     qmlwindow->setProperty("y", y);
 #endif
 
-    imageWriter.beginOSListFetch();
+    if (imageWriter.isOnline())
+        imageWriter.beginOSListFetch();
 
     int rc = app.exec();
 

src/main.qml

@@ -320,6 +320,16 @@ ApplicationWindow {
                     text: qsTr("Using custom repository: %1").arg(imageWriter.constantOsListUrl())
                 }
 
+                Text {
+                    id: networkInfo
+                    Layout.columnSpan: 3
+                    color: "#ffffff"
+                    font.pixelSize: 18
+                    font.family: roboto.name
+                    visible: imageWriter.isEmbeddedMode()
+                    text: qsTr("Network not ready yet")
+                }
+
                 Text {
                     Layout.columnSpan: 3
                     color: "#ffffff"
@@ -1316,6 +1326,10 @@ ApplicationWindow {
         progressText.text = qsTr("Finalizing...")
     }
 
+    function onNetworkInfo(msg) {
+        networkInfo.text = msg
+    }
+
     function shuffle(arr) {
         for (var i = 0; i < arr.length - 1; i++) {
             var j = i + Math.floor(Math.random() * (arr.length - i));