Server-Config UI (aktiv/passiv) und Port-Forwarding Tipps in README

- FTP-Tab: Server Configuration mit Active/Passive Radio-Buttons
- Passive Mode: Port-Range konfigurierbar (Default 30000-31000)
- Apply-Button startet Pure-FTPd automatisch neu
- Helper-Script: serverconfig show/active/passive Kommandos
- sudoers: systemctl restart, tee und rm für Pure-FTPd Config
- README: Port-Forwarding Anleitung für Windows (netsh) und Linux (socat/iptables)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

README.md

@@ -211,6 +211,96 @@ kde-dolphin-ftp-sharing-tab/
 | `ro` | Read Only — nur Download |
 | `rw` | Read-Write — Upload und Download |
 
+## Tipps: Port-Forwarding für FTP
+
+### Szenario
+
+Ein Gerät (z.B. ein Dokumentenscanner) soll per FTP auf den Server scannen, hat aber **keinen direkten Zugang** zum Server-Netzwerk (z.B. VPN). Ein Windows- oder Linux-Rechner, der in **beiden Netzen** hängt, leitet die FTP-Ports weiter.
+
+```
+Scanner ──► Windows/Linux (Port-Forwarding) ──► VPN ──► FTP-Server
+```
+
+### Aktiver Modus (empfohlen für Port-Forwarding)
+
+Im aktiven Modus müssen nur **2 Ports** weitergeleitet werden: **20** (Daten) und **21** (Steuerung).
+
+### Passiver Modus
+
+Im passiven Modus muss zusätzlich die **gesamte Port-Range** weitergeleitet werden (z.B. 30000-31000). Das ist aufwändiger, aber nötig wenn aktiver Modus nicht funktioniert.
+
+### Windows: Port-Forwarding mit netsh
+
+Als Administrator in der Eingabeaufforderung (cmd):
+
+```batch
+:: Aktiver Modus — Port 21 (Steuerung) und Port 20 (Daten) weiterleiten
+netsh interface portproxy add v4tov4 listenport=21 listenaddress=0.0.0.0 connectport=21 connectaddress=<SERVER-VPN-IP>
+netsh interface portproxy add v4tov4 listenport=20 listenaddress=0.0.0.0 connectport=20 connectaddress=<SERVER-VPN-IP>
+
+:: Passiver Modus — zusätzlich die Port-Range weiterleiten
+:: (PowerShell, da netsh keine Ranges unterstützt)
+for ($p=30000; $p -le 31000; $p++) { netsh interface portproxy add v4tov4 listenport=$p listenaddress=0.0.0.0 connectport=$p connectaddress=<SERVER-VPN-IP> }
+```
+
+**Windows-Firewall öffnen:**
+
+```batch
+netsh advfirewall firewall add rule name="FTP Active" dir=in action=allow protocol=TCP localport=20,21
+:: Für passiven Modus zusätzlich:
+netsh advfirewall firewall add rule name="FTP Passive" dir=in action=allow protocol=TCP localport=30000-31000
+```
+
+**Port-Forwarding anzeigen / entfernen:**
+
+```batch
+:: Alle Weiterleitungen anzeigen
+netsh interface portproxy show all
+
+:: Einzelne Weiterleitung entfernen
+netsh interface portproxy delete v4tov4 listenport=21 listenaddress=0.0.0.0
+
+:: Alle Weiterleitungen entfernen
+netsh interface portproxy reset
+```
+
+### Linux: Port-Forwarding mit iptables oder socat
+
+**Variante 1: socat (einfach, gut zum Testen)**
+
+```bash
+# Aktiver Modus
+sudo socat TCP-LISTEN:21,fork,reuseaddr TCP:<SERVER-VPN-IP>:21 &
+sudo socat TCP-LISTEN:20,fork,reuseaddr TCP:<SERVER-VPN-IP>:20 &
+
+# Passiver Modus — zusätzlich Port-Range
+for p in $(seq 30000 31000); do
+    sudo socat TCP-LISTEN:$p,fork,reuseaddr TCP:<SERVER-VPN-IP>:$p &
+done
+```
+
+**Variante 2: iptables (performanter, dauerhaft)**
+
+```bash
+# IP-Forwarding aktivieren
+sudo sysctl -w net.ipv4.ip_forward=1
+
+# Aktiver Modus
+sudo iptables -t nat -A PREROUTING -p tcp --dport 21 -j DNAT --to-destination <SERVER-VPN-IP>:21
+sudo iptables -t nat -A PREROUTING -p tcp --dport 20 -j DNAT --to-destination <SERVER-VPN-IP>:20
+sudo iptables -t nat -A POSTROUTING -j MASQUERADE
+
+# Passiver Modus — zusätzlich Port-Range
+sudo iptables -t nat -A PREROUTING -p tcp --dport 30000:31000 -j DNAT --to-destination <SERVER-VPN-IP>
+```
+
+**Dauerhaft speichern:**
+
+```bash
+sudo apt install iptables-persistent
+sudo netfilter-persistent save
+```
+
 ## Lizenz
 
 GPLv2+

kf5/src/ftpshareplugin.cpp

@@ -5,6 +5,7 @@
 
 #include <QFormLayout>
 #include <QGroupBox>
+#include <QHBoxLayout>
 #include <QInputDialog>
 #include <QLabel>
 #include <QMessageBox>
@@ -152,6 +153,47 @@ FtpSharePlugin::FtpSharePlugin(QObject *parent, const QVariantList &args)
 
     connect(pwButton, &QPushButton::clicked, this, &FtpSharePlugin::onChangePassword);
 
+    // Server configuration section
+    auto *serverGroup = new QGroupBox(i18n("Server Configuration"));
+    auto *serverLayout = new QVBoxLayout(serverGroup);
+
+    // Active mode
+    m_activeRadio = new QRadioButton(i18n("Active Mode (Port 20)"));
+    serverLayout->addWidget(m_activeRadio);
+
+    // Passive mode
+    m_passiveRadio = new QRadioButton(i18n("Passive Mode"));
+    serverLayout->addWidget(m_passiveRadio);
+
+    // Passive port range
+    m_passivePortsWidget = new QWidget();
+    auto *passivePortsLayout = new QHBoxLayout(m_passivePortsWidget);
+    passivePortsLayout->setContentsMargins(20, 0, 0, 0);
+    passivePortsLayout->addWidget(new QLabel(i18n("Port-Range:")));
+    m_passiveStartSpin = new QSpinBox();
+    m_passiveStartSpin->setRange(1024, 65535);
+    m_passiveStartSpin->setValue(30000);
+    passivePortsLayout->addWidget(m_passiveStartSpin);
+    passivePortsLayout->addWidget(new QLabel(QStringLiteral("-")));
+    m_passiveEndSpin = new QSpinBox();
+    m_passiveEndSpin->setRange(1024, 65535);
+    m_passiveEndSpin->setValue(31000);
+    passivePortsLayout->addWidget(m_passiveEndSpin);
+    passivePortsLayout->addStretch();
+    serverLayout->addWidget(m_passivePortsWidget);
+
+    // Apply button
+    auto *applyServerBtn = new QPushButton(i18n("Apply Server Config"));
+    serverLayout->addWidget(applyServerBtn);
+
+    mainLayout->addWidget(serverGroup);
+
+    connect(m_activeRadio, &QRadioButton::toggled, this, &FtpSharePlugin::onModeChanged);
+    connect(applyServerBtn, &QPushButton::clicked, this, &FtpSharePlugin::onApplyServerConfig);
+
+    // Load current server config
+    loadServerConfig();
+
     mainLayout->addStretch();
 
     // Connect signals
@@ -335,6 +377,71 @@ void FtpSharePlugin::applyChanges()
     }
 }
 
+void FtpSharePlugin::loadServerConfig()
+{
+    QProcess proc;
+    proc.start(QStringLiteral("dolphin-ftp-share"),
+               {QStringLiteral("serverconfig"), QStringLiteral("show")});
+    proc.waitForFinished(5000);
+
+    const QString output = QString::fromLocal8Bit(proc.readAllStandardOutput());
+    bool isPassive = false;
+    int startPort = 30000;
+    int endPort = 31000;
+
+    const QStringList lines = output.split(QLatin1Char('\n'));
+    for (const QString &line : lines) {
+        if (line.startsWith(QLatin1String("mode=passive")))
+            isPassive = true;
+        else if (line.startsWith(QLatin1String("passive_start=")))
+            startPort = line.mid(14).toInt();
+        else if (line.startsWith(QLatin1String("passive_end=")))
+            endPort = line.mid(12).toInt();
+    }
+
+    if (isPassive) {
+        m_passiveRadio->setChecked(true);
+        m_passiveStartSpin->setValue(startPort);
+        m_passiveEndSpin->setValue(endPort);
+    } else {
+        m_activeRadio->setChecked(true);
+    }
+    onModeChanged();
+}
+
+void FtpSharePlugin::onModeChanged()
+{
+    m_passivePortsWidget->setEnabled(m_passiveRadio->isChecked());
+}
+
+void FtpSharePlugin::onApplyServerConfig()
+{
+    QProcess proc;
+    if (m_activeRadio->isChecked()) {
+        proc.start(QStringLiteral("dolphin-ftp-share"),
+                   {QStringLiteral("serverconfig"), QStringLiteral("active")});
+    } else {
+        proc.start(QStringLiteral("dolphin-ftp-share"),
+                   {QStringLiteral("serverconfig"), QStringLiteral("passive"),
+                    QString::number(m_passiveStartSpin->value()),
+                    QString::number(m_passiveEndSpin->value())});
+    }
+    proc.waitForFinished(10000);
+
+    if (proc.exitCode() == 0) {
+        QMessageBox::information(m_page,
+            i18n("Server Configuration"),
+            m_activeRadio->isChecked()
+                ? i18n("Server set to active mode (Port 20).\nPure-FTPd restarted.")
+                : i18n("Server set to passive mode (Ports %1-%2).\nPure-FTPd restarted.",
+                        m_passiveStartSpin->value(), m_passiveEndSpin->value()));
+    } else {
+        QMessageBox::warning(m_page,
+            i18n("Server Configuration"),
+            i18n("Failed to apply server configuration."));
+    }
+}
+
 void FtpSharePlugin::onChangePassword()
 {
     const QString username = m_pwUserCombo->currentText();

kf5/src/ftpshareplugin.h

@@ -6,6 +6,8 @@
 #include <QComboBox>
 #include <QLineEdit>
 #include <QPushButton>
+#include <QRadioButton>
+#include <QSpinBox>
 #include <QWidget>
 
 struct UserPermission {
@@ -22,8 +24,11 @@ public:
 
 private:
     void loadCurrentShare();
+    void loadServerConfig();
     void onShareToggled(bool checked);
     void onChangePassword();
+    void onApplyServerConfig();
+    void onModeChanged();
 
     QString m_path;
     QString m_defaultShareName;
@@ -34,6 +39,13 @@ private:
     QWidget *m_usersWidget = nullptr;
     QComboBox *m_pwUserCombo = nullptr;
 
+    // Server config
+    QRadioButton *m_activeRadio = nullptr;
+    QRadioButton *m_passiveRadio = nullptr;
+    QSpinBox *m_passiveStartSpin = nullptr;
+    QSpinBox *m_passiveEndSpin = nullptr;
+    QWidget *m_passivePortsWidget = nullptr;
+
     QVector<UserPermission> m_userPerms;
 
     bool m_isShared = false;

kf6/src/ftpshareplugin.cpp

@@ -5,6 +5,7 @@
 
 #include <QFormLayout>
 #include <QGroupBox>
+#include <QHBoxLayout>
 #include <QInputDialog>
 #include <QLabel>
 #include <QMessageBox>
@@ -152,6 +153,47 @@ FtpSharePlugin::FtpSharePlugin(QObject *parent, const QVariantList &args)
 
     connect(pwButton, &QPushButton::clicked, this, &FtpSharePlugin::onChangePassword);
 
+    // Server configuration section
+    auto *serverGroup = new QGroupBox(i18n("Server Configuration"));
+    auto *serverLayout = new QVBoxLayout(serverGroup);
+
+    // Active mode
+    m_activeRadio = new QRadioButton(i18n("Active Mode (Port 20)"));
+    serverLayout->addWidget(m_activeRadio);
+
+    // Passive mode
+    m_passiveRadio = new QRadioButton(i18n("Passive Mode"));
+    serverLayout->addWidget(m_passiveRadio);
+
+    // Passive port range
+    m_passivePortsWidget = new QWidget();
+    auto *passivePortsLayout = new QHBoxLayout(m_passivePortsWidget);
+    passivePortsLayout->setContentsMargins(20, 0, 0, 0);
+    passivePortsLayout->addWidget(new QLabel(i18n("Port-Range:")));
+    m_passiveStartSpin = new QSpinBox();
+    m_passiveStartSpin->setRange(1024, 65535);
+    m_passiveStartSpin->setValue(30000);
+    passivePortsLayout->addWidget(m_passiveStartSpin);
+    passivePortsLayout->addWidget(new QLabel(QStringLiteral("-")));
+    m_passiveEndSpin = new QSpinBox();
+    m_passiveEndSpin->setRange(1024, 65535);
+    m_passiveEndSpin->setValue(31000);
+    passivePortsLayout->addWidget(m_passiveEndSpin);
+    passivePortsLayout->addStretch();
+    serverLayout->addWidget(m_passivePortsWidget);
+
+    // Apply button
+    auto *applyServerBtn = new QPushButton(i18n("Apply Server Config"));
+    serverLayout->addWidget(applyServerBtn);
+
+    mainLayout->addWidget(serverGroup);
+
+    connect(m_activeRadio, &QRadioButton::toggled, this, &FtpSharePlugin::onModeChanged);
+    connect(applyServerBtn, &QPushButton::clicked, this, &FtpSharePlugin::onApplyServerConfig);
+
+    // Load current server config
+    loadServerConfig();
+
     mainLayout->addStretch();
 
     // Connect signals
@@ -335,6 +377,71 @@ void FtpSharePlugin::applyChanges()
     }
 }
 
+void FtpSharePlugin::loadServerConfig()
+{
+    QProcess proc;
+    proc.start(QStringLiteral("dolphin-ftp-share"),
+               {QStringLiteral("serverconfig"), QStringLiteral("show")});
+    proc.waitForFinished(5000);
+
+    const QString output = QString::fromLocal8Bit(proc.readAllStandardOutput());
+    bool isPassive = false;
+    int startPort = 30000;
+    int endPort = 31000;
+
+    const QStringList lines = output.split(QLatin1Char('\n'));
+    for (const QString &line : lines) {
+        if (line.startsWith(QLatin1String("mode=passive")))
+            isPassive = true;
+        else if (line.startsWith(QLatin1String("passive_start=")))
+            startPort = line.mid(14).toInt();
+        else if (line.startsWith(QLatin1String("passive_end=")))
+            endPort = line.mid(12).toInt();
+    }
+
+    if (isPassive) {
+        m_passiveRadio->setChecked(true);
+        m_passiveStartSpin->setValue(startPort);
+        m_passiveEndSpin->setValue(endPort);
+    } else {
+        m_activeRadio->setChecked(true);
+    }
+    onModeChanged();
+}
+
+void FtpSharePlugin::onModeChanged()
+{
+    m_passivePortsWidget->setEnabled(m_passiveRadio->isChecked());
+}
+
+void FtpSharePlugin::onApplyServerConfig()
+{
+    QProcess proc;
+    if (m_activeRadio->isChecked()) {
+        proc.start(QStringLiteral("dolphin-ftp-share"),
+                   {QStringLiteral("serverconfig"), QStringLiteral("active")});
+    } else {
+        proc.start(QStringLiteral("dolphin-ftp-share"),
+                   {QStringLiteral("serverconfig"), QStringLiteral("passive"),
+                    QString::number(m_passiveStartSpin->value()),
+                    QString::number(m_passiveEndSpin->value())});
+    }
+    proc.waitForFinished(10000);
+
+    if (proc.exitCode() == 0) {
+        QMessageBox::information(m_page,
+            i18n("Server Configuration"),
+            m_activeRadio->isChecked()
+                ? i18n("Server set to active mode (Port 20).\nPure-FTPd restarted.")
+                : i18n("Server set to passive mode (Ports %1-%2).\nPure-FTPd restarted.",
+                        m_passiveStartSpin->value(), m_passiveEndSpin->value()));
+    } else {
+        QMessageBox::warning(m_page,
+            i18n("Server Configuration"),
+            i18n("Failed to apply server configuration."));
+    }
+}
+
 void FtpSharePlugin::onChangePassword()
 {
     const QString username = m_pwUserCombo->currentText();

kf6/src/ftpshareplugin.h

@@ -6,6 +6,8 @@
 #include <QComboBox>
 #include <QLineEdit>
 #include <QPushButton>
+#include <QRadioButton>
+#include <QSpinBox>
 #include <QWidget>
 
 struct UserPermission {
@@ -22,8 +24,11 @@ public:
 
 private:
     void loadCurrentShare();
+    void loadServerConfig();
     void onShareToggled(bool checked);
     void onChangePassword();
+    void onApplyServerConfig();
+    void onModeChanged();
 
     QString m_path;
     QString m_defaultShareName;
@@ -34,6 +39,13 @@ private:
     QWidget *m_usersWidget = nullptr;
     QComboBox *m_pwUserCombo = nullptr;
 
+    // Server config
+    QRadioButton *m_activeRadio = nullptr;
+    QRadioButton *m_passiveRadio = nullptr;
+    QSpinBox *m_passiveStartSpin = nullptr;
+    QSpinBox *m_passiveEndSpin = nullptr;
+    QWidget *m_passivePortsWidget = nullptr;
+
     QVector<UserPermission> m_userPerms;
 
     bool m_isShared = false;

scripts/dolphin-ftp-share

@@ -92,6 +92,10 @@ ${REAL_USER} ALL=(root) NOPASSWD: /usr/bin/mount --bind *
 ${REAL_USER} ALL=(root) NOPASSWD: /usr/bin/mount -o remount?ro?bind *
 ${REAL_USER} ALL=(root) NOPASSWD: /usr/bin/umount ${REAL_FTP_ROOT}/*
 ${REAL_USER} ALL=(root) NOPASSWD: /usr/bin/pure-pw *
+${REAL_USER} ALL=(root) NOPASSWD: /usr/bin/tee /etc/pure-ftpd/conf/*
+${REAL_USER} ALL=(root) NOPASSWD: /usr/bin/rm -f /etc/pure-ftpd/conf/PassivePortRange
+${REAL_USER} ALL=(root) NOPASSWD: /usr/bin/sed -i *pureftpd.passwd*
+${REAL_USER} ALL=(root) NOPASSWD: /usr/bin/systemctl restart pure-ftpd
 EOF
     sudo chmod 440 /etc/sudoers.d/dolphin-ftp-share
 
@@ -225,15 +229,56 @@ cmd_passwd() {
     rebuild_db
 }
 
+cmd_serverconfig() {
+    local action="$1"
+
+    case "$action" in
+        show)
+            # Output current mode and ports
+            if [ -f /etc/pure-ftpd/conf/PassivePortRange ]; then
+                local range
+                range=$(cat /etc/pure-ftpd/conf/PassivePortRange)
+                echo "mode=passive"
+                echo "passive_start=${range%% *}"
+                echo "passive_end=${range##* }"
+            else
+                echo "mode=active"
+            fi
+            ;;
+        active)
+            # Remove passive port range → only active mode
+            sudo rm -f /etc/pure-ftpd/conf/PassivePortRange
+            sudo systemctl restart pure-ftpd
+            echo "Server set to active mode"
+            ;;
+        passive)
+            local start_port="$2"
+            local end_port="$3"
+            if [ -z "$start_port" ] || [ -z "$end_port" ]; then
+                echo "Error: start and end port required" >&2
+                exit 1
+            fi
+            echo "${start_port} ${end_port}" | sudo tee /etc/pure-ftpd/conf/PassivePortRange >/dev/null
+            sudo systemctl restart pure-ftpd
+            echo "Server set to passive mode (ports ${start_port}-${end_port})"
+            ;;
+        *)
+            echo "Usage: dolphin-ftp-share serverconfig {show|active|passive <start> <end>}" >&2
+            exit 1
+            ;;
+    esac
+}
+
 case "${1:-}" in
-    setup)      cmd_setup ;;
+    setup)        cmd_setup ;;
-    info)       cmd_info ;;
+    info)         cmd_info ;;
-    add)        cmd_add "$2" "$3" "${4:-}" ;;
+    add)          cmd_add "$2" "$3" "${4:-}" ;;
-    delete)     cmd_delete "$2" ;;
+    delete)       cmd_delete "$2" ;;
-    userexists) cmd_userexists "$2" ;;
+    userexists)   cmd_userexists "$2" ;;
-    passwd)     cmd_passwd "$2" "$3" ;;
+    passwd)       cmd_passwd "$2" "$3" ;;
+    serverconfig) cmd_serverconfig "$2" "$3" "$4" ;;
     *)
-        echo "Usage: dolphin-ftp-share {setup|info|add|delete|userexists|passwd}" >&2
+        echo "Usage: dolphin-ftp-share {setup|info|add|delete|userexists|passwd|serverconfig}" >&2
         echo "" >&2
         echo "Commands:" >&2
         echo "  setup                             Initial Pure-FTPd setup" >&2
@@ -242,6 +287,9 @@ case "${1:-}" in
         echo "  delete <name>                     Remove a share" >&2
         echo "  userexists <username>              Check if FTP user exists" >&2
         echo "  passwd <username> <password>       Set/create FTP password" >&2
+        echo "  serverconfig show                  Show current server config" >&2
+        echo "  serverconfig active                Set active mode" >&2
+        echo "  serverconfig passive <start> <end> Set passive mode with port range" >&2
         exit 1
         ;;
 esac