Allow processing clipboard containing "secrets"

This allows processing the "secret" clipboard data by overriding new
`onSecretClipboardChanged()` script function.

This also ensures that callbacks are called consistently with properly
set formats `mimeClipboardMode`, `mimeOutputTab` and `mimeCurrentTab`.

Fixes #2787

docs/scripting-api.rst

@@ -1496,6 +1496,21 @@ unlike in GUI, where row numbers start from 1 by default.
 
    Default implementation calls :js:func:`updateClipboardData`.
 
+.. js:function:: onSecretClipboardChanged()
+
+   Called if the clipboard or `Linux mouse selection`_ changes and contains a
+   password or other secret (for example, copied from clipboard manager).
+
+   The default implementation clears all data, so they are not accessible using
+   :js:func:`data` and :js:func:`dataFormats`, except :js:data:`mimeSecret`,
+   and calls :js:func:`updateClipboardData`.
+
+   **Be careful overriding** this function (via a Script command). Calling
+   `onClipboardChanged()` without clearing the data and without any further
+   checks can cause storing and processing secrets from password managers. On
+   the other hand, it can help to get access to the data copied, for example
+   from a web browser in private mode.
+
 .. js:function:: onClipboardUnchanged()
 
    Called when clipboard or `Linux mouse selection`_ changes but data remained the same.
@@ -2212,8 +2227,6 @@ These MIME types values are assigned to global variables prefixed with
 
    If set to ``1``, the clipboard contains a password or other secret (for example, copied from clipboard manager).
 
-   In such case, the data won't be available in the app, not even via calling ``data()`` script function.
-
 .. js:data:: mimeShortcut
 
    Application or global shortcut which activated the command. Value: 'application/x-copyq-shortcut'.

src/app/clipboardmonitor.cpp

@@ -45,6 +45,11 @@ bool isClipboardDataHidden(const QVariantMap &data)
     return data.value(mimeHidden).toByteArray() == "1";
 }
 
+bool isClipboardDataSecret(const QVariantMap &data)
+{
+    return data.value(mimeSecret).toByteArray() == "1";
+}
+
 int defaultOwnerUpdateInterval()
 {
 #ifdef COPYQ_WS_X11
@@ -79,7 +84,8 @@ ClipboardMonitor::ClipboardMonitor(const QStringList &formats)
     m_storeSelection = config.option<Config::check_selection>();
     m_runSelection = config.option<Config::run_selection>();
 
-    m_clipboardToSelection = config.option<Config::copy_clipboard>();
+    m_clipboardToSelection = config.option<Config::copy_clipboard>()
+        && m_clipboard->isSelectionSupported();
     m_selectionToClipboard = config.option<Config::copy_selection>();
 
     if (!m_storeSelection && !m_runSelection && !m_selectionToClipboard) {
@@ -122,19 +128,15 @@ void ClipboardMonitor::onClipboardChanged(ClipboardMode mode)
     auto clipboardData = mode == ClipboardMode::Clipboard
             ? &m_clipboardData : &m_selectionData;
 
-    if ( hasSameData(data, *clipboardData) ) {
+    const bool isDataUnchanged = hasSameData(data, *clipboardData);
+    if (!isDataUnchanged) {
+        *clipboardData = data;
 #ifdef HAS_MOUSE_SELECTIONS
-        if ( !m_runSelection && mode == ClipboardMode::Selection )
-            return;
-#endif
-        COPYQ_LOG( QString("Ignoring unchanged %1")
-                   .arg(mode == ClipboardMode::Clipboard ? "clipboard" : "selection") );
-        emit clipboardUnchanged(data);
+    } else if (isDataUnchanged && !m_runSelection && mode == ClipboardMode::Selection) {
         return;
+#endif
     }
 
-    *clipboardData = data;
-
     if ( !data.contains(mimeOwner)
         && !data.contains(mimeWindowTitle)
         && !m_clipboardOwner.isEmpty() )
@@ -143,12 +145,33 @@ void ClipboardMonitor::onClipboardChanged(ClipboardMode mode)
     }
 
     COPYQ_LOG( QString("%1 changed, owner is \"%2\"")
-               .arg(mode == ClipboardMode::Clipboard ? "Clipboard" : "Selection",
+               .arg(QLatin1String(mode == ClipboardMode::Clipboard ? "Clipboard" : "Selection"),
                     getTextData(data, mimeOwner)) );
 
+    const auto defaultTab = m_clipboardTab.isEmpty() ? defaultClipboardTabName() : m_clipboardTab;
+    setTextData(&data, defaultTab, mimeCurrentTab);
+
+#ifdef HAS_MOUSE_SELECTIONS
+    if (mode == ClipboardMode::Selection)
+        data.insert(mimeClipboardMode, QByteArrayLiteral("selection"));
+
+    if (mode == ClipboardMode::Clipboard ? m_storeClipboard : m_storeSelection) {
+#else
+    if (m_storeClipboard) {
+#endif
+        setTextData(&data, m_clipboardTab, mimeOutputTab);
+    }
+
+    // if data themselves did not change, call just clipboardUnchanged()
+    if (isDataUnchanged) {
+        COPYQ_LOG( QStringLiteral("Ignoring unchanged %1")
+                   .arg(QLatin1String(mode == ClipboardMode::Clipboard ? "clipboard" : "selection")) );
+        emit clipboardUnchanged(data);
+        return;
+    }
+
 #ifdef HAS_MOUSE_SELECTIONS
     if ( (mode == ClipboardMode::Clipboard ? m_clipboardToSelection : m_selectionToClipboard)
-        && m_clipboard->isSelectionSupported()
         && !data.contains(mimeOwner) )
     {
         const auto text = getTextData(data);
@@ -165,40 +188,20 @@ void ClipboardMonitor::onClipboardChanged(ClipboardMode mode)
 
     // omit running run automatic commands when disabled
     if ( !m_runSelection && mode == ClipboardMode::Selection ) {
-        if ( m_storeSelection && !m_clipboardTab.isEmpty() ) {
-            data.insert(mimeClipboardMode, QByteArrayLiteral("selection"));
-            setTextData(&data, m_clipboardTab, mimeOutputTab);
+        if ( m_storeSelection && !m_clipboardTab.isEmpty() && !isClipboardDataSecret(data) )
             emit saveData(data);
-        }
         return;
     }
 #endif
 
-    if (mode != ClipboardMode::Clipboard) {
-        const QString modeName = mode == ClipboardMode::Selection
-                ? QStringLiteral("selection")
-                : QStringLiteral("find buffer");
-        data.insert(mimeClipboardMode, modeName);
-    }
-
-    // run automatic commands
-    if ( anySessionOwnsClipboardData(data) ) {
+    // run script callbacks
+    if ( isClipboardDataSecret(data) ) {
+        emit secretClipboardChanged(data);
+    } else if ( anySessionOwnsClipboardData(data) ) {
         emit clipboardChanged(data, ClipboardOwnership::Own);
     } else if ( isClipboardDataHidden(data) ) {
         emit clipboardChanged(data, ClipboardOwnership::Hidden);
     } else {
-        const auto defaultTab = m_clipboardTab.isEmpty() ? defaultClipboardTabName() : m_clipboardTab;
-        setTextData(&data, defaultTab, mimeCurrentTab);
-
-
-#ifdef HAS_MOUSE_SELECTIONS
-        if (mode == ClipboardMode::Clipboard ? m_storeClipboard : m_storeSelection) {
-#else
-        if (m_storeClipboard) {
-#endif
-            setTextData(&data, m_clipboardTab, mimeOutputTab);
-        }
-
         emit clipboardChanged(data, ClipboardOwnership::Foreign);
     }
 }

src/app/clipboardmonitor.h

@@ -28,6 +28,7 @@ class ClipboardMonitor final : public QObject
 
 signals:
     void clipboardChanged(const QVariantMap &data, ClipboardOwnership ownership);
+    void secretClipboardChanged(const QVariantMap &data);
     void clipboardUnchanged(const QVariantMap &data);
     void saveData(const QVariantMap &data);
     void synchronizeSelection(ClipboardMode sourceMode, uint sourceTextHash, uint targetTextHash);

src/gui/commandcompleterdocumentation.h

@@ -156,6 +156,7 @@ void addDocumentation(AddDocumentationCallback addDocumentation)
     addDocumentation("onClipboardChanged", "onClipboardChanged()", "Called when clipboard or `Linux mouse selection`_ changes.");
     addDocumentation("onOwnClipboardChanged", "onOwnClipboardChanged()", "Called when clipboard or `Linux mouse selection`_ changes by a CopyQ instance.");
     addDocumentation("onHiddenClipboardChanged", "onHiddenClipboardChanged()", "Called when hidden clipboard or `Linux mouse selection`_ changes.");
+    addDocumentation("onSecretClipboardChanged", "onSecretClipboardChanged()", "Called if the clipboard or `Linux mouse selection`_ changes and contains a password or other secret (for example, copied from clipboard manager).");
     addDocumentation("onClipboardUnchanged", "onClipboardUnchanged()", "Called when clipboard or `Linux mouse selection`_ changes but data remained the same.");
     addDocumentation("onStart", "onStart()", "Called when application starts.");
     addDocumentation("onExit", "onExit()", "Called just before application exists.");

src/platform/dummy/dummyclipboard.cpp

@@ -10,17 +10,6 @@
 #include <QMimeData>
 #include <QStringList>
 
-namespace {
-
-const QMimeData *createSecretData()
-{
-    auto data = new QMimeData();
-    data->setData(mimeSecret, QByteArrayLiteral("1"));
-    return data;
-}
-
-} // namespace
-
 QClipboard::Mode modeToQClipboardMode(ClipboardMode mode)
 {
     switch (mode) {
@@ -43,7 +32,15 @@ void DummyClipboard::startMonitoring(const QStringList &)
 QVariantMap DummyClipboard::data(ClipboardMode mode, const QStringList &formats) const
 {
     const QMimeData *data = mimeData(mode);
-    return data ? cloneData(*data, formats) : QVariantMap();
+    if (data == nullptr)
+        return {};
+
+    const bool isDataSecret = isHidden(*data);
+    QVariantMap dataMap = cloneData(*data, formats);
+    if (isDataSecret)
+        dataMap[mimeSecret] = QByteArrayLiteral("1");
+
+    return dataMap;
 }
 
 void DummyClipboard::setData(ClipboardMode mode, const QVariantMap &dataMap)
@@ -68,12 +65,6 @@ const QMimeData *DummyClipboard::mimeData(ClipboardMode mode) const
         return nullptr;
     }
 
-    if (isHidden(*data)) {
-        log( QStringLiteral("Hiding secret %1 data").arg(modeText) );
-        static const QMimeData *secretData = createSecretData();
-        return secretData;
-    }
-
     COPYQ_LOG_VERBOSE( QStringLiteral("Got %1 data").arg(modeText) );
     return data;
 }

src/platform/x11/x11platformclipboard.cpp

@@ -22,6 +22,7 @@
 
 #include <QClipboard>
 #include <QMimeData>
+#include <QPointer>
 
 namespace {
 
@@ -245,7 +246,7 @@ void X11PlatformClipboard::updateClipboardData(X11PlatformClipboard::ClipboardDa
         return;
     }
 
-    const auto data = mimeData(clipboardData->mode);
+    const QPointer<const QMimeData> data( mimeData(clipboardData->mode) );
 
     // Retry to retrieve clipboard data few times.
     if (!data) {
@@ -283,14 +284,17 @@ void X11PlatformClipboard::updateClipboardData(X11PlatformClipboard::ClipboardDa
     // text did not change.
     if ( newDataTimestamp != 0 && clipboardData->newDataTimestamp == newDataTimestamp ) {
         const QVariantMap newData = cloneData(*data, {mimeText});
-        if (newData.value(mimeText) == clipboardData->newData.value(mimeText))
+        if (!data || newData.value(mimeText) == clipboardData->newData.value(mimeText))
             return;
     }
 
     clipboardData->timerEmitChange.stop();
     clipboardData->abortCloning = false;
     clipboardData->cloningData = true;
+    const bool isDataSecret = isHidden(*data);
     clipboardData->newData = cloneData(*data, clipboardData->formats, &clipboardData->abortCloning);
+    if (isDataSecret)
+        clipboardData->newData[mimeSecret] = QByteArrayLiteral("1");
     clipboardData->cloningData = false;
     if (clipboardData->abortCloning) {
         m_timerCheckAgain.setInterval(0);

src/scriptable/scriptable.cpp

@@ -2382,6 +2382,13 @@ void Scriptable::onClipboardUnchanged()
 {
 }
 
+void Scriptable::onSecretClipboardChanged()
+{
+    // Drop secret data by default
+    m_data = {{mimeSecret, m_data.value(mimeSecret)}};
+    eval("updateClipboardData()");
+}
+
 void Scriptable::synchronizeToSelection()
 {
     if ( canSynchronizeSelection(ClipboardMode::Selection) ) {
@@ -2605,6 +2612,8 @@ void Scriptable::monitorClipboard()
     connect(this, &Scriptable::finished, &loop, &QEventLoop::quit);
     connect( &monitor, &ClipboardMonitor::clipboardChanged,
              this, &Scriptable::onMonitorClipboardChanged );
+    connect( &monitor, &ClipboardMonitor::secretClipboardChanged,
+             this, &Scriptable::onMonitorSecretClipboardChanged );
     connect( &monitor, &ClipboardMonitor::clipboardUnchanged,
              this, &Scriptable::onMonitorClipboardUnchanged );
     connect( &monitor, &ClipboardMonitor::synchronizeSelection,
@@ -2704,6 +2713,11 @@ void Scriptable::onMonitorClipboardChanged(const QVariantMap &data, ClipboardOwn
     m_proxy->runInternalAction(data, command);
 }
 
+void Scriptable::onMonitorSecretClipboardChanged(const QVariantMap &data)
+{
+    m_proxy->runInternalAction(data, QStringLiteral("copyq onSecretClipboardChanged"));
+}
+
 void Scriptable::onMonitorClipboardUnchanged(const QVariantMap &data)
 {
     m_proxy->runInternalAction(data, "copyq onClipboardUnchanged");

src/scriptable/scriptable.h

@@ -361,6 +361,7 @@ public slots:
     void onOwnClipboardChanged();
     void onHiddenClipboardChanged();
     void onClipboardUnchanged();
+    void onSecretClipboardChanged();
 
     void onStart() {}
     void onExit() {}
@@ -406,6 +407,7 @@ public slots:
 
 private:
     void onMonitorClipboardChanged(const QVariantMap &data, ClipboardOwnership ownership);
+    void onMonitorSecretClipboardChanged(const QVariantMap &data);
     void onMonitorClipboardUnchanged(const QVariantMap &data);
     void onSynchronizeSelection(ClipboardMode sourceMode, uint sourceTextHash, uint targetTextHash);
     void onFetchCurrentClipboardOwner(QString *title);

src/tests/tests.cpp

@@ -4854,14 +4854,13 @@ void Tests::startServerAndRunCommand()
 void Tests::avoidStoringPasswords()
 {
     TEST( m_test->setClipboard(secretData("secret")) );
-    waitFor(2 * waitMsPasteClipboard);
-    RUN("clipboard" << "?", mimeSecret + "\n");
+    WAIT_ON_OUTPUT("clipboard", "secret");
     RUN("read" << "0" << "1" << "2", "\n\n");
     RUN("count", "0\n");
 
     RUN("keys" << clipboardBrowserId << keyNameFor(QKeySequence::Paste), "");
     waitFor(waitMsPasteClipboard);
-    RUN("read" << "0" << "1" << "2", "\n\n");
+    RUN("read" << "0" << "1" << "2", "secret\n\n");
     RUN("count", "1\n");
 }
 
@@ -4870,15 +4869,14 @@ void Tests::scriptsForPasswords()
     const auto script = R"(
         setCommands([{
             isScript: true,
-            cmd: `global.updateClipboardData = function() {
-                if (data(mimeSecret) == "1") add("SECRET");
+            cmd: `global.onSecretClipboardChanged = function() {
+                add("SECRET");
             }`
         }])
         )";
     RUN(script, "");
     WAIT_ON_OUTPUT("commands().length", "1\n");
     TEST( m_test->setClipboard(secretData("secret")) );
-    waitFor(2 * waitMsPasteClipboard);
     WAIT_ON_OUTPUT("read" << "0" << "1" << "2", "SECRET\n\n");
     RUN("count", "1\n");
 }