From d334a2e5e2b1b808b5622a14d46eabd0dba278c4 Mon Sep 17 00:00:00 2001
From: humbletim <humbletim@gmail.com>
Date: Thu, 25 Jul 2019 21:50:58 -0400
Subject: [PATCH] QML-only write access for 'private/' Settings keys

---
 interface/src/Application.cpp                         |  4 ++--
 .../src/scripting/SettingsScriptingInterface.cpp      |  9 +++++++++
 interface/src/scripting/SettingsScriptingInterface.h  | 11 ++++++++++-
 3 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/interface/src/Application.cpp b/interface/src/Application.cpp
index 0b56b2a4d7..a20d6dd440 100644
--- a/interface/src/Application.cpp
+++ b/interface/src/Application.cpp
@@ -3393,7 +3393,7 @@ void Application::onDesktopRootContextCreated(QQmlContext* surfaceContext) {
     surfaceContext->setContextProperty("Window", DependencyManager::get<WindowScriptingInterface>().data());
     surfaceContext->setContextProperty("Desktop", DependencyManager::get<DesktopScriptingInterface>().data());
     surfaceContext->setContextProperty("MenuInterface", MenuScriptingInterface::getInstance());
-    surfaceContext->setContextProperty("Settings", SettingsScriptingInterface::getInstance());
+    surfaceContext->setContextProperty("Settings", new QMLSettingsScriptingInterface(surfaceContext));
     surfaceContext->setContextProperty("ScriptDiscoveryService", DependencyManager::get<ScriptEngines>().data());
     surfaceContext->setContextProperty("AvatarBookmarks", DependencyManager::get<AvatarBookmarks>().data());
     surfaceContext->setContextProperty("LocationBookmarks", DependencyManager::get<LocationBookmarks>().data());
@@ -3509,7 +3509,7 @@ void Application::setupQmlSurface(QQmlContext* surfaceContext, bool setAdditiona
         surfaceContext->setContextProperty("offscreenFlags", flags);
         surfaceContext->setContextProperty("AddressManager", DependencyManager::get<AddressManager>().data());
 
-        surfaceContext->setContextProperty("Settings", SettingsScriptingInterface::getInstance());
+        surfaceContext->setContextProperty("Settings", new QMLSettingsScriptingInterface(surfaceContext));
         surfaceContext->setContextProperty("MenuInterface", MenuScriptingInterface::getInstance());
         surfaceContext->setContextProperty("Performance", new PerformanceScriptingInterface());
 
diff --git a/interface/src/scripting/SettingsScriptingInterface.cpp b/interface/src/scripting/SettingsScriptingInterface.cpp
index afafe1a350..a118f9cf4f 100644
--- a/interface/src/scripting/SettingsScriptingInterface.cpp
+++ b/interface/src/scripting/SettingsScriptingInterface.cpp
@@ -11,6 +11,7 @@
 
 #include "SettingsScriptingInterface.h"
 
+#include <QtScript/QScriptContext>
 #include <SettingHandle.h>
 
 SettingsScriptingInterface* SettingsScriptingInterface::getInstance() {
@@ -35,6 +36,14 @@ QVariant SettingsScriptingInterface::getValue(const QString& setting, const QVar
 }
 
 void SettingsScriptingInterface::setValue(const QString& setting, const QVariant& value) {
+    if (setting.startsWith("private/")) {
+        if (_restrictPrivateValues) {
+            qWarning() << "SettingsScriptingInterface::setValue -- restricted write: " << setting << value;
+            return;
+        } else {
+            qInfo() << "SettingsScriptingInterface::setValue -- allowing restricted write: " << setting << value;
+        }
+    }
     // Make a deep-copy of the string.
     // Dangling pointers can occur with QStrings that are implicitly shared from a QScriptEngine.
     QString deepCopy = QString::fromUtf16(setting.utf16());
diff --git a/interface/src/scripting/SettingsScriptingInterface.h b/interface/src/scripting/SettingsScriptingInterface.h
index 25a8b627cb..633405dcc6 100644
--- a/interface/src/scripting/SettingsScriptingInterface.h
+++ b/interface/src/scripting/SettingsScriptingInterface.h
@@ -27,7 +27,6 @@
 
 class SettingsScriptingInterface : public QObject {
     Q_OBJECT
-    SettingsScriptingInterface() { };
 public:
     static SettingsScriptingInterface* getInstance();
 
@@ -64,6 +63,16 @@ public slots:
      * print("Value: " + (typeof value) + " " + JSON.stringify(value));  // object {"x":0,"y":10,"z":0}
      */
     void setValue(const QString& setting, const QVariant& value);
+
+protected:
+    SettingsScriptingInterface(QObject* parent = nullptr) : QObject(parent) { };
+    bool _restrictPrivateValues { true };
+};
+
+class QMLSettingsScriptingInterface : public SettingsScriptingInterface {
+    Q_OBJECT
+public:
+    QMLSettingsScriptingInterface(QObject* parent) : SettingsScriptingInterface(parent) { _restrictPrivateValues = false; }
 };
 
 #endif // hifi_SettingsScriptingInterface_h