Remove user privilege elevation for ISO file writing to USB

src/CMakeLists.txt

@@ -63,14 +63,12 @@ endif()
 
 if(UNIX AND NOT APPLE)
   set(OMI_HEADERS ${OMI_HEADERS}
-                  linux/platform_lin_suprogram.h
                   linux/usbdevicemonitor_lin_p.h
   )
 
   set(OMI_SOURCES ${OMI_SOURCES}
                   linux/externalprogressbar_lin.cpp
                   linux/platform_lin.cpp
-                  linux/platform_lin_suprogram.cpp
                   linux/usbdevicemonitor_lin.cpp
   )
 
@@ -96,6 +94,11 @@ if(UNIX AND NOT APPLE)
         RENAME
           om-imagewriter.svg
   )
+
+  install(FILES ${CMAKE_SOURCE_DIR}/src/linux/udev_rules/71-usb-storage.rules
+        DESTINATION
+          lib/udev/rules.d
+  )
 endif()
 
 qt_add_executable(om-imagewriter 

src/linux/platform_lin.cpp

@@ -5,7 +5,6 @@
 #include <QDir>
 #include <QRegularExpression>
 
-#include "platform_lin_suprogram.h"
 #include "../mainapplication.h"
 #include "../usbdevice.h"
 
@@ -110,78 +109,3 @@ bool platformEnumFlashDevices(AddFlashDeviceCallbackProc callback, void* cbParam
     return true;
 }
 
-bool ensureElevated()
-{
-    // If we already have root privileges do nothing
-    uid_t uid = getuid();
-    if (uid == 0)
-        return true;
-
-    // Search for known GUI su-applications.
-    // The list is priority-ordered. If there are native su-applications present,
-    // using the first such program. Otherwise, using just the first program that is present.
-    QList<SuProgram*> suPrograms = { new XdgSu(), new BeeSu(), new KdeSu(), new GkSu() };
-    SuProgram* suProgram = NULL;
-    for (int i = 0; i < suPrograms.size(); ++i)
-    {
-        // Skip missing su-apps
-        if (!suPrograms[i]->isPresent())
-            continue;
-
-        if (suPrograms[i]->isNative())
-        {
-            // If we found a native su-application - using it as preferred and stop searching
-            suProgram = suPrograms[i];
-            break;
-        }
-        else
-        {
-            // If not native, and no other su-application was found - using it, but continue searching,
-            // in case a native app will appear down the list
-            if (suProgram == NULL)
-                suProgram = suPrograms[i];
-        }
-    }
-    if (suProgram == NULL)
-    {
-        QMessageBox::critical(
-            NULL,
-            ApplicationTitle,
-            "<font color=\"red\">" + QObject::tr("Error!") + "</font> " + QObject::tr("No appropriate su-application found!") + "<br>" +
-            QObject::tr("Please, restart the program with root privileges."),
-            QMessageBox::Ok
-        );
-        return false;
-    }
-
-    // Prepare the list of arguments and restart ourselves using the su-application found
-    QStringList args;
-    // First comes our own executable
-    args << mApp->applicationFilePath();
-    // We need to explicitly pass language and initial directory so that the new instance
-    // inherited the current user's parameters rather than root's
-    QString argLang = mApp->getLocale();
-    if (!argLang.isEmpty())
-        args << "--lang=" + argLang;
-    QString argDir = mApp->getInitialDir();
-    if (!argDir.isEmpty())
-        args << "--dir=" + argDir;
-    // Finally, if image file was supplied, append it as well
-    QString argImage = mApp->getInitialImage();
-    if (!argImage.isEmpty())
-        args << argImage;
-    // And now try to take off with all this garbage
-    suProgram->restartAsRoot(args);
-
-    // Something went wrong, we should have never returned! Cleanup and return error
-    for (int i = 0; i < suPrograms.size(); ++i)
-        delete suPrograms[i];
-    QMessageBox::critical(
-        NULL,
-        ApplicationTitle,
-        "<font color=\"red\">" + QObject::tr("Error!") + "</font> " + QObject::tr("Failed to restart with root privileges! (Error code: %1)").arg(errno) + "<br>" +
-        QObject::tr("Please, restart the program with root privileges."),
-        QMessageBox::Ok
-    );
-    return false;
-}

src/linux/udev_rules/71-usb-storage.rules

@@ -0,0 +1 @@
+KERNEL=="sd*", SUBSYSTEMS=="usb", MODE="0660", TAG+="uaccess"

src/main.cpp

@@ -38,8 +38,10 @@ int main(int argc, char *argv[])
     appTranslator.load(langName, QCoreApplication::applicationDirPath() + "/lang");
     a.installTranslator(&appTranslator);
 
+#if defined(Q_OS_MAC) || defined(Q_OS_WIN32)
     if (!ensureElevated())
         return 1;
+#endif
 
 #if defined(Q_OS_WIN32)
     // CoInitialize() seems to be called by Qt automatically, so only set security attributes

src/mainapplication.cpp

@@ -24,19 +24,14 @@ QString MainApplication::getInitialDir()
     // win:restricted
     // win:admin
     // mac:restricted
-    // linux:restricted
-    // linux:root
-    // linux: translated dir names
+    // linux: should be using udev rules with MODE="0660", TAG+="uaccess"
     // win: redefined paths
-    if (m_Options.isSet("dir"))
+    if (m_Options.isSet("dir")) {
         return m_Options.value("dir");
-
-    // Otherwise get the standard system Downloads location
-    QStringList downloadDirs = QStandardPaths::standardLocations(QStandardPaths::DownloadLocation);
-    if (downloadDirs.size() > 0)
-        return downloadDirs.at(0);
-    else
-        return "";
+    } else {
+        // Otherwise get the standard system Downloads location
+        return QStandardPaths::writableLocation(QStandardPaths::DownloadLocation);
+    }
 }
 
 // Returns the fila path passed to the application as command-line parameter