chore: updates from proxy-storage-cache branch

CMakeLists.txt

@@ -4,7 +4,7 @@ set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
 set(PROJECT AmneziaVPN)
-set(AMNEZIAVPN_VERSION 4.9.0.2)
+set(AMNEZIAVPN_VERSION 4.9.0.3)
 
 set(QT_CREATOR_SKIP_PACKAGE_MANAGER_SETUP ON CACHE BOOL "" FORCE)
 set(CMAKE_PROJECT_TOP_LEVEL_INCLUDES
@@ -28,7 +28,7 @@ string(TIMESTAMP CURRENT_DATE "%Y-%m-%d")
 set(RELEASE_DATE "${CURRENT_DATE}")
 
 set(APP_MAJOR_VERSION ${CMAKE_PROJECT_VERSION_MAJOR}.${CMAKE_PROJECT_VERSION_MINOR}.${CMAKE_PROJECT_VERSION_PATCH})
-set(APP_ANDROID_VERSION_CODE 2123)
+set(APP_ANDROID_VERSION_CODE 2126)
 
 if(${CMAKE_SYSTEM_NAME} STREQUAL "Linux")
     set(MZ_PLATFORM_NAME "linux")

client/android/src/org/amnezia/vpn/AmneziaActivity.kt

@@ -789,6 +789,16 @@ class AmneziaActivity : QtActivity() {
                             else -> type = "*/*"
                         }
                     }
+                    // Force system document picker to avoid third-party file managers
+                    // that may lack storage permissions (common on Android TV devices)
+                    val systemPickerPackage = listOf("com.google.android.documentsui", "com.android.documentsui")
+                        .firstOrNull { pkg ->
+                            try { packageManager.getPackageInfo(pkg, 0); true }
+                            catch (_: PackageManager.NameNotFoundException) { false }
+                        }
+                    if (systemPickerPackage != null) {
+                        `package` = systemPickerPackage
+                    }
                 }
             } else {
                 Intent(this@AmneziaActivity, TvFilePicker::class.java)
@@ -1061,12 +1071,10 @@ class AmneziaActivity : QtActivity() {
     @Suppress("unused")
     fun sendTouch(x: Float, y: Float) {
         Log.v(TAG, "Send touch: $x, $y")
-        blockingCall {
-            findQtWindow(window.decorView)?.let {
-                Log.v(TAG, "Send touch to $it")
-                it.dispatchTouchEvent(createEvent(x, y, SystemClock.uptimeMillis(), MotionEvent.ACTION_DOWN))
-                it.dispatchTouchEvent(createEvent(x, y, SystemClock.uptimeMillis(), MotionEvent.ACTION_UP))
-            }
+        findQtWindow(window.decorView)?.let {
+            Log.v(TAG, "Send touch to $it")
+            it.dispatchTouchEvent(createEvent(x, y, SystemClock.uptimeMillis(), MotionEvent.ACTION_DOWN))
+            it.dispatchTouchEvent(createEvent(x, y, SystemClock.uptimeMillis(), MotionEvent.ACTION_UP))
         }
     }
 

client/core/controllers/api/newsController.cpp

@@ -78,7 +78,8 @@ QFuture<QPair<ErrorCode, QJsonArray>> NewsController::fetchNews()
             m_appSettingsRepository->getGatewayEndpoint(),
             m_appSettingsRepository->isDevGatewayEnv(),
             apiDefs::requestTimeoutMsecs,
-            m_appSettingsRepository->isStrictKillSwitchEnabled());
+            m_appSettingsRepository->isStrictKillSwitchEnabled(),
+            m_appSettingsRepository);
 
     QJsonObject payload;
     payload.insert("locale", m_appSettingsRepository->getAppLanguage().name().split("_").first());

client/core/controllers/api/servicesCatalogController.cpp

@@ -242,7 +242,7 @@ ErrorCode ServicesCatalogController::fillAvailableServices(QJsonObject &services
 ErrorCode ServicesCatalogController::executeRequest(const QString &endpoint, const QJsonObject &apiPayload, QByteArray &responseBody)
 {
     GatewayController gatewayController(m_appSettingsRepository->getGatewayEndpoint(), m_appSettingsRepository->isDevGatewayEnv(), apiDefs::requestTimeoutMsecs,
-                                        m_appSettingsRepository->isStrictKillSwitchEnabled());
+                                        m_appSettingsRepository->isStrictKillSwitchEnabled(), m_appSettingsRepository);
     return gatewayController.post(endpoint, apiPayload, responseBody);
 }
 

client/core/controllers/api/subscriptionController.cpp

@@ -212,7 +212,7 @@ void SubscriptionController::updateApiConfigInJson(QJsonObject &serverConfigJson
 ErrorCode SubscriptionController::executeRequest(const QString &endpoint, const QJsonObject &apiPayload, QByteArray &responseBody, bool isTestPurchase)
 {
     GatewayController gatewayController(m_appSettingsRepository->getGatewayEndpoint(isTestPurchase), m_appSettingsRepository->isDevGatewayEnv(isTestPurchase), apiDefs::requestTimeoutMsecs,
-                                        m_appSettingsRepository->isStrictKillSwitchEnabled());
+                                        m_appSettingsRepository->isStrictKillSwitchEnabled(), m_appSettingsRepository);
     return gatewayController.post(endpoint, apiPayload, responseBody);
 }
 
@@ -949,7 +949,8 @@ QFuture<QPair<ErrorCode, QString>> SubscriptionController::getRenewalLink(const
     auto gatewayController = QSharedPointer<GatewayController>::create(m_appSettingsRepository->getGatewayEndpoint(isTestPurchase),
                                                                        m_appSettingsRepository->isDevGatewayEnv(isTestPurchase),
                                                                        apiDefs::requestTimeoutMsecs,
-                                                                       m_appSettingsRepository->isStrictKillSwitchEnabled());
+                                                                       m_appSettingsRepository->isStrictKillSwitchEnabled(),
+                                                                       m_appSettingsRepository);
     auto postFuture = gatewayController->postAsync(QString("%1v1/renewal_link"), apiPayload);
     auto *watcher = new QFutureWatcher<QPair<ErrorCode, QByteArray>>();
     QObject::connect(watcher, &QFutureWatcher<QPair<ErrorCode, QByteArray>>::finished,

client/core/controllers/gatewayController.cpp

@@ -16,6 +16,7 @@
 #include "QRsa.h"
 
 #include "amneziaApplication.h"
+#include "core/repositories/secureAppSettingsRepository.h"
 #include "core/utils/api/apiUtils.h"
 #include "core/utils/constants/apiKeys.h"
 #include "core/utils/networkUtilities.h"
@@ -45,15 +46,78 @@ namespace
     constexpr QLatin1String unprocessableSubscriptionMessage("Failed to retrieve subscription information. Is it activated?");
 
     constexpr int proxyStorageRequestTimeoutMsecs = 3000;
+
+    QStringList shuffledProxyUrls(const QStringList &proxyUrls)
+    {
+        QStringList shuffled = proxyUrls;
+        std::random_device randomDevice;
+        std::mt19937 generator(randomDevice());
+        std::shuffle(shuffled.begin(), shuffled.end(), generator);
+        return shuffled;
+    }
+
+    QString getProxyUrlsCacheKey(const QString &serviceType, const QString &userCountryCode)
+    {
+        return QStringLiteral("service_%1_country_%2").arg(serviceType, userCountryCode);
+    }
+
+    bool decryptProxyUrlsPayload(const QByteArray &encryptedPayload, bool isDevEnvironment, QByteArray &decryptedPayload)
+    {
+        try {
+            QByteArray key = isDevEnvironment ? DEV_AGW_PUBLIC_KEY : PROD_AGW_PUBLIC_KEY;
+            if (!isDevEnvironment) {
+                QCryptographicHash hash(QCryptographicHash::Sha512);
+                hash.addData(key);
+                QByteArray h = hash.result().toHex();
+
+                QByteArray decKey = QByteArray::fromHex(h.left(64));
+                QByteArray iv = QByteArray::fromHex(h.mid(64, 32));
+                QByteArray ba = QByteArray::fromBase64(encryptedPayload);
+
+                QSimpleCrypto::QBlockCipher cipher;
+                decryptedPayload = cipher.decryptAesBlockCipher(ba, decKey, iv);
+            } else {
+                decryptedPayload = encryptedPayload;
+            }
+            return true;
+        } catch (...) {
+            Utils::logException();
+            return false;
+        }
+    }
+
+    QStringList readCachedProxyUrls(const QByteArray &cachedProxyUrlsEncrypted, bool isDevEnvironment)
+    {
+        if (cachedProxyUrlsEncrypted.isEmpty()) {
+            return {};
+        }
+
+        QByteArray cachedProxyUrlsDecrypted;
+        if (!decryptProxyUrlsPayload(cachedProxyUrlsEncrypted, isDevEnvironment, cachedProxyUrlsDecrypted)) {
+            qCritical() << "error decrypting cached proxy urls payload";
+            return {};
+        }
+
+        QJsonArray endpointsArray = QJsonDocument::fromJson(cachedProxyUrlsDecrypted).array();
+        QStringList endpoints;
+        endpoints.reserve(endpointsArray.size());
+        for (const QJsonValue &endpoint : endpointsArray) {
+            endpoints.push_back(endpoint.toString());
+        }
+
+        return endpoints;
+    }
 }
 
 GatewayController::GatewayController(const QString &gatewayEndpoint, const bool isDevEnvironment, const int requestTimeoutMsecs,
-                                     const bool isStrictKillSwitchEnabled, QObject *parent)
+                                     const bool isStrictKillSwitchEnabled, SecureAppSettingsRepository *appSettingsRepository,
+                                     QObject *parent)
     : QObject(parent),
       m_gatewayEndpoint(gatewayEndpoint),
       m_isDevEnvironment(isDevEnvironment),
       m_requestTimeoutMsecs(requestTimeoutMsecs),
-      m_isStrictKillSwitchEnabled(isStrictKillSwitchEnabled)
+      m_isStrictKillSwitchEnabled(isStrictKillSwitchEnabled),
+      m_appSettingsRepository(appSettingsRepository)
 {
 }
 
@@ -308,8 +372,9 @@ QFuture<QPair<ErrorCode, QByteArray>> GatewayController::postAsync(const QString
             QStringList proxyStorageUrls;
             appendStorageUrls(primaryBaseUrls, proxyStorageUrls);
             appendStorageUrls(fallbackBaseUrls, proxyStorageUrls);
+            const QString proxyUrlsCacheKey = getProxyUrlsCacheKey(serviceType, userCountryCode);
 
-            getProxyUrlsAsync(proxyStorageUrls, 0, [this, encRequestData, endpoint, processResponse](const QStringList &proxyUrls) {
+            getProxyUrlsAsync(proxyStorageUrls, 0, proxyUrlsCacheKey, [this, encRequestData, endpoint, processResponse](const QStringList &proxyUrls) {
                 getProxyUrlAsync(proxyUrls, 0, [this, encRequestData, endpoint, processResponse](const QString &proxyUrl) {
                     bypassProxyAsync(endpoint, proxyUrl, encRequestData,
                                      [processResponse, this](const QByteArray &decryptedBody, bool isDecryptionSuccessful,
@@ -355,8 +420,6 @@ QStringList GatewayController::getProxyUrls(const QString &serviceType, const QS
     std::shuffle(primaryBaseUrls.begin(), primaryBaseUrls.end(), generator);
     std::shuffle(fallbackBaseUrls.begin(), fallbackBaseUrls.end(), generator);
 
-    QByteArray key = m_isDevEnvironment ? DEV_AGW_PUBLIC_KEY : PROD_AGW_PUBLIC_KEY;
-
     auto appendStorageUrls = [&serviceType, &userCountryCode](const QStringList &baseUrls, QStringList &target) {
         if (!serviceType.isEmpty()) {
             for (const auto &baseUrl : baseUrls) {
@@ -372,10 +435,12 @@ QStringList GatewayController::getProxyUrls(const QString &serviceType, const QS
     QStringList proxyStorageUrls;
     appendStorageUrls(primaryBaseUrls, proxyStorageUrls);
     appendStorageUrls(fallbackBaseUrls, proxyStorageUrls);
+    const QString proxyUrlsCacheKey = getProxyUrlsCacheKey(serviceType, userCountryCode);
+    const QByteArray cachedProxyUrlsEncrypted = m_appSettingsRepository->readGatewayProxyUrls(proxyUrlsCacheKey);
 
     if (proxyStorageUrls.empty()) {
         qDebug() << "empty storage endpoint list";
-        return {};
+        return readCachedProxyUrls(cachedProxyUrlsEncrypted, m_isDevEnvironment);
     }
 
     for (const auto &proxyStorageUrl : proxyStorageUrls) {
@@ -390,26 +455,8 @@ QStringList GatewayController::getProxyUrls(const QString &serviceType, const QS
             auto encryptedResponseBody = reply->readAll();
             reply->deleteLater();
 
-            EVP_PKEY *privateKey = nullptr;
             QByteArray responseBody;
-            try {
-                if (!m_isDevEnvironment) {
-                    QCryptographicHash hash(QCryptographicHash::Sha512);
-                    hash.addData(key);
-                    QByteArray hashResult = hash.result().toHex();
-
-                    QByteArray key = QByteArray::fromHex(hashResult.left(64));
-                    QByteArray iv = QByteArray::fromHex(hashResult.mid(64, 32));
-
-                    QByteArray ba = QByteArray::fromBase64(encryptedResponseBody);
-
-                    QSimpleCrypto::QBlockCipher blockCipher;
-                    responseBody = blockCipher.decryptAesBlockCipher(ba, key, iv);
-                } else {
-                    responseBody = encryptedResponseBody;
-                }
-            } catch (...) {
-                Utils::logException();
+            if (!decryptProxyUrlsPayload(encryptedResponseBody, m_isDevEnvironment, responseBody)) {
                 qCritical() << "error loading private key from environment variables or decrypting payload" << encryptedResponseBody;
                 continue;
             }
@@ -420,6 +467,8 @@ QStringList GatewayController::getProxyUrls(const QString &serviceType, const QS
             for (const auto &endpoint : endpointsArray) {
                 endpoints.push_back(endpoint.toString());
             }
+            m_appSettingsRepository->writeGatewayProxyUrls(proxyUrlsCacheKey, encryptedResponseBody);
+
             return endpoints;
         } else {
             auto replyError = reply->error();
@@ -431,7 +480,7 @@ QStringList GatewayController::getProxyUrls(const QString &serviceType, const QS
             reply->deleteLater();
         }
     }
-    return {};
+    return readCachedProxyUrls(cachedProxyUrlsEncrypted, m_isDevEnvironment);
 }
 
 bool GatewayController::shouldBypassProxy(const QNetworkReply::NetworkError &replyError, const QByteArray &decryptedResponseBody,
@@ -573,10 +622,12 @@ void GatewayController::bypassProxy(const QString &endpoint, const QString &serv
 }
 
 void GatewayController::getProxyUrlsAsync(const QStringList proxyStorageUrls, const int currentProxyStorageIndex,
-                                          std::function<void(const QStringList &)> onComplete)
+                                          const QString &proxyUrlsCacheKey, std::function<void(const QStringList &)> onComplete)
 {
+    const QByteArray cachedProxyUrlsEncrypted = m_appSettingsRepository->readGatewayProxyUrls(proxyUrlsCacheKey);
+
     if (currentProxyStorageIndex >= proxyStorageUrls.size()) {
-        onComplete({});
+        onComplete(shuffledProxyUrls(readCachedProxyUrls(cachedProxyUrlsEncrypted, m_isDevEnvironment)));
         return;
     }
 
@@ -589,33 +640,17 @@ void GatewayController::getProxyUrlsAsync(const QStringList proxyStorageUrls, co
 
     // connect(reply, &QNetworkReply::sslErrors, this, [state](const QList<QSslError> &e) { *(state->sslErrors) = e; });
 
-    connect(reply, &QNetworkReply::finished, this, [this, proxyStorageUrls, currentProxyStorageIndex, onComplete, reply]() {
+    connect(reply, &QNetworkReply::finished, this,
+            [this, proxyStorageUrls, currentProxyStorageIndex, proxyUrlsCacheKey, onComplete, reply]() {
         if (reply->error() == QNetworkReply::NoError) {
             QByteArray encrypted = reply->readAll();
             reply->deleteLater();
 
             QByteArray responseBody;
-            try {
-                QByteArray key = m_isDevEnvironment ? DEV_AGW_PUBLIC_KEY : PROD_AGW_PUBLIC_KEY;
-                if (!m_isDevEnvironment) {
-                    QCryptographicHash hash(QCryptographicHash::Sha512);
-                    hash.addData(key);
-                    QByteArray h = hash.result().toHex();
-
-                    QByteArray decKey = QByteArray::fromHex(h.left(64));
-                    QByteArray iv = QByteArray::fromHex(h.mid(64, 32));
-                    QByteArray ba = QByteArray::fromBase64(encrypted);
-
-                    QSimpleCrypto::QBlockCipher cipher;
-                    responseBody = cipher.decryptAesBlockCipher(ba, decKey, iv);
-                } else {
-                    responseBody = encrypted;
-                }
-            } catch (...) {
-                Utils::logException();
+            if (!decryptProxyUrlsPayload(encrypted, m_isDevEnvironment, responseBody)) {
                 qCritical() << "error decrypting payload";
                 QMetaObject::invokeMethod(
-                        this, [=]() { getProxyUrlsAsync(proxyStorageUrls, currentProxyStorageIndex + 1, onComplete); }, Qt::QueuedConnection);
+                        this, [=]() { getProxyUrlsAsync(proxyStorageUrls, currentProxyStorageIndex + 1, proxyUrlsCacheKey, onComplete); }, Qt::QueuedConnection);
                 return;
             }
 
@@ -623,13 +658,9 @@ void GatewayController::getProxyUrlsAsync(const QStringList proxyStorageUrls, co
             QStringList endpoints;
             for (const QJsonValue &endpoint : endpointsArray)
                 endpoints.push_back(endpoint.toString());
+            m_appSettingsRepository->writeGatewayProxyUrls(proxyUrlsCacheKey, encrypted);
 
-            QStringList shuffled = endpoints;
-            std::random_device randomDevice;
-            std::mt19937 generator(randomDevice());
-            std::shuffle(shuffled.begin(), shuffled.end(), generator);
-
-            onComplete(shuffled);
+            onComplete(shuffledProxyUrls(endpoints));
             return;
         }
 
@@ -638,7 +669,7 @@ void GatewayController::getProxyUrlsAsync(const QStringList proxyStorageUrls, co
         qDebug() << "go to the next storage endpoint";
         reply->deleteLater();
         QMetaObject::invokeMethod(
-                this, [=]() { getProxyUrlsAsync(proxyStorageUrls, currentProxyStorageIndex + 1, onComplete); }, Qt::QueuedConnection);
+                this, [=]() { getProxyUrlsAsync(proxyStorageUrls, currentProxyStorageIndex + 1, proxyUrlsCacheKey, onComplete); }, Qt::QueuedConnection);
     });
 }
 

client/core/controllers/gatewayController.h

@@ -16,13 +16,16 @@
     #include "platforms/ios/ios_controller.h"
 #endif
 
+class SecureAppSettingsRepository;
+
 class GatewayController : public QObject
 {
     Q_OBJECT
 
 public:
     explicit GatewayController(const QString &gatewayEndpoint, const bool isDevEnvironment, const int requestTimeoutMsecs,
-                               const bool isStrictKillSwitchEnabled, QObject *parent = nullptr);
+                               const bool isStrictKillSwitchEnabled, SecureAppSettingsRepository *appSettingsRepository,
+                               QObject *parent = nullptr);
 
     amnezia::ErrorCode post(const QString &endpoint, const QJsonObject apiPayload, QByteArray &responseBody);
     QFuture<QPair<amnezia::ErrorCode, QByteArray>> postAsync(const QString &endpoint, const QJsonObject apiPayload);
@@ -55,7 +58,7 @@ private:
                      std::function<bool(QNetworkReply *reply, const QList<QSslError> &sslErrors)> replyProcessingFunction);
 
     void getProxyUrlsAsync(const QStringList proxyStorageUrls, const int currentProxyStorageIndex,
-                           std::function<void(const QStringList &)> onComplete);
+                           const QString &proxyUrlsCacheKey, std::function<void(const QStringList &)> onComplete);
     void getProxyUrlAsync(const QStringList proxyUrls, const int currentProxyIndex, std::function<void(const QString &)> onComplete);
     void bypassProxyAsync(
             const QString &endpoint, const QString &proxyUrl, EncryptedRequestData encRequestData,
@@ -65,6 +68,7 @@ private:
     QString m_gatewayEndpoint;
     bool m_isDevEnvironment = false;
     bool m_isStrictKillSwitchEnabled = false;
+    SecureAppSettingsRepository *m_appSettingsRepository = nullptr;
 
     inline static QString m_proxyUrl;
 };

client/core/controllers/updateController.cpp

@@ -95,7 +95,8 @@ void UpdateController::fetchGatewayUrl()
     auto gatewayController = QSharedPointer<GatewayController>::create(m_appSettingsRepository->getGatewayEndpoint(),
                                                                        m_appSettingsRepository->isDevGatewayEnv(),
                                                                        7000,
-                                                                       m_appSettingsRepository->isStrictKillSwitchEnabled());
+                                                                       m_appSettingsRepository->isStrictKillSwitchEnabled(),
+                                                                       m_appSettingsRepository);
 
     QJsonObject apiPayload;
     apiPayload[apiDefs::key::cliVersion] = QString(APP_VERSION);

client/core/repositories/secureAppSettingsRepository.cpp

@@ -280,6 +280,24 @@ void SecureAppSettingsRepository::toggleDevGatewayEnv(bool enabled)
     setValue("Conf/devGatewayEnv", enabled);
 }
 
+QByteArray SecureAppSettingsRepository::readGatewayProxyUrls(const QString &cacheKey) const
+{
+    if (cacheKey.isEmpty()) {
+        return {};
+    }
+
+    return value(QStringLiteral("Conf/proxyUrls/") + cacheKey).toByteArray();
+}
+
+void SecureAppSettingsRepository::writeGatewayProxyUrls(const QString &cacheKey, const QByteArray &proxyUrlsEncrypted)
+{
+    if (cacheKey.isEmpty()) {
+        return;
+    }
+
+    setValue(QStringLiteral("Conf/proxyUrls/") + cacheKey, proxyUrlsEncrypted);
+}
+
 bool SecureAppSettingsRepository::isKillSwitchEnabled() const
 {
     return value("Conf/killSwitchEnabled", true).toBool();

client/core/repositories/secureAppSettingsRepository.h

@@ -59,7 +59,9 @@ public:
     void setDevGatewayEndpoint();
     bool isDevGatewayEnv(bool isTestPurchase = false) const;
     void toggleDevGatewayEnv(bool enabled);
-    
+    QByteArray readGatewayProxyUrls(const QString &cacheKey) const;
+    void writeGatewayProxyUrls(const QString &cacheKey, const QByteArray &proxyUrlsEncrypted);
+
     bool isKillSwitchEnabled() const;
     void setKillSwitchEnabled(bool enabled);
     bool isStrictKillSwitchEnabled() const;

client/daemon/daemon.cpp

@@ -390,55 +390,55 @@ bool Daemon::parseConfig(const QJsonObject& obj, InterfaceConfig& config) {
 
   config.m_killSwitchEnabled = QVariant(obj.value("killSwitchOption").toString()).toBool();
 
-  if (!obj.value("Jc").isNull()) {
-    config.m_junkPacketCount = obj.value("Jc").toString();
+  if (const auto jc = obj.value("Jc"); !jc.isUndefined()) {
+    config.m_junkPacketCount = jc.toString();
   }
-  if (!obj.value("Jmin").isNull()) {
-    config.m_junkPacketMinSize = obj.value("Jmin").toString();
+  if (const auto jmin = obj.value("Jmin"); !jmin.isUndefined()) {
+    config.m_junkPacketMinSize = jmin.toString();
   }
-  if (!obj.value("Jmax").isNull()) {
-    config.m_junkPacketMaxSize = obj.value("Jmax").toString();
+  if (const auto jmax = obj.value("Jmax"); !jmax.isUndefined()) {
+    config.m_junkPacketMaxSize = jmax.toString();
   }
-  if (!obj.value("S1").isNull()) {
-    config.m_initPacketJunkSize = obj.value("S1").toString();
+  if (const auto s1 = obj.value("S1"); !s1.isUndefined()) {
+    config.m_initPacketJunkSize = s1.toString();
   }
-  if (!obj.value("S2").isNull()) {
-    config.m_responsePacketJunkSize = obj.value("S2").toString();
+  if (const auto s2 = obj.value("S2"); !s2.isUndefined()) {
+    config.m_responsePacketJunkSize = s2.toString();
   }
-  if (!obj.value("S3").isNull()) {
-    config.m_cookieReplyPacketJunkSize = obj.value("S3").toString();
+  if (const auto s3 = obj.value("S3"); !s3.isUndefined()) {
+    config.m_cookieReplyPacketJunkSize = s3.toString();
   }
-  if (!obj.value("S4").isNull()) {
-    config.m_transportPacketJunkSize = obj.value("S4").toString();
+  if (const auto s4 = obj.value("S4"); !s4.isUndefined()) {
+    config.m_transportPacketJunkSize = s4.toString();
   }
 
-  if (!obj.value("H1").isNull()) {
-    config.m_initPacketMagicHeader = obj.value("H1").toString();
+  if (const auto h1 = obj.value("H1"); !h1.isUndefined()) {
+    config.m_initPacketMagicHeader = h1.toString();
   }
-  if (!obj.value("H2").isNull()) {
-    config.m_responsePacketMagicHeader = obj.value("H2").toString();
+  if (const auto h2 = obj.value("H2"); !h2.isUndefined()) {
+    config.m_responsePacketMagicHeader = h2.toString();
   }
-  if (!obj.value("H3").isNull()) {
-    config.m_underloadPacketMagicHeader = obj.value("H3").toString();
+  if (const auto h3 = obj.value("H3"); !h3.isUndefined()) {
+    config.m_underloadPacketMagicHeader = h3.toString();
   }
-  if (!obj.value("H4").isNull()) {
-    config.m_transportPacketMagicHeader = obj.value("H4").toString();
+  if (const auto h4 = obj.value("H4"); !h4.isUndefined()) {
+    config.m_transportPacketMagicHeader = h4.toString();
   }
 
-  if (!obj.value("I1").isNull()) {
-    config.m_specialJunk["I1"] = obj.value("I1").toString();
+  if (const auto i1 = obj.value("I1"); !i1.isUndefined()) {
+    config.m_specialJunk["I1"] = i1.toString();
   }
-  if (!obj.value("I2").isNull()) {
-    config.m_specialJunk["I2"] = obj.value("I2").toString();
+  if (const auto i2 = obj.value("I2"); !i2.isUndefined()) {
+    config.m_specialJunk["I2"] = i2.toString();
   }
-  if (!obj.value("I3").isNull()) {
-    config.m_specialJunk["I3"] = obj.value("I3").toString();
+  if (const auto i3 = obj.value("I3"); !i3.isUndefined()) {
+    config.m_specialJunk["I3"] = i3.toString();
   }
-  if (!obj.value("I4").isNull()) {
-    config.m_specialJunk["I4"] = obj.value("I4").toString();
+  if (const auto i4 = obj.value("I4"); !i4.isUndefined()) {
+    config.m_specialJunk["I4"] = i4.toString();
   }
-  if (!obj.value("I5").isNull()) {
-    config.m_specialJunk["I5"] = obj.value("I5").toString();
+  if (const auto i5 = obj.value("I5"); !i5.isUndefined()) {
+    config.m_specialJunk["I5"] = i5.toString();
   }
 
   return true;