WireGuard for MacOS (#248)

* WireGuard for MacOS
* Fix openvpn block-outside-dns

client/mozilla/pingsender.h

@@ -0,0 +1,31 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef PINGSENDER_H
+#define PINGSENDER_H
+
+#include <QElapsedTimer>
+#include <QHostAddress>
+#include <QObject>
+
+class PingSender : public QObject {
+  Q_OBJECT
+  Q_DISABLE_COPY_MOVE(PingSender)
+
+ public:
+  PingSender(QObject* parent = nullptr) : QObject(parent) {}
+  virtual ~PingSender() = default;
+
+  virtual bool isValid() { return true; };
+
+  virtual void sendPing(const QHostAddress& destination, quint16 sequence) = 0;
+
+  static quint16 inetChecksum(const void* data, size_t length);
+
+ signals:
+  void recvPing(quint16 sequence);
+  void criticalPingError();
+};
+
+#endif  // PINGSENDER_H