<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>association.cpp Example File | Qt Network 5.12.2</title> <link rel="stylesheet" type="text/css" href="style/offline-simple.css" /> <script type="text/javascript"> document.getElementsByTagName("link").item(0).setAttribute("href", "style/offline.css"); // loading style sheet breaks anchors that were jumped to before // so force jumping to anchor again setTimeout(function() { var anchor = location.hash; // need to jump to different anchor first (e.g. none) location.hash = "#"; setTimeout(function() { location.hash = anchor; }, 0); }, 0); </script> </head> <body> <div class="header" id="qtdocheader"> <div class="main"> <div class="main-rounded"> <div class="navigationbar"> <table><tr> <td >Qt 5.12</td><td ><a href="qtnetwork-index.html">Qt Network</a></td><td ><a href="qtnetwork-secureudpclient-example.html">DTLS client</a></td><td >association.cpp Example File</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtnetwork-index.html">Qt 5.12.2 Reference Documentation</a></td> </tr></table> </div> </div> <div class="content"> <div class="line"> <div class="content mainContent"> <div class="sidebar"><div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">association.cpp Example File</h1> <span class="subtitle">secureudpclient/association.cpp</span> <!-- $$$secureudpclient/association.cpp-description --> <div class="descr"> <a name="details"></a> <pre class="cpp"> <span class="comment">/**************************************************************************** ** ** Copyright (C) 2018 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** BSD License Usage ** Alternatively, you may use this file under the terms of the BSD license ** as follows: ** ** "Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions are ** met: ** * Redistributions of source code must retain the above copyright ** notice, this list of conditions and the following disclaimer. ** * Redistributions in binary form must reproduce the above copyright ** notice, this list of conditions and the following disclaimer in ** the documentation and/or other materials provided with the ** distribution. ** * Neither the name of The Qt Company Ltd nor the names of its ** contributors may be used to endorse or promote products derived ** from this software without specific prior written permission. ** ** ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." ** ** $QT_END_LICENSE$ ** ****************************************************************************/</span> <span class="preprocessor">#include "association.h"</span> DtlsAssociation<span class="operator">::</span>DtlsAssociation(<span class="keyword">const</span> <span class="type"><a href="qhostaddress.html">QHostAddress</a></span> <span class="operator">&</span>address<span class="operator">,</span> <span class="type"><a href="../qtcore/qtglobal.html#quint16-typedef">quint16</a></span> port<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> <span class="operator">&</span>connectionName) : name(connectionName)<span class="operator">,</span> crypto(<span class="type"><a href="qsslsocket.html">QSslSocket</a></span><span class="operator">::</span>SslClientMode) { <span class="keyword">auto</span> configuration <span class="operator">=</span> <span class="type"><a href="qsslconfiguration.html">QSslConfiguration</a></span><span class="operator">::</span>defaultDtlsConfiguration(); configuration<span class="operator">.</span>setPeerVerifyMode(<span class="type"><a href="qsslsocket.html">QSslSocket</a></span><span class="operator">::</span>VerifyNone); crypto<span class="operator">.</span>setPeer(address<span class="operator">,</span> port); crypto<span class="operator">.</span>setDtlsConfiguration(configuration); connect(<span class="operator">&</span>crypto<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qdtls.html">QDtls</a></span><span class="operator">::</span>handshakeTimeout<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>DtlsAssociation<span class="operator">::</span>handshakeTimeout); connect(<span class="operator">&</span>crypto<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qdtls.html">QDtls</a></span><span class="operator">::</span>pskRequired<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>DtlsAssociation<span class="operator">::</span>pskRequired); socket<span class="operator">.</span>connectToHost(address<span class="operator">.</span>toString()<span class="operator">,</span> port); connect(<span class="operator">&</span>socket<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qudpsocket.html">QUdpSocket</a></span><span class="operator">::</span>readyRead<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>DtlsAssociation<span class="operator">::</span>readyRead); pingTimer<span class="operator">.</span>setInterval(<span class="number">5000</span>); connect(<span class="operator">&</span>pingTimer<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="../qtcore/qtimer.html">QTimer</a></span><span class="operator">::</span>timeout<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>DtlsAssociation<span class="operator">::</span>pingTimeout); } DtlsAssociation<span class="operator">::</span><span class="operator">~</span>DtlsAssociation() { <span class="keyword">if</span> (crypto<span class="operator">.</span>isConnectionEncrypted()) crypto<span class="operator">.</span>shutdown(<span class="operator">&</span>socket); } <span class="type">void</span> DtlsAssociation<span class="operator">::</span>startHandshake() { <span class="keyword">if</span> (socket<span class="operator">.</span>state() <span class="operator">!</span><span class="operator">=</span> <span class="type"><a href="qabstractsocket.html">QAbstractSocket</a></span><span class="operator">::</span>ConnectedState) { <span class="keyword">emit</span> infoMessage(tr(<span class="string">"%1: connecting UDP socket first ..."</span>)<span class="operator">.</span>arg(name)); connect(<span class="operator">&</span>socket<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qabstractsocket.html">QAbstractSocket</a></span><span class="operator">::</span>connected<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>DtlsAssociation<span class="operator">::</span>udpSocketConnected); <span class="keyword">return</span>; } <span class="keyword">if</span> (<span class="operator">!</span>crypto<span class="operator">.</span>doHandshake(<span class="operator">&</span>socket)) <span class="keyword">emit</span> errorMessage(tr(<span class="string">"%1: failed to start a handshake - %2"</span>)<span class="operator">.</span>arg(name<span class="operator">,</span> crypto<span class="operator">.</span>dtlsErrorString())); <span class="keyword">else</span> <span class="keyword">emit</span> infoMessage(tr(<span class="string">"%1: starting a handshake"</span>)<span class="operator">.</span>arg(name)); } <span class="type">void</span> DtlsAssociation<span class="operator">::</span>udpSocketConnected() { <span class="keyword">emit</span> infoMessage(tr(<span class="string">"%1: UDP socket is now in ConnectedState, continue with handshake ..."</span>)<span class="operator">.</span>arg(name)); startHandshake(); } <span class="type">void</span> DtlsAssociation<span class="operator">::</span>readyRead() { <span class="type"><a href="../qtcore/qbytearray.html">QByteArray</a></span> dgram(socket<span class="operator">.</span>pendingDatagramSize()<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>Uninitialized); <span class="keyword">const</span> <span class="type"><a href="../qtcore/qtglobal.html#qint64-typedef">qint64</a></span> bytesRead <span class="operator">=</span> socket<span class="operator">.</span>readDatagram(dgram<span class="operator">.</span>data()<span class="operator">,</span> dgram<span class="operator">.</span>size()); <span class="keyword">if</span> (bytesRead <span class="operator"><</span><span class="operator">=</span> <span class="number">0</span>) { <span class="keyword">emit</span> warningMessage(tr(<span class="string">"%1: spurious read notification?"</span>)<span class="operator">.</span>arg(name)); <span class="keyword">return</span>; } dgram<span class="operator">.</span>resize(bytesRead); <span class="keyword">if</span> (crypto<span class="operator">.</span>isConnectionEncrypted()) { <span class="keyword">const</span> <span class="type"><a href="../qtcore/qbytearray.html">QByteArray</a></span> plainText <span class="operator">=</span> crypto<span class="operator">.</span>decryptDatagram(<span class="operator">&</span>socket<span class="operator">,</span> dgram); <span class="keyword">if</span> (plainText<span class="operator">.</span>size()) { <span class="keyword">emit</span> serverResponse(name<span class="operator">,</span> dgram<span class="operator">,</span> plainText); <span class="keyword">return</span>; } <span class="keyword">if</span> (crypto<span class="operator">.</span>dtlsError() <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="qdtls.html#QDtlsError-enum">QDtlsError</a></span><span class="operator">::</span>RemoteClosedConnectionError) { <span class="keyword">emit</span> errorMessage(tr(<span class="string">"%1: shutdown alert received"</span>)<span class="operator">.</span>arg(name)); socket<span class="operator">.</span>close(); pingTimer<span class="operator">.</span>stop(); <span class="keyword">return</span>; } <span class="keyword">emit</span> warningMessage(tr(<span class="string">"%1: zero-length datagram received?"</span>)<span class="operator">.</span>arg(name)); } <span class="keyword">else</span> { <span class="keyword">if</span> (<span class="operator">!</span>crypto<span class="operator">.</span>doHandshake(<span class="operator">&</span>socket<span class="operator">,</span> dgram)) { <span class="keyword">emit</span> errorMessage(tr(<span class="string">"%1: handshake error - %2"</span>)<span class="operator">.</span>arg(name<span class="operator">,</span> crypto<span class="operator">.</span>dtlsErrorString())); <span class="keyword">return</span>; } <span class="keyword">if</span> (crypto<span class="operator">.</span>isConnectionEncrypted()) { <span class="keyword">emit</span> infoMessage(tr(<span class="string">"%1: encrypted connection established!"</span>)<span class="operator">.</span>arg(name)); pingTimer<span class="operator">.</span>start(); pingTimeout(); } <span class="keyword">else</span> { <span class="keyword">emit</span> infoMessage(tr(<span class="string">"%1: continuing with handshake ..."</span>)<span class="operator">.</span>arg(name)); } } } <span class="type">void</span> DtlsAssociation<span class="operator">::</span>handshakeTimeout() { <span class="keyword">emit</span> warningMessage(tr(<span class="string">"%1: handshake timeout, trying to re-transmit"</span>)<span class="operator">.</span>arg(name)); <span class="keyword">if</span> (<span class="operator">!</span>crypto<span class="operator">.</span>handleTimeout(<span class="operator">&</span>socket)) <span class="keyword">emit</span> errorMessage(tr(<span class="string">"%1: failed to re-transmit - %2"</span>)<span class="operator">.</span>arg(name<span class="operator">,</span> crypto<span class="operator">.</span>dtlsErrorString())); } <span class="type">void</span> DtlsAssociation<span class="operator">::</span>pskRequired(<span class="type"><a href="qsslpresharedkeyauthenticator.html">QSslPreSharedKeyAuthenticator</a></span> <span class="operator">*</span>auth) { Q_ASSERT(auth); <span class="keyword">emit</span> infoMessage(tr(<span class="string">"%1: providing pre-shared key ..."</span>)<span class="operator">.</span>arg(name)); auth<span class="operator">-</span><span class="operator">></span>setIdentity(name<span class="operator">.</span>toLatin1()); auth<span class="operator">-</span><span class="operator">></span>setPreSharedKey(<span class="type"><a href="../qtcore/qbytearray.html#QByteArrayLiteral">QByteArrayLiteral</a></span>(<span class="string">"\x1a\x2b\x3c\x4d\x5e\x6f"</span>)); } <span class="type">void</span> DtlsAssociation<span class="operator">::</span>pingTimeout() { <span class="keyword">static</span> <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> message <span class="operator">=</span> <span class="type"><a href="../qtcore/qstring.html#QStringLiteral">QStringLiteral</a></span>(<span class="string">"I am %1, please, accept our ping %2"</span>); <span class="keyword">const</span> <span class="type"><a href="../qtcore/qtglobal.html#qint64-typedef">qint64</a></span> written <span class="operator">=</span> crypto<span class="operator">.</span>writeDatagramEncrypted(<span class="operator">&</span>socket<span class="operator">,</span> message<span class="operator">.</span>arg(name)<span class="operator">.</span>arg(ping)<span class="operator">.</span>toLatin1()); <span class="keyword">if</span> (written <span class="operator"><</span><span class="operator">=</span> <span class="number">0</span>) { <span class="keyword">emit</span> errorMessage(tr(<span class="string">"%1: failed to send a ping - %2"</span>)<span class="operator">.</span>arg(name<span class="operator">,</span> crypto<span class="operator">.</span>dtlsErrorString())); pingTimer<span class="operator">.</span>stop(); <span class="keyword">return</span>; } <span class="operator">+</span><span class="operator">+</span>ping; } </pre> </div> <!-- @@@secureudpclient/association.cpp --> </div> </div> </div> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2019 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners.<br/> The documentation provided herein is licensed under the terms of the <a href="http://www.gnu.org/licenses/fdl.html">GNU Free Documentation License version 1.3</a> as published by the Free Software Foundation.<br/> Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners. </p> </div> </body> </html>