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| |
| #include "association.h" |
| |
| QT_BEGIN_NAMESPACE |
| |
| DtlsAssociation::DtlsAssociation(const QHostAddress &address, quint16 port, |
| const QString &connectionName) |
| : name(connectionName), |
| crypto(QSslSocket::SslClientMode) |
| { |
| //! [1] |
| auto configuration = QSslConfiguration::defaultDtlsConfiguration(); |
| configuration.setPeerVerifyMode(QSslSocket::VerifyNone); |
| crypto.setPeer(address, port); |
| crypto.setDtlsConfiguration(configuration); |
| //! [1] |
| |
| //! [2] |
| connect(&crypto, &QDtls::handshakeTimeout, this, &DtlsAssociation::handshakeTimeout); |
| //! [2] |
| connect(&crypto, &QDtls::pskRequired, this, &DtlsAssociation::pskRequired); |
| //! [3] |
| socket.connectToHost(address.toString(), port); |
| //! [3] |
| //! [13] |
| connect(&socket, &QUdpSocket::readyRead, this, &DtlsAssociation::readyRead); |
| //! [13] |
| //! [4] |
| pingTimer.setInterval(5000); |
| connect(&pingTimer, &QTimer::timeout, this, &DtlsAssociation::pingTimeout); |
| //! [4] |
| } |
| |
| //! [12] |
| DtlsAssociation::~DtlsAssociation() |
| { |
| if (crypto.isConnectionEncrypted()) |
| crypto.shutdown(&socket); |
| } |
| //! [12] |
| |
| //! [5] |
| void DtlsAssociation::startHandshake() |
| { |
| if (socket.state() != QAbstractSocket::ConnectedState) { |
| emit infoMessage(tr("%1: connecting UDP socket first ...").arg(name)); |
| connect(&socket, &QAbstractSocket::connected, this, &DtlsAssociation::udpSocketConnected); |
| return; |
| } |
| |
| if (!crypto.doHandshake(&socket)) |
| emit errorMessage(tr("%1: failed to start a handshake - %2").arg(name, crypto.dtlsErrorString())); |
| else |
| emit infoMessage(tr("%1: starting a handshake").arg(name)); |
| } |
| //! [5] |
| |
| void DtlsAssociation::udpSocketConnected() |
| { |
| emit infoMessage(tr("%1: UDP socket is now in ConnectedState, continue with handshake ...").arg(name)); |
| startHandshake(); |
| } |
| |
| void DtlsAssociation::readyRead() |
| { |
| //! [6] |
| QByteArray dgram(socket.pendingDatagramSize(), Qt::Uninitialized); |
| const qint64 bytesRead = socket.readDatagram(dgram.data(), dgram.size()); |
| if (bytesRead <= 0) { |
| emit warningMessage(tr("%1: spurious read notification?").arg(name)); |
| return; |
| } |
| |
| dgram.resize(bytesRead); |
| //! [6] |
| //! [7] |
| if (crypto.isConnectionEncrypted()) { |
| const QByteArray plainText = crypto.decryptDatagram(&socket, dgram); |
| if (plainText.size()) { |
| emit serverResponse(name, dgram, plainText); |
| return; |
| } |
| |
| if (crypto.dtlsError() == QDtlsError::RemoteClosedConnectionError) { |
| emit errorMessage(tr("%1: shutdown alert received").arg(name)); |
| socket.close(); |
| pingTimer.stop(); |
| return; |
| } |
| |
| emit warningMessage(tr("%1: zero-length datagram received?").arg(name)); |
| } else { |
| //! [7] |
| //! [8] |
| if (!crypto.doHandshake(&socket, dgram)) { |
| emit errorMessage(tr("%1: handshake error - %2").arg(name, crypto.dtlsErrorString())); |
| return; |
| } |
| //! [8] |
| |
| //! [9] |
| if (crypto.isConnectionEncrypted()) { |
| emit infoMessage(tr("%1: encrypted connection established!").arg(name)); |
| pingTimer.start(); |
| pingTimeout(); |
| } else { |
| //! [9] |
| emit infoMessage(tr("%1: continuing with handshake ...").arg(name)); |
| } |
| } |
| } |
| |
| //! [11] |
| void DtlsAssociation::handshakeTimeout() |
| { |
| emit warningMessage(tr("%1: handshake timeout, trying to re-transmit").arg(name)); |
| if (!crypto.handleTimeout(&socket)) |
| emit errorMessage(tr("%1: failed to re-transmit - %2").arg(name, crypto.dtlsErrorString())); |
| } |
| //! [11] |
| |
| //! [14] |
| void DtlsAssociation::pskRequired(QSslPreSharedKeyAuthenticator *auth) |
| { |
| Q_ASSERT(auth); |
| |
| emit infoMessage(tr("%1: providing pre-shared key ...").arg(name)); |
| auth->setIdentity(name.toLatin1()); |
| auth->setPreSharedKey(QByteArrayLiteral("\x1a\x2b\x3c\x4d\x5e\x6f")); |
| } |
| //! [14] |
| |
| //! [10] |
| void DtlsAssociation::pingTimeout() |
| { |
| static const QString message = QStringLiteral("I am %1, please, accept our ping %2"); |
| const qint64 written = crypto.writeDatagramEncrypted(&socket, message.arg(name).arg(ping).toLatin1()); |
| if (written <= 0) { |
| emit errorMessage(tr("%1: failed to send a ping - %2").arg(name, crypto.dtlsErrorString())); |
| pingTimer.stop(); |
| return; |
| } |
| |
| ++ping; |
| } |
| //! [10] |
| |
| QT_END_NAMESPACE |