sslclient.cpp Example File

securesocketclient/sslclient.cpp

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  #include "certificateinfo.h"
  #include "sslclient.h"

  #include "ui_sslclient.h"
  #include "ui_sslerrors.h"

  #include <QtCore>

  SslClient::SslClient(QWidget *parent)
      : QWidget(parent)
  {
      setupUi();
      setupSecureSocket();
  }

  SslClient::~SslClient()
  {
      delete form;
  }

  void SslClient::updateEnabledState()
  {
      const bool unconnected = socket->state() == QAbstractSocket::UnconnectedState;
      form->hostNameEdit->setReadOnly(!unconnected);
      form->hostNameEdit->setFocusPolicy(unconnected ? Qt::StrongFocus : Qt::NoFocus);
      form->hostNameLabel->setEnabled(unconnected);
      form->portBox->setEnabled(unconnected);
      form->portLabel->setEnabled(unconnected);
      form->connectButton->setEnabled(unconnected && !form->hostNameEdit->text().isEmpty());

      const bool connected = socket->state() == QAbstractSocket::ConnectedState;
      form->sessionOutput->setEnabled(connected);
      form->sessionInput->setEnabled(connected);
      form->sessionInputLabel->setEnabled(connected);
      form->sendButton->setEnabled(connected);
  }

  void SslClient::secureConnect()
  {
      socket->connectToHostEncrypted(form->hostNameEdit->text(), form->portBox->value());
      updateEnabledState();
  }

  void SslClient::socketStateChanged(QAbstractSocket::SocketState state)
  {
      if (executingDialog)
          return;

      updateEnabledState();

      if (state == QAbstractSocket::UnconnectedState) {
          form->sessionInput->clear();
          form->hostNameEdit->setPalette(QPalette());
          form->hostNameEdit->setFocus();
          form->cipherLabel->setText(tr("<none>"));
          padLock->hide();
      }
  }

  void SslClient::socketEncrypted()
  {
      form->sessionOutput->clear();
      form->sessionInput->setFocus();

      QPalette palette;
      palette.setColor(QPalette::Base, QColor(255, 255, 192));
      form->hostNameEdit->setPalette(palette);

      const QSslCipher cipher = socket->sessionCipher();
      const QString cipherInfo = QString("%1, %2 (%3/%4)").arg(cipher.authenticationMethod())
                                         .arg(cipher.name()).arg(cipher.usedBits())
                                         .arg(cipher.supportedBits());;
      form->cipherLabel->setText(cipherInfo);
      padLock->show();
  }

  void SslClient::socketReadyRead()
  {
      appendString(QString::fromUtf8(socket->readAll()));
  }

  void SslClient::sendData()
  {
      const QString input = form->sessionInput->text();
      appendString(input + '\n');
      socket->write(input.toUtf8() + "\r\n");
      form->sessionInput->clear();
  }

  void SslClient::socketError(QAbstractSocket::SocketError)
  {
      if (handlingSocketError)
          return;

      handlingSocketError = true;
      QMessageBox::critical(this, tr("Connection error"), socket->errorString());
      handlingSocketError = false;
  }

  void SslClient::sslErrors(const QList<QSslError> &errors)
  {
      QDialog errorDialog(this);
      Ui_SslErrors ui;
      ui.setupUi(&errorDialog);
      connect(ui.certificateChainButton, &QPushButton::clicked,
              this, &SslClient::displayCertificateInfo);

      for (const auto &error : errors)
          ui.sslErrorList->addItem(error.errorString());

      executingDialog = true;
      if (errorDialog.exec() == QDialog::Accepted)
          socket->ignoreSslErrors();
      executingDialog = false;

      // did the socket state change?
      if (socket->state() != QAbstractSocket::ConnectedState)
          socketStateChanged(socket->state());
  }

  void SslClient::displayCertificateInfo()
  {
      CertificateInfo info;
      info.setCertificateChain(socket->peerCertificateChain());
      info.exec();
  }

  void SslClient::setupUi()
  {
      if (form)
          return;

      form = new Ui_Form;
      form->setupUi(this);
      form->hostNameEdit->setSelection(0, form->hostNameEdit->text().size());
      form->sessionOutput->setHtml(tr("&lt;not connected&gt;"));

      connect(form->hostNameEdit, SIGNAL(textChanged(QString)),
              this, SLOT(updateEnabledState()));
      connect(form->connectButton, SIGNAL(clicked()),
              this, SLOT(secureConnect()));
      connect(form->sendButton, SIGNAL(clicked()),
              this, SLOT(sendData()));

      padLock = new QToolButton;
      padLock->setIcon(QIcon(":/encrypted.png"));
      connect(padLock, SIGNAL(clicked()), this, SLOT(displayCertificateInfo()));

  #if QT_CONFIG(cursor)
      padLock->setCursor(Qt::ArrowCursor);
  #endif
      padLock->setToolTip(tr("Display encryption details."));

      const int extent = form->hostNameEdit->height() - 2;
      padLock->resize(extent, extent);
      padLock->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Ignored);

      QHBoxLayout *layout = new QHBoxLayout(form->hostNameEdit);
      layout->setMargin(form->hostNameEdit->style()->pixelMetric(QStyle::PM_DefaultFrameWidth));
      layout->setSpacing(0);
      layout->addStretch();
      layout->addWidget(padLock);

      form->hostNameEdit->setLayout(layout);
      padLock->hide();
  }

  void SslClient::setupSecureSocket()
  {
      if (socket)
          return;

      socket = new QSslSocket(this);

      connect(socket, SIGNAL(stateChanged(QAbstractSocket::SocketState)),
              this, SLOT(socketStateChanged(QAbstractSocket::SocketState)));
      connect(socket, SIGNAL(encrypted()),
              this, SLOT(socketEncrypted()));
      connect(socket, SIGNAL(error(QAbstractSocket::SocketError)),
              this, SLOT(socketError(QAbstractSocket::SocketError)));
      connect(socket, SIGNAL(sslErrors(QList<QSslError>)),
              this, SLOT(sslErrors(QList<QSslError>)));
      connect(socket, SIGNAL(readyRead()),
              this, SLOT(socketReadyRead()));

  }

  void SslClient::appendString(const QString &line)
  {
      QTextCursor cursor(form->sessionOutput->textCursor());
      cursor.movePosition(QTextCursor::End);
      cursor.insertText(line);
      form->sessionOutput->verticalScrollBar()->setValue(form->sessionOutput->verticalScrollBar()->maximum());
  }