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 <QtWidgets/QScrollBar>
  #include <QtWidgets/QStyle>
  #include <QtWidgets/QToolButton>
  #include <QtWidgets/QMessageBox>
  #include <QtNetwork/QSslCipher>

  SslClient::SslClient(QWidget *parent)
      : QWidget(parent), socket(0), padLock(0), executingDialog(false)
  {
      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()));
  }

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

  void SslClient::updateEnabledState()
  {
      bool unconnected = !socket || 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());

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

  void SslClient::secureConnect()
  {
      if (!socket) {
          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()));
      }

      socket->connectToHostEncrypted(form->hostNameEdit->text(), form->portBox->value());
      updateEnabledState();
  }

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

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

  void SslClient::socketEncrypted()
  {
      if (!socket)
          return;                 // might have disconnected already

      form->sessionOutput->clear();
      form->sessionInput->setFocus();

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

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

      if (!padLock) {
          padLock = new QToolButton;
          padLock->setIcon(QIcon(":/encrypted.png"));
  #ifndef QT_NO_CURSOR
          padLock->setCursor(Qt::ArrowCursor);
  #endif
          padLock->setToolTip(tr("Display encryption details."));

          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);

          connect(padLock, SIGNAL(clicked()),
                  this, SLOT(displayCertificateInfo()));
      } else {
          padLock->show();
      }
  }

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

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

  void SslClient::socketError(QAbstractSocket::SocketError)
  {
      QMessageBox::critical(this, tr("Connection error"), socket->errorString());
  }

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

      foreach (const QSslError &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 = new CertificateInfo(this);
      info->setCertificateChain(socket->peerCertificateChain());
      info->exec();
      info->deleteLater();
  }

  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());
  }