I wrote that code:
Server:
Qt Code: 
  1. //H
  2.  
  3. #ifndef POLACZENIESSL_H
  4. #define POLACZENIESSL_H
  5. #include <QTcpServer>
  6. #include <QTcpSocket>
  7. #include <QSslSocket>
  8. #include <QFile>
  9. #include <QSslKey>
  10. #include <QAbstractSocket>
  11. class PolaczenieSSL : public QTcpServer
  12. {
  13.     Q_OBJECT
  14. public:
  15.     PolaczenieSSL(QWidget *parent = 0);
  16.     ~PolaczenieSSL();
  17. private:
  18.     void incomingConnection(int port);
  19. private slots:
  20.     void gotowy();
  21. };
  22.  
  23. #endif // POLACZENIESSL_H
  24.  
  25. //CPP
  26.  
  27. #include "polaczeniessl.h"
  28.  
  29. PolaczenieSSL::PolaczenieSSL(QWidget *parent)
  30. {
  31.  
  32. }
  33. PolaczenieSSL::~PolaczenieSSL()
  34. {
  35.  
  36. }
  37. void PolaczenieSSL::incomingConnection(int port)
  38. {
  39.     qDebug()<<"incomingConnection";
  40.     QSslSocket *serverSocket = new QSslSocket;
  41.     serverSocket->setProtocol(QSsl::AnyProtocol);
  42.     serverSocket->ignoreSslErrors();
  43.     QFile *file = new QFile("server.key");
  44.     QSslKey key(file, QSsl::Rsa, QSsl::Pem, QSsl::PrivateKey, "server");
  45.     serverSocket->setPrivateKey(key);
  46.     serverSocket->setLocalCertificate("server.csr");
  47.     serverSocket->addCaCertificates("/etc/ssl/certs");
  48.     if (serverSocket->setSocketDescriptor(port))
  49.     {
  50.         connect(serverSocket, SIGNAL(encrypted()), this, SLOT(gotowy()));
  51.         serverSocket->startServerEncryption();
  52.         qDebug()<<serverSocket->errorString();
  53.  
  54.     }
  55.     else
  56.     {
  57.         delete serverSocket;
  58.     }
  59. }
  60.  
  61. void PolaczenieSSL::gotowy()
  62. {
  63.     qDebug()<<"gotowy";
  64. }
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On console, when client started connection:
Qt Code: 
  1. incomingConnection 
  2. "Unknown error"
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What is it wrong?