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Qt SSL Unable to init SSL Context error



  • I am trying to connect an SSL client to an SSL server using the Qt SSL classes, but I am getting the error "Unable to init SSL Context". I made my code as easy as possible to figure out what the problem could be. I created the private key and certificate with the following command on my MacOS terminal:
    openssl req -x509 -newkey rsa:4096 -keyout privatekey.pem -out certificate.pem -days 365. So it looks like openssl is installed? QSslSocket::supportSsl() also returns true. What do I need to do to make the server and client work so that they can communicate with eachother? My code and output is below. Thank you in advance!

    Client:

    #include <QSslSocket>
    #include <QFile>
    
    int main() {
        QSslSocket* socket = new QSslSocket;
        qDebug() << socket->supportsSsl();
    
        socket->setProtocol(QSsl::TlsV1_2);
        socket->connectToHostEncrypted("192.168.2.33", 5555, "192.168.2.33");
        if (!socket->waitForEncrypted()) {
            qDebug() << socket->errorString();
            return 0;
        }
        qDebug() << "Encryption succesfull";
        socket->write("Client here");
        qDebug() << "Written to socket";
        while (socket->waitForReadyRead()) {
            qDebug() << "Reading";
            qDebug() << socket->readAll().data();
        }
    
        qDebug() << "Ending program";
        delete socket;
        return 0;
    }
    

    Server:

    #include <QTcpServer>
    #include <QSslSocket>
    
    int main() {
        QTcpServer* server = new QTcpServer;
        QSslSocket* socket = new QSslSocket;
        qDebug() << socket->supportsSsl();
    
        socket->setLocalCertificate("/mylocalfolders/certificate.pem");
        socket->setPrivateKey("/mylocalfolders/privatekey.pem",QSsl::Rsa,QSsl::Pem,"secret");
        socket->setProtocol(QSsl::TlsV1_2);
        server->listen(QHostAddress("192.168.2.33"), 5555);
    
        if(server->waitForNewConnection(-1)) {
            qDebug() << "New connection";
            socket->startServerEncryption();
            if (!socket->waitForEncrypted()) {
                qDebug() << socket->errorString();
                return 0;
            }
            qDebug() << "Encryption succesfull";
            socket->write("Server here");
            qDebug() << "Written to socket";
            while (socket->waitForReadyRead()) {
                qDebug() << "Reading";
                qDebug() << socket->readAll().data();
            }
        }
    
        qDebug() << "Ending program";
        delete server;
        delete socket;
        return 0;
    }
    

    Output client:

    true
    "The remote host closed the connection"
    

    Output server:

    true
    New connection
    "Unable to init SSL Context"
    

  • Lifetime Qt Champion

    Hi and welcome to devnet,

    What version of Qt are you using ?
    On what version of macOS ?



  • Thank you!
    I am using Qt Creator 4.6.1 based on Qt 5.10.1 on macOS High Sierra 10.13.4.


  • Lifetime Qt Champion

    I wonder if it's related to QTBUG-59068.

    Otherwise, you maybe using a key with the "modern" header which I remember has caused some trouble to another member. Can you show the header of your key ?



  • The header of my privatekey.pem is BEGIN ENCRYPTED PRIVATE KEY.

    Today I tried to run the code again. Strangely the output is different!!! I am absolutely sure I didn't change something! The output of my server program is now:

    true
    Ending program
    

    And my client:

    true
    "Unknown error"
    

    The "Unknown error" appears exactly 30 seconds after I start the client. True and the server output showed up immediately.


  • Lifetime Qt Champion

    Update of Qt version ?
    Update of OpenSSL ?


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