QSslPreSharedKeyAuthenticator Class

  • Header: QSslPreSharedKeyAuthenticator

  • Since: Qt 5.5

  • qmake: QT += network

  • Group: QSslPreSharedKeyAuthenticator is part of Network Programming API, ssl, shared

Detailed Description

The QSslPreSharedKeyAuthenticator class is used by an SSL socket to provide the required authentication data in a pre shared key (PSK) ciphersuite.

In a PSK handshake, the client must derive a key, which must match the key set on the server. The exact algorithm of deriving the key depends on the application; however, for this purpose, the server may send an identity hint to the client. This hint, combined with other information (for instance a passphrase), is then used by the client to construct the shared key.

The QSslPreSharedKeyAuthenticator provides means to client applications for completing the PSK handshake. The client application needs to connect a slot to the QSslSocket::preSharedKeyAuthenticationRequired() signal:

 
Sélectionnez
    connect(socket, &QSslSocket::preSharedKeyAuthenticationRequired,
            this, &AuthManager::handlePreSharedKeyAuthentication);

The signal carries a QSslPreSharedKeyAuthenticator object containing the identity hint the server sent to the client, and which must be filled with the corresponding client identity and the derived key:

 
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    void AuthManager::handlePreSharedKeyAuthentication(QSslPreSharedKeyAuthenticator *authenticator)
    {
        authenticator->setIdentity("My Qt App");

        const QByteArray key = deriveKey(authenticator->identityHint(), passphrase);
        authenticator->setPreSharedKey(key);
    }

PSK ciphersuites are supported only when using OpenSSL 1.0.1 (or greater) as the SSL backend.

PSK is currently only supported in OpenSSL.

See Also

See also QSslSocket

Member Function Documentation

 

QSslPreSharedKeyAuthenticator::~QSslPreSharedKeyAuthenticator()

Destroys the QSslPreSharedKeyAuthenticator object.

Q_DECL_IMPORT QSslPreSharedKeyAuthenticator::maximumIdentityLength() const

Returns the maximum length, in bytes, of the PSK client identity.

it is possible to set an identity whose length is greater than maximumIdentityLength(); in this case, only the first maximumIdentityLength() bytes will be actually sent to the server.

See Also

See also setIdentity()

Q_DECL_IMPORT QSslPreSharedKeyAuthenticator::maximumPreSharedKeyLength() const

Returns the maximum length, in bytes, of the pre shared key.

it is possible to set a key whose length is greater than the maximumPreSharedKeyLength(); in this case, only the first maximumPreSharedKeyLength() bytes will be actually sent to the server.

See Also

See also setPreSharedKey()

Q_DECL_IMPORT QSslPreSharedKeyAuthenticator::setIdentity(const class QByteArray &identity)

Sets the PSK client identity (to be advised to the server) to identity.

it is possible to set an identity whose length is greater than maximumIdentityLength(); in this case, only the first maximumIdentityLength() bytes will be actually sent to the server.

See Also