QKnxNetIpSessionResponseProxy Class

The QKnxNetIpSessionResponseProxy class provides the means to introspect session response data inside the generic QKnxNetIpFrame class and to create a KNXnet/IP session response frame from provided data. More...

Header: #include <QKnxNetIpSessionResponseProxy>
qmake: QT += knx
Since: Qt 5.12

This class was introduced in Qt 5.12.

Public Types

class Builder
class SecureBuilder

Public Functions

QKnxNetIpSessionResponseProxy(const QKnxNetIpFrame &frame)
bool isValid() const
QKnxByteArray messageAuthenticationCode() const
QKnxByteArray publicKey() const
quint16 secureSessionId() const

Static Public Members

QKnxNetIpSessionResponseProxy::Builder builder()
QKnxNetIpSessionResponseProxy::SecureBuilder secureBuilder()

Detailed Description

This class is part of the Qt KNX module and currently available as a Technology Preview, and therefore the API and functionality provided by the class may be subject to change at any time without prior notice.

This frame will be sent by the KNXnet/IP secure server to the KNXnet/IP secure client control endpoint in response to a received secure session request frame.

Note: When using QKnxNetIpSessionResponseProxy, care must be taken to ensure that the referenced KNXnet/IP frame outlives the proxy on all code paths, lest the proxy ends up referencing deleted data.

The following code sample illustrates how to read the session response information:

auto netIpFrame = QKnxNetIpFrame::fromBytes(...);

const QKnxNetIpSessionResponseProxy proxy(netIpFrame);
if (!proxy.isValid())

auto endPoint = proxy.controlEndpoint();
auto serverPublicKey = proxy.publicKey();
auto authenticationCode = proxy.messageAuthenticationCode();

See also builder(), QKnxNetIpSessionRequestProxy, and Qt KNXnet/IP Connection Classes.

Member Function Documentation

QKnxNetIpSessionResponseProxy::QKnxNetIpSessionResponseProxy(const QKnxNetIpFrame &frame)

Constructs a proxy object to read the session response information carried by the specified KNXnet/IP frame frame.

[static] QKnxNetIpSessionResponseProxy::Builder QKnxNetIpSessionResponseProxy::builder()

Returns a builder object to create a KNXnet/IP session response frame.

bool QKnxNetIpSessionResponseProxy::isValid() const

Returns true if the frame contains initialized values and is in itself valid, otherwise returns false. A valid KNXnet/IP frame consists of at least a valid header and a size in bytes corresponding to the total size of the KNXnet/IP frame header.

Note: KNXnet/IP session response frames currently have a fixed size of 56 bytes.

See also QKnxNetIpFrameHeader::totalSize().

QKnxByteArray QKnxNetIpSessionResponseProxy::messageAuthenticationCode() const

Returns the AES128 CCM message authentication code (MAC) from the generic KNXnet/IP session response frame with a fixed size of 16 bytes.

QKnxByteArray QKnxNetIpSessionResponseProxy::publicKey() const

Returns the public key from the generic KNXnet/IP session response frame. The public key needs to be generated using the Curve25519 algorithm and has a fixed size of 32 bytes.

[static] QKnxNetIpSessionResponseProxy::SecureBuilder QKnxNetIpSessionResponseProxy::secureBuilder()

Returns a builder object to create a KNXnet/IP session response frame.

quint16 QKnxNetIpSessionResponseProxy::secureSessionId() const

Returns the secure session ID from the generic KNXnet/IP session response frame if the object that was passed during construction was valid; otherwise returns a default-constructed value which can be 0.

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