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Diffstat (limited to 'src/network/ssl/qsslserver.cpp')
| -rw-r--r-- | src/network/ssl/qsslserver.cpp | 412 |
1 files changed, 412 insertions, 0 deletions
diff --git a/src/network/ssl/qsslserver.cpp b/src/network/ssl/qsslserver.cpp new file mode 100644 index 0000000000..40a6a6f526 --- /dev/null +++ b/src/network/ssl/qsslserver.cpp @@ -0,0 +1,412 @@ +// Copyright (C) 2022 The Qt Company Ltd. +// Copyright (C) 2016 Kurt Pattyn <pattyn.kurt@gmail.com>. +// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only + +/*! + \class QSslServer + + \ingroup network + \ingroup ssl + \inmodule QtNetwork + \since 6.4 + + \brief Implements an encrypted, secure TCP server over TLS. + + Class to use in place of QTcpServer to implement TCP server using + Transport Layer Security (TLS). + + To configure the secure handshake settings, use the applicable setter + functions on a QSslConfiguration object, and then use it as an argument + to the setSslConfiguration() function. All following incoming + connections handled will use these settings. + + To start listening to incoming connections use the listen() function + inherited from QTcpServer. Other settings can be configured by using the + setter functions inherited from the QTcpServer class. + + Connect to the signals of this class to respond to the incoming connection + attempts. They are the same as the signals on QSslSocket, but also + passes a pointer to the socket in question. + + When responding to the pendingConnectionAvailable() signal, use the + nextPendingConnection() function to fetch the next incoming connection and + take it out of the pending connection queue. The QSslSocket is a child of + the QSslServer and will be deleted when the QSslServer is deleted. It is + still a good idea to destroy the object explicitly when you are done + with it, to avoid wasting memory. + + \sa QTcpServer, QSslConfiguration, QSslSocket +*/ + +/*! + \fn void QSslServer::peerVerifyError(QSslSocket *socket, const QSslError &error) + + QSslServer can emit this signal several times during the SSL handshake, + before encryption has been established, to indicate that an error has + occurred while establishing the identity of the peer. The \a error is + usually an indication that \a socket is unable to securely identify the + peer. + + This signal provides you with an early indication when something's wrong. + By connecting to this signal, you can manually choose to tear down the + connection from inside the connected slot before the handshake has + completed. If no action is taken, QSslServer will proceed to emitting + sslErrors(). + + \sa sslErrors() +*/ + +/*! + \fn void QSslServer::sslErrors(QSslSocket *socket, const QList<QSslError> &errors); + + QSslServer emits this signal after the SSL handshake to indicate that one + or more errors have occurred while establishing the identity of the + peer. The errors are usually an indication that \a socket is unable to + securely identify the peer. Unless any action is taken, the connection + will be dropped after this signal has been emitted. + + If you want to continue connecting despite the errors that have occurred, + you must call QSslSocket::ignoreSslErrors() from inside a slot connected to + this signal. If you need to access the error list at a later point, you + can call sslHandshakeErrors(). + + \a errors contains one or more errors that prevent QSslSocket from + verifying the identity of the peer. + + \note You cannot use Qt::QueuedConnection when connecting to this signal, + or calling QSslSocket::ignoreSslErrors() will have no effect. + + \sa peerVerifyError() +*/ + +/*! + \fn void QSslServer::errorOccurred(QSslSocket *socket, QAbstractSocket::SocketError socketError) + + This signal is emitted after an error occurred during handshake. The + \a socketError parameter describes the type of error that occurred. + + The \a socket is automatically deleted after this signal is emitted if the + socket handshake has not reached encrypted state. But if the \a socket is + successfully encrypted, it is inserted into the QSslServer's pending + connections queue. When the user has called + QTcpServer::nextPendingConnection() it is the user's responsibility to + destroy the \a socket or the \a socket will not be destroyed until the + QSslServer object is destroyed. If an error occurs on a \a socket after + it has been inserted into the pending connections queue, this signal + will not be emitted, and the \a socket will not be removed or destroyed. + + \note You cannot use Qt::QueuedConnection when connecting to this signal, + or the \a socket will have been already destroyed when the signal is + handled. + + \sa QSslSocket::error(), errorString() +*/ + +/*! + \fn void QSslServer::preSharedKeyAuthenticationRequired(QSslSocket *socket, + QSslPreSharedKeyAuthenticator *authenticator) + + QSslServer emits this signal when \a socket negotiates a PSK ciphersuite, + and therefore PSK authentication is then required. + + When using PSK, the server must supply a valid identity and a valid pre + shared key, in order for the SSL handshake to continue. + Applications can provide this information in a slot connected to this + signal, by filling in the passed \a authenticator object according to their + needs. + + \note Ignoring this signal, or failing to provide the required credentials, + will cause the handshake to fail, and therefore the connection to be aborted. + + \note The \a authenticator object is owned by the \a socket and must not be + deleted by the application. + + \sa QSslPreSharedKeyAuthenticator +*/ + +/*! + \fn void QSslServer::alertSent(QSslSocket *socket, QSsl::AlertLevel level, QSsl::AlertType type, + const QString &description) + + QSslServer emits this signal if an alert message was sent from \a socket + to a peer. \a level describes if it was a warning or a fatal error. + \a type gives the code of the alert message. When a textual description + of the alert message is available, it is supplied in \a description. + + \note This signal is mostly informational and can be used for debugging + purposes, normally it does not require any actions from the application. + \note Not all backends support this functionality. + + \sa alertReceived(), QSsl::AlertLevel, QSsl::AlertType +*/ + +/*! + \fn void QSslServer::alertReceived(QSslSocket *socket, QSsl::AlertLevel level, QSsl::AlertType + type, const QString &description) + + QSslServer emits this signal if an alert message was received by the + \a socket from a peer. \a level tells if the alert was fatal or it was a + warning. \a type is the code explaining why the alert was sent. + When a textual description of the alert message is available, it is + supplied in \a description. + + \note The signal is mostly for informational and debugging purposes and does not + require any handling in the application. If the alert was fatal, underlying + backend will handle it and close the connection. + \note Not all backends support this functionality. + + \sa alertSent(), QSsl::AlertLevel, QSsl::AlertType +*/ + +/*! + \fn void QSslServer::handshakeInterruptedOnError(QSslSocket *socket, const QSslError &error) + + QSslServer emits this signal if a certificate verification error was found + by \a socket and if early error reporting was enabled in QSslConfiguration. + An application is expected to inspect the \a error and decide if it wants + to continue the handshake, or abort it and send an alert message to the + peer. The signal-slot connection must be direct. + + \sa QSslSocket::continueInterruptedHandshake(), sslErrors(), + QSslConfiguration::setHandshakeMustInterruptOnError() +*/ + +/*! + \fn void QSslServer::startedEncryptionHandshake(QSslSocket *socket) + + This signal is emitted when the client, connected to \a socket, + initiates the TLS handshake. +*/ + +#include "qsslserver.h" +#include "qsslserver_p.h" + +#include <QtNetwork/QSslSocket> +#include <QtNetwork/QSslCipher> + +QT_BEGIN_NAMESPACE + +/*! + \internal +*/ +QSslServerPrivate::QSslServerPrivate() : + sslConfiguration(QSslConfiguration::defaultConfiguration()) +{ +} + +/*! + Constructs a new QSslServer with the given \a parent. +*/ +QSslServer::QSslServer(QObject *parent) : + QTcpServer(QAbstractSocket::TcpSocket, *new QSslServerPrivate, parent) +{ +} + +/*! + Destroys the QSslServer. + + All open connections are closed. +*/ +QSslServer::~QSslServer() +{ +} + +/*! + Sets the \a sslConfiguration to use for all following incoming connections. + + This must be called before listen() to ensure that the desired + configuration was in use during all handshakes. + + \sa QSslSocket::setSslConfiguration() +*/ +void QSslServer::setSslConfiguration(const QSslConfiguration &sslConfiguration) +{ + Q_D(QSslServer); + d->sslConfiguration = sslConfiguration; +} + +/*! + Returns the current ssl configuration. +*/ +QSslConfiguration QSslServer::sslConfiguration() const +{ + const Q_D(QSslServer); + return d->sslConfiguration; +} + +/*! + Sets the \a timeout to use for all incoming handshakes, in milliseconds. + + This is relevant in the scenario where a client, whether malicious or + accidental, connects to the server but makes no attempt at communicating or + initiating a handshake. QSslServer will then automatically end the + connection after \a timeout milliseconds have elapsed. + + By default the timeout is 5000 milliseconds (5 seconds). + + \note The underlying TLS framework may have their own timeout logic now or + in the future, this function does not affect that. + + \note The \a timeout passed to this function will only apply to \e{new} + connections. If a client is already connected it will use the timeout which + was set when it connected. + + \sa handshakeTimeout() +*/ +void QSslServer::setHandshakeTimeout(int timeout) +{ + Q_D(QSslServer); + d->handshakeTimeout = timeout; +} + +/*! + Returns the currently configured handshake timeout. + + \sa setHandshakeTimeout() +*/ +int QSslServer::handshakeTimeout() const +{ + const Q_D(QSslServer); + return d->handshakeTimeout; +} + +/*! + Called when a new connection is established. + + Converts \a socket to a QSslSocket. + + \reimp +*/ +void QSslServer::incomingConnection(qintptr socket) +{ + QSslSocket *pSslSocket = new QSslSocket(this); + + pSslSocket->setSslConfiguration(sslConfiguration()); + + if (Q_LIKELY(pSslSocket->setSocketDescriptor(socket))) { + connect(pSslSocket, &QSslSocket::peerVerifyError, this, + [this, pSslSocket](const QSslError &error) { + Q_EMIT peerVerifyError(pSslSocket, error); + }); + connect(pSslSocket, &QSslSocket::sslErrors, this, + [this, pSslSocket](const QList<QSslError> &errors) { + Q_EMIT sslErrors(pSslSocket, errors); + }); + connect(pSslSocket, &QAbstractSocket::errorOccurred, this, + [this, pSslSocket](QAbstractSocket::SocketError error) { + Q_EMIT errorOccurred(pSslSocket, error); + if (!pSslSocket->isEncrypted()) + pSslSocket->deleteLater(); + }); + connect(pSslSocket, &QSslSocket::encrypted, this, [this, pSslSocket]() { + Q_D(QSslServer); + d->removeSocketData(quintptr(pSslSocket)); + pSslSocket->disconnect(this); + addPendingConnection(pSslSocket); + }); + connect(pSslSocket, &QSslSocket::preSharedKeyAuthenticationRequired, this, + [this, pSslSocket](QSslPreSharedKeyAuthenticator *authenticator) { + Q_EMIT preSharedKeyAuthenticationRequired(pSslSocket, authenticator); + }); + connect(pSslSocket, &QSslSocket::alertSent, this, + [this, pSslSocket](QSsl::AlertLevel level, QSsl::AlertType type, + const QString &description) { + Q_EMIT alertSent(pSslSocket, level, type, description); + }); + connect(pSslSocket, &QSslSocket::alertReceived, this, + [this, pSslSocket](QSsl::AlertLevel level, QSsl::AlertType type, + const QString &description) { + Q_EMIT alertReceived(pSslSocket, level, type, description); + }); + connect(pSslSocket, &QSslSocket::handshakeInterruptedOnError, this, + [this, pSslSocket](const QSslError &error) { + Q_EMIT handshakeInterruptedOnError(pSslSocket, error); + }); + + d_func()->initializeHandshakeProcess(pSslSocket); + } +} + +void QSslServerPrivate::initializeHandshakeProcess(QSslSocket *socket) +{ + Q_Q(QSslServer); + QMetaObject::Connection readyRead = QObject::connect( + socket, &QSslSocket::readyRead, q, [this]() { checkClientHelloAndContinue(); }); + + QMetaObject::Connection destroyed = + QObject::connect(socket, &QSslSocket::destroyed, q, [this](QObject *obj) { + // This cast is not safe to use since the socket is inside the + // QObject dtor, but we only use the pointer value! + removeSocketData(quintptr(obj)); + }); + auto it = socketData.emplace(quintptr(socket), readyRead, destroyed, std::make_shared<QTimer>()); + it->timeoutTimer->setSingleShot(true); + it->timeoutTimer->callOnTimeout(q, [this, socket]() { handleHandshakeTimedOut(socket); }); + it->timeoutTimer->setInterval(handshakeTimeout); + it->timeoutTimer->start(); +} + +// This function may be called while in the socket's QObject dtor, __never__ use +// the socket for anything other than a lookup! +void QSslServerPrivate::removeSocketData(quintptr socket) +{ + auto it = socketData.find(socket); + if (it != socketData.end()) { + it->disconnectSignals(); + socketData.erase(it); + } +} + +int QSslServerPrivate::totalPendingConnections() const +{ + // max pending connections is int, so this cannot exceed that + return QTcpServerPrivate::totalPendingConnections() + int(socketData.size()); +} + +void QSslServerPrivate::checkClientHelloAndContinue() +{ + Q_Q(QSslServer); + QSslSocket *socket = qobject_cast<QSslSocket *>(q->sender()); + if (Q_UNLIKELY(!socket) || socket->bytesAvailable() <= 0) + return; + + char byte = '\0'; + if (socket->peek(&byte, 1) != 1) { + socket->deleteLater(); + return; + } + + auto it = socketData.find(quintptr(socket)); + const bool foundData = it != socketData.end(); + if (foundData && it->readyReadConnection) + QObject::disconnect(std::exchange(it->readyReadConnection, {})); + + constexpr char CLIENT_HELLO = 0x16; + if (byte != CLIENT_HELLO) { + socket->disconnectFromHost(); + socket->deleteLater(); + return; + } + + // Be nice and restart the timeout timer since some progress was made + if (foundData) + it->timeoutTimer->start(); + + socket->startServerEncryption(); + Q_EMIT q->startedEncryptionHandshake(socket); +} + +void QSslServerPrivate::handleHandshakeTimedOut(QSslSocket *socket) +{ + Q_Q(QSslServer); + removeSocketData(quintptr(socket)); + socket->disconnectFromHost(); + Q_EMIT q->errorOccurred(socket, QAbstractSocket::SocketTimeoutError); + socket->deleteLater(); + if (!socketEngine->isReadNotificationEnabled() && totalPendingConnections() < maxConnections) + q->resumeAccepting(); +} + +QT_END_NAMESPACE + +#include "moc_qsslserver.cpp" |