QSslSocket¶

PyQt5.QtNetwork.QSslSocket: Inherits from QTcpSocket.

Description¶

The QSslSocket class provides an SSL encrypted socket for both clients and servers.

QSslSocket establishes a secure, encrypted TCP connection you can use for transmitting encrypted data. It can operate in both client and server mode, and it supports modern SSL protocols, including SSL 3 and TLS 1.2. By default, QSslSocket uses only SSL protocols which are considered to be secure (SecureProtocols), but you can change the SSL protocol by calling setProtocol() as long as you do it before the handshake has started.

SSL encryption operates on top of the existing TCP stream after the socket enters the ConnectedState. There are two simple ways to establish a secure connection using QSslSocket: With an immediate SSL handshake, or with a delayed SSL handshake occurring after the connection has been established in unencrypted mode.

The most common way to use QSslSocket is to construct an object and start a secure connection by calling connectToHostEncrypted(). This method starts an immediate SSL handshake once the connection has been established.

# QSslSocket *socket = new QSslSocket(this);
# connect(socket, SIGNAL(encrypted()), this, SLOT(ready()));

# socket->connectToHostEncrypted("imap.example.com", 993);

As with a plain QTcpSocket, QSslSocket enters the HostLookupState, ConnectingState, and finally the ConnectedState, if the connection is successful. The handshake then starts automatically, and if it succeeds, the encrypted signal is emitted to indicate the socket has entered the encrypted state and is ready for use.

Note that data can be written to the socket immediately after the return from connectToHostEncrypted() (i.e., before the encrypted signal is emitted). The data is queued in QSslSocket until after the encrypted signal is emitted.

An example of using the delayed SSL handshake to secure an existing connection is the case where an SSL server secures an incoming connection. Suppose you create an SSL server class as a subclass of QTcpServer. You would override incomingConnection() with something like the example below, which first constructs an instance of QSslSocket and then calls setSocketDescriptor() to set the new socket’s descriptor to the existing one passed in. It then initiates the SSL handshake by calling startServerEncryption().

# void SslServer::incomingConnection(qintptr socketDescriptor)
# {
#     QSslSocket *serverSocket = new QSslSocket;
#     if (serverSocket->setSocketDescriptor(socketDescriptor)) {
#         addPendingConnection(serverSocket);
#         connect(serverSocket, &QSslSocket::encrypted, this, &SslServer::ready);
#         serverSocket->startServerEncryption();
#     } else {
#         delete serverSocket;
#     }
# }

If an error occurs, QSslSocket emits the sslErrors signal. In this case, if no action is taken to ignore the error(s), the connection is dropped. To continue, despite the occurrence of an error, you can call ignoreSslErrors(), either from within this slot after the error occurs, or any time after construction of the QSslSocket and before the connection is attempted. This will allow QSslSocket to ignore the errors it encounters when establishing the identity of the peer. Ignoring errors during an SSL handshake should be used with caution, since a fundamental characteristic of secure connections is that they should be established with a successful handshake.

Once encrypted, you use QSslSocket as a regular QTcpSocket. When readyRead() is emitted, you can call read(), canReadLine() and readLine(), or getChar() to read decrypted data from QSslSocket’s internal buffer, and you can call write() or putChar() to write data back to the peer. QSslSocket will automatically encrypt the written data for you, and emit encryptedBytesWritten once the data has been written to the peer.

As a convenience, QSslSocket supports QTcpSocket’s blocking functions waitForConnected(), waitForReadyRead(), waitForBytesWritten(), and waitForDisconnected(). It also provides waitForEncrypted(), which will block the calling thread until an encrypted connection has been established.

# QSslSocket socket;
# socket.connectToHostEncrypted("http.example.com", 443);
# if (!socket.waitForEncrypted()) {
#     qDebug() << socket.errorString();
#     return false;
# }

# socket.write("GET / HTTP/1.0\r\n\r\n");
# while (socket.waitForReadyRead())
#     qDebug() << socket.readAll().data();

QSslSocket provides an extensive, easy-to-use API for handling cryptographic ciphers, private keys, and local, peer, and Certification Authority (CA) certificates. It also provides an API for handling errors that occur during the handshake phase.

The following features can also be customized:

The socket’s cryptographic cipher suite can be customized before the handshake phase with setCiphers() and setDefaultCiphers().
The socket’s local certificate and private key can be customized before the handshake phase with setLocalCertificate() and setPrivateKey().
The CA certificate database can be extended and customized with addCaCertificate(), addCaCertificates(), addDefaultCaCertificate(), addDefaultCaCertificates(), and defaultConfiguration().setCaCertificates().

Note: If available, root certificates on Unix (excluding macOS) will be loaded on demand from the standard certificate directories. If you do not want to load root certificates on demand, you need to call either defaultConfiguration().setCaCertificates() before the first SSL handshake is made in your application (for example, via passing systemCaCertificates() to it), or call defaultConfiguration()::setCaCertificates() on your QSslSocket instance prior to the SSL handshake.

For more information about ciphers and certificates, refer to QSslCipher and QSslCertificate.

This product includes software developed by the OpenSSL Project for use in the OpenSSL Toolkit (http://www.openssl.org/).

Note: Be aware of the difference between the bytesWritten() signal and the encryptedBytesWritten signal. For a QTcpSocket, bytesWritten() will get emitted as soon as data has been written to the TCP socket. For a QSslSocket, bytesWritten() will get emitted when the data is being encrypted and encryptedBytesWritten will get emitted as soon as data has been written to the TCP socket.

See also

QSslCertificate, QSslCipher, QSslError.

Enums¶

PeerVerifyMode

Describes the peer verification modes for QSslSocket. The default mode is , which selects an appropriate mode depending on the socket’s QSocket::SslMode.

See also

peerVerifyMode().

Member	Value	Description
AutoVerifyPeer	3	QSslSocket will automatically use for server sockets and for client sockets.
QueryPeer	1	QSslSocket will request a certificate from the peer, but does not require this certificate to be valid. This is useful when you want to display peer certificate details to the user without affecting the actual SSL handshake. This mode is the default for servers.
VerifyNone	0	QSslSocket will not request a certificate from the peer. You can set this mode if you are not interested in the identity of the other side of the connection. The connection will still be encrypted, and your socket will still send its local certificate to the peer if it’s requested.
VerifyPeer	2	QSslSocket will request a certificate from the peer during the SSL handshake phase, and requires that this certificate is valid. On failure, QSslSocket will emit the sslErrors signal. This mode is the default for clients.

SslMode

Describes the connection modes available for QSslSocket.

Member	Value	Description
SslClientMode	1	The socket is a client-side SSL socket. It is either alreayd encrypted, or it is in the SSL handshake phase (see isEncrypted()).
SslServerMode	2	The socket is a server-side SSL socket. It is either already encrypted, or it is in the SSL handshake phase (see isEncrypted()).
UnencryptedMode	0	The socket is unencrypted. Its behavior is identical to QTcpSocket.

Methods¶

__init__(parent: QObject = None): Constructs a QSslSocket object. parent is passed to QObject’s constructor. The new socket’s QSslCipher suite is set to the one returned by the static method defaultCiphers().

abort(): Aborts the current connection and resets the socket. Unlike disconnectFromHost(), this function immediately closes the socket, clearing any pending data in the write buffer.

See also

disconnectFromHost(), close().

addCaCertificate(QSslCertificate)

Adds the certificate to this socket’s CA certificate database. The CA certificate database is used by the socket during the handshake phase to validate the peer’s certificate.

To add multiple certificates, use addCaCertificates().

See also

caCertificates(), setCaCertificates().

addCaCertificates(Iterable[QSslCertificate])

Adds the certificates to this socket’s CA certificate database. The CA certificate database is used by the socket during the handshake phase to validate the peer’s certificate.

For more precise control, use addCaCertificate().

addCaCertificates(str, format: EncodingFormat = Pem, syntax: PatternSyntax = FixedString) → bool

Searches all files in the path for certificates encoded in the specified format and adds them to this socket’s CA certificate database. path must be a file or a pattern matching one or more files, as specified by syntax. Returns true if one or more certificates are added to the socket’s CA certificate database; otherwise returns false.

The CA certificate database is used by the socket during the handshake phase to validate the peer’s certificate.

For more precise control, use addCaCertificate().

See also

addCaCertificate().

@staticmethod addDefaultCaCertificate(QSslCertificate): Adds certificate to the default CA certificate database. Each SSL socket’s CA certificate database is initialized to the default CA certificate database.

See also

defaultCaCertificates(), addCaCertificates().

@staticmethod addDefaultCaCertificates(Iterable[QSslCertificate]): Adds certificates to the default CA certificate database. Each SSL socket’s CA certificate database is initialized to the default CA certificate database.

See also

defaultCaCertificates(), addCaCertificates().

@staticmethod addDefaultCaCertificates(str, format: EncodingFormat = Pem, syntax: PatternSyntax = FixedString) → bool

Searches all files in the path for certificates with the specified encoding and adds them to the default CA certificate database. path can be an explicit file, or it can contain wildcards in the format specified by syntax. Returns true if any CA certificates are added to the default database.

Each SSL socket’s CA certificate database is initialized to the default CA certificate database.

atEnd() → bool: TODO

bytesAvailable() → int: TODO

bytesToWrite() → int: TODO

caCertificates() → List[QSslCertificate]

Use caCertificates() instead.

Returns this socket’s CA certificate database. The CA certificate database is used by the socket during the handshake phase to validate the peer’s certificate. It can be moodified prior to the handshake with addCaCertificate(), addCaCertificates(), and setCaCertificates().

Note: On Unix, this method may return an empty list if the root certificates are loaded on demand.

canReadLine() → bool: TODO

ciphers() → List[QSslCipher]

Use ciphers() instead.

Returns this socket’s current cryptographic cipher suite. This list is used during the socket’s handshake phase for choosing a session cipher. The returned list of ciphers is ordered by descending preference. (i.e., the first cipher in the list is the most preferred cipher). The session cipher will be the first one in the list that is also supported by the peer.

By default, the handshake phase can choose any of the ciphers supported by this system’s SSL libraries, which may vary from system to system. The list of ciphers supported by this system’s SSL libraries is returned by supportedCiphers(). You can restrict the list of ciphers used for choosing the session cipher for this socket by calling setCiphers() with a subset of the supported ciphers. You can revert to using the entire set by calling setCiphers() with the list returned by supportedCiphers().

You can restrict the list of ciphers used for choosing the session cipher for all sockets by calling setDefaultCiphers() with a subset of the supported ciphers. You can revert to using the entire set by calling setCiphers() with the list returned by supportedCiphers().

close(): TODO

connectToHost(str, int, mode: Union[OpenMode, OpenModeFlag] = ReadWrite, protocol: NetworkLayerProtocol = AnyIPProtocol): TODO

connectToHostEncrypted(str, int, mode: Union[OpenMode, OpenModeFlag] = ReadWrite, protocol: NetworkLayerProtocol = AnyIPProtocol): TODO

connectToHostEncrypted(str, int, str, mode: Union[OpenMode, OpenModeFlag] = ReadWrite, protocol: NetworkLayerProtocol = AnyIPProtocol): TODO

@staticmethod defaultCaCertificates() → List[QSslCertificate]

Use caCertificates() on the default QSslConfiguration instead.

Returns the current default CA certificate database. This database is originally set to your system’s default CA certificate database. If no system default database is found, an empty database will be returned. You can override the default CA certificate database with your own CA certificate database using setDefaultCaCertificates().

Each SSL socket’s CA certificate database is initialized to the default CA certificate database.

Note: On Unix, this method may return an empty list if the root certificates are loaded on demand.

@staticmethod defaultCiphers() → List[QSslCipher]

Use ciphers() on the default QSslConfiguration instead.

Returns the default cryptographic cipher suite for all sockets in this application. This list is used during the socket’s handshake phase when negotiating with the peer to choose a session cipher. The list is ordered by preference (i.e., the first cipher in the list is the most preferred cipher).

By default, the handshake phase can choose any of the ciphers supported by this system’s SSL libraries, which may vary from system to system. The list of ciphers supported by this system’s SSL libraries is returned by supportedCiphers().

disconnectFromHost(): TODO

encryptedBytesAvailable() → int: Returns the number of encrypted bytes that are awaiting decryption. Normally, this function will return 0 because QSslSocket decrypts its incoming data as soon as it can.

encryptedBytesToWrite() → int: Returns the number of encrypted bytes that are waiting to be written to the network.

flush() → bool

This function writes as much as possible from the internal write buffer to the underlying network socket, without blocking. If any data was written, this function returns true; otherwise false is returned.

Call this function if you need QSslSocket to start sending buffered data immediately. The number of bytes successfully written depends on the operating system. In most cases, you do not need to call this function, because QAbstractSocket will start sending data automatically once control goes back to the event loop. In the absence of an event loop, call waitForBytesWritten() instead.

See also

write(), waitForBytesWritten().

ignoreSslErrors()

This slot tells QSslSocket to ignore errors during QSslSocket’s handshake phase and continue connecting. If you want to continue with the connection even if errors occur during the handshake phase, then you must call this slot, either from a slot connected to sslErrors, or before the handshake phase. If you don’t call this slot, either in response to errors or before the handshake, the connection will be dropped after the sslErrors signal has been emitted.

If there are no errors during the SSL handshake phase (i.e., the identity of the peer is established with no problems), QSslSocket will not emit the sslErrors signal, and it is unnecessary to call this function.

Warning: Be sure to always let the user inspect the errors reported by the sslErrors signal, and only call this method upon confirmation from the user that proceeding is ok. If there are unexpected errors, the connection should be aborted. Calling this method without inspecting the actual errors will most likely pose a security risk for your application. Use it with great care!

See also

sslErrors.

ignoreSslErrors(Iterable[QSslError])

This is an overloaded function.

This method tells QSslSocket to ignore only the errors given in errors.

Note: Because most SSL errors are associated with a certificate, for most of them you must set the expected certificate this SSL error is related to. If, for instance, you want to connect to a server that uses a self-signed certificate, consider the following snippet:

# QList<QSslCertificate> cert = QSslCertificate::fromPath(QLatin1String("server-certificate.pem"));
# QSslError error(QSslError::SelfSignedCertificate, cert.at(0));
# QList<QSslError> expectedSslErrors;
# expectedSslErrors.append(error);

# QSslSocket socket;
# socket.ignoreSslErrors(expectedSslErrors);
# socket.connectToHostEncrypted("server.tld", 443);

Multiple calls to this function will replace the list of errors that were passed in previous calls. You can clear the list of errors you want to ignore by calling this function with an empty list.

See also

sslErrors.

isEncrypted() → bool

Returns true if the socket is encrypted; otherwise, false is returned.

An encrypted socket encrypts all data that is written by calling write() or putChar() before the data is written to the network, and decrypts all incoming data as the data is received from the network, before you call read(), readLine() or getChar().

QSslSocket emits encrypted when it enters encrypted mode.

You can call sessionCipher() to find which cryptographic cipher is used to encrypt and decrypt your data.

See also

mode().

localCertificate() → QSslCertificate: Returns the socket’s local QSslCertificate, or an empty certificate if no local certificate has been assigned.

See also

setLocalCertificate(), privateKey().

localCertificateChain() → List[QSslCertificate]: TODO

mode() → SslMode

Returns the current mode for the socket; either UnencryptedMode, where QSslSocket behaves identially to QTcpSocket, or one of SslClientMode or SslServerMode, where the client is either negotiating or in encrypted mode.

When the mode changes, QSslSocket emits modeChanged

See also

SslMode.

ocspResponses() → List[QOcspResponse]: TODO

peerCertificate() → QSslCertificate

Returns the peer’s digital certificate (i.e., the immediate certificate of the host you are connected to), or a null certificate, if the peer has not assigned a certificate.

The peer certificate is checked automatically during the handshake phase, so this function is normally used to fetch the certificate for display or for connection diagnostic purposes. It contains information about the peer, including its host name, the certificate issuer, and the peer’s public key.

Because the peer certificate is set during the handshake phase, it is safe to access the peer certificate from a slot connected to the sslErrors signal or the encrypted signal.

If a null certificate is returned, it can mean the SSL handshake failed, or it can mean the host you are connected to doesn’t have a certificate, or it can mean there is no connection.

If you want to check the peer’s complete chain of certificates, use peerCertificateChain() to get them all at once.

See also

peerCertificateChain().

peerCertificateChain() → List[QSslCertificate]

Returns the peer’s chain of digital certificates, or an empty list of certificates.

Peer certificates are checked automatically during the handshake phase. This function is normally used to fetch certificates for display, or for performing connection diagnostics. Certificates contain information about the peer and the certificate issuers, including host name, issuer names, and issuer public keys.

The peer certificates are set in QSslSocket during the handshake phase, so it is safe to call this function from a slot connected to the sslErrors signal or the encrypted signal.

If an empty list is returned, it can mean the SSL handshake failed, or it can mean the host you are connected to doesn’t have a certificate, or it can mean there is no connection.

If you want to get only the peer’s immediate certificate, use peerCertificate().

See also

peerCertificate().

peerVerifyDepth() → int

Returns the maximum number of certificates in the peer’s certificate chain to be checked during the SSL handshake phase, or 0 (the default) if no maximum depth has been set, indicating that the whole certificate chain should be checked.

The certificates are checked in issuing order, starting with the peer’s own certificate, then its issuer’s certificate, and so on.

See also

setPeerVerifyDepth(), peerVerifyMode().

peerVerifyMode() → PeerVerifyMode

Returns the socket’s verify mode. This mode decides whether QSslSocket should request a certificate from the peer (i.e., the client requests a certificate from the server, or a server requesting a certificate from the client), and whether it should require that this certificate is valid.

The default mode is AutoVerifyPeer, which tells QSslSocket to use VerifyPeer for clients and QueryPeer for servers.

peerVerifyName() → str: Returns the different hostname for the certificate validation, as set by setPeerVerifyName() or by connectToHostEncrypted().

See also

setPeerVerifyName(), connectToHostEncrypted().

privateKey() → QSslKey: Returns this socket’s private key.

See also

setPrivateKey(), localCertificate().

protocol() → SslProtocol: Returns the socket’s SSL protocol. By default, SecureProtocols is used.

See also

setProtocol().

readData(int) → bytes: TODO

resume(): TODO

sessionCipher() → QSslCipher

Returns the socket’s cryptographic QSslCipher, or a null cipher if the connection isn’t encrypted. The socket’s cipher for the session is set during the handshake phase. The cipher is used to encrypt and decrypt data transmitted through the socket.

QSslSocket also provides functions for setting the ordered list of ciphers from which the handshake phase will eventually select the session cipher. This ordered list must be in place before the handshake phase begins.

sessionProtocol() → SslProtocol: TODO

setCaCertificates(Iterable[QSslCertificate])

Use setCaCertificates() instead.

Sets this socket’s CA certificate database to be certificates. The certificate database must be set prior to the SSL handshake. The CA certificate database is used by the socket during the handshake phase to validate the peer’s certificate.

The CA certificate database can be reset to the current default CA certificate database by calling this function with the list of CA certificates returned by defaultCaCertificates().

setCiphers(Iterable[QSslCipher])

USe setCiphers() instead.

Sets the cryptographic cipher suite for this socket to ciphers, which must contain a subset of the ciphers in the list returned by supportedCiphers().

Restricting the cipher suite must be done before the handshake phase, where the session cipher is chosen.

setCiphers(str)

Use setCiphers() instead.

Sets the cryptographic cipher suite for this socket to ciphers, which is a colon-separated list of cipher suite names. The ciphers are listed in order of preference, starting with the most preferred cipher. For example:

# QSslSocket socket;
# socket.setCiphers("DHE-RSA-AES256-SHA:DHE-DSS-AES256-SHA:AES256-SHA");

Each cipher name in ciphers must be the name of a cipher in the list returned by supportedCiphers(). Restricting the cipher suite must be done before the handshake phase, where the session cipher is chosen.

@staticmethod setDefaultCaCertificates(Iterable[QSslCertificate])

Use setCaCertificates() on the default QSslConfiguration instead.

Sets the default CA certificate database to certificates. The default CA certificate database is originally set to your system’s default CA certificate database. You can override the default CA certificate database with your own CA certificate database using this function.

Each SSL socket’s CA certificate database is initialized to the default CA certificate database.

@staticmethod setDefaultCiphers(Iterable[QSslCipher])

Use setCiphers() on the default QSslConfiguration instead.

Sets the default cryptographic cipher suite for all sockets in this application to ciphers, which must contain a subset of the ciphers in the list returned by supportedCiphers().

Restricting the default cipher suite only affects SSL sockets that perform their handshake phase after the default cipher suite has been changed.

setLocalCertificate(QSslCertificate)

Sets the socket’s local certificate to certificate. The local certificate is necessary if you need to confirm your identity to the peer. It is used together with the private key; if you set the local certificate, you must also set the private key.

The local certificate and private key are always necessary for server sockets, but are also rarely used by client sockets if the server requires the client to authenticate.

Note: Secure Transport SSL backend on macOS may update the default keychain (the default is probably your login keychain) by importing your local certificates and keys. This can also result in system dialogs showing up and asking for permission when your application is using these private keys. If such behavior is undesired, set the QT_SSL_USE_TEMPORARY_KEYCHAIN environment variable to a non-zero value; this will prompt QSslSocket to use its own temporary keychain.

See also

localCertificate(), setPrivateKey().

setLocalCertificate(str, format: EncodingFormat = Pem)

This is an overloaded function.

Sets the socket’s local QSslCertificate to the first one found in file path, which is parsed according to the specified format.

setLocalCertificateChain(Iterable[QSslCertificate]): TODO

setPeerVerifyDepth(int)

Sets the maximum number of certificates in the peer’s certificate chain to be checked during the SSL handshake phase, to depth. Setting a depth of 0 means that no maximum depth is set, indicating that the whole certificate chain should be checked.

The certificates are checked in issuing order, starting with the peer’s own certificate, then its issuer’s certificate, and so on.

See also

peerVerifyDepth(), setPeerVerifyMode().

setPeerVerifyMode(PeerVerifyMode)

Sets the socket’s verify mode to mode. This mode decides whether QSslSocket should request a certificate from the peer (i.e., the client requests a certificate from the server, or a server requesting a certificate from the client), and whether it should require that this certificate is valid.

The default mode is AutoVerifyPeer, which tells QSslSocket to use VerifyPeer for clients and QueryPeer for servers.

Setting this mode after encryption has started has no effect on the current connection.

setPeerVerifyName(str): Sets a different host name, given by hostName, for the certificate validation instead of the one used for the TCP connection.

See also

peerVerifyName(), connectToHostEncrypted().

setPrivateKey(QSslKey)

Sets the socket’s private QSslKey to key. The private key and the local QSslCertificate are used by clients and servers that must prove their identity to SSL peers.

Both the key and the local certificate are required if you are creating an SSL server socket. If you are creating an SSL client socket, the key and local certificate are required if your client must identify itself to an SSL server.

See also

privateKey(), setLocalCertificate().

setPrivateKey(str, algorithm: KeyAlgorithm = Rsa, format: EncodingFormat = Pem, passPhrase: Union[QByteArray, bytes, bytearray] = QByteArray())

This is an overloaded function.

Reads the string in file fileName and decodes it using a specified algorithm and encoding format to construct an QSslKey. If the encoded key is encrypted, passPhrase is used to decrypt it.

The socket’s private key is set to the constructed key. The private key and the local QSslCertificate are used by clients and servers that must prove their identity to SSL peers.

Both the key and the local certificate are required if you are creating an SSL server socket. If you are creating an SSL client socket, the key and local certificate are required if your client must identify itself to an SSL server.

See also

privateKey(), setLocalCertificate().

setProtocol(SslProtocol): Sets the socket’s SSL protocol to protocol. This will affect the next initiated handshake; calling this function on an already-encrypted socket will not affect the socket’s protocol.

See also

protocol().

setReadBufferSize(int): Sets the size of QSslSocket’s internal read buffer to be size bytes.

setSocketDescriptor(sip.voidptr, state: SocketState = ConnectedState, mode: Union[OpenMode, OpenModeFlag] = ReadWrite) → bool: TODO

setSocketOption(SocketOption, Any): TODO

setSslConfiguration(QSslConfiguration)

Sets the socket’s SSL configuration to be the contents of configuration. This function sets the local certificate, the ciphers, the private key and the CA certificates to those stored in configuration.

It is not possible to set the SSL-state related fields.

socketOption(SocketOption) → Any: TODO

sslConfiguration() → QSslConfiguration

Returns the socket’s SSL configuration state. The default SSL configuration of a socket is to use the default ciphers, default CA certificates, no local private key or certificate.

The SSL configuration also contains fields that can change with time without notice.

sslErrors() → List[QSslError]: Returns a list of the last SSL errors that occurred. This is the same list as QSslSocket passes via the signal. If the connection has been encrypted with no errors, this function will return an empty list.

See also

connectToHostEncrypted().

@staticmethod sslLibraryBuildVersionNumber() → int: TODO

@staticmethod sslLibraryBuildVersionString() → str: TODO

@staticmethod sslLibraryVersionNumber() → int: TODO

@staticmethod sslLibraryVersionString() → str: TODO

startClientEncryption()

Starts a delayed SSL handshake for a client connection. This function can be called when the socket is in the ConnectedState but still in the UnencryptedMode. If it is not yet connected, or if it is already encrypted, this function has no effect.

Clients that implement STARTTLS functionality often make use of delayed SSL handshakes. Most other clients can avoid calling this function directly by using connectToHostEncrypted() instead, which automatically performs the handshake.

startServerEncryption()

Starts a delayed SSL handshake for a server connection. This function can be called when the socket is in the ConnectedState but still in UnencryptedMode. If it is not connected or it is already encrypted, the function has no effect.

For server sockets, calling this function is the only way to initiate the SSL handshake. Most servers will call this function immediately upon receiving a connection, or as a result of having received a protocol-specific command to enter SSL mode (e.g, the server may respond to receiving the string “STARTTLS\r\n” by calling this function).

The most common way to implement an SSL server is to create a subclass of QTcpServer and reimplement incomingConnection(). The returned socket descriptor is then passed to setSocketDescriptor().

@staticmethod supportedCiphers() → List[QSslCipher]

Use QSslConfiguration::supportedCiphers() instead.

Returns the list of cryptographic ciphers supported by this system. This list is set by the system’s SSL libraries and may vary from system to system.

@staticmethod supportsSsl() → bool: Returns true if this platform supports SSL; otherwise, returns false. If the platform doesn’t support SSL, the socket will fail in the connection phase.

@staticmethod systemCaCertificates() → List[QSslCertificate]

Use QSslConfiguration::systemDefaultCaCertificates instead.

This function provides the CA certificate database provided by the operating system. The CA certificate database returned by this function is used to initialize the database returned by defaultCaCertificates(). You can replace that database with your own with setDefaultCaCertificates().

Note: : On OS X, only certificates that are either trusted for all purposes or trusted for the purpose of SSL in the keychain will be returned.

waitForBytesWritten(msecs: int = 30000) → bool: TODO

waitForConnected(msecs: int = 30000) → bool: Waits until the socket is connected, or msecs milliseconds, whichever happens first. If the connection has been established, this function returns true; otherwise it returns false.

See also

waitForConnected().

waitForDisconnected(msecs: int = 30000) → bool: Waits until the socket has disconnected or msecs milliseconds, whichever comes first. If the connection has been disconnected, this function returns true; otherwise it returns false.

See also

waitForDisconnected().

waitForEncrypted(msecs: int = 30000) → bool

Waits until the socket has completed the SSL handshake and has emitted encrypted, or msecs milliseconds, whichever comes first. If encrypted has been emitted, this function returns true; otherwise (e.g., the socket is disconnected, or the SSL handshake fails), false is returned.

The following example waits up to one second for the socket to be encrypted:

# socket->connectToHostEncrypted("imap", 993);
# if (socket->waitForEncrypted(1000))
#     qDebug("Encrypted!");

If msecs is -1, this function will not time out.

waitForReadyRead(msecs: int = 30000) → bool: TODO

writeData(bytes) → int: TODO

Signals¶

encrypted(): TODO

encryptedBytesWritten(int): TODO

modeChanged(SslMode): TODO

peerVerifyError(QSslError): TODO

preSharedKeyAuthenticationRequired(QSslPreSharedKeyAuthenticator): TODO

sslErrors(): Returns a list of the last SSL errors that occurred. This is the same list as QSslSocket passes via the signal. If the connection has been encrypted with no errors, this function will return an empty list.

See also

connectToHostEncrypted().

sslErrors(Iterable[QSslError]): TODO