QSsl Namespace

The QSsl namespace declares enums common to all SSL classes in Qt Network. More...

Header: #include <QSsl>
qmake: QT += network
Since: Qt 4.3

This namespace was introduced in Qt 4.3.

Types

enum AlternativeNameEntryType { EmailEntry, DnsEntry, IpAddressEntry }
enum EncodingFormat { Pem, Der }
enum KeyAlgorithm { Rsa, Dsa, Ec, Dh, Opaque }
enum KeyType { PrivateKey, PublicKey }
enum SslOption { SslOptionDisableEmptyFragments, SslOptionDisableSessionTickets, SslOptionDisableCompression, SslOptionDisableServerNameIndication, SslOptionDisableLegacyRenegotiation, …, SslOptionDisableServerCipherPreference }
flags SslOptions
enum SslProtocol { SslV3, SslV2, TlsV1_0, TlsV1_0OrLater, TlsV1, …, SecureProtocols }

Detailed Description

Type Documentation

enum QSsl::AlternativeNameEntryType

Describes the key types for alternative name entries in QSslCertificate.

ConstantValueDescription
QSsl::EmailEntry0An email entry; the entry contains an email address that the certificate is valid for.
QSsl::DnsEntry1A DNS host name entry; the entry contains a host name entry that the certificate is valid for. The entry may contain wildcards.
QSsl::IpAddressEntry2An IP address entry; the entry contains an IP address entry that the certificate is valid for, introduced in Qt 5.13.

Note: In Qt 4, this enum was called AlternateNameEntryType. That name is deprecated in Qt 5.

See also QSslCertificate::subjectAlternativeNames().

enum QSsl::EncodingFormat

Describes supported encoding formats for certificates and keys.

ConstantValueDescription
QSsl::Pem0The PEM format.
QSsl::Der1The DER format.

enum QSsl::KeyAlgorithm

Describes the different key algorithms supported by QSslKey.

ConstantValueDescription
QSsl::Rsa1The RSA algorithm.
QSsl::Dsa2The DSA algorithm.
QSsl::Ec3The Elliptic Curve algorithm.
QSsl::Dh4The Diffie-Hellman algorithm.
QSsl::Opaque0A key that should be treated as a 'black box' by QSslKey.

The opaque key facility allows applications to add support for facilities such as PKCS#11 that Qt does not currently offer natively.

enum QSsl::KeyType

Describes the two types of keys QSslKey supports.

ConstantValueDescription
QSsl::PrivateKey0A private key.
QSsl::PublicKey1A public key.

enum QSsl::SslOption
flags QSsl::SslOptions

Describes the options that can be used to control the details of SSL behaviour. These options are generally used to turn features off to work around buggy servers.

ConstantValueDescription
QSsl::SslOptionDisableEmptyFragments0x01Disables the insertion of empty fragments into the data when using block ciphers. When enabled, this prevents some attacks (such as the BEAST attack), however it is incompatible with some servers.
QSsl::SslOptionDisableSessionTickets0x02Disables the SSL session ticket extension. This can cause slower connection setup, however some servers are not compatible with the extension.
QSsl::SslOptionDisableCompression0x04Disables the SSL compression extension. When enabled, this allows the data being passed over SSL to be compressed, however some servers are not compatible with this extension.
QSsl::SslOptionDisableServerNameIndication0x08Disables the SSL server name indication extension. When enabled, this tells the server the virtual host being accessed allowing it to respond with the correct certificate.
QSsl::SslOptionDisableLegacyRenegotiation0x10Disables the older insecure mechanism for renegotiating the connection parameters. When enabled, this option can allow connections for legacy servers, but it introduces the possibility that an attacker could inject plaintext into the SSL session.
QSsl::SslOptionDisableSessionSharing0x20Disables SSL session sharing via the session ID handshake attribute.
QSsl::SslOptionDisableSessionPersistence0x40Disables storing the SSL session in ASN.1 format as returned by QSslConfiguration::sessionTicket(). Enabling this feature adds memory overhead of approximately 1K per used session ticket.
QSsl::SslOptionDisableServerCipherPreference0x80Disables selecting the cipher chosen based on the servers preferences rather than the order ciphers were sent by the client. This option is only relevant to server sockets, and is only honored by the OpenSSL backend.

By default, SslOptionDisableEmptyFragments is turned on since this causes problems with a large number of servers. SslOptionDisableLegacyRenegotiation is also turned on, since it introduces a security risk. SslOptionDisableCompression is turned on to prevent the attack publicised by CRIME. SslOptionDisableSessionPersistence is turned on to optimize memory usage. The other options are turned off.

Note: Availability of above options depends on the version of the SSL backend in use.

The SslOptions type is a typedef for QFlags<SslOption>. It stores an OR combination of SslOption values.

enum QSsl::SslProtocol

Describes the protocol of the cipher.

ConstantValueDescription
QSsl::SslV30SSLv3; not supported by QSslSocket.
QSsl::SslV21SSLv2; not supported by QSslSocket.
QSsl::TlsV1_02TLSv1.0
QSsl::TlsV1_0OrLater8TLSv1.0 and later versions. This option is not available when using the WinRT backend due to platform limitations.
QSsl::TlsV1TlsV1_0Obsolete, means the same as TlsV1_0
QSsl::TlsV1_13TLSv1.1. When using the WinRT backend this option will also enable TLSv1.0.
QSsl::TlsV1_1OrLater9TLSv1.1 and later versions. This option is not available when using the WinRT backend due to platform limitations.
QSsl::TlsV1_24TLSv1.2. When using the WinRT backend this option will also enable TLSv1.0 and TLSv1.1.
QSsl::TlsV1_2OrLater10TLSv1.2 and later versions. This option is not available when using the WinRT backend due to platform limitations.
QSsl::DtlsV1_011DTLSv1.0
QSsl::DtlsV1_0OrLater12DTLSv1.0 and later versions.
QSsl::DtlsV1_213DTLSv1.2
QSsl::DtlsV1_2OrLater14DTLSv1.2 and later versions.
QSsl::TlsV1_315TLSv1.3. (Since Qt 5.12)
QSsl::TlsV1_3OrLater16TLSv1.3 and later versions. (Since Qt 5.12)
QSsl::UnknownProtocol-1The cipher's protocol cannot be determined.
QSsl::AnyProtocol5Any supported protocol. This value is used by QSslSocket only.
QSsl::TlsV1SslV36Same as TlsV1_0. This enumerator is deprecated, use TlsV1_0 instead.
QSsl::SecureProtocolsAnyProtocol + 2The default option, using protocols known to be secure.

© 2023 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.