Gio.TlsConnection¶

Subclasses:: None

Methods¶

Inherited:: Gio.IOStream (11), GObject.Object (37)
Structs:: GObject.ObjectClass (5)

	`emit_accept_certificate` (peer_cert, errors)
	`get_certificate` ()
	`get_channel_binding_data` (type)
	`get_ciphersuite_name` ()
	`get_database` ()
	`get_interaction` ()
	`get_negotiated_protocol` ()
	`get_peer_certificate` ()
	`get_peer_certificate_errors` ()
	`get_protocol_version` ()
	`get_rehandshake_mode` ()
	`get_require_close_notify` ()
	`get_use_system_certdb` ()
	`handshake` (cancellable)
	`handshake_async` (io_priority, cancellable, callback, *user_data)
	`handshake_finish` (result)
	`set_advertised_protocols` (protocols)
	`set_certificate` (certificate)
	`set_database` (database)
	`set_interaction` (interaction)
	`set_rehandshake_mode` (mode)
	`set_require_close_notify` (require_close_notify)
	`set_use_system_certdb` (use_system_certdb)

Virtual Methods¶

Inherited:: Gio.IOStream (5), GObject.Object (7)

	`do_accept_certificate` (peer_cert, errors)
	`do_get_binding_data` (type, data)
	`do_get_negotiated_protocol` ()
	`do_handshake` (cancellable)
	`do_handshake_async` (io_priority, cancellable, callback, *user_data)
	`do_handshake_finish` (result)

Properties¶

Inherited:: Gio.IOStream (3)

Name	Type	Flags	Short Description
`advertised-protocols`	[`str`]	r/w	Application-layer protocols available on this connection
`base-io-stream`	`Gio.IOStream`	r/w/co	The `Gio.IOStream` that the connection wraps
`certificate`	`Gio.TlsCertificate`	r/w	The connection’s certificate
`ciphersuite-name`	`str`	r	Name of ciphersuite negotiated for this connection
`database`	`Gio.TlsDatabase`	r/w	Certificate database to use for looking up or verifying certificates
`interaction`	`Gio.TlsInteraction`	r/w	Optional object for user interaction
`negotiated-protocol`	`str`	r	Application-layer protocol negotiated for this connection
`peer-certificate`	`Gio.TlsCertificate`	r	The connection’s peer’s certificate
`peer-certificate-errors`	`Gio.TlsCertificateFlags`	r	Errors found with the peer’s certificate
`protocol-version`	`Gio.TlsProtocolVersion`	r	TLS protocol version negotiated for this connection
`rehandshake-mode`	`Gio.TlsRehandshakeMode`	d/r/w/c	When to allow rehandshaking `deprecated`
`require-close-notify`	`bool`	r/w/c	Whether to require proper TLS close notification
`use-system-certdb`	`bool`	d/r/w/c	Whether to verify peer certificates against the system certificate database `deprecated`

Signals¶

Inherited:: GObject.Object (1)

Name	Short Description
`accept-certificate`	Emitted during the TLS handshake after the peer certificate has been received.

Fields¶

Inherited:: GObject.Object (1)

Name	Type	Access	Description
parent_instance	`Gio.IOStream`	r

Class Details¶

class Gio.TlsConnection(**kwargs)¶

Bases:: Gio.IOStream
Abstract:: Yes
Structure:: Gio.TlsConnectionClass

Gio.TlsConnection is the base TLS connection class type, which wraps a Gio.IOStream and provides TLS encryption on top of it. Its subclasses, Gio.TlsClientConnection and Gio.TlsServerConnection, implement client-side and server-side TLS, respectively.

For DTLS (Datagram TLS) support, see Gio.DtlsConnection.

New in version 2.28.

emit_accept_certificate(peer_cert, errors)[source]¶

Parameters:

peer_cert (Gio.TlsCertificate) – the peer’s Gio.TlsCertificate
errors (Gio.TlsCertificateFlags) – the problems with peer_cert

Returns:

True if one of the signal handlers has returned True to accept peer_cert

Return type:

bool

Used by Gio.TlsConnection implementations to emit the Gio.TlsConnection ::accept-certificate signal.

New in version 2.28.

get_certificate()[source]¶

Returns:: self's certificate, or None
Return type:: Gio.TlsCertificate or None

Gets self's certificate, as set by Gio.TlsConnection.set_certificate().

New in version 2.28.

get_channel_binding_data(type)[source]¶

Parameters:

type (Gio.TlsChannelBindingType) – Gio.TlsChannelBindingType type of data to fetch

Raises:

GLib.Error

Returns:

True on success, False otherwise

data:: GLib.ByteArray is filled with the binding data, or None

Return type:

(bool, data: bytes)

Query the TLS backend for TLS channel binding data of type for self.

This call retrieves TLS channel binding data as specified in RFC 5056, RFC 5929, and related RFCs. The binding data is returned in data. The data is resized by the callee using GLib.ByteArray buffer management and will be freed when the data is destroyed by GLib.ByteArray.unref(). If data is None, it will only check whether TLS backend is able to fetch the data (e.g. whether type is supported by the TLS backend). It does not guarantee that the data will be available though. That could happen if TLS connection does not support type or the binding data is not available yet due to additional negotiation or input required.

New in version 2.66.

get_ciphersuite_name()[source]¶

Returns:: The name of the current TLS ciphersuite, or None
Return type:: str or None

Returns the name of the current TLS ciphersuite, or None if the connection has not handshaked or has been closed. Beware that the TLS backend may use any of multiple different naming conventions, because OpenSSL and GnuTLS have their own ciphersuite naming conventions that are different from each other and different from the standard, IANA- registered ciphersuite names. The ciphersuite name is intended to be displayed to the user for informative purposes only, and parsing it is not recommended.

New in version 2.70.

get_database()[source]¶

Returns:: the certificate database that self uses or None
Return type:: Gio.TlsDatabase or None

Gets the certificate database that self uses to verify peer certificates. See Gio.TlsConnection.set_database().

New in version 2.30.

get_interaction()[source]¶

Returns:: The interaction object.
Return type:: Gio.TlsInteraction or None

Get the object that will be used to interact with the user. It will be used for things like prompting the user for passwords. If None is returned, then no user interaction will occur for this connection.

New in version 2.30.

get_negotiated_protocol()[source]¶

Returns:: the negotiated protocol, or None
Return type:: str or None

Gets the name of the application-layer protocol negotiated during the handshake.

If the peer did not use the ALPN extension, or did not advertise a protocol that matched one of self's protocols, or the TLS backend does not support ALPN, then this will be None. See Gio.TlsConnection.set_advertised_protocols().

New in version 2.60.

get_peer_certificate()[source]¶

Returns:: self's peer’s certificate, or None
Return type:: Gio.TlsCertificate or None

Gets self's peer’s certificate after the handshake has completed or failed. (It is not set during the emission of Gio.TlsConnection ::accept-certificate.)

New in version 2.28.

get_peer_certificate_errors()[source]¶

Returns:: self's peer’s certificate errors
Return type:: Gio.TlsCertificateFlags

Gets the errors associated with validating self's peer’s certificate, after the handshake has completed or failed. (It is not set during the emission of Gio.TlsConnection ::accept-certificate.)

See Gio.TlsConnection :peer-certificate-errors for more information.

New in version 2.28.

get_protocol_version()[source]¶

Returns:: The current TLS protocol version
Return type:: Gio.TlsProtocolVersion

Returns the current TLS protocol version, which may be Gio.TlsProtocolVersion.UNKNOWN if the connection has not handshaked, or has been closed, or if the TLS backend has implemented a protocol version that is not a recognized Gio.TlsProtocolVersion.

New in version 2.70.

get_rehandshake_mode()[source]¶

Returns:: Gio.TlsRehandshakeMode.SAFELY
Return type:: Gio.TlsRehandshakeMode

Gets self rehandshaking mode. See Gio.TlsConnection.set_rehandshake_mode() for details.

New in version 2.28.

Deprecated since version 2.60.: Changing the rehandshake mode is no longer required for compatibility. Also, rehandshaking has been removed from the TLS protocol in TLS 1.3.

get_require_close_notify()[source]¶

Returns:: True if self requires a proper TLS close notification.
Return type:: bool

Tests whether or not self expects a proper TLS close notification when the connection is closed. See Gio.TlsConnection.set_require_close_notify() for details.

New in version 2.28.

get_use_system_certdb()[source]¶

Returns:: whether self uses the system certificate database
Return type:: bool

Gets whether self uses the system certificate database to verify peer certificates. See Gio.TlsConnection.set_use_system_certdb().

Deprecated since version 2.30: Use Gio.TlsConnection.get_database() instead

handshake(cancellable)[source]¶

Parameters:: cancellable (Gio.Cancellable or None) – a Gio.Cancellable, or None
Raises:: GLib.Error
Returns:: success or failure
Return type:: bool

Attempts a TLS handshake on self.

On the client side, it is never necessary to call this method; although the connection needs to perform a handshake after connecting (or after sending a “STARTTLS”-type command), Gio.TlsConnection will handle this for you automatically when you try to send or receive data on the connection. You can call Gio.TlsConnection.handshake() manually if you want to know whether the initial handshake succeeded or failed (as opposed to just immediately trying to use self to read or write, in which case, if it fails, it may not be possible to tell if it failed before or after completing the handshake), but beware that servers may reject client authentication after the handshake has completed, so a successful handshake does not indicate the connection will be usable.

Likewise, on the server side, although a handshake is necessary at the beginning of the communication, you do not need to call this function explicitly unless you want clearer error reporting.

Previously, calling Gio.TlsConnection.handshake() after the initial handshake would trigger a rehandshake; however, this usage was deprecated in GLib 2.60 because rehandshaking was removed from the TLS protocol in TLS 1.3. Since GLib 2.64, calling this function after the initial handshake will no longer do anything.

When using a Gio.TlsConnection created by Gio.SocketClient, the Gio.SocketClient performs the initial handshake, so calling this function manually is not recommended.

#GTlsConnection::accept_certificate may be emitted during the handshake.

New in version 2.28.

handshake_async(io_priority, cancellable, callback, *user_data)[source]¶

Parameters:

io_priority (int) – the I/O priority of the request
cancellable (Gio.Cancellable or None) – a Gio.Cancellable, or None
callback (Gio.AsyncReadyCallback or None) – callback to call when the handshake is complete
user_data (object or None) – the data to pass to the callback function

Asynchronously performs a TLS handshake on self. See Gio.TlsConnection.handshake() for more information.

New in version 2.28.

handshake_finish(result)[source]¶

Parameters:: result (Gio.AsyncResult) – a Gio.AsyncResult.
Raises:: GLib.Error
Returns:: True on success, False on failure, in which case error will be set.
Return type:: bool

Finish an asynchronous TLS handshake operation. See Gio.TlsConnection.handshake() for more information.

New in version 2.28.

set_advertised_protocols(protocols)[source]¶

Parameters:: protocols ([str] or None) – a None-terminated array of ALPN protocol names (eg, “http/1.1”, “h2”), or None

Sets the list of application-layer protocols to advertise that the caller is willing to speak on this connection. The Application-Layer Protocol Negotiation (ALPN) extension will be used to negotiate a compatible protocol with the peer; use Gio.TlsConnection.get_negotiated_protocol() to find the negotiated protocol after the handshake. Specifying None for the the value of protocols will disable ALPN negotiation.

See IANA TLS ALPN Protocol IDs for a list of registered protocol IDs.

New in version 2.60.

set_certificate(certificate)[source]¶

Parameters:: certificate (Gio.TlsCertificate) – the certificate to use for self

This sets the certificate that self will present to its peer during the TLS handshake. For a Gio.TlsServerConnection, it is mandatory to set this, and that will normally be done at construct time.

For a Gio.TlsClientConnection, this is optional. If a handshake fails with Gio.TlsError.CERTIFICATE_REQUIRED, that means that the server requires a certificate, and if you try connecting again, you should call this method first. You can call Gio.TlsClientConnection.get_accepted_cas() on the failed connection to get a list of Certificate Authorities that the server will accept certificates from.

(It is also possible that a server will allow the connection with or without a certificate; in that case, if you don’t provide a certificate, you can tell that the server requested one by the fact that Gio.TlsClientConnection.get_accepted_cas() will return non-None.)

New in version 2.28.

set_database(database)[source]¶

Parameters:: database (Gio.TlsDatabase or None) – a Gio.TlsDatabase

Sets the certificate database that is used to verify peer certificates. This is set to the default database by default. See Gio.TlsBackend.get_default_database(). If set to None, then peer certificate validation will always set the Gio.TlsCertificateFlags.UNKNOWN_CA error (meaning Gio.TlsConnection ::accept-certificate will always be emitted on client-side connections, unless that bit is not set in Gio.TlsClientConnection :validation-flags).

There are nonintuitive security implications when using a non-default database. See Gio.TlsConnection :database for details.

New in version 2.30.

set_interaction(interaction)[source]¶

Parameters:: interaction (Gio.TlsInteraction or None) – an interaction object, or None

Set the object that will be used to interact with the user. It will be used for things like prompting the user for passwords.

The interaction argument will normally be a derived subclass of Gio.TlsInteraction. None can also be provided if no user interaction should occur for this connection.

New in version 2.30.

set_rehandshake_mode(mode)[source]¶

Parameters:: mode (Gio.TlsRehandshakeMode) – the rehandshaking mode

Since GLib 2.64, changing the rehandshake mode is no longer supported and will have no effect. With TLS 1.3, rehandshaking has been removed from the TLS protocol, replaced by separate post-handshake authentication and rekey operations.

New in version 2.28.

Deprecated since version 2.60.: Changing the rehandshake mode is no longer required for compatibility. Also, rehandshaking has been removed from the TLS protocol in TLS 1.3.

set_require_close_notify(require_close_notify)[source]¶

Parameters:: require_close_notify (bool) – whether or not to require close notification

Sets whether or not self expects a proper TLS close notification before the connection is closed. If this is True (the default), then self will expect to receive a TLS close notification from its peer before the connection is closed, and will return a Gio.TlsError.EOF error if the connection is closed without proper notification (since this may indicate a network error, or man-in-the-middle attack).

In some protocols, the application will know whether or not the connection was closed cleanly based on application-level data (because the application-level data includes a length field, or is somehow self-delimiting); in this case, the close notify is redundant and sometimes omitted. (TLS 1.1 explicitly allows this; in TLS 1.0 it is technically an error, but often done anyway.) You can use Gio.TlsConnection.set_require_close_notify() to tell self to allow an “unannounced” connection close, in which case the close will show up as a 0-length read, as in a non-TLS Gio.SocketConnection, and it is up to the application to check that the data has been fully received.

Note that this only affects the behavior when the peer closes the connection; when the application calls Gio.IOStream.close() itself on self, this will send a close notification regardless of the setting of this property. If you explicitly want to do an unclean close, you can close self's Gio.TlsConnection :base-io-stream rather than closing self itself, but note that this may only be done when no other operations are pending on self or the base I/O stream.

New in version 2.28.

set_use_system_certdb(use_system_certdb)[source]¶

Parameters:: use_system_certdb (bool) – whether to use the system certificate database

Sets whether self uses the system certificate database to verify peer certificates. This is True by default. If set to False, then peer certificate validation will always set the Gio.TlsCertificateFlags.UNKNOWN_CA error (meaning Gio.TlsConnection ::accept-certificate will always be emitted on client-side connections, unless that bit is not set in Gio.TlsClientConnection :validation-flags).

Deprecated since version 2.30: Use Gio.TlsConnection.set_database() instead

do_accept_certificate(peer_cert, errors) virtual¶

Parameters:

peer_cert (Gio.TlsCertificate) –
errors (Gio.TlsCertificateFlags) –

Return type:

bool

do_get_binding_data(type, data) virtual¶

Parameters:

type (Gio.TlsChannelBindingType) –
data (bytes) –

Return type:

bool

do_get_negotiated_protocol() virtual¶

Returns:: the negotiated protocol, or None
Return type:: str or None

Gets the name of the application-layer protocol negotiated during the handshake.

If the peer did not use the ALPN extension, or did not advertise a protocol that matched one of conn's protocols, or the TLS backend does not support ALPN, then this will be None. See Gio.TlsConnection.set_advertised_protocols().

New in version 2.60.

do_handshake(cancellable) virtual¶

Parameters:: cancellable (Gio.Cancellable or None) – a Gio.Cancellable, or None
Returns:: success or failure
Return type:: bool

Attempts a TLS handshake on conn.

On the client side, it is never necessary to call this method; although the connection needs to perform a handshake after connecting (or after sending a “STARTTLS”-type command), Gio.TlsConnection will handle this for you automatically when you try to send or receive data on the connection. You can call Gio.TlsConnection.handshake() manually if you want to know whether the initial handshake succeeded or failed (as opposed to just immediately trying to use conn to read or write, in which case, if it fails, it may not be possible to tell if it failed before or after completing the handshake), but beware that servers may reject client authentication after the handshake has completed, so a successful handshake does not indicate the connection will be usable.

Likewise, on the server side, although a handshake is necessary at the beginning of the communication, you do not need to call this function explicitly unless you want clearer error reporting.

Previously, calling Gio.TlsConnection.handshake() after the initial handshake would trigger a rehandshake; however, this usage was deprecated in GLib 2.60 because rehandshaking was removed from the TLS protocol in TLS 1.3. Since GLib 2.64, calling this function after the initial handshake will no longer do anything.

When using a Gio.TlsConnection created by Gio.SocketClient, the Gio.SocketClient performs the initial handshake, so calling this function manually is not recommended.

#GTlsConnection::accept_certificate may be emitted during the handshake.

New in version 2.28.

do_handshake_async(io_priority, cancellable, callback, *user_data) virtual¶

Parameters:

io_priority (int) – the I/O priority of the request
cancellable (Gio.Cancellable or None) – a Gio.Cancellable, or None
callback (Gio.AsyncReadyCallback or None) – callback to call when the handshake is complete
user_data (object or None) – the data to pass to the callback function

Asynchronously performs a TLS handshake on conn. See Gio.TlsConnection.handshake() for more information.

New in version 2.28.

do_handshake_finish(result) virtual¶

Parameters:: result (Gio.AsyncResult) – a Gio.AsyncResult.
Returns:: True on success, False on failure, in which case error will be set.
Return type:: bool

Finish an asynchronous TLS handshake operation. See Gio.TlsConnection.handshake() for more information.

New in version 2.28.

Signal Details¶

Gio.TlsConnection.signals.accept_certificate(tls_connection, peer_cert, errors)¶

Signal Name:

accept-certificate

Flags:

RUN_LAST

Parameters:

tls_connection (Gio.TlsConnection) – The object which received the signal
peer_cert (Gio.TlsCertificate) – the peer’s Gio.TlsCertificate
errors (Gio.TlsCertificateFlags) – the problems with peer_cert.

Returns:

True to accept peer_cert (which will also immediately end the signal emission). False to allow the signal emission to continue, which will cause the handshake to fail if no one else overrides it.

Return type:

bool

Emitted during the TLS handshake after the peer certificate has been received. You can examine peer_cert's certification path by calling Gio.TlsCertificate.get_issuer() on it.

For a client-side connection, peer_cert is the server’s certificate, and the signal will only be emitted if the certificate was not acceptable according to conn's #GTlsClientConnection:validation_flags. If you would like the certificate to be accepted despite errors, return True from the signal handler. Otherwise, if no handler accepts the certificate, the handshake will fail with Gio.TlsError.BAD_CERTIFICATE.

GLib guarantees that if certificate verification fails, this signal will be emitted with at least one error will be set in errors, but it does not guarantee that all possible errors will be set. Accordingly, you may not safely decide to ignore any particular type of error. For example, it would be incorrect to ignore Gio.TlsCertificateFlags.EXPIRED if you want to allow expired certificates, because this could potentially be the only error flag set even if other problems exist with the certificate.

For a server-side connection, peer_cert is the certificate presented by the client, if this was requested via the server’s #GTlsServerConnection:authentication_mode. On the server side, the signal is always emitted when the client presents a certificate, and the certificate will only be accepted if a handler returns True.

Note that if this signal is emitted as part of asynchronous I/O in the main thread, then you should not attempt to interact with the user before returning from the signal handler. If you want to let the user decide whether or not to accept the certificate, you would have to return False from the signal handler on the first attempt, and then after the connection attempt returns a Gio.TlsError.BAD_CERTIFICATE, you can interact with the user, and if the user decides to accept the certificate, remember that fact, create a new connection, and return True from the signal handler the next time.

If you are doing I/O in another thread, you do not need to worry about this, and can simply block in the signal handler until the UI thread returns an answer.

New in version 2.28.

Property Details¶

Gio.TlsConnection.props.advertised_protocols¶

Name:: advertised-protocols
Type:: [str]
Default Value:: []
Flags:: READABLE, WRITABLE

The list of application-layer protocols that the connection advertises that it is willing to speak. See Gio.TlsConnection.set_advertised_protocols().

New in version 2.60.

Gio.TlsConnection.props.base_io_stream¶

Name:: base-io-stream
Type:: Gio.IOStream
Default Value:: None
Flags:: READABLE, WRITABLE, CONSTRUCT_ONLY

The Gio.IOStream that the connection wraps. The connection holds a reference to this stream, and may run operations on the stream from other threads throughout its lifetime. Consequently, after the Gio.IOStream has been constructed, application code may only run its own operations on this stream when no Gio.IOStream operations are running.

New in version 2.28.

Gio.TlsConnection.props.certificate¶

Name:: certificate
Type:: Gio.TlsCertificate
Default Value:: None
Flags:: READABLE, WRITABLE

The connection’s certificate; see Gio.TlsConnection.set_certificate().

New in version 2.28.

Gio.TlsConnection.props.ciphersuite_name¶

Name:: ciphersuite-name
Type:: str
Default Value:: None
Flags:: READABLE

The name of the TLS ciphersuite in use. See Gio.TlsConnection.get_ciphersuite_name().

New in version 2.70.

Gio.TlsConnection.props.database¶

Name:: database
Type:: Gio.TlsDatabase
Default Value:: None
Flags:: READABLE, WRITABLE

The certificate database to use when verifying this TLS connection. If no certificate database is set, then the default database will be used. See Gio.TlsBackend.get_default_database().

When using a non-default database, Gio.TlsConnection must fall back to using the Gio.TlsDatabase to perform certificate verification using Gio.TlsDatabase.verify_chain(), which means certificate verification will not be able to make use of TLS session context. This may be less secure. For example, if you create your own Gio.TlsDatabase that just wraps the default Gio.TlsDatabase, you might expect that you have not changed anything, but this is not true because you may have altered the behavior of Gio.TlsConnection by causing it to use Gio.TlsDatabase.verify_chain(). See the documentation of Gio.TlsDatabase.verify_chain() for more details on specific security checks that may not be performed. Accordingly, setting a non-default database is discouraged except for specialty applications with unusual security requirements.

New in version 2.30.

Gio.TlsConnection.props.interaction¶

Name:: interaction
Type:: Gio.TlsInteraction
Default Value:: None
Flags:: READABLE, WRITABLE

A Gio.TlsInteraction object to be used when the connection or certificate database need to interact with the user. This will be used to prompt the user for passwords where necessary.

New in version 2.30.

Gio.TlsConnection.props.negotiated_protocol¶

Name:: negotiated-protocol
Type:: str
Default Value:: None
Flags:: READABLE

The application-layer protocol negotiated during the TLS handshake. See Gio.TlsConnection.get_negotiated_protocol().

New in version 2.60.

Gio.TlsConnection.props.peer_certificate¶

Name:: peer-certificate
Type:: Gio.TlsCertificate
Default Value:: None
Flags:: READABLE

The connection’s peer’s certificate, after the TLS handshake has completed or failed. Note in particular that this is not yet set during the emission of Gio.TlsConnection ::accept-certificate.

(You can watch for a GObject.Object ::notify signal on this property to detect when a handshake has occurred.)

New in version 2.28.

Gio.TlsConnection.props.peer_certificate_errors¶

Name:: peer-certificate-errors
Type:: Gio.TlsCertificateFlags
Default Value:: Gio.TlsCertificateFlags.NO_FLAGS
Flags:: READABLE

The errors noticed while verifying Gio.TlsConnection :peer-certificate. Normally this should be 0, but it may not be if Gio.TlsClientConnection :validation-flags is not Gio.TlsCertificateFlags.VALIDATE_ALL, or if Gio.TlsConnection ::accept-certificate overrode the default behavior.

GLib guarantees that if certificate verification fails, at least one error will be set, but it does not guarantee that all possible errors will be set. Accordingly, you may not safely decide to ignore any particular type of error. For example, it would be incorrect to mask Gio.TlsCertificateFlags.EXPIRED if you want to allow expired certificates, because this could potentially be the only error flag set even if other problems exist with the certificate.

New in version 2.28.

Gio.TlsConnection.props.protocol_version¶