### Interface

# Gio DtlsConnection

since: 2.48

#### Description [src]

    interface Gio.DtlsConnection : Gio.DatagramBased

`GDtlsConnection` is the base DTLS connection class type, which wraps a `GDatagramBased` and provides DTLS encryption on top of it. Its subclasses, `GDtlsClientConnection` and `GDtlsServerConnection`, implement client-side and server-side DTLS, respectively.

For TLS support, see `GTlsConnection`.

As DTLS is datagram based, `GDtlsConnection` implements `GDatagramBased`, presenting a datagram-socket-like API for the encrypted connection. This operates over a base datagram connection, which is also a `GDatagramBased` (`GDtlsConnection:base-socket`).

To close a DTLS connection, use `g_dtls_connection_close()`.

Neither `GDtlsServerConnection` or `GDtlsClientConnection` set the peer address on their base `GDatagramBased` if it is a `GSocket` — it is up to the caller to do that if they wish. If they do not, and `g_socket_close()` is called on the base socket, the `GDtlsConnection` will not raise a `G_IO_ERROR_NOT_CONNECTED` error on further I/O.

Available since: 2.48

#### Prerequisite

In order to implement DtlsConnection, your type must inherit from`GDatagramBased`.

#### Instance methods

###### g_dtls_connection_close

Close the DTLS connection. This is equivalent to calling `g_dtls_connection_shutdown()` to shut down both sides of the connection.

since: 2.48

###### g_dtls_connection_close_async

Asynchronously close the DTLS connection. See `g_dtls_connection_close()` for more information.

since: 2.48

###### g_dtls_connection_close_finish

Finish an asynchronous TLS close operation. See `g_dtls_connection_close()` for more information.

since: 2.48

###### g_dtls_connection_emit_accept_certificate

Used by `GDtlsConnection` implementations to emit the `GDtlsConnection::accept-certificate` signal.

since: 2.48

###### g_dtls_connection_get_certificate

Gets `conn`‘s certificate, as set by g_dtls_connection_set_certificate().

since: 2.48

###### g_dtls_connection_get_channel_binding_data

Query the TLS backend for TLS channel binding data of `type` for `conn`.

since: 2.66

###### g_dtls_connection_get_ciphersuite_name

Returns the name of the current DTLS ciphersuite, or `NULL` 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.

since: 2.70

###### g_dtls_connection_get_database

Gets the certificate database that `conn` uses to verify peer certificates. See g_dtls_connection_set_database().

since: 2.48

###### g_dtls_connection_get_interaction

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 `NULL` is returned, then no user interaction will occur for this connection.

since: 2.48

###### g_dtls_connection_get_negotiated_protocol

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

since: 2.60

###### g_dtls_connection_get_peer_certificate

Gets `conn`‘s peer’s certificate after the handshake has completed or failed. (It is not set during the emission of `GDtlsConnection::accept-certificate`.).

since: 2.48

###### g_dtls_connection_get_peer_certificate_errors

Gets the errors associated with validating `conn`‘s peer’s certificate, after the handshake has completed or failed. (It is not set during the emission of `GDtlsConnection::accept-certificate`.).

since: 2.48

###### g_dtls_connection_get_protocol_version

Returns the current DTLS protocol version, which may be `G_TLS_PROTOCOL_VERSION_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 `GTlsProtocolVersion`.

since: 2.70

###### g_dtls_connection_get_rehandshake_mode

Gets `conn` rehandshaking mode. See `g_dtls_connection_set_rehandshake_mode()` for details.

deprecated: 2.64. since: 2.48

###### g_dtls_connection_get_require_close_notify

Tests whether or not `conn` expects a proper TLS close notification when the connection is closed. See `g_dtls_connection_set_require_close_notify()` for details.

since: 2.48

###### g_dtls_connection_handshake

Attempts a TLS handshake on `conn`.

since: 2.48

###### g_dtls_connection_handshake_async

Asynchronously performs a TLS handshake on `conn`. See `g_dtls_connection_handshake()` for more information.

since: 2.48

###### g_dtls_connection_handshake_finish

Finish an asynchronous TLS handshake operation. See `g_dtls_connection_handshake()` for more information.

since: 2.48

###### g_dtls_connection_set_advertised_protocols

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 `g_dtls_connection_get_negotiated_protocol()` to find the negotiated protocol after the handshake. Specifying `NULL` for the the value of `protocols` will disable ALPN negotiation.

since: 2.60

###### g_dtls_connection_set_certificate

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

since: 2.48

###### g_dtls_connection_set_database

Sets the certificate database that is used to verify peer certificates. This is set to the default database by default. See g_tls_backend_get_default_database(). If set to `NULL`, then peer certificate validation will always set the `G_TLS_CERTIFICATE_UNKNOWN_CA` error (meaning `GDtlsConnection::accept-certificate` will always be emitted on client-side connections, unless that bit is not set in `GDtlsClientConnection:validation-flags`).

since: 2.48

###### g_dtls_connection_set_interaction

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

since: 2.48

###### g_dtls_connection_set_rehandshake_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.

deprecated: 2.60. since: 2.48

###### g_dtls_connection_set_require_close_notify

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

since: 2.48

###### g_dtls_connection_shutdown

Shut down part or all of a DTLS connection.

since: 2.48

###### g_dtls_connection_shutdown_async

Asynchronously shut down part or all of the DTLS connection. See `g_dtls_connection_shutdown()` for more information.

since: 2.48

###### g_dtls_connection_shutdown_finish

Finish an asynchronous TLS shutdown operation. See `g_dtls_connection_shutdown()` for more information.

since: 2.48

#### Properties

###### Gio.DtlsConnection:advertised-protocols

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

since: 2.60

###### Gio.DtlsConnection:base-socket

The `GDatagramBased` that the connection wraps. Note that this may be any implementation of `GDatagramBased`, not just a `GSocket`.

since: 2.48

###### Gio.DtlsConnection:certificate

The connection’s certificate; see g_dtls_connection_set_certificate().

since: 2.48

###### Gio.DtlsConnection:ciphersuite-name

The name of the DTLS ciphersuite in use. See g_dtls_connection_get_ciphersuite_name().

since: 2.70

###### Gio.DtlsConnection:database

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

since: 2.48

###### Gio.DtlsConnection:interaction

A `GTlsInteraction` 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.

since: 2.48

###### Gio.DtlsConnection:negotiated-protocol

The application-layer protocol negotiated during the TLS handshake. See g_dtls_connection_get_negotiated_protocol().

since: 2.60

###### Gio.DtlsConnection:peer-certificate

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 `GDtlsConnection::accept-certificate`.

since: 2.48

###### Gio.DtlsConnection:peer-certificate-errors

The errors noticed while verifying `GDtlsConnection:peer-certificate`. Normally this should be 0, but it may not be if `GDtlsClientConnection:validation-flags` is not `G_TLS_CERTIFICATE_VALIDATE_ALL`, or if `GDtlsConnection::accept-certificate` overrode the default behavior.

since: 2.48

###### Gio.DtlsConnection:protocol-version

The DTLS protocol version in use. See g_dtls_connection_get_protocol_version().

since: 2.70

###### Gio.DtlsConnection:rehandshake-mode

The rehandshaking mode. See g_dtls_connection_set_rehandshake_mode().

deprecated: 2.60 since: 2.48

###### Gio.DtlsConnection:require-close-notify

Whether or not proper TLS close notification is required. See g_dtls_connection_set_require_close_notify().

since: 2.48

#### Signals

###### Gio.DtlsConnection::accept-certificate

Emitted during the TLS handshake after the peer certificate has been received. You can examine `peer_cert`‘s certification path by calling `g_tls_certificate_get_issuer()` on it.

since: 2.48

#### Interface structure

    struct GioDtlsConnectionInterface {
      GTypeInterface g_iface;
      gboolean (* accept_certificate) (
        GDtlsConnection* connection,
        GTlsCertificate* peer_cert,
        GTlsCertificateFlags errors
      );
      gboolean (* handshake) (
        GDtlsConnection* conn,
        GCancellable* cancellable,
        GError** error
      );
      void (* handshake_async) (
        GDtlsConnection* conn,
        int io_priority,
        GCancellable* cancellable,
        GAsyncReadyCallback callback,
        gpointer user_data
      );
      gboolean (* handshake_finish) (
        GDtlsConnection* conn,
        GAsyncResult* result,
        GError** error
      );
      gboolean (* shutdown) (
        GDtlsConnection* conn,
        gboolean shutdown_read,
        gboolean shutdown_write,
        GCancellable* cancellable,
        GError** error
      );
      void (* shutdown_async) (
        GDtlsConnection* conn,
        gboolean shutdown_read,
        gboolean shutdown_write,
        int io_priority,
        GCancellable* cancellable,
        GAsyncReadyCallback callback,
        gpointer user_data
      );
      gboolean (* shutdown_finish) (
        GDtlsConnection* conn,
        GAsyncResult* result,
        GError** error
      );
      void (* set_advertised_protocols) (
        GDtlsConnection* conn,
        const gchar* const* protocols
      );
      const gchar* (* get_negotiated_protocol) (
        GDtlsConnection* conn
      );
      gboolean (* get_binding_data) (
        GDtlsConnection* conn,
        GTlsChannelBindingType type,
        GByteArray* data,
        GError** error
      );

    }

Virtual method table for a `GDtlsConnection` implementation.

###### Interface members

`g_iface` |
    GTypeInterface
| The parent interface.
`accept_certificate` |
    gboolean (* accept_certificate) (
        GDtlsConnection* connection,
        GTlsCertificate* peer_cert,
        GTlsCertificateFlags errors
      )
| Check whether to accept a certificate.
`handshake` |
    gboolean (* handshake) (
        GDtlsConnection* conn,
        GCancellable* cancellable,
        GError** error
      )
| Perform a handshake operation.
`handshake_async` |
    void (* handshake_async) (
        GDtlsConnection* conn,
        int io_priority,
        GCancellable* cancellable,
        GAsyncReadyCallback callback,
        gpointer user_data
      )
| Start an asynchronous handshake operation.
`handshake_finish` |
    gboolean (* handshake_finish) (
        GDtlsConnection* conn,
        GAsyncResult* result,
        GError** error
      )
| Finish an asynchronous handshake operation.
`shutdown` |
    gboolean (* shutdown) (
        GDtlsConnection* conn,
        gboolean shutdown_read,
        gboolean shutdown_write,
        GCancellable* cancellable,
        GError** error
      )
| Shut down one or both directions of the connection.
`shutdown_async` |
    void (* shutdown_async) (
        GDtlsConnection* conn,
        gboolean shutdown_read,
        gboolean shutdown_write,
        int io_priority,
        GCancellable* cancellable,
        GAsyncReadyCallback callback,
        gpointer user_data
      )
| Start an asynchronous shutdown operation.
`shutdown_finish` |
    gboolean (* shutdown_finish) (
        GDtlsConnection* conn,
        GAsyncResult* result,
        GError** error
      )
| Finish an asynchronous shutdown operation.
`set_advertised_protocols` |
    void (* set_advertised_protocols) (
        GDtlsConnection* conn,
        const gchar* const* protocols
      )
| Set APLN protocol list (Since: 2.60).
`get_negotiated_protocol` |
    const gchar* (* get_negotiated_protocol) (
        GDtlsConnection* conn
      )
| Get ALPN-negotiated protocol (Since: 2.60).
`get_binding_data` |
    gboolean (* get_binding_data) (
        GDtlsConnection* conn,
        GTlsChannelBindingType type,
        GByteArray* data,
        GError** error
      )
| Retrieve TLS channel binding data (Since: 2.66).

#### Virtual methods

###### Gio.DtlsConnection.accept_certificate

Check whether to accept a certificate.

###### Gio.DtlsConnection.get_binding_data

Retrieve TLS channel binding data (Since: 2.66).

###### Gio.DtlsConnection.get_negotiated_protocol

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

since: 2.60

###### Gio.DtlsConnection.handshake

Attempts a TLS handshake on `conn`.

since: 2.48

###### Gio.DtlsConnection.handshake_async

Asynchronously performs a TLS handshake on `conn`. See `g_dtls_connection_handshake()` for more information.

since: 2.48

###### Gio.DtlsConnection.handshake_finish

Finish an asynchronous TLS handshake operation. See `g_dtls_connection_handshake()` for more information.

since: 2.48

###### Gio.DtlsConnection.set_advertised_protocols

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 `g_dtls_connection_get_negotiated_protocol()` to find the negotiated protocol after the handshake. Specifying `NULL` for the the value of `protocols` will disable ALPN negotiation.

since: 2.60

###### Gio.DtlsConnection.shutdown

Shut down part or all of a DTLS connection.

since: 2.48

###### Gio.DtlsConnection.shutdown_async

Asynchronously shut down part or all of the DTLS connection. See `g_dtls_connection_shutdown()` for more information.

since: 2.48

###### Gio.DtlsConnection.shutdown_finish

Finish an asynchronous TLS shutdown operation. See `g_dtls_connection_shutdown()` for more information.

since: 2.48