Struct Connection

pub struct Connection(/* private fields */);

Available on crate feature quic only.

A QUIC connection.

Implementations

impl Connection

pub fn local_ip(&self) -> Option<IpAddr>

The local IP address which was used when the peer established the connection.

This can be different from the address the endpoint is bound to, in case the endpoint is bound to a wildcard address like 0.0.0.0 or ::.

This will return None for clients, or when the platform does not expose this information.

pub fn remote_address(&self) -> SocketAddr

The peer’s UDP address.

Will panic if called after poll has returned Ready.

pub fn rtt(&self) -> Duration

Current best estimate of this connection’s latency (round-trip-time).

pub fn stats(&self) -> ConnectionStats

Connection statistics.

pub fn congestion_state(&self) -> Box<dyn Controller>

Current state of the congestion control algorithm. (For debugging purposes)

pub fn peer_identity(&self) -> Option<Box<Vec<CertificateDer<'static>>>>

Cryptographic identity of the peer.

pub fn export_keying_material( &self, output: &mut [u8], label: &[u8], context: &[u8], ) -> Result<(), ExportKeyingMaterialError>

Derive keying material from this connection’s TLS session secrets.

When both peers call this method with the same label and context arguments and output buffers of equal length, they will get the same sequence of bytes in output. These bytes are cryptographically strong and pseudorandom, and are suitable for use as keying material.

This function fails if called with an empty output or called prior to the handshake completing.

See RFC5705 for more information.

pub fn handshake_data(&mut self) -> Result<Box<HandshakeData>, ConnectionError>

Available on rustls only.

Parameters negotiated during the handshake.

pub fn max_datagram_size(&self) -> Option<usize>

Compute the maximum size of datagrams that may be passed to send_datagram().

Returns None if datagrams are unsupported by the peer or disabled locally.

This may change over the lifetime of a connection according to variation in the path MTU estimate. The peer can also enforce an arbitrarily small fixed limit, but if the peer’s limit is large this is guaranteed to be a little over a kilobyte at minimum.

Not necessarily the maximum size of received datagrams.

pub fn datagram_send_buffer_space(&self) -> usize

Bytes available in the outgoing datagram buffer.

When greater than zero, calling send_datagram() with a datagram of at most this size is guaranteed not to cause older datagrams to be dropped.

pub fn set_max_concurrent_uni_streams(&self, count: VarInt)

Modify the number of remotely initiated unidirectional streams that may be concurrently open.

No streams may be opened by the peer unless fewer than count are already open. Large counts increase both minimum and worst-case memory consumption.

pub fn set_receive_window(&self, receive_window: VarInt)

See quinn_proto::TransportConfig::receive_window()

pub fn set_max_concurrent_bi_streams(&self, count: VarInt)

Modify the number of remotely initiated bidirectional streams that may be concurrently open.

No streams may be opened by the peer unless fewer than count are already open. Large counts increase both minimum and worst-case memory consumption.

pub fn close(&self, error_code: VarInt, reason: &[u8])

Close the connection immediately.

Pending operations will fail immediately with ConnectionError::LocallyClosed. No more data is sent to the peer and the peer may drop buffered data upon receiving the CONNECTION_CLOSE frame.

error_code and reason are not interpreted, and are provided directly to the peer.

reason will be truncated to fit in a single packet with overhead; to improve odds that it is preserved in full, it should be kept under 1KiB.

Gracefully closing a connection

Only the peer last receiving application data can be certain that all data is delivered. The only reliable action it can then take is to close the connection, potentially with a custom error code. The delivery of the final CONNECTION_CLOSE frame is very likely if both endpoints stay online long enough, and Endpoint::shutdown() can be used to provide sufficient time. Otherwise, the remote peer will time out the connection, provided that the idle timeout is not disabled.

The sending side can not guarantee all stream data is delivered to the remote application. It only knows the data is delivered to the QUIC stack of the remote endpoint. Once the local side sends a CONNECTION_CLOSE frame in response to calling close() the remote endpoint may drop any data it received but is as yet undelivered to the application, including data that was acknowledged as received to the local endpoint.

pub async fn closed(&self) -> ConnectionError

Wait for the connection to be closed for any reason.

pub fn close_reason(&self) -> Option<ConnectionError>

If the connection is closed, the reason why.

Returns None if the connection is still open.

pub async fn recv_datagram(&self) -> Result<Bytes, ConnectionError>

Receive an application datagram.

pub fn send_datagram(&self, data: Bytes) -> Result<(), SendDatagramError>

Transmit data as an unreliable, unordered application datagram.

Application datagrams are a low-level primitive. They may be lost or delivered out of order, and data must both fit inside a single QUIC packet and be smaller than the maximum dictated by the peer.

pub async fn send_datagram_wait( &self, data: Bytes, ) -> Result<(), SendDatagramError>

Transmit data as an unreliable, unordered application datagram.

Unlike send_datagram(), this method will wait for buffer space during congestion conditions, which effectively prioritizes old datagrams over new datagrams.

See send_datagram() for details.

pub fn open_uni(&self) -> Result<SendStream, OpenStreamError>

Initiate a new outgoing unidirectional stream.

Streams are cheap and instantaneous to open. As a consequence, the peer won’t be notified that a stream has been opened until the stream is actually used.

pub async fn open_uni_wait(&self) -> Result<SendStream, ConnectionError>

Initiate a new outgoing unidirectional stream.

Unlike open_uni(), this method will wait for the connection to allow a new stream to be opened.

See open_uni() for details.

pub fn open_bi(&self) -> Result<(SendStream, RecvStream), OpenStreamError>

Initiate a new outgoing bidirectional stream.

Streams are cheap and instantaneous to open. As a consequence, the peer won’t be notified that a stream has been opened until the stream is actually used.

pub async fn open_bi_wait( &self, ) -> Result<(SendStream, RecvStream), ConnectionError>

Initiate a new outgoing bidirectional stream.

Unlike open_bi(), this method will wait for the connection to allow a new stream to be opened.

See open_bi() for details.

pub async fn accept_uni(&self) -> Result<RecvStream, ConnectionError>

Accept the next incoming uni-directional stream

pub async fn accept_bi( &self, ) -> Result<(SendStream, RecvStream), ConnectionError>

Accept the next incoming bidirectional stream

Important Note: The Connection that calls open_bi() must write to its SendStream before the other Connection is able to accept_bi(). Calling open_bi() then waiting on the RecvStream without writing anything to SendStream will never succeed.

pub async fn accepted_0rtt(&self) -> Result<bool, ConnectionError>

Wait for the connection to be fully established.

For clients, the resulting value indicates if 0-RTT was accepted. For servers, the resulting value is meaningless.

Trait Implementations

impl Clone for Connection

fn clone(&self) -> Connection

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<B> Connection<B> for Connection

where B: Buf,

type AcceptError = ConnectionError

Error type yielded by these trait methods

type OpenStreams = OpenStreams

A producer of outgoing Unidirectional and Bidirectional streams.

type RecvStream = RecvStream

The type produced by poll_accept_recv()

fn poll_accept_recv( &mut self, cx: &mut Context<'_>, ) -> Poll<Result<Option<<Connection as Connection<B>>::RecvStream>, <Connection as Connection<B>>::AcceptError>>

Accept an incoming unidirectional stream

fn poll_accept_bidi( &mut self, cx: &mut Context<'_>, ) -> Poll<Result<Option<<Connection as OpenStreams<B>>::BidiStream>, <Connection as Connection<B>>::AcceptError>>

Accept an incoming bidirectional stream

fn opener(&self) -> <Connection as Connection<B>>::OpenStreams

Get an object to open outgoing streams.

impl Debug for Connection

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Drop for Connection

fn drop(&mut self)

Executes the destructor for this type.

impl<B> OpenStreams<B> for Connection

where B: Buf,

type BidiStream = BidiStream<B>

The type produced by poll_open_bidi()

type OpenError = ConnectionError

Error type yielded by these trait methods

type SendStream = SendStream<B>

The type produced by poll_open_send()

fn poll_open_bidi( &mut self, cx: &mut Context<'_>, ) -> Poll<Result<<Connection as OpenStreams<B>>::BidiStream, <Connection as OpenStreams<B>>::OpenError>>

Poll the connection to create a new bidirectional stream.

fn poll_open_send( &mut self, cx: &mut Context<'_>, ) -> Poll<Result<<Connection as OpenStreams<B>>::SendStream, <Connection as OpenStreams<B>>::OpenError>>

Poll the connection to create a new unidirectional stream.

fn close(&mut self, code: Code, reason: &[u8])

Close the connection immediately

impl PartialEq for Connection

fn eq(&self, other: &Connection) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl RecvDatagramExt for Connection

type Buf = Bytes

The type of Buf for raw datagrams (without the stream_id decoded)

type Error = ConnectionError

The error type that can occur when receiving a datagram

fn poll_accept_datagram( &mut self, cx: &mut Context<'_>, ) -> Poll<Result<Option<<Connection as RecvDatagramExt>::Buf>, <Connection as RecvDatagramExt>::Error>>

Poll the connection for incoming datagrams.

impl<B> SendDatagramExt<B> for Connection

where B: Buf,

type Error = SendDatagramError

The error type that can occur when sending a datagram

fn send_datagram( &mut self, data: Datagram<B>, ) -> Result<(), <Connection as SendDatagramExt<B>>::Error>

Send a datagram

impl Eq for Connection