quic

README

A QUIC implementation in pure Go

quic-go is an implementation of the QUIC protocol in Go. It roughly implements the IETF QUIC draft, although we don't fully support any of the draft versions at the moment.

Version compatibility

Since quic-go is under active development, there's no guarantee that two builds of different commits are interoperable. The QUIC version used in the master branch is just a placeholder, and should not be considered stable.

If you want to use quic-go as a library in other projects, please consider using a tagged release. These releases expose experimental QUIC versions, which are guaranteed to be stable.

Google QUIC

quic-go used to support both the QUIC versions supported by Google Chrome and QUIC as deployed on Google's servers, as well as IETF QUIC. Due to the divergence of the two protocols, we decided to not support both versions any more.

The master branch only supports IETF QUIC. For Google QUIC support, please refer to the gquic branch.

Guides

We currently support Go 1.12+.

Installing and updating dependencies:

go get -t -u ./...

Running tests:

go test ./...

QUIC without HTTP/3

Take a look at this echo example.

Usage

As a server

See the example server. Starting a QUIC server is very similar to the standard lib http in go:

http.Handle("/", http.FileServer(http.Dir(wwwDir)))
http3.ListenAndServeQUIC("localhost:4242", "/path/to/cert/chain.pem", "/path/to/privkey.pem", nil)

As a client

See the example client. Use a http3.RoundTripper as a Transport in a http.Client.

http.Client{
  Transport: &http3.RoundTripper{},
}

Contributing

We are always happy to welcome new contributors! We have a number of self-contained issues that are suitable for first-time contributors, they are tagged with help wanted. If you have any questions, please feel free to reach out by opening an issue or leaving a comment.

Documentation

Index

• type Config
• type ErrorCode
• type Listener
  • func Listen(conn net.PacketConn, tlsConf *tls.Config, config *Config) (Listener, error)
  • func ListenAddr(addr string, tlsConf *tls.Config, config *Config) (Listener, error)
• type ReceiveStream
• type SendStream
• type Session
  • func Dial(pconn net.PacketConn, remoteAddr net.Addr, host string, tlsConf *tls.Config, ...) (Session, error)
  • func DialAddr(addr string, tlsConf *tls.Config, config *Config) (Session, error)
  • func DialAddrContext(ctx context.Context, addr string, tlsConf *tls.Config, config *Config) (Session, error)
  • func DialContext(ctx context.Context, pconn net.PacketConn, remoteAddr net.Addr, host string, ...) (Session, error)
• type Stream
• type StreamError
• type StreamID
• type Token
• type VersionNumber

Types

type Config

type Config struct {
	// The QUIC versions that can be negotiated.
	// If not set, it uses all versions available.
	// Warning: This API should not be considered stable and will change soon.
	Versions []VersionNumber
	// The length of the connection ID in bytes.
	// It can be 0, or any value between 4 and 18.
	// If not set, the interpretation depends on where the Config is used:
	// If used for dialing an address, a 0 byte connection ID will be used.
	// If used for a server, or dialing on a packet conn, a 4 byte connection ID will be used.
	// When dialing on a packet conn, the ConnectionIDLength value must be the same for every Dial call.
	ConnectionIDLength int
	// HandshakeTimeout is the maximum duration that the cryptographic handshake may take.
	// If the timeout is exceeded, the connection is closed.
	// If this value is zero, the timeout is set to 10 seconds.
	HandshakeTimeout time.Duration
	// IdleTimeout is the maximum duration that may pass without any incoming network activity.
	// This value only applies after the handshake has completed.
	// If the timeout is exceeded, the connection is closed.
	// If this value is zero, the timeout is set to 30 seconds.
	IdleTimeout time.Duration
	// AcceptToken determines if a Token is accepted.
	// It is called with token = nil if the client didn't send a token.
	// If not set, a default verification function is used:
	// * it verifies that the address matches, and
	//   * if the token is a retry token, that it was issued within the last 5 seconds
	//   * else, that it was issued within the last 24 hours.
	// This option is only valid for the server.
	AcceptToken func(clientAddr net.Addr, token *Token) bool
	// MaxReceiveStreamFlowControlWindow is the maximum stream-level flow control window for receiving data.
	// If this value is zero, it will default to 1 MB for the server and 6 MB for the client.
	MaxReceiveStreamFlowControlWindow uint64
	// MaxReceiveConnectionFlowControlWindow is the connection-level flow control window for receiving data.
	// If this value is zero, it will default to 1.5 MB for the server and 15 MB for the client.
	MaxReceiveConnectionFlowControlWindow uint64
	// MaxIncomingStreams is the maximum number of concurrent bidirectional streams that a peer is allowed to open.
	// If not set, it will default to 100.
	// If set to a negative value, it doesn't allow any bidirectional streams.
	MaxIncomingStreams int
	// MaxIncomingUniStreams is the maximum number of concurrent unidirectional streams that a peer is allowed to open.
	// If not set, it will default to 100.
	// If set to a negative value, it doesn't allow any unidirectional streams.
	MaxIncomingUniStreams int
	// The StatelessResetKey is used to generate stateless reset tokens.
	// If no key is configured, sending of stateless resets is disabled.
	StatelessResetKey []byte
	// KeepAlive defines whether this peer will periodically send a packet to keep the connection alive.
	KeepAlive bool
}

Config contains all configuration data needed for a QUIC server or client.

type ErrorCode

type ErrorCode = protocol.ApplicationErrorCode

An ErrorCode is an application-defined error code.

type Listener

type Listener interface {
	// Close the server. All active sessions will be closed.
	Close() error
	// Addr returns the local network addr that the server is listening on.
	Addr() net.Addr
	// Accept returns new sessions. It should be called in a loop.
	Accept() (Session, error)
}

A Listener for incoming QUIC connections

func Listen

func Listen(conn net.PacketConn, tlsConf *tls.Config, config *Config) (Listener, error)

Listen listens for QUIC connections on a given net.PacketConn. A single PacketConn only be used for a single call to Listen. The PacketConn can be used for simultaneous calls to Dial. QUIC connection IDs are used for demultiplexing the different connections. The tls.Config must not be nil and must contain a certificate configuration. The quic.Config may be nil, in that case the default values will be used.

func ListenAddr

func ListenAddr(addr string, tlsConf *tls.Config, config *Config) (Listener, error)

ListenAddr creates a QUIC server listening on a given address. The tls.Config must not be nil and must contain a certificate configuration. The quic.Config may be nil, in that case the default values will be used.

type ReceiveStream

type ReceiveStream interface {
	// see Stream.StreamID
	StreamID() StreamID
	// see Stream.Read
	io.Reader
	// see Stream.CancelRead
	CancelRead(ErrorCode)
	// see Stream.SetReadDealine
	SetReadDeadline(t time.Time) error
}

A ReceiveStream is a unidirectional Receive Stream.

type SendStream

type SendStream interface {
	// see Stream.StreamID
	StreamID() StreamID
	// see Stream.Write
	io.Writer
	// see Stream.Close
	io.Closer
	// see Stream.CancelWrite
	CancelWrite(ErrorCode)
	// see Stream.Context
	Context() context.Context
	// see Stream.SetWriteDeadline
	SetWriteDeadline(t time.Time) error
}

A SendStream is a unidirectional Send Stream.

type Session

type Session interface {
	// AcceptStream returns the next stream opened by the peer, blocking until one is available.
	// If the session was closed due to a timeout, the error satisfies
	// the net.Error interface, and Timeout() will be true.
	AcceptStream() (Stream, error)
	// AcceptUniStream returns the next unidirectional stream opened by the peer, blocking until one is available.
	// If the session was closed due to a timeout, the error satisfies
	// the net.Error interface, and Timeout() will be true.
	AcceptUniStream() (ReceiveStream, error)
	// OpenStream opens a new bidirectional QUIC stream.
	// There is no signaling to the peer about new streams:
	// The peer can only accept the stream after data has been sent on the stream.
	// If the error is non-nil, it satisfies the net.Error interface.
	// When reaching the peer's stream limit, err.Temporary() will be true.
	// If the session was closed due to a timeout, Timeout() will be true.
	OpenStream() (Stream, error)
	// OpenStreamSync opens a new bidirectional QUIC stream.
	// It blocks until a new stream can be opened.
	// If the error is non-nil, it satisfies the net.Error interface.
	// If the session was closed due to a timeout, Timeout() will be true.
	OpenStreamSync() (Stream, error)
	// OpenUniStream opens a new outgoing unidirectional QUIC stream.
	// If the error is non-nil, it satisfies the net.Error interface.
	// When reaching the peer's stream limit, Temporary() will be true.
	// If the session was closed due to a timeout, Timeout() will be true.
	OpenUniStream() (SendStream, error)
	// OpenUniStreamSync opens a new outgoing unidirectional QUIC stream.
	// It blocks until a new stream can be opened.
	// If the error is non-nil, it satisfies the net.Error interface.
	// If the session was closed due to a timeout, Timeout() will be true.
	OpenUniStreamSync() (SendStream, error)
	// LocalAddr returns the local address.
	LocalAddr() net.Addr
	// RemoteAddr returns the address of the peer.
	RemoteAddr() net.Addr
	// Close the connection.
	io.Closer
	// Close the connection with an error.
	// The error string will be sent to the peer.
	CloseWithError(ErrorCode, string) error
	// The context is cancelled when the session is closed.
	// Warning: This API should not be considered stable and might change soon.
	Context() context.Context
	// ConnectionState returns basic details about the QUIC connection.
	// Warning: This API should not be considered stable and might change soon.
	ConnectionState() tls.ConnectionState
}

A Session is a QUIC connection between two peers.

func Dial

func Dial(
	pconn net.PacketConn,
	remoteAddr net.Addr,
	host string,
	tlsConf *tls.Config,
	config *Config,
) (Session, error)

Dial establishes a new QUIC connection to a server using a net.PacketConn. The same PacketConn can be used for multiple calls to Dial and Listen, QUIC connection IDs are used for demultiplexing the different connections. The host parameter is used for SNI.

func DialAddr

func DialAddr(
	addr string,
	tlsConf *tls.Config,
	config *Config,
) (Session, error)

DialAddr establishes a new QUIC connection to a server. It uses a new UDP connection and closes this connection when the QUIC session is closed. The hostname for SNI is taken from the given address.

func DialAddrContext

func DialAddrContext(
	ctx context.Context,
	addr string,
	tlsConf *tls.Config,
	config *Config,
) (Session, error)

DialAddrContext establishes a new QUIC connection to a server using the provided context. See DialAddr for details.

func DialContext

func DialContext(
	ctx context.Context,
	pconn net.PacketConn,
	remoteAddr net.Addr,
	host string,
	tlsConf *tls.Config,
	config *Config,
) (Session, error)

DialContext establishes a new QUIC connection to a server using a net.PacketConn using the provided context. See Dial for details.

type Stream

type Stream interface {
	// StreamID returns the stream ID.
	StreamID() StreamID
	// Read reads data from the stream.
	// Read can be made to time out and return a net.Error with Timeout() == true
	// after a fixed time limit; see SetDeadline and SetReadDeadline.
	// If the stream was canceled by the peer, the error implements the StreamError
	// interface, and Canceled() == true.
	// If the session was closed due to a timeout, the error satisfies
	// the net.Error interface, and Timeout() will be true.
	io.Reader
	// Write writes data to the stream.
	// Write can be made to time out and return a net.Error with Timeout() == true
	// after a fixed time limit; see SetDeadline and SetWriteDeadline.
	// If the stream was canceled by the peer, the error implements the StreamError
	// interface, and Canceled() == true.
	// If the session was closed due to a timeout, the error satisfies
	// the net.Error interface, and Timeout() will be true.
	io.Writer
	// Close closes the write-direction of the stream.
	// Future calls to Write are not permitted after calling Close.
	// It must not be called concurrently with Write.
	// It must not be called after calling CancelWrite.
	io.Closer
	// CancelWrite aborts sending on this stream.
	// Data already written, but not yet delivered to the peer is not guaranteed to be delivered reliably.
	// Write will unblock immediately, and future calls to Write will fail.
	// When called multiple times or after closing the stream it is a no-op.
	CancelWrite(ErrorCode)
	// CancelRead aborts receiving on this stream.
	// It will ask the peer to stop transmitting stream data.
	// Read will unblock immediately, and future Read calls will fail.
	// When called multiple times or after reading the io.EOF it is a no-op.
	CancelRead(ErrorCode)
	// The context is canceled as soon as the write-side of the stream is closed.
	// This happens when Close() or CancelWrite() is called, or when the peer
	// cancels the read-side of their stream.
	// Warning: This API should not be considered stable and might change soon.
	Context() context.Context
	// SetReadDeadline sets the deadline for future Read calls and
	// any currently-blocked Read call.
	// A zero value for t means Read will not time out.
	SetReadDeadline(t time.Time) error
	// SetWriteDeadline sets the deadline for future Write calls
	// and any currently-blocked Write call.
	// Even if write times out, it may return n > 0, indicating that
	// some of the data was successfully written.
	// A zero value for t means Write will not time out.
	SetWriteDeadline(t time.Time) error
	// SetDeadline sets the read and write deadlines associated
	// with the connection. It is equivalent to calling both
	// SetReadDeadline and SetWriteDeadline.
	SetDeadline(t time.Time) error
}

Stream is the interface implemented by QUIC streams

type StreamError

type StreamError interface {
	error
	Canceled() bool
	ErrorCode() ErrorCode
}

StreamError is returned by Read and Write when the peer cancels the stream.

type StreamID

type StreamID = protocol.StreamID

The StreamID is the ID of a QUIC stream.

type Token

type Token struct {
	// IsRetryToken encodes how the client received the token. There are two ways:
	// * In a Retry packet sent when trying to establish a new connection.
	// * In a NEW_TOKEN frame on a previous connection.
	IsRetryToken bool
	RemoteAddr   string
	SentTime     time.Time
}

A Token can be used to verify the ownership of the client address.

type VersionNumber

type VersionNumber = protocol.VersionNumber

A VersionNumber is a QUIC version number.