updated websocket lib

vendor/github.com/gorilla/websocket/.gitignore

@@ -1,22 +0,0 @@
-# Compiled Object files, Static and Dynamic libs (Shared Objects)
-*.o
-*.a
-*.so
-
-# Folders
-_obj
-_test
-
-# Architecture specific extensions/prefixes
-*.[568vq]
-[568vq].out
-
-*.cgo1.go
-*.cgo2.c
-_cgo_defun.c
-_cgo_gotypes.go
-_cgo_export.*
-
-_testmain.go
-
-*.exe

vendor/github.com/gorilla/websocket/.travis.yml

@@ -1,20 +0,0 @@
-language: go
-sudo: false
-
-matrix:
-  include:
-    - go: 1.2
-    - go: 1.3
-    - go: 1.4
-    - go: 1.5
-    - go: 1.6
-    - go: tip
-
-install:
-  - go get golang.org/x/tools/cmd/vet
-
-script:
-  - go get -t -v ./...
-  - diff -u <(echo -n) <(gofmt -d .)
-  - go vet .
-  - go test -v -race ./...

vendor/github.com/gorilla/websocket/README.md

@@ -3,6 +3,9 @@
 Gorilla WebSocket is a [Go](http://golang.org/) implementation of the
 [WebSocket](http://www.rfc-editor.org/rfc/rfc6455.txt) protocol.
 
+[![Build Status](https://travis-ci.org/gorilla/websocket.svg?branch=master)](https://travis-ci.org/gorilla/websocket)
+[![GoDoc](https://godoc.org/github.com/gorilla/websocket?status.svg)](https://godoc.org/github.com/gorilla/websocket)
+
 ### Documentation
 
 * [API Reference](http://godoc.org/github.com/gorilla/websocket)
@@ -43,7 +46,7 @@ subdirectory](https://github.com/gorilla/websocket/tree/master/examples/autobahn
 <tr><td>Send <a href="https://tools.ietf.org/html/rfc6455#section-5.5.2">pings</a> and receive <a href="https://tools.ietf.org/html/rfc6455#section-5.5.3">pongs</a></td><td><a href="http://godoc.org/github.com/gorilla/websocket#hdr-Control_Messages">Yes</a></td><td>No</td></tr>
 <tr><td>Get the <a href="https://tools.ietf.org/html/rfc6455#section-5.6">type</a> of a received data message</td><td>Yes</td><td>Yes, see note 2</td></tr>
 <tr><td colspan="3">Other Features</tr></td>
-<tr><td>Limit size of received message</td><td><a href="http://godoc.org/github.com/gorilla/websocket#Conn.SetReadLimit">Yes</a></td><td><a href="https://code.google.com/p/go/issues/detail?id=5082">No</a></td></tr>
+<tr><td><a href="https://tools.ietf.org/html/rfc7692">Compression Extensions</a></td><td>Experimental</td><td>No</td></tr>
 <tr><td>Read message using io.Reader</td><td><a href="http://godoc.org/github.com/gorilla/websocket#Conn.NextReader">Yes</a></td><td>No, see note 3</td></tr>
 <tr><td>Write message using io.WriteCloser</td><td><a href="http://godoc.org/github.com/gorilla/websocket#Conn.NextWriter">Yes</a></td><td>No, see note 3</td></tr>
 </table>

vendor/github.com/gorilla/websocket/client.go

@@ -23,6 +23,8 @@ import (
 // invalid.
 var ErrBadHandshake = errors.New("websocket: bad handshake")
 
+var errInvalidCompression = errors.New("websocket: invalid compression negotiation")
+
 // NewClient creates a new client connection using the given net connection.
 // The URL u specifies the host and request URI. Use requestHeader to specify
 // the origin (Origin), subprotocols (Sec-WebSocket-Protocol) and cookies
@@ -70,6 +72,17 @@ type Dialer struct {
 
 	// Subprotocols specifies the client's requested subprotocols.
 	Subprotocols []string
+
+	// EnableCompression specifies if the client should attempt to negotiate
+	// per message compression (RFC 7692). Setting this value to true does not
+	// guarantee that compression will be supported. Currently only "no context
+	// takeover" modes are supported.
+	EnableCompression bool
+
+	// Jar specifies the cookie jar.
+	// If Jar is nil, cookies are not sent in requests and ignored
+	// in responses.
+	Jar http.CookieJar
 }
 
 var errMalformedURL = errors.New("malformed ws or wss URL")
@@ -83,7 +96,6 @@ func parseURL(s string) (*url.URL, error) {
 	//
 	// ws-URI = "ws:" "//" host [ ":" port ] path [ "?" query ]
 	// wss-URI = "wss:" "//" host [ ":" port ] path [ "?" query ]
-
 	var u url.URL
 	switch {
 	case strings.HasPrefix(s, "ws://"):
@@ -193,6 +205,13 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 		Host:       u.Host,
 	}
 
+	// Set the cookies present in the cookie jar of the dialer
+	if d.Jar != nil {
+		for _, cookie := range d.Jar.Cookies(u) {
+			req.AddCookie(cookie)
+		}
+	}
+
 	// Set the request headers using the capitalization for names and values in
 	// RFC examples. Although the capitalization shouldn't matter, there are
 	// servers that depend on it. The Header.Set method is not used because the
@@ -214,6 +233,7 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 			k == "Connection" ||
 			k == "Sec-Websocket-Key" ||
 			k == "Sec-Websocket-Version" ||
+			k == "Sec-Websocket-Extensions" ||
 			(k == "Sec-Websocket-Protocol" && len(d.Subprotocols) > 0):
 			return nil, nil, errors.New("websocket: duplicate header not allowed: " + k)
 		default:
@@ -221,6 +241,10 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 		}
 	}
 
+	if d.EnableCompression {
+		req.Header.Set("Sec-Websocket-Extensions", "permessage-deflate; server_no_context_takeover; client_no_context_takeover")
+	}
+
 	hostPort, hostNoPort := hostPortNoPort(u)
 
 	var proxyURL *url.URL
@@ -298,12 +322,8 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 	}
 
 	if u.Scheme == "https" {
-		cfg := d.TLSClientConfig
-		if cfg == nil {
-			cfg = &tls.Config{ServerName: hostNoPort}
-		} else if cfg.ServerName == "" {
-			shallowCopy := *cfg
-			cfg = &shallowCopy
+		cfg := cloneTLSConfig(d.TLSClientConfig)
+		if cfg.ServerName == "" {
 			cfg.ServerName = hostNoPort
 		}
 		tlsConn := tls.Client(netConn, cfg)
@@ -328,6 +348,13 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 	if err != nil {
 		return nil, nil, err
 	}
+
+	if d.Jar != nil {
+		if rc := resp.Cookies(); len(rc) > 0 {
+			d.Jar.SetCookies(u, rc)
+		}
+	}
+
 	if resp.StatusCode != 101 ||
 		!strings.EqualFold(resp.Header.Get("Upgrade"), "websocket") ||
 		!strings.EqualFold(resp.Header.Get("Connection"), "upgrade") ||
@@ -341,6 +368,20 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 		return nil, resp, ErrBadHandshake
 	}
 
+	for _, ext := range parseExtensions(req.Header) {
+		if ext[""] != "permessage-deflate" {
+			continue
+		}
+		_, snct := ext["server_no_context_takeover"]
+		_, cnct := ext["client_no_context_takeover"]
+		if !snct || !cnct {
+			return nil, resp, errInvalidCompression
+		}
+		conn.newCompressionWriter = compressNoContextTakeover
+		conn.newDecompressionReader = decompressNoContextTakeover
+		break
+	}
+
 	resp.Body = ioutil.NopCloser(bytes.NewReader([]byte{}))
 	conn.subprotocol = resp.Header.Get("Sec-Websocket-Protocol")
 
@@ -348,3 +389,32 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re
 	netConn = nil // to avoid close in defer.
 	return conn, resp, nil
 }
+
+// cloneTLSConfig clones all public fields except the fields
+// SessionTicketsDisabled and SessionTicketKey. This avoids copying the
+// sync.Mutex in the sync.Once and makes it safe to call cloneTLSConfig on a
+// config in active use.
+func cloneTLSConfig(cfg *tls.Config) *tls.Config {
+	if cfg == nil {
+		return &tls.Config{}
+	}
+	return &tls.Config{
+		Rand:                     cfg.Rand,
+		Time:                     cfg.Time,
+		Certificates:             cfg.Certificates,
+		NameToCertificate:        cfg.NameToCertificate,
+		GetCertificate:           cfg.GetCertificate,
+		RootCAs:                  cfg.RootCAs,
+		NextProtos:               cfg.NextProtos,
+		ServerName:               cfg.ServerName,
+		ClientAuth:               cfg.ClientAuth,
+		ClientCAs:                cfg.ClientCAs,
+		InsecureSkipVerify:       cfg.InsecureSkipVerify,
+		CipherSuites:             cfg.CipherSuites,
+		PreferServerCipherSuites: cfg.PreferServerCipherSuites,
+		ClientSessionCache:       cfg.ClientSessionCache,
+		MinVersion:               cfg.MinVersion,
+		MaxVersion:               cfg.MaxVersion,
+		CurvePreferences:         cfg.CurvePreferences,
+	}
+}

vendor/github.com/gorilla/websocket/compression.go

@@ -0,0 +1,105 @@
+// Copyright 2017 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package websocket
+
+import (
+	"compress/flate"
+	"errors"
+	"io"
+	"strings"
+	"sync"
+)
+
+var (
+	flateWriterPool = sync.Pool{}
+)
+
+func decompressNoContextTakeover(r io.Reader) io.Reader {
+	const tail =
+	// Add four bytes as specified in RFC
+	"\x00\x00\xff\xff" +
+		// Add final block to squelch unexpected EOF error from flate reader.
+		"\x01\x00\x00\xff\xff"
+	return flate.NewReader(io.MultiReader(r, strings.NewReader(tail)))
+}
+
+func compressNoContextTakeover(w io.WriteCloser) (io.WriteCloser, error) {
+	tw := &truncWriter{w: w}
+	i := flateWriterPool.Get()
+	var fw *flate.Writer
+	var err error
+	if i == nil {
+		fw, err = flate.NewWriter(tw, 3)
+	} else {
+		fw = i.(*flate.Writer)
+		fw.Reset(tw)
+	}
+	return &flateWrapper{fw: fw, tw: tw}, err
+}
+
+// truncWriter is an io.Writer that writes all but the last four bytes of the
+// stream to another io.Writer.
+type truncWriter struct {
+	w io.WriteCloser
+	n int
+	p [4]byte
+}
+
+func (w *truncWriter) Write(p []byte) (int, error) {
+	n := 0
+
+	// fill buffer first for simplicity.
+	if w.n < len(w.p) {
+		n = copy(w.p[w.n:], p)
+		p = p[n:]
+		w.n += n
+		if len(p) == 0 {
+			return n, nil
+		}
+	}
+
+	m := len(p)
+	if m > len(w.p) {
+		m = len(w.p)
+	}
+
+	if nn, err := w.w.Write(w.p[:m]); err != nil {
+		return n + nn, err
+	}
+
+	copy(w.p[:], w.p[m:])
+	copy(w.p[len(w.p)-m:], p[len(p)-m:])
+	nn, err := w.w.Write(p[:len(p)-m])
+	return n + nn, err
+}
+
+type flateWrapper struct {
+	fw *flate.Writer
+	tw *truncWriter
+}
+
+func (w *flateWrapper) Write(p []byte) (int, error) {
+	if w.fw == nil {
+		return 0, errWriteClosed
+	}
+	return w.fw.Write(p)
+}
+
+func (w *flateWrapper) Close() error {
+	if w.fw == nil {
+		return errWriteClosed
+	}
+	err1 := w.fw.Flush()
+	flateWriterPool.Put(w.fw)
+	w.fw = nil
+	if w.tw.p != [4]byte{0, 0, 0xff, 0xff} {
+		return errors.New("websocket: internal error, unexpected bytes at end of flate stream")
+	}
+	err2 := w.tw.w.Close()
+	if err1 != nil {
+		return err1
+	}
+	return err2
+}

vendor/github.com/gorilla/websocket/conn.go

@@ -10,18 +10,27 @@ import (
 	"errors"
 	"io"
 	"io/ioutil"
-	"math/rand"
 	"net"
 	"strconv"
+	"sync"
 	"time"
+	"unicode/utf8"
 )
 
 const (
+	// Frame header byte 0 bits from Section 5.2 of RFC 6455
+	finalBit = 1 << 7
+	rsv1Bit  = 1 << 6
+	rsv2Bit  = 1 << 5
+	rsv3Bit  = 1 << 4
+
+	// Frame header byte 1 bits from Section 5.2 of RFC 6455
+	maskBit = 1 << 7
+
 	maxFrameHeaderSize         = 2 + 8 + 4 // Fixed header + length + mask
 	maxControlFramePayloadSize = 125
-	finalBit                   = 1 << 7
-	maskBit                    = 1 << 7
-	writeWait                  = time.Second
+
+	writeWait = time.Second
 
 	defaultReadBufferSize  = 4096
 	defaultWriteBufferSize = 4096
@@ -43,6 +52,8 @@ const (
 	CloseMessageTooBig           = 1009
 	CloseMandatoryExtension      = 1010
 	CloseInternalServerErr       = 1011
+	CloseServiceRestart          = 1012
+	CloseTryAgainLater           = 1013
 	CloseTLSHandshake            = 1015
 )
 
@@ -184,51 +195,65 @@ func isData(frameType int) bool {
 	return frameType == TextMessage || frameType == BinaryMessage
 }
 
-func maskBytes(key [4]byte, pos int, b []byte) int {
-	for i := range b {
-		b[i] ^= key[pos&3]
-		pos++
-	}
-	return pos & 3
+var validReceivedCloseCodes = map[int]bool{
+	// see http://www.iana.org/assignments/websocket/websocket.xhtml#close-code-number
+
+	CloseNormalClosure:           true,
+	CloseGoingAway:               true,
+	CloseProtocolError:           true,
+	CloseUnsupportedData:         true,
+	CloseNoStatusReceived:        false,
+	CloseAbnormalClosure:         false,
+	CloseInvalidFramePayloadData: true,
+	ClosePolicyViolation:         true,
+	CloseMessageTooBig:           true,
+	CloseMandatoryExtension:      true,
+	CloseInternalServerErr:       true,
+	CloseServiceRestart:          true,
+	CloseTryAgainLater:           true,
+	CloseTLSHandshake:            false,
 }
 
-func newMaskKey() [4]byte {
-	n := rand.Uint32()
-	return [4]byte{byte(n), byte(n >> 8), byte(n >> 16), byte(n >> 24)}
+func isValidReceivedCloseCode(code int) bool {
+	return validReceivedCloseCodes[code] || (code >= 3000 && code <= 4999)
 }
 
-// Conn represents a WebSocket connection.
+// The Conn type represents a WebSocket connection.
 type Conn struct {
 	conn        net.Conn
 	isServer    bool
 	subprotocol string
 
 	// Write fields
-	mu        chan bool // used as mutex to protect write to conn and closeSent
-	closeSent bool      // true if close message was sent
+	mu            chan bool // used as mutex to protect write to conn
+	writeBuf      []byte    // frame is constructed in this buffer.
+	writeDeadline time.Time
+	writer        io.WriteCloser // the current writer returned to the application
+	isWriting     bool           // for best-effort concurrent write detection
 
-	// Message writer fields.
-	writeErr       error
-	writeBuf       []byte // frame is constructed in this buffer.
-	writePos       int    // end of data in writeBuf.
-	writeFrameType int    // type of the current frame.
-	writeSeq       int    // incremented to invalidate message writers.
-	writeDeadline  time.Time
-	isWriting      bool // for best-effort concurrent write detection
+	writeErrMu sync.Mutex
+	writeErr   error
+
+	enableWriteCompression bool
+	newCompressionWriter   func(io.WriteCloser) (io.WriteCloser, error)
 
 	// Read fields
 	readErr       error
 	br            *bufio.Reader
 	readRemaining int64 // bytes remaining in current frame.
 	readFinal     bool  // true the current message has more frames.
-	readSeq       int   // incremented to invalidate message readers.
 	readLength    int64 // Message size.
 	readLimit     int64 // Maximum message size.
 	readMaskPos   int
 	readMaskKey   [4]byte
 	handlePong    func(string) error
 	handlePing    func(string) error
+	handleClose   func(int, string) error
 	readErrCount  int
+	messageReader *messageReader // the current low-level reader
+
+	readDecompress         bool // whether last read frame had RSV1 set
+	newDecompressionReader func(io.Reader) io.Reader
 }
 
 func newConn(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int) *Conn {
@@ -238,20 +263,23 @@ func newConn(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int)
 	if readBufferSize == 0 {
 		readBufferSize = defaultReadBufferSize
 	}
+	if readBufferSize < maxControlFramePayloadSize {
+		readBufferSize = maxControlFramePayloadSize
+	}
 	if writeBufferSize == 0 {
 		writeBufferSize = defaultWriteBufferSize
 	}
 
 	c := &Conn{
-		isServer:       isServer,
-		br:             bufio.NewReaderSize(conn, readBufferSize),
-		conn:           conn,
-		mu:             mu,
-		readFinal:      true,
-		writeBuf:       make([]byte, writeBufferSize+maxFrameHeaderSize),
-		writeFrameType: noFrame,
-		writePos:       maxFrameHeaderSize,
+		isServer:               isServer,
+		br:                     bufio.NewReaderSize(conn, readBufferSize),
+		conn:                   conn,
+		mu:                     mu,
+		readFinal:              true,
+		writeBuf:               make([]byte, writeBufferSize+maxFrameHeaderSize),
+		enableWriteCompression: true,
 	}
+	c.SetCloseHandler(nil)
 	c.SetPingHandler(nil)
 	c.SetPongHandler(nil)
 	return c
@@ -279,29 +307,40 @@ func (c *Conn) RemoteAddr() net.Addr {
 
 // Write methods
 
+func (c *Conn) writeFatal(err error) error {
+	err = hideTempErr(err)
+	c.writeErrMu.Lock()
+	if c.writeErr == nil {
+		c.writeErr = err
+	}
+	c.writeErrMu.Unlock()
+	return err
+}
+
 func (c *Conn) write(frameType int, deadline time.Time, bufs ...[]byte) error {
 	<-c.mu
 	defer func() { c.mu <- true }()
 
-	if c.closeSent {
-		return ErrCloseSent
-	} else if frameType == CloseMessage {
-		c.closeSent = true
+	c.writeErrMu.Lock()
+	err := c.writeErr
+	c.writeErrMu.Unlock()
+	if err != nil {
+		return err
 	}
 
 	c.conn.SetWriteDeadline(deadline)
 	for _, buf := range bufs {
 		if len(buf) > 0 {
-			n, err := c.conn.Write(buf)
-			if n != len(buf) {
-				// Close on partial write.
-				c.conn.Close()
-			}
+			_, err := c.conn.Write(buf)
 			if err != nil {
-				return err
+				return c.writeFatal(err)
 			}
 		}
 	}
+
+	if frameType == CloseMessage {
+		c.writeFatal(ErrCloseSent)
+	}
 	return nil
 }
 
@@ -350,60 +389,108 @@ func (c *Conn) WriteControl(messageType int, data []byte, deadline time.Time) er
 	}
 	defer func() { c.mu <- true }()
 
-	if c.closeSent {
-		return ErrCloseSent
-	} else if messageType == CloseMessage {
-		c.closeSent = true
+	c.writeErrMu.Lock()
+	err := c.writeErr
+	c.writeErrMu.Unlock()
+	if err != nil {
+		return err
 	}
 
 	c.conn.SetWriteDeadline(deadline)
-	n, err := c.conn.Write(buf)
-	if n != 0 && n != len(buf) {
-		c.conn.Close()
+	_, err = c.conn.Write(buf)
+	if err != nil {
+		return c.writeFatal(err)
 	}
-	return hideTempErr(err)
+	if messageType == CloseMessage {
+		c.writeFatal(ErrCloseSent)
+	}
+	return err
 }
 
-// NextWriter returns a writer for the next message to send.  The writer's
-// Close method flushes the complete message to the network.
+func (c *Conn) prepWrite(messageType int) error {
+	// Close previous writer if not already closed by the application. It's
+	// probably better to return an error in this situation, but we cannot
+	// change this without breaking existing applications.
+	if c.writer != nil {
+		c.writer.Close()
+		c.writer = nil
+	}
+
+	if !isControl(messageType) && !isData(messageType) {
+		return errBadWriteOpCode
+	}
+
+	c.writeErrMu.Lock()
+	err := c.writeErr
+	c.writeErrMu.Unlock()
+	return err
+}
+
+// NextWriter returns a writer for the next message to send. The writer's Close
+// method flushes the complete message to the network.
 //
 // There can be at most one open writer on a connection. NextWriter closes the
 // previous writer if the application has not already done so.
 func (c *Conn) NextWriter(messageType int) (io.WriteCloser, error) {
-	if c.writeErr != nil {
-		return nil, c.writeErr
+	if err := c.prepWrite(messageType); err != nil {
+		return nil, err
 	}
 
-	if c.writeFrameType != noFrame {
-		if err := c.flushFrame(true, nil); err != nil {
+	mw := &messageWriter{
+		c:         c,
+		frameType: messageType,
+		pos:       maxFrameHeaderSize,
+	}
+	c.writer = mw
+	if c.newCompressionWriter != nil && c.enableWriteCompression && isData(messageType) {
+		w, err := c.newCompressionWriter(c.writer)
+		if err != nil {
+			c.writer = nil
 			return nil, err
 		}
+		mw.compress = true
+		c.writer = w
 	}
-
-	if !isControl(messageType) && !isData(messageType) {
-		return nil, errBadWriteOpCode
-	}
-
-	c.writeFrameType = messageType
-	return messageWriter{c, c.writeSeq}, nil
+	return c.writer, nil
 }
 
-func (c *Conn) flushFrame(final bool, extra []byte) error {
-	length := c.writePos - maxFrameHeaderSize + len(extra)
+type messageWriter struct {
+	c         *Conn
+	compress  bool // whether next call to flushFrame should set RSV1
+	pos       int  // end of data in writeBuf.
+	frameType int  // type of the current frame.
+	err       error
+}
+
+func (w *messageWriter) fatal(err error) error {
+	if w.err != nil {
+		w.err = err
+		w.c.writer = nil
+	}
+	return err
+}
+
+// flushFrame writes buffered data and extra as a frame to the network. The
+// final argument indicates that this is the last frame in the message.
+func (w *messageWriter) flushFrame(final bool, extra []byte) error {
+	c := w.c
+	length := w.pos - maxFrameHeaderSize + len(extra)
 
 	// Check for invalid control frames.
-	if isControl(c.writeFrameType) &&
+	if isControl(w.frameType) &&
 		(!final || length > maxControlFramePayloadSize) {
-		c.writeSeq++
-		c.writeFrameType = noFrame
-		c.writePos = maxFrameHeaderSize
-		return errInvalidControlFrame
+		return w.fatal(errInvalidControlFrame)
 	}
 
-	b0 := byte(c.writeFrameType)
+	b0 := byte(w.frameType)
 	if final {
 		b0 |= finalBit
 	}
+	if w.compress {
+		b0 |= rsv1Bit
+	}
+	w.compress = false
+
 	b1 := byte(0)
 	if !c.isServer {
 		b1 |= maskBit
@@ -435,10 +522,9 @@ func (c *Conn) flushFrame(final bool, extra []byte) error {
 	if !c.isServer {
 		key := newMaskKey()
 		copy(c.writeBuf[maxFrameHeaderSize-4:], key[:])
-		maskBytes(key, 0, c.writeBuf[maxFrameHeaderSize:c.writePos])
+		maskBytes(key, 0, c.writeBuf[maxFrameHeaderSize:w.pos])
 		if len(extra) > 0 {
-			c.writeErr = errors.New("websocket: internal error, extra used in client mode")
-			return c.writeErr
+			return c.writeFatal(errors.New("websocket: internal error, extra used in client mode"))
 		}
 	}
 
@@ -451,46 +537,35 @@ func (c *Conn) flushFrame(final bool, extra []byte) error {
 	}
 	c.isWriting = true
 
-	c.writeErr = c.write(c.writeFrameType, c.writeDeadline, c.writeBuf[framePos:c.writePos], extra)
+	err := c.write(w.frameType, c.writeDeadline, c.writeBuf[framePos:w.pos], extra)
 
 	if !c.isWriting {
 		panic("concurrent write to websocket connection")
 	}
 	c.isWriting = false
 
-	// Setup for next frame.
-	c.writePos = maxFrameHeaderSize
-	c.writeFrameType = continuationFrame
+	if err != nil {
+		return w.fatal(err)
+	}
+
 	if final {
-		c.writeSeq++
-		c.writeFrameType = noFrame
+		c.writer = nil
+		return nil
 	}
-	return c.writeErr
-}
 
-type messageWriter struct {
-	c   *Conn
-	seq int
-}
-
-func (w messageWriter) err() error {
-	c := w.c
-	if c.writeSeq != w.seq {
-		return errWriteClosed
-	}
-	if c.writeErr != nil {
-		return c.writeErr
-	}
+	// Setup for next frame.
+	w.pos = maxFrameHeaderSize
+	w.frameType = continuationFrame
 	return nil
 }
 
-func (w messageWriter) ncopy(max int) (int, error) {
-	n := len(w.c.writeBuf) - w.c.writePos
+func (w *messageWriter) ncopy(max int) (int, error) {
+	n := len(w.c.writeBuf) - w.pos
 	if n <= 0 {
-		if err := w.c.flushFrame(false, nil); err != nil {
+		if err := w.flushFrame(false, nil); err != nil {
 			return 0, err
 		}
-		n = len(w.c.writeBuf) - w.c.writePos
+		n = len(w.c.writeBuf) - w.pos
 	}
 	if n > max {
 		n = max
@@ -498,14 +573,14 @@ func (w messageWriter) ncopy(max int) (int, error) {
 	return n, nil
 }
 
-func (w messageWriter) write(final bool, p []byte) (int, error) {
-	if err := w.err(); err != nil {
-		return 0, err
+func (w *messageWriter) Write(p []byte) (int, error) {
+	if w.err != nil {
+		return 0, w.err
 	}
 
 	if len(p) > 2*len(w.c.writeBuf) && w.c.isServer {
 		// Don't buffer large messages.
-		err := w.c.flushFrame(final, p)
+		err := w.flushFrame(false, p)
 		if err != nil {
 			return 0, err
 		}
@@ -518,20 +593,16 @@ func (w messageWriter) write(final bool, p []byte) (int, error) {
 		if err != nil {
 			return 0, err
 		}
-		copy(w.c.writeBuf[w.c.writePos:], p[:n])
-		w.c.writePos += n
+		copy(w.c.writeBuf[w.pos:], p[:n])
+		w.pos += n
 		p = p[n:]
 	}
 	return nn, nil
 }
 
-func (w messageWriter) Write(p []byte) (int, error) {
-	return w.write(false, p)
-}
-
-func (w messageWriter) WriteString(p string) (int, error) {
-	if err := w.err(); err != nil {
-		return 0, err
+func (w *messageWriter) WriteString(p string) (int, error) {
+	if w.err != nil {
+		return 0, w.err
 	}
 
 	nn := len(p)
@@ -540,27 +611,27 @@ func (w messageWriter) WriteString(p string) (int, error) {
 		if err != nil {
 			return 0, err
 		}
-		copy(w.c.writeBuf[w.c.writePos:], p[:n])
-		w.c.writePos += n
+		copy(w.c.writeBuf[w.pos:], p[:n])
+		w.pos += n
 		p = p[n:]
 	}
 	return nn, nil
 }
 
-func (w messageWriter) ReadFrom(r io.Reader) (nn int64, err error) {
-	if err := w.err(); err != nil {
-		return 0, err
+func (w *messageWriter) ReadFrom(r io.Reader) (nn int64, err error) {
+	if w.err != nil {
+		return 0, w.err
 	}
 	for {
-		if w.c.writePos == len(w.c.writeBuf) {
-			err = w.c.flushFrame(false, nil)
+		if w.pos == len(w.c.writeBuf) {
+			err = w.flushFrame(false, nil)
 			if err != nil {
 				break
 			}
 		}
 		var n int
-		n, err = r.Read(w.c.writeBuf[w.c.writePos:])
-		w.c.writePos += n
+		n, err = r.Read(w.c.writeBuf[w.pos:])
+		w.pos += n
 		nn += int64(n)
 		if err != nil {
 			if err == io.EOF {
@@ -572,30 +643,43 @@ func (w messageWriter) ReadFrom(r io.Reader) (nn int64, err error) {
 	return nn, err
 }
 
-func (w messageWriter) Close() error {
-	if err := w.err(); err != nil {
+func (w *messageWriter) Close() error {
+	if w.err != nil {
+		return w.err
+	}
+	if err := w.flushFrame(true, nil); err != nil {
 		return err
 	}
-	return w.c.flushFrame(true, nil)
+	w.err = errWriteClosed
+	return nil
 }
 
 // WriteMessage is a helper method for getting a writer using NextWriter,
 // writing the message and closing the writer.
 func (c *Conn) WriteMessage(messageType int, data []byte) error {
-	wr, err := c.NextWriter(messageType)
+
+	if c.isServer && (c.newCompressionWriter == nil || !c.enableWriteCompression) {
+
+		// Fast path with no allocations and single frame.
+
+		if err := c.prepWrite(messageType); err != nil {
+			return err
+		}
+		mw := messageWriter{c: c, frameType: messageType, pos: maxFrameHeaderSize}
+		n := copy(c.writeBuf[mw.pos:], data)
+		mw.pos += n
+		data = data[n:]
+		return mw.flushFrame(true, data)
+	}
+
+	w, err := c.NextWriter(messageType)
 	if err != nil {
 		return err
 	}
-	w := wr.(messageWriter)
-	if _, err := w.write(true, data); err != nil {
+	if _, err = w.Write(data); err != nil {
 		return err
 	}
-	if c.writeSeq == w.seq {
-		if err := c.flushFrame(true, nil); err != nil {
-			return err
-		}
-	}
-	return nil
+	return w.Close()
 }
 
 // SetWriteDeadline sets the write deadline on the underlying network
@@ -609,22 +693,6 @@ func (c *Conn) SetWriteDeadline(t time.Time) error {
 
 // Read methods
 
-// readFull is like io.ReadFull except that io.EOF is never returned.
-func (c *Conn) readFull(p []byte) (err error) {
-	var n int
-	for n < len(p) && err == nil {
-		var nn int
-		nn, err = c.br.Read(p[n:])
-		n += nn
-	}
-	if n == len(p) {
-		err = nil
-	} else if err == io.EOF {
-		err = errUnexpectedEOF
-	}
-	return
-}
-
 func (c *Conn) advanceFrame() (int, error) {
 
 	// 1. Skip remainder of previous frame.
@@ -637,19 +705,24 @@ func (c *Conn) advanceFrame() (int, error) {
 
 	// 2. Read and parse first two bytes of frame header.
 
-	var b [8]byte
-	if err := c.readFull(b[:2]); err != nil {
+	p, err := c.read(2)
+	if err != nil {
 		return noFrame, err
 	}
 
-	final := b[0]&finalBit != 0
-	frameType := int(b[0] & 0xf)
-	reserved := int((b[0] >> 4) & 0x7)
-	mask := b[1]&maskBit != 0
-	c.readRemaining = int64(b[1] & 0x7f)
+	final := p[0]&finalBit != 0
+	frameType := int(p[0] & 0xf)
+	mask := p[1]&maskBit != 0
+	c.readRemaining = int64(p[1] & 0x7f)
 
-	if reserved != 0 {
-		return noFrame, c.handleProtocolError("unexpected reserved bits " + strconv.Itoa(reserved))
+	c.readDecompress = false
+	if c.newDecompressionReader != nil && (p[0]&rsv1Bit) != 0 {
+		c.readDecompress = true
+		p[0] &^= rsv1Bit
+	}
+
+	if rsv := p[0] & (rsv1Bit | rsv2Bit | rsv3Bit); rsv != 0 {
+		return noFrame, c.handleProtocolError("unexpected reserved bits 0x" + strconv.FormatInt(int64(rsv), 16))
 	}
 
 	switch frameType {
@@ -678,15 +751,17 @@ func (c *Conn) advanceFrame() (int, error) {
 
 	switch c.readRemaining {
 	case 126:
-		if err := c.readFull(b[:2]); err != nil {
+		p, err := c.read(2)
+		if err != nil {
 			return noFrame, err
 		}
-		c.readRemaining = int64(binary.BigEndian.Uint16(b[:2]))
+		c.readRemaining = int64(binary.BigEndian.Uint16(p))
 	case 127:
-		if err := c.readFull(b[:8]); err != nil {
+		p, err := c.read(8)
+		if err != nil {
 			return noFrame, err
 		}
-		c.readRemaining = int64(binary.BigEndian.Uint64(b[:8]))
+		c.readRemaining = int64(binary.BigEndian.Uint64(p))
 	}
 
 	// 4. Handle frame masking.
@@ -697,9 +772,11 @@ func (c *Conn) advanceFrame() (int, error) {
 
 	if mask {
 		c.readMaskPos = 0
-		if err := c.readFull(c.readMaskKey[:]); err != nil {
+		p, err := c.read(len(c.readMaskKey))
+		if err != nil {
 			return noFrame, err
 		}
+		copy(c.readMaskKey[:], p)
 	}
 
 	// 5. For text and binary messages, enforce read limit and return.
@@ -719,9 +796,9 @@ func (c *Conn) advanceFrame() (int, error) {
 
 	var payload []byte
 	if c.readRemaining > 0 {
-		payload = make([]byte, c.readRemaining)
+		payload, err = c.read(int(c.readRemaining))
 		c.readRemaining = 0
-		if err := c.readFull(payload); err != nil {
+		if err != nil {
 			return noFrame, err
 		}
 		if c.isServer {
@@ -741,15 +818,21 @@ func (c *Conn) advanceFrame() (int, error) {
 			return noFrame, err
 		}
 	case CloseMessage:
-		echoMessage := []byte{}
 		closeCode := CloseNoStatusReceived
 		closeText := ""
 		if len(payload) >= 2 {
-			echoMessage = payload[:2]
 			closeCode = int(binary.BigEndian.Uint16(payload))
+			if !isValidReceivedCloseCode(closeCode) {
+				return noFrame, c.handleProtocolError("invalid close code")
+			}
 			closeText = string(payload[2:])
+			if !utf8.ValidString(closeText) {
+				return noFrame, c.handleProtocolError("invalid utf8 payload in close frame")
+			}
+		}
+		if err := c.handleClose(closeCode, closeText); err != nil {
+			return noFrame, err
 		}
-		c.WriteControl(CloseMessage, echoMessage, time.Now().Add(writeWait))
 		return noFrame, &CloseError{Code: closeCode, Text: closeText}
 	}
 
@@ -773,7 +856,7 @@ func (c *Conn) handleProtocolError(message string) error {
 // this method return the same error.
 func (c *Conn) NextReader() (messageType int, r io.Reader, err error) {
 
-	c.readSeq++
+	c.messageReader = nil
 	c.readLength = 0
 
 	for c.readErr == nil {
@@ -783,7 +866,12 @@ func (c *Conn) NextReader() (messageType int, r io.Reader, err error) {
 			break
 		}
 		if frameType == TextMessage || frameType == BinaryMessage {
-			return frameType, messageReader{c, c.readSeq}, nil
+			c.messageReader = &messageReader{c}
+			var r io.Reader = c.messageReader
+			if c.readDecompress {
+				r = c.newDecompressionReader(r)
+			}
+			return frameType, r, nil
 		}
 	}
 
@@ -798,48 +886,48 @@ func (c *Conn) NextReader() (messageType int, r io.Reader, err error) {
 	return noFrame, nil, c.readErr
 }
 
-type messageReader struct {
-	c   *Conn
-	seq int
-}
+type messageReader struct{ c *Conn }
 
-func (r messageReader) Read(b []byte) (int, error) {
-
-	if r.seq != r.c.readSeq {
+func (r *messageReader) Read(b []byte) (int, error) {
+	c := r.c
+	if c.messageReader != r {
 		return 0, io.EOF
 	}
 
-	for r.c.readErr == nil {
+	for c.readErr == nil {
 
-		if r.c.readRemaining > 0 {
-			if int64(len(b)) > r.c.readRemaining {
-				b = b[:r.c.readRemaining]
+		if c.readRemaining > 0 {
+			if int64(len(b)) > c.readRemaining {
+				b = b[:c.readRemaining]
 			}
-			n, err := r.c.br.Read(b)
-			r.c.readErr = hideTempErr(err)
-			if r.c.isServer {
-				r.c.readMaskPos = maskBytes(r.c.readMaskKey, r.c.readMaskPos, b[:n])
+			n, err := c.br.Read(b)
+			c.readErr = hideTempErr(err)
+			if c.isServer {
+				c.readMaskPos = maskBytes(c.readMaskKey, c.readMaskPos, b[:n])
 			}
-			r.c.readRemaining -= int64(n)
-			return n, r.c.readErr
+			c.readRemaining -= int64(n)
+			if c.readRemaining > 0 && c.readErr == io.EOF {
+				c.readErr = errUnexpectedEOF
+			}
+			return n, c.readErr
 		}
 
-		if r.c.readFinal {
-			r.c.readSeq++
+		if c.readFinal {
+			c.messageReader = nil
 			return 0, io.EOF
 		}
 
-		frameType, err := r.c.advanceFrame()
+		frameType, err := c.advanceFrame()
 		switch {
 		case err != nil:
-			r.c.readErr = hideTempErr(err)
+			c.readErr = hideTempErr(err)
 		case frameType == TextMessage || frameType == BinaryMessage:
-			r.c.readErr = errors.New("websocket: internal error, unexpected text or binary in Reader")
+			c.readErr = errors.New("websocket: internal error, unexpected text or binary in Reader")
 		}
 	}
 
-	err := r.c.readErr
-	if err == io.EOF && r.seq == r.c.readSeq {
+	err := c.readErr
+	if err == io.EOF && c.messageReader == r {
 		err = errUnexpectedEOF
 	}
 	return 0, err
@@ -872,6 +960,34 @@ func (c *Conn) SetReadLimit(limit int64) {
 	c.readLimit = limit
 }
 
+// CloseHandler returns the current close handler
+func (c *Conn) CloseHandler() func(code int, text string) error {
+	return c.handleClose
+}
+
+// SetCloseHandler sets the handler for close messages received from the peer.
+// The code argument to h is the received close code or CloseNoStatusReceived
+// if the close message is empty. The default close handler sends a close frame
+// back to the peer.
+func (c *Conn) SetCloseHandler(h func(code int, text string) error) {
+	if h == nil {
+		h = func(code int, text string) error {
+			message := []byte{}
+			if code != CloseNoStatusReceived {
+				message = FormatCloseMessage(code, "")
+			}
+			c.WriteControl(CloseMessage, message, time.Now().Add(writeWait))
+			return nil
+		}
+	}
+	c.handleClose = h
+}
+
+// PingHandler returns the current ping handler
+func (c *Conn) PingHandler() func(appData string) error {
+	return c.handlePing
+}
+
 // SetPingHandler sets the handler for ping messages received from the peer.
 // The appData argument to h is the PING frame application data. The default
 // ping handler sends a pong to the peer.
@@ -890,6 +1006,11 @@ func (c *Conn) SetPingHandler(h func(appData string) error) {
 	c.handlePing = h
 }
 
+// PongHandler returns the current pong handler
+func (c *Conn) PongHandler() func(appData string) error {
+	return c.handlePong
+}
+
 // SetPongHandler sets the handler for pong messages received from the peer.
 // The appData argument to h is the PONG frame application data. The default
 // pong handler does nothing.
@@ -906,6 +1027,13 @@ func (c *Conn) UnderlyingConn() net.Conn {
 	return c.conn
 }
 
+// EnableWriteCompression enables and disables write compression of
+// subsequent text and binary messages. This function is a noop if
+// compression was not negotiated with the peer.
+func (c *Conn) EnableWriteCompression(enable bool) {
+	c.enableWriteCompression = enable
+}
+
 // FormatCloseMessage formats closeCode and text as a WebSocket close message.
 func FormatCloseMessage(closeCode int, text string) []byte {
 	buf := make([]byte, 2+len(text))

vendor/github.com/gorilla/websocket/conn_read.go

@@ -0,0 +1,18 @@
+// Copyright 2016 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.5
+
+package websocket
+
+import "io"
+
+func (c *Conn) read(n int) ([]byte, error) {
+	p, err := c.br.Peek(n)
+	if err == io.EOF {
+		err = errUnexpectedEOF
+	}
+	c.br.Discard(len(p))
+	return p, err
+}

vendor/github.com/gorilla/websocket/conn_read_legacy.go

@@ -0,0 +1,21 @@
+// Copyright 2016 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !go1.5
+
+package websocket
+
+import "io"
+
+func (c *Conn) read(n int) ([]byte, error) {
+	p, err := c.br.Peek(n)
+	if err == io.EOF {
+		err = errUnexpectedEOF
+	}
+	if len(p) > 0 {
+		// advance over the bytes just read
+		io.ReadFull(c.br, p)
+	}
+	return p, err
+}

vendor/github.com/gorilla/websocket/doc.go

@@ -85,18 +85,22 @@
 // and pong. Call the connection WriteControl, WriteMessage or NextWriter
 // methods to send a control message to the peer.
 //
-// Connections handle received ping and pong messages by invoking callback
-// functions set with SetPingHandler and SetPongHandler methods. The default
-// ping handler sends a pong to the client. The callback functions can be
-// invoked from the NextReader, ReadMessage or the message Read method.
-//
 // Connections handle received close messages by sending a close message to the
 // peer and returning a *CloseError from the the NextReader, ReadMessage or the
 // message Read method.
 //
-// The application must read the connection to process ping and close messages
-// sent from the peer. If the application is not otherwise interested in
-// messages from the peer, then the application should start a goroutine to
+// Connections handle received ping and pong messages by invoking callback
+// functions set with SetPingHandler and SetPongHandler methods. The callback
+// functions are called from the NextReader, ReadMessage and the message Read
+// methods.
+//
+// The default ping handler sends a pong to the peer. The application's reading
+// goroutine can block for a short time while the handler writes the pong data
+// to the connection.
+//
+// The application must read the connection to process ping, pong and close
+// messages sent from the peer. If the application is not otherwise interested
+// in messages from the peer, then the application should start a goroutine to
 // read and discard messages from the peer. A simple example is:
 //
 //  func readLoop(c *websocket.Conn) {
@@ -145,4 +149,25 @@
 // The deprecated Upgrade function does not enforce an origin policy. It's the
 // application's responsibility to check the Origin header before calling
 // Upgrade.
+//
+// Compression [Experimental]
+//
+// Per message compression extensions (RFC 7692) are experimentally supported
+// by this package in a limited capacity. Setting the EnableCompression option
+// to true in Dialer or Upgrader will attempt to negotiate per message deflate
+// support. If compression was successfully negotiated with the connection's
+// peer, any message received in compressed form will be automatically
+// decompressed. All Read methods will return uncompressed bytes.
+//
+// Per message compression of messages written to a connection can be enabled
+// or disabled by calling the corresponding Conn method:
+//
+// conn.EnableWriteCompression(true)
+//
+// Currently this package does not support compression with "context takeover".
+// This means that messages must be compressed and decompressed in isolation,
+// without retaining sliding window or dictionary state across messages. For
+// more details refer to RFC 7692.
+//
+// Use of compression is experimental and may result in decreased performance.
 package websocket

vendor/github.com/gorilla/websocket/mask.go

@@ -0,0 +1,61 @@
+// Copyright 2016 The Gorilla WebSocket Authors. All rights reserved.  Use of
+// this source code is governed by a BSD-style license that can be found in the
+// LICENSE file.
+
+package websocket
+
+import (
+	"math/rand"
+	"unsafe"
+)
+
+const wordSize = int(unsafe.Sizeof(uintptr(0)))
+
+func newMaskKey() [4]byte {
+	n := rand.Uint32()
+	return [4]byte{byte(n), byte(n >> 8), byte(n >> 16), byte(n >> 24)}
+}
+
+func maskBytes(key [4]byte, pos int, b []byte) int {
+
+	// Mask one byte at a time for small buffers.
+	if len(b) < 2*wordSize {
+		for i := range b {
+			b[i] ^= key[pos&3]
+			pos++
+		}
+		return pos & 3
+	}
+
+	// Mask one byte at a time to word boundary.
+	if n := int(uintptr(unsafe.Pointer(&b[0]))) % wordSize; n != 0 {
+		n = wordSize - n
+		for i := range b[:n] {
+			b[i] ^= key[pos&3]
+			pos++
+		}
+		b = b[n:]
+	}
+
+	// Create aligned word size key.
+	var k [wordSize]byte
+	for i := range k {
+		k[i] = key[(pos+i)&3]
+	}
+	kw := *(*uintptr)(unsafe.Pointer(&k))
+
+	// Mask one word at a time.
+	n := (len(b) / wordSize) * wordSize
+	for i := 0; i < n; i += wordSize {
+		*(*uintptr)(unsafe.Pointer(uintptr(unsafe.Pointer(&b[0])) + uintptr(i))) ^= kw
+	}
+
+	// Mask one byte at a time for remaining bytes.
+	b = b[n:]
+	for i := range b {
+		b[i] ^= key[pos&3]
+		pos++
+	}
+
+	return pos & 3
+}

vendor/github.com/gorilla/websocket/server.go

@@ -46,6 +46,12 @@ type Upgrader struct {
 	// CheckOrigin is nil, the host in the Origin header must not be set or
 	// must match the host of the request.
 	CheckOrigin func(r *http.Request) bool
+
+	// EnableCompression specify if the server should attempt to negotiate per
+	// message compression (RFC 7692). Setting this value to true does not
+	// guarantee that compression will be supported. Currently only "no context
+	// takeover" modes are supported.
+	EnableCompression bool
 }
 
 func (u *Upgrader) returnError(w http.ResponseWriter, r *http.Request, status int, reason string) (*Conn, error) {
@@ -53,6 +59,7 @@ func (u *Upgrader) returnError(w http.ResponseWriter, r *http.Request, status in
 	if u.Error != nil {
 		u.Error(w, r, status, err)
 	} else {
+		w.Header().Set("Sec-Websocket-Version", "13")
 		http.Error(w, http.StatusText(status), status)
 	}
 	return nil, err
@@ -99,7 +106,12 @@ func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeade
 	if r.Method != "GET" {
 		return u.returnError(w, r, http.StatusMethodNotAllowed, "websocket: method not GET")
 	}
-	if values := r.Header["Sec-Websocket-Version"]; len(values) == 0 || values[0] != "13" {
+
+	if _, ok := responseHeader["Sec-Websocket-Extensions"]; ok {
+		return u.returnError(w, r, http.StatusInternalServerError, "websocket: application specific Sec-Websocket-Extensions headers are unsupported")
+	}
+
+	if !tokenListContainsValue(r.Header, "Sec-Websocket-Version", "13") {
 		return u.returnError(w, r, http.StatusBadRequest, "websocket: version != 13")
 	}
 
@@ -126,6 +138,18 @@ func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeade
 
 	subprotocol := u.selectSubprotocol(r, responseHeader)
 
+	// Negotiate PMCE
+	var compress bool
+	if u.EnableCompression {
+		for _, ext := range parseExtensions(r.Header) {
+			if ext[""] != "permessage-deflate" {
+				continue
+			}
+			compress = true
+			break
+		}
+	}
+
 	var (
 		netConn net.Conn
 		br      *bufio.Reader
@@ -151,6 +175,11 @@ func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeade
 	c := newConn(netConn, true, u.ReadBufferSize, u.WriteBufferSize)
 	c.subprotocol = subprotocol
 
+	if compress {
+		c.newCompressionWriter = compressNoContextTakeover
+		c.newDecompressionReader = decompressNoContextTakeover
+	}
+
 	p := c.writeBuf[:0]
 	p = append(p, "HTTP/1.1 101 Switching Protocols\r\nUpgrade: websocket\r\nConnection: Upgrade\r\nSec-WebSocket-Accept: "...)
 	p = append(p, computeAcceptKey(challengeKey)...)
@@ -160,6 +189,9 @@ func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeade
 		p = append(p, c.subprotocol...)
 		p = append(p, "\r\n"...)
 	}
+	if compress {
+		p = append(p, "Sec-Websocket-Extensions: permessage-deflate; server_no_context_takeover; client_no_context_takeover\r\n"...)
+	}
 	for k, vs := range responseHeader {
 		if k == "Sec-Websocket-Protocol" {
 			continue
@@ -251,3 +283,10 @@ func Subprotocols(r *http.Request) []string {
 	}
 	return protocols
 }
+
+// IsWebSocketUpgrade returns true if the client requested upgrade to the
+// WebSocket protocol.
+func IsWebSocketUpgrade(r *http.Request) bool {
+	return tokenListContainsValue(r.Header, "Connection", "upgrade") &&
+		tokenListContainsValue(r.Header, "Upgrade", "websocket")
+}

vendor/github.com/gorilla/websocket/util.go

@@ -13,19 +13,6 @@ import (
 	"strings"
 )
 
-// tokenListContainsValue returns true if the 1#token header with the given
-// name contains token.
-func tokenListContainsValue(header http.Header, name string, value string) bool {
-	for _, v := range header[name] {
-		for _, s := range strings.Split(v, ",") {
-			if strings.EqualFold(value, strings.TrimSpace(s)) {
-				return true
-			}
-		}
-	}
-	return false
-}
-
 var keyGUID = []byte("258EAFA5-E914-47DA-95CA-C5AB0DC85B11")
 
 func computeAcceptKey(challengeKey string) string {
@@ -42,3 +29,186 @@ func generateChallengeKey() (string, error) {
 	}
 	return base64.StdEncoding.EncodeToString(p), nil
 }
+
+// Octet types from RFC 2616.
+var octetTypes [256]byte
+
+const (
+	isTokenOctet = 1 << iota
+	isSpaceOctet
+)
+
+func init() {
+	// From RFC 2616
+	//
+	// OCTET      = <any 8-bit sequence of data>
+	// CHAR       = <any US-ASCII character (octets 0 - 127)>
+	// CTL        = <any US-ASCII control character (octets 0 - 31) and DEL (127)>
+	// CR         = <US-ASCII CR, carriage return (13)>
+	// LF         = <US-ASCII LF, linefeed (10)>
+	// SP         = <US-ASCII SP, space (32)>
+	// HT         = <US-ASCII HT, horizontal-tab (9)>
+	// <">        = <US-ASCII double-quote mark (34)>
+	// CRLF       = CR LF
+	// LWS        = [CRLF] 1*( SP | HT )
+	// TEXT       = <any OCTET except CTLs, but including LWS>
+	// separators = "(" | ")" | "<" | ">" | "@" | "," | ";" | ":" | "\" | <">
+	//              | "/" | "[" | "]" | "?" | "=" | "{" | "}" | SP | HT
+	// token      = 1*<any CHAR except CTLs or separators>
+	// qdtext     = <any TEXT except <">>
+
+	for c := 0; c < 256; c++ {
+		var t byte
+		isCtl := c <= 31 || c == 127
+		isChar := 0 <= c && c <= 127
+		isSeparator := strings.IndexRune(" \t\"(),/:;<=>?@[]\\{}", rune(c)) >= 0
+		if strings.IndexRune(" \t\r\n", rune(c)) >= 0 {
+			t |= isSpaceOctet
+		}
+		if isChar && !isCtl && !isSeparator {
+			t |= isTokenOctet
+		}
+		octetTypes[c] = t
+	}
+}
+
+func skipSpace(s string) (rest string) {
+	i := 0
+	for ; i < len(s); i++ {
+		if octetTypes[s[i]]&isSpaceOctet == 0 {
+			break
+		}
+	}
+	return s[i:]
+}
+
+func nextToken(s string) (token, rest string) {
+	i := 0
+	for ; i < len(s); i++ {
+		if octetTypes[s[i]]&isTokenOctet == 0 {
+			break
+		}
+	}
+	return s[:i], s[i:]
+}
+
+func nextTokenOrQuoted(s string) (value string, rest string) {
+	if !strings.HasPrefix(s, "\"") {
+		return nextToken(s)
+	}
+	s = s[1:]
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		case '"':
+			return s[:i], s[i+1:]
+		case '\\':
+			p := make([]byte, len(s)-1)
+			j := copy(p, s[:i])
+			escape := true
+			for i = i + 1; i < len(s); i++ {
+				b := s[i]
+				switch {
+				case escape:
+					escape = false
+					p[j] = b
+					j += 1
+				case b == '\\':
+					escape = true
+				case b == '"':
+					return string(p[:j]), s[i+1:]
+				default:
+					p[j] = b
+					j += 1
+				}
+			}
+			return "", ""
+		}
+	}
+	return "", ""
+}
+
+// tokenListContainsValue returns true if the 1#token header with the given
+// name contains token.
+func tokenListContainsValue(header http.Header, name string, value string) bool {
+headers:
+	for _, s := range header[name] {
+		for {
+			var t string
+			t, s = nextToken(skipSpace(s))
+			if t == "" {
+				continue headers
+			}
+			s = skipSpace(s)
+			if s != "" && s[0] != ',' {
+				continue headers
+			}
+			if strings.EqualFold(t, value) {
+				return true
+			}
+			if s == "" {
+				continue headers
+			}
+			s = s[1:]
+		}
+	}
+	return false
+}
+
+// parseExtensiosn parses WebSocket extensions from a header.
+func parseExtensions(header http.Header) []map[string]string {
+
+	// From RFC 6455:
+	//
+	//  Sec-WebSocket-Extensions = extension-list
+	//  extension-list = 1#extension
+	//  extension = extension-token *( ";" extension-param )
+	//  extension-token = registered-token
+	//  registered-token = token
+	//  extension-param = token [ "=" (token | quoted-string) ]
+	//     ;When using the quoted-string syntax variant, the value
+	//     ;after quoted-string unescaping MUST conform to the
+	//     ;'token' ABNF.
+
+	var result []map[string]string
+headers:
+	for _, s := range header["Sec-Websocket-Extensions"] {
+		for {
+			var t string
+			t, s = nextToken(skipSpace(s))
+			if t == "" {
+				continue headers
+			}
+			ext := map[string]string{"": t}
+			for {
+				s = skipSpace(s)
+				if !strings.HasPrefix(s, ";") {
+					break
+				}
+				var k string
+				k, s = nextToken(skipSpace(s[1:]))
+				if k == "" {
+					continue headers
+				}
+				s = skipSpace(s)
+				var v string
+				if strings.HasPrefix(s, "=") {
+					v, s = nextTokenOrQuoted(skipSpace(s[1:]))
+					s = skipSpace(s)
+				}
+				if s != "" && s[0] != ',' && s[0] != ';' {
+					continue headers
+				}
+				ext[k] = v
+			}
+			if s != "" && s[0] != ',' {
+				continue headers
+			}
+			result = append(result, ext)
+			if s == "" {
+				continue headers
+			}
+			s = s[1:]
+		}
+	}
+	return result
+}

vendor/vendor.json

@@ -314,6 +314,12 @@
 			"version": "v1.21.1",
 			"versionExact": "v1.21.1"
 		},
+		{
+			"checksumSHA1": "B4bk7vdV9aD7AhrtATXfgEacdqE=",
+			"path": "github.com/gorilla/websocket",
+			"revision": "3ab3a8b8831546bd18fd182c20687ca853b2bb13",
+			"revisionTime": "2016-12-15T22:53:35Z"
+		},
 		{
 			"checksumSHA1": "8z32QKTSDusa4QQyunKE4kyYXZ8=",
 			"path": "github.com/patrickmn/go-cache",