websocket: add hybi-13 support

Major changes between hybi-08 and hybi-13
- hybi-08 uses Sec-WebSocket-Origin, but hybi-13 uses Origin
- hybi-13 introduces new close status codes.

hybi-17 spec (editorial changes of hybi-13) mentions
- if a server doesn't support the requested version, it MUST respond
  with Sec-WebSocket-Version headers containing all available versions.
- client MUST close the connection upon receiving a masked frame
- server MUST close the connection upon receiving a non-masked frame
note that hybi-17 still uses "Sec-WebSocket-Version: 13"

see http://code.google.com/p/pywebsocket/wiki/WebSocketProtocolSpec
for changes between spec drafts.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/5147043

src/pkg/websocket/client.go

@@ -26,7 +26,7 @@ func (e *DialError) String() string {
 // NewConfig creates a new WebSocket config for client connection.
 func NewConfig(server, origin string) (config *Config, err os.Error) {
 	config = new(Config)
-	config.Version = ProtocolVersionHybi
+	config.Version = ProtocolVersionHybi13
 	config.Location, err = url.ParseRequest(server)
 	if err != nil {
 		return
@@ -47,7 +47,7 @@ func NewClient(config *Config, rwc io.ReadWriteCloser) (ws *Conn, err os.Error)
 		err = hixie75ClientHandshake(config, br, bw)
 	case ProtocolVersionHixie76, ProtocolVersionHybi00:
 		err = hixie76ClientHandshake(config, br, bw)
-	case ProtocolVersionHybi:
+	case ProtocolVersionHybi08, ProtocolVersionHybi13:
 		err = hybiClientHandshake(config, br, bw)
 	default:
 		err = ErrBadProtocolVersion
@@ -59,7 +59,7 @@ func NewClient(config *Config, rwc io.ReadWriteCloser) (ws *Conn, err os.Error)
 	switch config.Version {
 	case ProtocolVersionHixie75, ProtocolVersionHixie76, ProtocolVersionHybi00:
 		ws = newHixieClientConn(config, buf, rwc)
-	case ProtocolVersionHybi:
+	case ProtocolVersionHybi08, ProtocolVersionHybi13:
 		ws = newHybiClientConn(config, buf, rwc)
 	}
 	return

src/pkg/websocket/hybi.go

@@ -5,7 +5,7 @@
 package websocket
 
 // This file implements a protocol of hybi draft.
-// http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-10
+// http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-17
 
 import (
 	"bufio"
@@ -33,6 +33,10 @@ const (
 	closeStatusFrameTooLarge     = 1004
 	closeStatusNoStatusRcvd      = 1005
 	closeStatusAbnormalClosure   = 1006
+	closeStatusBadMessageData    = 1007
+	closeStatusPolicyViolation   = 1008
+	closeStatusTooBigData        = 1009
+	closeStatusExtensionMismatch = 1010
 
 	maxControlFramePayloadLength = 125
 )
@@ -101,8 +105,8 @@ type hybiFrameReaderFactory struct {
 }
 
 // NewFrameReader reads a frame header from the connection, and creates new reader for the frame.
-// See Section 4.2 Base Frameing protocol for detail.
+// See Section 5.2 Base Frameing protocol for detail.
-// http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-10#section-4.2
+// http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-17#section-5.2
 func (buf hybiFrameReaderFactory) NewFrameReader() (frame frameReader, err os.Error) {
 	hybiFrame := new(hybiFrameReader)
 	frame = hybiFrame
@@ -258,6 +262,12 @@ func (handler *hybiFrameHandler) HandleFrame(frame frameReader) (r frameReader,
 			handler.WriteClose(closeStatusProtocolError)
 			return nil, os.EOF
 		}
+	} else {
+		// The server MUST NOT mask all frames.
+		if frame.(*hybiFrameReader).header.MaskingKey != nil {
+			handler.WriteClose(closeStatusProtocolError)
+			return nil, os.EOF
+		}
 	}
 	if header := frame.HeaderReader(); header != nil {
 		io.Copy(ioutil.Discard, header)
@@ -366,9 +376,18 @@ func getNonceAccept(nonce []byte) (expected []byte, err os.Error) {
 	return
 }
 
-// Client handhake described in draft-ietf-hybi-thewebsocket-protocol-09
+func isHybiVersion(version int) bool {
+	switch version {
+	case ProtocolVersionHybi08, ProtocolVersionHybi13:
+		return true
+	default:
+	}
+	return false
+}
+
+// Client handhake described in draft-ietf-hybi-thewebsocket-protocol-17
 func hybiClientHandshake(config *Config, br *bufio.Reader, bw *bufio.Writer) (err os.Error) {
-	if config.Version != ProtocolVersionHybi {
+	if !isHybiVersion(config.Version) {
 		panic("wrong protocol version.")
 	}
 
@@ -382,7 +401,11 @@ func hybiClientHandshake(config *Config, br *bufio.Reader, bw *bufio.Writer) (er
 		nonce = []byte(config.handshakeData["key"])
 	}
 	bw.WriteString("Sec-WebSocket-Key: " + string(nonce) + "\r\n")
+	if config.Version == ProtocolVersionHybi13 {
+		bw.WriteString("Origin: " + strings.ToLower(config.Origin.String()) + "\r\n")
+	} else if config.Version == ProtocolVersionHybi08 {
 		bw.WriteString("Sec-WebSocket-Origin: " + strings.ToLower(config.Origin.String()) + "\r\n")
+	}
 	bw.WriteString("Sec-WebSocket-Version: " + fmt.Sprintf("%d", config.Version) + "\r\n")
 	if len(config.Protocol) > 0 {
 		bw.WriteString("Sec-WebSocket-Protocol: " + strings.Join(config.Protocol, ", ") + "\r\n")
@@ -446,7 +469,7 @@ type hybiServerHandshaker struct {
 }
 
 func (c *hybiServerHandshaker) ReadHandshake(buf *bufio.Reader, req *http.Request) (code int, err os.Error) {
-	c.Version = ProtocolVersionHybi
+	c.Version = ProtocolVersionHybi13
 	if req.Method != "GET" {
 		return http.StatusMethodNotAllowed, ErrBadRequestMethod
 	}
@@ -462,12 +485,20 @@ func (c *hybiServerHandshaker) ReadHandshake(buf *bufio.Reader, req *http.Reques
 		return http.StatusBadRequest, ErrChallengeResponse
 	}
 	version := req.Header.Get("Sec-Websocket-Version")
-	if version != fmt.Sprintf("%d", c.Version) {
+	var origin string
+	switch version {
+	case "13":
+		c.Version = ProtocolVersionHybi13
+		origin = req.Header.Get("Origin")
+	case "8":
+		c.Version = ProtocolVersionHybi08
+		origin = req.Header.Get("Sec-Websocket-Origin")
+	default:
 		return http.StatusBadRequest, ErrBadWebSocketVersion
 	}
-	c.Origin, err = url.ParseRequest(req.Header.Get("Sec-Websocket-Origin"))
+	c.Origin, err = url.ParseRequest(origin)
 	if err != nil {
-		return http.StatusBadRequest, err
+		return http.StatusForbidden, err
 	}
 	var scheme string
 	if req.TLS != nil {

src/pkg/websocket/hybi_test.go

@@ -16,7 +16,7 @@ import (
 )
 
 // Test the getNonceAccept function with values in
-// http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-09
+// http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-17
 func TestSecWebSocketAccept(t *testing.T) {
 	nonce := []byte("dGhlIHNhbXBsZSBub25jZQ==")
 	expected := []byte("s3pPLMBiTxaQ9kYGzzhZRbK+xOo=")
@@ -52,7 +52,69 @@ Sec-WebSocket-Protocol: chat
 	}
 	config.Protocol = append(config.Protocol, "chat")
 	config.Protocol = append(config.Protocol, "superchat")
-	config.Version = ProtocolVersionHybi
+	config.Version = ProtocolVersionHybi13
+
+	config.handshakeData = map[string]string{
+		"key": "dGhlIHNhbXBsZSBub25jZQ==",
+	}
+	err = hybiClientHandshake(config, br, bw)
+	if err != nil {
+		t.Errorf("handshake failed: %v", err)
+	}
+	req, err := http.ReadRequest(bufio.NewReader(b))
+	if err != nil {
+		t.Errorf("read request: %v", err)
+	}
+	if req.Method != "GET" {
+		t.Errorf("request method expected GET, but got %q", req.Method)
+	}
+	if req.RawURL != "/chat" {
+		t.Errorf("request path expected /chat, but got %q", req.RawURL)
+	}
+	if req.Proto != "HTTP/1.1" {
+		t.Errorf("request proto expected HTTP/1.1, but got %q", req.Proto)
+	}
+	if req.Host != "server.example.com" {
+		t.Errorf("request Host expected server.example.com, but got %v", req.Host)
+	}
+	var expectedHeader = map[string]string{
+		"Connection":             "Upgrade",
+		"Upgrade":                "websocket",
+		"Sec-Websocket-Key":      config.handshakeData["key"],
+		"Origin":                 config.Origin.String(),
+		"Sec-Websocket-Protocol": "chat, superchat",
+		"Sec-Websocket-Version":  fmt.Sprintf("%d", ProtocolVersionHybi13),
+	}
+	for k, v := range expectedHeader {
+		if req.Header.Get(k) != v {
+			t.Errorf(fmt.Sprintf("%s expected %q but got %q", k, v, req.Header.Get(k)))
+		}
+	}
+}
+
+func TestHybiClientHandshakeHybi08(t *testing.T) {
+	b := bytes.NewBuffer([]byte{})
+	bw := bufio.NewWriter(b)
+	br := bufio.NewReader(strings.NewReader(`HTTP/1.1 101 Switching Protocols
+Upgrade: websocket
+Connection: Upgrade
+Sec-WebSocket-Accept: s3pPLMBiTxaQ9kYGzzhZRbK+xOo=
+Sec-WebSocket-Protocol: chat
+
+`))
+	var err os.Error
+	config := new(Config)
+	config.Location, err = url.ParseRequest("ws://server.example.com/chat")
+	if err != nil {
+		t.Fatal("location url", err)
+	}
+	config.Origin, err = url.ParseRequest("http://example.com")
+	if err != nil {
+		t.Fatal("origin url", err)
+	}
+	config.Protocol = append(config.Protocol, "chat")
+	config.Protocol = append(config.Protocol, "superchat")
+	config.Version = ProtocolVersionHybi08
 
 	config.handshakeData = map[string]string{
 		"key": "dGhlIHNhbXBsZSBub25jZQ==",
@@ -83,7 +145,7 @@ Sec-WebSocket-Protocol: chat
 		"Sec-Websocket-Key":      config.handshakeData["key"],
 		"Sec-Websocket-Origin":   config.Origin.String(),
 		"Sec-Websocket-Protocol": "chat, superchat",
-		"Sec-Websocket-Version":  fmt.Sprintf("%d", ProtocolVersionHybi),
+		"Sec-Websocket-Version":  fmt.Sprintf("%d", ProtocolVersionHybi08),
 	}
 	for k, v := range expectedHeader {
 		if req.Header.Get(k) != v {
@@ -100,6 +162,52 @@ Host: server.example.com
 Upgrade: websocket
 Connection: Upgrade
 Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
+Origin: http://example.com
+Sec-WebSocket-Protocol: chat, superchat
+Sec-WebSocket-Version: 13
+
+`))
+	req, err := http.ReadRequest(br)
+	if err != nil {
+		t.Fatal("request", err)
+	}
+	code, err := handshaker.ReadHandshake(br, req)
+	if err != nil {
+		t.Errorf("handshake failed: %v", err)
+	}
+	if code != http.StatusSwitchingProtocols {
+		t.Errorf("status expected %q but got %q", http.StatusSwitchingProtocols, code)
+	}
+	b := bytes.NewBuffer([]byte{})
+	bw := bufio.NewWriter(b)
+
+	config.Protocol = []string{"chat"}
+
+	err = handshaker.AcceptHandshake(bw)
+	if err != nil {
+		t.Errorf("handshake response failed: %v", err)
+	}
+	expectedResponse := strings.Join([]string{
+		"HTTP/1.1 101 Switching Protocols",
+		"Upgrade: websocket",
+		"Connection: Upgrade",
+		"Sec-WebSocket-Accept: s3pPLMBiTxaQ9kYGzzhZRbK+xOo=",
+		"Sec-WebSocket-Protocol: chat",
+		"", ""}, "\r\n")
+
+	if b.String() != expectedResponse {
+		t.Errorf("handshake expected %q but got %q", expectedResponse, b.String())
+	}
+}
+
+func TestHybiServerHandshakeHybi08(t *testing.T) {
+	config := new(Config)
+	handshaker := &hybiServerHandshaker{Config: config}
+	br := bufio.NewReader(strings.NewReader(`GET /chat HTTP/1.1
+Host: server.example.com
+Upgrade: websocket
+Connection: Upgrade
+Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
 Sec-WebSocket-Origin: http://example.com
 Sec-WebSocket-Protocol: chat, superchat
 Sec-WebSocket-Version: 8
@@ -138,6 +246,32 @@ Sec-WebSocket-Version: 8
 	}
 }
 
+func TestHybiServerHandshakeHybiBadVersion(t *testing.T) {
+	config := new(Config)
+	handshaker := &hybiServerHandshaker{Config: config}
+	br := bufio.NewReader(strings.NewReader(`GET /chat HTTP/1.1
+Host: server.example.com
+Upgrade: websocket
+Connection: Upgrade
+Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
+Sec-WebSocket-Origin: http://example.com
+Sec-WebSocket-Protocol: chat, superchat
+Sec-WebSocket-Version: 9
+
+`))
+	req, err := http.ReadRequest(br)
+	if err != nil {
+		t.Fatal("request", err)
+	}
+	code, err := handshaker.ReadHandshake(br, req)
+	if err != ErrBadWebSocketVersion {
+		t.Errorf("handshake expected err %q but got %q", ErrBadWebSocketVersion, err)
+	}
+	if code != http.StatusBadRequest {
+		t.Errorf("status expected %q but got %q", http.StatusBadRequest, code)
+	}
+}
+
 func testHybiFrame(t *testing.T, testHeader, testPayload, testMaskedPayload []byte, frameHeader *hybiFrameHeader) {
 	b := bytes.NewBuffer([]byte{})
 	frameWriterFactory := &hybiFrameWriterFactory{bufio.NewWriter(b), false}
@@ -247,7 +381,7 @@ func TestHybiLongFrame(t *testing.T) {
 	testHybiFrame(t, []byte{0x81, 127, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00}, payload, payload, frameHeader)
 }
 
-func TestHybiRead(t *testing.T) {
+func TestHybiClientRead(t *testing.T) {
 	wireData := []byte{0x81, 0x05, 'h', 'e', 'l', 'l', 'o',
 		0x89, 0x05, 'h', 'e', 'l', 'l', 'o', // ping
 		0x81, 0x05, 'w', 'o', 'r', 'l', 'd'}
@@ -325,16 +459,17 @@ func TestHybiShortRead(t *testing.T) {
 	}
 }
 
-func TestHybiReadWithMasking(t *testing.T) {
+func TestHybiServerRead(t *testing.T) {
 	wireData := []byte{0x81, 0x85, 0xcc, 0x55, 0x80, 0x20,
 		0xa4, 0x30, 0xec, 0x4c, 0xa3, // hello
-		0x89, 0x05, 'h', 'e', 'l', 'l', 'o',
+		0x89, 0x85, 0xcc, 0x55, 0x80, 0x20,
+		0xa4, 0x30, 0xec, 0x4c, 0xa3, // ping: hello
 		0x81, 0x85, 0xed, 0x83, 0xb4, 0x24,
 		0x9a, 0xec, 0xc6, 0x48, 0x89, // world
 	}
 	br := bufio.NewReader(bytes.NewBuffer(wireData))
 	bw := bufio.NewWriter(bytes.NewBuffer([]byte{}))
-	conn := newHybiConn(newConfig(t, "/"), bufio.NewReadWriter(br, bw), nil, nil)
+	conn := newHybiConn(newConfig(t, "/"), bufio.NewReadWriter(br, bw), nil, new(http.Request))
 
 	expected := [][]byte{[]byte("hello"), []byte("world")}
 
@@ -369,3 +504,32 @@ func TestHybiReadWithMasking(t *testing.T) {
 		t.Errorf("expect read 0, got %d", n)
 	}
 }
+
+func TestHybiServerReadWithoutMasking(t *testing.T) {
+	wireData := []byte{0x81, 0x05, 'h', 'e', 'l', 'l', 'o'}
+	br := bufio.NewReader(bytes.NewBuffer(wireData))
+	bw := bufio.NewWriter(bytes.NewBuffer([]byte{}))
+	conn := newHybiConn(newConfig(t, "/"), bufio.NewReadWriter(br, bw), nil, new(http.Request))
+	// server MUST close the connection upon receiving a non-masked frame.
+	msg := make([]byte, 512)
+	_, err := conn.Read(msg)
+	if err != os.EOF {
+		t.Errorf("read 1st frame, expect %q, but got %q", os.EOF, err)
+	}
+}
+
+func TestHybiClientReadWithMasking(t *testing.T) {
+	wireData := []byte{0x81, 0x85, 0xcc, 0x55, 0x80, 0x20,
+		0xa4, 0x30, 0xec, 0x4c, 0xa3, // hello
+	}
+	br := bufio.NewReader(bytes.NewBuffer(wireData))
+	bw := bufio.NewWriter(bytes.NewBuffer([]byte{}))
+	conn := newHybiConn(newConfig(t, "/"), bufio.NewReadWriter(br, bw), nil, nil)
+
+	// client MUST close the connection upon receiving a masked frame.
+	msg := make([]byte, 512)
+	_, err := conn.Read(msg)
+	if err != os.EOF {
+		t.Errorf("read 1st frame, expect %q, but got %q", os.EOF, err)
+	}
+}

src/pkg/websocket/server.go

@@ -16,6 +16,13 @@ func newServerConn(rwc io.ReadWriteCloser, buf *bufio.ReadWriter, req *http.Requ
 	config := new(Config)
 	var hs serverHandshaker = &hybiServerHandshaker{Config: config}
 	code, err := hs.ReadHandshake(buf.Reader, req)
+	if err == ErrBadWebSocketVersion {
+		fmt.Fprintf(buf, "HTTP/1.1 %03d %s\r\n", code, http.StatusText(code))
+		fmt.Fprintf(buf, "Sec-WebSocket-Version: %s\r\n", SupportedProtocolVersion)
+		buf.WriteString("\r\n")
+		buf.WriteString(err.String())
+		return
+	}
 	if err != nil {
 		hs = &hixie76ServerHandshaker{Config: config}
 		code, err = hs.ReadHandshake(buf.Reader, req)

src/pkg/websocket/websocket.go

@@ -23,7 +23,10 @@ const (
 	ProtocolVersionHixie75   = -75
 	ProtocolVersionHixie76   = -76
 	ProtocolVersionHybi00    = 0
-	ProtocolVersionHybi    = 8
+	ProtocolVersionHybi08    = 8
+	ProtocolVersionHybi13    = 13
+	ProtocolVersionHybi      = ProtocolVersionHybi13
+	SupportedProtocolVersion = "13, 8"
 
 	ContinuationFrame = 0
 	TextFrame         = 1
@@ -39,23 +42,23 @@ type ProtocolError struct {
 	ErrorString string
 }
 
-func (err ProtocolError) String() string { return err.ErrorString }
+func (err *ProtocolError) String() string { return err.ErrorString }
 
 var (
-	ErrBadProtocolVersion   = ProtocolError{"bad protocol version"}
+	ErrBadProtocolVersion   = &ProtocolError{"bad protocol version"}
-	ErrBadScheme            = ProtocolError{"bad scheme"}
+	ErrBadScheme            = &ProtocolError{"bad scheme"}
-	ErrBadStatus            = ProtocolError{"bad status"}
+	ErrBadStatus            = &ProtocolError{"bad status"}
-	ErrBadUpgrade           = ProtocolError{"missing or bad upgrade"}
+	ErrBadUpgrade           = &ProtocolError{"missing or bad upgrade"}
-	ErrBadWebSocketOrigin   = ProtocolError{"missing or bad WebSocket-Origin"}
+	ErrBadWebSocketOrigin   = &ProtocolError{"missing or bad WebSocket-Origin"}
-	ErrBadWebSocketLocation = ProtocolError{"missing or bad WebSocket-Location"}
+	ErrBadWebSocketLocation = &ProtocolError{"missing or bad WebSocket-Location"}
-	ErrBadWebSocketProtocol = ProtocolError{"missing or bad WebSocket-Protocol"}
+	ErrBadWebSocketProtocol = &ProtocolError{"missing or bad WebSocket-Protocol"}
-	ErrBadWebSocketVersion  = ProtocolError{"missing or bad WebSocket Version"}
+	ErrBadWebSocketVersion  = &ProtocolError{"missing or bad WebSocket Version"}
-	ErrChallengeResponse    = ProtocolError{"mismatch challenge/response"}
+	ErrChallengeResponse    = &ProtocolError{"mismatch challenge/response"}
-	ErrBadFrame             = ProtocolError{"bad frame"}
+	ErrBadFrame             = &ProtocolError{"bad frame"}
-	ErrBadFrameBoundary     = ProtocolError{"not on frame boundary"}
+	ErrBadFrameBoundary     = &ProtocolError{"not on frame boundary"}
-	ErrNotWebSocket         = ProtocolError{"not websocket protocol"}
+	ErrNotWebSocket         = &ProtocolError{"not websocket protocol"}
-	ErrBadRequestMethod     = ProtocolError{"bad method"}
+	ErrBadRequestMethod     = &ProtocolError{"bad method"}
-	ErrNotSupported         = ProtocolError{"not supported"}
+	ErrNotSupported         = &ProtocolError{"not supported"}
 )
 
 // Addr is an implementation of net.Addr for WebSocket.