rpc: implement websockets with github.com/gorilla/websocket (#19866)

* rpc: implement websockets with github.com/gorilla/websocket

This change makes package rpc use the github.com/gorilla/websocket
package for WebSockets instead of golang.org/x/net/websocket. The new
library is more robust and supports all WebSocket features including
continuation frames.

There are new tests for two issues with the previously-used library:

  - TestWebsocketClientPing checks handling of Ping frames.
  - TestWebsocketLargeCall checks whether the request size limit is
    applied correctly.

* rpc: raise HTTP/WebSocket request size limit to 5MB

* rpc: remove default origin for client connections

The client used to put the local hostname into the Origin header because
the server wanted an origin to accept the connection, but that's silly:
Origin is for browsers/websites. The nobody would whitelist a particular
hostname.

Now that the server doesn't need Origin anymore, don't bother setting
one for clients. Users who need an origin can use DialWebsocket to
create a client with arbitrary origin if needed.

* vendor: put golang.org/x/net/websocket back

* rpc: don't set Origin header for empty (default) origin

* rpc: add HTTP status code to handshake error

This makes it easier to debug failing connections.

* ethstats: use github.com/gorilla/websocket

* rpc: fix lint

ethstats/ethstats.go

@@ -23,7 +23,7 @@ import (
 	"errors"
 	"fmt"
 	"math/big"
-	"net"
+	"net/http"
 	"regexp"
 	"runtime"
 	"strconv"
@@ -41,7 +41,7 @@ import (
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/p2p"
 	"github.com/ethereum/go-ethereum/rpc"
-	"golang.org/x/net/websocket"
+	"github.com/gorilla/websocket"
 )
 
 const (
@@ -200,21 +200,21 @@ func (s *Service) loop() {
 		path := fmt.Sprintf("%s/api", s.host)
 		urls := []string{path}
 
-		if !strings.Contains(path, "://") { // url.Parse and url.IsAbs is unsuitable (https://github.com/golang/go/issues/19779)
+		// url.Parse and url.IsAbs is unsuitable (https://github.com/golang/go/issues/19779)
+		if !strings.Contains(path, "://") {
 			urls = []string{"wss://" + path, "ws://" + path}
 		}
 		// Establish a websocket connection to the server on any supported URL
 		var (
-			conf *websocket.Config
 			conn *websocket.Conn
 			err  error
 		)
+		dialer := websocket.Dialer{HandshakeTimeout: 5 * time.Second}
+		header := make(http.Header)
+		header.Set("origin", "http://localhost")
 		for _, url := range urls {
-			if conf, err = websocket.NewConfig(url, "http://localhost/"); err != nil {
+			conn, _, err = dialer.Dial(url, header)
-				continue
+			if err == nil {
-			}
-			conf.Dialer = &net.Dialer{Timeout: 5 * time.Second}
-			if conn, err = websocket.DialConfig(conf); err == nil {
 				break
 			}
 		}
@@ -284,7 +284,7 @@ func (s *Service) readLoop(conn *websocket.Conn) {
 	for {
 		// Retrieve the next generic network packet and bail out on error
 		var msg map[string][]interface{}
-		if err := websocket.JSON.Receive(conn, &msg); err != nil {
+		if err := conn.ReadJSON(&msg); err != nil {
 			log.Warn("Failed to decode stats server message", "err", err)
 			return
 		}
@@ -399,12 +399,12 @@ func (s *Service) login(conn *websocket.Conn) error {
 	login := map[string][]interface{}{
 		"emit": {"hello", auth},
 	}
-	if err := websocket.JSON.Send(conn, login); err != nil {
+	if err := conn.WriteJSON(login); err != nil {
 		return err
 	}
 	// Retrieve the remote ack or connection termination
 	var ack map[string][]string
-	if err := websocket.JSON.Receive(conn, &ack); err != nil || len(ack["emit"]) != 1 || ack["emit"][0] != "ready" {
+	if err := conn.ReadJSON(&ack); err != nil || len(ack["emit"]) != 1 || ack["emit"][0] != "ready" {
 		return errors.New("unauthorized")
 	}
 	return nil
@@ -441,7 +441,7 @@ func (s *Service) reportLatency(conn *websocket.Conn) error {
 			"clientTime": start.String(),
 		}},
 	}
-	if err := websocket.JSON.Send(conn, ping); err != nil {
+	if err := conn.WriteJSON(ping); err != nil {
 		return err
 	}
 	// Wait for the pong request to arrive back
@@ -463,7 +463,7 @@ func (s *Service) reportLatency(conn *websocket.Conn) error {
 			"latency": latency,
 		}},
 	}
-	return websocket.JSON.Send(conn, stats)
+	return conn.WriteJSON(stats)
 }
 
 // blockStats is the information to report about individual blocks.
@@ -514,7 +514,7 @@ func (s *Service) reportBlock(conn *websocket.Conn, block *types.Block) error {
 	report := map[string][]interface{}{
 		"emit": {"block", stats},
 	}
-	return websocket.JSON.Send(conn, report)
+	return conn.WriteJSON(report)
 }
 
 // assembleBlockStats retrieves any required metadata to report a single block
@@ -628,7 +628,7 @@ func (s *Service) reportHistory(conn *websocket.Conn, list []uint64) error {
 	report := map[string][]interface{}{
 		"emit": {"history", stats},
 	}
-	return websocket.JSON.Send(conn, report)
+	return conn.WriteJSON(report)
 }
 
 // pendStats is the information to report about pending transactions.
@@ -658,7 +658,7 @@ func (s *Service) reportPending(conn *websocket.Conn) error {
 	report := map[string][]interface{}{
 		"emit": {"pending", stats},
 	}
-	return websocket.JSON.Send(conn, report)
+	return conn.WriteJSON(report)
 }
 
 // nodeStats is the information to report about the local node.
@@ -713,5 +713,5 @@ func (s *Service) reportStats(conn *websocket.Conn) error {
 	report := map[string][]interface{}{
 		"emit": {"stats", stats},
 	}
-	return websocket.JSON.Send(conn, report)
+	return conn.WriteJSON(report)
 }

rpc/client.go

@@ -41,7 +41,6 @@ var (
 
 const (
 	// Timeouts
-	tcpKeepAliveInterval = 30 * time.Second
 	defaultDialTimeout = 10 * time.Second // used if context has no deadline
 	subscribeTimeout   = 5 * time.Second  // overall timeout eth_subscribe, rpc_modules calls
 )

rpc/http.go

@@ -36,7 +36,7 @@ import (
 )
 
 const (
-	maxRequestContentLength = 1024 * 512
+	maxRequestContentLength = 1024 * 1024 * 5
 	contentType             = "application/json"
 )
 

rpc/ipc_unix.go

@@ -50,5 +50,5 @@ func ipcListen(endpoint string) (net.Listener, error) {
 
 // newIPCConnection will connect to a Unix socket on the given endpoint.
 func newIPCConnection(ctx context.Context, endpoint string) (net.Conn, error) {
-	return dialContext(ctx, "unix", endpoint)
+	return new(net.Dialer).DialContext(ctx, "unix", endpoint)
 }

rpc/json.go

@@ -141,6 +141,11 @@ type Conn interface {
 	SetWriteDeadline(time.Time) error
 }
 
+type deadlineCloser interface {
+	io.Closer
+	SetWriteDeadline(time.Time) error
+}
+
 // ConnRemoteAddr wraps the RemoteAddr operation, which returns a description
 // of the peer address of a connection. If a Conn also implements ConnRemoteAddr, this
 // description is used in log messages.
@@ -165,12 +170,10 @@ type jsonCodec struct {
 	decode     func(v interface{}) error // decoder to allow multiple transports
 	encMu      sync.Mutex                // guards the encoder
 	encode     func(v interface{}) error // encoder to allow multiple transports
-	conn       Conn
+	conn       deadlineCloser
 }
 
-// NewCodec creates a new RPC server codec with support for JSON-RPC 2.0 based
+func newCodec(conn deadlineCloser, encode, decode func(v interface{}) error) ServerCodec {
-// on explicitly given encoding and decoding methods.
-func NewCodec(conn Conn, encode, decode func(v interface{}) error) ServerCodec {
 	codec := &jsonCodec{
 		closed: make(chan interface{}),
 		encode: encode,
@@ -183,12 +186,14 @@ func NewCodec(conn Conn, encode, decode func(v interface{}) error) ServerCodec {
 	return codec
 }
 
-// NewJSONCodec creates a new RPC server codec with support for JSON-RPC 2.0.
+// NewJSONCodec creates a codec that reads from the given connection. If conn implements
+// ConnRemoteAddr, log messages will use it to include the remote address of the
+// connection.
 func NewJSONCodec(conn Conn) ServerCodec {
 	enc := json.NewEncoder(conn)
 	dec := json.NewDecoder(conn)
 	dec.UseNumber()
-	return NewCodec(conn, enc.Encode, dec.Decode)
+	return newCodec(conn, enc.Encode, dec.Decode)
 }
 
 func (c *jsonCodec) RemoteAddr() string {

rpc/websocket.go

@@ -17,78 +17,26 @@
 package rpc
 
 import (
-	"bytes"
 	"context"
-	"crypto/tls"
 	"encoding/base64"
-	"encoding/json"
-	"errors"
 	"fmt"
-	"net"
 	"net/http"
 	"net/url"
 	"os"
 	"strings"
-	"time"
+	"sync"
 
 	mapset "github.com/deckarep/golang-set"
 	"github.com/ethereum/go-ethereum/log"
-	"golang.org/x/net/websocket"
+	"github.com/gorilla/websocket"
 )
 
-// websocketJSONCodec is a custom JSON codec with payload size enforcement and
+const (
-// special number parsing.
+	wsReadBuffer  = 1024
-var websocketJSONCodec = websocket.Codec{
+	wsWriteBuffer = 1024
-	// Marshal is the stock JSON marshaller used by the websocket library too.
+)
-	Marshal: func(v interface{}) ([]byte, byte, error) {
-		msg, err := json.Marshal(v)
-		return msg, websocket.TextFrame, err
-	},
-	// Unmarshal is a specialized unmarshaller to properly convert numbers.
-	Unmarshal: func(msg []byte, payloadType byte, v interface{}) error {
-		dec := json.NewDecoder(bytes.NewReader(msg))
-		dec.UseNumber()
 
-		return dec.Decode(v)
+var wsBufferPool = new(sync.Pool)
-	},
-}
-
-// WebsocketHandler returns a handler that serves JSON-RPC to WebSocket connections.
-//
-// allowedOrigins should be a comma-separated list of allowed origin URLs.
-// To allow connections with any origin, pass "*".
-func (s *Server) WebsocketHandler(allowedOrigins []string) http.Handler {
-	return websocket.Server{
-		Handshake: wsHandshakeValidator(allowedOrigins),
-		Handler: func(conn *websocket.Conn) {
-			codec := newWebsocketCodec(conn)
-			s.ServeCodec(codec, OptionMethodInvocation|OptionSubscriptions)
-		},
-	}
-}
-
-func newWebsocketCodec(conn *websocket.Conn) ServerCodec {
-	// Create a custom encode/decode pair to enforce payload size and number encoding
-	conn.MaxPayloadBytes = maxRequestContentLength
-	encoder := func(v interface{}) error {
-		return websocketJSONCodec.Send(conn, v)
-	}
-	decoder := func(v interface{}) error {
-		return websocketJSONCodec.Receive(conn, v)
-	}
-	rpcconn := Conn(conn)
-	if conn.IsServerConn() {
-		// Override remote address with the actual socket address because
-		// package websocket crashes if there is no request origin.
-		addr := conn.Request().RemoteAddr
-		if wsaddr := conn.RemoteAddr().(*websocket.Addr); wsaddr.URL != nil {
-			// Add origin if present.
-			addr += "(" + wsaddr.URL.String() + ")"
-		}
-		rpcconn = connWithRemoteAddr{conn, addr}
-	}
-	return NewCodec(rpcconn, encoder, decoder)
-}
 
 // NewWSServer creates a new websocket RPC server around an API provider.
 //
@@ -97,10 +45,32 @@ func NewWSServer(allowedOrigins []string, srv *Server) *http.Server {
 	return &http.Server{Handler: srv.WebsocketHandler(allowedOrigins)}
 }
 
+// WebsocketHandler returns a handler that serves JSON-RPC to WebSocket connections.
+//
+// allowedOrigins should be a comma-separated list of allowed origin URLs.
+// To allow connections with any origin, pass "*".
+func (s *Server) WebsocketHandler(allowedOrigins []string) http.Handler {
+	var upgrader = websocket.Upgrader{
+		ReadBufferSize:  wsReadBuffer,
+		WriteBufferSize: wsWriteBuffer,
+		WriteBufferPool: wsBufferPool,
+		CheckOrigin:     wsHandshakeValidator(allowedOrigins),
+	}
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		conn, err := upgrader.Upgrade(w, r, nil)
+		if err != nil {
+			log.Debug("WebSocket upgrade failed", "err", err)
+			return
+		}
+		codec := newWebsocketCodec(conn)
+		s.ServeCodec(codec, OptionMethodInvocation|OptionSubscriptions)
+	})
+}
+
 // wsHandshakeValidator returns a handler that verifies the origin during the
 // websocket upgrade process. When a '*' is specified as an allowed origins all
 // connections are accepted.
-func wsHandshakeValidator(allowedOrigins []string) func(*websocket.Config, *http.Request) error {
+func wsHandshakeValidator(allowedOrigins []string) func(*http.Request) bool {
 	origins := mapset.NewSet()
 	allowAllOrigins := false
 
@@ -112,7 +82,6 @@ func wsHandshakeValidator(allowedOrigins []string) func(*websocket.Config, *http
 			origins.Add(strings.ToLower(origin))
 		}
 	}
-
 	// allow localhost if no allowedOrigins are specified.
 	if len(origins.ToSlice()) == 0 {
 		origins.Add("http://localhost")
@@ -120,52 +89,39 @@ func wsHandshakeValidator(allowedOrigins []string) func(*websocket.Config, *http
 			origins.Add("http://" + strings.ToLower(hostname))
 		}
 	}
-
 	log.Debug(fmt.Sprintf("Allowed origin(s) for WS RPC interface %v", origins.ToSlice()))
 
-	f := func(cfg *websocket.Config, req *http.Request) error {
+	f := func(req *http.Request) bool {
 		// Skip origin verification if no Origin header is present. The origin check
 		// is supposed to protect against browser based attacks. Browsers always set
 		// Origin. Non-browser software can put anything in origin and checking it doesn't
 		// provide additional security.
 		if _, ok := req.Header["Origin"]; !ok {
-			return nil
+			return true
 		}
 		// Verify origin against whitelist.
 		origin := strings.ToLower(req.Header.Get("Origin"))
 		if allowAllOrigins || origins.Contains(origin) {
-			return nil
+			return true
 		}
 		log.Warn("Rejected WebSocket connection", "origin", origin)
-		return errors.New("origin not allowed")
+		return false
 	}
 
 	return f
 }
 
-func wsGetConfig(endpoint, origin string) (*websocket.Config, error) {
+type wsHandshakeError struct {
-	if origin == "" {
+	err    error
-		var err error
+	status string
-		if origin, err = os.Hostname(); err != nil {
+}
-			return nil, err
-		}
-		if strings.HasPrefix(endpoint, "wss") {
-			origin = "https://" + strings.ToLower(origin)
-		} else {
-			origin = "http://" + strings.ToLower(origin)
-		}
-	}
-	config, err := websocket.NewConfig(endpoint, origin)
-	if err != nil {
-		return nil, err
-	}
 
-	if config.Location.User != nil {
+func (e wsHandshakeError) Error() string {
-		b64auth := base64.StdEncoding.EncodeToString([]byte(config.Location.User.String()))
+	s := e.err.Error()
-		config.Header.Add("Authorization", "Basic "+b64auth)
+	if e.status != "" {
-		config.Location.User = nil
+		s += " (HTTP status " + e.status + ")"
 	}
-	return config, nil
+	return s
 }
 
 // DialWebsocket creates a new RPC client that communicates with a JSON-RPC server
@@ -174,65 +130,46 @@ func wsGetConfig(endpoint, origin string) (*websocket.Config, error) {
 // The context is used for the initial connection establishment. It does not
 // affect subsequent interactions with the client.
 func DialWebsocket(ctx context.Context, endpoint, origin string) (*Client, error) {
-	config, err := wsGetConfig(endpoint, origin)
+	endpoint, header, err := wsClientHeaders(endpoint, origin)
 	if err != nil {
 		return nil, err
 	}
-
+	dialer := websocket.Dialer{
+		ReadBufferSize:  wsReadBuffer,
+		WriteBufferSize: wsWriteBuffer,
+		WriteBufferPool: wsBufferPool,
+	}
 	return newClient(ctx, func(ctx context.Context) (ServerCodec, error) {
-		conn, err := wsDialContext(ctx, config)
+		conn, resp, err := dialer.DialContext(ctx, endpoint, header)
 		if err != nil {
-			return nil, err
+			hErr := wsHandshakeError{err: err}
+			if resp != nil {
+				hErr.status = resp.Status
+			}
+			return nil, hErr
 		}
 		return newWebsocketCodec(conn), nil
 	})
 }
 
-func wsDialContext(ctx context.Context, config *websocket.Config) (*websocket.Conn, error) {
+func wsClientHeaders(endpoint, origin string) (string, http.Header, error) {
-	var conn net.Conn
+	endpointURL, err := url.Parse(endpoint)
-	var err error
-	switch config.Location.Scheme {
-	case "ws":
-		conn, err = dialContext(ctx, "tcp", wsDialAddress(config.Location))
-	case "wss":
-		dialer := contextDialer(ctx)
-		conn, err = tls.DialWithDialer(dialer, "tcp", wsDialAddress(config.Location), config.TlsConfig)
-	default:
-		err = websocket.ErrBadScheme
-	}
 	if err != nil {
-		return nil, err
+		return endpoint, nil, err
 	}
-	ws, err := websocket.NewClient(config, conn)
+	header := make(http.Header)
-	if err != nil {
+	if origin != "" {
-		conn.Close()
+		header.Add("origin", origin)
-		return nil, err
 	}
-	return ws, err
+	if endpointURL.User != nil {
+		b64auth := base64.StdEncoding.EncodeToString([]byte(endpointURL.User.String()))
+		header.Add("authorization", "Basic "+b64auth)
+		endpointURL.User = nil
+	}
+	return endpointURL.String(), header, nil
 }
 
-var wsPortMap = map[string]string{"ws": "80", "wss": "443"}
+func newWebsocketCodec(conn *websocket.Conn) ServerCodec {
-
+	conn.SetReadLimit(maxRequestContentLength)
-func wsDialAddress(location *url.URL) string {
+	return newCodec(conn, conn.WriteJSON, conn.ReadJSON)
-	if _, ok := wsPortMap[location.Scheme]; ok {
-		if _, _, err := net.SplitHostPort(location.Host); err != nil {
-			return net.JoinHostPort(location.Host, wsPortMap[location.Scheme])
-		}
-	}
-	return location.Host
-}
-
-func dialContext(ctx context.Context, network, addr string) (net.Conn, error) {
-	d := &net.Dialer{KeepAlive: tcpKeepAliveInterval}
-	return d.DialContext(ctx, network, addr)
-}
-
-func contextDialer(ctx context.Context) *net.Dialer {
-	dialer := &net.Dialer{Cancel: ctx.Done(), KeepAlive: tcpKeepAliveInterval}
-	if deadline, ok := ctx.Deadline(); ok {
-		dialer.Deadline = deadline
-	} else {
-		dialer.Deadline = time.Now().Add(defaultDialTimeout)
-	}
-	return dialer
 }

rpc/websocket_test.go

@@ -16,31 +16,244 @@
 
 package rpc
 
-import "testing"
+import (
+	"context"
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"reflect"
+	"strings"
+	"testing"
+	"time"
 
-func TestWSGetConfigNoAuth(t *testing.T) {
+	"github.com/gorilla/websocket"
-	config, err := wsGetConfig("ws://example.com:1234", "")
+)
+
+func TestWebsocketClientHeaders(t *testing.T) {
+	t.Parallel()
+
+	endpoint, header, err := wsClientHeaders("wss://testuser:test-PASS_01@example.com:1234", "https://example.com")
 	if err != nil {
 		t.Fatalf("wsGetConfig failed: %s", err)
 	}
-	if config.Location.User != nil {
+	if endpoint != "wss://example.com:1234" {
-		t.Fatalf("User should have been stripped from the URL")
-	}
-	if config.Location.Hostname() != "example.com" ||
-		config.Location.Port() != "1234" || config.Location.Scheme != "ws" {
-		t.Fatalf("Unexpected URL: %s", config.Location)
-	}
-}
-
-func TestWSGetConfigWithBasicAuth(t *testing.T) {
-	config, err := wsGetConfig("wss://testuser:test-PASS_01@example.com:1234", "")
-	if err != nil {
-		t.Fatalf("wsGetConfig failed: %s", err)
-	}
-	if config.Location.User != nil {
 		t.Fatal("User should have been stripped from the URL")
 	}
-	if config.Header.Get("Authorization") != "Basic dGVzdHVzZXI6dGVzdC1QQVNTXzAx" {
+	if header.Get("authorization") != "Basic dGVzdHVzZXI6dGVzdC1QQVNTXzAx" {
 		t.Fatal("Basic auth header is incorrect")
 	}
+	if header.Get("origin") != "https://example.com" {
+		t.Fatal("Origin not set")
+	}
+}
+
+// This test checks that the server rejects connections from disallowed origins.
+func TestWebsocketOriginCheck(t *testing.T) {
+	t.Parallel()
+
+	var (
+		srv     = newTestServer()
+		httpsrv = httptest.NewServer(srv.WebsocketHandler([]string{"http://example.com"}))
+		wsURL   = "ws:" + strings.TrimPrefix(httpsrv.URL, "http:")
+	)
+	defer srv.Stop()
+	defer httpsrv.Close()
+
+	client, err := DialWebsocket(context.Background(), wsURL, "http://ekzample.com")
+	if err == nil {
+		client.Close()
+		t.Fatal("no error for wrong origin")
+	}
+	wantErr := wsHandshakeError{websocket.ErrBadHandshake, "403 Forbidden"}
+	if !reflect.DeepEqual(err, wantErr) {
+		t.Fatalf("wrong error for wrong origin: %q", err)
+	}
+
+	// Connections without origin header should work.
+	client, err = DialWebsocket(context.Background(), wsURL, "")
+	if err != nil {
+		t.Fatal("error for empty origin")
+	}
+	client.Close()
+}
+
+// This test checks whether calls exceeding the request size limit are rejected.
+func TestWebsocketLargeCall(t *testing.T) {
+	t.Parallel()
+
+	var (
+		srv     = newTestServer()
+		httpsrv = httptest.NewServer(srv.WebsocketHandler([]string{"*"}))
+		wsURL   = "ws:" + strings.TrimPrefix(httpsrv.URL, "http:")
+	)
+	defer srv.Stop()
+	defer httpsrv.Close()
+
+	client, err := DialWebsocket(context.Background(), wsURL, "")
+	if err != nil {
+		t.Fatalf("can't dial: %v", err)
+	}
+	defer client.Close()
+
+	// This call sends slightly less than the limit and should work.
+	var result Result
+	arg := strings.Repeat("x", maxRequestContentLength-200)
+	if err := client.Call(&result, "test_echo", arg, 1); err != nil {
+		t.Fatalf("valid call didn't work: %v", err)
+	}
+	if result.String != arg {
+		t.Fatal("wrong string echoed")
+	}
+
+	// This call sends twice the allowed size and shouldn't work.
+	arg = strings.Repeat("x", maxRequestContentLength*2)
+	err = client.Call(&result, "test_echo", arg)
+	if err == nil {
+		t.Fatal("no error for too large call")
+	}
+}
+
+// This test checks that client handles WebSocket ping frames correctly.
+func TestClientWebsocketPing(t *testing.T) {
+	t.Parallel()
+
+	var (
+		sendPing    = make(chan struct{})
+		server      = wsPingTestServer(t, sendPing)
+		ctx, cancel = context.WithTimeout(context.Background(), 1*time.Second)
+	)
+	defer cancel()
+	defer server.Shutdown(ctx)
+
+	client, err := DialContext(ctx, "ws://"+server.Addr)
+	if err != nil {
+		t.Fatalf("client dial error: %v", err)
+	}
+	resultChan := make(chan int)
+	sub, err := client.EthSubscribe(ctx, resultChan, "foo")
+	if err != nil {
+		t.Fatalf("client subscribe error: %v", err)
+	}
+
+	// Wait for the context's deadline to be reached before proceeding.
+	// This is important for reproducing https://github.com/ethereum/go-ethereum/issues/19798
+	<-ctx.Done()
+	close(sendPing)
+
+	// Wait for the subscription result.
+	timeout := time.NewTimer(5 * time.Second)
+	for {
+		select {
+		case err := <-sub.Err():
+			t.Error("client subscription error:", err)
+		case result := <-resultChan:
+			t.Log("client got result:", result)
+			return
+		case <-timeout.C:
+			t.Error("didn't get any result within the test timeout")
+			return
+		}
+	}
+}
+
+// wsPingTestServer runs a WebSocket server which accepts a single subscription request.
+// When a value arrives on sendPing, the server sends a ping frame, waits for a matching
+// pong and finally delivers a single subscription result.
+func wsPingTestServer(t *testing.T, sendPing <-chan struct{}) *http.Server {
+	var srv http.Server
+	shutdown := make(chan struct{})
+	srv.RegisterOnShutdown(func() {
+		close(shutdown)
+	})
+	srv.Handler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Upgrade to WebSocket.
+		upgrader := websocket.Upgrader{
+			CheckOrigin: func(r *http.Request) bool { return true },
+		}
+		conn, err := upgrader.Upgrade(w, r, nil)
+		if err != nil {
+			t.Errorf("server WS upgrade error: %v", err)
+			return
+		}
+		defer conn.Close()
+
+		// Handle the connection.
+		wsPingTestHandler(t, conn, shutdown, sendPing)
+	})
+
+	// Start the server.
+	listener, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatal("can't listen:", err)
+	}
+	srv.Addr = listener.Addr().String()
+	go srv.Serve(listener)
+	return &srv
+}
+
+func wsPingTestHandler(t *testing.T, conn *websocket.Conn, shutdown, sendPing <-chan struct{}) {
+	// Canned responses for the eth_subscribe call in TestClientWebsocketPing.
+	const (
+		subResp   = `{"jsonrpc":"2.0","id":1,"result":"0x00"}`
+		subNotify = `{"jsonrpc":"2.0","method":"eth_subscription","params":{"subscription":"0x00","result":1}}`
+	)
+
+	// Handle subscribe request.
+	if _, _, err := conn.ReadMessage(); err != nil {
+		t.Errorf("server read error: %v", err)
+		return
+	}
+	if err := conn.WriteMessage(websocket.TextMessage, []byte(subResp)); err != nil {
+		t.Errorf("server write error: %v", err)
+		return
+	}
+
+	// Read from the connection to process control messages.
+	var pongCh = make(chan string)
+	conn.SetPongHandler(func(d string) error {
+		t.Logf("server got pong: %q", d)
+		pongCh <- d
+		return nil
+	})
+	go func() {
+		for {
+			typ, msg, err := conn.ReadMessage()
+			if err != nil {
+				return
+			}
+			t.Logf("server got message (%d): %q", typ, msg)
+		}
+	}()
+
+	// Write messages.
+	var (
+		sendResponse <-chan time.Time
+		wantPong     string
+	)
+	for {
+		select {
+		case _, open := <-sendPing:
+			if !open {
+				sendPing = nil
+			}
+			t.Logf("server sending ping")
+			conn.WriteMessage(websocket.PingMessage, []byte("ping"))
+			wantPong = "ping"
+		case data := <-pongCh:
+			if wantPong == "" {
+				t.Errorf("unexpected pong")
+			} else if data != wantPong {
+				t.Errorf("got pong with wrong data %q", data)
+			}
+			wantPong = ""
+			sendResponse = time.NewTimer(200 * time.Millisecond).C
+		case <-sendResponse:
+			t.Logf("server sending response")
+			conn.WriteMessage(websocket.TextMessage, []byte(subNotify))
+			sendResponse = nil
+		case <-shutdown:
+			conn.Close()
+			return
+		}
+	}
 }

vendor/github.com/gorilla/websocket/AUTHORS

@@ -0,0 +1,9 @@
+# This is the official list of Gorilla WebSocket authors for copyright
+# purposes.
+#
+# Please keep the list sorted.
+
+Gary Burd <gary@beagledreams.com>
+Google LLC (https://opensource.google.com/)
+Joachim Bauch <mail@joachim-bauch.de>
+

vendor/github.com/gorilla/websocket/LICENSE

@@ -0,0 +1,22 @@
+Copyright (c) 2013 The Gorilla WebSocket Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+  Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+  Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

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

@@ -0,0 +1,64 @@
+# Gorilla WebSocket
+
+[![GoDoc](https://godoc.org/github.com/gorilla/websocket?status.svg)](https://godoc.org/github.com/gorilla/websocket)
+[![CircleCI](https://circleci.com/gh/gorilla/websocket.svg?style=svg)](https://circleci.com/gh/gorilla/websocket)
+
+Gorilla WebSocket is a [Go](http://golang.org/) implementation of the
+[WebSocket](http://www.rfc-editor.org/rfc/rfc6455.txt) protocol.
+
+### Documentation
+
+* [API Reference](http://godoc.org/github.com/gorilla/websocket)
+* [Chat example](https://github.com/gorilla/websocket/tree/master/examples/chat)
+* [Command example](https://github.com/gorilla/websocket/tree/master/examples/command)
+* [Client and server example](https://github.com/gorilla/websocket/tree/master/examples/echo)
+* [File watch example](https://github.com/gorilla/websocket/tree/master/examples/filewatch)
+
+### Status
+
+The Gorilla WebSocket package provides a complete and tested implementation of
+the [WebSocket](http://www.rfc-editor.org/rfc/rfc6455.txt) protocol. The
+package API is stable.
+
+### Installation
+
+    go get github.com/gorilla/websocket
+
+### Protocol Compliance
+
+The Gorilla WebSocket package passes the server tests in the [Autobahn Test
+Suite](https://github.com/crossbario/autobahn-testsuite) using the application in the [examples/autobahn
+subdirectory](https://github.com/gorilla/websocket/tree/master/examples/autobahn).
+
+### Gorilla WebSocket compared with other packages
+
+<table>
+<tr>
+<th></th>
+<th><a href="http://godoc.org/github.com/gorilla/websocket">github.com/gorilla</a></th>
+<th><a href="http://godoc.org/golang.org/x/net/websocket">golang.org/x/net</a></th>
+</tr>
+<tr>
+<tr><td colspan="3"><a href="http://tools.ietf.org/html/rfc6455">RFC 6455</a> Features</td></tr>
+<tr><td>Passes <a href="https://github.com/crossbario/autobahn-testsuite">Autobahn Test Suite</a></td><td><a href="https://github.com/gorilla/websocket/tree/master/examples/autobahn">Yes</a></td><td>No</td></tr>
+<tr><td>Receive <a href="https://tools.ietf.org/html/rfc6455#section-5.4">fragmented</a> message<td>Yes</td><td><a href="https://code.google.com/p/go/issues/detail?id=7632">No</a>, see note 1</td></tr>
+<tr><td>Send <a href="https://tools.ietf.org/html/rfc6455#section-5.5.1">close</a> message</td><td><a href="http://godoc.org/github.com/gorilla/websocket#hdr-Control_Messages">Yes</a></td><td><a href="https://code.google.com/p/go/issues/detail?id=4588">No</a></td></tr>
+<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><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>
+
+Notes:
+
+1. Large messages are fragmented in [Chrome's new WebSocket implementation](http://www.ietf.org/mail-archive/web/hybi/current/msg10503.html).
+2. The application can get the type of a received data message by implementing
+   a [Codec marshal](http://godoc.org/golang.org/x/net/websocket#Codec.Marshal)
+   function.
+3. The go.net io.Reader and io.Writer operate across WebSocket frame boundaries.
+  Read returns when the input buffer is full or a frame boundary is
+  encountered. Each call to Write sends a single frame message. The Gorilla
+  io.Reader and io.WriteCloser operate on a single WebSocket message.
+

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

@@ -0,0 +1,395 @@
+// Copyright 2013 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 (
+	"bytes"
+	"context"
+	"crypto/tls"
+	"errors"
+	"io"
+	"io/ioutil"
+	"net"
+	"net/http"
+	"net/http/httptrace"
+	"net/url"
+	"strings"
+	"time"
+)
+
+// ErrBadHandshake is returned when the server response to opening handshake is
+// 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
+// (Cookie). Use the response.Header to get the selected subprotocol
+// (Sec-WebSocket-Protocol) and cookies (Set-Cookie).
+//
+// If the WebSocket handshake fails, ErrBadHandshake is returned along with a
+// non-nil *http.Response so that callers can handle redirects, authentication,
+// etc.
+//
+// Deprecated: Use Dialer instead.
+func NewClient(netConn net.Conn, u *url.URL, requestHeader http.Header, readBufSize, writeBufSize int) (c *Conn, response *http.Response, err error) {
+	d := Dialer{
+		ReadBufferSize:  readBufSize,
+		WriteBufferSize: writeBufSize,
+		NetDial: func(net, addr string) (net.Conn, error) {
+			return netConn, nil
+		},
+	}
+	return d.Dial(u.String(), requestHeader)
+}
+
+// A Dialer contains options for connecting to WebSocket server.
+type Dialer struct {
+	// NetDial specifies the dial function for creating TCP connections. If
+	// NetDial is nil, net.Dial is used.
+	NetDial func(network, addr string) (net.Conn, error)
+
+	// NetDialContext specifies the dial function for creating TCP connections. If
+	// NetDialContext is nil, net.DialContext is used.
+	NetDialContext func(ctx context.Context, network, addr string) (net.Conn, error)
+
+	// Proxy specifies a function to return a proxy for a given
+	// Request. If the function returns a non-nil error, the
+	// request is aborted with the provided error.
+	// If Proxy is nil or returns a nil *URL, no proxy is used.
+	Proxy func(*http.Request) (*url.URL, error)
+
+	// TLSClientConfig specifies the TLS configuration to use with tls.Client.
+	// If nil, the default configuration is used.
+	TLSClientConfig *tls.Config
+
+	// HandshakeTimeout specifies the duration for the handshake to complete.
+	HandshakeTimeout time.Duration
+
+	// ReadBufferSize and WriteBufferSize specify I/O buffer sizes in bytes. If a buffer
+	// size is zero, then a useful default size is used. The I/O buffer sizes
+	// do not limit the size of the messages that can be sent or received.
+	ReadBufferSize, WriteBufferSize int
+
+	// WriteBufferPool is a pool of buffers for write operations. If the value
+	// is not set, then write buffers are allocated to the connection for the
+	// lifetime of the connection.
+	//
+	// A pool is most useful when the application has a modest volume of writes
+	// across a large number of connections.
+	//
+	// Applications should use a single pool for each unique value of
+	// WriteBufferSize.
+	WriteBufferPool BufferPool
+
+	// 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
+}
+
+// Dial creates a new client connection by calling DialContext with a background context.
+func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Response, error) {
+	return d.DialContext(context.Background(), urlStr, requestHeader)
+}
+
+var errMalformedURL = errors.New("malformed ws or wss URL")
+
+func hostPortNoPort(u *url.URL) (hostPort, hostNoPort string) {
+	hostPort = u.Host
+	hostNoPort = u.Host
+	if i := strings.LastIndex(u.Host, ":"); i > strings.LastIndex(u.Host, "]") {
+		hostNoPort = hostNoPort[:i]
+	} else {
+		switch u.Scheme {
+		case "wss":
+			hostPort += ":443"
+		case "https":
+			hostPort += ":443"
+		default:
+			hostPort += ":80"
+		}
+	}
+	return hostPort, hostNoPort
+}
+
+// DefaultDialer is a dialer with all fields set to the default values.
+var DefaultDialer = &Dialer{
+	Proxy:            http.ProxyFromEnvironment,
+	HandshakeTimeout: 45 * time.Second,
+}
+
+// nilDialer is dialer to use when receiver is nil.
+var nilDialer = *DefaultDialer
+
+// DialContext creates a new client connection. Use requestHeader to specify the
+// origin (Origin), subprotocols (Sec-WebSocket-Protocol) and cookies (Cookie).
+// Use the response.Header to get the selected subprotocol
+// (Sec-WebSocket-Protocol) and cookies (Set-Cookie).
+//
+// The context will be used in the request and in the Dialer.
+//
+// If the WebSocket handshake fails, ErrBadHandshake is returned along with a
+// non-nil *http.Response so that callers can handle redirects, authentication,
+// etcetera. The response body may not contain the entire response and does not
+// need to be closed by the application.
+func (d *Dialer) DialContext(ctx context.Context, urlStr string, requestHeader http.Header) (*Conn, *http.Response, error) {
+	if d == nil {
+		d = &nilDialer
+	}
+
+	challengeKey, err := generateChallengeKey()
+	if err != nil {
+		return nil, nil, err
+	}
+
+	u, err := url.Parse(urlStr)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	switch u.Scheme {
+	case "ws":
+		u.Scheme = "http"
+	case "wss":
+		u.Scheme = "https"
+	default:
+		return nil, nil, errMalformedURL
+	}
+
+	if u.User != nil {
+		// User name and password are not allowed in websocket URIs.
+		return nil, nil, errMalformedURL
+	}
+
+	req := &http.Request{
+		Method:     "GET",
+		URL:        u,
+		Proto:      "HTTP/1.1",
+		ProtoMajor: 1,
+		ProtoMinor: 1,
+		Header:     make(http.Header),
+		Host:       u.Host,
+	}
+	req = req.WithContext(ctx)
+
+	// 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
+	// method canonicalizes the header names.
+	req.Header["Upgrade"] = []string{"websocket"}
+	req.Header["Connection"] = []string{"Upgrade"}
+	req.Header["Sec-WebSocket-Key"] = []string{challengeKey}
+	req.Header["Sec-WebSocket-Version"] = []string{"13"}
+	if len(d.Subprotocols) > 0 {
+		req.Header["Sec-WebSocket-Protocol"] = []string{strings.Join(d.Subprotocols, ", ")}
+	}
+	for k, vs := range requestHeader {
+		switch {
+		case k == "Host":
+			if len(vs) > 0 {
+				req.Host = vs[0]
+			}
+		case k == "Upgrade" ||
+			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)
+		case k == "Sec-Websocket-Protocol":
+			req.Header["Sec-WebSocket-Protocol"] = vs
+		default:
+			req.Header[k] = vs
+		}
+	}
+
+	if d.EnableCompression {
+		req.Header["Sec-WebSocket-Extensions"] = []string{"permessage-deflate; server_no_context_takeover; client_no_context_takeover"}
+	}
+
+	if d.HandshakeTimeout != 0 {
+		var cancel func()
+		ctx, cancel = context.WithTimeout(ctx, d.HandshakeTimeout)
+		defer cancel()
+	}
+
+	// Get network dial function.
+	var netDial func(network, add string) (net.Conn, error)
+
+	if d.NetDialContext != nil {
+		netDial = func(network, addr string) (net.Conn, error) {
+			return d.NetDialContext(ctx, network, addr)
+		}
+	} else if d.NetDial != nil {
+		netDial = d.NetDial
+	} else {
+		netDialer := &net.Dialer{}
+		netDial = func(network, addr string) (net.Conn, error) {
+			return netDialer.DialContext(ctx, network, addr)
+		}
+	}
+
+	// If needed, wrap the dial function to set the connection deadline.
+	if deadline, ok := ctx.Deadline(); ok {
+		forwardDial := netDial
+		netDial = func(network, addr string) (net.Conn, error) {
+			c, err := forwardDial(network, addr)
+			if err != nil {
+				return nil, err
+			}
+			err = c.SetDeadline(deadline)
+			if err != nil {
+				c.Close()
+				return nil, err
+			}
+			return c, nil
+		}
+	}
+
+	// If needed, wrap the dial function to connect through a proxy.
+	if d.Proxy != nil {
+		proxyURL, err := d.Proxy(req)
+		if err != nil {
+			return nil, nil, err
+		}
+		if proxyURL != nil {
+			dialer, err := proxy_FromURL(proxyURL, netDialerFunc(netDial))
+			if err != nil {
+				return nil, nil, err
+			}
+			netDial = dialer.Dial
+		}
+	}
+
+	hostPort, hostNoPort := hostPortNoPort(u)
+	trace := httptrace.ContextClientTrace(ctx)
+	if trace != nil && trace.GetConn != nil {
+		trace.GetConn(hostPort)
+	}
+
+	netConn, err := netDial("tcp", hostPort)
+	if trace != nil && trace.GotConn != nil {
+		trace.GotConn(httptrace.GotConnInfo{
+			Conn: netConn,
+		})
+	}
+	if err != nil {
+		return nil, nil, err
+	}
+
+	defer func() {
+		if netConn != nil {
+			netConn.Close()
+		}
+	}()
+
+	if u.Scheme == "https" {
+		cfg := cloneTLSConfig(d.TLSClientConfig)
+		if cfg.ServerName == "" {
+			cfg.ServerName = hostNoPort
+		}
+		tlsConn := tls.Client(netConn, cfg)
+		netConn = tlsConn
+
+		var err error
+		if trace != nil {
+			err = doHandshakeWithTrace(trace, tlsConn, cfg)
+		} else {
+			err = doHandshake(tlsConn, cfg)
+		}
+
+		if err != nil {
+			return nil, nil, err
+		}
+	}
+
+	conn := newConn(netConn, false, d.ReadBufferSize, d.WriteBufferSize, d.WriteBufferPool, nil, nil)
+
+	if err := req.Write(netConn); err != nil {
+		return nil, nil, err
+	}
+
+	if trace != nil && trace.GotFirstResponseByte != nil {
+		if peek, err := conn.br.Peek(1); err == nil && len(peek) == 1 {
+			trace.GotFirstResponseByte()
+		}
+	}
+
+	resp, err := http.ReadResponse(conn.br, req)
+	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") ||
+		resp.Header.Get("Sec-Websocket-Accept") != computeAcceptKey(challengeKey) {
+		// Before closing the network connection on return from this
+		// function, slurp up some of the response to aid application
+		// debugging.
+		buf := make([]byte, 1024)
+		n, _ := io.ReadFull(resp.Body, buf)
+		resp.Body = ioutil.NopCloser(bytes.NewReader(buf[:n]))
+		return nil, resp, ErrBadHandshake
+	}
+
+	for _, ext := range parseExtensions(resp.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")
+
+	netConn.SetDeadline(time.Time{})
+	netConn = nil // to avoid close in defer.
+	return conn, resp, nil
+}
+
+func doHandshake(tlsConn *tls.Conn, cfg *tls.Config) error {
+	if err := tlsConn.Handshake(); err != nil {
+		return err
+	}
+	if !cfg.InsecureSkipVerify {
+		if err := tlsConn.VerifyHostname(cfg.ServerName); err != nil {
+			return err
+		}
+	}
+	return nil
+}

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

@@ -0,0 +1,16 @@
+// Copyright 2013 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 go1.8
+
+package websocket
+
+import "crypto/tls"
+
+func cloneTLSConfig(cfg *tls.Config) *tls.Config {
+	if cfg == nil {
+		return &tls.Config{}
+	}
+	return cfg.Clone()
+}

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

@@ -0,0 +1,38 @@
+// Copyright 2013 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 !go1.8
+
+package websocket
+
+import "crypto/tls"
+
+// 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 +1,148 @@
+// 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"
+)
+
+const (
+	minCompressionLevel     = -2 // flate.HuffmanOnly not defined in Go < 1.6
+	maxCompressionLevel     = flate.BestCompression
+	defaultCompressionLevel = 1
+)
+
+var (
+	flateWriterPools [maxCompressionLevel - minCompressionLevel + 1]sync.Pool
+	flateReaderPool  = sync.Pool{New: func() interface{} {
+		return flate.NewReader(nil)
+	}}
+)
+
+func decompressNoContextTakeover(r io.Reader) io.ReadCloser {
+	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"
+
+	fr, _ := flateReaderPool.Get().(io.ReadCloser)
+	fr.(flate.Resetter).Reset(io.MultiReader(r, strings.NewReader(tail)), nil)
+	return &flateReadWrapper{fr}
+}
+
+func isValidCompressionLevel(level int) bool {
+	return minCompressionLevel <= level && level <= maxCompressionLevel
+}
+
+func compressNoContextTakeover(w io.WriteCloser, level int) io.WriteCloser {
+	p := &flateWriterPools[level-minCompressionLevel]
+	tw := &truncWriter{w: w}
+	fw, _ := p.Get().(*flate.Writer)
+	if fw == nil {
+		fw, _ = flate.NewWriter(tw, level)
+	} else {
+		fw.Reset(tw)
+	}
+	return &flateWriteWrapper{fw: fw, tw: tw, p: p}
+}
+
+// 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 flateWriteWrapper struct {
+	fw *flate.Writer
+	tw *truncWriter
+	p  *sync.Pool
+}
+
+func (w *flateWriteWrapper) Write(p []byte) (int, error) {
+	if w.fw == nil {
+		return 0, errWriteClosed
+	}
+	return w.fw.Write(p)
+}
+
+func (w *flateWriteWrapper) Close() error {
+	if w.fw == nil {
+		return errWriteClosed
+	}
+	err1 := w.fw.Flush()
+	w.p.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
+}
+
+type flateReadWrapper struct {
+	fr io.ReadCloser
+}
+
+func (r *flateReadWrapper) Read(p []byte) (int, error) {
+	if r.fr == nil {
+		return 0, io.ErrClosedPipe
+	}
+	n, err := r.fr.Read(p)
+	if err == io.EOF {
+		// Preemptively place the reader back in the pool. This helps with
+		// scenarios where the application does not call NextReader() soon after
+		// this final read.
+		r.Close()
+	}
+	return n, err
+}
+
+func (r *flateReadWrapper) Close() error {
+	if r.fr == nil {
+		return io.ErrClosedPipe
+	}
+	err := r.fr.Close()
+	flateReaderPool.Put(r.fr)
+	r.fr = nil
+	return err
+}

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

@@ -0,0 +1,15 @@
+// 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 go1.8
+
+package websocket
+
+import "net"
+
+func (c *Conn) writeBufs(bufs ...[]byte) error {
+	b := net.Buffers(bufs)
+	_, err := b.WriteTo(c.conn)
+	return err
+}

vendor/github.com/gorilla/websocket/conn_write_legacy.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 !go1.8
+
+package websocket
+
+func (c *Conn) writeBufs(bufs ...[]byte) error {
+	for _, buf := range bufs {
+		if len(buf) > 0 {
+			if _, err := c.conn.Write(buf); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}

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

@@ -0,0 +1,227 @@
+// Copyright 2013 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 implements the WebSocket protocol defined in RFC 6455.
+//
+// Overview
+//
+// The Conn type represents a WebSocket connection. A server application calls
+// the Upgrader.Upgrade method from an HTTP request handler to get a *Conn:
+//
+//  var upgrader = websocket.Upgrader{
+//      ReadBufferSize:  1024,
+//      WriteBufferSize: 1024,
+//  }
+//
+//  func handler(w http.ResponseWriter, r *http.Request) {
+//      conn, err := upgrader.Upgrade(w, r, nil)
+//      if err != nil {
+//          log.Println(err)
+//          return
+//      }
+//      ... Use conn to send and receive messages.
+//  }
+//
+// Call the connection's WriteMessage and ReadMessage methods to send and
+// receive messages as a slice of bytes. This snippet of code shows how to echo
+// messages using these methods:
+//
+//  for {
+//      messageType, p, err := conn.ReadMessage()
+//      if err != nil {
+//          log.Println(err)
+//          return
+//      }
+//      if err := conn.WriteMessage(messageType, p); err != nil {
+//          log.Println(err)
+//          return
+//      }
+//  }
+//
+// In above snippet of code, p is a []byte and messageType is an int with value
+// websocket.BinaryMessage or websocket.TextMessage.
+//
+// An application can also send and receive messages using the io.WriteCloser
+// and io.Reader interfaces. To send a message, call the connection NextWriter
+// method to get an io.WriteCloser, write the message to the writer and close
+// the writer when done. To receive a message, call the connection NextReader
+// method to get an io.Reader and read until io.EOF is returned. This snippet
+// shows how to echo messages using the NextWriter and NextReader methods:
+//
+//  for {
+//      messageType, r, err := conn.NextReader()
+//      if err != nil {
+//          return
+//      }
+//      w, err := conn.NextWriter(messageType)
+//      if err != nil {
+//          return err
+//      }
+//      if _, err := io.Copy(w, r); err != nil {
+//          return err
+//      }
+//      if err := w.Close(); err != nil {
+//          return err
+//      }
+//  }
+//
+// Data Messages
+//
+// The WebSocket protocol distinguishes between text and binary data messages.
+// Text messages are interpreted as UTF-8 encoded text. The interpretation of
+// binary messages is left to the application.
+//
+// This package uses the TextMessage and BinaryMessage integer constants to
+// identify the two data message types. The ReadMessage and NextReader methods
+// return the type of the received message. The messageType argument to the
+// WriteMessage and NextWriter methods specifies the type of a sent message.
+//
+// It is the application's responsibility to ensure that text messages are
+// valid UTF-8 encoded text.
+//
+// Control Messages
+//
+// The WebSocket protocol defines three types of control messages: close, ping
+// and pong. Call the connection WriteControl, WriteMessage or NextWriter
+// methods to send a control message to the peer.
+//
+// Connections handle received close messages by calling the handler function
+// set with the SetCloseHandler method and by returning a *CloseError from the
+// NextReader, ReadMessage or the message Read method. The default close
+// handler sends a close message to the peer.
+//
+// Connections handle received ping messages by calling the handler function
+// set with the SetPingHandler method. The default ping handler sends a pong
+// message to the peer.
+//
+// Connections handle received pong messages by calling the handler function
+// set with the SetPongHandler method. The default pong handler does nothing.
+// If an application sends ping messages, then the application should set a
+// pong handler to receive the corresponding pong.
+//
+// The control message handler functions are called from the NextReader,
+// ReadMessage and message reader Read methods. The default close and ping
+// handlers can block these methods for a short time when the handler writes to
+// the connection.
+//
+// The application must read the connection to process close, ping and pong
+// 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) {
+//      for {
+//          if _, _, err := c.NextReader(); err != nil {
+//              c.Close()
+//              break
+//          }
+//      }
+//  }
+//
+// Concurrency
+//
+// Connections support one concurrent reader and one concurrent writer.
+//
+// Applications are responsible for ensuring that no more than one goroutine
+// calls the write methods (NextWriter, SetWriteDeadline, WriteMessage,
+// WriteJSON, EnableWriteCompression, SetCompressionLevel) concurrently and
+// that no more than one goroutine calls the read methods (NextReader,
+// SetReadDeadline, ReadMessage, ReadJSON, SetPongHandler, SetPingHandler)
+// concurrently.
+//
+// The Close and WriteControl methods can be called concurrently with all other
+// methods.
+//
+// Origin Considerations
+//
+// Web browsers allow Javascript applications to open a WebSocket connection to
+// any host. It's up to the server to enforce an origin policy using the Origin
+// request header sent by the browser.
+//
+// The Upgrader calls the function specified in the CheckOrigin field to check
+// the origin. If the CheckOrigin function returns false, then the Upgrade
+// method fails the WebSocket handshake with HTTP status 403.
+//
+// If the CheckOrigin field is nil, then the Upgrader uses a safe default: fail
+// the handshake if the Origin request header is present and the Origin host is
+// not equal to the Host request header.
+//
+// The deprecated package-level Upgrade function does not perform origin
+// checking. The application is responsible for checking the Origin header
+// before calling the Upgrade function.
+//
+// Buffers
+//
+// Connections buffer network input and output to reduce the number
+// of system calls when reading or writing messages.
+//
+// Write buffers are also used for constructing WebSocket frames. See RFC 6455,
+// Section 5 for a discussion of message framing. A WebSocket frame header is
+// written to the network each time a write buffer is flushed to the network.
+// Decreasing the size of the write buffer can increase the amount of framing
+// overhead on the connection.
+//
+// The buffer sizes in bytes are specified by the ReadBufferSize and
+// WriteBufferSize fields in the Dialer and Upgrader. The Dialer uses a default
+// size of 4096 when a buffer size field is set to zero. The Upgrader reuses
+// buffers created by the HTTP server when a buffer size field is set to zero.
+// The HTTP server buffers have a size of 4096 at the time of this writing.
+//
+// The buffer sizes do not limit the size of a message that can be read or
+// written by a connection.
+//
+// Buffers are held for the lifetime of the connection by default. If the
+// Dialer or Upgrader WriteBufferPool field is set, then a connection holds the
+// write buffer only when writing a message.
+//
+// Applications should tune the buffer sizes to balance memory use and
+// performance. Increasing the buffer size uses more memory, but can reduce the
+// number of system calls to read or write the network. In the case of writing,
+// increasing the buffer size can reduce the number of frame headers written to
+// the network.
+//
+// Some guidelines for setting buffer parameters are:
+//
+// Limit the buffer sizes to the maximum expected message size. Buffers larger
+// than the largest message do not provide any benefit.
+//
+// Depending on the distribution of message sizes, setting the buffer size to
+// to a value less than the maximum expected message size can greatly reduce
+// memory use with a small impact on performance. Here's an example: If 99% of
+// the messages are smaller than 256 bytes and the maximum message size is 512
+// bytes, then a buffer size of 256 bytes will result in 1.01 more system calls
+// than a buffer size of 512 bytes. The memory savings is 50%.
+//
+// A write buffer pool is useful when the application has a modest number
+// writes over a large number of connections. when buffers are pooled, a larger
+// buffer size has a reduced impact on total memory use and has the benefit of
+// reducing system calls and frame overhead.
+//
+// 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.
+//
+//  var upgrader = websocket.Upgrader{
+//      EnableCompression: true,
+//  }
+//
+// 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(false)
+//
+// 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/go.mod

@@ -0,0 +1 @@
+module github.com/gorilla/websocket

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

@@ -0,0 +1,2 @@
+github.com/gorilla/websocket v1.4.0 h1:WDFjx/TMzVgy9VdMMQi2K2Emtwi2QcUQsztZ/zLaH/Q=
+github.com/gorilla/websocket v1.4.0/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoAMk2YaljkQ=

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

@@ -0,0 +1,42 @@
+// Copyright 2019 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 (
+	"io"
+	"strings"
+)
+
+// JoinMessages concatenates received messages to create a single io.Reader.
+// The string term is appended to each message. The returned reader does not
+// support concurrent calls to the Read method.
+func JoinMessages(c *Conn, term string) io.Reader {
+	return &joinReader{c: c, term: term}
+}
+
+type joinReader struct {
+	c    *Conn
+	term string
+	r    io.Reader
+}
+
+func (r *joinReader) Read(p []byte) (int, error) {
+	if r.r == nil {
+		var err error
+		_, r.r, err = r.c.NextReader()
+		if err != nil {
+			return 0, err
+		}
+		if r.term != "" {
+			r.r = io.MultiReader(r.r, strings.NewReader(r.term))
+		}
+	}
+	n, err := r.r.Read(p)
+	if err == io.EOF {
+		err = nil
+		r.r = nil
+	}
+	return n, err
+}

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

@@ -0,0 +1,60 @@
+// Copyright 2013 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 (
+	"encoding/json"
+	"io"
+)
+
+// WriteJSON writes the JSON encoding of v as a message.
+//
+// Deprecated: Use c.WriteJSON instead.
+func WriteJSON(c *Conn, v interface{}) error {
+	return c.WriteJSON(v)
+}
+
+// WriteJSON writes the JSON encoding of v as a message.
+//
+// See the documentation for encoding/json Marshal for details about the
+// conversion of Go values to JSON.
+func (c *Conn) WriteJSON(v interface{}) error {
+	w, err := c.NextWriter(TextMessage)
+	if err != nil {
+		return err
+	}
+	err1 := json.NewEncoder(w).Encode(v)
+	err2 := w.Close()
+	if err1 != nil {
+		return err1
+	}
+	return err2
+}
+
+// ReadJSON reads the next JSON-encoded message from the connection and stores
+// it in the value pointed to by v.
+//
+// Deprecated: Use c.ReadJSON instead.
+func ReadJSON(c *Conn, v interface{}) error {
+	return c.ReadJSON(v)
+}
+
+// ReadJSON reads the next JSON-encoded message from the connection and stores
+// it in the value pointed to by v.
+//
+// See the documentation for the encoding/json Unmarshal function for details
+// about the conversion of JSON to a Go value.
+func (c *Conn) ReadJSON(v interface{}) error {
+	_, r, err := c.NextReader()
+	if err != nil {
+		return err
+	}
+	err = json.NewDecoder(r).Decode(v)
+	if err == io.EOF {
+		// One value is expected in the message.
+		err = io.ErrUnexpectedEOF
+	}
+	return err
+}

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

@@ -0,0 +1,54 @@
+// 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 !appengine
+
+package websocket
+
+import "unsafe"
+
+const wordSize = int(unsafe.Sizeof(uintptr(0)))
+
+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/mask_safe.go

@@ -0,0 +1,15 @@
+// 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 appengine
+
+package websocket
+
+func maskBytes(key [4]byte, pos int, b []byte) int {
+	for i := range b {
+		b[i] ^= key[pos&3]
+		pos++
+	}
+	return pos & 3
+}

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

@@ -0,0 +1,102 @@
+// 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 (
+	"bytes"
+	"net"
+	"sync"
+	"time"
+)
+
+// PreparedMessage caches on the wire representations of a message payload.
+// Use PreparedMessage to efficiently send a message payload to multiple
+// connections. PreparedMessage is especially useful when compression is used
+// because the CPU and memory expensive compression operation can be executed
+// once for a given set of compression options.
+type PreparedMessage struct {
+	messageType int
+	data        []byte
+	mu          sync.Mutex
+	frames      map[prepareKey]*preparedFrame
+}
+
+// prepareKey defines a unique set of options to cache prepared frames in PreparedMessage.
+type prepareKey struct {
+	isServer         bool
+	compress         bool
+	compressionLevel int
+}
+
+// preparedFrame contains data in wire representation.
+type preparedFrame struct {
+	once sync.Once
+	data []byte
+}
+
+// NewPreparedMessage returns an initialized PreparedMessage. You can then send
+// it to connection using WritePreparedMessage method. Valid wire
+// representation will be calculated lazily only once for a set of current
+// connection options.
+func NewPreparedMessage(messageType int, data []byte) (*PreparedMessage, error) {
+	pm := &PreparedMessage{
+		messageType: messageType,
+		frames:      make(map[prepareKey]*preparedFrame),
+		data:        data,
+	}
+
+	// Prepare a plain server frame.
+	_, frameData, err := pm.frame(prepareKey{isServer: true, compress: false})
+	if err != nil {
+		return nil, err
+	}
+
+	// To protect against caller modifying the data argument, remember the data
+	// copied to the plain server frame.
+	pm.data = frameData[len(frameData)-len(data):]
+	return pm, nil
+}
+
+func (pm *PreparedMessage) frame(key prepareKey) (int, []byte, error) {
+	pm.mu.Lock()
+	frame, ok := pm.frames[key]
+	if !ok {
+		frame = &preparedFrame{}
+		pm.frames[key] = frame
+	}
+	pm.mu.Unlock()
+
+	var err error
+	frame.once.Do(func() {
+		// Prepare a frame using a 'fake' connection.
+		// TODO: Refactor code in conn.go to allow more direct construction of
+		// the frame.
+		mu := make(chan bool, 1)
+		mu <- true
+		var nc prepareConn
+		c := &Conn{
+			conn:                   &nc,
+			mu:                     mu,
+			isServer:               key.isServer,
+			compressionLevel:       key.compressionLevel,
+			enableWriteCompression: true,
+			writeBuf:               make([]byte, defaultWriteBufferSize+maxFrameHeaderSize),
+		}
+		if key.compress {
+			c.newCompressionWriter = compressNoContextTakeover
+		}
+		err = c.WriteMessage(pm.messageType, pm.data)
+		frame.data = nc.buf.Bytes()
+	})
+	return pm.messageType, frame.data, err
+}
+
+type prepareConn struct {
+	buf bytes.Buffer
+	net.Conn
+}
+
+func (pc *prepareConn) Write(p []byte) (int, error)        { return pc.buf.Write(p) }
+func (pc *prepareConn) SetWriteDeadline(t time.Time) error { return nil }

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

@@ -0,0 +1,77 @@
+// 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 (
+	"bufio"
+	"encoding/base64"
+	"errors"
+	"net"
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+type netDialerFunc func(network, addr string) (net.Conn, error)
+
+func (fn netDialerFunc) Dial(network, addr string) (net.Conn, error) {
+	return fn(network, addr)
+}
+
+func init() {
+	proxy_RegisterDialerType("http", func(proxyURL *url.URL, forwardDialer proxy_Dialer) (proxy_Dialer, error) {
+		return &httpProxyDialer{proxyURL: proxyURL, forwardDial: forwardDialer.Dial}, nil
+	})
+}
+
+type httpProxyDialer struct {
+	proxyURL    *url.URL
+	forwardDial func(network, addr string) (net.Conn, error)
+}
+
+func (hpd *httpProxyDialer) Dial(network string, addr string) (net.Conn, error) {
+	hostPort, _ := hostPortNoPort(hpd.proxyURL)
+	conn, err := hpd.forwardDial(network, hostPort)
+	if err != nil {
+		return nil, err
+	}
+
+	connectHeader := make(http.Header)
+	if user := hpd.proxyURL.User; user != nil {
+		proxyUser := user.Username()
+		if proxyPassword, passwordSet := user.Password(); passwordSet {
+			credential := base64.StdEncoding.EncodeToString([]byte(proxyUser + ":" + proxyPassword))
+			connectHeader.Set("Proxy-Authorization", "Basic "+credential)
+		}
+	}
+
+	connectReq := &http.Request{
+		Method: "CONNECT",
+		URL:    &url.URL{Opaque: addr},
+		Host:   addr,
+		Header: connectHeader,
+	}
+
+	if err := connectReq.Write(conn); err != nil {
+		conn.Close()
+		return nil, err
+	}
+
+	// Read response. It's OK to use and discard buffered reader here becaue
+	// the remote server does not speak until spoken to.
+	br := bufio.NewReader(conn)
+	resp, err := http.ReadResponse(br, connectReq)
+	if err != nil {
+		conn.Close()
+		return nil, err
+	}
+
+	if resp.StatusCode != 200 {
+		conn.Close()
+		f := strings.SplitN(resp.Status, " ", 2)
+		return nil, errors.New(f[1])
+	}
+	return conn, nil
+}

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

@@ -0,0 +1,363 @@
+// Copyright 2013 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 (
+	"bufio"
+	"errors"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+)
+
+// HandshakeError describes an error with the handshake from the peer.
+type HandshakeError struct {
+	message string
+}
+
+func (e HandshakeError) Error() string { return e.message }
+
+// Upgrader specifies parameters for upgrading an HTTP connection to a
+// WebSocket connection.
+type Upgrader struct {
+	// HandshakeTimeout specifies the duration for the handshake to complete.
+	HandshakeTimeout time.Duration
+
+	// ReadBufferSize and WriteBufferSize specify I/O buffer sizes in bytes. If a buffer
+	// size is zero, then buffers allocated by the HTTP server are used. The
+	// I/O buffer sizes do not limit the size of the messages that can be sent
+	// or received.
+	ReadBufferSize, WriteBufferSize int
+
+	// WriteBufferPool is a pool of buffers for write operations. If the value
+	// is not set, then write buffers are allocated to the connection for the
+	// lifetime of the connection.
+	//
+	// A pool is most useful when the application has a modest volume of writes
+	// across a large number of connections.
+	//
+	// Applications should use a single pool for each unique value of
+	// WriteBufferSize.
+	WriteBufferPool BufferPool
+
+	// Subprotocols specifies the server's supported protocols in order of
+	// preference. If this field is not nil, then the Upgrade method negotiates a
+	// subprotocol by selecting the first match in this list with a protocol
+	// requested by the client. If there's no match, then no protocol is
+	// negotiated (the Sec-Websocket-Protocol header is not included in the
+	// handshake response).
+	Subprotocols []string
+
+	// Error specifies the function for generating HTTP error responses. If Error
+	// is nil, then http.Error is used to generate the HTTP response.
+	Error func(w http.ResponseWriter, r *http.Request, status int, reason error)
+
+	// CheckOrigin returns true if the request Origin header is acceptable. If
+	// CheckOrigin is nil, then a safe default is used: return false if the
+	// Origin request header is present and the origin host is not equal to
+	// request Host header.
+	//
+	// A CheckOrigin function should carefully validate the request origin to
+	// prevent cross-site request forgery.
+	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) {
+	err := HandshakeError{reason}
+	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
+}
+
+// checkSameOrigin returns true if the origin is not set or is equal to the request host.
+func checkSameOrigin(r *http.Request) bool {
+	origin := r.Header["Origin"]
+	if len(origin) == 0 {
+		return true
+	}
+	u, err := url.Parse(origin[0])
+	if err != nil {
+		return false
+	}
+	return equalASCIIFold(u.Host, r.Host)
+}
+
+func (u *Upgrader) selectSubprotocol(r *http.Request, responseHeader http.Header) string {
+	if u.Subprotocols != nil {
+		clientProtocols := Subprotocols(r)
+		for _, serverProtocol := range u.Subprotocols {
+			for _, clientProtocol := range clientProtocols {
+				if clientProtocol == serverProtocol {
+					return clientProtocol
+				}
+			}
+		}
+	} else if responseHeader != nil {
+		return responseHeader.Get("Sec-Websocket-Protocol")
+	}
+	return ""
+}
+
+// Upgrade upgrades the HTTP server connection to the WebSocket protocol.
+//
+// The responseHeader is included in the response to the client's upgrade
+// request. Use the responseHeader to specify cookies (Set-Cookie) and the
+// application negotiated subprotocol (Sec-WebSocket-Protocol).
+//
+// If the upgrade fails, then Upgrade replies to the client with an HTTP error
+// response.
+func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeader http.Header) (*Conn, error) {
+	const badHandshake = "websocket: the client is not using the websocket protocol: "
+
+	if !tokenListContainsValue(r.Header, "Connection", "upgrade") {
+		return u.returnError(w, r, http.StatusBadRequest, badHandshake+"'upgrade' token not found in 'Connection' header")
+	}
+
+	if !tokenListContainsValue(r.Header, "Upgrade", "websocket") {
+		return u.returnError(w, r, http.StatusBadRequest, badHandshake+"'websocket' token not found in 'Upgrade' header")
+	}
+
+	if r.Method != "GET" {
+		return u.returnError(w, r, http.StatusMethodNotAllowed, badHandshake+"request method is not GET")
+	}
+
+	if !tokenListContainsValue(r.Header, "Sec-Websocket-Version", "13") {
+		return u.returnError(w, r, http.StatusBadRequest, "websocket: unsupported version: 13 not found in 'Sec-Websocket-Version' header")
+	}
+
+	if _, ok := responseHeader["Sec-Websocket-Extensions"]; ok {
+		return u.returnError(w, r, http.StatusInternalServerError, "websocket: application specific 'Sec-WebSocket-Extensions' headers are unsupported")
+	}
+
+	checkOrigin := u.CheckOrigin
+	if checkOrigin == nil {
+		checkOrigin = checkSameOrigin
+	}
+	if !checkOrigin(r) {
+		return u.returnError(w, r, http.StatusForbidden, "websocket: request origin not allowed by Upgrader.CheckOrigin")
+	}
+
+	challengeKey := r.Header.Get("Sec-Websocket-Key")
+	if challengeKey == "" {
+		return u.returnError(w, r, http.StatusBadRequest, "websocket: not a websocket handshake: `Sec-WebSocket-Key' header is missing or blank")
+	}
+
+	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
+		}
+	}
+
+	h, ok := w.(http.Hijacker)
+	if !ok {
+		return u.returnError(w, r, http.StatusInternalServerError, "websocket: response does not implement http.Hijacker")
+	}
+	var brw *bufio.ReadWriter
+	netConn, brw, err := h.Hijack()
+	if err != nil {
+		return u.returnError(w, r, http.StatusInternalServerError, err.Error())
+	}
+
+	if brw.Reader.Buffered() > 0 {
+		netConn.Close()
+		return nil, errors.New("websocket: client sent data before handshake is complete")
+	}
+
+	var br *bufio.Reader
+	if u.ReadBufferSize == 0 && bufioReaderSize(netConn, brw.Reader) > 256 {
+		// Reuse hijacked buffered reader as connection reader.
+		br = brw.Reader
+	}
+
+	buf := bufioWriterBuffer(netConn, brw.Writer)
+
+	var writeBuf []byte
+	if u.WriteBufferPool == nil && u.WriteBufferSize == 0 && len(buf) >= maxFrameHeaderSize+256 {
+		// Reuse hijacked write buffer as connection buffer.
+		writeBuf = buf
+	}
+
+	c := newConn(netConn, true, u.ReadBufferSize, u.WriteBufferSize, u.WriteBufferPool, br, writeBuf)
+	c.subprotocol = subprotocol
+
+	if compress {
+		c.newCompressionWriter = compressNoContextTakeover
+		c.newDecompressionReader = decompressNoContextTakeover
+	}
+
+	// Use larger of hijacked buffer and connection write buffer for header.
+	p := buf
+	if len(c.writeBuf) > len(p) {
+		p = c.writeBuf
+	}
+	p = p[: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)...)
+	p = append(p, "\r\n"...)
+	if c.subprotocol != "" {
+		p = append(p, "Sec-WebSocket-Protocol: "...)
+		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
+		}
+		for _, v := range vs {
+			p = append(p, k...)
+			p = append(p, ": "...)
+			for i := 0; i < len(v); i++ {
+				b := v[i]
+				if b <= 31 {
+					// prevent response splitting.
+					b = ' '
+				}
+				p = append(p, b)
+			}
+			p = append(p, "\r\n"...)
+		}
+	}
+	p = append(p, "\r\n"...)
+
+	// Clear deadlines set by HTTP server.
+	netConn.SetDeadline(time.Time{})
+
+	if u.HandshakeTimeout > 0 {
+		netConn.SetWriteDeadline(time.Now().Add(u.HandshakeTimeout))
+	}
+	if _, err = netConn.Write(p); err != nil {
+		netConn.Close()
+		return nil, err
+	}
+	if u.HandshakeTimeout > 0 {
+		netConn.SetWriteDeadline(time.Time{})
+	}
+
+	return c, nil
+}
+
+// Upgrade upgrades the HTTP server connection to the WebSocket protocol.
+//
+// Deprecated: Use websocket.Upgrader instead.
+//
+// Upgrade does not perform origin checking. The application is responsible for
+// checking the Origin header before calling Upgrade. An example implementation
+// of the same origin policy check is:
+//
+//	if req.Header.Get("Origin") != "http://"+req.Host {
+//		http.Error(w, "Origin not allowed", http.StatusForbidden)
+//		return
+//	}
+//
+// If the endpoint supports subprotocols, then the application is responsible
+// for negotiating the protocol used on the connection. Use the Subprotocols()
+// function to get the subprotocols requested by the client. Use the
+// Sec-Websocket-Protocol response header to specify the subprotocol selected
+// by the application.
+//
+// The responseHeader is included in the response to the client's upgrade
+// request. Use the responseHeader to specify cookies (Set-Cookie) and the
+// negotiated subprotocol (Sec-Websocket-Protocol).
+//
+// The connection buffers IO to the underlying network connection. The
+// readBufSize and writeBufSize parameters specify the size of the buffers to
+// use. Messages can be larger than the buffers.
+//
+// If the request is not a valid WebSocket handshake, then Upgrade returns an
+// error of type HandshakeError. Applications should handle this error by
+// replying to the client with an HTTP error response.
+func Upgrade(w http.ResponseWriter, r *http.Request, responseHeader http.Header, readBufSize, writeBufSize int) (*Conn, error) {
+	u := Upgrader{ReadBufferSize: readBufSize, WriteBufferSize: writeBufSize}
+	u.Error = func(w http.ResponseWriter, r *http.Request, status int, reason error) {
+		// don't return errors to maintain backwards compatibility
+	}
+	u.CheckOrigin = func(r *http.Request) bool {
+		// allow all connections by default
+		return true
+	}
+	return u.Upgrade(w, r, responseHeader)
+}
+
+// Subprotocols returns the subprotocols requested by the client in the
+// Sec-Websocket-Protocol header.
+func Subprotocols(r *http.Request) []string {
+	h := strings.TrimSpace(r.Header.Get("Sec-Websocket-Protocol"))
+	if h == "" {
+		return nil
+	}
+	protocols := strings.Split(h, ",")
+	for i := range protocols {
+		protocols[i] = strings.TrimSpace(protocols[i])
+	}
+	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")
+}
+
+// bufioReaderSize size returns the size of a bufio.Reader.
+func bufioReaderSize(originalReader io.Reader, br *bufio.Reader) int {
+	// This code assumes that peek on a reset reader returns
+	// bufio.Reader.buf[:0].
+	// TODO: Use bufio.Reader.Size() after Go 1.10
+	br.Reset(originalReader)
+	if p, err := br.Peek(0); err == nil {
+		return cap(p)
+	}
+	return 0
+}
+
+// writeHook is an io.Writer that records the last slice passed to it vio
+// io.Writer.Write.
+type writeHook struct {
+	p []byte
+}
+
+func (wh *writeHook) Write(p []byte) (int, error) {
+	wh.p = p
+	return len(p), nil
+}
+
+// bufioWriterBuffer grabs the buffer from a bufio.Writer.
+func bufioWriterBuffer(originalWriter io.Writer, bw *bufio.Writer) []byte {
+	// This code assumes that bufio.Writer.buf[:1] is passed to the
+	// bufio.Writer's underlying writer.
+	var wh writeHook
+	bw.Reset(&wh)
+	bw.WriteByte(0)
+	bw.Flush()
+
+	bw.Reset(originalWriter)
+
+	return wh.p[:cap(wh.p)]
+}

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

@@ -0,0 +1,19 @@
+// +build go1.8
+
+package websocket
+
+import (
+	"crypto/tls"
+	"net/http/httptrace"
+)
+
+func doHandshakeWithTrace(trace *httptrace.ClientTrace, tlsConn *tls.Conn, cfg *tls.Config) error {
+	if trace.TLSHandshakeStart != nil {
+		trace.TLSHandshakeStart()
+	}
+	err := doHandshake(tlsConn, cfg)
+	if trace.TLSHandshakeDone != nil {
+		trace.TLSHandshakeDone(tlsConn.ConnectionState(), err)
+	}
+	return err
+}

vendor/github.com/gorilla/websocket/trace_17.go

@@ -0,0 +1,12 @@
+// +build !go1.8
+
+package websocket
+
+import (
+	"crypto/tls"
+	"net/http/httptrace"
+)
+
+func doHandshakeWithTrace(trace *httptrace.ClientTrace, tlsConn *tls.Conn, cfg *tls.Config) error {
+	return doHandshake(tlsConn, cfg)
+}

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

@@ -0,0 +1,283 @@
+// Copyright 2013 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 (
+	"crypto/rand"
+	"crypto/sha1"
+	"encoding/base64"
+	"io"
+	"net/http"
+	"strings"
+	"unicode/utf8"
+)
+
+var keyGUID = []byte("258EAFA5-E914-47DA-95CA-C5AB0DC85B11")
+
+func computeAcceptKey(challengeKey string) string {
+	h := sha1.New()
+	h.Write([]byte(challengeKey))
+	h.Write(keyGUID)
+	return base64.StdEncoding.EncodeToString(h.Sum(nil))
+}
+
+func generateChallengeKey() (string, error) {
+	p := make([]byte, 16)
+	if _, err := io.ReadFull(rand.Reader, p); err != nil {
+		return "", err
+	}
+	return base64.StdEncoding.EncodeToString(p), nil
+}
+
+// Token octets per RFC 2616.
+var isTokenOctet = [256]bool{
+	'!':  true,
+	'#':  true,
+	'$':  true,
+	'%':  true,
+	'&':  true,
+	'\'': true,
+	'*':  true,
+	'+':  true,
+	'-':  true,
+	'.':  true,
+	'0':  true,
+	'1':  true,
+	'2':  true,
+	'3':  true,
+	'4':  true,
+	'5':  true,
+	'6':  true,
+	'7':  true,
+	'8':  true,
+	'9':  true,
+	'A':  true,
+	'B':  true,
+	'C':  true,
+	'D':  true,
+	'E':  true,
+	'F':  true,
+	'G':  true,
+	'H':  true,
+	'I':  true,
+	'J':  true,
+	'K':  true,
+	'L':  true,
+	'M':  true,
+	'N':  true,
+	'O':  true,
+	'P':  true,
+	'Q':  true,
+	'R':  true,
+	'S':  true,
+	'T':  true,
+	'U':  true,
+	'W':  true,
+	'V':  true,
+	'X':  true,
+	'Y':  true,
+	'Z':  true,
+	'^':  true,
+	'_':  true,
+	'`':  true,
+	'a':  true,
+	'b':  true,
+	'c':  true,
+	'd':  true,
+	'e':  true,
+	'f':  true,
+	'g':  true,
+	'h':  true,
+	'i':  true,
+	'j':  true,
+	'k':  true,
+	'l':  true,
+	'm':  true,
+	'n':  true,
+	'o':  true,
+	'p':  true,
+	'q':  true,
+	'r':  true,
+	's':  true,
+	't':  true,
+	'u':  true,
+	'v':  true,
+	'w':  true,
+	'x':  true,
+	'y':  true,
+	'z':  true,
+	'|':  true,
+	'~':  true,
+}
+
+// skipSpace returns a slice of the string s with all leading RFC 2616 linear
+// whitespace removed.
+func skipSpace(s string) (rest string) {
+	i := 0
+	for ; i < len(s); i++ {
+		if b := s[i]; b != ' ' && b != '\t' {
+			break
+		}
+	}
+	return s[i:]
+}
+
+// nextToken returns the leading RFC 2616 token of s and the string following
+// the token.
+func nextToken(s string) (token, rest string) {
+	i := 0
+	for ; i < len(s); i++ {
+		if !isTokenOctet[s[i]] {
+			break
+		}
+	}
+	return s[:i], s[i:]
+}
+
+// nextTokenOrQuoted returns the leading token or quoted string per RFC 2616
+// and the string following the token or quoted string.
+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++
+				case b == '\\':
+					escape = true
+				case b == '"':
+					return string(p[:j]), s[i+1:]
+				default:
+					p[j] = b
+					j++
+				}
+			}
+			return "", ""
+		}
+	}
+	return "", ""
+}
+
+// equalASCIIFold returns true if s is equal to t with ASCII case folding as
+// defined in RFC 4790.
+func equalASCIIFold(s, t string) bool {
+	for s != "" && t != "" {
+		sr, size := utf8.DecodeRuneInString(s)
+		s = s[size:]
+		tr, size := utf8.DecodeRuneInString(t)
+		t = t[size:]
+		if sr == tr {
+			continue
+		}
+		if 'A' <= sr && sr <= 'Z' {
+			sr = sr + 'a' - 'A'
+		}
+		if 'A' <= tr && tr <= 'Z' {
+			tr = tr + 'a' - 'A'
+		}
+		if sr != tr {
+			return false
+		}
+	}
+	return s == t
+}
+
+// tokenListContainsValue returns true if the 1#token header with the given
+// name contains a token equal to value with ASCII case folding.
+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 equalASCIIFold(t, value) {
+				return true
+			}
+			if s == "" {
+				continue headers
+			}
+			s = s[1:]
+		}
+	}
+	return false
+}
+
+// parseExtensions 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/github.com/gorilla/websocket/x_net_proxy.go

@@ -0,0 +1,473 @@
+// Code generated by golang.org/x/tools/cmd/bundle. DO NOT EDIT.
+//go:generate bundle -o x_net_proxy.go golang.org/x/net/proxy
+
+// Package proxy provides support for a variety of protocols to proxy network
+// data.
+//
+
+package websocket
+
+import (
+	"errors"
+	"io"
+	"net"
+	"net/url"
+	"os"
+	"strconv"
+	"strings"
+	"sync"
+)
+
+type proxy_direct struct{}
+
+// Direct is a direct proxy: one that makes network connections directly.
+var proxy_Direct = proxy_direct{}
+
+func (proxy_direct) Dial(network, addr string) (net.Conn, error) {
+	return net.Dial(network, addr)
+}
+
+// A PerHost directs connections to a default Dialer unless the host name
+// requested matches one of a number of exceptions.
+type proxy_PerHost struct {
+	def, bypass proxy_Dialer
+
+	bypassNetworks []*net.IPNet
+	bypassIPs      []net.IP
+	bypassZones    []string
+	bypassHosts    []string
+}
+
+// NewPerHost returns a PerHost Dialer that directs connections to either
+// defaultDialer or bypass, depending on whether the connection matches one of
+// the configured rules.
+func proxy_NewPerHost(defaultDialer, bypass proxy_Dialer) *proxy_PerHost {
+	return &proxy_PerHost{
+		def:    defaultDialer,
+		bypass: bypass,
+	}
+}
+
+// Dial connects to the address addr on the given network through either
+// defaultDialer or bypass.
+func (p *proxy_PerHost) Dial(network, addr string) (c net.Conn, err error) {
+	host, _, err := net.SplitHostPort(addr)
+	if err != nil {
+		return nil, err
+	}
+
+	return p.dialerForRequest(host).Dial(network, addr)
+}
+
+func (p *proxy_PerHost) dialerForRequest(host string) proxy_Dialer {
+	if ip := net.ParseIP(host); ip != nil {
+		for _, net := range p.bypassNetworks {
+			if net.Contains(ip) {
+				return p.bypass
+			}
+		}
+		for _, bypassIP := range p.bypassIPs {
+			if bypassIP.Equal(ip) {
+				return p.bypass
+			}
+		}
+		return p.def
+	}
+
+	for _, zone := range p.bypassZones {
+		if strings.HasSuffix(host, zone) {
+			return p.bypass
+		}
+		if host == zone[1:] {
+			// For a zone ".example.com", we match "example.com"
+			// too.
+			return p.bypass
+		}
+	}
+	for _, bypassHost := range p.bypassHosts {
+		if bypassHost == host {
+			return p.bypass
+		}
+	}
+	return p.def
+}
+
+// AddFromString parses a string that contains comma-separated values
+// specifying hosts that should use the bypass proxy. Each value is either an
+// IP address, a CIDR range, a zone (*.example.com) or a host name
+// (localhost). A best effort is made to parse the string and errors are
+// ignored.
+func (p *proxy_PerHost) AddFromString(s string) {
+	hosts := strings.Split(s, ",")
+	for _, host := range hosts {
+		host = strings.TrimSpace(host)
+		if len(host) == 0 {
+			continue
+		}
+		if strings.Contains(host, "/") {
+			// We assume that it's a CIDR address like 127.0.0.0/8
+			if _, net, err := net.ParseCIDR(host); err == nil {
+				p.AddNetwork(net)
+			}
+			continue
+		}
+		if ip := net.ParseIP(host); ip != nil {
+			p.AddIP(ip)
+			continue
+		}
+		if strings.HasPrefix(host, "*.") {
+			p.AddZone(host[1:])
+			continue
+		}
+		p.AddHost(host)
+	}
+}
+
+// AddIP specifies an IP address that will use the bypass proxy. Note that
+// this will only take effect if a literal IP address is dialed. A connection
+// to a named host will never match an IP.
+func (p *proxy_PerHost) AddIP(ip net.IP) {
+	p.bypassIPs = append(p.bypassIPs, ip)
+}
+
+// AddNetwork specifies an IP range that will use the bypass proxy. Note that
+// this will only take effect if a literal IP address is dialed. A connection
+// to a named host will never match.
+func (p *proxy_PerHost) AddNetwork(net *net.IPNet) {
+	p.bypassNetworks = append(p.bypassNetworks, net)
+}
+
+// AddZone specifies a DNS suffix that will use the bypass proxy. A zone of
+// "example.com" matches "example.com" and all of its subdomains.
+func (p *proxy_PerHost) AddZone(zone string) {
+	if strings.HasSuffix(zone, ".") {
+		zone = zone[:len(zone)-1]
+	}
+	if !strings.HasPrefix(zone, ".") {
+		zone = "." + zone
+	}
+	p.bypassZones = append(p.bypassZones, zone)
+}
+
+// AddHost specifies a host name that will use the bypass proxy.
+func (p *proxy_PerHost) AddHost(host string) {
+	if strings.HasSuffix(host, ".") {
+		host = host[:len(host)-1]
+	}
+	p.bypassHosts = append(p.bypassHosts, host)
+}
+
+// A Dialer is a means to establish a connection.
+type proxy_Dialer interface {
+	// Dial connects to the given address via the proxy.
+	Dial(network, addr string) (c net.Conn, err error)
+}
+
+// Auth contains authentication parameters that specific Dialers may require.
+type proxy_Auth struct {
+	User, Password string
+}
+
+// FromEnvironment returns the dialer specified by the proxy related variables in
+// the environment.
+func proxy_FromEnvironment() proxy_Dialer {
+	allProxy := proxy_allProxyEnv.Get()
+	if len(allProxy) == 0 {
+		return proxy_Direct
+	}
+
+	proxyURL, err := url.Parse(allProxy)
+	if err != nil {
+		return proxy_Direct
+	}
+	proxy, err := proxy_FromURL(proxyURL, proxy_Direct)
+	if err != nil {
+		return proxy_Direct
+	}
+
+	noProxy := proxy_noProxyEnv.Get()
+	if len(noProxy) == 0 {
+		return proxy
+	}
+
+	perHost := proxy_NewPerHost(proxy, proxy_Direct)
+	perHost.AddFromString(noProxy)
+	return perHost
+}
+
+// proxySchemes is a map from URL schemes to a function that creates a Dialer
+// from a URL with such a scheme.
+var proxy_proxySchemes map[string]func(*url.URL, proxy_Dialer) (proxy_Dialer, error)
+
+// RegisterDialerType takes a URL scheme and a function to generate Dialers from
+// a URL with that scheme and a forwarding Dialer. Registered schemes are used
+// by FromURL.
+func proxy_RegisterDialerType(scheme string, f func(*url.URL, proxy_Dialer) (proxy_Dialer, error)) {
+	if proxy_proxySchemes == nil {
+		proxy_proxySchemes = make(map[string]func(*url.URL, proxy_Dialer) (proxy_Dialer, error))
+	}
+	proxy_proxySchemes[scheme] = f
+}
+
+// FromURL returns a Dialer given a URL specification and an underlying
+// Dialer for it to make network requests.
+func proxy_FromURL(u *url.URL, forward proxy_Dialer) (proxy_Dialer, error) {
+	var auth *proxy_Auth
+	if u.User != nil {
+		auth = new(proxy_Auth)
+		auth.User = u.User.Username()
+		if p, ok := u.User.Password(); ok {
+			auth.Password = p
+		}
+	}
+
+	switch u.Scheme {
+	case "socks5":
+		return proxy_SOCKS5("tcp", u.Host, auth, forward)
+	}
+
+	// If the scheme doesn't match any of the built-in schemes, see if it
+	// was registered by another package.
+	if proxy_proxySchemes != nil {
+		if f, ok := proxy_proxySchemes[u.Scheme]; ok {
+			return f(u, forward)
+		}
+	}
+
+	return nil, errors.New("proxy: unknown scheme: " + u.Scheme)
+}
+
+var (
+	proxy_allProxyEnv = &proxy_envOnce{
+		names: []string{"ALL_PROXY", "all_proxy"},
+	}
+	proxy_noProxyEnv = &proxy_envOnce{
+		names: []string{"NO_PROXY", "no_proxy"},
+	}
+)
+
+// envOnce looks up an environment variable (optionally by multiple
+// names) once. It mitigates expensive lookups on some platforms
+// (e.g. Windows).
+// (Borrowed from net/http/transport.go)
+type proxy_envOnce struct {
+	names []string
+	once  sync.Once
+	val   string
+}
+
+func (e *proxy_envOnce) Get() string {
+	e.once.Do(e.init)
+	return e.val
+}
+
+func (e *proxy_envOnce) init() {
+	for _, n := range e.names {
+		e.val = os.Getenv(n)
+		if e.val != "" {
+			return
+		}
+	}
+}
+
+// SOCKS5 returns a Dialer that makes SOCKSv5 connections to the given address
+// with an optional username and password. See RFC 1928 and RFC 1929.
+func proxy_SOCKS5(network, addr string, auth *proxy_Auth, forward proxy_Dialer) (proxy_Dialer, error) {
+	s := &proxy_socks5{
+		network: network,
+		addr:    addr,
+		forward: forward,
+	}
+	if auth != nil {
+		s.user = auth.User
+		s.password = auth.Password
+	}
+
+	return s, nil
+}
+
+type proxy_socks5 struct {
+	user, password string
+	network, addr  string
+	forward        proxy_Dialer
+}
+
+const proxy_socks5Version = 5
+
+const (
+	proxy_socks5AuthNone     = 0
+	proxy_socks5AuthPassword = 2
+)
+
+const proxy_socks5Connect = 1
+
+const (
+	proxy_socks5IP4    = 1
+	proxy_socks5Domain = 3
+	proxy_socks5IP6    = 4
+)
+
+var proxy_socks5Errors = []string{
+	"",
+	"general failure",
+	"connection forbidden",
+	"network unreachable",
+	"host unreachable",
+	"connection refused",
+	"TTL expired",
+	"command not supported",
+	"address type not supported",
+}
+
+// Dial connects to the address addr on the given network via the SOCKS5 proxy.
+func (s *proxy_socks5) Dial(network, addr string) (net.Conn, error) {
+	switch network {
+	case "tcp", "tcp6", "tcp4":
+	default:
+		return nil, errors.New("proxy: no support for SOCKS5 proxy connections of type " + network)
+	}
+
+	conn, err := s.forward.Dial(s.network, s.addr)
+	if err != nil {
+		return nil, err
+	}
+	if err := s.connect(conn, addr); err != nil {
+		conn.Close()
+		return nil, err
+	}
+	return conn, nil
+}
+
+// connect takes an existing connection to a socks5 proxy server,
+// and commands the server to extend that connection to target,
+// which must be a canonical address with a host and port.
+func (s *proxy_socks5) connect(conn net.Conn, target string) error {
+	host, portStr, err := net.SplitHostPort(target)
+	if err != nil {
+		return err
+	}
+
+	port, err := strconv.Atoi(portStr)
+	if err != nil {
+		return errors.New("proxy: failed to parse port number: " + portStr)
+	}
+	if port < 1 || port > 0xffff {
+		return errors.New("proxy: port number out of range: " + portStr)
+	}
+
+	// the size here is just an estimate
+	buf := make([]byte, 0, 6+len(host))
+
+	buf = append(buf, proxy_socks5Version)
+	if len(s.user) > 0 && len(s.user) < 256 && len(s.password) < 256 {
+		buf = append(buf, 2 /* num auth methods */, proxy_socks5AuthNone, proxy_socks5AuthPassword)
+	} else {
+		buf = append(buf, 1 /* num auth methods */, proxy_socks5AuthNone)
+	}
+
+	if _, err := conn.Write(buf); err != nil {
+		return errors.New("proxy: failed to write greeting to SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	if _, err := io.ReadFull(conn, buf[:2]); err != nil {
+		return errors.New("proxy: failed to read greeting from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+	if buf[0] != 5 {
+		return errors.New("proxy: SOCKS5 proxy at " + s.addr + " has unexpected version " + strconv.Itoa(int(buf[0])))
+	}
+	if buf[1] == 0xff {
+		return errors.New("proxy: SOCKS5 proxy at " + s.addr + " requires authentication")
+	}
+
+	// See RFC 1929
+	if buf[1] == proxy_socks5AuthPassword {
+		buf = buf[:0]
+		buf = append(buf, 1 /* password protocol version */)
+		buf = append(buf, uint8(len(s.user)))
+		buf = append(buf, s.user...)
+		buf = append(buf, uint8(len(s.password)))
+		buf = append(buf, s.password...)
+
+		if _, err := conn.Write(buf); err != nil {
+			return errors.New("proxy: failed to write authentication request to SOCKS5 proxy at " + s.addr + ": " + err.Error())
+		}
+
+		if _, err := io.ReadFull(conn, buf[:2]); err != nil {
+			return errors.New("proxy: failed to read authentication reply from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+		}
+
+		if buf[1] != 0 {
+			return errors.New("proxy: SOCKS5 proxy at " + s.addr + " rejected username/password")
+		}
+	}
+
+	buf = buf[:0]
+	buf = append(buf, proxy_socks5Version, proxy_socks5Connect, 0 /* reserved */)
+
+	if ip := net.ParseIP(host); ip != nil {
+		if ip4 := ip.To4(); ip4 != nil {
+			buf = append(buf, proxy_socks5IP4)
+			ip = ip4
+		} else {
+			buf = append(buf, proxy_socks5IP6)
+		}
+		buf = append(buf, ip...)
+	} else {
+		if len(host) > 255 {
+			return errors.New("proxy: destination host name too long: " + host)
+		}
+		buf = append(buf, proxy_socks5Domain)
+		buf = append(buf, byte(len(host)))
+		buf = append(buf, host...)
+	}
+	buf = append(buf, byte(port>>8), byte(port))
+
+	if _, err := conn.Write(buf); err != nil {
+		return errors.New("proxy: failed to write connect request to SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	if _, err := io.ReadFull(conn, buf[:4]); err != nil {
+		return errors.New("proxy: failed to read connect reply from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	failure := "unknown error"
+	if int(buf[1]) < len(proxy_socks5Errors) {
+		failure = proxy_socks5Errors[buf[1]]
+	}
+
+	if len(failure) > 0 {
+		return errors.New("proxy: SOCKS5 proxy at " + s.addr + " failed to connect: " + failure)
+	}
+
+	bytesToDiscard := 0
+	switch buf[3] {
+	case proxy_socks5IP4:
+		bytesToDiscard = net.IPv4len
+	case proxy_socks5IP6:
+		bytesToDiscard = net.IPv6len
+	case proxy_socks5Domain:
+		_, err := io.ReadFull(conn, buf[:1])
+		if err != nil {
+			return errors.New("proxy: failed to read domain length from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+		}
+		bytesToDiscard = int(buf[0])
+	default:
+		return errors.New("proxy: got unknown address type " + strconv.Itoa(int(buf[3])) + " from SOCKS5 proxy at " + s.addr)
+	}
+
+	if cap(buf) < bytesToDiscard {
+		buf = make([]byte, bytesToDiscard)
+	} else {
+		buf = buf[:bytesToDiscard]
+	}
+	if _, err := io.ReadFull(conn, buf); err != nil {
+		return errors.New("proxy: failed to read address from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	// Also need to discard the port number
+	if _, err := io.ReadFull(conn, buf[:2]); err != nil {
+		return errors.New("proxy: failed to read port from SOCKS5 proxy at " + s.addr + ": " + err.Error())
+	}
+
+	return nil
+}

vendor/vendor.json

@@ -152,6 +152,12 @@
 			"revision": "553a641470496b2327abcac10b36396bd98e45c9",
 			"revisionTime": "2017-02-15T23:32:05Z"
 		},
+		{
+			"checksumSHA1": "hoilQzrHNOxF5Tc6ctXNTDpv4ck=",
+			"path": "github.com/gorilla/websocket",
+			"revision": "ae1634f6a98965ded3b8789c626cb4e0bd78c3de",
+			"revisionTime": "2019-06-29T18:55:28Z"
+		},
 		{
 			"checksumSHA1": "d9PxF1XQGLMJZRct2R8qVM/eYlE=",
 			"path": "github.com/hashicorp/golang-lru",
@@ -667,8 +673,8 @@
 		{
 			"checksumSHA1": "F+tqxPGFt5x7DKZakbbMmENX1oQ=",
 			"path": "golang.org/x/net/websocket",
-			"revision": "eb5bcb51f2a31c7d5141d810b70815c05d9c9146",
+			"revision": "da137c7871d730100384dbcf36e6f8fa493aef5b",
-			"revisionTime": "2019-04-03T01:06:53Z"
+			"revisionTime": "2019-06-28T18:40:41Z"
 		},
 		{
 			"checksumSHA1": "4TEYFKrAUuwBMqExjQBsnf/CgjQ=",