Fix handshake timeout

[f4nff]

client.go

// 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"
	"crypto/tls"
	"errors"
	"io"
	"io/ioutil"
	"net"
	"net/http"
	"net/url"
	"strings"
	"time"
	"fmt"
)

// 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)

	// 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. 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

	// Subprotocols specifies the client's requested subprotocols.
	Subprotocols []string

	// EnableCompression specifies if the client should attempt to negotiate
	// per message compression (RFC 7692). Setting this value to true does not
	// guarantee that compression will be supported. Currently only "no context
	// takeover" modes are supported.
	EnableCompression bool

	// Jar specifies the cookie jar.
	// If Jar is nil, cookies are not sent in requests and ignored
	// in responses.
	Jar http.CookieJar
}

var errMalformedURL = errors.New("malformed ws or wss URL")

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,
}

// Dial 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).
//
// 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) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Response, error) {

	if d == nil {
		d = &Dialer{
			Proxy: http.ProxyFromEnvironment,
		}
	}

	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
	}

	tmpHost :=  u.Host
	if u.Scheme == "http" && strings.HasSuffix(u.Host,":80") {
		tmpHost = u.Host[:len(u.Host) - 3]
	} else if u.Scheme == "https" && strings.HasSuffix(u.Host,":443") {
		tmpHost = u.Host[:len(u.Host) - 4]
	}

	req := &http.Request{
		Method:     "GET",
		URL:        u,
		Proto:      "HTTP/1.1",
		ProtoMajor: 1,
		ProtoMinor: 1,
		Header:     make(http.Header),
//		Host:       u.Host,
		Host:       tmpHost,
	}

	// 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.Set("Sec-Websocket-Extensions", "permessage-deflate; server_no_context_takeover; client_no_context_takeover")
	}

	var deadline time.Time
	if d.HandshakeTimeout != 0 {
		deadline = time.Now().Add(d.HandshakeTimeout)
	}

	// Get network dial function.
	netDial := d.NetDial
	if netDial == nil {
		netDialer := &net.Dialer{Deadline: deadline}
		netDial = netDialer.Dial
	}

	// If needed, wrap the dial function to set the connection deadline.
	if !deadline.Equal(time.Time{}) {
		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)
	netConn, err := netDial("tcp", hostPort)
	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
		if err := tlsConn.Handshake(); err != nil {
			return nil, nil, err
		}
		if !cfg.InsecureSkipVerify {
			if err := tlsConn.VerifyHostname(cfg.ServerName); err != nil {
				return nil, nil, err
			}
		}
	}

	conn := newConn(netConn, false, d.ReadBufferSize, d.WriteBufferSize)

	// 设置write 写数据超时时间
	netConn.SetReadDeadline(time.Now().Add(time.Duration( 5 * time.Second)))
	netConn.SetWriteDeadline(time.Now().Add(time.Duration( 5 * time.Second)))

	if err := req.Write(netConn); err != nil {
		fmt.Println("***xxx write timeout ", err)
		return nil, nil, err
	}

	// 设置 read timeout 时间
	resp, err := http.ReadResponse(conn.br, req)
	if err != nil {
		fmt.Println("***xxx http.ReadResponse timeout ", err)
		return nil, nil, err
	}

	if resp.StatusCode != 101 {
		// 状态码错误!!!
		fmt.Println("***xxx http.Read status error ", err)
		return nil, nil, errors.New("websocks 状态码错误")
	}

	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{})

	// conn.conn.SetReadDeadline(time.Now().Add(time.Duration( 5 * time.Second)))

	netConn = nil // to avoid close in defer.
	return conn, resp, nil
}

---

After creating a successful TCP connection, the request was successfully sent but no reply timeout was determined.

Describe the problem you are having and steps to reproduce the problem.

The handshake deadline does work per new test. I am closing because there's no response from OP after a month.

[silence44]

Hello. I think I have same problem.

Right now I'm trying to set websocket connection from one golang app to another one using tls.

On client side I do just simple connect:

u := url.URL{Scheme: "wss", Host: "localhost:8000", Path: "/server_client"}
conn, _, err := websocket.DefaultDialer.Dial(u.String(), nil)
log.Info("Tried connect...")

On server side I have gin gonic with TLS:

r := gin.Default()

r.GET("/server_client", func(c *gin.Context) {
	s.wshandler(hub, c.Writer, c.Request)
})

return r.RunTLS(":8000", certFilePath, keyFilePath)

So after connect I see on server side this message "http: TLS handshake error from [::1]:50194: read tcp [::1]:8000->[::1]:50194: read: connection reset by peer"

And the problem that code on client side just stay on dialing forever. I mean that I can't see log "Tried connect...".

[silence44]

I was using my local certificate and fixed issue with custom dialer config where I set:
TLSClientConfig: &tls.Config{InsecureSkipVerify: true}

Anyway without it my code was waiting forever for something I don't understand. I think it still may be an issue for somebody. Please tell me how I can help you to provide more details about my issue.

@silence44 Open a new issue with the information you posted here.

[silence44]

Created in #420