diff options
Diffstat (limited to 'vendor/github.com/gorilla/websocket/client.go')
-rw-r--r-- | vendor/github.com/gorilla/websocket/client.go | 350 |
1 files changed, 350 insertions, 0 deletions
diff --git a/vendor/github.com/gorilla/websocket/client.go b/vendor/github.com/gorilla/websocket/client.go new file mode 100644 index 00000000..a353e185 --- /dev/null +++ b/vendor/github.com/gorilla/websocket/client.go @@ -0,0 +1,350 @@ +// 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" + "bytes" + "crypto/tls" + "encoding/base64" + "errors" + "io" + "io/ioutil" + "net" + "net/http" + "net/url" + "strings" + "time" +) + +// ErrBadHandshake is returned when the server response to opening handshake is +// invalid. +var ErrBadHandshake = errors.New("websocket: bad handshake") + +// 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 + + // Input and output buffer sizes. If the buffer size is zero, then a + // default value of 4096 is used. + ReadBufferSize, WriteBufferSize int + + // Subprotocols specifies the client's requested subprotocols. + Subprotocols []string +} + +var errMalformedURL = errors.New("malformed ws or wss URL") + +// parseURL parses the URL. +// +// This function is a replacement for the standard library url.Parse function. +// In Go 1.4 and earlier, url.Parse loses information from the path. +func parseURL(s string) (*url.URL, error) { + // From the RFC: + // + // ws-URI = "ws:" "//" host [ ":" port ] path [ "?" query ] + // wss-URI = "wss:" "//" host [ ":" port ] path [ "?" query ] + + var u url.URL + switch { + case strings.HasPrefix(s, "ws://"): + u.Scheme = "ws" + s = s[len("ws://"):] + case strings.HasPrefix(s, "wss://"): + u.Scheme = "wss" + s = s[len("wss://"):] + default: + return nil, errMalformedURL + } + + if i := strings.Index(s, "?"); i >= 0 { + u.RawQuery = s[i+1:] + s = s[:i] + } + + if i := strings.Index(s, "/"); i >= 0 { + u.Opaque = s[i:] + s = s[:i] + } else { + u.Opaque = "/" + } + + u.Host = s + + if strings.Contains(u.Host, "@") { + // Don't bother parsing user information because user information is + // not allowed in websocket URIs. + return nil, errMalformedURL + } + + return &u, nil +} + +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 zero 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 := parseURL(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, + } + + // 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-Protocol" && len(d.Subprotocols) > 0): + return nil, nil, errors.New("websocket: duplicate header not allowed: " + k) + default: + req.Header[k] = vs + } + } + + hostPort, hostNoPort := hostPortNoPort(u) + + var proxyURL *url.URL + // Check wether the proxy method has been configured + if d.Proxy != nil { + proxyURL, err = d.Proxy(req) + } + if err != nil { + return nil, nil, err + } + + var targetHostPort string + if proxyURL != nil { + targetHostPort, _ = hostPortNoPort(proxyURL) + } else { + targetHostPort = hostPort + } + + var deadline time.Time + if d.HandshakeTimeout != 0 { + deadline = time.Now().Add(d.HandshakeTimeout) + } + + netDial := d.NetDial + if netDial == nil { + netDialer := &net.Dialer{Deadline: deadline} + netDial = netDialer.Dial + } + + netConn, err := netDial("tcp", targetHostPort) + if err != nil { + return nil, nil, err + } + + defer func() { + if netConn != nil { + netConn.Close() + } + }() + + if err := netConn.SetDeadline(deadline); err != nil { + return nil, nil, err + } + + if proxyURL != nil { + connectHeader := make(http.Header) + if user := 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: hostPort}, + Host: hostPort, + Header: connectHeader, + } + + connectReq.Write(netConn) + + // Read response. + // Okay to use and discard buffered reader here, because + // TLS server will not speak until spoken to. + br := bufio.NewReader(netConn) + resp, err := http.ReadResponse(br, connectReq) + if err != nil { + return nil, nil, err + } + if resp.StatusCode != 200 { + f := strings.SplitN(resp.Status, " ", 2) + return nil, nil, errors.New(f[1]) + } + } + + if u.Scheme == "https" { + cfg := d.TLSClientConfig + if cfg == nil { + cfg = &tls.Config{ServerName: hostNoPort} + } else if cfg.ServerName == "" { + shallowCopy := *cfg + cfg = &shallowCopy + 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) + + if err := req.Write(netConn); err != nil { + return nil, nil, err + } + + resp, err := http.ReadResponse(conn.br, req) + if err != nil { + return nil, nil, err + } + 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 + } + + 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 +} |