diff --git a/client.go b/client.go index 3687b1e..934e28e 100644 --- a/client.go +++ b/client.go @@ -5,10 +5,8 @@ package websocket import ( - "bufio" "bytes" "crypto/tls" - "encoding/base64" "errors" "io" "io/ioutil" @@ -106,7 +104,7 @@ func hostPortNoPort(u *url.URL) (hostPort, hostNoPort string) { return hostPort, hostNoPort } -// DefaultDialer is a dialer with all fields set to the default zero values. +// DefaultDialer is a dialer with all fields set to the default values. var DefaultDialer = &Dialer{ Proxy: http.ProxyFromEnvironment, } @@ -202,36 +200,52 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re req.Header.Set("Sec-Websocket-Extensions", "permessage-deflate; server_no_context_takeover; client_no_context_takeover") } - 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) } + // Get network dial function. netDial := d.NetDial if netDial == nil { netDialer := &net.Dialer{Deadline: deadline} netDial = netDialer.Dial } - netConn, err := netDial("tcp", targetHostPort) + // 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 } @@ -242,42 +256,6 @@ func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Re } }() - 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 := cloneTLSConfig(d.TLSClientConfig) if cfg.ServerName == "" { diff --git a/client_server_test.go b/client_server_test.go index f8f82d0..50063b7 100644 --- a/client_server_test.go +++ b/client_server_test.go @@ -5,11 +5,14 @@ package websocket import ( + "bytes" "crypto/tls" "crypto/x509" "encoding/base64" + "encoding/binary" "io" "io/ioutil" + "net" "net/http" "net/http/cookiejar" "net/http/httptest" @@ -31,9 +34,10 @@ var cstUpgrader = Upgrader{ } var cstDialer = Dialer{ - Subprotocols: []string{"p1", "p2"}, - ReadBufferSize: 1024, - WriteBufferSize: 1024, + Subprotocols: []string{"p1", "p2"}, + ReadBufferSize: 1024, + WriteBufferSize: 1024, + HandshakeTimeout: 30 * time.Second, } type cstHandler struct{ *testing.T } @@ -143,8 +147,9 @@ func TestProxyDial(t *testing.T) { s := newServer(t) defer s.Close() - surl, _ := url.Parse(s.URL) + surl, _ := url.Parse(s.Server.URL) + cstDialer := cstDialer // make local copy for modification on next line. cstDialer.Proxy = http.ProxyURL(surl) connect := false @@ -173,16 +178,16 @@ func TestProxyDial(t *testing.T) { } defer ws.Close() sendRecv(t, ws) - - cstDialer.Proxy = http.ProxyFromEnvironment } func TestProxyAuthorizationDial(t *testing.T) { s := newServer(t) defer s.Close() - surl, _ := url.Parse(s.URL) + surl, _ := url.Parse(s.Server.URL) surl.User = url.UserPassword("username", "password") + + cstDialer := cstDialer // make local copy for modification on next line. cstDialer.Proxy = http.ProxyURL(surl) connect := false @@ -213,8 +218,6 @@ func TestProxyAuthorizationDial(t *testing.T) { } defer ws.Close() sendRecv(t, ws) - - cstDialer.Proxy = http.ProxyFromEnvironment } func TestDial(t *testing.T) { @@ -518,3 +521,82 @@ func TestDialCompression(t *testing.T) { defer ws.Close() sendRecv(t, ws) } + +func TestSocksProxyDial(t *testing.T) { + s := newServer(t) + defer s.Close() + + proxyListener, err := net.Listen("tcp", "127.0.0.1:0") + if err != nil { + t.Fatalf("listen failed: %v", err) + } + defer proxyListener.Close() + go func() { + c1, err := proxyListener.Accept() + if err != nil { + t.Errorf("proxy accept failed: %v", err) + return + } + defer c1.Close() + + c1.SetDeadline(time.Now().Add(30 * time.Second)) + + buf := make([]byte, 32) + if _, err := io.ReadFull(c1, buf[:3]); err != nil { + t.Errorf("read failed: %v", err) + return + } + if want := []byte{5, 1, 0}; !bytes.Equal(want, buf[:len(want)]) { + t.Errorf("read %x, want %x", buf[:len(want)], want) + } + if _, err := c1.Write([]byte{5, 0}); err != nil { + t.Errorf("write failed: %v", err) + return + } + if _, err := io.ReadFull(c1, buf[:10]); err != nil { + t.Errorf("read failed: %v", err) + return + } + if want := []byte{5, 1, 0, 1}; !bytes.Equal(want, buf[:len(want)]) { + t.Errorf("read %x, want %x", buf[:len(want)], want) + return + } + buf[1] = 0 + if _, err := c1.Write(buf[:10]); err != nil { + t.Errorf("write failed: %v", err) + return + } + + ip := net.IP(buf[4:8]) + port := binary.BigEndian.Uint16(buf[8:10]) + + c2, err := net.DialTCP("tcp", nil, &net.TCPAddr{IP: ip, Port: int(port)}) + if err != nil { + t.Errorf("dial failed; %v", err) + return + } + defer c2.Close() + done := make(chan struct{}) + go func() { + io.Copy(c1, c2) + close(done) + }() + io.Copy(c2, c1) + <-done + }() + + purl, err := url.Parse("socks5://" + proxyListener.Addr().String()) + if err != nil { + t.Fatalf("parse failed: %v", err) + } + + cstDialer := cstDialer // make local copy for modification on next line. + cstDialer.Proxy = http.ProxyURL(purl) + + ws, _, err := cstDialer.Dial(s.URL, nil) + if err != nil { + t.Fatalf("Dial: %v", err) + } + defer ws.Close() + sendRecv(t, ws) +} diff --git a/proxy.go b/proxy.go new file mode 100644 index 0000000..102538b --- /dev/null +++ b/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(netowrk, 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, fowardDial: forwardDialer.Dial}, nil + }) +} + +type httpProxyDialer struct { + proxyURL *url.URL + fowardDial 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.fowardDial(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 +} diff --git a/x_net_proxy.go b/x_net_proxy.go new file mode 100644 index 0000000..2e668f6 --- /dev/null +++ b/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 +}