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http2.go
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http2.go
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package gost
import (
"bufio"
"crypto/tls"
"encoding/base64"
"errors"
"io"
"net"
"net/http"
"net/http/httputil"
"net/url"
"strings"
"sync"
"time"
"github.com/go-log/log"
"golang.org/x/net/http2"
)
type http2Connector struct {
User *url.Userinfo
}
// HTTP2Connector creates a Connector for HTTP2 proxy client.
// It accepts an optional auth info for HTTP Basic Authentication.
func HTTP2Connector(user *url.Userinfo) Connector {
return &http2Connector{User: user}
}
func (c *http2Connector) Connect(conn net.Conn, addr string) (net.Conn, error) {
cc, ok := conn.(*http2ClientConn)
if !ok {
return nil, errors.New("wrong connection type")
}
pr, pw := io.Pipe()
req := &http.Request{
Method: http.MethodConnect,
URL: &url.URL{Scheme: "https", Host: cc.addr},
Header: make(http.Header),
Proto: "HTTP/2.0",
ProtoMajor: 2,
ProtoMinor: 0,
Body: pr,
Host: cc.addr,
ContentLength: -1,
}
req.Header.Set("Gost-Target", addr)
if c.User != nil {
u := c.User.Username()
p, _ := c.User.Password()
req.Header.Set("Proxy-Authorization",
"Basic "+base64.StdEncoding.EncodeToString([]byte(u+":"+p)))
}
if Debug {
dump, _ := httputil.DumpRequest(req, false)
log.Log("[http2]", string(dump))
}
resp, err := cc.client.Do(req)
if err != nil {
return nil, err
}
if Debug {
dump, _ := httputil.DumpResponse(resp, false)
log.Log("[http2]", string(dump))
}
if resp.StatusCode != http.StatusOK {
resp.Body.Close()
return nil, errors.New(resp.Status)
}
hc := &http2Conn{
r: resp.Body,
w: pw,
closed: make(chan struct{}),
}
hc.remoteAddr, _ = net.ResolveTCPAddr("tcp", addr)
hc.localAddr, _ = net.ResolveTCPAddr("tcp", cc.addr)
return hc, nil
}
type http2Transporter struct {
clients map[string]*http.Client
clientMutex sync.Mutex
tlsConfig *tls.Config
}
// HTTP2Transporter creates a Transporter that is used by HTTP2 h2 proxy client.
func HTTP2Transporter(config *tls.Config) Transporter {
if config == nil {
config = &tls.Config{InsecureSkipVerify: true}
}
return &http2Transporter{
clients: make(map[string]*http.Client),
tlsConfig: config,
}
}
func (tr *http2Transporter) Dial(addr string, options ...DialOption) (net.Conn, error) {
opts := &DialOptions{}
for _, option := range options {
option(opts)
}
tr.clientMutex.Lock()
client, ok := tr.clients[addr]
if !ok {
transport := http2.Transport{
TLSClientConfig: tr.tlsConfig,
DialTLS: func(network, adr string, cfg *tls.Config) (net.Conn, error) {
conn, err := opts.Chain.Dial(adr)
if err != nil {
return nil, err
}
return wrapTLSClient(conn, cfg)
},
}
client = &http.Client{
Transport: &transport,
Timeout: opts.Timeout,
}
tr.clients[addr] = client
}
tr.clientMutex.Unlock()
return &http2ClientConn{
addr: addr,
client: client,
}, nil
}
func (tr *http2Transporter) Handshake(conn net.Conn, options ...HandshakeOption) (net.Conn, error) {
return conn, nil
}
func (tr *http2Transporter) Multiplex() bool {
return true
}
type h2Transporter struct {
clients map[string]*http.Client
clientMutex sync.Mutex
tlsConfig *tls.Config
}
// H2Transporter creates a Transporter that is used by HTTP2 h2 tunnel client.
func H2Transporter(config *tls.Config) Transporter {
if config == nil {
config = &tls.Config{InsecureSkipVerify: true}
}
return &h2Transporter{
clients: make(map[string]*http.Client),
tlsConfig: config,
}
}
// H2CTransporter creates a Transporter that is used by HTTP2 h2c tunnel client.
func H2CTransporter() Transporter {
return &h2Transporter{
clients: make(map[string]*http.Client),
}
}
func (tr *h2Transporter) Dial(addr string, options ...DialOption) (net.Conn, error) {
opts := &DialOptions{}
for _, option := range options {
option(opts)
}
tr.clientMutex.Lock()
client, ok := tr.clients[addr]
if !ok {
transport := http2.Transport{
TLSClientConfig: tr.tlsConfig,
DialTLS: func(network, addr string, cfg *tls.Config) (net.Conn, error) {
conn, err := opts.Chain.Dial(addr)
if err != nil {
return nil, err
}
if tr.tlsConfig == nil {
return conn, nil
}
return wrapTLSClient(conn, cfg)
},
}
client = &http.Client{
Transport: &transport,
Timeout: opts.Timeout,
}
tr.clients[addr] = client
}
tr.clientMutex.Unlock()
pr, pw := io.Pipe()
req := &http.Request{
Method: http.MethodConnect,
URL: &url.URL{Scheme: "https", Host: addr},
Header: make(http.Header),
Proto: "HTTP/2.0",
ProtoMajor: 2,
ProtoMinor: 0,
Body: pr,
Host: addr,
ContentLength: -1,
}
if Debug {
dump, _ := httputil.DumpRequest(req, false)
log.Log("[http2]", string(dump))
}
resp, err := client.Do(req)
if err != nil {
return nil, err
}
if Debug {
dump, _ := httputil.DumpResponse(resp, false)
log.Log("[http2]", string(dump))
}
if resp.StatusCode != http.StatusOK {
resp.Body.Close()
return nil, errors.New(resp.Status)
}
conn := &http2Conn{
r: resp.Body,
w: pw,
closed: make(chan struct{}),
}
conn.remoteAddr, _ = net.ResolveTCPAddr("tcp", addr)
conn.localAddr = &net.TCPAddr{IP: net.IPv4zero, Port: 0}
return conn, nil
}
func (tr *h2Transporter) Handshake(conn net.Conn, options ...HandshakeOption) (net.Conn, error) {
opts := &HandshakeOptions{}
for _, option := range options {
option(opts)
}
return conn, nil
}
func (tr *h2Transporter) Multiplex() bool {
return true
}
type http2Handler struct {
options *HandlerOptions
}
// HTTP2Handler creates a server Handler for HTTP2 proxy server.
func HTTP2Handler(opts ...HandlerOption) Handler {
h := &http2Handler{
options: new(HandlerOptions),
}
for _, opt := range opts {
opt(h.options)
}
return h
}
func (h *http2Handler) Handle(conn net.Conn) {
defer conn.Close()
h2c, ok := conn.(*http2ServerConn)
if !ok {
log.Log("[http2] wrong connection type")
return
}
h.roundTrip(h2c.w, h2c.r)
}
func (h *http2Handler) roundTrip(w http.ResponseWriter, r *http.Request) {
target := r.Header.Get("Gost-Target")
if target == "" {
target = r.Host
}
if !strings.Contains(target, ":") {
target += ":80"
}
if Debug {
log.Logf("[http2] %s %s - %s %s", r.Method, r.RemoteAddr, target, r.Proto)
dump, _ := httputil.DumpRequest(r, false)
log.Log("[http2]", string(dump))
}
w.Header().Set("Proxy-Agent", "gost/"+Version)
if !Can("tcp", target, h.options.Whitelist, h.options.Blacklist) {
log.Logf("[http2] Unauthorized to tcp connect to %s", target)
w.WriteHeader(http.StatusForbidden)
return
}
if h.options.Bypass.Contains(target) {
log.Logf("[http2] [bypass] %s", target)
w.WriteHeader(http.StatusForbidden)
return
}
u, p, _ := basicProxyAuth(r.Header.Get("Proxy-Authorization"))
if Debug && (u != "" || p != "") {
log.Logf("[http] %s - %s : Authorization: '%s' '%s'", r.RemoteAddr, target, u, p)
}
if !authenticate(u, p, h.options.Users...) {
log.Logf("[http2] %s <- %s : proxy authentication required", r.RemoteAddr, target)
w.Header().Set("Proxy-Authenticate", "Basic realm=\"gost\"")
w.WriteHeader(http.StatusProxyAuthRequired)
return
}
r.Header.Del("Proxy-Authorization")
r.Header.Del("Proxy-Connection")
cc, err := h.options.Chain.Dial(target)
if err != nil {
log.Logf("[http2] %s -> %s : %s", r.RemoteAddr, target, err)
w.WriteHeader(http.StatusServiceUnavailable)
return
}
defer cc.Close()
if r.Method == http.MethodConnect {
w.WriteHeader(http.StatusOK)
if fw, ok := w.(http.Flusher); ok {
fw.Flush()
}
// compatible with HTTP1.x
if hj, ok := w.(http.Hijacker); ok && r.ProtoMajor == 1 {
// we take over the underly connection
conn, _, err := hj.Hijack()
if err != nil {
log.Logf("[http2] %s -> %s : %s", r.RemoteAddr, target, err)
w.WriteHeader(http.StatusInternalServerError)
return
}
defer conn.Close()
log.Logf("[http2] %s <-> %s : downgrade to HTTP/1.1", r.RemoteAddr, target)
transport(conn, cc)
log.Logf("[http2] %s >-< %s", r.RemoteAddr, target)
return
}
log.Logf("[http2] %s <-> %s", r.RemoteAddr, target)
errc := make(chan error, 2)
go func() {
_, err := io.Copy(cc, r.Body)
errc <- err
}()
go func() {
_, err := io.Copy(flushWriter{w}, cc)
errc <- err
}()
select {
case <-errc:
// glog.V(LWARNING).Infoln("exit", err)
}
log.Logf("[http2] %s >-< %s", r.RemoteAddr, target)
return
}
log.Logf("[http2] %s <-> %s", r.RemoteAddr, target)
if err = r.Write(cc); err != nil {
log.Logf("[http2] %s -> %s : %s", r.RemoteAddr, target, err)
return
}
resp, err := http.ReadResponse(bufio.NewReader(cc), r)
if err != nil {
log.Logf("[http2] %s -> %s : %s", r.RemoteAddr, target, err)
return
}
defer resp.Body.Close()
for k, v := range resp.Header {
for _, vv := range v {
w.Header().Add(k, vv)
}
}
w.WriteHeader(resp.StatusCode)
if _, err := io.Copy(flushWriter{w}, resp.Body); err != nil {
log.Logf("[http2] %s <- %s : %s", r.RemoteAddr, target, err)
}
log.Logf("[http2] %s >-< %s", r.RemoteAddr, target)
}
type http2Listener struct {
server *http.Server
connChan chan *http2ServerConn
errChan chan error
}
// HTTP2Listener creates a Listener for HTTP2 proxy server.
func HTTP2Listener(addr string, config *tls.Config) (Listener, error) {
l := &http2Listener{
connChan: make(chan *http2ServerConn, 1024),
errChan: make(chan error, 1),
}
if config == nil {
config = DefaultTLSConfig
}
server := &http.Server{
Addr: addr,
Handler: http.HandlerFunc(l.handleFunc),
TLSConfig: config,
}
if err := http2.ConfigureServer(server, nil); err != nil {
return nil, err
}
l.server = server
ln, err := tls.Listen("tcp", addr, config)
if err != nil {
return nil, err
}
go func() {
err := server.Serve(ln)
if err != nil {
log.Log("[http2]", err)
}
}()
return l, nil
}
func (l *http2Listener) handleFunc(w http.ResponseWriter, r *http.Request) {
conn := &http2ServerConn{
r: r,
w: w,
closed: make(chan struct{}),
}
select {
case l.connChan <- conn:
default:
log.Logf("[http2] %s - %s: connection queue is full", r.RemoteAddr, l.server.Addr)
return
}
<-conn.closed
}
func (l *http2Listener) Accept() (conn net.Conn, err error) {
select {
case conn = <-l.connChan:
case err = <-l.errChan:
if err == nil {
err = errors.New("accpet on closed listener")
}
}
return
}
func (l *http2Listener) Addr() net.Addr {
addr, _ := net.ResolveTCPAddr("tcp", l.server.Addr)
return addr
}
func (l *http2Listener) Close() (err error) {
select {
case <-l.errChan:
default:
err = l.server.Close()
l.errChan <- err
close(l.errChan)
}
return nil
}
type h2Listener struct {
net.Listener
server *http2.Server
tlsConfig *tls.Config
connChan chan net.Conn
errChan chan error
}
// H2Listener creates a Listener for HTTP2 h2 tunnel server.
func H2Listener(addr string, config *tls.Config) (Listener, error) {
ln, err := net.Listen("tcp", addr)
if err != nil {
return nil, err
}
if config == nil {
config = DefaultTLSConfig
}
l := &h2Listener{
Listener: tcpKeepAliveListener{ln.(*net.TCPListener)},
server: &http2.Server{
// MaxConcurrentStreams: 1000,
PermitProhibitedCipherSuites: true,
IdleTimeout: 5 * time.Minute,
},
tlsConfig: config,
connChan: make(chan net.Conn, 1024),
errChan: make(chan error, 1),
}
go l.listenLoop()
return l, nil
}
// H2CListener creates a Listener for HTTP2 h2c tunnel server.
func H2CListener(addr string) (Listener, error) {
ln, err := net.Listen("tcp", addr)
if err != nil {
return nil, err
}
l := &h2Listener{
Listener: tcpKeepAliveListener{ln.(*net.TCPListener)},
server: &http2.Server{
// MaxConcurrentStreams: 1000,
},
connChan: make(chan net.Conn, 1024),
errChan: make(chan error, 1),
}
go l.listenLoop()
return l, nil
}
func (l *h2Listener) listenLoop() {
for {
conn, err := l.Listener.Accept()
if err != nil {
log.Log("[http2] accept:", err)
l.errChan <- err
close(l.errChan)
return
}
go l.handleLoop(conn)
}
}
func (l *h2Listener) handleLoop(conn net.Conn) {
if l.tlsConfig != nil {
conn = tls.Server(conn, l.tlsConfig)
}
if tc, ok := conn.(*tls.Conn); ok {
// NOTE: HTTP2 server will check the TLS version,
// so we must ensure that the TLS connection is handshake completed.
if err := tc.Handshake(); err != nil {
log.Logf("[http2] %s - %s : %s", conn.RemoteAddr(), conn.LocalAddr(), err)
return
}
}
opt := http2.ServeConnOpts{
Handler: http.HandlerFunc(l.handleFunc),
}
l.server.ServeConn(conn, &opt)
}
func (l *h2Listener) handleFunc(w http.ResponseWriter, r *http.Request) {
log.Logf("[http2] %s %s - %s %s", r.Method, r.RemoteAddr, r.Host, r.Proto)
if Debug {
dump, _ := httputil.DumpRequest(r, false)
log.Log("[http2]", string(dump))
}
w.Header().Set("Proxy-Agent", "gost/"+Version)
conn, err := l.upgrade(w, r)
if err != nil {
log.Logf("[http2] %s %s - %s %s", r.Method, r.RemoteAddr, r.Host, r.Proto)
return
}
select {
case l.connChan <- conn:
default:
conn.Close()
log.Logf("[http2] %s - %s: connection queue is full", conn.RemoteAddr(), conn.LocalAddr())
}
<-conn.closed // NOTE: we need to wait for streaming end, or the connection will be closed
}
func (l *h2Listener) upgrade(w http.ResponseWriter, r *http.Request) (*http2Conn, error) {
if r.Method != http.MethodConnect {
w.WriteHeader(http.StatusMethodNotAllowed)
return nil, errors.New("Method not allowed")
}
w.WriteHeader(http.StatusOK)
if fw, ok := w.(http.Flusher); ok {
fw.Flush() // write header to client
}
remoteAddr, _ := net.ResolveTCPAddr("tcp", r.RemoteAddr)
if remoteAddr == nil {
remoteAddr = &net.TCPAddr{
IP: net.IPv4zero,
Port: 0,
}
}
conn := &http2Conn{
r: r.Body,
w: flushWriter{w},
localAddr: l.Listener.Addr(),
remoteAddr: remoteAddr,
closed: make(chan struct{}),
}
return conn, nil
}
func (l *h2Listener) Accept() (conn net.Conn, err error) {
var ok bool
select {
case conn = <-l.connChan:
case err, ok = <-l.errChan:
if !ok {
err = errors.New("accpet on closed listener")
}
}
return
}
// HTTP2 connection, wrapped up just like a net.Conn
type http2Conn struct {
r io.Reader
w io.Writer
remoteAddr net.Addr
localAddr net.Addr
closed chan struct{}
}
func (c *http2Conn) Read(b []byte) (n int, err error) {
return c.r.Read(b)
}
func (c *http2Conn) Write(b []byte) (n int, err error) {
return c.w.Write(b)
}
func (c *http2Conn) Close() (err error) {
select {
case <-c.closed:
return
default:
close(c.closed)
}
if rc, ok := c.r.(io.Closer); ok {
err = rc.Close()
}
if w, ok := c.w.(io.Closer); ok {
err = w.Close()
}
return
}
func (c *http2Conn) LocalAddr() net.Addr {
return c.localAddr
}
func (c *http2Conn) RemoteAddr() net.Addr {
return c.remoteAddr
}
func (c *http2Conn) SetDeadline(t time.Time) error {
return &net.OpError{Op: "set", Net: "http2", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
}
func (c *http2Conn) SetReadDeadline(t time.Time) error {
return &net.OpError{Op: "set", Net: "http2", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
}
func (c *http2Conn) SetWriteDeadline(t time.Time) error {
return &net.OpError{Op: "set", Net: "http2", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
}
// a dummy HTTP2 server conn used by HTTP2 handler
type http2ServerConn struct {
r *http.Request
w http.ResponseWriter
closed chan struct{}
}
func (c *http2ServerConn) Read(b []byte) (n int, err error) {
return 0, &net.OpError{Op: "read", Net: "http2", Source: nil, Addr: nil, Err: errors.New("read not supported")}
}
func (c *http2ServerConn) Write(b []byte) (n int, err error) {
return 0, &net.OpError{Op: "write", Net: "http2", Source: nil, Addr: nil, Err: errors.New("write not supported")}
}
func (c *http2ServerConn) Close() error {
select {
case <-c.closed:
default:
close(c.closed)
}
return nil
}
func (c *http2ServerConn) LocalAddr() net.Addr {
addr, _ := net.ResolveTCPAddr("tcp", c.r.Host)
return addr
}
func (c *http2ServerConn) RemoteAddr() net.Addr {
addr, _ := net.ResolveTCPAddr("tcp", c.r.RemoteAddr)
return addr
}
func (c *http2ServerConn) SetDeadline(t time.Time) error {
return &net.OpError{Op: "set", Net: "http2", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
}
func (c *http2ServerConn) SetReadDeadline(t time.Time) error {
return &net.OpError{Op: "set", Net: "http2", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
}
func (c *http2ServerConn) SetWriteDeadline(t time.Time) error {
return &net.OpError{Op: "set", Net: "http2", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
}
// a dummy HTTP2 client conn used by HTTP2 client connector
type http2ClientConn struct {
addr string
client *http.Client
}
func (c *http2ClientConn) Read(b []byte) (n int, err error) {
return 0, &net.OpError{Op: "read", Net: "http2", Source: nil, Addr: nil, Err: errors.New("read not supported")}
}
func (c *http2ClientConn) Write(b []byte) (n int, err error) {
return 0, &net.OpError{Op: "write", Net: "http2", Source: nil, Addr: nil, Err: errors.New("write not supported")}
}
func (c *http2ClientConn) Close() error {
return nil
}
func (c *http2ClientConn) LocalAddr() net.Addr {
return nil
}
func (c *http2ClientConn) RemoteAddr() net.Addr {
return nil
}
func (c *http2ClientConn) SetDeadline(t time.Time) error {
return &net.OpError{Op: "set", Net: "http2", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
}
func (c *http2ClientConn) SetReadDeadline(t time.Time) error {
return &net.OpError{Op: "set", Net: "http2", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
}
func (c *http2ClientConn) SetWriteDeadline(t time.Time) error {
return &net.OpError{Op: "set", Net: "http2", Source: nil, Addr: nil, Err: errors.New("deadline not supported")}
}
type flushWriter struct {
w io.Writer
}
func (fw flushWriter) Write(p []byte) (n int, err error) {
defer func() {
if r := recover(); r != nil {
if s, ok := r.(string); ok {
err = errors.New(s)
log.Log("[http2]", err)
return
}
err = r.(error)
}
}()
n, err = fw.w.Write(p)
if err != nil {
// log.Log("flush writer:", err)
return
}
if f, ok := fw.w.(http.Flusher); ok {
f.Flush()
}
return
}