mihomo/transport/vmess/websocket.go
2023-12-06 12:02:50 +08:00

590 lines
15 KiB
Go

package vmess
import (
"bufio"
"bytes"
"context"
"crypto/sha1"
"crypto/tls"
"encoding/base64"
"encoding/binary"
"errors"
"fmt"
"io"
"net"
"net/http"
"net/url"
"strconv"
"strings"
"time"
"github.com/metacubex/mihomo/common/buf"
N "github.com/metacubex/mihomo/common/net"
tlsC "github.com/metacubex/mihomo/component/tls"
"github.com/metacubex/mihomo/log"
"github.com/gobwas/ws"
"github.com/gobwas/ws/wsutil"
"github.com/zhangyunhao116/fastrand"
)
type websocketConn struct {
net.Conn
state ws.State
reader *wsutil.Reader
controlHandler wsutil.FrameHandlerFunc
rawWriter N.ExtendedWriter
}
type websocketWithEarlyDataConn struct {
net.Conn
wsWriter N.ExtendedWriter
underlay net.Conn
closed bool
dialed chan bool
cancel context.CancelFunc
ctx context.Context
config *WebsocketConfig
}
type WebsocketConfig struct {
Host string
Port string
Path string
Headers http.Header
TLS bool
TLSConfig *tls.Config
MaxEarlyData int
EarlyDataHeaderName string
ClientFingerprint string
V2rayHttpUpgrade bool
V2rayHttpUpgradeFastOpen bool
}
// Read implements net.Conn.Read()
// modify from gobwas/ws/wsutil.readData
func (wsc *websocketConn) Read(b []byte) (n int, err error) {
defer func() { // avoid gobwas/ws pbytes.GetLen panic
if value := recover(); value != nil {
err = fmt.Errorf("websocket error: %s", value)
}
}()
var header ws.Header
for {
n, err = wsc.reader.Read(b)
// in gobwas/ws: "The error is io.EOF only if all of message bytes were read."
// but maybe next frame still have data, so drop it
if errors.Is(err, io.EOF) {
err = nil
}
if !errors.Is(err, wsutil.ErrNoFrameAdvance) {
return
}
header, err = wsc.reader.NextFrame()
if err != nil {
return
}
if header.OpCode.IsControl() {
err = wsc.controlHandler(header, wsc.reader)
if err != nil {
return
}
continue
}
if header.OpCode&(ws.OpBinary|ws.OpText) == 0 {
err = wsc.reader.Discard()
if err != nil {
return
}
continue
}
}
}
// Write implements io.Writer.
func (wsc *websocketConn) Write(b []byte) (n int, err error) {
err = wsutil.WriteMessage(wsc.Conn, wsc.state, ws.OpBinary, b)
if err != nil {
return
}
n = len(b)
return
}
func (wsc *websocketConn) WriteBuffer(buffer *buf.Buffer) error {
var payloadBitLength int
dataLen := buffer.Len()
data := buffer.Bytes()
if dataLen < 126 {
payloadBitLength = 1
} else if dataLen < 65536 {
payloadBitLength = 3
} else {
payloadBitLength = 9
}
var headerLen int
headerLen += 1 // FIN / RSV / OPCODE
headerLen += payloadBitLength
if wsc.state.ClientSide() {
headerLen += 4 // MASK KEY
}
header := buffer.ExtendHeader(headerLen)
header[0] = byte(ws.OpBinary) | 0x80
if wsc.state.ClientSide() {
header[1] = 1 << 7
} else {
header[1] = 0
}
if dataLen < 126 {
header[1] |= byte(dataLen)
} else if dataLen < 65536 {
header[1] |= 126
binary.BigEndian.PutUint16(header[2:], uint16(dataLen))
} else {
header[1] |= 127
binary.BigEndian.PutUint64(header[2:], uint64(dataLen))
}
if wsc.state.ClientSide() {
maskKey := fastrand.Uint32()
binary.LittleEndian.PutUint32(header[1+payloadBitLength:], maskKey)
N.MaskWebSocket(maskKey, data)
}
return wsc.rawWriter.WriteBuffer(buffer)
}
func (wsc *websocketConn) FrontHeadroom() int {
return 14
}
func (wsc *websocketConn) Upstream() any {
return wsc.Conn
}
func (wsc *websocketConn) Close() error {
_ = wsc.Conn.SetWriteDeadline(time.Now().Add(time.Second * 5))
_ = wsutil.WriteMessage(wsc.Conn, wsc.state, ws.OpClose, ws.NewCloseFrameBody(ws.StatusNormalClosure, ""))
_ = wsc.Conn.Close()
return nil
}
func (wsedc *websocketWithEarlyDataConn) Dial(earlyData []byte) error {
base64DataBuf := &bytes.Buffer{}
base64EarlyDataEncoder := base64.NewEncoder(base64.RawURLEncoding, base64DataBuf)
earlyDataBuf := bytes.NewBuffer(earlyData)
if _, err := base64EarlyDataEncoder.Write(earlyDataBuf.Next(wsedc.config.MaxEarlyData)); err != nil {
return fmt.Errorf("failed to encode early data: %w", err)
}
if errc := base64EarlyDataEncoder.Close(); errc != nil {
return fmt.Errorf("failed to encode early data tail: %w", errc)
}
var err error
if wsedc.Conn, err = streamWebsocketConn(wsedc.ctx, wsedc.underlay, wsedc.config, base64DataBuf); err != nil {
wsedc.Close()
return fmt.Errorf("failed to dial WebSocket: %w", err)
}
wsedc.dialed <- true
wsedc.wsWriter = N.NewExtendedWriter(wsedc.Conn)
if earlyDataBuf.Len() != 0 {
_, err = wsedc.Conn.Write(earlyDataBuf.Bytes())
}
return err
}
func (wsedc *websocketWithEarlyDataConn) Write(b []byte) (int, error) {
if wsedc.closed {
return 0, io.ErrClosedPipe
}
if wsedc.Conn == nil {
if err := wsedc.Dial(b); err != nil {
return 0, err
}
return len(b), nil
}
return wsedc.Conn.Write(b)
}
func (wsedc *websocketWithEarlyDataConn) WriteBuffer(buffer *buf.Buffer) error {
if wsedc.closed {
return io.ErrClosedPipe
}
if wsedc.Conn == nil {
if err := wsedc.Dial(buffer.Bytes()); err != nil {
return err
}
return nil
}
return wsedc.wsWriter.WriteBuffer(buffer)
}
func (wsedc *websocketWithEarlyDataConn) Read(b []byte) (int, error) {
if wsedc.closed {
return 0, io.ErrClosedPipe
}
if wsedc.Conn == nil {
select {
case <-wsedc.ctx.Done():
return 0, io.ErrUnexpectedEOF
case <-wsedc.dialed:
}
}
return wsedc.Conn.Read(b)
}
func (wsedc *websocketWithEarlyDataConn) Close() error {
wsedc.closed = true
wsedc.cancel()
if wsedc.Conn == nil {
return nil
}
return wsedc.Conn.Close()
}
func (wsedc *websocketWithEarlyDataConn) LocalAddr() net.Addr {
if wsedc.Conn == nil {
return wsedc.underlay.LocalAddr()
}
return wsedc.Conn.LocalAddr()
}
func (wsedc *websocketWithEarlyDataConn) RemoteAddr() net.Addr {
if wsedc.Conn == nil {
return wsedc.underlay.RemoteAddr()
}
return wsedc.Conn.RemoteAddr()
}
func (wsedc *websocketWithEarlyDataConn) SetDeadline(t time.Time) error {
if err := wsedc.SetReadDeadline(t); err != nil {
return err
}
return wsedc.SetWriteDeadline(t)
}
func (wsedc *websocketWithEarlyDataConn) SetReadDeadline(t time.Time) error {
if wsedc.Conn == nil {
return nil
}
return wsedc.Conn.SetReadDeadline(t)
}
func (wsedc *websocketWithEarlyDataConn) SetWriteDeadline(t time.Time) error {
if wsedc.Conn == nil {
return nil
}
return wsedc.Conn.SetWriteDeadline(t)
}
func (wsedc *websocketWithEarlyDataConn) FrontHeadroom() int {
return 14
}
func (wsedc *websocketWithEarlyDataConn) Upstream() any {
return wsedc.underlay
}
//func (wsedc *websocketWithEarlyDataConn) LazyHeadroom() bool {
// return wsedc.Conn == nil
//}
//
//func (wsedc *websocketWithEarlyDataConn) Upstream() any {
// if wsedc.Conn == nil { // ensure return a nil interface not an interface with nil value
// return nil
// }
// return wsedc.Conn
//}
func (wsedc *websocketWithEarlyDataConn) NeedHandshake() bool {
return wsedc.Conn == nil
}
func streamWebsocketWithEarlyDataConn(conn net.Conn, c *WebsocketConfig) (net.Conn, error) {
ctx, cancel := context.WithCancel(context.Background())
conn = &websocketWithEarlyDataConn{
dialed: make(chan bool, 1),
cancel: cancel,
ctx: ctx,
underlay: conn,
config: c,
}
// websocketWithEarlyDataConn can't correct handle Deadline
// it will not apply the already set Deadline after Dial()
// so call N.NewDeadlineConn to add a safe wrapper
return N.NewDeadlineConn(conn), nil
}
func streamWebsocketConn(ctx context.Context, conn net.Conn, c *WebsocketConfig, earlyData *bytes.Buffer) (net.Conn, error) {
u, err := url.Parse(c.Path)
if err != nil {
return nil, fmt.Errorf("parse url %s error: %w", c.Path, err)
}
uri := url.URL{
Scheme: "ws",
Host: net.JoinHostPort(c.Host, c.Port),
Path: u.Path,
RawQuery: u.RawQuery,
}
if c.TLS {
uri.Scheme = "wss"
config := c.TLSConfig
if config == nil { // The config cannot be nil
config = &tls.Config{NextProtos: []string{"http/1.1"}}
}
if config.ServerName == "" && !config.InsecureSkipVerify { // users must set either ServerName or InsecureSkipVerify in the config.
config = config.Clone()
config.ServerName = uri.Host
}
if len(c.ClientFingerprint) != 0 {
if fingerprint, exists := tlsC.GetFingerprint(c.ClientFingerprint); exists {
utlsConn := tlsC.UClient(conn, config, fingerprint)
if err = utlsConn.BuildWebsocketHandshakeState(); err != nil {
return nil, fmt.Errorf("parse url %s error: %w", c.Path, err)
}
conn = utlsConn
}
} else {
conn = tls.Client(conn, config)
}
if tlsConn, ok := conn.(interface {
HandshakeContext(ctx context.Context) error
}); ok {
if err = tlsConn.HandshakeContext(ctx); err != nil {
return nil, err
}
}
}
request := &http.Request{
Method: http.MethodGet,
URL: &uri,
Header: c.Headers.Clone(),
Host: c.Host,
}
request.Header.Set("Connection", "Upgrade")
request.Header.Set("Upgrade", "websocket")
if host := request.Header.Get("Host"); host != "" {
// For client requests, Host optionally overrides the Host
// header to send. If empty, the Request.Write method uses
// the value of URL.Host. Host may contain an international
// domain name.
request.Host = host
}
request.Header.Del("Host")
var secKey string
if !c.V2rayHttpUpgrade {
const nonceKeySize = 16
// NOTE: bts does not escape.
bts := make([]byte, nonceKeySize)
if _, err = fastrand.Read(bts); err != nil {
return nil, fmt.Errorf("rand read error: %w", err)
}
secKey = base64.StdEncoding.EncodeToString(bts)
request.Header.Set("Sec-WebSocket-Version", "13")
request.Header.Set("Sec-WebSocket-Key", secKey)
}
if earlyData != nil {
earlyDataString := earlyData.String()
if c.EarlyDataHeaderName == "" {
uri.Path += earlyDataString
} else {
request.Header.Set(c.EarlyDataHeaderName, earlyDataString)
}
}
if ctx.Done() != nil {
done := N.SetupContextForConn(ctx, conn)
defer done(&err)
}
err = request.Write(conn)
if err != nil {
return nil, err
}
bufferedConn := N.NewBufferedConn(conn)
if c.V2rayHttpUpgrade && c.V2rayHttpUpgradeFastOpen {
return N.NewEarlyConn(bufferedConn, func() error {
response, err := http.ReadResponse(bufferedConn.Reader(), request)
if err != nil {
return err
}
if response.StatusCode != http.StatusSwitchingProtocols ||
!strings.EqualFold(response.Header.Get("Connection"), "upgrade") ||
!strings.EqualFold(response.Header.Get("Upgrade"), "websocket") {
return fmt.Errorf("unexpected status: %s", response.Status)
}
return nil
}), nil
}
response, err := http.ReadResponse(bufferedConn.Reader(), request)
if err != nil {
return nil, err
}
if response.StatusCode != http.StatusSwitchingProtocols ||
!strings.EqualFold(response.Header.Get("Connection"), "upgrade") ||
!strings.EqualFold(response.Header.Get("Upgrade"), "websocket") {
return nil, fmt.Errorf("unexpected status: %s", response.Status)
}
if c.V2rayHttpUpgrade {
return bufferedConn, nil
}
if log.Level() == log.DEBUG { // we might not check this for performance
secAccept := response.Header.Get("Sec-Websocket-Accept")
const acceptSize = 28 // base64.StdEncoding.EncodedLen(sha1.Size)
if lenSecAccept := len(secAccept); lenSecAccept != acceptSize {
return nil, fmt.Errorf("unexpected Sec-Websocket-Accept length: %d", lenSecAccept)
}
if getSecAccept(secKey) != secAccept {
return nil, errors.New("unexpected Sec-Websocket-Accept")
}
}
conn = newWebsocketConn(conn, ws.StateClientSide)
// websocketConn can't correct handle ReadDeadline
// so call N.NewDeadlineConn to add a safe wrapper
return N.NewDeadlineConn(conn), nil
}
func getSecAccept(secKey string) string {
const magic = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
const nonceSize = 24 // base64.StdEncoding.EncodedLen(nonceKeySize)
p := make([]byte, nonceSize+len(magic))
copy(p[:nonceSize], secKey)
copy(p[nonceSize:], magic)
sum := sha1.Sum(p)
return base64.StdEncoding.EncodeToString(sum[:])
}
func StreamWebsocketConn(ctx context.Context, conn net.Conn, c *WebsocketConfig) (net.Conn, error) {
if u, err := url.Parse(c.Path); err == nil {
if q := u.Query(); q.Get("ed") != "" {
if ed, err := strconv.Atoi(q.Get("ed")); err == nil {
c.MaxEarlyData = ed
c.EarlyDataHeaderName = "Sec-WebSocket-Protocol"
q.Del("ed")
u.RawQuery = q.Encode()
c.Path = u.String()
}
}
}
if c.MaxEarlyData > 0 {
return streamWebsocketWithEarlyDataConn(conn, c)
}
return streamWebsocketConn(ctx, conn, c, nil)
}
func newWebsocketConn(conn net.Conn, state ws.State) *websocketConn {
controlHandler := wsutil.ControlFrameHandler(conn, state)
return &websocketConn{
Conn: conn,
state: state,
reader: &wsutil.Reader{
Source: conn,
State: state,
SkipHeaderCheck: true,
CheckUTF8: false,
OnIntermediate: controlHandler,
},
controlHandler: controlHandler,
rawWriter: N.NewExtendedWriter(conn),
}
}
var replacer = strings.NewReplacer("+", "-", "/", "_", "=", "")
func decodeEd(s string) ([]byte, error) {
return base64.RawURLEncoding.DecodeString(replacer.Replace(s))
}
func decodeXray0rtt(requestHeader http.Header) []byte {
// read inHeader's `Sec-WebSocket-Protocol` for Xray's 0rtt ws
if secProtocol := requestHeader.Get("Sec-WebSocket-Protocol"); len(secProtocol) > 0 {
if edBuf, err := decodeEd(secProtocol); err == nil { // sure could base64 decode
return edBuf
}
}
return nil
}
func IsWebSocketUpgrade(r *http.Request) bool {
return r.Header.Get("Upgrade") == "websocket"
}
func IsV2rayHttpUpdate(r *http.Request) bool {
return IsWebSocketUpgrade(r) && r.Header.Get("Sec-WebSocket-Key") == ""
}
func StreamUpgradedWebsocketConn(w http.ResponseWriter, r *http.Request) (net.Conn, error) {
var conn net.Conn
var rw *bufio.ReadWriter
var err error
isRaw := IsV2rayHttpUpdate(r)
w.Header().Set("Connection", "upgrade")
w.Header().Set("Upgrade", "websocket")
if !isRaw {
w.Header().Set("Sec-Websocket-Accept", getSecAccept(r.Header.Get("Sec-WebSocket-Key")))
}
w.WriteHeader(http.StatusSwitchingProtocols)
if flusher, isFlusher := w.(interface{ FlushError() error }); isFlusher {
err = flusher.FlushError()
if err != nil {
return nil, fmt.Errorf("flush response: %w", err)
}
}
hijacker, canHijack := w.(http.Hijacker)
if !canHijack {
return nil, errors.New("invalid connection, maybe HTTP/2")
}
conn, rw, err = hijacker.Hijack()
if err != nil {
return nil, fmt.Errorf("hijack failed: %w", err)
}
// rw.Writer was flushed, so we only need warp rw.Reader
conn = N.WarpConnWithBioReader(conn, rw.Reader)
if !isRaw {
conn = newWebsocketConn(conn, ws.StateServerSide)
// websocketConn can't correct handle ReadDeadline
// so call N.NewDeadlineConn to add a safe wrapper
conn = N.NewDeadlineConn(conn)
}
if edBuf := decodeXray0rtt(r.Header); len(edBuf) > 0 {
appendOk := false
if bufConn, ok := conn.(*N.BufferedConn); ok {
appendOk = bufConn.AppendData(edBuf)
}
if !appendOk {
conn = N.NewCachedConn(conn, edBuf)
}
}
return conn, nil
}