fix obfs http client

obfs.go

@@ -5,6 +5,7 @@ package gost
 import (
 	"bufio"
 	"bytes"
+	"errors"
 	"fmt"
 	"io"
 	"net"
@@ -70,6 +71,7 @@ type obfsHTTPConn struct {
 	rbuf           bytes.Buffer
 	wbuf           bytes.Buffer
 	isServer       bool
+	headerDrained  bool
 	handshaked     bool
 	handshakeMutex sync.Mutex
 }
@@ -103,7 +105,7 @@ func (c *obfsHTTPConn) serverHandshake() (err error) {
 	}
 	if Debug {
 		dump, _ := httputil.DumpRequest(r, false)
-		log.Logf("[ohttp] %s -> %s\n%s", c.Conn.RemoteAddr(), c.Conn.LocalAddr(), string(dump))
+		log.Logf("[ohttp] %s -> %s\n%s", c.RemoteAddr(), c.LocalAddr(), string(dump))
 	}
 
 	if r.ContentLength > 0 {
@@ -121,26 +123,31 @@ func (c *obfsHTTPConn) serverHandshake() (err error) {
 	}
 
 	b := bytes.Buffer{}
-	if r.Header.Get("Upgrade") == "websocket" {
-		b.WriteString("HTTP/1.1 101 Switching Protocols\r\n")
-		b.WriteString("Server: nginx/1.10.0\r\n")
-		b.WriteString("Date: " + time.Now().Format(time.RFC1123) + "\r\n")
-		b.WriteString("Connection: Upgrade\r\n")
-		b.WriteString("Upgrade: websocket\r\n")
-		b.WriteString(fmt.Sprintf("Sec-WebSocket-Accept: %s\r\n", computeAcceptKey(r.Header.Get("Sec-WebSocket-Key"))))
-		b.WriteString("\r\n")
-	} else {
-		b.WriteString("HTTP/1.1 200 OK\r\n")
-		b.WriteString("Server: nginx/1.10.0\r\n")
+
+	if r.Method != http.MethodGet || r.Header.Get("Upgrade") != "websocket" {
+		b.WriteString("HTTP/1.1 503 Service Unavailable\r\n")
+		b.WriteString("Content-Length: 0\r\n")
 		b.WriteString("Date: " + time.Now().Format(time.RFC1123) + "\r\n")
-		b.WriteString("Content-Type: application/octet-stream\r\n")
-		b.WriteString("Connection: keep-alive\r\n")
-		b.WriteString("Cache-Control: private, no-cache, no-store, proxy-revalidate, no-transform\r\n")
-		b.WriteString("Pragma: no-cache\r\n")
 		b.WriteString("\r\n")
+
+		if Debug {
+			log.Logf("[ohttp] %s <- %s\n%s", c.RemoteAddr(), c.LocalAddr(), b.String())
+		}
+
+		b.WriteTo(c.Conn)
+		return errors.New("bad request")
 	}
+
+	b.WriteString("HTTP/1.1 101 Switching Protocols\r\n")
+	b.WriteString("Server: nginx/1.10.0\r\n")
+	b.WriteString("Date: " + time.Now().Format(time.RFC1123) + "\r\n")
+	b.WriteString("Connection: Upgrade\r\n")
+	b.WriteString("Upgrade: websocket\r\n")
+	b.WriteString(fmt.Sprintf("Sec-WebSocket-Accept: %s\r\n", computeAcceptKey(r.Header.Get("Sec-WebSocket-Key"))))
+	b.WriteString("\r\n")
+
 	if Debug {
-		log.Logf("[ohttp] %s <- %s\n%s", c.Conn.RemoteAddr(), c.Conn.LocalAddr(), b.String())
+		log.Logf("[ohttp] %s <- %s\n%s", c.RemoteAddr(), c.LocalAddr(), b.String())
 	}
 
 	if c.rbuf.Len() > 0 {
@@ -160,29 +167,20 @@ func (c *obfsHTTPConn) clientHandshake() (err error) {
 		URL:        &url.URL{Scheme: "http", Host: c.host},
 		Header:     make(http.Header),
 	}
-	r.Header.Set("User-Agent", "curl/7.49.1")
+	r.Header.Set("User-Agent", DefaultUserAgent)
 	r.Header.Set("Connection", "Upgrade")
 	r.Header.Set("Upgrade", "websocket")
 	key, _ := generateChallengeKey()
 	r.Header.Set("Sec-WebSocket-Key", key)
 
-	if err = r.Write(c.Conn); err != nil {
+	// cache the request header
+	if err = r.Write(&c.wbuf); err != nil {
 		return
 	}
-	if Debug {
-		dump, _ := httputil.DumpRequest(r, false)
-		log.Logf("[ohttp] %s -> %s\n%s", c.Conn.LocalAddr(), c.Conn.RemoteAddr(), string(dump))
-	}
-	var resp *http.Response
-	resp, err = http.ReadResponse(bufio.NewReader(c.Conn), r)
-	if err != nil {
-		return
-	}
-	defer resp.Body.Close()
 
 	if Debug {
-		dump, _ := httputil.DumpResponse(resp, false)
-		log.Logf("[ohttp] %s <- %s\n%s", c.Conn.LocalAddr(), c.Conn.RemoteAddr(), string(dump))
+		dump, _ := httputil.DumpRequest(r, false)
+		log.Logf("[ohttp] %s -> %s\n%s", c.LocalAddr(), c.RemoteAddr(), string(dump))
 	}
 
 	return nil
@@ -192,17 +190,56 @@ func (c *obfsHTTPConn) Read(b []byte) (n int, err error) {
 	if err = c.Handshake(); err != nil {
 		return
 	}
+
+	if !c.isServer {
+		if err = c.drainHeader(); err != nil {
+			return
+		}
+	}
+
 	if c.rbuf.Len() > 0 {
 		return c.rbuf.Read(b)
 	}
 	return c.Conn.Read(b)
 }
 
+func (c *obfsHTTPConn) drainHeader() (err error) {
+	if c.headerDrained {
+		return
+	}
+	c.headerDrained = true
+
+	br := bufio.NewReader(c.Conn)
+	// drain and discard the response header
+	var line string
+	var buf bytes.Buffer
+	for {
+		line, err = br.ReadString('\n')
+		if err != nil {
+			return
+		}
+		buf.WriteString(line)
+		if line == "\r\n" {
+			break
+		}
+	}
+
+	if Debug {
+		log.Logf("[ohttp] %s <- %s\n%s", c.LocalAddr(), c.RemoteAddr(), buf.String())
+	}
+	// cache the extra data for next read.
+	var b []byte
+	b, err = br.Peek(br.Buffered())
+	if len(b) > 0 {
+		_, err = c.rbuf.Write(b)
+	}
+	return
+}
+
 func (c *obfsHTTPConn) Write(b []byte) (n int, err error) {
 	if err = c.Handshake(); err != nil {
 		return
 	}
-
 	if c.wbuf.Len() > 0 {
 		c.wbuf.Write(b) // append the data to the cached header
 		_, err = c.wbuf.WriteTo(c.Conn)

ss.go

@@ -61,12 +61,12 @@ func (c *shadowConnector) Connect(conn net.Conn, addr string, options ...Connect
 		return nil, err
 	}
 
-	sc := ss.NewConn(conn, cipher)
-	// sc, err := ss.DialWithRawAddrConn(rawaddr, conn, cipher)
-	if _, err := sc.Write(rawaddr); err != nil {
-		return nil, err
+	sc := &shadowConn{
+		Conn: ss.NewConn(conn, cipher),
 	}
-	return &shadowConn{sc}, nil
+	sc.wbuf.Write(rawaddr) // cache the header
+
+	return sc, nil
 }
 
 type shadowHandler struct {
@@ -106,7 +106,7 @@ func (h *shadowHandler) Handle(conn net.Conn) {
 			conn.RemoteAddr(), conn.LocalAddr(), err)
 		return
 	}
-	conn = &shadowConn{ss.NewConn(conn, cipher)}
+	conn = &shadowConn{Conn: ss.NewConn(conn, cipher)}
 
 	conn.SetReadDeadline(time.Now().Add(ReadTimeout))
 	host, err := h.getRequest(conn)
@@ -526,11 +526,19 @@ func (h *shadowUDPdHandler) transportUDP(sc net.Conn, cc net.PacketConn) error {
 // Due to in/out byte length is inconsistent of the shadowsocks.Conn.Write,
 // we wrap around it to make io.Copy happy.
 type shadowConn struct {
+	wbuf bytes.Buffer
 	net.Conn
 }
 
 func (c *shadowConn) Write(b []byte) (n int, err error) {
 	n = len(b) // force byte length consistent
+
+	if c.wbuf.Len() > 0 {
+		c.wbuf.Write(b) // append the data to the cached header
+		_, err = c.Conn.Write(c.wbuf.Bytes())
+		c.wbuf.Reset()
+		return
+	}
 	_, err = c.Conn.Write(b)
 	return
 }