enhancing http proxy code

hodu.go

@@ -1,5 +1,6 @@
 package hodu
 
+import "net"
 import "net/http"
 import "net/netip"
 import "os"
@@ -112,3 +113,20 @@ func dump_call_frame_and_exit(log Logger, req *http.Request, err interface{}) {
 	log.Write("", LOG_ERROR, "[%s] %s %s - %v\n%s", req.RemoteAddr, req.Method, req.URL.String(), err, string(buf))
 	os.Exit(99) // fatal error. treat panic() as a fatal runtime error
 }
+
+func svc_addr_to_dst_addr (svc_addr *net.TCPAddr) *net.TCPAddr {
+	var addr net.TCPAddr
+
+	addr = *svc_addr
+	if addr.IP.To4() != nil {
+		if addr.IP.IsUnspecified() {
+			addr.IP = net.IPv4(127, 0, 0, 1) // net.IPv4loopback is not defined. so use net.IPv4()
+		}
+	} else {
+		if addr.IP.IsUnspecified() {
+			addr.IP = net.IPv6loopback // net.IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}
+		}
+	}
+
+	return &addr
+}

server-proxy.go

@@ -1,5 +1,6 @@
 package hodu
 
+import "bufio"
 import "context"
 import "crypto/tls"
 import _ "embed"
@@ -101,9 +102,12 @@ func mutate_proxy_req_headers(req *http.Request, newreq *http.Request, path_pref
 		newhdr.Set("Upgrade", hdr.Get("Upgrade"))
 	}
 
+/*
 	if httpguts.HeaderValuesContainsToken(hdr["Te"], "trailers") {
 		newhdr.Set("Te", "trailers")
 	}
+*/
+
 
 	remote_addr, _, err = net.SplitHostPort(req.RemoteAddr)
 	if err == nil {
@@ -246,19 +250,128 @@ func (pxy *server_proxy_http_main) serve_websocket(w http.ResponseWriter, req *h
 	}).ServeHTTP(w, req)
 }
 
+func (pxy *server_proxy_http_main) get_route(req *http.Request) (*ServerRoute, string, string, string, error) {
+	var conn_id string
+	var route_id string
+	var r *ServerRoute
+	var path_prefix string
+	var err error
+
+	conn_id = req.PathValue("conn_id")
+	route_id = req.PathValue("route_id")
+	if conn_id == "" && route_id == "" {
+		// it's not via  /_http/<<conn-id>>/<<route-id>>.
+		// get ids from the cookie.
+		var id *http.Cookie
+		var ids []string
+
+		id, err = req.Cookie(SERVER_PROXY_ID_COOKIE)
+		if err != nil {
+			return nil, "", "", "", fmt.Errorf("%s cookie not found - %s", SERVER_PROXY_ID_COOKIE, err.Error())
+		}
+
+		ids = strings.Split(id.Value, "-")
+		if (len(ids) != 2) {
+			return nil, "", "", "", fmt.Errorf("invalid proxy id cookie value - %s", id.Value)
+		}
+
+		conn_id = ids[0]
+		route_id = ids[1]
+		path_prefix = ""
+	} else {
+		path_prefix = fmt.Sprintf("%s/%s/%s", pxy.prefix, conn_id, route_id)
+	}
+
+	r, err = pxy.s.FindServerRouteByIdStr(conn_id, route_id)
+	if err != nil {	return nil, "", "", "", err	}
+
+	return r, path_prefix, conn_id, route_id, nil
+}
+
+func (pxy *server_proxy_http_main) get_upgrade_type(hdr http.Header) string {
+	if httpguts.HeaderValuesContainsToken(hdr["Connection"], "Upgrade") { return  hdr.Get("Upgrade") }
+	return ""
+}
+
+func (pxy *server_proxy_http_main) serve_upgraded(w http.ResponseWriter, req *http.Request, proxy_res *http.Response) {
+	var err_chan chan error
+	var req_up_type string
+	var res_up_type string
+	var proxy_res_body io.ReadWriteCloser
+	var rc *http.ResponseController
+	var client_conn net.Conn
+	var buf_rw *bufio.ReadWriter
+	var ok bool
+	var err error
+
+	req_up_type = pxy.get_upgrade_type(req.Header)
+	res_up_type = pxy.get_upgrade_type(proxy_res.Header)
+	if !strings.EqualFold(req_up_type, res_up_type) {
+		// TODO: error
+		return
+	}
+
+	proxy_res_body, ok = proxy_res.Body.(io.ReadWriteCloser)
+	if !ok {
+		//p.getErrorHandler()(w, req, fmt.Errorf("internal error: 101 switching protocols response with non-writable body"))
+		return
+	}
+	defer proxy_res_body.Close()
+
+	rc = http.NewResponseController(w)
+	client_conn, buf_rw, err = rc.Hijack()
+	if errors.Is(err, http.ErrNotSupported) {
+		//p.getErrorHandler()(w, req, fmt.Errorf("can't switch protocols using non-Hijacker ResponseWriter type %T", w))
+		return
+	}
+
+     //if hijack_err != nil {
+          //p.getErrorHandler()(w, req, fmt.Errorf("Hijack failed on protocol switch: %v", hijackErr))
+     //     return
+     //}
+     defer client_conn.Close()
+
+     copy_headers(w.Header(), proxy_res.Header)
+
+     proxy_res.Header = w.Header()
+     proxy_res.Body = nil // so res.Write only writes the headers; we have res.Body in proxy_res_body above
+     err = proxy_res.Write(buf_rw)
+     if err != nil {
+          //p.getErrorHandler()(w, req, fmt.Errorf("response write: %v", err))
+          return
+     }
+     err = buf_rw.Flush()
+     if err != nil {
+          //p.getErrorHandler()(rw, req, fmt.Errorf("response flush: %v", err))
+          return
+     }
+
+     err_chan = make(chan error, 2)
+     go func() {
+		 var err error
+		_, err =  io.Copy(client_conn, proxy_res_body)
+		err_chan <- err
+	 }()
+
+	 go func() {
+		 var err error
+		_, err =  io.Copy(proxy_res_body, client_conn)
+		err_chan <- err
+	 }()
+     <-err_chan
+}
+
 func (pxy *server_proxy_http_main) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 	var s *Server
 	var r *ServerRoute
 	var status_code int
-	var id *http.Cookie
 	var conn_id string
 	var route_id string
 	var path_prefix string
 	var client *http.Client
 	var resp *http.Response
-	var tcp_conn *net.TCPConn
 	var transport *http.Transport
-	var addr net.TCPAddr
+	var addr *net.TCPAddr
 	var proxy_req *http.Request
 	var proxy_url *url.URL
 	var proxy_url_path string
@@ -277,48 +390,19 @@ func (pxy *server_proxy_http_main) ServeHTTP(w http.ResponseWriter, req *http.Re
 	if ctx.Done() != nil {
 	}
 */
-	conn_id = req.PathValue("conn_id")
-	route_id = req.PathValue("route_id")
-	if conn_id == "" && route_id == "" {
-		// it's not via  /_http/<<conn-id>>/<<route-id>>
-		var ids []string
 
-		id, err = req.Cookie(SERVER_PROXY_ID_COOKIE)
+	r, path_prefix, conn_id, route_id, err = pxy.get_route(req)
-		if err != nil {
-			status_code = http.StatusBadRequest; w.WriteHeader(status_code)
-			err = fmt.Errorf("%s cookie not found - %s", SERVER_PROXY_ID_COOKIE, err.Error())
-			goto oops
-		}
-
-		ids = strings.Split(id.Value, "-")
-		if (len(ids) != 2) {
-			status_code = http.StatusBadRequest; w.WriteHeader(status_code)
-			err = fmt.Errorf("invalid proxy id cookie value - %s", id.Value)
-			goto oops
-		}
-
-		conn_id = ids[0]
-		route_id = ids[1]
-		path_prefix = ""
-	} else {
-		path_prefix = fmt.Sprintf("%s/%s/%s", pxy.prefix, conn_id, route_id)
-	}
-
-	r, err = s.FindServerRouteByIdStr(conn_id, route_id)
 	if err != nil {
 		status_code = http.StatusNotFound; w.WriteHeader(status_code)
 		goto oops
 	}
 
-	addr = *r.svc_addr;
+	addr = svc_addr_to_dst_addr(r.svc_addr)
-	if addr.IP.To4() != nil {
-		addr.IP = net.IPv4(127, 0, 0, 1) // net.IPv4loopback is not defined. so use net.IPv4()
-	} else {
-		addr.IP = net.IPv6loopback // net.IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}
-	}
 
-
+/*
-if httpguts.HeaderValuesContainsToken(req.Header["Connection"], "Upgrade") {
+	if httpguts.HeaderValuesContainsToken(req.Header["Connection"], "Upgrade") &&
+	   httpguts.HeaderValuesContainsToken(req.Header["Upgrade"], "websocket") {
+		// websocket upgrade
 		var ws_url string
 
 		if r.svc_option & RouteOption(ROUTE_OPTION_HTTPS) != 0 {
@@ -331,12 +415,14 @@ if httpguts.HeaderValuesContainsToken(req.Header["Connection"], "Upgrade") {
 
 		ws_url = fmt.Sprintf("%s://%s%s", proxy_proto, r.ptc_addr, proxy_url_path)
 
-	pxy.serve_websocket(w, req, ws_url, &addr)
+		pxy.serve_websocket(w, req, ws_url, addr)
-	return
-}
 
+	} else */{
+		var dialer *net.Dialer
+		var conn net.Conn
 
-	tcp_conn, err = net.DialTCP("tcp", nil, &addr) // need to be specific between tcp4 and tcp6? maybe not
+		dialer = &net.Dialer{}
+		conn, err = dialer.DialContext(req.Context(), "tcp", addr.String())
 		if err != nil {
 			status_code = http.StatusBadGateway; w.WriteHeader(status_code)
 			goto oops
@@ -344,7 +430,7 @@ if httpguts.HeaderValuesContainsToken(req.Header["Connection"], "Upgrade") {
 
 		transport = &http.Transport{
 			DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
-			return tcp_conn, nil
+				return conn, nil
 			},
 			TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
 		}
@@ -376,8 +462,7 @@ if httpguts.HeaderValuesContainsToken(req.Header["Connection"], "Upgrade") {
 
 		s.log.Write("", LOG_INFO, "[%s] %s %s -> %+v", req.RemoteAddr, req.Method, req.URL.String(), proxy_url)
 
-// TODO: http.NewRequestWithContext().??
+		proxy_req, err = http.NewRequestWithContext(req.Context(), req.Method, proxy_url.String(), req.Body)
-	proxy_req, err = http.NewRequest(req.Method, proxy_url.String(), req.Body)
 		if err != nil {
 			status_code = http.StatusInternalServerError; w.WriteHeader(status_code)
 			goto oops
@@ -386,7 +471,6 @@ if httpguts.HeaderValuesContainsToken(req.Header["Connection"], "Upgrade") {
 		mutate_proxy_req_headers(req, proxy_req, path_prefix)
 
 	//fmt.Printf ("proxy NEW req [%+v]\n", proxy_req.Header)
-
 		resp, err = client.Do(proxy_req)
 		if err != nil {
 			status_code = http.StatusInternalServerError; w.WriteHeader(status_code)
@@ -398,7 +482,10 @@ if httpguts.HeaderValuesContainsToken(req.Header["Connection"], "Upgrade") {
 			defer resp.Body.Close()
 
 			if resp.StatusCode == http.StatusSwitchingProtocols {
-			// TODO:
+				if httpguts.HeaderValuesContainsToken(req.Header["Connection"], "Upgrade") {
+					pxy.serve_upgraded(w, req, resp)
+					return
+				}
 			}
 
 			hdr = w.Header()
@@ -413,15 +500,16 @@ if httpguts.HeaderValuesContainsToken(req.Header["Connection"], "Upgrade") {
 
 			if path_prefix == "" {
 				hdr.Add("Set-Cookie", fmt.Sprintf("%s=%s-%s; Path=/; HttpOnly", SERVER_PROXY_ID_COOKIE, conn_id, route_id))
+//fmt.Printf("<<<%s=%s-%s; Path=/; HttpOnly>>>\n", SERVER_PROXY_ID_COOKIE, conn_id, route_id)
 			}
 			status_code = resp.StatusCode; w.WriteHeader(status_code)
 
 			// TODO" if prefixed { append prefix removed...
 			io.Copy(w, resp.Body)
 
-
 			// TODO: handle trailers
 		}
+	}
 
 //done:
 	s.log.Write("", LOG_INFO, "[%s] %s %s %d", req.RemoteAddr, req.Method, req.URL.String(), status_code)
@@ -540,7 +628,7 @@ func (pxy *server_proxy_ssh_ws) send_ws_data(ws *websocket.Conn, type_val string
 
 func (pxy *server_proxy_ssh_ws) connect_ssh (ctx context.Context, username string, password string, r *ServerRoute) ( *ssh.Client, *ssh.Session, io.Writer, io.Reader, error) {
 	var cc *ssh.ClientConfig
-	var addr net.TCPAddr
+	var addr *net.TCPAddr
 	var dialer *net.Dialer
 	var conn net.Conn
 	var ssh_conn ssh.Conn
@@ -565,12 +653,7 @@ func (pxy *server_proxy_ssh_ws) connect_ssh (ctx context.Context, username strin
 	//}
 // TODO: timeout...
 
-	addr = *r.svc_addr;
+	addr = svc_addr_to_dst_addr(r.svc_addr);
-	if addr.IP.To4() != nil {
-		addr.IP = net.IPv4(127, 0, 0, 1) // net.IPv4loopback is not defined. so use net.IPv4()
-	} else {
-		addr.IP = net.IPv6loopback // net.IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}
-	}
 
 	dialer = &net.Dialer{}
 	conn, err = dialer.DialContext(ctx, "tcp", addr.String())