net/wsconn: remove homegrown wrapper for turning a websocket.Conn into a net.Conn

The one from the nhooyr/websocket package seems to work equally well.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>

cmd/derper/websocket.go

@@ -6,6 +6,7 @@
 
 import (
 	"bufio"
+	"context"
 	"expvar"
 	"log"
 	"net/http"
@@ -13,7 +14,6 @@
 
 	"nhooyr.io/websocket"
 	"tailscale.com/derp"
-	"tailscale.com/net/wsconn"
 )
 
 var counterWebSocketAccepts = expvar.NewInt("derp_websocket_accepts")
@@ -45,7 +45,7 @@ func addWebSocketSupport(s *derp.Server, base http.Handler) http.Handler {
 			return
 		}
 		counterWebSocketAccepts.Add(1)
-		wc := wsconn.New(c)
+		wc := websocket.NetConn(context.Background(), c, websocket.MessageBinary)
 		brw := bufio.NewReadWriter(bufio.NewReader(wc), bufio.NewWriter(wc))
 		s.Accept(wc, brw, r.RemoteAddr)
 	})

cmd/tailscale/depaware.txt

@@ -31,7 +31,7 @@ tailscale.com/cmd/tailscale dependencies: (generated by github.com/tailscale/dep
         go4.org/unsafe/assume-no-moving-gc                           from go4.org/intern
    W 💣 golang.zx2c4.com/wireguard/windows/tunnel/winipcfg           from tailscale.com/net/interfaces+
         inet.af/netaddr                                              from tailscale.com/cmd/tailscale/cli+
-   L    nhooyr.io/websocket                                          from tailscale.com/derp/derphttp+
+   L    nhooyr.io/websocket                                          from tailscale.com/derp/derphttp
    L    nhooyr.io/websocket/internal/errd                            from nhooyr.io/websocket
    L    nhooyr.io/websocket/internal/xsync                           from nhooyr.io/websocket
         tailscale.com                                                from tailscale.com/version
@@ -62,7 +62,6 @@ tailscale.com/cmd/tailscale dependencies: (generated by github.com/tailscale/dep
         tailscale.com/net/tlsdial                                    from tailscale.com/derp/derphttp
         tailscale.com/net/tsaddr                                     from tailscale.com/net/interfaces+
      💣 tailscale.com/net/tshttpproxy                                from tailscale.com/derp/derphttp+
-   L    tailscale.com/net/wsconn                                     from tailscale.com/derp/derphttp
         tailscale.com/paths                                          from tailscale.com/cmd/tailscale/cli+
         tailscale.com/safesocket                                     from tailscale.com/cmd/tailscale/cli+
         tailscale.com/syncs                                          from tailscale.com/net/interfaces+

cmd/tailscaled/depaware.txt

@@ -231,7 +231,6 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         tailscale.com/net/tsdial                                     from tailscale.com/control/controlclient+
      💣 tailscale.com/net/tshttpproxy                                from tailscale.com/control/controlclient+
         tailscale.com/net/tstun                                      from tailscale.com/net/dns+
-        tailscale.com/net/wsconn                                     from tailscale.com/control/controlhttp+
         tailscale.com/paths                                          from tailscale.com/ipn/ipnlocal+
         tailscale.com/portlist                                       from tailscale.com/ipn/ipnlocal
         tailscale.com/safesocket                                     from tailscale.com/client/tailscale+

control/controlhttp/client_js.go

@@ -13,7 +13,6 @@
 	"nhooyr.io/websocket"
 	"tailscale.com/control/controlbase"
 	"tailscale.com/net/dnscache"
-	"tailscale.com/net/wsconn"
 	"tailscale.com/types/key"
 )
 
@@ -45,7 +44,7 @@ func Dial(ctx context.Context, addr string, machineKey key.MachinePrivate, contr
 	if err != nil {
 		return nil, err
 	}
-	netConn := wsconn.New(wsConn)
+	netConn := websocket.NetConn(context.Background(), wsConn, websocket.MessageBinary)
 	cbConn, err := cont(ctx, netConn)
 	if err != nil {
 		netConn.Close()

control/controlhttp/server.go

@@ -14,7 +14,6 @@
 	"nhooyr.io/websocket"
 	"tailscale.com/control/controlbase"
 	"tailscale.com/net/netutil"
-	"tailscale.com/net/wsconn"
 	"tailscale.com/types/key"
 )
 
@@ -106,7 +105,7 @@ func acceptWebsocket(ctx context.Context, w http.ResponseWriter, r *http.Request
 		return nil, fmt.Errorf("decoding base64 handshake parameter: %v", err)
 	}
 
-	conn := wsconn.New(c)
+	conn := websocket.NetConn(ctx, c, websocket.MessageBinary)
 	nc, err := controlbase.Server(ctx, conn, private, init)
 	if err != nil {
 		conn.Close()

derp/derphttp/websocket.go

@@ -13,7 +13,6 @@
 	"net"
 
 	"nhooyr.io/websocket"
-	"tailscale.com/net/wsconn"
 )
 
 func init() {
@@ -29,5 +28,6 @@ func dialWebsocket(ctx context.Context, urlStr string) (net.Conn, error) {
 		return nil, err
 	}
 	log.Printf("websocket: connected to %v", urlStr)
-	return wsconn.New(c), nil
+	netConn := websocket.NetConn(context.Background(), c, websocket.MessageBinary)
+	return netConn, nil
 }

net/wsconn/wsconn.go

@@ -1,104 +0,0 @@
-// Copyright (c) 2021 Tailscale Inc & 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 wsconn contains an adapter type that turns
-// a websocket connection into a net.Conn.
-package wsconn
-
-import (
-	"context"
-	"net"
-	"sync"
-	"time"
-
-	"nhooyr.io/websocket"
-)
-
-// New returns a net.Conn wrapper around c,
-// using c to send and receive binary messages with
-// chunks of bytes with no defined framing, effectively
-// discarding all WebSocket-level message framing.
-func New(c *websocket.Conn) net.Conn {
-	return &websocketConn{c: c}
-}
-
-// websocketConn implements net.Conn around a *websocket.Conn,
-// treating a websocket.Conn as a byte stream, ignoring the WebSocket
-// frame/message boundaries.
-type websocketConn struct {
-	c *websocket.Conn
-
-	// rextra are extra bytes owned by the reader.
-	rextra []byte
-
-	mu         sync.Mutex
-	rdeadline  time.Time
-	cancelRead context.CancelFunc
-}
-
-func (wc *websocketConn) LocalAddr() net.Addr  { return addr{} }
-func (wc *websocketConn) RemoteAddr() net.Addr { return addr{} }
-
-type addr struct{}
-
-func (addr) Network() string { return "websocket" }
-func (addr) String() string  { return "websocket" }
-
-func (wc *websocketConn) Read(p []byte) (n int, err error) {
-	// Drain any leftover from previously.
-	n = copy(p, wc.rextra)
-	if n > 0 {
-		wc.rextra = wc.rextra[n:]
-		return n, nil
-	}
-
-	var ctx context.Context
-	var cancel context.CancelFunc
-
-	wc.mu.Lock()
-	if dl := wc.rdeadline; !dl.IsZero() {
-		ctx, cancel = context.WithDeadline(context.Background(), wc.rdeadline)
-	} else {
-		ctx, cancel = context.WithDeadline(context.Background(), time.Now().Add(30*24*time.Hour))
-		wc.rdeadline = time.Time{}
-	}
-	wc.cancelRead = cancel
-	wc.mu.Unlock()
-	defer cancel()
-
-	_, buf, err := wc.c.Read(ctx)
-	n = copy(p, buf)
-	wc.rextra = buf[n:]
-	return n, err
-}
-
-func (wc *websocketConn) Write(p []byte) (n int, err error) {
-	err = wc.c.Write(context.Background(), websocket.MessageBinary, p)
-	if err != nil {
-		return 0, err
-	}
-	return len(p), nil
-}
-
-func (wc *websocketConn) Close() error { return wc.c.Close(websocket.StatusNormalClosure, "close") }
-
-func (wc *websocketConn) SetDeadline(t time.Time) error {
-	wc.SetReadDeadline(t)
-	wc.SetWriteDeadline(t)
-	return nil
-}
-
-func (wc *websocketConn) SetReadDeadline(t time.Time) error {
-	wc.mu.Lock()
-	defer wc.mu.Unlock()
-	if !t.IsZero() && (wc.rdeadline.IsZero() || t.Before(wc.rdeadline)) && wc.cancelRead != nil {
-		wc.cancelRead()
-	}
-	wc.rdeadline = t
-	return nil
-}
-
-func (wc *websocketConn) SetWriteDeadline(t time.Time) error {
-	return nil
-}