Move Linux client & common packages into a public repo.

stunner/stunner_test.go

@@ -0,0 +1,150 @@
+// Copyright (c) 2020 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 stunner
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net"
+	"sort"
+	"testing"
+	"time"
+
+	"gortc.io/stun"
+)
+
+func TestStun(t *testing.T) {
+	conn1, err := net.ListenPacket("udp4", "127.0.0.1:0")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conn1.Close()
+	conn2, err := net.ListenPacket("udp4", "127.0.0.1:0")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conn2.Close()
+	stunServers := []string{
+		conn1.LocalAddr().String(), conn2.LocalAddr().String(),
+	}
+
+	epCh := make(chan string, 16)
+
+	localConn, err := net.ListenPacket("udp4", "127.0.0.1:0")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	s := &Stunner{
+		Send:     localConn.WriteTo,
+		Endpoint: func(ep string) { epCh <- ep },
+		Servers:  stunServers,
+	}
+
+	stun1Err := make(chan error)
+	go func() {
+		stun1Err <- startSTUN(conn1, s.Receive)
+	}()
+	stun2Err := make(chan error)
+	go func() {
+		stun2Err <- startSTUNDrop1(conn2, s.Receive)
+	}()
+
+	errCh := make(chan error)
+	go func() {
+		errCh <- s.Run(context.Background())
+	}()
+
+	var eps []string
+	select {
+	case ep := <-epCh:
+		eps = append(eps, ep)
+	case <-time.After(100 * time.Millisecond):
+		t.Fatal("missing first endpoint response")
+	}
+	select {
+	case ep := <-epCh:
+		eps = append(eps, ep)
+	case <-time.After(500 * time.Millisecond):
+		t.Fatal("missing second endpoint response")
+	}
+	sort.Strings(eps)
+	if want := "1.2.3.4:1234"; eps[0] != want {
+		t.Errorf("eps[0]=%q, want %q", eps[0], want)
+	}
+	if want := "4.5.6.7:4567"; eps[1] != want {
+		t.Errorf("eps[1]=%q, want %q", eps[1], want)
+	}
+
+	if err := <-errCh; err != nil {
+		t.Fatal(err)
+	}
+}
+
+func startSTUNDrop1(conn net.PacketConn, writeTo func([]byte, *net.UDPAddr)) error {
+	if _, _, err := conn.ReadFrom(make([]byte, 1024)); err != nil {
+		return fmt.Errorf("first stun server read failed: %v", err)
+	}
+	req := new(stun.Message)
+	res := new(stun.Message)
+
+	p := make([]byte, 1024)
+	n, addr, err := conn.ReadFrom(p)
+	if err != nil {
+		return err
+	}
+	p = p[:n]
+	if !stun.IsMessage(p) {
+		return errors.New("not a STUN message")
+	}
+	if _, err := req.Write(p); err != nil {
+		return err
+	}
+	mappedAddr := &stun.XORMappedAddress{
+		IP:   net.ParseIP("1.2.3.4"),
+		Port: 1234,
+	}
+	software := stun.NewSoftware("endpointer")
+	err = res.Build(req, stun.BindingSuccess, software, mappedAddr, stun.Fingerprint)
+	if err != nil {
+		return err
+	}
+	writeTo(res.Raw, addr.(*net.UDPAddr))
+	return nil
+}
+
+func startSTUN(conn net.PacketConn, writeTo func([]byte, *net.UDPAddr)) error {
+	req := new(stun.Message)
+	res := new(stun.Message)
+
+	p := make([]byte, 1024)
+	n, addr, err := conn.ReadFrom(p)
+	if err != nil {
+		return err
+	}
+	p = p[:n]
+	if !stun.IsMessage(p) {
+		return errors.New("not a STUN message")
+	}
+	if _, err := req.Write(p); err != nil {
+		return err
+	}
+	mappedAddr := &stun.XORMappedAddress{
+		IP:   net.ParseIP("4.5.6.7"),
+		Port: 4567,
+	}
+	software := stun.NewSoftware("endpointer")
+	err = res.Build(req, stun.BindingSuccess, software, mappedAddr, stun.Fingerprint)
+	if err != nil {
+		return err
+	}
+	writeTo(res.Raw, addr.(*net.UDPAddr))
+	return nil
+}
+
+// TODO: test retry timeout (overwrite the retryDurations)
+// TODO: test canceling context passed to Run
+// TODO: test sending bad packets