tailscale/derp/derp_test.go

1462 lines
34 KiB
Go

// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause
package derp
import (
"bufio"
"bytes"
"context"
"crypto/x509"
"encoding/asn1"
"encoding/json"
"errors"
"expvar"
"fmt"
"io"
"log"
"net"
"os"
"reflect"
"strconv"
"sync"
"testing"
"time"
"go4.org/mem"
"golang.org/x/time/rate"
"tailscale.com/net/memnet"
"tailscale.com/types/key"
"tailscale.com/types/logger"
)
func TestClientInfoUnmarshal(t *testing.T) {
for i, in := range []string{
`{"Version":5,"MeshKey":"abc"}`,
`{"version":5,"meshKey":"abc"}`,
} {
var got clientInfo
if err := json.Unmarshal([]byte(in), &got); err != nil {
t.Fatalf("[%d]: %v", i, err)
}
want := clientInfo{Version: 5, MeshKey: "abc"}
if got != want {
t.Errorf("[%d]: got %+v; want %+v", i, got, want)
}
}
}
func TestSendRecv(t *testing.T) {
serverPrivateKey := key.NewNode()
s := NewServer(serverPrivateKey, t.Logf)
defer s.Close()
const numClients = 3
var clientPrivateKeys []key.NodePrivate
var clientKeys []key.NodePublic
for i := 0; i < numClients; i++ {
priv := key.NewNode()
clientPrivateKeys = append(clientPrivateKeys, priv)
clientKeys = append(clientKeys, priv.Public())
}
ln, err := net.Listen("tcp", "127.0.0.1:0")
if err != nil {
t.Fatal(err)
}
defer ln.Close()
var clients []*Client
var connsOut []Conn
var recvChs []chan []byte
errCh := make(chan error, 3)
for i := 0; i < numClients; i++ {
t.Logf("Connecting client %d ...", i)
cout, err := net.Dial("tcp", ln.Addr().String())
if err != nil {
t.Fatal(err)
}
defer cout.Close()
connsOut = append(connsOut, cout)
cin, err := ln.Accept()
if err != nil {
t.Fatal(err)
}
defer cin.Close()
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
brwServer := bufio.NewReadWriter(bufio.NewReader(cin), bufio.NewWriter(cin))
go s.Accept(ctx, cin, brwServer, fmt.Sprintf("test-client-%d", i))
key := clientPrivateKeys[i]
brw := bufio.NewReadWriter(bufio.NewReader(cout), bufio.NewWriter(cout))
c, err := NewClient(key, cout, brw, t.Logf)
if err != nil {
t.Fatalf("client %d: %v", i, err)
}
waitConnect(t, c)
clients = append(clients, c)
recvChs = append(recvChs, make(chan []byte))
t.Logf("Connected client %d.", i)
}
var peerGoneCount expvar.Int
t.Logf("Starting read loops")
for i := 0; i < numClients; i++ {
go func(i int) {
for {
m, err := clients[i].Recv()
if err != nil {
errCh <- err
return
}
switch m := m.(type) {
default:
t.Errorf("unexpected message type %T", m)
continue
case PeerGoneMessage:
peerGoneCount.Add(1)
case ReceivedPacket:
if m.Source.IsZero() {
t.Errorf("zero Source address in ReceivedPacket")
}
recvChs[i] <- bytes.Clone(m.Data)
}
}
}(i)
}
recv := func(i int, want string) {
t.Helper()
select {
case b := <-recvChs[i]:
if got := string(b); got != want {
t.Errorf("client1.Recv=%q, want %q", got, want)
}
case <-time.After(5 * time.Second):
t.Errorf("client%d.Recv, got nothing, want %q", i, want)
}
}
recvNothing := func(i int) {
t.Helper()
select {
case b := <-recvChs[0]:
t.Errorf("client%d.Recv=%q, want nothing", i, string(b))
default:
}
}
wantActive := func(total, home int64) {
t.Helper()
dl := time.Now().Add(5 * time.Second)
var gotTotal, gotHome int64
for time.Now().Before(dl) {
gotTotal, gotHome = s.curClients.Value(), s.curHomeClients.Value()
if gotTotal == total && gotHome == home {
return
}
time.Sleep(10 * time.Millisecond)
}
t.Errorf("total/home=%v/%v; want %v/%v", gotTotal, gotHome, total, home)
}
wantClosedPeers := func(want int64) {
t.Helper()
var got int64
dl := time.Now().Add(5 * time.Second)
for time.Now().Before(dl) {
if got = peerGoneCount.Value(); got == want {
return
}
}
t.Errorf("peer gone count = %v; want %v", got, want)
}
msg1 := []byte("hello 0->1\n")
if err := clients[0].Send(clientKeys[1], msg1); err != nil {
t.Fatal(err)
}
recv(1, string(msg1))
recvNothing(0)
recvNothing(2)
msg2 := []byte("hello 1->2\n")
if err := clients[1].Send(clientKeys[2], msg2); err != nil {
t.Fatal(err)
}
recv(2, string(msg2))
recvNothing(0)
recvNothing(1)
wantActive(3, 0)
clients[0].NotePreferred(true)
wantActive(3, 1)
clients[0].NotePreferred(true)
wantActive(3, 1)
clients[0].NotePreferred(false)
wantActive(3, 0)
clients[0].NotePreferred(false)
wantActive(3, 0)
clients[1].NotePreferred(true)
wantActive(3, 1)
connsOut[1].Close()
wantActive(2, 0)
wantClosedPeers(1)
clients[2].NotePreferred(true)
wantActive(2, 1)
clients[2].NotePreferred(false)
wantActive(2, 0)
connsOut[2].Close()
wantActive(1, 0)
wantClosedPeers(1)
t.Logf("passed")
s.Close()
}
func TestSendFreeze(t *testing.T) {
serverPrivateKey := key.NewNode()
s := NewServer(serverPrivateKey, t.Logf)
defer s.Close()
s.WriteTimeout = 100 * time.Millisecond
// We send two streams of messages:
//
// alice --> bob
// alice --> cathy
//
// Then cathy stops processing messages.
// That should not interfere with alice talking to bob.
newClient := func(ctx context.Context, name string, k key.NodePrivate) (c *Client, clientConn memnet.Conn) {
t.Helper()
c1, c2 := memnet.NewConn(name, 1024)
go s.Accept(ctx, c1, bufio.NewReadWriter(bufio.NewReader(c1), bufio.NewWriter(c1)), name)
brw := bufio.NewReadWriter(bufio.NewReader(c2), bufio.NewWriter(c2))
c, err := NewClient(k, c2, brw, t.Logf)
if err != nil {
t.Fatal(err)
}
waitConnect(t, c)
return c, c2
}
ctx, clientCtxCancel := context.WithCancel(context.Background())
defer clientCtxCancel()
aliceKey := key.NewNode()
aliceClient, aliceConn := newClient(ctx, "alice", aliceKey)
bobKey := key.NewNode()
bobClient, bobConn := newClient(ctx, "bob", bobKey)
cathyKey := key.NewNode()
cathyClient, cathyConn := newClient(ctx, "cathy", cathyKey)
var (
aliceCh = make(chan struct{}, 32)
bobCh = make(chan struct{}, 32)
cathyCh = make(chan struct{}, 32)
)
chs := func(name string) chan struct{} {
switch name {
case "alice":
return aliceCh
case "bob":
return bobCh
case "cathy":
return cathyCh
default:
panic("unknown ch: " + name)
}
}
errCh := make(chan error, 4)
recv := func(name string, client *Client) {
ch := chs(name)
for {
m, err := client.Recv()
if err != nil {
errCh <- fmt.Errorf("%s: %w", name, err)
return
}
switch m := m.(type) {
default:
errCh <- fmt.Errorf("%s: unexpected message type %T", name, m)
return
case ReceivedPacket:
if m.Source.IsZero() {
errCh <- fmt.Errorf("%s: zero Source address in ReceivedPacket", name)
return
}
select {
case ch <- struct{}{}:
default:
}
}
}
}
go recv("alice", aliceClient)
go recv("bob", bobClient)
go recv("cathy", cathyClient)
var cancel func()
go func() {
t := time.NewTicker(2 * time.Millisecond)
defer t.Stop()
var ctx context.Context
ctx, cancel = context.WithCancel(context.Background())
for {
select {
case <-t.C:
case <-ctx.Done():
errCh <- nil
return
}
msg1 := []byte("hello alice->bob\n")
if err := aliceClient.Send(bobKey.Public(), msg1); err != nil {
errCh <- fmt.Errorf("alice send to bob: %w", err)
return
}
msg2 := []byte("hello alice->cathy\n")
// TODO: an error is expected here.
// We ignore it, maybe we should log it somehow?
aliceClient.Send(cathyKey.Public(), msg2)
}
}()
drainAny := func(ch chan struct{}) {
// We are draining potentially infinite sources,
// so place some reasonable upper limit.
//
// The important thing here is to make sure that
// if any tokens remain in the channel, they
// must have been generated after drainAny was
// called.
for i := 0; i < cap(ch); i++ {
select {
case <-ch:
default:
return
}
}
}
drain := func(t *testing.T, name string) bool {
t.Helper()
timer := time.NewTimer(1 * time.Second)
defer timer.Stop()
// Ensure ch has at least one element.
ch := chs(name)
select {
case <-ch:
case <-timer.C:
t.Errorf("no packet received by %s", name)
return false
}
// Drain remaining.
drainAny(ch)
return true
}
isEmpty := func(t *testing.T, name string) {
t.Helper()
select {
case <-chs(name):
t.Errorf("packet received by %s, want none", name)
default:
}
}
t.Run("initial send", func(t *testing.T) {
drain(t, "bob")
drain(t, "cathy")
isEmpty(t, "alice")
})
t.Run("block cathy", func(t *testing.T) {
// Block cathy. Now the cathyConn buffer will fill up quickly,
// and the derp server will back up.
cathyConn.SetReadBlock(true)
time.Sleep(2 * s.WriteTimeout)
drain(t, "bob")
drainAny(chs("cathy"))
isEmpty(t, "alice")
// Now wait a little longer, and ensure packets still flow to bob
if !drain(t, "bob") {
t.Errorf("connection alice->bob frozen by alice->cathy")
}
})
// Cleanup, make sure we process all errors.
t.Logf("TEST COMPLETE, cancelling sender")
cancel()
t.Logf("closing connections")
// Close bob before alice.
// Starting with alice can cause a PeerGoneMessage to reach
// bob before bob is closed, causing a test flake (issue 2668).
bobConn.Close()
aliceConn.Close()
cathyConn.Close()
for i := 0; i < cap(errCh); i++ {
err := <-errCh
if err != nil {
if errors.Is(err, io.EOF) || errors.Is(err, net.ErrClosed) {
continue
}
t.Error(err)
}
}
}
type testServer struct {
s *Server
ln net.Listener
logf logger.Logf
mu sync.Mutex
pubName map[key.NodePublic]string
clients map[*testClient]bool
}
func (ts *testServer) addTestClient(c *testClient) {
ts.mu.Lock()
defer ts.mu.Unlock()
ts.clients[c] = true
}
func (ts *testServer) addKeyName(k key.NodePublic, name string) {
ts.mu.Lock()
defer ts.mu.Unlock()
ts.pubName[k] = name
ts.logf("test adding named key %q for %x", name, k)
}
func (ts *testServer) keyName(k key.NodePublic) string {
ts.mu.Lock()
defer ts.mu.Unlock()
if name, ok := ts.pubName[k]; ok {
return name
}
return k.ShortString()
}
func (ts *testServer) close(t *testing.T) error {
ts.ln.Close()
ts.s.Close()
for c := range ts.clients {
c.close(t)
}
return nil
}
func newTestServer(t *testing.T, ctx context.Context) *testServer {
t.Helper()
logf := logger.WithPrefix(t.Logf, "derp-server: ")
s := NewServer(key.NewNode(), logf)
s.SetMeshKey("mesh-key")
ln, err := net.Listen("tcp", "127.0.0.1:0")
if err != nil {
t.Fatal(err)
}
go func() {
i := 0
for {
i++
c, err := ln.Accept()
if err != nil {
return
}
// TODO: register c in ts so Close also closes it?
go func(i int) {
brwServer := bufio.NewReadWriter(bufio.NewReader(c), bufio.NewWriter(c))
go s.Accept(ctx, c, brwServer, fmt.Sprintf("test-client-%d", i))
}(i)
}
}()
return &testServer{
s: s,
ln: ln,
logf: logf,
clients: map[*testClient]bool{},
pubName: map[key.NodePublic]string{},
}
}
type testClient struct {
name string
c *Client
nc net.Conn
pub key.NodePublic
ts *testServer
closed bool
}
func newTestClient(t *testing.T, ts *testServer, name string, newClient func(net.Conn, key.NodePrivate, logger.Logf) (*Client, error)) *testClient {
t.Helper()
nc, err := net.Dial("tcp", ts.ln.Addr().String())
if err != nil {
t.Fatal(err)
}
k := key.NewNode()
ts.addKeyName(k.Public(), name)
c, err := newClient(nc, k, logger.WithPrefix(t.Logf, "client-"+name+": "))
if err != nil {
t.Fatal(err)
}
tc := &testClient{
name: name,
nc: nc,
c: c,
ts: ts,
pub: k.Public(),
}
ts.addTestClient(tc)
return tc
}
func newRegularClient(t *testing.T, ts *testServer, name string) *testClient {
return newTestClient(t, ts, name, func(nc net.Conn, priv key.NodePrivate, logf logger.Logf) (*Client, error) {
brw := bufio.NewReadWriter(bufio.NewReader(nc), bufio.NewWriter(nc))
c, err := NewClient(priv, nc, brw, logf)
if err != nil {
return nil, err
}
waitConnect(t, c)
return c, nil
})
}
func newTestWatcher(t *testing.T, ts *testServer, name string) *testClient {
return newTestClient(t, ts, name, func(nc net.Conn, priv key.NodePrivate, logf logger.Logf) (*Client, error) {
brw := bufio.NewReadWriter(bufio.NewReader(nc), bufio.NewWriter(nc))
c, err := NewClient(priv, nc, brw, logf, MeshKey("mesh-key"))
if err != nil {
return nil, err
}
waitConnect(t, c)
if err := c.WatchConnectionChanges(); err != nil {
return nil, err
}
return c, nil
})
}
func (tc *testClient) wantPresent(t *testing.T, peers ...key.NodePublic) {
t.Helper()
want := map[key.NodePublic]bool{}
for _, k := range peers {
want[k] = true
}
for {
m, err := tc.c.recvTimeout(time.Second)
if err != nil {
t.Fatal(err)
}
switch m := m.(type) {
case PeerPresentMessage:
got := key.NodePublic(m)
if !want[got] {
t.Fatalf("got peer present for %v; want present for %v", tc.ts.keyName(got), logger.ArgWriter(func(bw *bufio.Writer) {
for _, pub := range peers {
fmt.Fprintf(bw, "%s ", tc.ts.keyName(pub))
}
}))
}
delete(want, got)
if len(want) == 0 {
return
}
default:
t.Fatalf("unexpected message type %T", m)
}
}
}
func (tc *testClient) wantGone(t *testing.T, peer key.NodePublic) {
t.Helper()
m, err := tc.c.recvTimeout(time.Second)
if err != nil {
t.Fatal(err)
}
switch m := m.(type) {
case PeerGoneMessage:
got := key.NodePublic(m)
if peer != got {
t.Errorf("got gone message for %v; want gone for %v", tc.ts.keyName(got), tc.ts.keyName(peer))
}
default:
t.Fatalf("unexpected message type %T", m)
}
}
func (c *testClient) close(t *testing.T) {
t.Helper()
if c.closed {
return
}
c.closed = true
t.Logf("closing client %q (%x)", c.name, c.pub)
c.nc.Close()
}
// TestWatch tests the connection watcher mechanism used by regional
// DERP nodes to mesh up with each other.
func TestWatch(t *testing.T) {
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
ts := newTestServer(t, ctx)
defer ts.close(t)
w1 := newTestWatcher(t, ts, "w1")
w1.wantPresent(t, w1.pub)
c1 := newRegularClient(t, ts, "c1")
w1.wantPresent(t, c1.pub)
c2 := newRegularClient(t, ts, "c2")
w1.wantPresent(t, c2.pub)
w2 := newTestWatcher(t, ts, "w2")
w1.wantPresent(t, w2.pub)
w2.wantPresent(t, w1.pub, w2.pub, c1.pub, c2.pub)
c3 := newRegularClient(t, ts, "c3")
w1.wantPresent(t, c3.pub)
w2.wantPresent(t, c3.pub)
c2.close(t)
w1.wantGone(t, c2.pub)
w2.wantGone(t, c2.pub)
w3 := newTestWatcher(t, ts, "w3")
w1.wantPresent(t, w3.pub)
w2.wantPresent(t, w3.pub)
w3.wantPresent(t, c1.pub, c3.pub, w1.pub, w2.pub, w3.pub)
c1.close(t)
w1.wantGone(t, c1.pub)
w2.wantGone(t, c1.pub)
w3.wantGone(t, c1.pub)
}
type testFwd int
func (testFwd) ForwardPacket(key.NodePublic, key.NodePublic, []byte) error {
panic("not called in tests")
}
func pubAll(b byte) (ret key.NodePublic) {
var bs [32]byte
for i := range bs {
bs[i] = b
}
return key.NodePublicFromRaw32(mem.B(bs[:]))
}
func TestForwarderRegistration(t *testing.T) {
s := &Server{
clients: make(map[key.NodePublic]clientSet),
clientsMesh: map[key.NodePublic]PacketForwarder{},
}
want := func(want map[key.NodePublic]PacketForwarder) {
t.Helper()
if got := s.clientsMesh; !reflect.DeepEqual(got, want) {
t.Fatalf("mismatch\n got: %v\nwant: %v\n", got, want)
}
}
wantCounter := func(c *expvar.Int, want int) {
t.Helper()
if got := c.Value(); got != int64(want) {
t.Errorf("counter = %v; want %v", got, want)
}
}
u1 := pubAll(1)
u2 := pubAll(2)
u3 := pubAll(3)
s.AddPacketForwarder(u1, testFwd(1))
s.AddPacketForwarder(u2, testFwd(2))
want(map[key.NodePublic]PacketForwarder{
u1: testFwd(1),
u2: testFwd(2),
})
// Verify a remove of non-registered forwarder is no-op.
s.RemovePacketForwarder(u2, testFwd(999))
want(map[key.NodePublic]PacketForwarder{
u1: testFwd(1),
u2: testFwd(2),
})
// Verify a remove of non-registered user is no-op.
s.RemovePacketForwarder(u3, testFwd(1))
want(map[key.NodePublic]PacketForwarder{
u1: testFwd(1),
u2: testFwd(2),
})
// Actual removal.
s.RemovePacketForwarder(u2, testFwd(2))
want(map[key.NodePublic]PacketForwarder{
u1: testFwd(1),
})
// Adding a dup for a user.
wantCounter(&s.multiForwarderCreated, 0)
s.AddPacketForwarder(u1, testFwd(100))
s.AddPacketForwarder(u1, testFwd(100)) // dup to trigger dup path
want(map[key.NodePublic]PacketForwarder{
u1: newMultiForwarder(testFwd(1), testFwd(100)),
})
wantCounter(&s.multiForwarderCreated, 1)
// Removing a forwarder in a multi set that doesn't exist; does nothing.
s.RemovePacketForwarder(u1, testFwd(55))
want(map[key.NodePublic]PacketForwarder{
u1: newMultiForwarder(testFwd(1), testFwd(100)),
})
// Removing a forwarder in a multi set that does exist should collapse it away
// from being a multiForwarder.
wantCounter(&s.multiForwarderDeleted, 0)
s.RemovePacketForwarder(u1, testFwd(1))
want(map[key.NodePublic]PacketForwarder{
u1: testFwd(100),
})
wantCounter(&s.multiForwarderDeleted, 1)
// Removing an entry for a client that's still connected locally should result
// in a nil forwarder.
u1c := &sclient{
key: u1,
logf: logger.Discard,
}
s.clients[u1] = singleClient{u1c}
s.RemovePacketForwarder(u1, testFwd(100))
want(map[key.NodePublic]PacketForwarder{
u1: nil,
})
// But once that client disconnects, it should go away.
s.unregisterClient(u1c)
want(map[key.NodePublic]PacketForwarder{})
// But if it already has a forwarder, it's not removed.
s.AddPacketForwarder(u1, testFwd(2))
s.unregisterClient(u1c)
want(map[key.NodePublic]PacketForwarder{
u1: testFwd(2),
})
// Now pretend u1 was already connected locally (so clientsMesh[u1] is nil), and then we heard
// that they're also connected to a peer of ours. That shouldn't transition the forwarder
// from nil to the new one, not a multiForwarder.
s.clients[u1] = singleClient{u1c}
s.clientsMesh[u1] = nil
want(map[key.NodePublic]PacketForwarder{
u1: nil,
})
s.AddPacketForwarder(u1, testFwd(3))
want(map[key.NodePublic]PacketForwarder{
u1: testFwd(3),
})
}
type channelFwd struct {
// id is to ensure that different instances that reference the
// same channel are not equal, as they are used as keys in the
// multiForwarder map.
id int
c chan []byte
}
func (f channelFwd) ForwardPacket(_ key.NodePublic, _ key.NodePublic, packet []byte) error {
f.c <- packet
return nil
}
func TestMultiForwarder(t *testing.T) {
received := 0
var wg sync.WaitGroup
ch := make(chan []byte)
ctx, cancel := context.WithCancel(context.Background())
s := &Server{
clients: make(map[key.NodePublic]clientSet),
clientsMesh: map[key.NodePublic]PacketForwarder{},
}
u := pubAll(1)
s.AddPacketForwarder(u, channelFwd{1, ch})
wg.Add(2)
go func() {
defer wg.Done()
for {
select {
case <-ch:
received += 1
case <-ctx.Done():
return
}
}
}()
go func() {
defer wg.Done()
for {
s.AddPacketForwarder(u, channelFwd{2, ch})
s.AddPacketForwarder(u, channelFwd{3, ch})
s.RemovePacketForwarder(u, channelFwd{2, ch})
s.RemovePacketForwarder(u, channelFwd{1, ch})
s.AddPacketForwarder(u, channelFwd{1, ch})
s.RemovePacketForwarder(u, channelFwd{3, ch})
if ctx.Err() != nil {
return
}
}
}()
// Number of messages is chosen arbitrarily, just for this loop to
// run long enough concurrently with {Add,Remove}PacketForwarder loop above.
numMsgs := 5000
var fwd PacketForwarder
for i := 0; i < numMsgs; i++ {
s.mu.Lock()
fwd = s.clientsMesh[u]
s.mu.Unlock()
fwd.ForwardPacket(u, u, []byte(strconv.Itoa(i)))
}
cancel()
wg.Wait()
if received != numMsgs {
t.Errorf("expected %d messages to be forwarded; got %d", numMsgs, received)
}
}
func TestMetaCert(t *testing.T) {
priv := key.NewNode()
pub := priv.Public()
s := NewServer(priv, t.Logf)
certBytes := s.MetaCert()
cert, err := x509.ParseCertificate(certBytes)
if err != nil {
log.Fatal(err)
}
if fmt.Sprint(cert.SerialNumber) != fmt.Sprint(ProtocolVersion) {
t.Errorf("serial = %v; want %v", cert.SerialNumber, ProtocolVersion)
}
if g, w := cert.Subject.CommonName, fmt.Sprintf("derpkey%s", pub.UntypedHexString()); g != w {
t.Errorf("CommonName = %q; want %q", g, w)
}
if n := len(cert.Extensions); n != 1 {
t.Fatalf("got %d extensions; want 1", n)
}
// oidExtensionBasicConstraints is the Basic Constraints ID copied
// from the x509 package.
oidExtensionBasicConstraints := asn1.ObjectIdentifier{2, 5, 29, 19}
if id := cert.Extensions[0].Id; !id.Equal(oidExtensionBasicConstraints) {
t.Errorf("extension ID = %v; want %v", id, oidExtensionBasicConstraints)
}
}
type dummyNetConn struct {
net.Conn
}
func (dummyNetConn) SetReadDeadline(time.Time) error { return nil }
func TestClientRecv(t *testing.T) {
tests := []struct {
name string
input []byte
want any
}{
{
name: "ping",
input: []byte{
byte(framePing), 0, 0, 0, 8,
1, 2, 3, 4, 5, 6, 7, 8,
},
want: PingMessage{1, 2, 3, 4, 5, 6, 7, 8},
},
{
name: "pong",
input: []byte{
byte(framePong), 0, 0, 0, 8,
1, 2, 3, 4, 5, 6, 7, 8,
},
want: PongMessage{1, 2, 3, 4, 5, 6, 7, 8},
},
{
name: "health_bad",
input: []byte{
byte(frameHealth), 0, 0, 0, 3,
byte('B'), byte('A'), byte('D'),
},
want: HealthMessage{Problem: "BAD"},
},
{
name: "health_ok",
input: []byte{
byte(frameHealth), 0, 0, 0, 0,
},
want: HealthMessage{},
},
{
name: "server_restarting",
input: []byte{
byte(frameRestarting), 0, 0, 0, 8,
0, 0, 0, 1,
0, 0, 0, 2,
},
want: ServerRestartingMessage{
ReconnectIn: 1 * time.Millisecond,
TryFor: 2 * time.Millisecond,
},
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
c := &Client{
nc: dummyNetConn{},
br: bufio.NewReader(bytes.NewReader(tt.input)),
logf: t.Logf,
}
got, err := c.Recv()
if err != nil {
t.Fatal(err)
}
if !reflect.DeepEqual(got, tt.want) {
t.Errorf("got %#v; want %#v", got, tt.want)
}
})
}
}
func TestClientSendPing(t *testing.T) {
var buf bytes.Buffer
c := &Client{
bw: bufio.NewWriter(&buf),
}
if err := c.SendPing([8]byte{1, 2, 3, 4, 5, 6, 7, 8}); err != nil {
t.Fatal(err)
}
want := []byte{
byte(framePing), 0, 0, 0, 8,
1, 2, 3, 4, 5, 6, 7, 8,
}
if !bytes.Equal(buf.Bytes(), want) {
t.Errorf("unexpected output\nwrote: % 02x\n want: % 02x", buf.Bytes(), want)
}
}
func TestClientSendPong(t *testing.T) {
var buf bytes.Buffer
c := &Client{
bw: bufio.NewWriter(&buf),
}
if err := c.SendPong([8]byte{1, 2, 3, 4, 5, 6, 7, 8}); err != nil {
t.Fatal(err)
}
want := []byte{
byte(framePong), 0, 0, 0, 8,
1, 2, 3, 4, 5, 6, 7, 8,
}
if !bytes.Equal(buf.Bytes(), want) {
t.Errorf("unexpected output\nwrote: % 02x\n want: % 02x", buf.Bytes(), want)
}
}
func TestServerDupClients(t *testing.T) {
serverPriv := key.NewNode()
var s *Server
clientPriv := key.NewNode()
clientPub := clientPriv.Public()
var c1, c2, c3 *sclient
var clientName map[*sclient]string
// run starts a new test case and resets clients back to their zero values.
run := func(name string, dupPolicy dupPolicy, f func(t *testing.T)) {
s = NewServer(serverPriv, t.Logf)
s.dupPolicy = dupPolicy
c1 = &sclient{key: clientPub, logf: logger.WithPrefix(t.Logf, "c1: ")}
c2 = &sclient{key: clientPub, logf: logger.WithPrefix(t.Logf, "c2: ")}
c3 = &sclient{key: clientPub, logf: logger.WithPrefix(t.Logf, "c3: ")}
clientName = map[*sclient]string{
c1: "c1",
c2: "c2",
c3: "c3",
}
t.Run(name, f)
}
runBothWays := func(name string, f func(t *testing.T)) {
run(name+"_disablefighters", disableFighters, f)
run(name+"_lastwriteractive", lastWriterIsActive, f)
}
wantSingleClient := func(t *testing.T, want *sclient) {
t.Helper()
switch s := s.clients[want.key].(type) {
case singleClient:
if s.c != want {
t.Error("wrong single client")
return
}
if want.isDup.Load() {
t.Errorf("unexpected isDup on singleClient")
}
if want.isDisabled.Load() {
t.Errorf("unexpected isDisabled on singleClient")
}
case nil:
t.Error("no clients for key")
case *dupClientSet:
t.Error("unexpected multiple clients for key")
}
}
wantNoClient := func(t *testing.T) {
t.Helper()
switch s := s.clients[clientPub].(type) {
case nil:
// Good.
return
default:
t.Errorf("got %T; want empty", s)
}
}
wantDupSet := func(t *testing.T) *dupClientSet {
t.Helper()
switch s := s.clients[clientPub].(type) {
case *dupClientSet:
return s
default:
t.Fatalf("wanted dup set; got %T", s)
return nil
}
}
wantActive := func(t *testing.T, want *sclient) {
t.Helper()
set, ok := s.clients[clientPub]
if !ok {
t.Error("no set for key")
return
}
got := set.ActiveClient()
if got != want {
t.Errorf("active client = %q; want %q", clientName[got], clientName[want])
}
}
checkDup := func(t *testing.T, c *sclient, want bool) {
t.Helper()
if got := c.isDup.Load(); got != want {
t.Errorf("client %q isDup = %v; want %v", clientName[c], got, want)
}
}
checkDisabled := func(t *testing.T, c *sclient, want bool) {
t.Helper()
if got := c.isDisabled.Load(); got != want {
t.Errorf("client %q isDisabled = %v; want %v", clientName[c], got, want)
}
}
wantDupConns := func(t *testing.T, want int) {
t.Helper()
if got := s.dupClientConns.Value(); got != int64(want) {
t.Errorf("dupClientConns = %v; want %v", got, want)
}
}
wantDupKeys := func(t *testing.T, want int) {
t.Helper()
if got := s.dupClientKeys.Value(); got != int64(want) {
t.Errorf("dupClientKeys = %v; want %v", got, want)
}
}
// Common case: a single client comes and goes, with no dups.
runBothWays("one_comes_and_goes", func(t *testing.T) {
wantNoClient(t)
s.registerClient(c1)
wantSingleClient(t, c1)
s.unregisterClient(c1)
wantNoClient(t)
})
// A still somewhat common case: a single client was
// connected and then their wifi dies or laptop closes
// or they switch networks and connect from a
// different network. They have two connections but
// it's not very bad. Only their new one is
// active. The last one, being dead, doesn't send and
// thus the new one doesn't get disabled.
runBothWays("small_overlap_replacement", func(t *testing.T) {
wantNoClient(t)
s.registerClient(c1)
wantSingleClient(t, c1)
wantActive(t, c1)
wantDupKeys(t, 0)
wantDupKeys(t, 0)
s.registerClient(c2) // wifi dies; c2 replacement connects
wantDupSet(t)
wantDupConns(t, 2)
wantDupKeys(t, 1)
checkDup(t, c1, true)
checkDup(t, c2, true)
checkDisabled(t, c1, false)
checkDisabled(t, c2, false)
wantActive(t, c2) // sends go to the replacement
s.unregisterClient(c1) // c1 finally times out
wantSingleClient(t, c2)
checkDup(t, c2, false) // c2 is longer a dup
wantActive(t, c2)
wantDupConns(t, 0)
wantDupKeys(t, 0)
})
// Key cloning situation with concurrent clients, both trying
// to write.
run("concurrent_dups_get_disabled", disableFighters, func(t *testing.T) {
wantNoClient(t)
s.registerClient(c1)
wantSingleClient(t, c1)
wantActive(t, c1)
s.registerClient(c2)
wantDupSet(t)
wantDupKeys(t, 1)
wantDupConns(t, 2)
wantActive(t, c2)
checkDup(t, c1, true)
checkDup(t, c2, true)
checkDisabled(t, c1, false)
checkDisabled(t, c2, false)
s.noteClientActivity(c2)
checkDisabled(t, c1, false)
checkDisabled(t, c2, false)
s.noteClientActivity(c1)
checkDisabled(t, c1, true)
checkDisabled(t, c2, true)
wantActive(t, nil)
s.registerClient(c3)
wantActive(t, c3)
checkDisabled(t, c3, false)
wantDupKeys(t, 1)
wantDupConns(t, 3)
s.unregisterClient(c3)
wantActive(t, nil)
wantDupKeys(t, 1)
wantDupConns(t, 2)
s.unregisterClient(c2)
wantSingleClient(t, c1)
wantDupKeys(t, 0)
wantDupConns(t, 0)
})
// Key cloning with an A->B->C->A series instead.
run("concurrent_dups_three_parties", disableFighters, func(t *testing.T) {
wantNoClient(t)
s.registerClient(c1)
s.registerClient(c2)
s.registerClient(c3)
s.noteClientActivity(c1)
checkDisabled(t, c1, true)
checkDisabled(t, c2, true)
checkDisabled(t, c3, true)
wantActive(t, nil)
})
run("activity_promotes_primary_when_nil", disableFighters, func(t *testing.T) {
wantNoClient(t)
// Last registered client is the active one...
s.registerClient(c1)
wantActive(t, c1)
s.registerClient(c2)
wantActive(t, c2)
s.registerClient(c3)
s.noteClientActivity(c2)
wantActive(t, c3)
// But if the last one goes away, the one with the
// most recent activity wins.
s.unregisterClient(c3)
wantActive(t, c2)
})
run("concurrent_dups_three_parties_last_writer", lastWriterIsActive, func(t *testing.T) {
wantNoClient(t)
s.registerClient(c1)
wantActive(t, c1)
s.registerClient(c2)
wantActive(t, c2)
s.noteClientActivity(c1)
checkDisabled(t, c1, false)
checkDisabled(t, c2, false)
wantActive(t, c1)
s.noteClientActivity(c2)
checkDisabled(t, c1, false)
checkDisabled(t, c2, false)
wantActive(t, c2)
s.unregisterClient(c2)
checkDisabled(t, c1, false)
wantActive(t, c1)
})
}
func TestLimiter(t *testing.T) {
rl := rate.NewLimiter(rate.Every(time.Minute), 100)
for i := 0; i < 200; i++ {
r := rl.Reserve()
d := r.Delay()
t.Logf("i=%d, allow=%v, d=%v", i, r.OK(), d)
}
}
func BenchmarkSendRecv(b *testing.B) {
for _, size := range []int{10, 100, 1000, 10000} {
b.Run(fmt.Sprintf("msgsize=%d", size), func(b *testing.B) { benchmarkSendRecvSize(b, size) })
}
}
func benchmarkSendRecvSize(b *testing.B, packetSize int) {
serverPrivateKey := key.NewNode()
s := NewServer(serverPrivateKey, logger.Discard)
defer s.Close()
k := key.NewNode()
clientKey := k.Public()
ln, err := net.Listen("tcp", "127.0.0.1:0")
if err != nil {
b.Fatal(err)
}
defer ln.Close()
connOut, err := net.Dial("tcp", ln.Addr().String())
if err != nil {
b.Fatal(err)
}
defer connOut.Close()
connIn, err := ln.Accept()
if err != nil {
b.Fatal(err)
}
defer connIn.Close()
brwServer := bufio.NewReadWriter(bufio.NewReader(connIn), bufio.NewWriter(connIn))
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
go s.Accept(ctx, connIn, brwServer, "test-client")
brw := bufio.NewReadWriter(bufio.NewReader(connOut), bufio.NewWriter(connOut))
client, err := NewClient(k, connOut, brw, logger.Discard)
if err != nil {
b.Fatalf("client: %v", err)
}
go func() {
for {
_, err := client.Recv()
if err != nil {
return
}
}
}()
msg := make([]byte, packetSize)
b.SetBytes(int64(len(msg)))
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i++ {
if err := client.Send(clientKey, msg); err != nil {
b.Fatal(err)
}
}
}
func BenchmarkWriteUint32(b *testing.B) {
w := bufio.NewWriter(io.Discard)
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i++ {
writeUint32(w, 0x0ba3a)
}
}
type nopRead struct{}
func (r nopRead) Read(p []byte) (int, error) {
return len(p), nil
}
var sinkU32 uint32
func BenchmarkReadUint32(b *testing.B) {
r := bufio.NewReader(nopRead{})
var err error
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i++ {
sinkU32, err = readUint32(r)
if err != nil {
b.Fatal(err)
}
}
}
func waitConnect(t testing.TB, c *Client) {
t.Helper()
if m, err := c.Recv(); err != nil {
t.Fatalf("client first Recv: %v", err)
} else if v, ok := m.(ServerInfoMessage); !ok {
t.Fatalf("client first Recv was unexpected type %T", v)
}
}
func TestParseSSOutput(t *testing.T) {
contents, err := os.ReadFile("testdata/example_ss.txt")
if err != nil {
t.Errorf("os.ReadFile(example_ss.txt) failed: %v", err)
}
seen := parseSSOutput(string(contents))
if len(seen) == 0 {
t.Errorf("parseSSOutput expected non-empty map")
}
}
type countWriter struct {
mu sync.Mutex
writes int
bytes int64
}
func (w *countWriter) Write(p []byte) (n int, err error) {
w.mu.Lock()
defer w.mu.Unlock()
w.writes++
w.bytes += int64(len(p))
return len(p), nil
}
func (w *countWriter) Stats() (writes int, bytes int64) {
w.mu.Lock()
defer w.mu.Unlock()
return w.writes, w.bytes
}
func (w *countWriter) ResetStats() {
w.mu.Lock()
defer w.mu.Unlock()
w.writes, w.bytes = 0, 0
}
func TestClientSendRateLimiting(t *testing.T) {
cw := new(countWriter)
c := &Client{
bw: bufio.NewWriter(cw),
}
c.setSendRateLimiter(ServerInfoMessage{})
pkt := make([]byte, 1000)
if err := c.send(key.NodePublic{}, pkt); err != nil {
t.Fatal(err)
}
writes1, bytes1 := cw.Stats()
if writes1 != 1 {
t.Errorf("writes = %v, want 1", writes1)
}
// Flood should all succeed.
cw.ResetStats()
for i := 0; i < 1000; i++ {
if err := c.send(key.NodePublic{}, pkt); err != nil {
t.Fatal(err)
}
}
writes1K, bytes1K := cw.Stats()
if writes1K != 1000 {
t.Logf("writes = %v; want 1000", writes1K)
}
if got, want := bytes1K, bytes1*1000; got != want {
t.Logf("bytes = %v; want %v", got, want)
}
// Set a rate limiter
cw.ResetStats()
c.setSendRateLimiter(ServerInfoMessage{
TokenBucketBytesPerSecond: 1,
TokenBucketBytesBurst: int(bytes1 * 2),
})
for i := 0; i < 1000; i++ {
if err := c.send(key.NodePublic{}, pkt); err != nil {
t.Fatal(err)
}
}
writesLimited, bytesLimited := cw.Stats()
if writesLimited == 0 || writesLimited == writes1K {
t.Errorf("limited conn's write count = %v; want non-zero, less than 1k", writesLimited)
}
if bytesLimited < bytes1*2 || bytesLimited >= bytes1K {
t.Errorf("limited conn's bytes count = %v; want >=%v, <%v", bytesLimited, bytes1K*2, bytes1K)
}
}
func TestServerRepliesToPing(t *testing.T) {
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
ts := newTestServer(t, ctx)
defer ts.close(t)
tc := newRegularClient(t, ts, "alice")
data := [8]byte{1, 2, 3, 4, 5, 6, 7, 42}
if err := tc.c.SendPing(data); err != nil {
t.Fatal(err)
}
for {
m, err := tc.c.recvTimeout(time.Second)
if err != nil {
t.Fatal(err)
}
switch m := m.(type) {
case PongMessage:
if ([8]byte(m)) != data {
t.Fatalf("got pong %2x; want %2x", [8]byte(m), data)
}
return
}
}
}